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Author SHA1 Message Date
Keith Randall
83b36ffb10 cmd/compile: implement constant rotates on arm64 
Explicit constant rotates work, but constant arguments to
bits.RotateLeft* needed the additional rule.

Fixes #48465

Change-Id: Ia7544f21d0e7587b6b6506f72421459cd769aea6
Reviewed-on: https://go-review.googlesource.com/c/go/+/350909
Trust: Keith Randall <khr@golang.org>
Trust: Josh Bleecher Snyder <josharian@gmail.com>
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
 2021-09-19 23:50:23 +00:00
Michael Munday
c69f5c0d76 cmd/compile: add support for Abs and Copysign intrinsics on riscv64 
Also, add the FABSS and FABSD pseudo instructions to the assembler.
The compiler could use FSGNJX[SD] directly but there doesn't seem
to be much advantage to doing so and the pseudo instructions are
easier to understand.

Change-Id: Ie8825b8aa8773c69cc4f07a32ef04abf4061d80d
Reviewed-on: https://go-review.googlesource.com/c/go/+/348989
Trust: Michael Munday <mike.munday@lowrisc.org>
Run-TryBot: Michael Munday <mike.munday@lowrisc.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Joel Sing <joel@sing.id.au>
 2021-09-10 10:45:59 +00:00
fanzha02
2091bd3f26 cmd/compile: simiplify arm64 bitfield optimizations 
In some rewrite rules for arm64 bitfield optimizations, the
bitfield lsb value and the bitfield width value are related
to datasize, some of them use datasize directly to check the
bitfield lsb value is valid, to get the bitfiled width value,
but some of them call isARM64BFMask() and arm64BFWidth()
functions. In order to be consistent, this patch changes them
all to use datasize.

Besides, this patch sorts the codegen test cases.

Run the "toolstash-check -all" command and find one inconsistent code
is as the following.

new:    src/math/fma.go:104      BEQ	247
master: src/math/fma.go:104      BEQ	248

The above inconsistence is due to this patch changing the range of the
field lsb value in "UBFIZ" optimization rules from "lc+(32|16|8)<64" to
"lc<64", so that the following code is generated as "UBFIZ". The logical
of changed code is still correct.

The code of src/math/fma.go:160:
  const uvinf = 0x7FF0000000000000
  func FMA(a, b uint32) float64 {
  	ps := a+b
  	return Float64frombits(uint64(ps)<<63 | uvinf)
  }

The new assembly code:
  TEXT    "".FMA(SB), LEAF|NOFRAME|ABIInternal, $0-16
  MOVWU   "".a(FP), R0
  MOVWU   "".b+4(FP), R1
  ADD     R1, R0, R0
  UBFIZ   $63, R0, $1, R0
  ORR     $9218868437227405312, R0, R0
  MOVD    R0, "".~r2+8(FP)
  RET     (R30)

The master assembly code:
  TEXT    "".FMA(SB), LEAF|NOFRAME|ABIInternal, $0-16
  MOVWU   "".a(FP), R0
  MOVWU   "".b+4(FP), R1
  ADD     R1, R0, R0
  MOVWU   R0, R0
  LSL     $63, R0, R0
  ORR     $9218868437227405312, R0, R0
  MOVD    R0, "".~r2+8(FP)
  RET     (R30)

Change-Id: I9061104adfdfd3384d0525327ae1e5c8b0df5c35
Reviewed-on: https://go-review.googlesource.com/c/go/+/265038
Trust: fannie zhang <Fannie.Zhang@arm.com>
Run-TryBot: fannie zhang <Fannie.Zhang@arm.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Cherry Mui <cherryyz@google.com>
 2021-09-10 02:44:36 +00:00
Michael Munday
8214257347 test/codegen: fix package name for test case 
The codegen tests are currently skipped (see #48247). The test
added in CL 346050 did not compile because it was in the main
package but did not contain a main function. Changing the package
to 'codegen' fixes the issue.

Updates #48247.

Change-Id: I0a0eaca8e6a7d7b335606d2c76a204ac0c12e6d5
Reviewed-on: https://go-review.googlesource.com/c/go/+/348392
Trust: Michael Munday <mike.munday@lowrisc.org>
Run-TryBot: Michael Munday <mike.munday@lowrisc.org>
Reviewed-by: Cherry Mui <cherryyz@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
 2021-09-08 14:51:40 +00:00
Michael Munday
1da64686f8 test/codegen: fix compilation of bitfield tests 
The codegen tests are currently skipped (see #48247) and the
bitfield tests do not actually compile due to a duplicate function
name (sbfiz5) added in CL 267602. Renaming the function fixes the
issue.

Updates #48247.

Change-Id: I626fd5ef13732dc358e73ace9ddcc4cbb6ae5b21
Reviewed-on: https://go-review.googlesource.com/c/go/+/348391
Trust: Michael Munday <mike.munday@lowrisc.org>
Run-TryBot: Michael Munday <mike.munday@lowrisc.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Cherry Mui <cherryyz@google.com>
 2021-09-08 14:51:31 +00:00
Michael Munday
fdc2072420 test/codegen: remove broken riscv64 test 
This test is not executed by default (see #48247) and does not
actually pass. It was added in CL 346689. The code generation
changes made in that CL only change how instructions are assembled,
they do not actually affect the output of the compiler. This test
is unfortunately therefore invalid and will never pass.

Updates #48247.

Change-Id: I0c807e4a111336e5a097fe4e3af2805f9932a87f
Reviewed-on: https://go-review.googlesource.com/c/go/+/348390
Trust: Michael Munday <mike.munday@lowrisc.org>
Run-TryBot: Michael Munday <mike.munday@lowrisc.org>
Reviewed-by: Cherry Mui <cherryyz@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
 2021-09-08 14:51:22 +00:00
wdvxdr
21de6bc463 cmd/compile: simplify less with non-negative number and constant 0 or 1 
The most common cases:
len(s) > 0
len(s) < 1

and they can be simplified to:
len(s) != 0
len(s) == 0

Fixes #48054

Change-Id: I16e5b0cffcfab62a4acc2a09977a6cd3543dd000
Reviewed-on: https://go-review.googlesource.com/c/go/+/346050
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Cherry Mui <cherryyz@google.com>
 2021-09-07 14:53:41 +00:00
fanzha02
7b69ddc171 cmd/compile: merge sign extension and shift into SBFIZ 
This patch adds some rules to rewrite "(LeftShift (SignExtend x) lc)"
expression as "SBFIZ".

Add the test cases.

Change-Id: I294c4ba09712eeb02c7a952447bb006780f1e60d
Reviewed-on: https://go-review.googlesource.com/c/go/+/267602
Trust: fannie zhang <Fannie.Zhang@arm.com>
Trust: Cherry Mui <cherryyz@google.com>
Run-TryBot: fannie zhang <Fannie.Zhang@arm.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
 2021-09-06 03:31:53 +00:00
fanzha02
43b05173a2 cmd/compile: merge zero/sign extensions with UBFX/SBFX on arm64 
The UBFX and SBFX already zero/sign extend the result. Further
zero/sign extensions are thus unnecessary as long as they leave
the top bits unaltered. This patch absorbs zero/sign extensions
into UBFX/SBFX.

Add the related test cases.

Change-Id: I7c4516c8b52d677f77bf3aaedab87c4a28056ec0
Reviewed-on: https://go-review.googlesource.com/c/go/+/265039
Trust: fannie zhang <Fannie.Zhang@arm.com>
Trust: Keith Randall <khr@golang.org>
Run-TryBot: fannie zhang <Fannie.Zhang@arm.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Cherry Mui <cherryyz@google.com>
 2021-09-06 03:31:43 +00:00
Ben Shi
37d4532867 cmd/internal/obj/riscv: simplify addition with constant 
This CL simplifies riscv addition (add r, imm) to
(ADDI (ADDI r, imm/2), imm-imm/2) if imm is in specific ranges.
(-4096 <= imm <= -2049 or 2048 <= imm <= 4094)

There is little impact to the go1 benchmark, while the total
size of pkg/linux_riscv64 decreased by about 11KB.

Change-Id: I236eb8af3b83bb35ce9c0b318fc1d235e8ab9a4e
GitHub-Last-Rev: a2f56a0763
GitHub-Pull-Request: golang/go#48110
Reviewed-on: https://go-review.googlesource.com/c/go/+/346689
Run-TryBot: Ben Shi <powerman1st@163.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Joel Sing <joel@sing.id.au>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Reviewed-by: Keith Randall <khr@golang.org>
Trust: Michael Munday <mike.munday@lowrisc.org>
 2021-09-02 14:35:10 +00:00
Michael Munday
ea51e223c2 cmd/{asm,compile}: add fused multiply-add support on riscv64 
Add support to the assembler for F[N]M{ADD,SUB}[SD] instructions.
Argument order is:

  OP RS1, RS2, RS3, RD

Also, add support for the FMA intrinsic to the compiler. Automatic
FMA matching is left to a future CL.

Change-Id: I47166c7393b2ab6bfc2e42aa8c1a8997c3a071b3
Reviewed-on: https://go-review.googlesource.com/c/go/+/293030
Trust: Michael Munday <mike.munday@lowrisc.org>
Run-TryBot: Michael Munday <mike.munday@lowrisc.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Joel Sing <joel@sing.id.au>
 2021-09-01 21:17:04 +00:00
Jake Ciolek
6cf1d5d0fa cmd/compile: generic SSA rules for simplifying 2 and 3 operand integer arithmetic expressions 
This applies the following generic integer addition/subtraction transformations:

x - (x + y) = -y
(x - y) - x = -y
y + (x - y) = x
y + (z + (x - y) = x + z

There's over 40 unique functions matching in Go. Hits 2 funcs in the runtime itself:

runtime.stackfree()
runtime.runqdrain()

Go binary size reduced by 0.05% on Linux x86_64.

StackCopy bench (perflocked Cascade Lake x86):

name                old time/op  new time/op  delta
StackCopyPtr-8      87.3ms ± 1%  86.9ms ± 0%  -0.45%  (p=0.000 n=20+20)
StackCopy-8         77.6ms ± 1%  77.0ms ± 0%  -0.76%  (p=0.000 n=20+20)
StackCopyNoCache-8  2.28ms ± 2%  2.26ms ± 2%  -0.93%  (p=0.008 n=19+20)

test/bench/go1 benchmarks (perflocked Cascade Lake x86):

name                     old time/op    new time/op    delta
BinaryTree17-8              1.88s ± 1%     1.88s ± 0%    ~     (p=0.373 n=15+12)
Fannkuch11-8                2.31s ± 0%     2.35s ± 0%  +1.52%  (p=0.000 n=15+14)
FmtFprintfEmpty-8          26.6ns ± 0%    26.6ns ± 0%    ~     (p=0.081 n=14+13)
FmtFprintfString-8         48.6ns ± 0%    50.0ns ± 0%  +2.86%  (p=0.000 n=15+14)
FmtFprintfInt-8            56.9ns ± 0%    54.8ns ± 0%  -3.70%  (p=0.000 n=15+15)
FmtFprintfIntInt-8         90.4ns ± 0%    88.8ns ± 0%  -1.78%  (p=0.000 n=15+15)
FmtFprintfPrefixedInt-8     104ns ± 0%     104ns ± 0%    ~     (p=0.905 n=14+13)
FmtFprintfFloat-8           148ns ± 0%     144ns ± 0%  -2.19%  (p=0.000 n=14+15)
FmtManyArgs-8               389ns ± 0%     390ns ± 0%  +0.35%  (p=0.000 n=12+15)
GobDecode-8                3.90ms ± 1%    3.88ms ± 0%  -0.49%  (p=0.000 n=15+14)
GobEncode-8                2.73ms ± 0%    2.73ms ± 0%    ~     (p=0.425 n=15+14)
Gzip-8                      169ms ± 0%     168ms ± 0%  -0.52%  (p=0.000 n=13+13)
Gunzip-8                   24.7ms ± 0%    24.8ms ± 0%  +0.61%  (p=0.000 n=15+15)
HTTPClientServer-8         60.5µs ± 6%    60.4µs ± 7%    ~     (p=0.595 n=15+15)
JSONEncode-8               6.97ms ± 1%    6.93ms ± 0%  -0.69%  (p=0.000 n=14+14)
JSONDecode-8               31.2ms ± 1%    30.8ms ± 1%  -1.27%  (p=0.000 n=14+14)
Mandelbrot200-8            3.87ms ± 0%    3.87ms ± 0%    ~     (p=0.652 n=15+14)
GoParse-8                  2.65ms ± 2%    2.64ms ± 1%    ~     (p=0.202 n=15+15)
RegexpMatchEasy0_32-8      45.1ns ± 0%    45.9ns ± 0%  +1.68%  (p=0.000 n=14+15)
RegexpMatchEasy0_1K-8       140ns ± 0%     139ns ± 0%  -0.44%  (p=0.000 n=15+14)
RegexpMatchEasy1_32-8      40.9ns ± 3%    40.5ns ± 0%  -0.88%  (p=0.000 n=15+13)
RegexpMatchEasy1_1K-8       215ns ± 1%     220ns ± 1%  +2.27%  (p=0.000 n=15+15)
RegexpMatchMedium_32-8      783ns ± 7%     738ns ± 0%    ~     (p=0.361 n=15+15)
RegexpMatchMedium_1K-8     24.1µs ± 6%    23.4µs ± 6%  -2.94%  (p=0.004 n=15+15)
RegexpMatchHard_32-8       1.10µs ± 1%    1.09µs ± 1%  -0.40%  (p=0.006 n=15+14)
RegexpMatchHard_1K-8       33.0µs ± 0%    33.0µs ± 0%    ~     (p=0.535 n=12+14)
Revcomp-8                   354ms ± 0%     353ms ± 0%  -0.23%  (p=0.002 n=15+13)
Template-8                 42.0ms ± 1%    41.8ms ± 2%  -0.37%  (p=0.023 n=14+15)
TimeParse-8                 181ns ± 0%     180ns ± 1%  -0.18%  (p=0.014 n=12+13)
TimeFormat-8                240ns ± 0%     242ns ± 1%  +0.69%  (p=0.000 n=12+15)
[Geo mean]                 35.2µs         35.1µs       -0.43%

name                     old speed      new speed      delta
GobDecode-8               197MB/s ± 1%   198MB/s ± 0%  +0.49%  (p=0.000 n=15+14)
GobEncode-8               281MB/s ± 0%   281MB/s ± 0%    ~     (p=0.419 n=15+14)
Gzip-8                    115MB/s ± 0%   115MB/s ± 0%  +0.52%  (p=0.000 n=13+13)
Gunzip-8                  786MB/s ± 0%   781MB/s ± 0%  -0.60%  (p=0.000 n=15+15)
JSONEncode-8              278MB/s ± 1%   280MB/s ± 0%  +0.69%  (p=0.000 n=14+14)
JSONDecode-8             62.3MB/s ± 1%  63.1MB/s ± 1%  +1.29%  (p=0.000 n=14+14)
GoParse-8                21.9MB/s ± 2%  22.0MB/s ± 1%    ~     (p=0.205 n=15+15)
RegexpMatchEasy0_32-8     709MB/s ± 0%   697MB/s ± 0%  -1.65%  (p=0.000 n=14+15)
RegexpMatchEasy0_1K-8    7.34GB/s ± 0%  7.37GB/s ± 0%  +0.43%  (p=0.000 n=15+15)
RegexpMatchEasy1_32-8     783MB/s ± 2%   790MB/s ± 0%  +0.88%  (p=0.000 n=15+13)
RegexpMatchEasy1_1K-8    4.77GB/s ± 1%  4.66GB/s ± 1%  -2.23%  (p=0.000 n=15+15)
RegexpMatchMedium_32-8   41.0MB/s ± 7%  43.3MB/s ± 0%    ~     (p=0.360 n=15+15)
RegexpMatchMedium_1K-8   42.5MB/s ± 6%  43.8MB/s ± 6%  +3.07%  (p=0.004 n=15+15)
RegexpMatchHard_32-8     29.2MB/s ± 1%  29.3MB/s ± 1%  +0.41%  (p=0.006 n=15+14)
RegexpMatchHard_1K-8     31.1MB/s ± 0%  31.1MB/s ± 0%    ~     (p=0.495 n=12+14)
Revcomp-8                 718MB/s ± 0%   720MB/s ± 0%  +0.23%  (p=0.002 n=15+13)
Template-8               46.3MB/s ± 1%  46.4MB/s ± 2%  +0.38%  (p=0.021 n=14+15)
[Geo mean]                205MB/s        206MB/s       +0.57%

Change-Id: Ibd1afdf8b6c0b08087dcc3acd8f943637eb95ac0
Reviewed-on: https://go-review.googlesource.com/c/go/+/344930
Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Trust: Josh Bleecher Snyder <josharian@gmail.com>
 2021-08-25 19:45:20 +00:00
Meng Zhuo
efd206eb40 cmd/compile: intrinsify Mul64 on riscv64 
According to RISCV instruction set manual v2.2 Sec 6.1
MULHU followed by MUL will be fused into one multiply by microarchitecture

Benchstat on Hifive unmatched:
name          old time/op    new time/op    delta
Hash8Bytes       245ns ± 3%     186ns ± 4%  -23.99%  (p=0.000 n=10+10)
Hash320Bytes    1.94µs ± 1%    1.31µs ± 1%  -32.38%  (p=0.000 n=9+10)
Hash1K          5.84µs ± 0%    3.84µs ± 0%  -34.20%  (p=0.000 n=10+9)
Hash8K          45.3µs ± 0%    29.4µs ± 0%  -35.04%  (p=0.000 n=10+10)

name          old speed      new speed      delta
Hash8Bytes    32.7MB/s ± 3%  43.0MB/s ± 4%  +31.61%  (p=0.000 n=10+10)
Hash320Bytes   165MB/s ± 1%   244MB/s ± 1%  +47.88%  (p=0.000 n=9+10)
Hash1K         175MB/s ± 0%   266MB/s ± 0%  +51.98%  (p=0.000 n=10+9)
Hash8K         181MB/s ± 0%   279MB/s ± 0%  +53.94%  (p=0.000 n=10+10)

Change-Id: I3561495d02a4a0ad8578e9b9819bf0a4eaca5d12
Reviewed-on: https://go-review.googlesource.com/c/go/+/329970
Reviewed-by: Joel Sing <joel@sing.id.au>
Run-TryBot: Joel Sing <joel@sing.id.au>
TryBot-Result: Go Bot <gobot@golang.org>
Trust: Meng Zhuo <mzh@golangcn.org>
 2021-08-16 13:50:11 +00:00
Cherry Mui
6b1e4430bb [dev.typeparams] cmd/compile: implement clobberdead mode on ARM64 
For debugging.

Change-Id: I5875ccd2413b8ffd2ec97a0ace66b5cae7893b24
Reviewed-on: https://go-review.googlesource.com/c/go/+/324765
Trust: Cherry Mui <cherryyz@google.com>
Run-TryBot: Cherry Mui <cherryyz@google.com>
Reviewed-by: Than McIntosh <thanm@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
 2021-06-03 20:00:30 +00:00
Cherry Mui
165d39a1d4 [dev.typeparams] test: adjust codegen test for register ABI on ARM64 
In codegen/arithmetic.go, previously there are MOVD's that match
for loads of arguments. With register ABI there are no more such
loads. Remove the MOVD matches.

Change-Id: I920ee2629c8c04d454f13a0c08e283d3528d9a64
Reviewed-on: https://go-review.googlesource.com/c/go/+/324251
Trust: Cherry Mui <cherryyz@google.com>
Run-TryBot: Cherry Mui <cherryyz@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
 2021-06-03 14:28:14 +00:00
Ruslan Andreev
3b321a9d12 cmd/compile: add arch-specific inlining for runtime.memmove 
This CL add runtime.memmove inlining for AMD64 and ARM64.
According to ssa dump from testcases generic rules can't inline
memmomve properly due to one of the arguments is Phi operation. But this
Phi op will be optimized out by later optimization stages. As a result
memmove can be inlined during arch-specific rules.
The commit add new optimization rules to arch-specific rules that can
inline runtime.memmove if it possible during lowering stage.
Optimization fires 5 times in Go source-code using regabi.

Fixes #41662

Change-Id: Iaffaf4c482d068b5f0683d141863892202cc8824
Reviewed-on: https://go-review.googlesource.com/c/go/+/289151
Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Trust: David Chase <drchase@google.com>
 2021-05-12 16:23:30 +00:00
Keith Randall
b211fe0058 cmd/compile: remove bit operations that modify memory directly 
These operations (BT{S,R,C}{Q,L}modify) are quite a bit slower than
other ways of doing the same thing.

Without the BTxmodify operations, there are two fallback ways the compiler
performs these operations: AND/OR/XOR operations directly on memory, or
load-BTx-write sequences. The compiler kinda chooses one arbitrarily
depending on rewrite rule application order. Currently, it uses
load-BTx-write for the Const benchmarks and AND/OR/XOR directly to memory
for the non-Const benchmarks. TBD, someone might investigate which of
the two fallback strategies is really better. For now, they are both
better than BTx ops.

name              old time/op  new time/op  delta
BitSet-8          1.09µs ± 2%  0.64µs ± 5%  -41.60%  (p=0.000 n=9+10)
BitClear-8        1.15µs ± 3%  0.68µs ± 6%  -41.00%  (p=0.000 n=10+10)
BitToggle-8       1.18µs ± 4%  0.73µs ± 2%  -38.36%  (p=0.000 n=10+8)
BitSetConst-8     37.0ns ± 7%  25.8ns ± 2%  -30.24%  (p=0.000 n=10+10)
BitClearConst-8   30.7ns ± 2%  25.0ns ±12%  -18.46%  (p=0.000 n=10+10)
BitToggleConst-8  36.9ns ± 1%  23.8ns ± 3%  -35.46%  (p=0.000 n=9+10)

Fixes #45790
Update #45242

Change-Id: Ie33a72dc139f261af82db15d446cd0855afb4e59
Reviewed-on: https://go-review.googlesource.com/c/go/+/318149
Trust: Keith Randall <khr@golang.org>
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Ben Shi <powerman1st@163.com>
 2021-05-08 03:27:59 +00:00
Cherry Zhang
6b8e3e2d06 cmd/compile: reduce redundant register moves for regabi calls 
Currently, if we have AX=a and BX=b, and we want to make a call
F(1, a, b), to move arguments into the desired registers it emits

	MOVQ AX, CX
	MOVL $1, AX // AX=1
	MOVQ BX, DX
	MOVQ CX, BX // BX=a
	MOVQ DX, CX // CX=b

This has a few redundant moves.

This is because we process inputs in order. First, allocate 1 to
AX, which kicks out a (in AX) to CX (a free register at the
moment). Then, allocate a to BX, which kicks out b (in BX) to DX.
Finally, put b to CX.

Notice that if we start with allocating CX=b, then BX=a, AX=1,
we will not have redundant moves. This CL reduces redundant moves
by allocating them in different order: First, for inpouts that are
already in place, keep them there. Then allocate free registers.
Then everything else.

                             before       after
cmd/compile binary size     23703888    23609680
            text size        8565899     8533291

(with regabiargs enabled.)

Change-Id: I69e1bdf745f2c90bb791f6d7c45b37384af1e874
Reviewed-on: https://go-review.googlesource.com/c/go/+/311371
Trust: Cherry Zhang <cherryyz@google.com>
Reviewed-by: David Chase <drchase@google.com>
Reviewed-by: Than McIntosh <thanm@google.com>
 2021-04-19 16:21:39 +00:00
David Chase
4df3d0e4df cmd/compile: rescue stmt boundaries from OpArgXXXReg and OpSelectN. 
Fixes this failure:
go test cmd/compile/internal/ssa -run TestStmtLines -v
=== RUN   TestStmtLines
    stmtlines_test.go:115: Saw too many (amd64, > 1%) lines without
    statement marks, total=88263, nostmt=1930
    ('-run TestStmtLines -v' lists failing lines)

The failure has two causes.

One is that the first-line adjuster in code generation was relocating
"first lines" to instructions that would either not have any code generated,
or would have the statment marker removed by a different believed-good heuristic.

The other was that statement boundaries were getting attached to register
values (that with the old ABI were loads from the stack, hence real instructions).
The register values disappear at code generation.

The fixes are to (1) note that certain instructions are not good choices for
"first value" and skip them, and (2) in an expandCalls post-pass, look for
register valued instructions and under appropriate conditions move their
statement marker to a compatible use.

Also updates TestStmtLines to always log the score, for easier comparison of
minor compiler changes.

Updates #40724.

Change-Id: I485573ce900e292d7c44574adb7629cdb4695c3f
Reviewed-on: https://go-review.googlesource.com/c/go/+/309649
Trust: David Chase <drchase@google.com>
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
 2021-04-14 18:46:08 +00:00
Cherry Zhang
444d28295b test: make codegen/memops.go work with both ABIs 
Following CL 309335, this fixes memops.go.

Change-Id: Ia2458b5267deee9f906f76c50e70a021ea2fcb5b
Reviewed-on: https://go-review.googlesource.com/c/go/+/309552
Trust: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
Reviewed-by: Than McIntosh <thanm@google.com>
 2021-04-13 14:07:17 +00:00
Cherry Zhang
263e13d1f7 test: make codegen tests work with both ABIs 
Some codegen tests were written with the assumption that
arguments and results are in memory, and with a specific stack
layout. With the register ABI, the assumption is no longer true.
Adjust the tests to work with both cases.

- For tests expecting in memory arguments/results, change to use
  global variables or memory-assigned argument/results.

- Allow more registers. E.g. some tests expecting register names
  contain only letters (e.g. AX), but  it can also contain numbers
  (e.g. R10).

- Some instruction selection changes when operate on register vs.
  memory, e.g. ADDQ vs. LEAQ, MOVB vs. MOVL. Accept both.

TODO: mathbits.go and memops.go still need fix.
Change-Id: Ic5932b4b5dd3f5d30ed078d296476b641420c4c5
Reviewed-on: https://go-review.googlesource.com/c/go/+/309335
Trust: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
 2021-04-12 21:59:59 +00:00
Pat Gavlin
359f44910f cmd/compile: fix long RMW bit operations on AMD64 
Under certain circumstances, the existing rules for bit operations can
produce code that writes beyond its intended bounds. For example,
consider the following code:

    func repro(b []byte, addr, bit int32) {
	    _ = b[3]
	    v := uint32(b[0]) | uint32(b[1])<<8 | uint32(b[2])<<16 | uint32(b[3])<<24 | 1<<(bit&31)
	    b[0] = byte(v)
	    b[1] = byte(v >> 8)
	    b[2] = byte(v >> 16)
	    b[3] = byte(v >> 24)
    }

Roughly speaking:

1. The expression `1 << (bit & 31)` is rewritten into `(SHLL 1 bit)`
2. The expression `uint32(b[0]) | uint32(b[1])<<8 | uint32(b[2])<<16 |
   uint32(b[3])<<24` is rewritten into `(MOVLload &b[0])`
3. The statements `b[0] = byte(v) ... b[3] = byte(v >> 24)` are
   rewritten into `(MOVLstore &b[0], v)`
4. `(ORL (SHLL 1, bit) (MOVLload &b[0]))` is rewritten into
   `(BTSL (MOVLload &b[0]) bit)`. This is a valid transformation because
   the destination is a register: in this case, the bit offset is masked
   by the number of bits in the destination register. This is identical
   to the masking performed by `SHL`.
5. `(MOVLstore &b[0] (BTSL (MOVLload &b[0]) bit))` is rewritten into
   `(BTSLmodify &b[0] bit)`. This is an invalid transformation because
   the destination is memory: in this case, the bit offset is not
   masked, and the chosen instruction may write outside its intended
   32-bit location.

These changes fix the invalid rewrite performed in step (5) by
explicitly maksing the bit offset operand to `BT(S|R|C)(L|Q)modify`. In
the example above, the adjusted rules produce
`(BTSLmodify &b[0] (ANDLconst [31] bit))` in step (5).

These changes also add several new rules to rewrite bit sets, toggles,
and clears that are rooted at `(OR|XOR|AND)(L|Q)modify` operators into
appropriate `BT(S|R|C)(L|Q)modify` operators. These rules catch cases
where `MOV(L|Q)store ((OR|XOR|AND)(L|Q) ...)` is rewritten to
`(OR|XOR|AND)(L|Q)modify` before the `(OR|XOR|AND)(L|Q) ...` can be
rewritten to `BT(S|R|C)(L|Q) ...`.

Overall, compilecmp reports small improvements in code size on
darwin/amd64 when the changes to the compiler itself are exlcuded:

file                               before   after    Δ       %
runtime.s                          536464   536412   -52     -0.010%
bytes.s                            32629    32593    -36     -0.110%
strings.s                          44565    44529    -36     -0.081%
os/signal.s                        7967     7959     -8      -0.100%
cmd/vendor/golang.org/x/sys/unix.s 81686    81678    -8      -0.010%
math/big.s                         188235   188253   +18     +0.010%
cmd/link/internal/loader.s         89295    89056    -239    -0.268%
cmd/link/internal/ld.s             633551   633232   -319    -0.050%
cmd/link/internal/arm.s            18934    18928    -6      -0.032%
cmd/link/internal/arm64.s          31814    31801    -13     -0.041%
cmd/link/internal/riscv64.s        7347     7345     -2      -0.027%
cmd/compile/internal/ssa.s         4029173  4033066  +3893   +0.097%
total                              21298280 21301472 +3192   +0.015%

Change-Id: I2e560548b515865129e1724e150e30540e9d29ce
GitHub-Last-Rev: 9a42bd29a5
GitHub-Pull-Request: golang/go#45242
Reviewed-on: https://go-review.googlesource.com/c/go/+/304869
Reviewed-by: Keith Randall <khr@golang.org>
Trust: Josh Bleecher Snyder <josharian@gmail.com>
 2021-03-26 19:40:37 +00:00
fanzha02
3a0061822e cmd/compile: add arm64 rules to optimize go codes to constant 0 
Optimize the following codes to constant 0.

  function shift (x uint32) uint64 {
    return uint64(x) >> 32
  }

Change-Id: Ida6b39d713cc119ad5a2f01fd54bfd252cf2c975
Reviewed-on: https://go-review.googlesource.com/c/go/+/303830
Trust: fannie zhang <Fannie.Zhang@arm.com>
Run-TryBot: fannie zhang <Fannie.Zhang@arm.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
 2021-03-26 01:57:35 +00:00
fanzha02
b182ba7fab cmd/compile: optimize codes with arm64 REV16 instruction 
Optimize some patterns into rev16/rev16w instruction.

Pattern1:
    (c & 0xff00ff00)>>8 | (c & 0x00ff00ff)<<8
To:
    rev16w c

Pattern2:
    (c & 0xff00ff00ff00ff00)>>8 | (c & 0x00ff00ff00ff00ff)<<8
To:
    rev16 c

This patch is a copy of CL 239637, contributed by Alice Xu(dianhong.xu@arm.com).

Change-Id: I96936c1db87618bc1903c04221c7e9b2779455b3
Reviewed-on: https://go-review.googlesource.com/c/go/+/268377
Trust: fannie zhang <Fannie.Zhang@arm.com>
Run-TryBot: fannie zhang <Fannie.Zhang@arm.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
 2021-03-23 01:36:23 +00:00
Cherry Zhang
6ae3b70ef2 cmd/compile: add clobberdeadreg mode 
When -clobberdeadreg flag is set, the compiler inserts code that
clobbers integer registers at call sites. This may be helpful for
debugging register ABI.

Only implemented on AMD64 for now.

Change-Id: Ia203d3f891c30fd95d0103489056fe01d63a2899
Reviewed-on: https://go-review.googlesource.com/c/go/+/302809
Trust: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
 2021-03-19 23:21:21 +00:00
fanzha02
f5e6d3e879 cmd/compile: add rewrite rules for conditional instructions on arm64 
This CL adds rewrite rules for CSETM, CSINC, CSINV, and CSNEG. By adding
these rules, we can save one instruction.

For example,

  func test(cond bool, a int) int {
    if cond {
      a++
    }
    return a
  }

Before:

  MOVD "".a+8(RSP), R0
  ADD $1, R0, R1
  MOVBU "".cond(RSP), R2
  CMPW $0, R2
  CSEL NE, R1, R0, R0

After:

  MOVBU "".cond(RSP), R0
  CMPW $0, R0
  MOVD "".a+8(RSP), R0
  CSINC EQ, R0, R0, R0

This patch is a copy of CL 285694. Co-authored-by: JunchenLi
<junchen.li@arm.com>

Change-Id: Ic1a79e8b8ece409b533becfcb7950f11e7b76f24
Reviewed-on: https://go-review.googlesource.com/c/go/+/302231
Trust: fannie zhang <Fannie.Zhang@arm.com>
Run-TryBot: fannie zhang <Fannie.Zhang@arm.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
 2021-03-18 01:46:58 +00:00
Cherry Zhang
8628bf9a97 cmd/compile: resurrect clobberdead mode 
This CL resurrects the clobberdead debugging mode (CL 23924).
When -clobberdead flag is set (TODO: make it GOEXPERIMENT?), the
compiler inserts code that clobbers all dead stack slots that
contains pointers.

Mark windows syscall functions cgo_unsafe_args, as the code
actually does that, by taking the address of one argument and
passing it to cgocall.

Change-Id: Ie09a015f4bd14ae6053cc707866e30ae509b9d6f
Reviewed-on: https://go-review.googlesource.com/c/go/+/301791
Trust: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
Reviewed-by: Than McIntosh <thanm@google.com>
 2021-03-17 17:50:50 +00:00
Meng Zhuo
afe517590c cmd/compile: loads from readonly globals into const for mips64x 
Ref: CL 141118
Update #26498

Change-Id: If4ea55c080b9aa10183eefe81fefbd4072deaf3a
Reviewed-on: https://go-review.googlesource.com/c/go/+/280646
Trust: Meng Zhuo <mzh@golangcn.org>
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
 2021-03-16 09:07:17 +00:00
erifan01
600259b099 cmd/compile: use depth first topological sort algorithm for layout 
The current layout algorithm tries to put consecutive blocks together,
so the priority of the successor block is higher than the priority of
the zero indegree block. This algorithm is beneficial for subsequent
register allocation, but will result in more branch instructions.
The depth-first topological sorting algorithm is a well-known layout
algorithm, which has applications in many languages, and it helps to
reduce branch instructions. This CL applies it to the layout pass.
The test results show that it helps to reduce the code size.

This CL also includes the following changes:
1, Removed the primary predecessor mechanism. The new layout algorithm is
  not very friendly to register allocator in some cases, in order to adapt
  to the new layout algorithm, a new primary predecessor selection strategy
  is introduced.
2, Since the new layout implementation may place non-loop blocks between
  loop blocks, some adaptive modifications have also been made to looprotate
  pass.
3, The layout also affects the results of codegen, so this CL also adjusted
  several codegen tests accordingly.

It is inevitable that this CL will cause the code size or performance of a
few functions to decrease, but the number of cases it improves is much larger
than the number of cases it drops.

Statistical data from compilecmp on linux/amd64 is as follow:
name                      old time/op       new time/op       delta
Template                        382ms ± 4%        382ms ± 4%    ~     (p=0.497 n=49+50)
Unicode                         170ms ± 9%        169ms ± 8%    ~     (p=0.344 n=48+50)
GoTypes                         2.01s ± 4%        2.01s ± 4%    ~     (p=0.628 n=50+48)
Compiler                        190ms ±10%        189ms ± 9%    ~     (p=0.734 n=50+50)
SSA                             11.8s ± 2%        11.8s ± 3%    ~     (p=0.877 n=50+50)
Flate                           241ms ± 9%        241ms ± 8%    ~     (p=0.897 n=50+49)
GoParser                        366ms ± 3%        361ms ± 4%  -1.21%  (p=0.004 n=47+50)
Reflect                         835ms ± 3%        838ms ± 3%    ~     (p=0.275 n=50+49)
Tar                             336ms ± 4%        335ms ± 3%    ~     (p=0.454 n=48+48)
XML                             433ms ± 4%        431ms ± 3%    ~     (p=0.071 n=49+48)
LinkCompiler                    706ms ± 4%        705ms ± 4%    ~     (p=0.608 n=50+49)
ExternalLinkCompiler            1.85s ± 3%        1.83s ± 2%  -1.47%  (p=0.000 n=49+48)
LinkWithoutDebugCompiler        437ms ± 5%        437ms ± 6%    ~     (p=0.953 n=49+50)
[Geo mean]                      615ms             613ms       -0.37%

name                      old alloc/op      new alloc/op      delta
Template                       38.7MB ± 1%       38.7MB ± 1%    ~     (p=0.834 n=50+50)
Unicode                        28.1MB ± 0%       28.1MB ± 0%  -0.22%  (p=0.000 n=49+50)
GoTypes                         168MB ± 1%        168MB ± 1%    ~     (p=0.054 n=47+47)
Compiler                       23.0MB ± 1%       23.0MB ± 1%    ~     (p=0.432 n=50+50)
SSA                            1.54GB ± 0%       1.54GB ± 0%  +0.21%  (p=0.000 n=50+50)
Flate                          23.6MB ± 1%       23.6MB ± 1%    ~     (p=0.153 n=43+46)
GoParser                       35.1MB ± 1%       35.1MB ± 2%    ~     (p=0.202 n=50+50)
Reflect                        84.7MB ± 1%       84.7MB ± 1%    ~     (p=0.333 n=48+49)
Tar                            34.5MB ± 1%       34.5MB ± 1%    ~     (p=0.406 n=46+49)
XML                            44.3MB ± 2%       44.2MB ± 3%    ~     (p=0.981 n=50+50)
LinkCompiler                    131MB ± 0%        128MB ± 0%  -2.74%  (p=0.000 n=50+50)
ExternalLinkCompiler            120MB ± 0%        120MB ± 0%  +0.01%  (p=0.007 n=50+50)
LinkWithoutDebugCompiler       77.3MB ± 0%       77.3MB ± 0%  -0.02%  (p=0.000 n=50+50)
[Geo mean]                     69.3MB            69.1MB       -0.22%

file      before    after     Δ        %
addr2line 4104220   4043684   -60536   -1.475%
api       5342502   5249678   -92824   -1.737%
asm       4973785   4858257   -115528  -2.323%
buildid   2667844   2625660   -42184   -1.581%
cgo       4686849   4616313   -70536   -1.505%
compile   23667431  23268406  -399025  -1.686%
cover     4959676   4874108   -85568   -1.725%
dist      3515934   3450422   -65512   -1.863%
doc       3995581   3925469   -70112   -1.755%
fix       3379202   3318522   -60680   -1.796%
link      6743249   6629913   -113336  -1.681%
nm        4047529   3991777   -55752   -1.377%
objdump   4456151   4388151   -68000   -1.526%
pack      2435040   2398072   -36968   -1.518%
pprof     13804080  13565808  -238272  -1.726%
test2json 2690043   2645987   -44056   -1.638%
trace     10418492  10232716  -185776  -1.783%
vet       7258259   7121259   -137000  -1.888%
total     113145867 111204202 -1941665 -1.716%

The situation on linux/arm64 is as follow:
name                      old time/op       new time/op       delta
Template                        280ms ± 1%        282ms ± 1%  +0.75%  (p=0.000 n=46+48)
Unicode                         124ms ± 2%        124ms ± 2%  +0.37%  (p=0.045 n=50+50)
GoTypes                         1.69s ± 1%        1.70s ± 1%  +0.56%  (p=0.000 n=49+50)
Compiler                        122ms ± 1%        123ms ± 1%  +0.93%  (p=0.000 n=50+50)
SSA                             12.6s ± 1%        12.7s ± 0%  +0.72%  (p=0.000 n=50+50)
Flate                           170ms ± 1%        172ms ± 1%  +0.97%  (p=0.000 n=49+49)
GoParser                        262ms ± 1%        263ms ± 1%  +0.39%  (p=0.000 n=49+48)
Reflect                         639ms ± 1%        650ms ± 1%  +1.63%  (p=0.000 n=49+49)
Tar                             243ms ± 1%        245ms ± 1%  +0.82%  (p=0.000 n=50+50)
XML                             324ms ± 1%        327ms ± 1%  +0.72%  (p=0.000 n=50+49)
LinkCompiler                    597ms ± 1%        596ms ± 1%  -0.27%  (p=0.001 n=48+47)
ExternalLinkCompiler            1.90s ± 1%        1.88s ± 1%  -1.00%  (p=0.000 n=50+50)
LinkWithoutDebugCompiler        364ms ± 1%        363ms ± 1%    ~     (p=0.220 n=49+50)
[Geo mean]                      485ms             488ms       +0.49%

name                      old alloc/op      new alloc/op      delta
Template                       38.7MB ± 0%       38.8MB ± 1%    ~     (p=0.093 n=43+49)
Unicode                        28.4MB ± 0%       28.4MB ± 0%  +0.03%  (p=0.000 n=49+45)
GoTypes                         169MB ± 1%        169MB ± 1%  +0.23%  (p=0.010 n=50+50)
Compiler                       23.2MB ± 1%       23.2MB ± 1%  +0.11%  (p=0.000 n=40+44)
SSA                            1.54GB ± 0%       1.55GB ± 0%  +0.45%  (p=0.000 n=47+49)
Flate                          23.8MB ± 2%       23.8MB ± 1%    ~     (p=0.543 n=50+50)
GoParser                       35.3MB ± 1%       35.4MB ± 1%    ~     (p=0.792 n=50+50)
Reflect                        85.2MB ± 1%       85.2MB ± 0%    ~     (p=0.055 n=50+47)
Tar                            34.5MB ± 1%       34.5MB ± 1%  +0.06%  (p=0.015 n=50+50)
XML                            43.8MB ± 2%       43.9MB ± 2%  +0.19%  (p=0.000 n=48+48)
LinkCompiler                    137MB ± 0%        136MB ± 0%  -0.92%  (p=0.000 n=50+50)
ExternalLinkCompiler            127MB ± 0%        127MB ± 0%    ~     (p=0.516 n=50+50)
LinkWithoutDebugCompiler       84.0MB ± 0%       84.0MB ± 0%    ~     (p=0.057 n=50+50)
[Geo mean]                     70.4MB            70.4MB       +0.01%

file      before    after     Δ        %
addr2line 4021557   4002933   -18624   -0.463%
api       5127847   5028503   -99344   -1.937%
asm       5034716   4936836   -97880   -1.944%
buildid   2608118   2594094   -14024   -0.538%
cgo       4488592   4398320   -90272   -2.011%
compile   22501129  22213592  -287537  -1.278%
cover     4742301   4713573   -28728   -0.606%
dist      3388071   3365311   -22760   -0.672%
doc       3802250   3776082   -26168   -0.688%
fix       3306147   3216939   -89208   -2.698%
link      6404483   6363699   -40784   -0.637%
nm        3941026   3921930   -19096   -0.485%
objdump   4383330   4295122   -88208   -2.012%
pack      2404547   2389515   -15032   -0.625%
pprof     12996234  12856818  -139416  -1.073%
test2json 2668500   2586788   -81712   -3.062%
trace     9816276   9609580   -206696  -2.106%
vet       6900682   6787338   -113344  -1.643%
total     108535806 107056973 -1478833 -1.363%

Change-Id: Iaec1cdcaacca8025e9babb0fb8a532fddb70c87d
Reviewed-on: https://go-review.googlesource.com/c/go/+/255239
Reviewed-by: eric fang <eric.fang@arm.com>
Reviewed-by: Keith Randall <khr@golang.org>
Trust: eric fang <eric.fang@arm.com>
 2021-03-16 02:44:54 +00:00
Josh Bleecher Snyder
43d5f213e2 cmd/compile: optimize multi-register shifts on amd64 
amd64 can shift in bits from another register instead of filling with 0/1.
This pattern is helpful when implementing 128 bit shifts or arbitrary length shifts.
In the standard library, it shows up in pure Go math/big.

Benchmarks results on amd64 with -tags=math_big_pure_go.

name                          old time/op  new time/op  delta
NonZeroShifts/1/shrVU-8       4.45ns ± 3%  4.39ns ± 1%   -1.28%  (p=0.000 n=30+27)
NonZeroShifts/1/shlVU-8       4.13ns ± 4%  4.10ns ± 2%     ~     (p=0.254 n=29+28)
NonZeroShifts/2/shrVU-8       5.55ns ± 1%  5.63ns ± 2%   +1.42%  (p=0.000 n=28+29)
NonZeroShifts/2/shlVU-8       5.70ns ± 2%  5.14ns ± 1%   -9.82%  (p=0.000 n=29+28)
NonZeroShifts/3/shrVU-8       6.79ns ± 2%  6.35ns ± 2%   -6.46%  (p=0.000 n=28+29)
NonZeroShifts/3/shlVU-8       6.69ns ± 1%  6.25ns ± 1%   -6.60%  (p=0.000 n=28+27)
NonZeroShifts/4/shrVU-8       7.79ns ± 2%  7.06ns ± 2%   -9.48%  (p=0.000 n=30+30)
NonZeroShifts/4/shlVU-8       7.82ns ± 1%  7.24ns ± 1%   -7.37%  (p=0.000 n=28+29)
NonZeroShifts/5/shrVU-8       8.90ns ± 3%  7.93ns ± 1%  -10.84%  (p=0.000 n=29+26)
NonZeroShifts/5/shlVU-8       8.68ns ± 1%  7.92ns ± 1%   -8.76%  (p=0.000 n=29+29)
NonZeroShifts/10/shrVU-8      14.4ns ± 1%  12.3ns ± 2%  -14.79%  (p=0.000 n=28+29)
NonZeroShifts/10/shlVU-8      14.1ns ± 1%  11.9ns ± 2%  -15.55%  (p=0.000 n=28+27)
NonZeroShifts/100/shrVU-8      118ns ± 1%    96ns ± 3%  -18.82%  (p=0.000 n=30+29)
NonZeroShifts/100/shlVU-8      120ns ± 2%    98ns ± 2%  -18.46%  (p=0.000 n=29+28)
NonZeroShifts/1000/shrVU-8    1.10µs ± 1%  0.88µs ± 2%  -19.63%  (p=0.000 n=29+30)
NonZeroShifts/1000/shlVU-8    1.10µs ± 2%  0.88µs ± 2%  -20.28%  (p=0.000 n=29+28)
NonZeroShifts/10000/shrVU-8   10.9µs ± 1%   8.7µs ± 1%  -19.78%  (p=0.000 n=28+27)
NonZeroShifts/10000/shlVU-8   10.9µs ± 2%   8.7µs ± 1%  -19.64%  (p=0.000 n=29+27)
NonZeroShifts/100000/shrVU-8   111µs ± 2%    90µs ± 2%  -19.39%  (p=0.000 n=28+29)
NonZeroShifts/100000/shlVU-8   113µs ± 2%    90µs ± 2%  -20.43%  (p=0.000 n=30+27)

The assembly version is still faster, unfortunately, but the gap is narrowing.
Speedup from pure Go to assembly:

name                          old time/op  new time/op  delta
NonZeroShifts/1/shrVU-8       4.39ns ± 1%  3.45ns ± 2%  -21.36%  (p=0.000 n=27+29)
NonZeroShifts/1/shlVU-8       4.10ns ± 2%  3.47ns ± 3%  -15.42%  (p=0.000 n=28+30)
NonZeroShifts/2/shrVU-8       5.63ns ± 2%  3.97ns ± 0%  -29.40%  (p=0.000 n=29+25)
NonZeroShifts/2/shlVU-8       5.14ns ± 1%  3.77ns ± 2%  -26.65%  (p=0.000 n=28+26)
NonZeroShifts/3/shrVU-8       6.35ns ± 2%  4.79ns ± 2%  -24.52%  (p=0.000 n=29+29)
NonZeroShifts/3/shlVU-8       6.25ns ± 1%  4.42ns ± 1%  -29.29%  (p=0.000 n=27+26)
NonZeroShifts/4/shrVU-8       7.06ns ± 2%  5.64ns ± 1%  -20.05%  (p=0.000 n=30+29)
NonZeroShifts/4/shlVU-8       7.24ns ± 1%  5.34ns ± 2%  -26.23%  (p=0.000 n=29+29)
NonZeroShifts/5/shrVU-8       7.93ns ± 1%  6.56ns ± 2%  -17.26%  (p=0.000 n=26+30)
NonZeroShifts/5/shlVU-8       7.92ns ± 1%  6.27ns ± 1%  -20.79%  (p=0.000 n=29+25)
NonZeroShifts/10/shrVU-8      12.3ns ± 2%  10.2ns ± 2%  -17.21%  (p=0.000 n=29+29)
NonZeroShifts/10/shlVU-8      11.9ns ± 2%  10.5ns ± 2%  -12.45%  (p=0.000 n=27+29)
NonZeroShifts/100/shrVU-8     95.9ns ± 3%  77.7ns ± 1%  -19.00%  (p=0.000 n=29+30)
NonZeroShifts/100/shlVU-8     97.5ns ± 2%  66.8ns ± 2%  -31.47%  (p=0.000 n=28+30)
NonZeroShifts/1000/shrVU-8     884ns ± 2%   705ns ± 1%  -20.17%  (p=0.000 n=30+28)
NonZeroShifts/1000/shlVU-8     880ns ± 2%   590ns ± 1%  -32.96%  (p=0.000 n=28+25)
NonZeroShifts/10000/shrVU-8   8.74µs ± 1%  7.34µs ± 3%  -15.94%  (p=0.000 n=27+30)
NonZeroShifts/10000/shlVU-8   8.73µs ± 1%  6.00µs ± 1%  -31.25%  (p=0.000 n=27+28)
NonZeroShifts/100000/shrVU-8  89.6µs ± 2%  75.5µs ± 2%  -15.80%  (p=0.000 n=29+29)
NonZeroShifts/100000/shlVU-8  89.6µs ± 2%  68.0µs ± 3%  -24.09%  (p=0.000 n=27+30)

Change-Id: I18f58d8f5513d737d9cdf09b8f9d14011ffe3958
Reviewed-on: https://go-review.googlesource.com/c/go/+/297050
Trust: Josh Bleecher Snyder <josharian@gmail.com>
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
 2021-03-11 19:11:46 +00:00
Paul E. Murphy
48ddf70128 cmd/asm,cmd/compile: support 5 operand RLWNM/RLWMI on ppc64 
These instructions are actually 5 argument opcodes as specified
by the ISA.  Prior to this patch, the MB and ME arguments were
merged into a single bitmask operand to workaround the limitations
of the ppc64 assembler backend.

This limitation no longer exists. Thus, we can pass operands for
these opcodes without having to merge the MB and ME arguments in
the assembler frontend or compiler backend.

Likewise, support for 4 operand variants is unchanged.

Change-Id: Ib086774f3581edeaadfd2190d652aaaa8a90daeb
Reviewed-on: https://go-review.googlesource.com/c/go/+/298750
Reviewed-by: Lynn Boger <laboger@linux.vnet.ibm.com>
Reviewed-by: Carlos Eduardo Seo <carlos.seo@linaro.org>
Trust: Carlos Eduardo Seo <carlos.seo@linaro.org>
 2021-03-09 20:35:41 +00:00
fanzha02
2b50ab2aee cmd/compile: optimize single-precision floating point square root 
Add generic rule to rewrite the single-precision square root expression
with one single-precision instruction. The optimization will reduce two
times of precision converting between double-precision and single-precision.

On arm64 flatform.

previous:
  FCVTSD F0, F0
  FSQRTD F0, F0
  FCVTDS F0, F0

optimized:
  FSQRTS S0, S0

And this patch adds the test case to check the correctness.

This patch refers to CL 241877, contributed by Alice Xu
(dianhong.xu@arm.com)

Change-Id: I6de5d02281c693017ac4bd4c10963dd55989bd7e
Reviewed-on: https://go-review.googlesource.com/c/go/+/276873
Trust: fannie zhang <Fannie.Zhang@arm.com>
Run-TryBot: fannie zhang <Fannie.Zhang@arm.com>
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Reviewed-by: Keith Randall <khr@golang.org>
 2021-03-02 06:38:07 +00:00
Egon Elbre
3ee32439b5 cmd/compile: ARM64 optimize []float64 and []float32 access 
Optimize load and store to []float64 and []float32.
Previously it used LSL instead of shifted register indexed load/store.

Before:

    LSL   $3, R0, R0
    FMOVD F0, (R1)(R0)

After:

    FMOVD F0, (R1)(R0<<3)

Fixes #42798

Change-Id: I0c0912140c3dce5aa6abc27097c0eb93833cc589
Reviewed-on: https://go-review.googlesource.com/c/go/+/273706
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
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Trust: Giovanni Bajo <rasky@develer.com>
 2021-02-24 19:49:08 +00:00
Alejandro García Montoro
bf48163e8f cmd/compile: add rule to coalesce writes 
The code generated when storing eight bytes loaded from memory created a
series of small writes instead of a single, large one. The specific
pattern of instructions generated stored 1 byte, then 2 bytes, then 4
bytes, and finally 1 byte.

The new rules match this specific pattern both for amd64 and for s390x,
and convert it into a single instruction to store the 8 bytes. arm64 and
ppc64le already generated the right code, but the new codegen test
covers also those architectures.

Fixes #41663

Change-Id: Ifb9b464be2d59c2ed5034acf7b9c3e473f344030
Reviewed-on: https://go-review.googlesource.com/c/go/+/280456
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
Trust: Josh Bleecher Snyder <josharian@gmail.com>
Trust: Jason A. Donenfeld <Jason@zx2c4.com>
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 2021-02-24 19:25:49 +00:00
Keith Randall
42cd40ee74 cmd/compile: improve bit test code 
Some bit test instruction generation stopped triggering after
the change to addressing modes. I suspect this was just because
ANDQload was being generated before the rewrite rules could discover
the BTQ. Fix that by decomposing the ANDQload when it is surrounded
by a TESTQ (thus re-enabling the BTQ rules).

Fixes #44228

Change-Id: I489b4a5a7eb01c65fc8db0753f8cec54097cadb2
Reviewed-on: https://go-review.googlesource.com/c/go/+/291749
Trust: Keith Randall <khr@golang.org>
Trust: Josh Bleecher Snyder <josharian@gmail.com>
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Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
 2021-02-23 18:02:48 +00:00
Cherry Zhang
401d7e5a24 [dev.regabi] cmd/compile: reserve X15 as zero register on AMD64 
In ABIInternal, reserve X15 as constant zero, and use it to zero
memory. (Maybe there can be more use of it?)

The register is zeroed when transition to ABIInternal from ABI0.

Caveat: using X15 generates longer instructions than using X0.
Maybe we want to use X0?

Change-Id: I12d5ee92a01fc0b59dad4e5ab023ac71bc2a8b7d
Reviewed-on: https://go-review.googlesource.com/c/go/+/288093
Trust: Cherry Zhang <cherryyz@google.com>
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Reviewed-by: David Chase <drchase@google.com>
 2021-02-03 22:44:53 +00:00
David Chase
9a19481acb [dev.regabi] cmd/compile: make ordering for InvertFlags more stable 
Current many architectures use a rule along the lines of

// Canonicalize the order of arguments to comparisons - helps with CSE.
((CMP|CMPW) x y) && x.ID > y.ID => (InvertFlags ((CMP|CMPW) y x))

to normalize comparisons as much as possible for CSE.  Replace the
ID comparison with something less variable across compiler changes.
This helps avoid spurious failures in some of the codegen-comparison
tests (though the current choice of comparison is sensitive to Op
ordering).

Two tests changed to accommodate modified instruction choice.

Change-Id: Ib35f450bd2bae9d4f9f7838ceaf7ec682bcf1e1a
Reviewed-on: https://go-review.googlesource.com/c/go/+/280155
Trust: David Chase <drchase@google.com>
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Reviewed-by: Cherry Zhang <cherryyz@google.com>
 2021-01-13 02:40:43 +00:00
Lynn Boger
0ae3b7cb74 cmd/compile: fix rules regression with shifts on PPC64 
Some rules for PPC64 were checking for a case
where a shift followed by an 'and' of a mask could
be lowered, depending on the format of the mask. The
function to verify if the mask was valid for this purpose
was not checking if the mask was 0 which we don't want to
allow. This case can happen if previous optimizations
resulted in that mask value.

This fixes isPPC64ValidShiftMask to check for a mask of 0 and return
false.

This also adds a codegen testcase to verify it doesn't try to
match the rules in the future.

Fixes #42610

Change-Id: I565d94e88495f51321ab365d6388c01e791b4dbb
Reviewed-on: https://go-review.googlesource.com/c/go/+/270358
Run-TryBot: Lynn Boger <laboger@linux.vnet.ibm.com>
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Trust: Lynn Boger <laboger@linux.vnet.ibm.com>
 2020-11-17 13:20:20 +00:00
Alberto Donizetti
7307e86afd test/codegen: go fmt 
Fixes #42445

Change-Id: I9653ef094dba2a1ac2e3daaa98279d10df17a2a1
Reviewed-on: https://go-review.googlesource.com/c/go/+/268257
Trust: Alberto Donizetti <alb.donizetti@gmail.com>
Trust: Martin Möhrmann <moehrmann@google.com>
Run-TryBot: Alberto Donizetti <alb.donizetti@gmail.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Martin Möhrmann <moehrmann@google.com>
 2020-11-08 12:19:55 +00:00
Michael Munday
854e892ce1 cmd/compile: optimize shift pairs and masks on s390x 
Optimize combinations of left and right shifts by a constant value
into a 'rotate then insert selected bits [into zero]' instruction.
Use the same instruction for contiguous masks since it has some
benefits over 'and immediate' (not restricted to 32-bits, does not
overwrite source register).

To keep the complexity of this change under control I've only
implemented 64 bit operations for now.

There are a lot more optimizations that can be done with this
instruction family. However, since their function overlaps with other
instructions we need to be somewhat careful not to break existing
optimization rules by creating optimization dead ends. This is
particularly true of the load/store merging rules which contain lots
of zero extensions and shifts.

This CL does interfere with the store merging rules when an operand
is shifted left before it is stored:

  binary.BigEndian.PutUint64(b, x << 1)

This is unfortunate but it's not critical and somewhat complex so
I plan to fix that in a follow up CL.

file      before    after     Δ       %
addr2line 4117446   4117282   -164    -0.004%
api       4945184   4942752   -2432   -0.049%
asm       4998079   4991891   -6188   -0.124%
buildid   2685158   2684074   -1084   -0.040%
cgo       4553732   4553394   -338    -0.007%
compile   19294446  19245070  -49376  -0.256%
cover     4897105   4891319   -5786   -0.118%
dist      3544389   3542785   -1604   -0.045%
doc       3926795   3927617   +822    +0.021%
fix       3302958   3293868   -9090   -0.275%
link      6546274   6543456   -2818   -0.043%
nm        4102021   4100825   -1196   -0.029%
objdump   4542431   4548483   +6052   +0.133%
pack      2482465   2416389   -66076  -2.662%
pprof     13366541  13363915  -2626   -0.020%
test2json 2829007   2761515   -67492  -2.386%
trace     10216164  10219684  +3520   +0.034%
vet       6773956   6773572   -384    -0.006%
total     107124151 106917891 -206260 -0.193%

Change-Id: I7591cce41e06867ba10a745daae9333513062746
Reviewed-on: https://go-review.googlesource.com/c/go/+/233317
Run-TryBot: Michael Munday <mike.munday@ibm.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Trust: Michael Munday <mike.munday@ibm.com>
 2020-11-06 10:45:31 +00:00
Cherry Zhang
0387bedadf cmd/compile: remove racefuncenterfp when it is not needed 
We already remove racefuncenter and racefuncexit if they are not
needed (i.e. the function doesn't have any other race  calls).
racefuncenterfp is like racefuncenter but used on LR machines.
Remove unnecessary racefuncenterfp as well.

Change-Id: I65edb00e19c6d9ab55a204cbbb93e9fb710559f1
Reviewed-on: https://go-review.googlesource.com/c/go/+/267099
Trust: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
 2020-11-02 03:03:16 +00:00
Paul E. Murphy
c3c6fbf314 cmd/compile: combine more 32 bit shift and mask operations on ppc64 
Combine (AND m (SRWconst x)) or (SRWconst (AND m x)) when mask m is
and the shift value produce constant which can be encoded into an
RLWINM instruction.

Combine (CLRLSLDI (SRWconst x)) if the combining of the underling rotate
masks produces a constant which can be encoded into RLWINM.

Likewise for (SLDconst (SRWconst x)) and (CLRLSDI (RLWINM x)).

Combine rotate word + and operations which can be encoded as a single
RLWINM/RLWNM instruction.

The most notable performance improvements arise from the crypto
benchmarks below (GOARCH=power8 on a ppc64le/linux):

pkg:golang.org/x/crypto/blowfish goos:linux goarch:ppc64le
ExpandKeyWithSalt                               52.2µs ± 0%    47.5µs ± 0%  -8.88%
ExpandKey                                       44.4µs ± 0%    40.3µs ± 0%  -9.15%

pkg:golang.org/x/crypto/ssh/internal/bcrypt_pbkdf goos:linux goarch:ppc64le
Key                                             57.6ms ± 0%    52.3ms ± 0%  -9.13%

pkg:golang.org/x/crypto/bcrypt goos:linux goarch:ppc64le
Equal                                           90.9ms ± 0%    82.6ms ± 0%  -9.13%
DefaultCost                                     91.0ms ± 0%    82.7ms ± 0%  -9.12%

Change-Id: I59a0ca29face38f4ab46e37124c32906f216c4ce
Reviewed-on: https://go-review.googlesource.com/c/go/+/260798
Run-TryBot: Carlos Eduardo Seo <carlos.seo@linaro.com>
TryBot-Result: Go Bot <gobot@golang.org>
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Reviewed-by: Carlos Eduardo Seo <carlos.seo@linaro.com>
Trust: Lynn Boger <laboger@linux.vnet.ibm.com>
 2020-10-27 18:33:20 +00:00
Keith Randall
04b8a9fea5 all: implement GO386=softfloat 
Backstop support for non-sse2 chips now that 387 is gone.

RELNOTE=yes

Change-Id: Ib10e69c4a3654c15a03568f93393437e1939e013
Reviewed-on: https://go-review.googlesource.com/c/go/+/260017
Trust: Keith Randall <khr@golang.org>
Run-TryBot: Keith Randall <khr@golang.org>
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Reviewed-by: Ian Lance Taylor <iant@golang.org>
 2020-10-06 22:49:38 +00:00
Keith Randall
fe2cfb74ba all: drop 387 support 
My last 387 CL. So sad ... ... ... ... not!

Fixes #40255

Change-Id: I8d4ddb744b234b8adc735db2f7c3c7b6d8bbdfa4
Reviewed-on: https://go-review.googlesource.com/c/go/+/258957
Trust: Keith Randall <khr@golang.org>
Run-TryBot: Keith Randall <khr@golang.org>
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Reviewed-by: Cherry Zhang <cherryyz@google.com>
 2020-10-02 00:00:51 +00:00
Lynn Boger
cc2a5cf4b8 cmd/compile,cmd/internal/obj/ppc64: fix some shift rules due to a regression 
A recent change to improve shifts was generating some
invalid cases when the rule was based on an AND. The
extended mnemonics CLRLSLDI and CLRLSLWI only allow
certain values for the operands and in the mask case
those values were not being checked properly. This
adds a check to those rules to verify that the
'b' and 'n' values used when an AND was part of the rule
have correct values.

There was a bug in some diag messages in asm9. The
message expected 3 values but only provided 2. Those are
corrected here also.

The test/codegen/shift.go was updated to add a few more
cases to check for the case mentioned here.

Some of the comments that mention the order of operands
in these extended mnemonics were wrong and those have been
corrected.

Fixes #41683.

Change-Id: If5bb860acaa5051b9e0cd80784b2868b85898c31
Reviewed-on: https://go-review.googlesource.com/c/go/+/258138
Run-TryBot: Lynn Boger <laboger@linux.vnet.ibm.com>
Reviewed-by: Paul Murphy <murp@ibm.com>
Reviewed-by: Carlos Eduardo Seo <carlos.seo@gmail.com>
TryBot-Result: Go Bot <gobot@golang.org>
Trust: Lynn Boger <laboger@linux.vnet.ibm.com>
 2020-10-01 18:51:18 +00:00
Lynn Boger
a424f6e45e cmd/asm,cmd/compile,cmd/internal/obj/ppc64: add extswsli support on power9 
This adds support for the extswsli instruction which combines
extsw followed by a shift.

New benchmark demonstrates the improvement:
name      old time/op  new time/op  delta
ExtShift  1.34µs ± 0%  1.30µs ± 0%  -3.15%  (p=0.057 n=4+3)

Change-Id: I21b410676fdf15d20e0cbbaa75d7c6dcd3bbb7b0
Reviewed-on: https://go-review.googlesource.com/c/go/+/257017
Run-TryBot: Lynn Boger <laboger@linux.vnet.ibm.com>
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Trust: Lynn Boger <laboger@linux.vnet.ibm.com>
 2020-09-28 18:13:48 +00:00
Lynn Boger
967465da29 cmd/compile: use combined shifts to improve array addressing on ppc64x 
This change adds rules to find pairs of instructions that can
be combined into a single shifts. These instruction sequences
are common in array addressing within loops. Improvements can
be seen in many crypto packages and the hash packages.

These are based on the extended mnemonics found in the ISA
sections C.8.1 and C.8.2.

Some rules in PPC64.rules were moved because the ordering prevented
some matching.

The following results were generated on power9.

hash/crc32:
    CRC32/poly=Koopman/size=40/align=0          195ns ± 0%     163ns ± 0%  -16.41%
    CRC32/poly=Koopman/size=40/align=1          200ns ± 0%     163ns ± 0%  -18.50%
    CRC32/poly=Koopman/size=512/align=0        1.98µs ± 0%    1.67µs ± 0%  -15.46%
    CRC32/poly=Koopman/size=512/align=1        1.98µs ± 0%    1.69µs ± 0%  -14.80%
    CRC32/poly=Koopman/size=1kB/align=0        3.90µs ± 0%    3.31µs ± 0%  -15.27%
    CRC32/poly=Koopman/size=1kB/align=1        3.85µs ± 0%    3.31µs ± 0%  -14.15%
    CRC32/poly=Koopman/size=4kB/align=0        15.3µs ± 0%    13.1µs ± 0%  -14.22%
    CRC32/poly=Koopman/size=4kB/align=1        15.4µs ± 0%    13.1µs ± 0%  -14.79%
    CRC32/poly=Koopman/size=32kB/align=0        137µs ± 0%     105µs ± 0%  -23.56%
    CRC32/poly=Koopman/size=32kB/align=1        137µs ± 0%     105µs ± 0%  -23.53%

crypto/rc4:
    RC4_128    733ns ± 0%    650ns ± 0%  -11.32%  (p=1.000 n=1+1)
    RC4_1K    5.80µs ± 0%   5.17µs ± 0%  -10.89%  (p=1.000 n=1+1)
    RC4_8K    45.7µs ± 0%   40.8µs ± 0%  -10.73%  (p=1.000 n=1+1)

crypto/sha1:
    Hash8Bytes       635ns ± 0%     613ns ± 0%   -3.46%  (p=1.000 n=1+1)
    Hash320Bytes    2.30µs ± 0%    2.18µs ± 0%   -5.38%  (p=1.000 n=1+1)
    Hash1K          5.88µs ± 0%    5.38µs ± 0%   -8.62%  (p=1.000 n=1+1)
    Hash8K          42.0µs ± 0%    37.9µs ± 0%   -9.75%  (p=1.000 n=1+1)

There are other improvements found in golang.org/x/crypto which are all in the
range of 5-15%.

Change-Id: I193471fbcf674151ffe2edab212799d9b08dfb8c
Reviewed-on: https://go-review.googlesource.com/c/go/+/252097
Trust: Lynn Boger <laboger@linux.vnet.ibm.com>
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TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Carlos Eduardo Seo <cseo@linux.vnet.ibm.com>
 2020-09-17 12:37:40 +00:00
Cuong Manh Le
27a30186ab cmd/compile,runtime: skip zero'ing order array for select statements 
The order array was zero initialized by the compiler, but ends up being
overwritten by the runtime anyway.

So let the runtime takes full responsibility for initializing, save us
one instruction per select.

Fixes #40399

Change-Id: Iec1eca27ad7180d4fcb3cc9ef97348206b7fe6b8
Reviewed-on: https://go-review.googlesource.com/c/go/+/251517
Run-TryBot: Cuong Manh Le <cuong.manhle.vn@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
 2020-08-29 08:02:52 +00:00
Paul E. Murphy
7615b20d06 cmd/compile: generate subfic on ppc64 
This merges an lis + subf into subfic, and for 32b constants
lwa + subf into oris + ori + subf.

The carry bit is no longer used in code generation, therefore
I think we can clobber it as needed.  Note, lowered borrow/carry
arithmetic is self-contained and thus is not affected.

A few extra rules are added to ensure early transformations to
SUBFCconst don't trip up earlier rules, fold constant operations,
or otherwise simplify lowering.  Likewise, tests are added to
ensure all rules are hit.  Generic constant folding catches
trivial cases, however some lowering rules insert arithmetic
which can introduce new opportunities (e.g BitLen or Slicemask).

I couldn't find a specific benchmark to demonstrate noteworthy
improvements, but this is generating subfic in many of the default
bent test binaries, so we are at least saving a little code space.

Change-Id: Iad7c6e5767eaa9dc24dc1c989bd1c8cfe1982012
Reviewed-on: https://go-review.googlesource.com/c/go/+/249461
Run-TryBot: Lynn Boger <laboger@linux.vnet.ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Carlos Eduardo Seo <cseo@linux.vnet.ibm.com>
 2020-08-27 20:10:15 +00:00
fanzha02
d556c251a1 cmd/compile: add more generic rewrite rules to reassociate (op (op y C) x|C) 
With this patch, opt pass can expose more obvious constant-folding
opportunites.

Example:
func test(i int) int {return (i+8)-(i+4)}

The previous version:
  MOVD	"".i(FP), R0
  ADD	$8, R0, R1
  ADD	$4, R0, R0
  SUB	R0, R1, R0
  MOVD	R0, "".~r1+8(FP)
  RET	(R30)

The optimized version:
  MOVD	$4, R0
  MOVD	R0, "".~r1+8(FP)
  RET	(R30)

This patch removes some existing reassociation rules, such as "x+(z-C)",
because the current generic rewrite rules will canonicalize "x-const"
to "x+(-const)", making "x+(z-C)" equal to "x+(z+(-C))".

This patch also adds test cases.

Change-Id: I857108ba0b5fcc18a879eeab38e2551bc4277797
Reviewed-on: https://go-review.googlesource.com/c/go/+/237137
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
 2020-08-24 14:52:54 +00:00
Agniva De Sarker
8acbe4c0b3 cmd/compile: optimize unsigned comparisons with 0/1 on wasm 
Updates #21439

Change-Id: I0fbcde6e0c2fc368fe686b271670f9d8be4a7900
Reviewed-on: https://go-review.googlesource.com/c/go/+/247557
Run-TryBot: Agniva De Sarker <agniva.quicksilver@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Richard Musiol <neelance@gmail.com>
 2020-08-22 12:35:47 +00:00
diaxu01
01aad9ea93 cmd/compile: Optimize ARM64's code with EON 
This patch fuses pattern '(MVN (XOR x y))' into '(EON x y)'.

Change-Id: I269c98ce198d51a4945ce8bd0e1024acbd1b7609
Reviewed-on: https://go-review.googlesource.com/c/go/+/239638
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
 2020-08-19 16:47:14 +00:00
Paul E. Murphy
e7c7ce646f cmd/compile: combine multiply/add into maddld on ppc64le/power9 
Add a new lowering rule to match and replace such instances
with the MADDLD instruction available on power9 where
possible.

Likewise, this plumbs in a new ppc64 ssa opcode to house
the newly generated MADDLD instructions.

When testing ed25519, this reduced binary size by 936B.
Similarly, MADDLD combination occcurs in a few other less
obvious cases such as division by constant.

Testing of golang.org/x/crypto/ed25519 shows non-trivial
speedup during keygeneration:

name           old time/op  new time/op  delta
KeyGeneration  65.2µs ± 0%  63.1µs ± 0%  -3.19%
Signing        64.3µs ± 0%  64.4µs ± 0%  +0.16%
Verification    147µs ± 0%   147µs ± 0%  +0.11%

Similarly, this test binary has shrunk by 66488B.

Change-Id: I077aeda7943119b41f07e4e62e44a648f16e4ad0
Reviewed-on: https://go-review.googlesource.com/c/go/+/248723
Run-TryBot: Lynn Boger <laboger@linux.vnet.ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Lynn Boger <laboger@linux.vnet.ibm.com>
 2020-08-18 21:09:30 +00:00
Michael Munday
6e876f1985 cmd/compile: clean up and optimize s390x multiplication rules 
Some of the existing optimizations aren't triggered because they
are handled by the generic rules so this CL removes them. Also
some constraints were copied without much thought from the amd64
rules and they don't make sense on s390x, so we remove those
constraints.

Finally, add a 'multiply by the sum of two powers of two'
optimization. This makes sense on s390x as shifts are low latency
and can also sometimes be optimized further (especially if we add
support for RISBG instructions).

name                   old time/op  new time/op  delta
IntMulByConst/3-8      1.70ns ±11%  1.10ns ± 5%  -35.26%  (p=0.000 n=10+10)
IntMulByConst/5-8      1.64ns ± 7%  1.10ns ± 4%  -32.94%  (p=0.000 n=10+9)
IntMulByConst/12-8     1.65ns ± 6%  1.20ns ± 4%  -27.16%  (p=0.000 n=10+9)
IntMulByConst/120-8    1.66ns ± 4%  1.22ns ±13%  -26.43%  (p=0.000 n=10+10)
IntMulByConst/-120-8   1.65ns ± 7%  1.19ns ± 4%  -28.06%  (p=0.000 n=9+10)
IntMulByConst/65537-8  0.86ns ± 9%  1.12ns ±12%  +30.41%  (p=0.000 n=10+10)
IntMulByConst/65538-8  1.65ns ± 5%  1.23ns ± 5%  -25.11%  (p=0.000 n=10+10)

Change-Id: Ib196e6bff1e97febfd266134d0a2b2a62897989f
Reviewed-on: https://go-review.googlesource.com/c/go/+/248937
Run-TryBot: Michael Munday <mike.munday@ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
 2020-08-18 15:39:44 +00:00
Junchen Li
06337823ef cmd/compile: optimize unsigned comparisons to 0/1 on arm64 
For an unsigned integer, it's useful to convert its order test with 0/1
to its equality test with 0. We can save a comparison instruction that
followed by a conditional branch on arm64 since it supports
compare-with-zero-and-branch instructions. For example,

  if x > 0 { ... } else { ... }

the original version:
  CMP $0, R0
  BLS 9

the optimized version:
  CBZ R0, 8

Updates #21439

Change-Id: Id1de6f865f6aa72c5d45b29f7894818857288425
Reviewed-on: https://go-review.googlesource.com/c/go/+/246857
Reviewed-by: Keith Randall <khr@golang.org>
 2020-08-18 04:09:13 +00:00
Keith Randall
ef9c8a38ad cmd/compile: don't rewrite (CMP (AND x y) 0) to TEST if AND has other uses 
If the AND has other uses, we end up saving an argument to the AND
in another register, so we can use it for the TEST. No point in doing that.

Change-Id: I73444a6aeddd6f55e2328ce04d77c3e6cf4a83e0
Reviewed-on: https://go-review.googlesource.com/c/go/+/241280
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
 2020-08-17 22:00:44 +00:00
Junchen Li
e30fbe3757 cmd/compile: optimize unsigned comparisons to 0 
There are some architecture-independent rules in #21439, since an
unsigned integer >= 0 is always true and < 0 is always false. This CL
adds these optimizations to generic rules.

Updates #21439

Change-Id: Iec7e3040b761ecb1e60908f764815fdd9bc62495
Reviewed-on: https://go-review.googlesource.com/c/go/+/246617
Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
 2020-08-17 20:06:35 +00:00
Keith Randall
c4fed25553 cmd/compile: add floating point load+op operations to addressing modes pass 
They were missed as part of the refactoring to use a separate
addressing modes pass.

Fixes #40426

Change-Id: Ie0418b2fac4ba1ffe720644ac918f6d728d5e420
Reviewed-on: https://go-review.googlesource.com/c/go/+/244859
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
 2020-07-27 18:24:32 +00:00
Xiangdong Ji
e031318ca6 cmd/compile: ARM comparisons with 0 incorrect on overflow 
Some ARM rewriting rules convert 'comparing to zero' conditions of if
statements to a simplified version utilizing CMN and CMP instructions to
branch over condition flags, in order to save one Add or Sub caculation.

Such optimizations lead to wrong branching in case an overflow/underflow
occurs when executing CMN or CMP.

Fix the issue by introducing new block opcodes that don't honor the
overflow/underflow flag:

  Block-Op         Meaning                   ARM condition codes
  1. LTnoov        less than                 MI
  2. GEnoov        greater than or equal     PL
  3. LEnoov        less than or equal        MI || EQ
  4. GTnoov        greater than              NEQ & PL

The patch also adds a few test cases to cover scenarios that are specific
to ARM and fine-tunes the code generation tests for 'x-const'.

For more details please refer to the previous fix on 64-bit ARM:
  https://go-review.googlesource.com/c/go/+/233097

Go1 perf, 'old' is the non-optimized version, that is removing all concerned
rewriting rules.

name                     old time/op    new time/op     delta
BinaryTree17-8              7.73s ± 0%      7.81s ± 0%  +0.97%  (p=0.000 n=7+8)
Fannkuch11-8                7.06s ± 0%      7.00s ± 0%  -0.83%  (p=0.000 n=8+8)
FmtFprintfEmpty-8           181ns ± 1%      183ns ± 1%  +1.31%  (p=0.001 n=8+8)
FmtFprintfString-8          319ns ± 1%      325ns ± 2%  +1.71%  (p=0.009 n=7+8)
FmtFprintfInt-8             358ns ± 1%      359ns ± 1%    ~     (p=0.293 n=7+7)
FmtFprintfIntInt-8          459ns ± 3%      456ns ± 1%    ~     (p=0.869 n=8+8)
FmtFprintfPrefixedInt-8     535ns ± 4%      538ns ± 4%    ~     (p=0.572 n=8+8)
FmtFprintfFloat-8          1.01µs ± 2%     1.01µs ± 2%    ~     (p=0.625 n=8+8)
FmtManyArgs-8              1.93µs ± 2%     1.93µs ± 1%    ~     (p=0.979 n=8+7)
GobDecode-8                16.1ms ± 1%     16.5ms ± 1%  +2.32%  (p=0.000 n=8+8)
GobEncode-8                15.9ms ± 0%     15.8ms ± 1%  -1.00%  (p=0.000 n=8+7)
Gzip-8                      690ms ± 1%      670ms ± 0%  -2.90%  (p=0.000 n=8+8)
Gunzip-8                    109ms ± 1%      109ms ± 1%    ~     (p=0.694 n=7+8)
HTTPClientServer-8          149µs ± 3%      146µs ± 2%  -1.70%  (p=0.028 n=8+8)
JSONEncode-8               50.5ms ± 1%     49.2ms ± 0%  -2.60%  (p=0.001 n=7+7)
JSONDecode-8                135ms ± 2%      137ms ± 1%    ~     (p=0.054 n=8+7)
Mandelbrot200-8             951ms ± 0%      952ms ± 0%    ~     (p=0.852 n=6+8)
GoParse-8                  9.47ms ± 1%     9.66ms ± 1%  +2.01%  (p=0.000 n=8+8)
RegexpMatchEasy0_32-8       288ns ± 2%      277ns ± 2%  -3.61%  (p=0.000 n=8+8)
RegexpMatchEasy0_1K-8      1.66µs ± 1%     1.69µs ± 2%  +2.21%  (p=0.001 n=7+7)
RegexpMatchEasy1_32-8       334ns ± 1%      305ns ± 2%  -8.86%  (p=0.000 n=8+8)
RegexpMatchEasy1_1K-8      2.14µs ± 2%     2.15µs ± 0%    ~     (p=0.099 n=8+8)
RegexpMatchMedium_32-8     13.3ns ± 1%     13.3ns ± 0%    ~     (p=1.000 n=7+7)
RegexpMatchMedium_1K-8     81.1µs ± 3%     80.7µs ± 1%    ~     (p=0.955 n=7+8)
RegexpMatchHard_32-8       4.26µs ± 0%     4.26µs ± 0%    ~     (p=0.933 n=7+8)
RegexpMatchHard_1K-8        124µs ± 0%      124µs ± 0%  +0.31%  (p=0.000 n=8+8)
Revcomp-8                  14.7ms ± 2%     14.5ms ± 1%  -1.66%  (p=0.003 n=8+8)
Template-8                  197ms ± 2%      200ms ± 3%  +1.62%  (p=0.021 n=8+8)
TimeParse-8                1.33µs ± 1%     1.30µs ± 1%  -1.86%  (p=0.002 n=8+8)
TimeFormat-8               3.04µs ± 1%     3.02µs ± 0%  -0.60%  (p=0.000 n=8+8)

name                     old speed      new speed       delta
GobDecode-8              47.6MB/s ± 1%   46.5MB/s ± 1%  -2.28%  (p=0.000 n=8+8)
GobEncode-8              48.1MB/s ± 0%   48.6MB/s ± 1%  +1.02%  (p=0.000 n=8+7)
Gzip-8                   28.1MB/s ± 1%   29.0MB/s ± 0%  +2.97%  (p=0.000 n=8+8)
Gunzip-8                  178MB/s ± 1%    179MB/s ± 2%    ~     (p=0.694 n=7+8)
JSONEncode-8             38.4MB/s ± 1%   39.4MB/s ± 0%  +2.67%  (p=0.001 n=7+7)
JSONDecode-8             14.3MB/s ± 2%   14.2MB/s ± 1%  -0.81%  (p=0.043 n=8+7)
GoParse-8                6.12MB/s ± 1%   5.99MB/s ± 1%  -2.00%  (p=0.000 n=8+8)
RegexpMatchEasy0_32-8     111MB/s ± 2%    115MB/s ± 2%  +3.77%  (p=0.000 n=8+8)
RegexpMatchEasy0_1K-8     618MB/s ± 1%    604MB/s ± 2%  -2.16%  (p=0.001 n=7+7)
RegexpMatchEasy1_32-8    95.7MB/s ± 1%  105.1MB/s ± 2%  +9.76%  (p=0.000 n=8+8)
RegexpMatchEasy1_1K-8     479MB/s ± 2%    477MB/s ± 0%    ~     (p=0.105 n=8+8)
RegexpMatchMedium_32-8   75.2MB/s ± 1%   75.2MB/s ± 0%    ~     (p=0.247 n=7+7)
RegexpMatchMedium_1K-8   12.6MB/s ± 3%   12.7MB/s ± 1%    ~     (p=0.538 n=7+8)
RegexpMatchHard_32-8     7.52MB/s ± 0%   7.52MB/s ± 0%    ~     (p=0.968 n=7+8)
RegexpMatchHard_1K-8     8.26MB/s ± 0%   8.24MB/s ± 0%  -0.30%  (p=0.001 n=8+8)
Revcomp-8                 173MB/s ± 2%    176MB/s ± 1%  +1.68%  (p=0.003 n=8+8)
Template-8               9.85MB/s ± 2%   9.69MB/s ± 3%  -1.59%  (p=0.021 n=8+8)

Fixes   #39303
Updates #38740

Change-Id: I0a5f87bfda679f66414c0041ace2ca2e28363f36
Reviewed-on: https://go-review.googlesource.com/c/go/+/236637
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
 2020-06-09 15:50:33 +00:00
Xiangdong Ji
e8f5a33191 cmd/compile: fix incorrect rewriting to if condition 
Some ARM64 rewriting rules convert 'comparing to zero' conditions of if
statements to a simplified version utilizing CMN and CMP instructions to
branch over condition flags, in order to save one Add or Sub caculation.

Such optimizations lead to wrong branching in case an overflow/underflow
occurs when executing CMN or CMP.

Fix the issue by introducing new block opcodes that don't honor the
overflow/underflow flag, in the following categories:

  Block-Op        Meaning                   ARM condition codes
  1. LTnoov        less than                 MI
  2. GEnoov        greater than or equal     PL
  3. LEnoov        less than or equal        MI || EQ
  4. GTnoov        greater than              NEQ & PL

The backend generates two consecutive branch instructions for 'LEnoov'
and 'GTnoov' to model their expected behavior. A slight change to 'gc'
and amd64/386 backends is made to unify the code generation.

Add a test 'TestCondRewrite' as justification, it covers 32 incorrect rules
identified on arm64, more might be needed on other arches, like 32-bit arm.

Add two benchmarks profiling the aforementioned category 1&2 and category
3&4 separetely, we expect the first two categories will show performance
improvement and the second will not result in visible regression compared with
the non-optimized version.

This change also updates TestFormats to support using %#x.

Examples exhibiting where does the issue come from:
  1: 'if x + 3 < 0' might be converted to:
  before:
    CMN $3, R0
    BGE <else branch> // wrong branch is taken if 'x+3' overflows
  after:
    CMN $3, R0
    BPL <else branch>

  2: 'if y - 3 > 0' might be converted to:
  before:
    CMP $3, R0
    BLE <else branch> // wrong branch is taken if 'y-3' underflows
  after:
    CMP $3, R0
    BMI <else branch>
    BEQ <else branch>

Benchmark data from different kinds of arm64 servers, 'old' is the non-optimized
version (not the parent commit), generally the optimization version outperforms.

S1:
name                    old time/op  new time/op  delta
CondRewrite/SoloJump  13.6ns ± 0%  12.9ns ± 0%  -5.15%  (p=0.000 n=10+10)
CondRewrite/CombJump  13.8ns ± 1%  12.9ns ± 0%  -6.32%  (p=0.000 n=10+10)

S2:
name                     old time/op  new time/op  delta
CondRewrite/SoloJump  11.6ns ± 0%  10.9ns ± 0%  -6.03%  (p=0.000 n=10+10)
CondRewrite/CombJump  11.4ns ± 0%  10.8ns ± 1%  -5.53%  (p=0.000 n=10+10)

S3:
name                     old time/op  new time/op  delta
CondRewrite/SoloJump  7.36ns ± 0%  7.50ns ± 0%  +1.79%  (p=0.000 n=9+10)
CondRewrite/CombJump  7.35ns ± 0%  7.75ns ± 0%  +5.51%  (p=0.000 n=8+9)

S4:
name                      old time/op  new time/op  delta
CondRewrite/SoloJump-224  11.5ns ± 1%  10.9ns ± 0%  -4.97%  (p=0.000 n=10+10)
CondRewrite/CombJump-224  11.9ns ± 0%  11.5ns ± 0%  -2.95%  (p=0.000 n=10+10)

S5:
name                     old time/op  new time/op  delta
CondRewrite/SoloJump  10.0ns ± 0%  10.0ns ± 0%  -0.45%  (p=0.000 n=9+10)
CondRewrite/CombJump  9.93ns ± 0%  9.77ns ± 0%  -1.53%  (p=0.000 n=10+9)

Go1 perf. data:

name                     old time/op    new time/op    delta
BinaryTree17              6.29s ± 1%     6.30s ± 1%    ~     (p=1.000 n=5+5)
Fannkuch11                5.40s ± 0%     5.40s ± 0%    ~     (p=0.841 n=5+5)
FmtFprintfEmpty          97.9ns ± 0%    98.9ns ± 3%    ~     (p=0.937 n=4+5)
FmtFprintfString          171ns ± 3%     171ns ± 2%    ~     (p=0.754 n=5+5)
FmtFprintfInt             212ns ± 0%     217ns ± 6%  +2.55%  (p=0.008 n=5+5)
FmtFprintfIntInt          296ns ± 1%     297ns ± 2%    ~     (p=0.516 n=5+5)
FmtFprintfPrefixedInt     371ns ± 2%     374ns ± 7%    ~     (p=1.000 n=5+5)
FmtFprintfFloat           435ns ± 1%     439ns ± 2%    ~     (p=0.056 n=5+5)
FmtManyArgs              1.37µs ± 1%    1.36µs ± 1%    ~     (p=0.730 n=5+5)
GobDecode                14.6ms ± 4%    14.4ms ± 4%    ~     (p=0.690 n=5+5)
GobEncode                11.8ms ±20%    11.6ms ±15%    ~     (p=1.000 n=5+5)
Gzip                      507ms ± 0%     491ms ± 0%  -3.22%  (p=0.008 n=5+5)
Gunzip                   73.8ms ± 0%    73.9ms ± 0%    ~     (p=0.690 n=5+5)
HTTPClientServer          116µs ± 0%     116µs ± 0%    ~     (p=0.686 n=4+4)
JSONEncode               21.8ms ± 1%    21.6ms ± 2%    ~     (p=0.151 n=5+5)
JSONDecode                104ms ± 1%     103ms ± 1%  -1.08%  (p=0.016 n=5+5)
Mandelbrot200            9.53ms ± 0%    9.53ms ± 0%    ~     (p=0.421 n=5+5)
GoParse                  7.55ms ± 1%    7.51ms ± 1%    ~     (p=0.151 n=5+5)
RegexpMatchEasy0_32       158ns ± 0%     158ns ± 0%    ~     (all equal)
RegexpMatchEasy0_1K       606ns ± 1%     608ns ± 3%    ~     (p=0.937 n=5+5)
RegexpMatchEasy1_32       143ns ± 0%     144ns ± 1%    ~     (p=0.095 n=5+4)
RegexpMatchEasy1_1K       927ns ± 2%     944ns ± 2%    ~     (p=0.056 n=5+5)
RegexpMatchMedium_32     16.0ns ± 0%    16.0ns ± 0%    ~     (all equal)
RegexpMatchMedium_1K     69.3µs ± 2%    69.7µs ± 0%    ~     (p=0.690 n=5+5)
RegexpMatchHard_32       3.73µs ± 0%    3.73µs ± 1%    ~     (p=0.984 n=5+5)
RegexpMatchHard_1K        111µs ± 1%     110µs ± 0%    ~     (p=0.151 n=5+5)
Revcomp                   1.91s ±47%     1.77s ±68%    ~     (p=1.000 n=5+5)
Template                  138ms ± 1%     138ms ± 1%    ~     (p=1.000 n=5+5)
TimeParse                 787ns ± 2%     785ns ± 1%    ~     (p=0.540 n=5+5)
TimeFormat                729ns ± 1%     726ns ± 1%    ~     (p=0.151 n=5+5)

Updates #38740
Change-Id: I06c604874acdc1e63e66452dadee5df053045222
Reviewed-on: https://go-review.googlesource.com/c/go/+/233097
Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: Keith Randall <khr@golang.org>
 2020-05-29 15:39:54 +00:00
Keith Randall
2cb10d42b7 cmd/compile: in prove, zero right shifts of positive int by #bits - 1 
Taking over Zach's CL 212277. Just cleaned up and added a test.

For a positive, signed integer, an arithmetic right shift of count
(bit-width - 1) equals zero. e.g. int64(22) >> 63 -> 0. This CL makes
prove replace these right shifts with a zero-valued constant.

These shifts may arise in source code explicitly, but can also be
created by the generic rewrite of signed division by a power of 2.
// Signed divide by power of 2.
// n / c =       n >> log(c) if n >= 0
//       = (n+c-1) >> log(c) if n < 0
// We conditionally add c-1 by adding n>>63>>(64-log(c))
	(first shift signed, second shift unsigned).
(Div64 <t> n (Const64 [c])) && isPowerOfTwo(c) ->
  (Rsh64x64
    (Add64 <t> n (Rsh64Ux64 <t>
    	(Rsh64x64 <t> n (Const64 <typ.UInt64> [63]))
	(Const64 <typ.UInt64> [64-log2(c)])))
    (Const64 <typ.UInt64> [log2(c)]))

If n is known to be positive, this rewrite includes an extra Add and 2
extra Rsh. This CL will allow prove to replace one of the extra Rsh with
a 0. That replacement then allows lateopt to remove all the unneccesary
fixups from the generic rewrite.

There is a rewrite rule to handle this case directly:
(Div64 n (Const64 [c])) && isNonNegative(n) && isPowerOfTwo(c) ->
	(Rsh64Ux64 n (Const64 <typ.UInt64> [log2(c)]))
But this implementation of isNonNegative really only handles constants
and a few special operations like len/cap. The division could be
handled if the factsTable version of isNonNegative were available.
Unfortunately, the first opt pass happens before prove even has a
chance to deduce the numerator is non-negative, so the generic rewrite
has already fired and created the extra Ops discussed above.

Fixes #36159

By Printf count, this zeroes 137 right shifts when building std and cmd.

Change-Id: Iab486910ac9d7cfb86ace2835456002732b384a2
Reviewed-on: https://go-review.googlesource.com/c/go/+/232857
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
 2020-05-11 16:23:52 +00:00
Martin Möhrmann
6ed4661807 cmd/compile: optimize make+copy pattern to avoid memclr 
match:
 m = make([]T, x); copy(m, s)
for pointer free T and x==len(s) rewrite to:
 m = mallocgc(x*elemsize(T), nil, false); memmove(&m, &s, x*elemsize(T))
otherwise rewrite to:
 m = makeslicecopy([]T, x, s)

This avoids memclear and shading of pointers in the newly created slice
before the copy.

With this CL "s" is only be allowed to bev a variable and not a more
complex expression. This restriction could be lifted in future versions
of this optimization when it can be proven that "s" is not referencing "m".

Triggers 450 times during make.bash..
Reduces go binary size by ~8 kbyte.

name                           old time/op  new time/op  delta
MakeSliceCopy/mallocmove/Byte  71.1ns ± 1%  65.8ns ± 0%  -7.49%  (p=0.000 n=10+9)
MakeSliceCopy/mallocmove/Int   71.2ns ± 1%  66.0ns ± 0%  -7.27%  (p=0.000 n=10+8)
MakeSliceCopy/mallocmove/Ptr    104ns ± 4%    99ns ± 1%  -5.13%  (p=0.000 n=10+10)
MakeSliceCopy/makecopy/Byte    70.3ns ± 0%  68.0ns ± 0%  -3.22%  (p=0.000 n=10+9)
MakeSliceCopy/makecopy/Int     70.3ns ± 0%  68.5ns ± 1%  -2.59%  (p=0.000 n=9+10)
MakeSliceCopy/makecopy/Ptr      102ns ± 0%    99ns ± 1%  -2.97%  (p=0.000 n=9+9)
MakeSliceCopy/nilappend/Byte   75.4ns ± 0%  74.9ns ± 2%  -0.63%  (p=0.015 n=9+9)
MakeSliceCopy/nilappend/Int    75.6ns ± 0%  76.4ns ± 3%    ~     (p=0.245 n=9+10)
MakeSliceCopy/nilappend/Ptr     107ns ± 0%   108ns ± 1%  +0.93%  (p=0.005 n=9+10)

Fixes #26252

Change-Id: Iec553dd1fef6ded16197216a472351c8799a8e71
Reviewed-on: https://go-review.googlesource.com/c/go/+/146719
Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: Martin Möhrmann <moehrmann@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
 2020-05-07 17:50:24 +00:00
Keith Randall
9ed0fb42e3 cmd/compile: add indexed memory modification ops to amd64 
name            old time/op  new time/op  delta
Modify-16        404ns ± 1%   365ns ± 1%  -9.73%  (p=0.000 n=10+10)
ConstModify-16   407ns ± 0%   385ns ± 2%  -5.56%  (p=0.000 n=9+10)

Seems to generally help generated code.

Binary size change is in the noise.

Change-Id: I57891bfaf0f7dfc5d143bb9f7ebafc7079d2614f
Reviewed-on: https://go-review.googlesource.com/c/go/+/228098
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
 2020-04-30 17:21:31 +00:00
Keith Randall
882ec701d2 cmd/compile: add indexed load+op operations to amd64 
name        old time/op  new time/op  delta
LoadAdd-16   545ns ± 0%   456ns ± 0%  -16.31%  (p=0.000 n=10+10)

Update #36468

Change-Id: I84f390d55490648fa1f58cdbc24fd74c4f1bc8c1
Reviewed-on: https://go-review.googlesource.com/c/go/+/227960
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
 2020-04-30 17:19:57 +00:00
Josh Bleecher Snyder
4a7e363288 cmd/compile: optimize Move with all-zero ro sym src to Zero 
We set up static symbols during walk that
we later make copies of to initialize local variables.
It is difficult to ascertain at that time exactly
when copying a symbol is profitable vs locally
initializing an autotmp.

During SSA, we are much better placed to optimize.
This change recognizes when we are copying from a
global readonly all-zero symbol and replaces it with
direct zeroing.

This often allows the all-zero symbol to be
deadcode eliminated at link time.
This is not ideal--it makes for large object files,
and longer link times--but it is the cleanest fix I could find.

This makes the final binary for the program in #38554
shrink from >500mb to ~2.2mb.

It also shrinks the standard binaries:

file      before    after     Δ       %
addr2line 4412496   4404304   -8192   -0.186%
buildid   2893816   2889720   -4096   -0.142%
cgo       4841048   4832856   -8192   -0.169%
compile   19926480  19922432  -4048   -0.020%
cover     5281816   5277720   -4096   -0.078%
link      6734648   6730552   -4096   -0.061%
nm        4366240   4358048   -8192   -0.188%
objdump   4755968   4747776   -8192   -0.172%
pprof     14653060  14612100  -40960  -0.280%
trace     11805940  11777268  -28672  -0.243%
vet       7185560   7181416   -4144   -0.058%
total     113588440 113465560 -122880 -0.108%

And not just by removing unnecessary symbols;
the program text shrinks a bit as well.

Fixes #38554

Change-Id: I8381ae6084ae145a5e0cd9410c451e52c0dc51c8
Reviewed-on: https://go-review.googlesource.com/c/go/+/229704
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Keith Randall <khr@golang.org>
 2020-04-24 23:58:10 +00:00
Josh Bleecher Snyder
e7c1873691 cmd/compile: optimize x & 1 != 0 to x & 1 on amd64 
Triggers a handful of times in std+cmd.

Change-Id: I9bb8ce9a5f8bae2547cb61157cd8f256e1b63e76
Reviewed-on: https://go-review.googlesource.com/c/go/+/229602
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
 2020-04-23 17:52:28 +00:00
Michael Munday
ab7a65f283 cmd/compile: clean up codegen for branch-on-carry on s390x 
This CL optimizes code that uses a carry from a function such as
bits.Add64 as the condition in an if statement. For example:

    x, c := bits.Add64(a, b, 0)
    if c != 0 {
        panic("overflow")
    }

Rather than converting the carry into a 0 or a 1 value and using
that as an input to a comparison instruction the carry flag is now
used as the input to a conditional branch directly. This typically
removes an ADD LOGICAL WITH CARRY instruction when user code is
doing overflow detection and is closer to the code that a user
would expect to generate.

Change-Id: I950431270955ab72f1b5c6db873b6abe769be0da
Reviewed-on: https://go-review.googlesource.com/c/go/+/219757
Run-TryBot: Michael Munday <mike.munday@ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
 2020-04-22 20:11:06 +00:00
Michael Munday
e464d7d797 cmd/compile: optimize comparisons with immediates on s390x 
When generating code for unsigned equals (==) and not equals (!=)
comparisons we currently, on s390x, always use signed comparisons.

This mostly works well, however signed comparisons on s390x sign
extend their immediates and unsigned comparisons zero extend them.
For compare-and-branch instructions which can only have 8-bit
immediates this significantly changes the range of immediate values
we can represent: [-128, 127] for signed comparisons and [0, 255]
for unsigned comparisons.

When generating equals and not equals checks we don't neet to worry
about whether the comparison is signed or unsigned. This CL
therefore adds rules to allow us to switch signedness for such
comparisons if it means that it brings a constant into range for an
8-bit immediate.

For example, a signed equals with an integer in the range [128, 255]
will now be implemented using an unsigned compare-and-branch
instruction rather than separate compare and branch instructions.

As part of this change I've also added support for adding a name
to block control values using the same `x:(...)` syntax we use for
value rules.

Triggers 792 times when compiling cmd and std.

Change-Id: I77fa80a128f0a8ce51a2888d1e384bd5e9b61a77
Reviewed-on: https://go-review.googlesource.com/c/go/+/228642
Run-TryBot: Michael Munday <mike.munday@ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
 2020-04-21 19:23:51 +00:00
alex-semenyuk
876c1feb7d test/codegen, runtime/pprof, runtime: apply fmt 
Change-Id: Ife4e065246729319c39e57a4fbd8e6f7b37724e1
GitHub-Last-Rev: e71803eaeb
GitHub-Pull-Request: golang/go#38527
Reviewed-on: https://go-review.googlesource.com/c/go/+/228901
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Tobias Klauser <tobias.klauser@gmail.com>
 2020-04-21 09:07:42 +00:00
Josh Bleecher Snyder
50b11318fe cmd/compile: use oneBit instead of isPowerOfTwo in bit optimization 
This optimization works on any integer with exactly one bit set.
This is identical to being a power of two, except in the
most negative number. Use oneBit instead.

The rule now triggers in a few more places in std+cmd,
in packages encoding/asn1, crypto/elliptic, and
vendor/golang.org/x/crypto/cryptobyte.

This change obviates the need for CL 222479
by doing this optimization consistently in the compiler.

Change-Id: I983c6235290fdc634fda5e11b10f1f8ce041272f
Reviewed-on: https://go-review.googlesource.com/c/go/+/229124
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
 2020-04-21 00:38:34 +00:00
David Chase
e4e192484b cmd/compile: split up the addressing mode on OpAMD64CMP*loadidx* always 
Benchmarking suggests that the combo instruction is notably slower,
at least in the places where we measure.

Updates #37955

Change-Id: I829f1975dd6edf38163128ba51d84604055512f4
Reviewed-on: https://go-review.googlesource.com/c/go/+/228157
Run-TryBot: David Chase <drchase@google.com>
Reviewed-by: Keith Randall <khr@golang.org>
 2020-04-15 18:09:14 +00:00
Lynn Boger
a1550d3ca3 cmd/compile: use isel with variable shifts on ppc64x 
This changes the code generated for variable length shift
counts to use isel instead of instructions that set and
read the carry flag.

This reduces the generated code for shifts like this
by 1 instruction and avoids the use of instructions to
set and read the carry flag.

This sequence can be found in strconv with these results
on power9:

Atof64Decimal                          71.6ns ± 0%  68.3ns ± 0%   -4.61%
Atof64Float                            95.3ns ± 0%  90.9ns ± 0%   -4.62%
Atof64FloatExp                          153ns ± 0%   149ns ± 0%   -2.61%
Atof64Big                               234ns ± 0%   232ns ± 0%   -0.85%
Atof64RandomBits                        348ns ± 0%   369ns ± 0%   +6.03%
Atof64RandomFloats                      262ns ± 0%   262ns ± 0%     ~
Atof32Decimal                          72.0ns ± 0%  68.2ns ± 0%   -5.28%
Atof32Float                            92.1ns ± 0%  87.1ns ± 0%   -5.43%
Atof32FloatExp                          159ns ± 0%   158ns ± 0%   -0.63%
Atof32Random                            194ns ± 0%   191ns ± 0%   -1.55%

Some tests in codegen/shift.go are enabled to verify the
expected instructions are generated.

Change-Id: I968715d10ada405a8c46132bf19b8ed9b85796d1
Reviewed-on: https://go-review.googlesource.com/c/go/+/227337
Run-TryBot: Lynn Boger <laboger@linux.vnet.ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
 2020-04-09 19:18:56 +00:00
Josh Bleecher Snyder
ade0811dc8 cmd/compile: handle some additional phis in shortcircuit 
Prior to this change, the shortcircuit pass could only
handle blocks containing only a single phi control value,
possibly wrapped in some OpNot and OpCopy values.

This change partially lifts this limitation.
It handles some cases in which the block contains other phi values.
This appears to happen most commonly in cases in which
the conditionals being checked involve the memory state,
in which case there is a phi memory value in the block.

The general idea here is to use the information we have about
the CFG to (1) move the other phi values into other blocks
and/or (2) rewrite uses of the other phi values in other blocks.

For example, consider this CFG:

p   q
 \ /
  b
 / \
t   u

And consider a phi value v in block b.
We'll write v = Phi(p: x, q: y) to say that v has value x corresponding
to inbound block p, and value y for block q.

We will rewrite this CFG to:

p    q
|   /
|  b
|/  \
t    u

What should we do with v?

Any uses of v in u can be replaced with y. Why?
If we are in block u, we came from b, and before that from q.
If prior to b we came from p, then we would have gone to t, not u.
Since we came from q, we know that v took the value y.

Uses of v in t are a bit more complicated.
It is going to end up being a phi value: Phi(p: ?, b: ?).

Suppose, after the rewrite, we came from block p.
Then, before the rewrite, we would have gone to b,
where v would have the value x.
So we have Phi(p: x, b: ?).

Suppose, after the rewrite, we came from block b.
Then we must have come from block q.
If we come from block q, v has value y.
So we have Phi(p: x, b: y).
Uses of v in t can thus be replaced with a new phi value,
with the same values as v, but with altered predecessors.

Similar reasoning can be employed to rewrite or replace
other uses of v elsewhere in the CFG, so that v itself can be eliminated,
and the CFG rewrite can proceed.

This change sets up the infrastructure for such optimizations
and adds a few cheap ones. All optimizations in this change depend
only on the shape of the CFG; future changes may also depend on where
v's uses are. That analysis is more powerful but more expensive,
and should be done incrementally.

The use of closures here is perhaps a bit unusual,
but during development it proved critical to having readable code.
We must decide early on whether we can safely do the CFG modifications,
and then later fix up the phis if so.
Safely storing state and decisions across these two phases is hard to do readably.
Closures solve the problem neatly.

I manually instrumented the code paths in shortcircuitPhiPlan.
During make.bash there are nearly 6000 invocations.
The least-visited code path gets run 85 times,
so all the code in this CL is reasonably well-exercised.

Here is a concrete example of code improved by this change:

func f(e interface{}) int {
	if x, ok := e.(int); ok {
		return x
	}
	return 0
}

Omitting PCDATA, FUNCDATA, and the like, it used to compile to:

"".f STEXT nosplit size=50 args=0x18 locals=0x0
	0x0000 00000 (x.go:4)	LEAQ	type.int(SB), AX
	0x0007 00007 (x.go:4)	MOVQ	"".e+8(SP), CX
	0x000c 00012 (x.go:4)	CMPQ	AX, CX
	0x000f 00015 (x.go:4)	JNE	43
	0x0011 00017 (x.go:4)	MOVQ	"".e+16(SP), AX
	0x0016 00022 (x.go:4)	MOVQ	(AX), AX
	0x0019 00025 (x.go:4)	JNE	33
	0x001b 00027 (x.go:5)	MOVQ	AX, "".~r1+24(SP)
	0x0020 00032 (x.go:5)	RET
	0x0021 00033 (x.go:7)	MOVQ	$0, "".~r1+24(SP)
	0x002a 00042 (x.go:7)	RET
	0x002b 00043 (x.go:7)	MOVL	$0, AX
	0x0030 00048 (x.go:4)	JMP	25

Afterwards, it compiles to:

"".f STEXT nosplit size=41 args=0x18 locals=0x0
	0x0000 00000 (x.go:4)	LEAQ	type.int(SB), AX
	0x0007 00007 (x.go:4)	MOVQ	"".e+8(SP), CX
	0x000c 00012 (x.go:4)	CMPQ	AX, CX
	0x000f 00015 (x.go:4)	JNE	31
	0x0011 00017 (x.go:4)	MOVQ	"".e+16(SP), AX
	0x0016 00022 (x.go:4)	MOVQ	(AX), AX
	0x0019 00025 (x.go:5)	MOVQ	AX, "".~r1+24(SP)
	0x001e 00030 (x.go:5)	RET
	0x001f 00031 (x.go:7)	MOVQ	$0, "".~r1+24(SP)
	0x0028 00040 (x.go:7)	RET

Note that there is now only a single JNE and a single RET $0 path.

Updates #37608

Has a minor good effect on compilation speed and memory use.

Provides widespread improvements to generated code.
The rare, minor regressions I have investigated are due to
register allocation fluctuations.

file      before    after     Δ       %       
addr2line 4376080   4371984   -4096   -0.094% 
api       5945400   5933112   -12288  -0.207% 
asm       5034312   5030216   -4096   -0.081% 
buildid   2844952   2840856   -4096   -0.144% 
cgo       4812872   4804680   -8192   -0.170% 
compile   19622064  19610368  -11696  -0.060% 
cover     5236648   5232552   -4096   -0.078% 
dist      3658312   3654216   -4096   -0.112% 
doc       4653512   4649416   -4096   -0.088% 
fix       3370072   3365976   -4096   -0.122% 
link      6671864   6667768   -4096   -0.061% 
pprof     14781652  14761172  -20480  -0.139% 
trace     11639684  11627396  -12288  -0.106% 
vet       8252280   8231800   -20480  -0.248% 
total     115052984 114934792 -118192 -0.103% 


file                                                                     before   after    Δ       %       
internal/cpu.s                                                           3298     3296     -2      -0.061% 
internal/bytealg.s                                                       1730     1737     +7      +0.405% 
cmd/vendor/golang.org/x/mod/semver.s                                     7332     7283     -49     -0.668% 
image/color.s                                                            8248     8156     -92     -1.115% 
math.s                                                                   35966    35956    -10     -0.028% 
math/cmplx.s                                                             6596     6575     -21     -0.318% 
runtime.s                                                                480566   480053   -513    -0.107% 
sync.s                                                                   16408    16385    -23     -0.140% 
math/rand.s                                                              10447    10406    -41     -0.392% 
internal/reflectlite.s                                                   28408    28366    -42     -0.148% 
errors.s                                                                 2736     2701     -35     -1.279% 
sort.s                                                                   17031    17036    +5      +0.029% 
io.s                                                                     16993    16964    -29     -0.171% 
container/heap.s                                                         2006     1997     -9      -0.449% 
text/tabwriter.s                                                         9570     9552     -18     -0.188% 
bytes.s                                                                  31823    31594    -229    -0.720% 
strconv.s                                                                52760    52717    -43     -0.082% 
vendor/golang.org/x/text/transform.s                                     16713    16706    -7      -0.042% 
strings.s                                                                42590    42563    -27     -0.063% 
bufio.s                                                                  22883    22785    -98     -0.428% 
encoding/base32.s                                                        9586     9531     -55     -0.574% 
syscall.s                                                                82237    82243    +6      +0.007% 
image.s                                                                  37465    37452    -13     -0.035% 
regexp/syntax.s                                                          82827    82769    -58     -0.070% 
image/draw.s                                                             18698    18584    -114    -0.610% 
image/jpeg.s                                                             36560    36549    -11     -0.030% 
time.s                                                                   82557    82526    -31     -0.038% 
context.s                                                                10863    10820    -43     -0.396% 
regexp.s                                                                 64114    64049    -65     -0.101% 
os.s                                                                     51751    51524    -227    -0.439% 
reflect.s                                                                168240   168049   -191    -0.114% 
cmd/go/internal/lockedfile/internal/filelock.s                           2317     2290     -27     -1.165% 
path/filepath.s                                                          17831    17766    -65     -0.365% 
io/ioutil.s                                                              6994     6990     -4      -0.057% 
encoding/binary.s                                                        30791    30726    -65     -0.211% 
cmd/vendor/golang.org/x/sys/unix.s                                       78055    78033    -22     -0.028% 
encoding/pem.s                                                           9280     9247     -33     -0.356% 
crypto/cipher.s                                                          20376    20374    -2      -0.010% 
os/exec.s                                                                29229    29140    -89     -0.304% 
internal/goroot.s                                                        4588     4579     -9      -0.196% 
cmd/internal/browser.s                                                   2246     2240     -6      -0.267% 
cmd/vendor/golang.org/x/crypto/ssh/terminal.s                            27183    27149    -34     -0.125% 
fmt.s                                                                    76625    76484    -141    -0.184% 
encoding/hex.s                                                           6154     6152     -2      -0.032% 
compress/lzw.s                                                           7063     7059     -4      -0.057% 
database/sql/driver.s                                                    18875    18862    -13     -0.069% 
debug/plan9obj.s                                                         8268     8266     -2      -0.024% 
net/url.s                                                                29724    29719    -5      -0.017% 
encoding/csv.s                                                           12872    12856    -16     -0.124% 
debug/gosym.s                                                            25303    25268    -35     -0.138% 
compress/flate.s                                                         50952    51019    +67     +0.131% 
compress/zlib.s                                                          7277     7266     -11     -0.151% 
archive/zip.s                                                            42155    42111    -44     -0.104% 
debug/dwarf.s                                                            107632   107541   -91     -0.085% 
database/sql.s                                                           98373    98028    -345    -0.351% 
os/user.s                                                                14722    14708    -14     -0.095% 
encoding/json.s                                                          105836   105711   -125    -0.118% 
debug/macho.s                                                            32598    32560    -38     -0.117% 
encoding/gob.s                                                           136478   135755   -723    -0.530% 
debug/pe.s                                                               31160    30869    -291    -0.934% 
debug/elf.s                                                              63495    63302    -193    -0.304% 
vendor/golang.org/x/text/unicode/bidi.s                                  27220    27217    -3      -0.011% 
vendor/golang.org/x/text/secure/bidirule.s                               3363     3352     -11     -0.327% 
go/token.s                                                               12036    12035    -1      -0.008% 
flag.s                                                                   22277    22256    -21     -0.094% 
mime.s                                                                   39696    39509    -187    -0.471% 
go/scanner.s                                                             19033    19020    -13     -0.068% 
archive/tar.s                                                            70936    70581    -355    -0.500% 
internal/xcoff.s                                                         22823    22820    -3      -0.013% 
text/scanner.s                                                           11631    11629    -2      -0.017% 
encoding/xml.s                                                           110534   110408   -126    -0.114% 
math/big.s                                                               183636   183545   -91     -0.050% 
image/gif.s                                                              27376    27343    -33     -0.121% 
crypto/dsa.s                                                             6029     5969     -60     -0.995% 
image/png.s                                                              42947    42939    -8      -0.019% 
crypto/rand.s                                                            6866     6854     -12     -0.175% 
vendor/golang.org/x/text/unicode/norm.s                                  66394    66354    -40     -0.060% 
runtime/trace.s                                                          2603     2521     -82     -3.150% 
crypto/ed25519.s                                                         6321     6300     -21     -0.332% 
text/template/parse.s                                                    93910    93844    -66     -0.070% 
crypto/rsa.s                                                             31460    31369    -91     -0.289% 
encoding/asn1.s                                                          57021    57023    +2      +0.004% 
crypto/elliptic.s                                                        51382    51363    -19     -0.037% 
crypto/x509/pkix.s                                                       10386    10342    -44     -0.424% 
vendor/golang.org/x/net/idna.s                                           24482    24466    -16     -0.065% 
vendor/golang.org/x/crypto/cryptobyte.s                                  33479    33280    -199    -0.594% 
crypto/ecdsa.s                                                           11936    11883    -53     -0.444% 
go/constant.s                                                            43670    42663    -1007   -2.306% 
go/ast.s                                                                 80383    80191    -192    -0.239% 
testing.s                                                                68069    68057    -12     -0.018% 
runtime/pprof.s                                                          59613    59603    -10     -0.017% 
testing/iotest.s                                                         4895     4891     -4      -0.082% 
internal/trace.s                                                         78136    78089    -47     -0.060% 
cmd/internal/goobj2.s                                                    13158    13154    -4      -0.030% 
cmd/internal/src.s                                                       17661    17657    -4      -0.023% 
go/parser.s                                                              79046    78880    -166    -0.210% 
cmd/internal/objabi.s                                                    16367    16343    -24     -0.147% 
text/template.s                                                          94899    94486    -413    -0.435% 
go/printer.s                                                             77267    76992    -275    -0.356% 
cmd/internal/goobj.s                                                     25988    25947    -41     -0.158% 
runtime/pprof/internal/profile.s                                         102066   101933   -133    -0.130% 
go/format.s                                                              5419     5371     -48     -0.886% 
cmd/vendor/golang.org/x/arch/ppc64/ppc64asm.s                            37181    37149    -32     -0.086% 
go/doc.s                                                                 74533    74132    -401    -0.538% 
html/template.s                                                          88743    88389    -354    -0.399% 
cmd/asm/internal/lex.s                                                   24881    24872    -9      -0.036% 
cmd/internal/buildid.s                                                   18263    18256    -7      -0.038% 
cmd/vendor/golang.org/x/arch/x86/x86asm.s                                80036    79980    -56     -0.070% 
go/build.s                                                               68905    68737    -168    -0.244% 
cmd/cover.s                                                              46070    45950    -120    -0.260% 
cmd/internal/obj.s                                                       117001   116991   -10     -0.009% 
cmd/doc.s                                                                62700    62419    -281    -0.448% 
cmd/internal/obj/arm.s                                                   66745    66687    -58     -0.087% 
cmd/compile/internal/syntax.s                                            145406   145062   -344    -0.237% 
cmd/internal/obj/wasm.s                                                  44049    44027    -22     -0.050% 
net.s                                                                    291835   291020   -815    -0.279% 
cmd/dist.s                                                               209020   208807   -213    -0.102% 
cmd/cgo.s                                                                241564   241102   -462    -0.191% 
vendor/golang.org/x/net/http/httpproxy.s                                 9407     9399     -8      -0.085% 
log/syslog.s                                                             7921     7909     -12     -0.151% 
go/types.s                                                               319325   317513   -1812   -0.567% 
vendor/golang.org/x/net/http/httpguts.s                                  3834     3825     -9      -0.235% 
mime/multipart.s                                                         21414    21343    -71     -0.332% 
cmd/internal/obj/ppc64.s                                                 119949   119938   -11     -0.009% 
cmd/compile/internal/logopt.s                                            10158    10118    -40     -0.394% 
vendor/golang.org/x/net/nettest.s                                        28012    27991    -21     -0.075% 
go/internal/srcimporter.s                                                6405     6380     -25     -0.390% 
go/internal/gcimporter.s                                                 34525    34493    -32     -0.093% 
net/mail.s                                                               23937    23720    -217    -0.907% 
go/internal/gccgoimporter.s                                              56095    56038    -57     -0.102% 
cmd/compile/internal/types.s                                             47247    47207    -40     -0.085% 
cmd/api.s                                                                39582    39558    -24     -0.061% 
cmd/go/internal/base.s                                                   12572    12551    -21     -0.167% 
cmd/vendor/golang.org/x/xerrors.s                                        17846    17814    -32     -0.179% 
cmd/vendor/golang.org/x/mod/sumdb/note.s                                 18142    18070    -72     -0.397% 
cmd/go/internal/search.s                                                 19994    19876    -118    -0.590% 
cmd/go/internal/imports.s                                                16457    16428    -29     -0.176% 
cmd/vendor/golang.org/x/mod/module.s                                     17838    17759    -79     -0.443% 
cmd/go/internal/cache.s                                                  30551    30514    -37     -0.121% 
cmd/vendor/golang.org/x/mod/sumdb/tlog.s                                 36356    36321    -35     -0.096% 
cmd/internal/test2json.s                                                 9452     9408     -44     -0.466% 
cmd/go/internal/mvs.s                                                    25136    25092    -44     -0.175% 
cmd/go/internal/txtar.s                                                  3488     3461     -27     -0.774% 
cmd/vendor/golang.org/x/mod/zip.s                                        18811    18800    -11     -0.058% 
cmd/go/internal/version.s                                                11213    11171    -42     -0.375% 
cmd/link/internal/benchmark.s                                            4941     4949     +8      +0.162% 
cmd/internal/obj/s390x.s                                                 126865   126849   -16     -0.013% 
cmd/gofmt.s                                                              30684    30596    -88     -0.287% 
cmd/fix.s                                                                87450    86906    -544    -0.622% 
cmd/internal/obj/x86.s                                                   88578    88556    -22     -0.025% 
cmd/vendor/golang.org/x/mod/modfile.s                                    72450    72363    -87     -0.120% 
cmd/oldlink/internal/loader.s                                            16743    16741    -2      -0.012% 
cmd/pack.s                                                               14863    14861    -2      -0.013% 
cmd/go/internal/load.s                                                   106742   106568   -174    -0.163% 
cmd/oldlink/internal/objfile.s                                           21787    21780    -7      -0.032% 
cmd/oldlink/internal/loadmacho.s                                         29309    29317    +8      +0.027% 
cmd/oldlink/internal/loadelf.s                                           35013    35021    +8      +0.023% 
cmd/asm/internal/asm.s                                                   68550    68538    -12     -0.018% 
cmd/link/internal/loader.s                                               94765    94564    -201    -0.212% 
cmd/link/internal/loadelf.s                                              35663    35667    +4      +0.011% 
cmd/link/internal/loadmacho.s                                            29501    29509    +8      +0.027% 
cmd/vendor/golang.org/x/tools/go/analysis.s                              4983     4976     -7      -0.140% 
cmd/vendor/golang.org/x/tools/go/analysis/internal/analysisflags.s       16771    16709    -62     -0.370% 
cmd/vendor/golang.org/x/tools/go/types/objectpath.s                      18481    18456    -25     -0.135% 
cmd/vendor/golang.org/x/tools/go/analysis/passes/internal/analysisutil.s 2100     2085     -15     -0.714% 
cmd/vendor/github.com/google/pprof/profile.s                             150141   149620   -521    -0.347% 
cmd/vendor/github.com/google/pprof/internal/measurement.s                10420    10404    -16     -0.154% 
cmd/vendor/golang.org/x/tools/go/analysis/passes/asmdecl.s               36814    36755    -59     -0.160% 
cmd/vendor/golang.org/x/tools/go/analysis/passes/bools.s                 6688     6673     -15     -0.224% 
cmd/vendor/golang.org/x/tools/go/analysis/passes/cgocall.s               9856     9784     -72     -0.731% 
cmd/vendor/golang.org/x/tools/go/analysis/passes/composite.s             3011     2979     -32     -1.063% 
cmd/vendor/golang.org/x/tools/go/analysis/passes/copylock.s              9737     9682     -55     -0.565% 
cmd/vendor/golang.org/x/tools/go/cfg.s                                   30738    30725    -13     -0.042% 
cmd/vendor/github.com/ianlancetaylor/demangle.s                          175195   174513   -682    -0.389% 
cmd/vendor/golang.org/x/tools/go/analysis/passes/httpresponse.s          3625     3520     -105    -2.897% 
cmd/vendor/golang.org/x/tools/go/analysis/passes/loopclosure.s           2987     2971     -16     -0.536% 
cmd/vendor/golang.org/x/tools/go/analysis/passes/shift.s                 4372     4340     -32     -0.732% 
cmd/vendor/golang.org/x/tools/go/analysis/passes/stdmethods.s            8634     8611     -23     -0.266% 
cmd/vendor/golang.org/x/tools/go/analysis/passes/tests.s                 6189     6164     -25     -0.404% 
cmd/vendor/golang.org/x/tools/go/analysis/passes/structtag.s             8089     8073     -16     -0.198% 
cmd/vendor/golang.org/x/tools/go/analysis/passes/unsafeptr.s             2208     2177     -31     -1.404% 
cmd/vendor/golang.org/x/tools/go/analysis/passes/unreachable.s           8050     8047     -3      -0.037% 
cmd/vendor/golang.org/x/tools/go/analysis/passes/unusedresult.s          3665     3629     -36     -0.982% 
cmd/vendor/golang.org/x/tools/go/ast/astutil.s                           65773    65680    -93     -0.141% 
cmd/vendor/golang.org/x/tools/go/analysis/unitchecker.s                  13328    13286    -42     -0.315% 
cmd/vendor/golang.org/x/tools/go/types/typeutil.s                        12263    12162    -101    -0.824% 
cmd/vendor/golang.org/x/tools/go/analysis/passes/errorsas.s              1459     1421     -38     -2.605% 
cmd/vendor/golang.org/x/tools/go/analysis/passes/ctrlflow.s              5208     5191     -17     -0.326% 
cmd/vendor/golang.org/x/tools/go/analysis/passes/unmarshal.s             1801     1782     -19     -1.055% 
cmd/vendor/golang.org/x/tools/go/analysis/passes/lostcancel.s            9569     9528     -41     -0.428% 
cmd/go/internal/work.s                                                   304928   304756   -172    -0.056% 
crypto/x509.s                                                            147340   147139   -201    -0.136% 
cmd/vendor/golang.org/x/tools/go/analysis/passes/printf.s                34287    34019    -268    -0.782% 
crypto/tls.s                                                             311603   310644   -959    -0.308% 
cmd/oldlink/internal/ld.s                                                533115   532651   -464    -0.087% 
cmd/oldlink/internal/wasm.s                                              16484    16458    -26     -0.158% 
cmd/oldlink/internal/x86.s                                               18832    18830    -2      -0.011% 
cmd/link/internal/ld.s                                                   548200   547626   -574    -0.105% 
cmd/link/internal/wasm.s                                                 16760    16734    -26     -0.155% 
cmd/link/internal/arm64.s                                                20850    20840    -10     -0.048% 
cmd/link/internal/x86.s                                                  17437    17435    -2      -0.011% 
net/http.s                                                               556647   555519   -1128   -0.203% 
net/http/cookiejar.s                                                     15849    15833    -16     -0.101% 
expvar.s                                                                 9521     9508     -13     -0.137% 
net/http/httptest.s                                                      16471    16452    -19     -0.115% 
cmd/vendor/github.com/google/pprof/internal/plugin.s                     4266     4264     -2      -0.047% 
net/http/cgi.s                                                           23448    23428    -20     -0.085% 
cmd/go/internal/web.s                                                    16472    16428    -44     -0.267% 
net/http/httputil.s                                                      39672    39670    -2      -0.005% 
net/rpc.s                                                                33989    33965    -24     -0.071% 
net/http/fcgi.s                                                          19167    19162    -5      -0.026% 
cmd/vendor/github.com/google/pprof/internal/symbolz.s                    5861     5857     -4      -0.068% 
cmd/vendor/github.com/google/pprof/internal/binutils.s                   35842    35823    -19     -0.053% 
cmd/vendor/github.com/google/pprof/internal/symbolizer.s                 11449    11404    -45     -0.393% 
cmd/go/internal/get.s                                                    62726    62582    -144    -0.230% 
cmd/vendor/github.com/google/pprof/internal/report.s                     80032    80022    -10     -0.012% 
cmd/go/internal/modfetch/codehost.s                                      89005    88871    -134    -0.151% 
cmd/trace.s                                                              116607   116496   -111    -0.095% 
cmd/vendor/github.com/google/pprof/internal/driver.s                     143234   143207   -27     -0.019% 
cmd/vendor/github.com/google/pprof/driver.s                              9000     8998     -2      -0.022% 
cmd/go/internal/modfetch.s                                               126300   125726   -574    -0.454% 
cmd/pprof.s                                                              12317    12312    -5      -0.041% 
cmd/go/internal/modconv.s                                                17878    17861    -17     -0.095% 
cmd/go/internal/modload.s                                                150261   149763   -498    -0.331% 
cmd/go/internal/clean.s                                                  11122    11091    -31     -0.279% 
cmd/go/internal/help.s                                                   6523     6521     -2      -0.031% 
cmd/go/internal/generate.s                                               11627    11614    -13     -0.112% 
cmd/go/internal/envcmd.s                                                 22034    21986    -48     -0.218% 
cmd/go/internal/modget.s                                                 38478    38398    -80     -0.208% 
cmd/go/internal/modcmd.s                                                 46430    46229    -201    -0.433% 
cmd/go/internal/test.s                                                   64399    64374    -25     -0.039% 
cmd/compile/internal/ssa.s                                               3615264  3608276  -6988   -0.193% 
cmd/compile/internal/gc.s                                                1538865  1537625  -1240   -0.081% 
cmd/compile/internal/amd64.s                                             33593    33574    -19     -0.057% 
cmd/compile/internal/x86.s                                               30871    30852    -19     -0.062% 
total                                                                    19343565 19311284 -32281  -0.167% 

Change-Id: Ib030eb79458827a5a5b6d0d2f98765f8325a4d7e
Reviewed-on: https://go-review.googlesource.com/c/go/+/222923
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
 2020-04-08 22:13:38 +00:00
Ruixin(Peter) Bao
b2790a2838 cmd/compile: allow floating point Ops to produce flags on s390x 
On s390x, some floating point arithmetic instructions (FSUB, FADD)  generate flag.
This patch allows those related SSA ops to return a tuple, where the second argument of
the tuple is the generated flag. We can use the flag and remove the
subsequent comparison instruction (e.g: LTDBR).

This CL also reduces the .text section for math.test binary by 0.4KB.

Benchmarks:
name                    old time/op  new time/op  delta
Acos-18                 12.1ns ± 0%  12.1ns ± 0%     ~     (all equal)
Acosh-18                18.5ns ± 0%  18.5ns ± 0%     ~     (all equal)
Asin-18                 13.1ns ± 0%  13.1ns ± 0%     ~     (all equal)
Asinh-18                19.4ns ± 0%  19.5ns ± 1%     ~     (p=0.444 n=5+5)
Atan-18                 10.0ns ± 0%  10.0ns ± 0%     ~     (all equal)
Atanh-18                19.1ns ± 1%  19.2ns ± 2%     ~     (p=0.841 n=5+5)
Atan2-18                16.4ns ± 0%  16.4ns ± 0%     ~     (all equal)
Cbrt-18                 14.8ns ± 0%  14.8ns ± 0%     ~     (all equal)
Ceil-18                 0.78ns ± 0%  0.78ns ± 0%     ~     (all equal)
Copysign-18             0.80ns ± 0%  0.80ns ± 0%     ~     (all equal)
Cos-18                  7.19ns ± 0%  7.19ns ± 0%     ~     (p=0.556 n=4+5)
Cosh-18                 12.4ns ± 0%  12.4ns ± 0%     ~     (all equal)
Erf-18                  10.8ns ± 0%  10.8ns ± 0%     ~     (all equal)
Erfc-18                 11.0ns ± 0%  11.0ns ± 0%     ~     (all equal)
Erfinv-18               23.0ns ±16%  26.8ns ± 1%  +16.90%  (p=0.008 n=5+5)
Erfcinv-18              23.3ns ±15%  26.1ns ± 7%     ~     (p=0.087 n=5+5)
Exp-18                  8.67ns ± 0%  8.67ns ± 0%     ~     (p=1.000 n=4+4)
ExpGo-18                50.8ns ± 3%  52.4ns ± 2%     ~     (p=0.063 n=5+5)
Expm1-18                9.49ns ± 1%  9.47ns ± 0%     ~     (p=1.000 n=5+5)
Exp2-18                 52.7ns ± 1%  50.5ns ± 3%   -4.10%  (p=0.024 n=5+5)
Exp2Go-18               50.6ns ± 1%  48.4ns ± 3%   -4.39%  (p=0.008 n=5+5)
Abs-18                  0.67ns ± 0%  0.67ns ± 0%     ~     (p=0.444 n=5+5)
Dim-18                  1.02ns ± 0%  1.03ns ± 0%   +0.98%  (p=0.008 n=5+5)
Floor-18                0.78ns ± 0%  0.78ns ± 0%     ~     (all equal)
Max-18                  3.09ns ± 1%  3.05ns ± 0%   -1.42%  (p=0.008 n=5+5)
Min-18                  3.32ns ± 1%  3.30ns ± 0%   -0.72%  (p=0.016 n=5+4)
Mod-18                  62.3ns ± 1%  65.8ns ± 3%   +5.55%  (p=0.008 n=5+5)
Frexp-18                5.05ns ± 2%  4.98ns ± 0%     ~     (p=0.683 n=5+5)
Gamma-18                24.4ns ± 0%  24.1ns ± 0%   -1.23%  (p=0.008 n=5+5)
Hypot-18                10.3ns ± 0%  10.3ns ± 0%     ~     (all equal)
HypotGo-18              10.2ns ± 0%  10.2ns ± 0%     ~     (all equal)
Ilogb-18                3.56ns ± 1%  3.54ns ± 0%     ~     (p=0.595 n=5+5)
J0-18                    113ns ± 0%   108ns ± 1%   -4.42%  (p=0.016 n=4+5)
J1-18                    115ns ± 0%   109ns ± 1%   -4.87%  (p=0.016 n=4+5)
Jn-18                    240ns ± 0%   230ns ± 2%   -4.41%  (p=0.008 n=5+5)
Ldexp-18                6.19ns ± 0%  6.19ns ± 0%     ~     (p=0.444 n=5+5)
Lgamma-18               32.2ns ± 0%  32.2ns ± 0%     ~     (all equal)
Log-18                  13.1ns ± 0%  13.1ns ± 0%     ~     (all equal)
Logb-18                 4.23ns ± 0%  4.22ns ± 0%     ~     (p=0.444 n=5+5)
Log1p-18                12.7ns ± 0%  12.7ns ± 0%     ~     (all equal)
Log10-18                18.1ns ± 0%  18.2ns ± 0%     ~     (p=0.167 n=5+5)
Log2-18                 14.0ns ± 0%  14.0ns ± 0%     ~     (all equal)
Modf-18                 10.4ns ± 0%  10.5ns ± 0%   +0.96%  (p=0.016 n=4+5)
Nextafter32-18          11.3ns ± 0%  11.3ns ± 0%     ~     (all equal)
Nextafter64-18          4.01ns ± 1%  3.97ns ± 0%     ~     (p=0.333 n=5+4)
PowInt-18               32.7ns ± 0%  32.7ns ± 0%     ~     (all equal)
PowFrac-18              33.2ns ± 0%  33.1ns ± 0%     ~     (p=0.095 n=4+5)
Pow10Pos-18             1.58ns ± 0%  1.58ns ± 0%     ~     (all equal)
Pow10Neg-18             5.81ns ± 0%  5.81ns ± 0%     ~     (all equal)
Round-18                0.78ns ± 0%  0.78ns ± 0%     ~     (all equal)
RoundToEven-18          0.78ns ± 0%  0.78ns ± 0%     ~     (all equal)
Remainder-18            40.6ns ± 0%  40.7ns ± 0%     ~     (p=0.238 n=5+4)
Signbit-18              1.57ns ± 0%  1.57ns ± 0%     ~     (all equal)
Sin-18                  6.75ns ± 0%  6.74ns ± 0%     ~     (p=0.333 n=5+4)
Sincos-18               29.5ns ± 0%  29.5ns ± 0%     ~     (all equal)
Sinh-18                 14.4ns ± 0%  14.4ns ± 0%     ~     (all equal)
SqrtIndirect-18         3.97ns ± 0%  4.15ns ± 0%   +4.59%  (p=0.008 n=5+5)
SqrtLatency-18          8.01ns ± 0%  8.01ns ± 0%     ~     (all equal)
SqrtIndirectLatency-18  11.6ns ± 0%  11.6ns ± 0%     ~     (all equal)
SqrtGoLatency-18        44.7ns ± 0%  45.0ns ± 0%   +0.67%  (p=0.008 n=5+5)
SqrtPrime-18            1.26µs ± 0%  1.27µs ± 0%   +0.63%  (p=0.029 n=4+4)
Tan-18                  11.1ns ± 0%  11.1ns ± 0%     ~     (all equal)
Tanh-18                 15.8ns ± 0%  15.8ns ± 0%     ~     (all equal)
Trunc-18                0.78ns ± 0%  0.78ns ± 0%     ~     (all equal)
Y0-18                    113ns ± 2%   108ns ± 3%   -5.11%  (p=0.008 n=5+5)
Y1-18                    112ns ± 3%   107ns ± 0%   -4.29%  (p=0.000 n=5+4)
Yn-18                    229ns ± 0%   220ns ± 1%   -3.76%  (p=0.016 n=4+5)
Float64bits-18          1.09ns ± 0%  1.09ns ± 0%     ~     (all equal)
Float64frombits-18      0.55ns ± 0%  0.55ns ± 0%     ~     (all equal)
Float32bits-18          0.96ns ±16%  0.86ns ± 0%     ~     (p=0.563 n=5+5)
Float32frombits-18      1.03ns ±28%  0.84ns ± 0%     ~     (p=0.167 n=5+5)
FMA-18                  1.60ns ± 0%  1.60ns ± 0%     ~     (all equal)
[Geo mean]              10.0ns        9.9ns        -0.41%
Change-Id: Ief7e63ea5a8ba404b0a4696e12b9b7e0b05a9a03
Reviewed-on: https://go-review.googlesource.com/c/go/+/209160
Reviewed-by: Michael Munday <mike.munday@ibm.com>
Run-TryBot: Michael Munday <mike.munday@ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
 2020-04-08 20:57:58 +00:00
Michael Munday
bfd569fcb0 cmd/compile: delete the floating point Greater and Geq ops 
Extend CL 220417 (which removed the integer Greater and Geq ops) to
floating point comparisons. Greater and Geq can always be
implemented using Less and Leq.

Fixes #37316.

Change-Id: Ieaddb4877dd0ff9037a1dd11d0a9a9e45ced71e7
Reviewed-on: https://go-review.googlesource.com/c/go/+/222397
Run-TryBot: Michael Munday <mike.munday@ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
 2020-04-07 19:55:05 +00:00
Lynn Boger
815509ae31 cmd/compile: improve lowered moves and zeros for ppc64le 
This change includes the following:
- Generate LXV/STXV sequences instead of LXVD2X/STXVD2X on power9.
These instructions do not require an index register, which
allows more loads and stores within a loop without initializing
multiple index registers. The LoweredQuadXXX generate LXV/STXV.
- Create LoweredMoveXXXShort and LoweredZeroXXXShort for short
moves that don't generate loops, and therefore don't clobber the
address registers or flags.
- Use registers other than R3 and R4 to avoid conflicting with
registers that have already been allocated to avoid unnecessary
register moves.
- Eliminate the use of R14 as scratch register and use R31
instead.
- Add PCALIGN when the LoweredMoveXXX or LoweredZeroXXX generates a
loop with more than 3 iterations.

This performance opportunity was noticed in github.com/golang/snappy
benchmarks. Results on power9:

WordsDecode1e1    54.1ns ± 0%    53.8ns ± 0%   -0.51%  (p=0.029 n=4+4)
WordsDecode1e2     287ns ± 0%     282ns ± 1%   -1.83%  (p=0.029 n=4+4)
WordsDecode1e3    3.98µs ± 0%    3.64µs ± 0%   -8.52%  (p=0.029 n=4+4)
WordsDecode1e4    66.9µs ± 0%    67.0µs ± 0%   +0.20%  (p=0.029 n=4+4)
WordsDecode1e5     723µs ± 0%     723µs ± 0%   -0.01%  (p=0.200 n=4+4)
WordsDecode1e6    7.21ms ± 0%    7.21ms ± 0%   -0.02%  (p=1.000 n=4+4)
WordsEncode1e1    29.9ns ± 0%    29.4ns ± 0%   -1.51%  (p=0.029 n=4+4)
WordsEncode1e2    2.12µs ± 0%    1.75µs ± 0%  -17.70%  (p=0.029 n=4+4)
WordsEncode1e3    11.7µs ± 0%    11.2µs ± 0%   -4.61%  (p=0.029 n=4+4)
WordsEncode1e4     119µs ± 0%     120µs ± 0%   +0.36%  (p=0.029 n=4+4)
WordsEncode1e5    1.21ms ± 0%    1.22ms ± 0%   +0.41%  (p=0.029 n=4+4)
WordsEncode1e6    12.0ms ± 0%    12.0ms ± 0%   +0.57%  (p=0.029 n=4+4)
RandomEncode       286µs ± 0%     203µs ± 0%  -28.82%  (p=0.029 n=4+4)
ExtendMatch       47.4µs ± 0%    47.0µs ± 0%   -0.85%  (p=0.029 n=4+4)

Change-Id: Iecad3a39ae55280286e42760a5c9d5c1168f5858
Reviewed-on: https://go-review.googlesource.com/c/go/+/226539
Run-TryBot: Lynn Boger <laboger@linux.vnet.ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
 2020-04-06 12:09:39 +00:00
Josh Bleecher Snyder
fff7509d47 cmd/compile: add intrinsic HasCPUFeature for checking cpu features 
Before using some CPU instructions, we must check for their presence.
We use global variables in the runtime package to record features.

Prior to this CL, we issued a regular memory load for these features.
The downside to this is that, because it is a regular memory load,
it cannot be hoisted out of loops or otherwise reordered with other loads.

This CL introduces a new intrinsic just for checking cpu features.
It still ends up resulting in a memory load, but that memory load can
now be floated to the entry block and rematerialized as needed.

One downside is that the regular load could be combined with the comparison
into a CMPBconstload+NE. This new intrinsic cannot; it generates MOVB+TESTB+NE.
(It is possible that MOVBQZX+TESTQ+NE would be better.)

This CL does only amd64. It is easy to extend to other architectures.

For the benchmark in #36196, on my machine, this offers a mild speedup.

name      old time/op  new time/op  delta
FMA-8     1.39ns ± 6%  1.29ns ± 9%  -7.19%  (p=0.000 n=97+96)
NonFMA-8  2.03ns ±11%  2.04ns ±12%    ~     (p=0.618 n=99+98)

Updates #15808
Updates #36196

Change-Id: I75e2fcfcf5a6df1bdb80657a7143bed69fca6deb
Reviewed-on: https://go-review.googlesource.com/c/go/+/212360
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Giovanni Bajo <rasky@develer.com>
 2020-04-04 01:01:04 +00:00
Keith Randall
bba88467f8 cmd/compile: add indexed-load CMP instructions 
Things like CMPQ 4(AX)(BX*8), CX

Fixes #37955

Change-Id: Icbed430f65c91a0e3f38a633d8321d79433ad8b3
Reviewed-on: https://go-review.googlesource.com/c/go/+/224219
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
 2020-04-01 17:03:26 +00:00
Josh Bleecher Snyder
8114242359 cmd/compile, runtime: use more registers for amd64 write barrier calls 
The compiler-inserted write barrier calls use a special ABI
for speed and to minimize the binary size impact.

runtime.gcWriteBarrier takes its args in DI and AX.
This change adds gcWriteBarrier wrapper functions,
varying only in the register used for the second argument.
(Allowing variation in the first argument doesn't offer improvements,
which is convenient, as it avoids quadratic API growth.)
This reduces the number of register copies.

The goals are reduced binary size via reduced register pressure/copies.

One downside to this change is that when the write barrier is on,
we may bounce through several different write barrier wrappers,
which is bad for the instruction cache.

Package runtime write barrier benchmarks for this change:

name                old time/op  new time/op  delta
WriteBarrier-8      16.6ns ± 6%  15.6ns ± 6%  -5.73%  (p=0.000 n=97+99)
BulkWriteBarrier-8  4.37ns ± 7%  4.22ns ± 8%  -3.45%  (p=0.000 n=96+99)

However, I don't particularly trust these numbers.
I ran runtime.BenchmarkWriteBarrier multiple times as I rebased
this change, and noticed that the results have high variance
depending on the parent change, perhaps due to aligment.

This change was stress tested with GOGC=1 GODEBUG=gccheckmark=1 go test std.

This change reduces binary sizes:

file      before    after     Δ       %
addr2line 4308720   4296688   -12032  -0.279%
api       5965592   5945368   -20224  -0.339%
asm       5148088   5025464   -122624 -2.382%
buildid   2848760   2844904   -3856   -0.135%
cgo       4828968   4812840   -16128  -0.334%
compile   19754720  19529744  -224976 -1.139%
cover     5256840   5236600   -20240  -0.385%
dist      3670312   3658264   -12048  -0.328%
doc       4669608   4657576   -12032  -0.258%
fix       3377976   3365944   -12032  -0.356%
link      6614888   6586472   -28416  -0.430%
nm        4258368   4254528   -3840   -0.090%
objdump   4656336   4644304   -12032  -0.258%
pack      2295176   2295432   +256    +0.011%
pprof     14762356  14709364  -52992  -0.359%
test2json 2824456   2820600   -3856   -0.137%
trace     11684404  11643700  -40704  -0.348%
vet       8284760   8252248   -32512  -0.392%
total     115210328 114580040 -630288 -0.547%

This change improves compiler performance:

name        old time/op       new time/op       delta
Template          208ms ± 3%        207ms ± 3%  -0.40%  (p=0.030 n=43+44)
Unicode          80.2ms ± 3%       81.3ms ± 3%  +1.25%  (p=0.000 n=41+44)
GoTypes           699ms ± 3%        694ms ± 2%  -0.71%  (p=0.016 n=42+37)
Compiler          3.26s ± 2%        3.23s ± 2%  -0.86%  (p=0.000 n=43+45)
SSA               6.97s ± 1%        6.93s ± 1%  -0.63%  (p=0.000 n=43+45)
Flate             134ms ± 3%        133ms ± 2%    ~     (p=0.139 n=45+42)
GoParser          165ms ± 2%        164ms ± 1%  -0.79%  (p=0.000 n=45+40)
Reflect           434ms ± 4%        435ms ± 4%    ~     (p=0.937 n=44+44)
Tar               181ms ± 2%        181ms ± 2%    ~     (p=0.702 n=43+45)
XML               244ms ± 2%        244ms ± 2%    ~     (p=0.237 n=45+44)
[Geo mean]        403ms             402ms       -0.29%

name        old user-time/op  new user-time/op  delta
Template          271ms ± 2%        268ms ± 1%  -1.40%  (p=0.000 n=42+42)
Unicode           117ms ± 3%        116ms ± 5%    ~     (p=0.066 n=45+45)
GoTypes           948ms ± 2%        936ms ± 2%  -1.30%  (p=0.000 n=41+40)
Compiler          4.26s ± 1%        4.21s ± 2%  -1.25%  (p=0.000 n=37+45)
SSA               9.52s ± 2%        9.41s ± 1%  -1.18%  (p=0.000 n=44+45)
Flate             167ms ± 2%        165ms ± 2%  -1.15%  (p=0.000 n=44+41)
GoParser          201ms ± 2%        198ms ± 1%  -1.40%  (p=0.000 n=43+43)
Reflect           563ms ± 8%        560ms ± 7%    ~     (p=0.206 n=45+44)
Tar               224ms ± 2%        222ms ± 2%  -0.81%  (p=0.000 n=45+45)
XML               308ms ± 2%        304ms ± 1%  -1.17%  (p=0.000 n=42+43)
[Geo mean]        525ms             519ms       -1.08%

name        old alloc/op      new alloc/op      delta
Template         36.3MB ± 0%       36.3MB ± 0%    ~     (p=0.421 n=5+5)
Unicode          28.4MB ± 0%       28.3MB ± 0%    ~     (p=0.056 n=5+5)
GoTypes           121MB ± 0%        121MB ± 0%  -0.14%  (p=0.008 n=5+5)
Compiler          567MB ± 0%        567MB ± 0%  -0.06%  (p=0.016 n=4+5)
SSA              1.26GB ± 0%       1.26GB ± 0%  -0.07%  (p=0.008 n=5+5)
Flate            22.9MB ± 0%       22.8MB ± 0%    ~     (p=0.310 n=5+5)
GoParser         28.0MB ± 0%       27.9MB ± 0%  -0.09%  (p=0.008 n=5+5)
Reflect          78.4MB ± 0%       78.4MB ± 0%  -0.03%  (p=0.008 n=5+5)
Tar              34.2MB ± 0%       34.2MB ± 0%  -0.05%  (p=0.008 n=5+5)
XML              44.4MB ± 0%       44.4MB ± 0%  -0.04%  (p=0.016 n=5+5)
[Geo mean]       76.4MB            76.3MB       -0.05%

name        old allocs/op     new allocs/op     delta
Template           356k ± 0%         356k ± 0%  -0.13%  (p=0.008 n=5+5)
Unicode            326k ± 0%         326k ± 0%  -0.07%  (p=0.008 n=5+5)
GoTypes           1.24M ± 0%        1.24M ± 0%  -0.24%  (p=0.008 n=5+5)
Compiler          5.30M ± 0%        5.28M ± 0%  -0.34%  (p=0.008 n=5+5)
SSA               11.9M ± 0%        11.9M ± 0%  -0.16%  (p=0.008 n=5+5)
Flate              226k ± 0%         225k ± 0%  -0.12%  (p=0.008 n=5+5)
GoParser           287k ± 0%         286k ± 0%  -0.29%  (p=0.008 n=5+5)
Reflect            930k ± 0%         929k ± 0%  -0.05%  (p=0.008 n=5+5)
Tar                332k ± 0%         331k ± 0%  -0.12%  (p=0.008 n=5+5)
XML                411k ± 0%         411k ± 0%  -0.12%  (p=0.008 n=5+5)
[Geo mean]         771k              770k       -0.16%

For some packages, this change significantly reduces the size of executable text.
Examples:

file                                   before   after    Δ       %
cmd/internal/obj/arm.s                 68658    66855    -1803   -2.626%
cmd/internal/obj/mips.s                57486    56272    -1214   -2.112%
cmd/internal/obj/arm64.s               152107   147163   -4944   -3.250%
cmd/internal/obj/ppc64.s               125544   120456   -5088   -4.053%
cmd/vendor/golang.org/x/tools/go/cfg.s 31699    30742    -957    -3.019%

Full listing:

file                                                                     before   after    Δ       %
container/ring.s                                                         1890     1870     -20     -1.058%
container/list.s                                                         5366     5390     +24     +0.447%
internal/cpu.s                                                           3298     3295     -3      -0.091%
internal/testlog.s                                                       1507     1501     -6      -0.398%
image/color.s                                                            8281     8248     -33     -0.399%
runtime.s                                                                480970   480075   -895    -0.186%
sync.s                                                                   16497    16408    -89     -0.539%
internal/singleflight.s                                                  2591     2577     -14     -0.540%
math/rand.s                                                              10456    10438    -18     -0.172%
cmd/go/internal/par.s                                                    2801     2790     -11     -0.393%
internal/reflectlite.s                                                   28477    28417    -60     -0.211%
errors.s                                                                 2750     2736     -14     -0.509%
internal/oserror.s                                                       446      434      -12     -2.691%
sort.s                                                                   17061    17046    -15     -0.088%
io.s                                                                     17063    16999    -64     -0.375%
vendor/golang.org/x/crypto/hkdf.s                                        1962     1936     -26     -1.325%
text/tabwriter.s                                                         9617     9574     -43     -0.447%
hash/crc64.s                                                             3414     3408     -6      -0.176%
hash/crc32.s                                                             6657     6651     -6      -0.090%
bytes.s                                                                  31932    31863    -69     -0.216%
strconv.s                                                                53158    52799    -359    -0.675%
strings.s                                                                42829    42665    -164    -0.383%
encoding/ascii85.s                                                       4833     4791     -42     -0.869%
vendor/golang.org/x/text/transform.s                                     16810    16724    -86     -0.512%
path.s                                                                   6848     6845     -3      -0.044%
encoding/base32.s                                                        9658     9592     -66     -0.683%
bufio.s                                                                  23051    22908    -143    -0.620%
compress/bzip2.s                                                         11773    11764    -9      -0.076%
image.s                                                                  37565    37502    -63     -0.168%
syscall.s                                                                82359    82279    -80     -0.097%
regexp/syntax.s                                                          83573    82930    -643    -0.769%
image/jpeg.s                                                             36535    36490    -45     -0.123%
regexp.s                                                                 64396    64214    -182    -0.283%
time.s                                                                   82724    82622    -102    -0.123%
plugin.s                                                                 6539     6536     -3      -0.046%
context.s                                                                10959    10865    -94     -0.858%
internal/poll.s                                                          24286    24270    -16     -0.066%
reflect.s                                                                168304   167927   -377    -0.224%
internal/fmtsort.s                                                       7416     7376     -40     -0.539%
os.s                                                                     52465    51787    -678    -1.292%
cmd/go/internal/lockedfile/internal/filelock.s                           2326     2317     -9      -0.387%
os/signal.s                                                              4657     4648     -9      -0.193%
runtime/debug.s                                                          6040     5998     -42     -0.695%
encoding/binary.s                                                        30838    30801    -37     -0.120%
vendor/golang.org/x/net/route.s                                          23694    23491    -203    -0.857%
path/filepath.s                                                          17895    17889    -6      -0.034%
cmd/vendor/golang.org/x/sys/unix.s                                       78125    78109    -16     -0.020%
io/ioutil.s                                                              6999     6996     -3      -0.043%
encoding/base64.s                                                        12094    12007    -87     -0.719%
crypto/cipher.s                                                          20466    20372    -94     -0.459%
cmd/go/internal/robustio.s                                               2672     2669     -3      -0.112%
encoding/pem.s                                                           9302     9286     -16     -0.172%
internal/obscuretestdata.s                                               1719     1695     -24     -1.396%
crypto/aes.s                                                             11014    11002    -12     -0.109%
os/exec.s                                                                29388    29231    -157    -0.534%
cmd/internal/browser.s                                                   2266     2260     -6      -0.265%
internal/goroot.s                                                        4601     4592     -9      -0.196%
vendor/golang.org/x/crypto/chacha20poly1305.s                            8945     8942     -3      -0.034%
cmd/vendor/golang.org/x/crypto/ssh/terminal.s                            27226    27195    -31     -0.114%
index/suffixarray.s                                                      36431    36411    -20     -0.055%
fmt.s                                                                    77017    76709    -308    -0.400%
encoding/hex.s                                                           6241     6154     -87     -1.394%
compress/lzw.s                                                           7133     7069     -64     -0.897%
database/sql/driver.s                                                    18888    18877    -11     -0.058%
net/url.s                                                                29838    29739    -99     -0.332%
debug/plan9obj.s                                                         8329     8279     -50     -0.600%
encoding/csv.s                                                           12986    12902    -84     -0.647%
debug/gosym.s                                                            25403    25330    -73     -0.287%
compress/flate.s                                                         51192    50970    -222    -0.434%
vendor/golang.org/x/net/dns/dnsmessage.s                                 86769    86208    -561    -0.647%
compress/gzip.s                                                          9791     9758     -33     -0.337%
compress/zlib.s                                                          7310     7277     -33     -0.451%
archive/zip.s                                                            42356    42166    -190    -0.449%
debug/dwarf.s                                                            108259   107730   -529    -0.489%
encoding/json.s                                                          106378   105910   -468    -0.440%
os/user.s                                                                14751    14724    -27     -0.183%
database/sql.s                                                           99011    98404    -607    -0.613%
log.s                                                                    9466     9423     -43     -0.454%
debug/pe.s                                                               31272    31182    -90     -0.288%
debug/macho.s                                                            32764    32608    -156    -0.476%
encoding/gob.s                                                           136976   136517   -459    -0.335%
vendor/golang.org/x/text/unicode/bidi.s                                  27318    27276    -42     -0.154%
archive/tar.s                                                            71416    70975    -441    -0.618%
vendor/golang.org/x/net/http2/hpack.s                                    23892    23848    -44     -0.184%
vendor/golang.org/x/text/secure/bidirule.s                               3354     3351     -3      -0.089%
mime/quotedprintable.s                                                   5960     5925     -35     -0.587%
net/http/internal.s                                                      5874     5853     -21     -0.358%
math/big.s                                                               184147   183692   -455    -0.247%
debug/elf.s                                                              63775    63567    -208    -0.326%
mime.s                                                                   39802    39709    -93     -0.234%
encoding/xml.s                                                           111038   110713   -325    -0.293%
crypto/dsa.s                                                             6044     6029     -15     -0.248%
go/token.s                                                               12139    12077    -62     -0.511%
crypto/rand.s                                                            6889     6866     -23     -0.334%
go/scanner.s                                                             19030    19008    -22     -0.116%
flag.s                                                                   22320    22236    -84     -0.376%
vendor/golang.org/x/text/unicode/norm.s                                  66652    66391    -261    -0.392%
crypto/rsa.s                                                             31671    31650    -21     -0.066%
crypto/elliptic.s                                                        51553    51403    -150    -0.291%
internal/xcoff.s                                                         22950    22822    -128    -0.558%
go/constant.s                                                            43750    43689    -61     -0.139%
encoding/asn1.s                                                          57086    57035    -51     -0.089%
runtime/trace.s                                                          2609     2603     -6      -0.230%
crypto/x509/pkix.s                                                       10458    10471    +13     +0.124%
image/gif.s                                                              27544    27385    -159    -0.577%
vendor/golang.org/x/net/idna.s                                           24558    24502    -56     -0.228%
image/png.s                                                              42775    42685    -90     -0.210%
vendor/golang.org/x/crypto/cryptobyte.s                                  33616    33493    -123    -0.366%
go/ast.s                                                                 80684    80449    -235    -0.291%
net/internal/socktest.s                                                  16571    16535    -36     -0.217%
crypto/ecdsa.s                                                           11948    11936    -12     -0.100%
text/template/parse.s                                                    95138    94002    -1136   -1.194%
runtime/pprof.s                                                          59702    59639    -63     -0.106%
testing.s                                                                68427    68088    -339    -0.495%
internal/testenv.s                                                       5620     5596     -24     -0.427%
testing/internal/testdeps.s                                              3312     3294     -18     -0.543%
internal/trace.s                                                         78473    78239    -234    -0.298%
testing/iotest.s                                                         4968     4908     -60     -1.208%
os/signal/internal/pty.s                                                 3011     2990     -21     -0.697%
testing/quick.s                                                          12179    12125    -54     -0.443%
cmd/internal/bio.s                                                       9286     9274     -12     -0.129%
cmd/internal/src.s                                                       17684    17663    -21     -0.119%
cmd/internal/goobj2.s                                                    12588    12558    -30     -0.238%
cmd/internal/objabi.s                                                    16408    16390    -18     -0.110%
go/printer.s                                                             77417    77308    -109    -0.141%
go/parser.s                                                              80045    79113    -932    -1.164%
go/format.s                                                              5434     5419     -15     -0.276%
cmd/internal/goobj.s                                                     26146    25954    -192    -0.734%
runtime/pprof/internal/profile.s                                         102518   102178   -340    -0.332%
text/template.s                                                          95343    94935    -408    -0.428%
cmd/internal/dwarf.s                                                     31718    31572    -146    -0.460%
cmd/vendor/golang.org/x/arch/arm/armasm.s                                45240    45151    -89     -0.197%
internal/lazytemplate.s                                                  1470     1457     -13     -0.884%
cmd/vendor/golang.org/x/arch/ppc64/ppc64asm.s                            37253    37220    -33     -0.089%
cmd/asm/internal/flags.s                                                 2593     2590     -3      -0.116%
cmd/asm/internal/lex.s                                                   25068    24921    -147    -0.586%
cmd/internal/buildid.s                                                   18536    18263    -273    -1.473%
cmd/vendor/golang.org/x/arch/x86/x86asm.s                                80209    80105    -104    -0.130%
go/doc.s                                                                 75140    74585    -555    -0.739%
cmd/internal/edit.s                                                      3893     3899     +6      +0.154%
html/template.s                                                          89377    88809    -568    -0.636%
cmd/vendor/golang.org/x/arch/arm64/arm64asm.s                            117998   117824   -174    -0.147%
cmd/internal/obj.s                                                       115015   114290   -725    -0.630%
go/build.s                                                               69379    68862    -517    -0.745%
cmd/internal/objfile.s                                                   48106    47982    -124    -0.258%
cmd/cover.s                                                              46239    46113    -126    -0.272%
cmd/addr2line.s                                                          2845     2833     -12     -0.422%
cmd/internal/obj/arm.s                                                   68658    66855    -1803   -2.626%
cmd/internal/obj/mips.s                                                  57486    56272    -1214   -2.112%
cmd/internal/obj/riscv.s                                                 63834    63006    -828    -1.297%
cmd/compile/internal/syntax.s                                            146582   145456   -1126   -0.768%
cmd/internal/obj/wasm.s                                                  44117    44066    -51     -0.116%
cmd/cgo.s                                                                242645   241653   -992    -0.409%
cmd/internal/obj/arm64.s                                                 152107   147163   -4944   -3.250%
net.s                                                                    295972   292010   -3962   -1.339%
go/types.s                                                               321371   319432   -1939   -0.603%
vendor/golang.org/x/net/http/httpproxy.s                                 9450     9423     -27     -0.286%
net/textproto.s                                                          19455    19406    -49     -0.252%
cmd/internal/obj/ppc64.s                                                 125544   120456   -5088   -4.053%
go/internal/srcimporter.s                                                6475     6409     -66     -1.019%
log/syslog.s                                                             8017     7929     -88     -1.098%
cmd/compile/internal/logopt.s                                            10183    10162    -21     -0.206%
net/mail.s                                                               24085    23948    -137    -0.569%
mime/multipart.s                                                         21527    21420    -107    -0.497%
cmd/internal/obj/s390x.s                                                 127610   127757   +147    +0.115%
go/internal/gcimporter.s                                                 34913    34548    -365    -1.045%
vendor/golang.org/x/net/nettest.s                                        28103    28016    -87     -0.310%
cmd/go/internal/cfg.s                                                    9967     9916     -51     -0.512%
cmd/api.s                                                                39703    39603    -100    -0.252%
go/internal/gccgoimporter.s                                              56470    56120    -350    -0.620%
go/importer.s                                                            2077     2056     -21     -1.011%
cmd/compile/internal/types.s                                             48202    47282    -920    -1.909%
cmd/go/internal/str.s                                                    4341     4320     -21     -0.484%
cmd/internal/obj/x86.s                                                   89440    88625    -815    -0.911%
cmd/go/internal/base.s                                                   12667    12580    -87     -0.687%
cmd/go/internal/cache.s                                                  30754    30571    -183    -0.595%
cmd/doc.s                                                                62976    62755    -221    -0.351%
cmd/go/internal/search.s                                                 20114    19993    -121    -0.602%
cmd/vendor/golang.org/x/xerrors.s                                        17923    17855    -68     -0.379%
cmd/go/internal/lockedfile.s                                             16451    16415    -36     -0.219%
cmd/vendor/golang.org/x/mod/sumdb/note.s                                 18200    18150    -50     -0.275%
cmd/vendor/golang.org/x/mod/module.s                                     17869    17851    -18     -0.101%
cmd/asm/internal/arch.s                                                  37533    37482    -51     -0.136%
cmd/fix.s                                                                87728    87492    -236    -0.269%
cmd/vendor/golang.org/x/mod/sumdb/tlog.s                                 36394    36367    -27     -0.074%
cmd/vendor/golang.org/x/mod/sumdb/dirhash.s                              4990     4963     -27     -0.541%
cmd/go/internal/imports.s                                                16499    16469    -30     -0.182%
cmd/vendor/golang.org/x/mod/zip.s                                        18816    18745    -71     -0.377%
cmd/go/internal/cmdflag.s                                                5126     5123     -3      -0.059%
cmd/internal/test2json.s                                                 9540     9452     -88     -0.922%
cmd/go/internal/tool.s                                                   3629     3623     -6      -0.165%
cmd/go/internal/version.s                                                11232    11220    -12     -0.107%
cmd/go/internal/mvs.s                                                    25383    25179    -204    -0.804%
cmd/nm.s                                                                 5815     5803     -12     -0.206%
cmd/dist.s                                                               210146   209140   -1006   -0.479%
cmd/asm/internal/asm.s                                                   68655    68549    -106    -0.154%
cmd/vendor/golang.org/x/mod/modfile.s                                    72974    72510    -464    -0.636%
cmd/go/internal/load.s                                                   107548   106861   -687    -0.639%
cmd/link/internal/sym.s                                                  18708    18581    -127    -0.679%
cmd/asm.s                                                                3367     3343     -24     -0.713%
cmd/gofmt.s                                                              30795    30698    -97     -0.315%
cmd/link/internal/objfile.s                                              21828    21630    -198    -0.907%
cmd/pack.s                                                               14878    14869    -9      -0.060%
cmd/vendor/github.com/google/pprof/internal/elfexec.s                    6788     6782     -6      -0.088%
cmd/test2json.s                                                          1647     1641     -6      -0.364%
cmd/link/internal/loader.s                                               48677    48483    -194    -0.399%
cmd/vendor/golang.org/x/tools/go/analysis/internal/analysisflags.s       16783    16773    -10     -0.060%
cmd/link/internal/loadelf.s                                              35464    35126    -338    -0.953%
cmd/link/internal/loadmacho.s                                            29438    29180    -258    -0.876%
cmd/link/internal/loadpe.s                                               16440    16371    -69     -0.420%
cmd/vendor/golang.org/x/tools/go/analysis/passes/internal/analysisutil.s 2106     2100     -6      -0.285%
cmd/link/internal/loadxcoff.s                                            11711    11615    -96     -0.820%
cmd/vendor/golang.org/x/tools/go/analysis/internal/facts.s               14954    14883    -71     -0.475%
cmd/vendor/golang.org/x/tools/go/ast/inspector.s                         5394     5374     -20     -0.371%
cmd/vendor/golang.org/x/tools/go/analysis/passes/asmdecl.s               37029    36822    -207    -0.559%
cmd/vendor/golang.org/x/tools/go/analysis/passes/inspect.s               340      337      -3      -0.882%
cmd/vendor/golang.org/x/tools/go/analysis/passes/cgocall.s               9919     9858     -61     -0.615%
cmd/vendor/golang.org/x/tools/go/analysis/passes/bools.s                 6705     6690     -15     -0.224%
cmd/vendor/golang.org/x/tools/go/analysis/passes/copylock.s              9783     9741     -42     -0.429%
cmd/vendor/golang.org/x/tools/go/cfg.s                                   31699    30742    -957    -3.019%
cmd/vendor/golang.org/x/tools/go/analysis/passes/ifaceassert.s           2768     2762     -6      -0.217%
cmd/vendor/golang.org/x/tools/go/analysis/passes/loopclosure.s           3031     2998     -33     -1.089%
cmd/vendor/golang.org/x/tools/go/analysis/passes/shift.s                 4382     4376     -6      -0.137%
cmd/vendor/golang.org/x/tools/go/analysis/passes/stdmethods.s            8654     8642     -12     -0.139%
cmd/vendor/golang.org/x/tools/go/analysis/passes/stringintconv.s         3458     3446     -12     -0.347%
cmd/vendor/golang.org/x/tools/go/analysis/passes/structtag.s             8011     7995     -16     -0.200%
cmd/vendor/golang.org/x/tools/go/analysis/passes/tests.s                 6205     6193     -12     -0.193%
cmd/vendor/golang.org/x/tools/go/ast/astutil.s                           66183    65861    -322    -0.487%
cmd/vendor/github.com/google/pprof/profile.s                             150844   150261   -583    -0.386%
cmd/vendor/golang.org/x/tools/go/analysis/passes/unreachable.s           8057     8054     -3      -0.037%
cmd/vendor/golang.org/x/tools/go/analysis/passes/unusedresult.s          3670     3667     -3      -0.082%
cmd/vendor/github.com/google/pprof/internal/measurement.s                10464    10440    -24     -0.229%
cmd/vendor/golang.org/x/tools/go/types/typeutil.s                        12319    12274    -45     -0.365%
cmd/vendor/golang.org/x/tools/go/analysis/unitchecker.s                  13503    13342    -161    -1.192%
cmd/vendor/golang.org/x/tools/go/analysis/passes/ctrlflow.s              5261     5218     -43     -0.817%
cmd/vendor/golang.org/x/tools/go/analysis/passes/errorsas.s              1462     1459     -3      -0.205%
cmd/vendor/golang.org/x/tools/go/analysis/passes/lostcancel.s            9594     9582     -12     -0.125%
cmd/vendor/golang.org/x/tools/go/analysis/passes/printf.s                34397    34338    -59     -0.172%
cmd/vendor/github.com/google/pprof/internal/graph.s                      53225    52936    -289    -0.543%
cmd/vendor/github.com/ianlancetaylor/demangle.s                          177450   175329   -2121   -1.195%
crypto/x509.s                                                            147892   147388   -504    -0.341%
cmd/go/internal/work.s                                                   306465   304950   -1515   -0.494%
cmd/go/internal/run.s                                                    4664     4657     -7      -0.150%
crypto/tls.s                                                             313130   311833   -1297   -0.414%
net/http/httptrace.s                                                     3979     3905     -74     -1.860%
net/smtp.s                                                               14413    14344    -69     -0.479%
cmd/link/internal/ld.s                                                   545343   542279   -3064   -0.562%
cmd/link/internal/mips.s                                                 6218     6215     -3      -0.048%
cmd/link/internal/mips64.s                                               6108     6103     -5      -0.082%
cmd/link/internal/amd64.s                                                18154    18112    -42     -0.231%
cmd/link/internal/arm64.s                                                22527    22494    -33     -0.146%
cmd/link/internal/arm.s                                                  22574    22494    -80     -0.354%
cmd/link/internal/s390x.s                                                20779    20746    -33     -0.159%
cmd/link/internal/wasm.s                                                 16531    16493    -38     -0.230%
cmd/link/internal/x86.s                                                  18906    18849    -57     -0.301%
cmd/link/internal/ppc64.s                                                26856    26778    -78     -0.290%
net/http.s                                                               559101   556513   -2588   -0.463%
net/http/cookiejar.s                                                     15912    15885    -27     -0.170%
expvar.s                                                                 9531     9525     -6      -0.063%
net/http/httptest.s                                                      16616    16475    -141    -0.849%
net/http/cgi.s                                                           23624    23458    -166    -0.703%
cmd/go/internal/web.s                                                    16546    16489    -57     -0.344%
cmd/vendor/golang.org/x/mod/sumdb.s                                      33197    33117    -80     -0.241%
net/http/fcgi.s                                                          19266    19169    -97     -0.503%
net/http/httputil.s                                                      39875    39728    -147    -0.369%
cmd/vendor/github.com/google/pprof/internal/symbolz.s                    5888     5867     -21     -0.357%
net/rpc.s                                                                34154    34003    -151    -0.442%
cmd/vendor/github.com/google/pprof/internal/transport.s                  2746     2716     -30     -1.092%
cmd/vendor/github.com/google/pprof/internal/binutils.s                   35999    35875    -124    -0.344%
net/rpc/jsonrpc.s                                                        6637     6598     -39     -0.588%
cmd/vendor/github.com/google/pprof/internal/symbolizer.s                 11533    11458    -75     -0.650%
cmd/go/internal/get.s                                                    62921    62803    -118    -0.188%
cmd/vendor/github.com/google/pprof/internal/report.s                     80364    80058    -306    -0.381%
cmd/go/internal/modfetch/codehost.s                                      89680    89066    -614    -0.685%
cmd/trace.s                                                              117171   116701   -470    -0.401%
cmd/vendor/github.com/google/pprof/internal/driver.s                     144268   143297   -971    -0.673%
cmd/go/internal/modfetch.s                                               126299   125860   -439    -0.348%
cmd/vendor/github.com/google/pprof/driver.s                              9042     9000     -42     -0.464%
cmd/go/internal/modconv.s                                                17947    17889    -58     -0.323%
cmd/pprof.s                                                              12399    12326    -73     -0.589%
cmd/go/internal/modload.s                                                151182   150389   -793    -0.525%
cmd/go/internal/generate.s                                               11738    11636    -102    -0.869%
cmd/go/internal/help.s                                                   6571     6531     -40     -0.609%
cmd/go/internal/clean.s                                                  11174    11142    -32     -0.286%
cmd/go/internal/vet.s                                                    7897     7867     -30     -0.380%
cmd/go/internal/envcmd.s                                                 22176    22095    -81     -0.365%
cmd/go/internal/list.s                                                   15216    15067    -149    -0.979%
cmd/go/internal/modget.s                                                 38698    38519    -179    -0.463%
cmd/go/internal/modcmd.s                                                 46674    46441    -233    -0.499%
cmd/go/internal/test.s                                                   64664    64456    -208    -0.322%
cmd/go.s                                                                 6730     6703     -27     -0.401%
cmd/compile/internal/ssa.s                                               3592565  3582500  -10065  -0.280%
cmd/compile/internal/gc.s                                                1549123  1537123  -12000  -0.775%
cmd/compile/internal/riscv64.s                                           14579    14483    -96     -0.658%
cmd/compile/internal/mips.s                                              20578    20419    -159    -0.773%
cmd/compile/internal/ppc64.s                                             25524    25359    -165    -0.646%
cmd/compile/internal/mips64.s                                            19795    19636    -159    -0.803%
cmd/compile/internal/wasm.s                                              13329    13290    -39     -0.293%
cmd/compile/internal/s390x.s                                             28097    27892    -205    -0.730%
cmd/compile/internal/arm.s                                               31489    31321    -168    -0.534%
cmd/compile/internal/arm64.s                                             29803    29590    -213    -0.715%
cmd/compile/internal/amd64.s                                             32961    33221    +260    +0.789%
cmd/compile/internal/x86.s                                               31029    30878    -151    -0.487%
total                                                                    18534966 18440341 -94625  -0.511%

Change-Id: I830d37364f14f0297800adc42c99f60a74c51aca
Reviewed-on: https://go-review.googlesource.com/c/go/+/226367
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
 2020-03-31 21:26:33 +00:00
Keith Randall
33b648c0e9 cmd/compile: fix ephemeral pointer problem on amd64 
Make sure we don't use the rewrite ptr + (c + x) -> c + (ptr + x), as
that may create an ephemeral out-of-bounds pointer.

I have not seen an actual bug caused by this yet, but we've seen
them in the 386 port so I'm fixing this issue for amd64 as well.

The load-combining rules needed to be reworked somewhat to still
work without the above broken rule.

Update #37881

Change-Id: I8046d170e89e2035195f261535e34ca7d8aca68a
Reviewed-on: https://go-review.googlesource.com/c/go/+/226437
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
 2020-03-30 17:25:29 +00:00
Keith Randall
af7eafd150 cmd/compile: convert 386 port to use addressing modes pass (take 2) 
Retrying CL 222782, with a fix that will hopefully stop the random crashing.

The issue with the previous CL is that it does pointer arithmetic
in a way that may briefly generate an out-of-bounds pointer. If an
interrupt happens to occur in that state, the referenced object may
be collected incorrectly.

Suppose there was code that did s[x+c].  The previous CL had a rule
to the effect of ptr + (x + c) -> c + (ptr + x).  But ptr+x is not
guaranteed to point to the same object as ptr. In contrast,
ptr+(x+c) is guaranteed to point to the same object as ptr, because
we would have already checked that x+c is in bounds.

For example, strconv.trim used to have this code:
  MOVZX -0x1(BX)(DX*1), BP
  CMPL $0x30, AL
After CL 222782, it had this code:
  LEAL 0(BX)(DX*1), BP
  CMPB $0x30, -0x1(BP)

An interrupt between those last two instructions could see BP pointing
outside the backing store of the slice involved.

It's really hard to actually demonstrate a bug. First, you need to
have an interrupt occur at exactly the right time. Then, there must
be no other pointers to the object in question. Since the interrupted
frame will be scanned conservatively, there can't even be a dead
pointer in another register or on the stack. (In the example above,
a bug can't happen because BX still holds the original pointer.)
Then, the object in question needs to be collected (or at least
scanned?) before the interrupted code continues.

This CL needs to handle load combining somewhat differently than CL 222782
because of the new restriction on arithmetic. That's the only real
difference (other than removing the bad rules) from that old CL.

This bug is also present in the amd64 rewrite rules, and we haven't
seen any crashing as a result. I will fix up that code similarly to
this one in a separate CL.

Update #37881

Change-Id: I5f0d584d9bef4696bfe89a61ef0a27c8d507329f
Reviewed-on: https://go-review.googlesource.com/c/go/+/225798
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
 2020-03-27 18:54:45 +00:00
Lynn Boger
e4a1cf8a56 cmd/compile: add rules to eliminate unnecessary signed shifts 
This change to the rules removes some unnecessary signed shifts
that appear in the math/rand functions. Existing rules did not
cover some of the signed cases.

A little improvement seen in math/rand due to removing 1 of 2
instructions generated for Int31n, which is inlined quite a bit.

Intn1000                 46.9ns ± 0%  45.5ns ± 0%   -2.99%  (p=1.000 n=1+1)
Int63n1000               33.5ns ± 0%  32.8ns ± 0%   -2.09%  (p=1.000 n=1+1)
Int31n1000               32.7ns ± 0%  32.6ns ± 0%   -0.31%  (p=1.000 n=1+1)
Float32                  32.7ns ± 0%  30.3ns ± 0%   -7.34%  (p=1.000 n=1+1)
Float64                  21.7ns ± 0%  20.9ns ± 0%   -3.69%  (p=1.000 n=1+1)
Perm3                     205ns ± 0%   202ns ± 0%   -1.46%  (p=1.000 n=1+1)
Perm30                   1.71µs ± 0%  1.68µs ± 0%   -1.35%  (p=1.000 n=1+1)
Perm30ViaShuffle         1.65µs ± 0%  1.65µs ± 0%   -0.30%  (p=1.000 n=1+1)
ShuffleOverhead          2.83µs ± 0%  2.83µs ± 0%   -0.07%  (p=1.000 n=1+1)
Read3                    18.7ns ± 0%  16.1ns ± 0%  -13.90%  (p=1.000 n=1+1)
Read64                    126ns ± 0%   124ns ± 0%   -1.59%  (p=1.000 n=1+1)
Read1000                 1.75µs ± 0%  1.63µs ± 0%   -7.08%  (p=1.000 n=1+1)

Change-Id: I11502dfca7d65aafc76749a8d713e9e50c24a858
Reviewed-on: https://go-review.googlesource.com/c/go/+/225917
Run-TryBot: Lynn Boger <laboger@linux.vnet.ibm.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
 2020-03-27 16:05:42 +00:00
Ruixin(Peter) Bao
16cfab8d89 cmd/compile: use load and test instructions on s390x 
The load and test instructions compare the given value
against zero and will produce a condition code indicating
one of the following scenarios:

0: Result is zero
1: Result is less than zero
2: Result is greater than zero
3: Result is not a number (NaN)

The instruction can be used to simplify floating point comparisons
against zero, which can enable further optimizations.

This CL also reduces the size of .text section of math.test binary by around
0.7 KB (in hexadecimal, from 1358f0 to 135620).

Change-Id: I33cb714f0c6feebac7a1c46dfcc735e7daceff9c
Reviewed-on: https://go-review.googlesource.com/c/go/+/209159
Reviewed-by: Michael Munday <mike.munday@ibm.com>
Run-TryBot: Michael Munday <mike.munday@ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
 2020-03-25 13:10:07 +00:00
Keith Randall
c785633941 Revert "cmd/compile: convert 386 port to use addressing modes pass" 
This reverts commit CL 222782.

Reason for revert: Reverting to see if 386 errors go away

Update #37881

Change-Id: I74f287404c52414db1b6ff1649effa4ed9e5cc0c
Reviewed-on: https://go-review.googlesource.com/c/go/+/225218
Reviewed-by: Bryan C. Mills <bcmills@google.com>
 2020-03-24 19:07:15 +00:00
Keith Randall
e0deacd1c0 Revert "cmd/compile: disable mem+op operations on 386" 
This reverts commit CL 224837.

Reason for revert: Reverting partial reverts of 222782.

Update #37881

Change-Id: Ie9bf84d6e17ed214abe538965e5ff03936886826
Reviewed-on: https://go-review.googlesource.com/c/go/+/225217
Reviewed-by: Bryan C. Mills <bcmills@google.com>
 2020-03-24 19:06:22 +00:00
Keith Randall
f975485ad1 Revert "cmd/compile: disable addressingmodes pass for 386" 
This reverts commit CL 225057.

Reason for revert: Undoing partial reverts of CL 222782

Update #37881

Change-Id: Iee024cab2a580a37a0fc355e0e3c5ad3d8fdaf7d
Reviewed-on: https://go-review.googlesource.com/c/go/+/225197
Reviewed-by: Bryan C. Mills <bcmills@google.com>
 2020-03-24 19:05:50 +00:00
Keith Randall
5b897ec017 cmd/compile: disable addressingmodes pass for 386 
Update #37881

Change-Id: I1f9a3f57f6215a19c31765c257ee78715eab36b7
Reviewed-on: https://go-review.googlesource.com/c/go/+/225057
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
 2020-03-23 20:31:13 +00:00
Keith Randall
3adbdb6d99 cmd/compile: disable mem+op operations on 386 
Rolling back portions of CL 222782 to see if that helps
issue #37881 any.

Update #37881

Change-Id: I9cc3ff8c469fa5e4b22daec715d04148033f46f7
Reviewed-on: https://go-review.googlesource.com/c/go/+/224837
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
 2020-03-23 18:27:37 +00:00
Russ Cox
fc8a6336d1 cmd/asm, cmd/compile, runtime: add -spectre=ret mode 
This commit extends the -spectre flag to cmd/asm and adds
a new Spectre mitigation mode "ret", which enables the use
of retpolines.

Retpolines prevent speculation about the target of an indirect
jump or call and are described in more detail here:
https://support.google.com/faqs/answer/7625886

Change-Id: I4f2cb982fa94e44d91e49bd98974fd125619c93a
Reviewed-on: https://go-review.googlesource.com/c/go/+/222661
Reviewed-by: Keith Randall <khr@golang.org>
 2020-03-13 19:05:54 +00:00
Russ Cox
877ef86bec cmd/compile: add spectre mitigation mode enabled by -spectre 
This commit adds a new cmd/compile flag -spectre,
which accepts a comma-separated list of possible
Spectre mitigations to apply, or the empty string (none),
or "all". The only known mitigation right now is "index",
which uses conditional moves to ensure that x86-64 CPUs
do not speculate past index bounds checks.

Speculating past index bounds checks may be problematic
on systems running privileged servers that accept requests
from untrusted users who can execute their own programs
on the same machine. (And some more constraints that
make it even more unlikely in practice.)

The cases this protects against are analogous to the ones
Microsoft explains in the "Array out of bounds load/store feeding ..."
sections here:
https://docs.microsoft.com/en-us/cpp/security/developer-guidance-speculative-execution?view=vs-2019#array-out-of-bounds-load-feeding-an-indirect-branch

Change-Id: Ib7532d7e12466b17e04c4e2075c2a456dc98f610
Reviewed-on: https://go-review.googlesource.com/c/go/+/222660
Reviewed-by: Keith Randall <khr@golang.org>
 2020-03-13 19:05:46 +00:00
Keith Randall
d84cbec890 cmd/compile: convert 386 port to use addressing modes pass 
Update #36468

Change-Id: Idfdb845d097994689be450d6e8a57fa9adb57166
Reviewed-on: https://go-review.googlesource.com/c/go/+/222782
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
 2020-03-13 17:00:54 +00:00
Russ Cox
801a9d9a0c test/codegen: mention in README that tests only run on Linux without -all_codegen 
This took me a while to figure out. The relevant code is in
test/run.go (note the "linux" hard-coded strings):

	var arch, subarch, os string
	switch {
	case archspec[2] != "": // 3 components: "linux/386/sse2"
		os, arch, subarch = archspec[0], archspec[1][1:], archspec[2][1:]
	case archspec[1] != "": // 2 components: "386/sse2"
		os, arch, subarch = "linux", archspec[0], archspec[1][1:]
	default: // 1 component: "386"
		os, arch, subarch = "linux", archspec[0], ""
		if arch == "wasm" {
			os = "js"
		}
	}

Change-Id: I92ba280025d2072e17532a5e43cf1d676789c167
Reviewed-on: https://go-review.googlesource.com/c/go/+/222819
Reviewed-by: Keith Randall <khr@golang.org>
 2020-03-11 16:17:08 +00:00
Keith Randall
98cb76799c cmd/compile: insert complicated x86 addressing modes as a separate pass 
Use a separate compiler pass to introduce complicated x86 addressing
modes.  Loads in the normal architecture rules (for x86 and all other
platforms) can have constant offsets (AuxInt values) and symbols (Aux
values), but no more.

The complex addressing modes (x+y, x+2*y, etc.) are introduced in a
separate pass that combines loads with LEAQx ops.

Organizing rewrites this way simplifies the number of rewrites
required, as there are lots of different rule orderings that have to
be specified to ensure these complex addressing modes are always found
if they are possible.

Update #36468

Change-Id: I5b4bf7b03a1e731d6dfeb9ef19b376175f3b4b44
Reviewed-on: https://go-review.googlesource.com/c/go/+/217097
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
 2020-03-10 00:13:21 +00:00
Diogo Pinela
19ed0d993c cmd/compile: use staticuint64s instead of staticbytes 
There are still two places in src/runtime/string.go that use
staticbytes, so we cannot delete it just yet.

There is a new codegen test to verify that the index calculation
is constant-folded, at least on amd64. ppc64, mips[64] and s390x
cannot currently do that.

There is also a new runtime benchmark to ensure that this does not
slow down performance (tested against parent commit):

name                      old time/op  new time/op  delta
ConvT2EByteSized/bool-4   1.07ns ± 1%  1.07ns ± 1%   ~     (p=0.060 n=14+15)
ConvT2EByteSized/uint8-4  1.06ns ± 1%  1.07ns ± 1%   ~     (p=0.095 n=14+15)

Updates #37612

Change-Id: I5ec30738edaa48cda78dfab4a78e24a32fa7fd6a
Reviewed-on: https://go-review.googlesource.com/c/go/+/221957
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
 2020-03-04 21:43:01 +00:00
Keith Randall
cd9fd640db cmd/compile: don't allow NaNs in floating-point constant ops 
Trying this CL again, with a fixed test that allows platforms
to disagree on the exact behavior of converting NaNs.

We store 32-bit floating point constants in a 64-bit field, by
converting that 32-bit float to 64-bit float to store it, and convert
it back to use it.

That works for *almost* all floating-point constants. The exception is
signaling NaNs. The round trip described above means we can't represent
a 32-bit signaling NaN, because conversions strip the signaling bit.

To fix this issue, just forbid NaNs as floating-point constants in SSA
form. This shouldn't affect any real-world code, as people seldom
constant-propagate NaNs (except in test code).

Additionally, NaNs are somewhat underspecified (which of the many NaNs
do you get when dividing 0/0?), so when cross-compiling there's a
danger of using the compiler machine's NaN regime for some math, and
the target machine's NaN regime for other math. Better to use the
target machine's NaN regime always.

Update #36400

Change-Id: Idf203b688a15abceabbd66ba290d4e9f63619ecb
Reviewed-on: https://go-review.googlesource.com/c/go/+/221790
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
 2020-03-04 04:49:54 +00:00
Josh Bleecher Snyder
b49d8ce2fa all: fix two minor typos in comments 
Change-Id: Iec6cd81c9787d3419850aa97e75052956ad139bc
Reviewed-on: https://go-review.googlesource.com/c/go/+/221789
Reviewed-by: Emmanuel Odeke <emm.odeke@gmail.com>
 2020-03-03 17:44:05 +00:00
Michael Munday
e37cc29863 cmd/compile: optimize integer-in-range checks 
This CL incorporates code from CL 201206 by Josh Bleecher Snyder
(thanks Josh).

This CL restores the integer-in-range optimizations in the SSA
backend. The fuse pass is enhanced to detect inequalities that
could be merged and fuse their associated blocks while the generic
rules optimize them into a single unsigned comparison.

For example, the inequality `x >= 0 && x < 10` will now be optimized
to `unsigned(x) < 10`.

Overall has a fairly positive impact on binary sizes.

name                      old time/op       new time/op       delta
Template                        192ms ± 1%        192ms ± 1%    ~     (p=0.757 n=17+18)
Unicode                        76.6ms ± 2%       76.5ms ± 2%    ~     (p=0.603 n=19+19)
GoTypes                         694ms ± 1%        693ms ± 1%    ~     (p=0.569 n=19+20)
Compiler                        3.26s ± 0%        3.27s ± 0%  +0.25%  (p=0.000 n=20+20)
SSA                             7.41s ± 0%        7.49s ± 0%  +1.10%  (p=0.000 n=17+19)
Flate                           120ms ± 1%        120ms ± 1%  +0.38%  (p=0.003 n=19+19)
GoParser                        152ms ± 1%        152ms ± 1%    ~     (p=0.061 n=17+19)
Reflect                         422ms ± 1%        425ms ± 2%  +0.76%  (p=0.001 n=18+20)
Tar                             167ms ± 1%        167ms ± 0%    ~     (p=0.730 n=18+19)
XML                             233ms ± 4%        231ms ± 1%    ~     (p=0.752 n=20+17)
LinkCompiler                    927ms ± 8%        928ms ± 8%    ~     (p=0.857 n=19+20)
ExternalLinkCompiler            1.81s ± 2%        1.81s ± 2%    ~     (p=0.513 n=19+20)
LinkWithoutDebugCompiler        556ms ±10%        583ms ±13%  +4.95%  (p=0.007 n=20+20)
[Geo mean]                      478ms             481ms       +0.52%

name                      old user-time/op  new user-time/op  delta
Template                        270ms ± 5%        269ms ± 7%    ~     (p=0.925 n=20+20)
Unicode                         134ms ± 7%        131ms ±14%    ~     (p=0.593 n=18+20)
GoTypes                         981ms ± 3%        987ms ± 2%  +0.63%  (p=0.049 n=19+18)
Compiler                        4.50s ± 2%        4.50s ± 1%    ~     (p=0.588 n=19+20)
SSA                             10.6s ± 2%        10.6s ± 1%    ~     (p=0.141 n=20+19)
Flate                           164ms ± 8%        165ms ±10%    ~     (p=0.738 n=20+20)
GoParser                        202ms ± 5%        203ms ± 6%    ~     (p=0.820 n=20+20)
Reflect                         587ms ± 6%        597ms ± 3%    ~     (p=0.087 n=20+18)
Tar                             230ms ± 6%        228ms ± 8%    ~     (p=0.569 n=19+20)
XML                             311ms ± 6%        314ms ± 5%    ~     (p=0.369 n=20+20)
LinkCompiler                    878ms ± 8%        887ms ± 7%    ~     (p=0.289 n=20+20)
ExternalLinkCompiler            1.60s ± 7%        1.60s ± 7%    ~     (p=0.820 n=20+20)
LinkWithoutDebugCompiler        498ms ±12%        489ms ±11%    ~     (p=0.398 n=20+20)
[Geo mean]                      611ms             611ms       +0.05%

name                      old alloc/op      new alloc/op      delta
Template                       36.1MB ± 0%       36.0MB ± 0%  -0.32%  (p=0.000 n=20+20)
Unicode                        28.3MB ± 0%       28.3MB ± 0%  -0.03%  (p=0.000 n=19+20)
GoTypes                         121MB ± 0%        121MB ± 0%    ~     (p=0.226 n=16+20)
Compiler                        563MB ± 0%        563MB ± 0%    ~     (p=0.166 n=20+19)
SSA                            1.32GB ± 0%       1.33GB ± 0%  +0.88%  (p=0.000 n=20+19)
Flate                          22.7MB ± 0%       22.7MB ± 0%  -0.02%  (p=0.033 n=19+20)
GoParser                       27.9MB ± 0%       27.9MB ± 0%  -0.02%  (p=0.001 n=20+20)
Reflect                        78.3MB ± 0%       78.2MB ± 0%  -0.01%  (p=0.019 n=20+20)
Tar                            34.0MB ± 0%       34.0MB ± 0%  -0.04%  (p=0.000 n=20+20)
XML                            43.9MB ± 0%       43.9MB ± 0%  -0.07%  (p=0.000 n=20+19)
LinkCompiler                    205MB ± 0%        205MB ± 0%  +0.44%  (p=0.000 n=20+18)
ExternalLinkCompiler            223MB ± 0%        223MB ± 0%  +0.03%  (p=0.000 n=20+20)
LinkWithoutDebugCompiler        139MB ± 0%        142MB ± 0%  +1.75%  (p=0.000 n=20+20)
[Geo mean]                     93.7MB            93.9MB       +0.20%

name                      old allocs/op     new allocs/op     delta
Template                         363k ± 0%         361k ± 0%  -0.58%  (p=0.000 n=20+19)
Unicode                          329k ± 0%         329k ± 0%  -0.06%  (p=0.000 n=19+20)
GoTypes                         1.28M ± 0%        1.28M ± 0%  -0.01%  (p=0.000 n=20+20)
Compiler                        5.40M ± 0%        5.40M ± 0%  -0.01%  (p=0.000 n=20+20)
SSA                             12.7M ± 0%        12.8M ± 0%  +0.80%  (p=0.000 n=20+20)
Flate                            228k ± 0%         228k ± 0%    ~     (p=0.194 n=20+20)
GoParser                         295k ± 0%         295k ± 0%  -0.04%  (p=0.000 n=20+20)
Reflect                          949k ± 0%         949k ± 0%  -0.01%  (p=0.000 n=20+20)
Tar                              337k ± 0%         337k ± 0%  -0.06%  (p=0.000 n=20+20)
XML                              418k ± 0%         417k ± 0%  -0.17%  (p=0.000 n=20+20)
LinkCompiler                     553k ± 0%         554k ± 0%  +0.22%  (p=0.000 n=20+19)
ExternalLinkCompiler            1.52M ± 0%        1.52M ± 0%  +0.27%  (p=0.000 n=20+20)
LinkWithoutDebugCompiler         186k ± 0%         186k ± 0%  +0.06%  (p=0.000 n=20+20)
[Geo mean]                       723k              723k       +0.03%

name                      old text-bytes    new text-bytes    delta
HelloSize                       828kB ± 0%        828kB ± 0%  -0.01%  (p=0.000 n=20+20)

name                      old data-bytes    new data-bytes    delta
HelloSize                      13.4kB ± 0%       13.4kB ± 0%    ~     (all equal)

name                      old bss-bytes     new bss-bytes     delta
HelloSize                       180kB ± 0%        180kB ± 0%    ~     (all equal)

name                      old exe-bytes     new exe-bytes     delta
HelloSize                      1.23MB ± 0%       1.23MB ± 0%  -0.33%  (p=0.000 n=20+20)

file      before    after     Δ       %
addr2line 4320075   4311883   -8192   -0.190%
asm       5191932   5187836   -4096   -0.079%
buildid   2835338   2831242   -4096   -0.144%
compile   20531717  20569099  +37382  +0.182%
cover     5322511   5318415   -4096   -0.077%
dist      3723749   3719653   -4096   -0.110%
doc       4743515   4739419   -4096   -0.086%
fix       3413960   3409864   -4096   -0.120%
link      6690119   6686023   -4096   -0.061%
nm        4269616   4265520   -4096   -0.096%
pprof     14942189  14929901  -12288  -0.082%
trace     11807164  11790780  -16384  -0.139%
vet       8384104   8388200   +4096   +0.049%
go        15339076  15334980  -4096   -0.027%
total     132258257 132226007 -32250  -0.024%

Fixes #30645.

Change-Id: If551ac5996097f3685870d083151b5843170aab0
Reviewed-on: https://go-review.googlesource.com/c/go/+/165998
Run-TryBot: Michael Munday <mike.munday@ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
 2020-03-03 14:30:26 +00:00
Michael Munday
44fe355694 cmd/compile: canonicalize comparison argument order 
Ensure that any comparison between two values has the same argument
order. This helps ensure that they can be eliminated during the
lowered CSE pass which will be particularly important if we eliminate
the Greater and Geq ops (see #37316).

Example:

  CMP R0, R1
  BLT L1
  CMP R1, R0 // different order, cannot eliminate
  BEQ L2

  CMP R0, R1
  BLT L1
  CMP R0, R1 // same order, can eliminate
  BEQ L2

This does have some drawbacks. Notably comparisons might 'flip'
direction in the assembly output after even small changes to the
code or compiler. It should help make optimizations more reliable
however.

compilecmp master -> HEAD
master (218f4572f5): text/template: make reflect.Value indirections more robust
HEAD (f1661fef3e): cmd/compile: canonicalize comparison argument order
platform: linux/amd64

file      before    after     Δ       %
api       6063927   6068023   +4096   +0.068%
asm       5191757   5183565   -8192   -0.158%
cgo       4893518   4901710   +8192   +0.167%
cover     5330345   5326249   -4096   -0.077%
fix       3417778   3421874   +4096   +0.120%
pprof     14889456  14885360  -4096   -0.028%
test2json 2848138   2844042   -4096   -0.144%
trace     11746239  11733951  -12288  -0.105%
total     132739173 132722789 -16384  -0.012%

Change-Id: I11736b3fe2a4553f6fc65018f475e88217fa22f9
Reviewed-on: https://go-review.googlesource.com/c/go/+/220425
Run-TryBot: Michael Munday <mike.munday@ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
 2020-02-26 10:32:22 +00:00
Bryan C. Mills
a9f1ea4a83 Revert "cmd/compile: don't allow NaNs in floating-point constant ops" 
This reverts CL 213477.

Reason for revert: tests are failing on linux-mips*-rtrk builders.

Change-Id: I8168f7450890233f1bd7e53930b73693c26d4dc0
Reviewed-on: https://go-review.googlesource.com/c/go/+/220897
Run-TryBot: Bryan C. Mills <bcmills@google.com>
Reviewed-by: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
 2020-02-25 15:49:19 +00:00
Keith Randall
2aa7c6c548 cmd/compile: don't allow NaNs in floating-point constant ops 
We store 32-bit floating point constants in a 64-bit field, by
converting that 32-bit float to 64-bit float to store it, and convert
it back to use it.

That works for *almost* all floating-point constants. The exception is
signaling NaNs. The round trip described above means we can't represent
a 32-bit signaling NaN, because conversions strip the signaling bit.

To fix this issue, just forbid NaNs as floating-point constants in SSA
form. This shouldn't affect any real-world code, as people seldom
constant-propagate NaNs (except in test code).

Additionally, NaNs are somewhat underspecified (which of the many NaNs
do you get when dividing 0/0?), so when cross-compiling there's a
danger of using the compiler machine's NaN regime for some math, and
the target machine's NaN regime for other math. Better to use the
target machine's NaN regime always.

This has been a bug since 1.10, and there's an easy workaround
(declare a global varaible containing the signaling NaN pattern, and
use that as the argument to math.Float32frombits) so we'll fix it in
1.15.

Fixes #36400
Update #36399

Change-Id: Icf155e743281560eda2eed953d19a829552ccfda
Reviewed-on: https://go-review.googlesource.com/c/go/+/213477
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
 2020-02-25 02:21:53 +00:00
Keith Randall
1cfe8e91b6 cmd/compile: use ADDQ instead of LEAQ when we can 
The address calculations in the example end up doing x << 4 + y + 0.
Before this CL we use a SHLQ+LEAQ. Since the constant offset is 0,
we can use SHLQ+ADDQ instead.

Change-Id: Ia048c4fdbb3a42121c7e1ab707961062e8247fca
Reviewed-on: https://go-review.googlesource.com/c/go/+/209959
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
 2020-02-24 21:33:53 +00:00
Brian Kessler
6b1d5471b9 cmd/compile: add signed indivisibility by power of 2 rules 
Commit 44343c777c (CL 173557) added rules for handling
divisibility checks for powers of 2 for signed integers, x%c ==0.
This change adds the complementary indivisibility rules, x%c != 0.

Fixes #34166

Change-Id: I87379e30af7aff633371acca82db2397da9b2c07
Reviewed-on: https://go-review.googlesource.com/c/go/+/194219
Run-TryBot: Brian Kessler <brian.m.kessler@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
 2019-11-07 16:30:46 +00:00
Russ Cox
543c6d2e0d math, cmd/compile: rename Fma to FMA 
This API was added for #25819, where it was discussed as math.FMA.
The commit adding it used math.Fma, presumably for consistency
with the rest of the unusual names in package math
(Sincos, Acosh, Erfcinv, Float32bits, etc).

I believe that using an idiomatic Go name is more important here
than consistency with these other names, most of which are historical
baggage from C's standard library.

Early additions like Float32frombits happened before "uppercase for export"
(so they were originally like "float32frombits") and they were not properly
reconsidered when we uppercased the symbols to export them.
That's a mistake we live with.

The names of functions we have added since then, and even a few
that were legacy, are more properly Go-cased, such as IsNaN, IsInf,
and RoundToEven, rather than Isnan, Isinf, and Roundtoeven.
And also constants like MaxFloat32.

For new API, we should keep using proper Go-cased symbols
instead of minimally-upper-cased-C symbols.

So math.FMA, not math.Fma.

This API has not yet been released, so this change does not break
the compatibility promise.

This CL also modifies cmd/compile, since the compiler knows
the name of the function. I could have stopped at changing the
string constants, but it seemed to make more sense to use a
consistent casing everywhere.

Change-Id: I0f6f3407f41e99bfa8239467345c33945088896e
Reviewed-on: https://go-review.googlesource.com/c/go/+/205317
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
 2019-11-07 14:51:06 +00:00
smasher164
58b031949b cmd/compile: add fma intrinsic for arm 
This change introduces an arm intrinsic that generates the FMULAD
instruction for the fused-multiply-add operation on systems that
support it. System support is detected via cpu.ARM.HasVFPv4. A rewrite
rule translates the generic intrinsic to FMULAD.

Updates #25819.

Change-Id: I8459e5dd1cdbdca35f88a78dbeb7d387f1e20efa
Reviewed-on: https://go-review.googlesource.com/c/go/+/142117
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
 2019-10-21 17:42:47 +00:00
smasher164
7a6da218b1 cmd/compile: add fma intrinsic for amd64 
To permit ssa-level optimization, this change introduces an amd64 intrinsic
that generates the VFMADD231SD instruction for the fused-multiply-add
operation on systems that support it. System support is detected via
cpu.X86.HasFMA. A rewrite rule can then translate the generic ssa intrinsic
("Fma") to VFMADD231SD.

The benchmark compares the software implementation (old) with the intrinsic
(new).

name   old time/op  new time/op  delta
Fma-4  27.2ns ± 1%   1.0ns ± 9%  -96.48%  (p=0.008 n=5+5)

Updates #25819.

Change-Id: I966655e5f96817a5d06dff5942418a3915b09584
Reviewed-on: https://go-review.googlesource.com/c/go/+/137156
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
 2019-10-21 16:42:10 +00:00
smasher164
33425ab8db cmd/compile: introduce generic ssa intrinsic for fused-multiply-add 
In order to make math.FMA a compiler intrinsic for ISAs like ARM64,
PPC64[le], and S390X, a generic 3-argument opcode "Fma" is provided and
rewritten as

    ARM64: (Fma x y z) -> (FMADDD z x y)
    PPC64: (Fma x y z) -> (FMADD x y z)
    S390X: (Fma x y z) -> (FMADD z x y)

Updates #25819.

Change-Id: Ie5bc628311e6feeb28ddf9adaa6e702c8c291efa
Reviewed-on: https://go-review.googlesource.com/c/go/+/131959
Run-TryBot: Akhil Indurti <aindurti@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
 2019-10-21 16:24:15 +00:00
David Chase
6adaf17eaa cmd/compile: preserve statements in late nilcheckelim optimization 
When a subsequent load/store of a ptr makes the nil check of that pointer
unnecessary, if their lines differ, change the line of the load/store
to that of the nilcheck, and attempt to rehome the load/store position
instead.

This fix makes profiling less accurate in order to make panics more
informative.

Fixes #33724

Change-Id: Ib9afaac12fe0d0320aea1bf493617facc34034b3
Reviewed-on: https://go-review.googlesource.com/c/go/+/200197
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
 2019-10-15 16:43:44 +00:00
Meng Zhuo
50f1157760 cmd/compile: add math/bits.Mul64 intrinsic on mips64x 
Benchmark:
name   old time/op  new time/op  delta
Mul    36.0ns ± 1%   2.8ns ± 0%  -92.31%  (p=0.000 n=10+10)
Mul32  4.37ns ± 0%  4.37ns ± 0%     ~     (p=0.429 n=6+10)
Mul64  36.4ns ± 0%   2.8ns ± 0%  -92.37%  (p=0.000 n=10+9)

Change-Id: Ic4f4e5958adbf24999abcee721d0180b5413fca7
Reviewed-on: https://go-review.googlesource.com/c/go/+/200582
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
 2019-10-14 21:23:34 +00:00
Michael Munday
6ec4c71eef cmd/compile: add SSA rules for s390x compare-and-branch instructions 
This commit adds SSA rules for the s390x combined compare-and-branch
instructions. These have a shorter encoding than separate compare
and branch instructions and they also don't clobber the condition
code (a.k.a. flag register) reducing pressure on the flag allocator.

I have deleted the 'loop_test.go' file and replaced it with a new
codegen test which performs a wider range of checks.

Object sizes from compilebench:

name                      old object-bytes  new object-bytes  delta
Template                        562kB ± 0%        561kB ± 0%   -0.28%  (p=0.000 n=10+10)
Unicode                         217kB ± 0%        217kB ± 0%   -0.17%  (p=0.000 n=10+10)
GoTypes                        2.03MB ± 0%       2.02MB ± 0%   -0.59%  (p=0.000 n=10+10)
Compiler                       8.16MB ± 0%       8.11MB ± 0%   -0.62%  (p=0.000 n=10+10)
SSA                            27.4MB ± 0%       27.0MB ± 0%   -1.45%  (p=0.000 n=10+10)
Flate                           356kB ± 0%        356kB ± 0%   -0.12%  (p=0.000 n=10+10)
GoParser                        438kB ± 0%        436kB ± 0%   -0.51%  (p=0.000 n=10+10)
Reflect                        1.37MB ± 0%       1.37MB ± 0%   -0.42%  (p=0.000 n=10+10)
Tar                             485kB ± 0%        483kB ± 0%   -0.39%  (p=0.000 n=10+10)
XML                             630kB ± 0%        621kB ± 0%   -1.45%  (p=0.000 n=10+10)
[Geo mean]                     1.14MB            1.13MB        -0.60%

name                      old text-bytes    new text-bytes    delta
HelloSize                       763kB ± 0%        754kB ± 0%   -1.30%  (p=0.000 n=10+10)
CmdGoSize                      10.7MB ± 0%       10.6MB ± 0%   -0.91%  (p=0.000 n=10+10)
[Geo mean]                     2.86MB            2.82MB        -1.10%

Change-Id: Ibca55d9c0aa1254aee69433731ab5d26a43a7c18
Reviewed-on: https://go-review.googlesource.com/c/go/+/198037
Run-TryBot: Michael Munday <mike.munday@ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
 2019-10-08 10:03:04 +00:00
Cuong Manh Le
77f5adba55 cmd/compile: don't use statictmps for small object in slice literal 
Fixes #21561

Change-Id: I89c59752060dd9570d17d73acbbaceaefce5d8ce
Reviewed-on: https://go-review.googlesource.com/c/go/+/197560
Run-TryBot: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
 2019-10-08 06:09:26 +00:00
Keith Randall
72dc9ab191 cmd/compile: reuse dead register before reusing register holding constant 
For commuting ops, check whether the second argument is dead before
checking if the first argument is rematerializeable. Reusing the register
holding a dead value is always best.

Fixes #33580

Change-Id: I7372cfc03d514e6774d2d9cc727a3e6bf6ce2657
Reviewed-on: https://go-review.googlesource.com/c/go/+/199559
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
 2019-10-07 15:16:26 +00:00
Dan Scales
225f484c88 misc, runtime, test: extra tests and benchmarks for defer 
Add a bunch of extra tests and benchmarks for defer, in preparation for new
low-cost (open-coded) implementation of defers (see #34481),

 - New file defer_test.go that tests a bunch more unusual defer scenarios,
   including things that might have problems for open-coded defers.
 - Additions to callers_test.go actually verifying what the stack trace looks like
   for various panic or panic-recover scenarios.
 - Additions to crash_test.go testing several more crash scenarios involving
   recursive panics.
 - New benchmark in runtime_test.go measuring speed of panic-recover
 - New CGo benchmark in cgo_test.go calling from Go to C back to Go that
   shows defer overhead

Updates #34481

Change-Id: I423523f3e05fc0229d4277dd00073289a5526188
Reviewed-on: https://go-review.googlesource.com/c/go/+/197017
Run-TryBot: Dan Scales <danscales@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
 2019-09-25 23:27:16 +00:00
Martin Möhrmann
f41451e7eb compile: prefer an AND instead of SHR+SHL instructions 
On modern 64bit CPUs a SHR, SHL or AND instruction take 1 cycle to execute.
A pair of shifts that operate on the same register will take 2 cycles
and needs to wait for the input register value to be available.

Large constants used to mask the high bits of a register with an AND
instruction can not be encoded as an immediate in the AND instruction
on amd64 and therefore need to be loaded into a register with a MOV
instruction.

However that MOV instruction is not dependent on the output register and
on many CPUs does not compete with the AND or shift instructions for
execution ports.

Using a pair of shifts to mask high bits instead of an AND to mask high
bits of a register has a shorter encoding and uses one less general
purpose register but is slower due to taking one clock cycle longer
if there is no register pressure that would make the AND variant need to
generate a spill.

For example the instructions emitted for (x & 1 << 63) before this CL are:
48c1ea3f                SHRQ $0x3f, DX
48c1e23f                SHLQ $0x3f, DX

after this CL the instructions are the same as GCC and LLVM use:
48b80000000000000080    MOVQ $0x8000000000000000, AX
4821d0                  ANDQ DX, AX

Some platforms such as arm64 already have SSA optimization rules to fuse
two shift instructions back into an AND.

Removing the general rule to rewrite AND to SHR+SHL speeds up this benchmark:

    var GlobalU uint

    func BenchmarkAndHighBits(b *testing.B) {
        x := uint(0)
        for i := 0; i < b.N; i++ {
                x &= 1 << 63
        }
        GlobalU = x
    }

amd64/darwin on Intel(R) Core(TM) i7-3520M CPU @ 2.90GHz:
name           old time/op  new time/op  delta
AndHighBits-4  0.61ns ± 6%  0.42ns ± 6%  -31.42%  (p=0.000 n=25+25):

'go run run.go -all_codegen -v codegen' passes  with following adjustments:

ARM64: The BFXIL pattern ((x << lc) >> rc | y & ac) needed adjustment
       since ORshiftRL generation fusing '>> rc' and '|' interferes
       with matching ((x << lc) >> rc) to generate UBFX. Previously
       ORshiftLL was created first using the shifts generated for (y & ac).

S390X: Add rules for abs and copysign to match use of AND instead of SHIFTs.

Updates #33826
Updates #32781

Change-Id: I5a59f6239660d53c029cd22dfb44ddf39f93a56c
Reviewed-on: https://go-review.googlesource.com/c/go/+/196810
Run-TryBot: Martin Möhrmann <moehrmann@google.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
 2019-09-24 20:30:59 +00:00
Bryan C. Mills
34fe8295c5 Revert "compile: prefer an AND instead of SHR+SHL instructions" 
This reverts CL 194297.

Reason for revert: introduced register allocation failures on PPC64LE builders.

Updates #33826
Updates #32781
Updates #34468

Change-Id: I7d0b55df8cdf8e7d2277f1814299b083c2692e48
Reviewed-on: https://go-review.googlesource.com/c/go/+/196957
Run-TryBot: Bryan C. Mills <bcmills@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Dmitri Shuralyov <dmitshur@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Martin Möhrmann <moehrmann@google.com>
 2019-09-23 15:20:12 +00:00
Martin Möhrmann
4e2b84ffc5 compile: prefer an AND instead of SHR+SHL instructions 
On modern 64bit CPUs a SHR, SHL or AND instruction take 1 cycle to execute.
A pair of shifts that operate on the same register will take 2 cycles
and needs to wait for the input register value to be available.

Large constants used to mask the high bits of a register with an AND
instruction can not be encoded as an immediate in the AND instruction
on amd64 and therefore need to be loaded into a register with a MOV
instruction.

However that MOV instruction is not dependent on the output register and
on many CPUs does not compete with the AND or shift instructions for
execution ports.

Using a pair of shifts to mask high bits instead of an AND to mask high
bits of a register has a shorter encoding and uses one less general
purpose register but is slower due to taking one clock cycle longer
if there is no register pressure that would make the AND variant need to
generate a spill.

For example the instructions emitted for (x & 1 << 63) before this CL are:
48c1ea3f                SHRQ $0x3f, DX
48c1e23f                SHLQ $0x3f, DX

after this CL the instructions are the same as GCC and LLVM use:
48b80000000000000080    MOVQ $0x8000000000000000, AX
4821d0                  ANDQ DX, AX

Some platforms such as arm64 already have SSA optimization rules to fuse
two shift instructions back into an AND.

Removing the general rule to rewrite AND to SHR+SHL speeds up this benchmark:

    var GlobalU uint

    func BenchmarkAndHighBits(b *testing.B) {
        x := uint(0)
        for i := 0; i < b.N; i++ {
                x &= 1 << 63
        }
        GlobalU = x
    }

amd64/darwin on Intel(R) Core(TM) i7-3520M CPU @ 2.90GHz:
name           old time/op  new time/op  delta
AndHighBits-4  0.61ns ± 6%  0.42ns ± 6%  -31.42%  (p=0.000 n=25+25):

'go run run.go -all_codegen -v codegen' passes  with following adjustments:

ARM64: The BFXIL pattern ((x << lc) >> rc | y & ac) needed adjustment
       since ORshiftRL generation fusing '>> rc' and '|' interferes
       with matching ((x << lc) >> rc) to generate UBFX. Previously
       ORshiftLL was created first using the shifts generated for (y & ac).

S390X: Add rules for abs and copysign to match use of AND instead of SHIFTs.

Updates #33826
Updates #32781

Change-Id: I43227da76b625de03fbc51117162b23b9c678cdb
Reviewed-on: https://go-review.googlesource.com/c/go/+/194297
Run-TryBot: Martin Möhrmann <martisch@uos.de>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
 2019-09-21 18:00:13 +00:00
Agniva De Sarker
ecc7dd5469 test/codegen: fix wasm codegen breakage 
i32.eqz instructions don't appear unless needed in if conditions anymore
after CL 195204. I forgot to run the codegen tests while submitting the CL.

Thanks to @martisch for catching it.

Fixes #34442

Change-Id: I177b064b389be48e39d564849714d7a8839be13e
Reviewed-on: https://go-review.googlesource.com/c/go/+/196580
Run-TryBot: Agniva De Sarker <agniva.quicksilver@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Martin Möhrmann <moehrmann@google.com>
 2019-09-21 16:31:44 +00:00
Matthew Dempsky
85fc765341 cmd/compile: optimize switch on strings 
When compiling expression switches, we try to optimize runs of
constants into binary searches. The ordering used isn't visible to the
application, so it's unimportant as long as we're consistent between
sorting and searching.

For strings, it's much cheaper to compare string lengths than strings
themselves, so instead of ordering strings by "si <= sj", we currently
order them by "len(si) < len(sj) || len(si) == len(sj) && si <= sj"
(i.e., the lexicographical ordering on the 2-tuple (len(s), s)).

However, it's also somewhat cheaper to compare strings for equality
(i.e., ==) than for ordering (i.e., <=). And if there were two or
three string constants of the same length in a switch statement, we
might unnecessarily emit ordering comparisons.

For example, given:

    switch s {
    case "", "1", "2", "3": // ordered by length then content
        goto L
    }

we currently compile this as:

    if len(s) < 1 || len(s) == 1 && s <= "1" {
        if s == "" { goto L }
        else if s == "1" { goto L }
    } else {
        if s == "2" { goto L }
        else if s == "3" { goto L }
    }

This CL switches to using a 2-level binary search---first on len(s),
then on s itself---so that string ordering comparisons are only needed
when there are 4 or more strings of the same length. (4 being the
cut-off for when using binary search is actually worthwhile.)

So the above switch instead now compiles to:

    if len(s) == 0 {
        if s == "" { goto L }
    } else if len(s) == 1 {
        if s == "1" { goto L }
        else if s == "2" { goto L }
        else if s == "3" { goto L }
    }

which is better optimized by walk and SSA. (Notably, because there are
only two distinct lengths and no more than three strings of any
particular length, this example ends up falling back to simply using
linear search.)

Test case by khr@ from CL 195138.

Fixes #33934.

Change-Id: I8eeebcaf7e26343223be5f443d6a97a0daf84f07
Reviewed-on: https://go-review.googlesource.com/c/go/+/195340
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
 2019-09-18 05:33:05 +00:00
LE Manh Cuong
ec4e8517cd cmd/compile: support more length types for slice extension optimization 
golang.org/cl/109517 optimized the compiler to avoid the allocation for make in
append(x, make([]T, y)...). This was only implemented for the case that y has type int.

This change extends the optimization to trigger for all integer types where the value
is known at compile time to fit into an int.

name             old time/op    new time/op    delta
ExtendInt-12        106ns ± 4%     106ns ± 0%      ~     (p=0.351 n=10+6)
ExtendUint64-12    1.03µs ± 5%    0.10µs ± 4%   -90.01%  (p=0.000 n=9+10)

name             old alloc/op   new alloc/op   delta
ExtendInt-12        0.00B          0.00B           ~     (all equal)
ExtendUint64-12    13.6kB ± 0%     0.0kB       -100.00%  (p=0.000 n=10+10)

name             old allocs/op  new allocs/op  delta
ExtendInt-12         0.00           0.00           ~     (all equal)
ExtendUint64-12      1.00 ± 0%      0.00       -100.00%  (p=0.000 n=10+10)

Updates #29785

Change-Id: Ief7760097c285abd591712da98c5b02bc3961fcd
Reviewed-on: https://go-review.googlesource.com/c/go/+/182559
Run-TryBot: Cuong Manh Le <cuong.manhle.vn@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
 2019-09-17 17:18:17 +00:00
Alberto Donizetti
c2facbe937 Revert "test/codegen: document -all_codegen option in README" 
This reverts CL 192101.

Reason for revert: The same paragraph was added 2 weeks ago
(look a few lines above)

Change-Id: I05efb2631d7b4966f66493f178f2a649c715a3cc
Reviewed-on: https://go-review.googlesource.com/c/go/+/195637
Reviewed-by: Cherry Zhang <cherryyz@google.com>
 2019-09-16 17:31:37 +00:00
Cherry Zhang
d9b8ffa51c test/codegen: document -all_codegen option in README 
It is useful to know about the -all_codegen option for running
codegen tests for all platforms. I was puzzling that some codegen
test was not failing on my local machine or on trybot, until I
found this option.

Change-Id: I062cf4d73f6a6c9ebc2258195779d2dab21bc36d
Reviewed-on: https://go-review.googlesource.com/c/go/+/192101
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
 2019-09-16 11:53:57 +00:00
Ruixin Bao
98aa97806b cmd/compile: add math/bits.Mul64 intrinsic on s390x 
This change adds an intrinsic for Mul64 on s390x. To achieve that,
a new assembly instruction, MLGR, is introduced in s390x/asmz.go. This assembly
instruction directly uses an existing instruction on Z and supports multiplication
of two 64 bit unsigned integer and stores the result in two separate registers.

In this case, we require the multiplcand to be stored in register R3 and
the output result (the high and low 64 bit of the product) to be stored in
R2 and R3 respectively.

A test case is also added.

Benchmark:
name      old time/op  new time/op  delta
Mul-18    11.1ns ± 0%   1.4ns ± 0%  -87.39%  (p=0.002 n=8+10)
Mul32-18  2.07ns ± 0%  2.07ns ± 0%     ~     (all equal)
Mul64-18  11.1ns ± 1%   1.4ns ± 0%  -87.42%  (p=0.000 n=10+10)

Change-Id: Ieca6ad1f61fff9a48a31d50bbd3f3c6d9e6675c1
Reviewed-on: https://go-review.googlesource.com/c/go/+/194572
Reviewed-by: Michael Munday <mike.munday@ibm.com>
Run-TryBot: Michael Munday <mike.munday@ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
 2019-09-13 09:04:48 +00:00
Michael Munday
5c5f217b63 cmd/compile: improve s390x sign/zero extension removal 
This CL gets rid of the MOVDreg and MOVDnop SSA operations on
s390x. They were originally inserted to help avoid situations
where a sign/zero extension was elided but a spill invalidated
the optimization. It's not really clear we need to do this though
(amd64 doesn't have these ops for example) so long as we are
careful when removing sign/zero extensions. Also, the MOVDreg
technique doesn't work if the register is spilled before the
MOVDreg op (I haven't seen that in practice).

Removing these ops reduces the complexity of the rules and also
allows us to unblock optimizations. For example, the compiler can
now merge the loads in binary.{Big,Little}Endian.PutUint16 which
it wasn't able to do before. This CL reduces the size of the .text
section in the go tool by about 4.7KB (0.09%).

Change-Id: Icaddae7f2e4f9b2debb6fabae845adb3f73b41db
Reviewed-on: https://go-review.googlesource.com/c/go/+/173897
Run-TryBot: Michael Munday <mike.munday@ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
 2019-09-10 13:17:24 +00:00
Martin Möhrmann
5bb59b6d16 Revert "compile: prefer an AND instead of SHR+SHL instructions" 
This reverts commit 9ec7074a94.

Reason for revert: broke s390x (copysign, abs) and arm64 (bitfield) tests.

Change-Id: I16c1b389c062e8c4aa5de079f1d46c9b25b0db52
Reviewed-on: https://go-review.googlesource.com/c/go/+/193850
Run-TryBot: Martin Möhrmann <moehrmann@google.com>
Reviewed-by: Agniva De Sarker <agniva.quicksilver@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
 2019-09-09 07:33:25 +00:00
Martin Möhrmann
9ec7074a94 compile: prefer an AND instead of SHR+SHL instructions 
On modern 64bit CPUs a SHR, SHL or AND instruction take 1 cycle to execute.
A pair of shifts that operate on the same register will take 2 cycles
and needs to wait for the input register value to be available.

Large constants used to mask the high bits of a register with an AND
instruction can not be encoded as an immediate in the AND instruction
on amd64 and therefore need to be loaded into a register with a MOV
instruction.

However that MOV instruction is not dependent on the output register and
on many CPUs does not compete with the AND or shift instructions for
execution ports.

Using a pair of shifts to mask high bits instead of an AND to mask high
bits of a register has a shorter encoding and uses one less general
purpose register but is slower due to taking one clock cycle longer
if there is no register pressure that would make the AND variant need to
generate a spill.

For example the instructions emitted for (x & 1 << 63) before this CL are:
48c1ea3f                SHRQ $0x3f, DX
48c1e23f                SHLQ $0x3f, DX

after this CL the instructions are the same as GCC and LLVM use:
48b80000000000000080    MOVQ $0x8000000000000000, AX
4821d0                  ANDQ DX, AX

Some platforms such as arm64 already have SSA optimization rules to fuse
two shift instructions back into an AND.

Removing the general rule to rewrite AND to SHR+SHL speeds up this benchmark:

var GlobalU uint

func BenchmarkAndHighBits(b *testing.B) {
	x := uint(0)
	for i := 0; i < b.N; i++ {
		x &= 1 << 63
	}
	GlobalU = x
}

amd64/darwin on Intel(R) Core(TM) i7-3520M CPU @ 2.90GHz:
name           old time/op  new time/op  delta
AndHighBits-4  0.61ns ± 6%  0.42ns ± 6%  -31.42%  (p=0.000 n=25+25):

Updates #33826
Updates #32781

Change-Id: I862d3587446410c447b9a7265196b57f85358633
Reviewed-on: https://go-review.googlesource.com/c/go/+/191780
Run-TryBot: Martin Möhrmann <moehrmann@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
 2019-09-09 06:49:17 +00:00
Alberto Donizetti
e6d2544d20 test/codegen: mention -all_codegen in the README 
For performance reasons (avoiding costly cross-compilations) CL 177577
changed the codegen test harness to only run the tests for the
machine's GOARCH by default.

This change updates the codegen README accordingly, explaining what
all.bash does run by default and how to perform the tests for all
architectures.

Fixes #33924

Change-Id: I43328d878c3e449ebfda46f7e69963a44a511d40
Reviewed-on: https://go-review.googlesource.com/c/go/+/192619
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>
 2019-09-01 15:37:13 +00:00
Brian Kessler
b003afe4fe cmd/compile: intrinsify RotateLeft32 on wasm 
wasm has 32-bit versions of all integer operations. This change
lowers RotateLeft32 to i32.rotl on wasm and intrinsifies the math/bits
call.  Benchmarking on amd64 under node.js this is ~25% faster.

node v10.15.3/amd64
name          old time/op  new time/op  delta
RotateLeft    8.37ns ± 1%  8.28ns ± 0%   -1.05%  (p=0.029 n=4+4)
RotateLeft8   11.9ns ± 1%  11.8ns ± 0%     ~     (p=0.167 n=5+5)
RotateLeft16  11.8ns ± 0%  11.8ns ± 0%     ~     (all equal)
RotateLeft32  11.9ns ± 1%   8.7ns ± 0%  -26.32%  (p=0.008 n=5+5)
RotateLeft64  8.31ns ± 1%  8.43ns ± 2%     ~     (p=0.063 n=5+5)

Updates #31265

Change-Id: I5b8e155978faeea536c4f6427ac9564d2f096a46
Reviewed-on: https://go-review.googlesource.com/c/go/+/182359
Run-TryBot: Brian Kessler <brian.m.kessler@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Richard Musiol <neelance@gmail.com>
 2019-08-31 17:03:04 +00:00
Ben Shi
1786ecd502 cmd/compile: eliminate WASM's redundant extension & wrapping 
This CL eliminates unnecessary pairs of I32WrapI64 and
I64ExtendI32U generated by the WASM backend for IF
statements. And it makes the total size of pkg/js_wasm/
decreases about 490KB.

Change-Id: I16b0abb686c4e30d5624323166ec2d0ec57dbe2d
Reviewed-on: https://go-review.googlesource.com/c/go/+/191758
Run-TryBot: Ben Shi <powerman1st@163.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Richard Musiol <neelance@gmail.com>
 2019-08-30 21:20:03 +00:00
Ben Shi
8d5197d818 cmd/compile: optimize 386's math.bits.TrailingZeros16 
This CL reverts CL 192097 and fixes the issue in CL 189277.

Change-Id: Icd271262e1f5019a8e01c91f91c12c1261eeb02b
Reviewed-on: https://go-review.googlesource.com/c/go/+/192519
Run-TryBot: Ben Shi <powerman1st@163.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
 2019-08-30 17:37:00 +00:00
Cherry Zhang
9859f6bedb test/codegen: fix ARM32 RotateLeft32 test 
The syntax of a shifted operation does not have a "$" sign for
the shift amount. Remove it.

Change-Id: I50782fe942b640076f48c2fafea4d3175be8ff99
Reviewed-on: https://go-review.googlesource.com/c/go/+/192100
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
 2019-08-28 20:42:48 +00:00
Ben Shi
3cfd003a8a cmd/compile: optimize ARM's math.bits.RotateLeft32 
This CL optimizes math.bits.RotateLeft32 to inline
"MOVW Rx@>Ry, Rd" on ARM.

The benchmark results of math/bits show some improvements.
name               old time/op  new time/op  delta
RotateLeft-4       9.42ns ± 0%  6.91ns ± 0%  -26.66%  (p=0.000 n=40+33)
RotateLeft8-4      8.79ns ± 0%  8.79ns ± 0%   -0.04%  (p=0.000 n=40+31)
RotateLeft16-4     8.79ns ± 0%  8.79ns ± 0%   -0.04%  (p=0.000 n=40+32)
RotateLeft32-4     8.16ns ± 0%  7.54ns ± 0%   -7.68%  (p=0.000 n=40+40)
RotateLeft64-4     15.7ns ± 0%  15.7ns ± 0%     ~     (all equal)

updates #31265

Change-Id: I77bc1c2c702d5323fc7cad5264a8e2d5666bf712
Reviewed-on: https://go-review.googlesource.com/c/go/+/188697
Run-TryBot: Ben Shi <powerman1st@163.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
 2019-08-28 15:41:58 +00:00
Ben Shi
c683ab8128 cmd/compile: optimize ARM's math.Abs 
This CL optimizes math.Abs to an inline ABSD instruction on ARM.

The benchmark results of src/math/ show big improvements.
name                   old time/op  new time/op  delta
Acos-4                  181ns ± 0%   182ns ± 0%   +0.30%  (p=0.000 n=40+40)
Acosh-4                 202ns ± 0%   202ns ± 0%     ~     (all equal)
Asin-4                  163ns ± 0%   163ns ± 0%     ~     (all equal)
Asinh-4                 242ns ± 0%   242ns ± 0%     ~     (all equal)
Atan-4                  120ns ± 0%   121ns ± 0%   +0.83%  (p=0.000 n=40+40)
Atanh-4                 202ns ± 0%   202ns ± 0%     ~     (all equal)
Atan2-4                 173ns ± 0%   173ns ± 0%     ~     (all equal)
Cbrt-4                 1.06µs ± 0%  1.06µs ± 0%   +0.09%  (p=0.000 n=39+37)
Ceil-4                 72.9ns ± 0%  72.8ns ± 0%     ~     (p=0.237 n=40+40)
Copysign-4             13.2ns ± 0%  13.2ns ± 0%     ~     (all equal)
Cos-4                   193ns ± 0%   183ns ± 0%   -5.18%  (p=0.000 n=40+40)
Cosh-4                  254ns ± 0%   239ns ± 0%   -5.91%  (p=0.000 n=40+40)
Erf-4                   112ns ± 0%   112ns ± 0%     ~     (all equal)
Erfc-4                  117ns ± 0%   117ns ± 0%     ~     (all equal)
Erfinv-4                127ns ± 0%   127ns ± 1%     ~     (p=0.492 n=40+40)
Erfcinv-4               128ns ± 0%   128ns ± 0%     ~     (all equal)
Exp-4                   212ns ± 0%   206ns ± 0%   -3.05%  (p=0.000 n=40+40)
ExpGo-4                 216ns ± 0%   209ns ± 0%   -3.24%  (p=0.000 n=40+40)
Expm1-4                 142ns ± 0%   142ns ± 0%     ~     (all equal)
Exp2-4                  191ns ± 0%   184ns ± 0%   -3.45%  (p=0.000 n=40+40)
Exp2Go-4                194ns ± 0%   187ns ± 0%   -3.61%  (p=0.000 n=40+40)
Abs-4                  14.4ns ± 0%   6.3ns ± 0%  -56.39%  (p=0.000 n=38+39)
Dim-4                  12.6ns ± 0%  12.6ns ± 0%     ~     (all equal)
Floor-4                49.6ns ± 0%  49.6ns ± 0%     ~     (all equal)
Max-4                  27.6ns ± 0%  27.6ns ± 0%     ~     (all equal)
Min-4                  27.0ns ± 0%  27.0ns ± 0%     ~     (all equal)
Mod-4                   349ns ± 0%   305ns ± 1%  -12.55%  (p=0.000 n=33+40)
Frexp-4                54.0ns ± 0%  47.1ns ± 0%  -12.78%  (p=0.000 n=38+38)
Gamma-4                 242ns ± 0%   234ns ± 0%   -3.16%  (p=0.000 n=36+40)
Hypot-4                84.8ns ± 0%  67.8ns ± 0%  -20.05%  (p=0.000 n=31+35)
HypotGo-4              88.5ns ± 0%  71.6ns ± 0%  -19.12%  (p=0.000 n=40+38)
Ilogb-4                45.8ns ± 0%  38.9ns ± 0%  -15.12%  (p=0.000 n=40+32)
J0-4                    821ns ± 0%   802ns ± 0%   -2.33%  (p=0.000 n=33+40)
J1-4                    816ns ± 0%   807ns ± 0%   -1.05%  (p=0.000 n=40+29)
Jn-4                   1.67µs ± 0%  1.65µs ± 0%   -1.45%  (p=0.000 n=40+39)
Ldexp-4                61.5ns ± 0%  54.6ns ± 0%  -11.27%  (p=0.000 n=40+32)
Lgamma-4                188ns ± 0%   188ns ± 0%     ~     (all equal)
Log-4                   154ns ± 0%   147ns ± 0%   -4.78%  (p=0.000 n=40+40)
Logb-4                 50.9ns ± 0%  42.7ns ± 0%  -16.11%  (p=0.000 n=34+39)
Log1p-4                 160ns ± 0%   159ns ± 0%     ~     (p=0.828 n=40+40)
Log10-4                 173ns ± 0%   166ns ± 0%   -4.05%  (p=0.000 n=40+40)
Log2-4                 65.3ns ± 0%  58.4ns ± 0%  -10.57%  (p=0.000 n=37+37)
Modf-4                 36.4ns ± 0%  36.4ns ± 0%     ~     (all equal)
Nextafter32-4          36.4ns ± 0%  36.4ns ± 0%     ~     (all equal)
Nextafter64-4          32.7ns ± 0%  32.6ns ± 0%     ~     (p=0.375 n=40+40)
PowInt-4                300ns ± 0%   277ns ± 0%   -7.78%  (p=0.000 n=40+40)
PowFrac-4               676ns ± 0%   635ns ± 0%   -6.00%  (p=0.000 n=40+35)
Pow10Pos-4             17.6ns ± 0%  17.6ns ± 0%     ~     (all equal)
Pow10Neg-4             22.0ns ± 0%  22.0ns ± 0%     ~     (all equal)
Round-4                30.1ns ± 0%  30.1ns ± 0%     ~     (all equal)
RoundToEven-4          38.9ns ± 0%  38.9ns ± 0%     ~     (all equal)
Remainder-4             291ns ± 0%   263ns ± 0%   -9.62%  (p=0.000 n=40+40)
Signbit-4              11.3ns ± 0%  11.3ns ± 0%     ~     (all equal)
Sin-4                   185ns ± 0%   185ns ± 0%     ~     (all equal)
Sincos-4                230ns ± 0%   230ns ± 0%     ~     (all equal)
Sinh-4                  253ns ± 0%   246ns ± 0%   -2.77%  (p=0.000 n=39+39)
SqrtIndirect-4         41.4ns ± 0%  41.4ns ± 0%     ~     (all equal)
SqrtLatency-4          13.8ns ± 0%  13.8ns ± 0%     ~     (all equal)
SqrtIndirectLatency-4  37.0ns ± 0%  37.0ns ± 0%     ~     (p=0.632 n=40+40)
SqrtGoLatency-4         911ns ± 0%   911ns ± 0%   +0.08%  (p=0.000 n=40+40)
SqrtPrime-4            13.2µs ± 0%  13.2µs ± 0%   +0.01%  (p=0.038 n=38+40)
Tan-4                   205ns ± 0%   205ns ± 0%     ~     (all equal)
Tanh-4                  264ns ± 0%   247ns ± 0%   -6.44%  (p=0.000 n=39+32)
Trunc-4                45.2ns ± 0%  45.2ns ± 0%     ~     (all equal)
Y0-4                    796ns ± 0%   792ns ± 0%   -0.55%  (p=0.000 n=35+40)
Y1-4                    804ns ± 0%   797ns ± 0%   -0.82%  (p=0.000 n=24+40)
Yn-4                   1.64µs ± 0%  1.62µs ± 0%   -1.27%  (p=0.000 n=40+39)
Float64bits-4          8.16ns ± 0%  8.16ns ± 0%   +0.04%  (p=0.000 n=35+40)
Float64frombits-4      10.7ns ± 0%  10.7ns ± 0%     ~     (all equal)
Float32bits-4          7.53ns ± 0%  7.53ns ± 0%     ~     (p=0.760 n=40+40)
Float32frombits-4      6.91ns ± 0%  6.91ns ± 0%   -0.04%  (p=0.002 n=32+38)
[Geo mean]              111ns        106ns        -3.98%

Change-Id: I54f4fd7f5160db020b430b556bde59cc0fdb996d
Reviewed-on: https://go-review.googlesource.com/c/go/+/188678
Run-TryBot: Ben Shi <powerman1st@163.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
 2019-08-28 15:41:28 +00:00
Bryan C. Mills
372b0eed17 Revert "cmd/compile: optimize 386's math.bits.TrailingZeros16" 
This reverts CL 189277.

Reason for revert: broke 32-bit builders.

Updates #33902

Change-Id: Ie5f180d0371a90e5057ed578c334372e5fc3a286
Reviewed-on: https://go-review.googlesource.com/c/go/+/192097
Run-TryBot: Bryan C. Mills <bcmills@google.com>
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>
 2019-08-28 12:57:59 +00:00
Agniva De Sarker
7be97af2ff cmd/compile: apply optimization for readonly globals on wasm 
Extend the optimization introduced in CL 141118 to the wasm architecture.

And for reference, the rules trigger 212 times while building std and cmd

$GOOS=js GOARCH=wasm gotip build std cmd
$grep -E "Wasm.rules:44(1|2|3|4)" rulelog | wc -l
212

Updates #26498

Change-Id: I153684a2b98589ae812b42268da08b65679e09d1
Reviewed-on: https://go-review.googlesource.com/c/go/+/185477
Run-TryBot: Agniva De Sarker <agniva.quicksilver@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Richard Musiol <neelance@gmail.com>
 2019-08-28 05:55:52 +00:00
Agniva De Sarker
8fedb2d338 cmd/compile: optimize bounded shifts on wasm 
Use the shiftIsBounded function to generate more efficient
Shift instructions.

Updates #25167

Change-Id: Id350f8462dc3a7ed3bfed0bcbea2860b8f40048a
Reviewed-on: https://go-review.googlesource.com/c/go/+/182558
Run-TryBot: Agniva De Sarker <agniva.quicksilver@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Richard Musiol <neelance@gmail.com>
 2019-08-28 04:44:21 +00:00
Ben Shi
22355d6cd2 cmd/compile: optimize 386's math.bits.TrailingZeros16 
This CL optimizes math.bits.TrailingZeros16 on 386 with
a pair of BSFL and ORL instrcutions.

The case TrailingZeros16-4 of the benchmark test in
math/bits shows big improvement.
name               old time/op  new time/op  delta
TrailingZeros16-4  1.55ns ± 1%  0.87ns ± 1%  -43.87%  (p=0.000 n=50+49)

Change-Id: Ia899975b0e46f45dcd20223b713ed632bc32740b
Reviewed-on: https://go-review.googlesource.com/c/go/+/189277
Run-TryBot: Ben Shi <powerman1st@163.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
 2019-08-28 02:29:54 +00:00
Ben Shi
731e6fc34e cmd/compile: generate Select on WASM 
This CL performs the branchelim optimization on WASM with its
select instruction. And the total size of pkg/js_wasm decreased
about 80KB by this optimization.

Change-Id: I868eb146120a1cac5c4609c8e9ddb07e4da8a1d9
Reviewed-on: https://go-review.googlesource.com/c/go/+/190957
Run-TryBot: Ben Shi <powerman1st@163.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Richard Musiol <neelance@gmail.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
 2019-08-28 02:29:25 +00:00
LE Manh Cuong
c5f142fa9f cmd/compile: optimize bitset tests 
The assembly output for x & c == c, where c is power of 2:

	MOVQ	"".set+8(SP), AX
	ANDQ	$8, AX
	CMPQ	AX, $8
	SETEQ	"".~r2+24(SP)

With optimization using bitset:

	MOVQ	"".set+8(SP), AX
	BTL	$3, AX
	SETCS	"".~r2+24(SP)

output less than 1 instruction.

However, there is no speed improvement:

name         old time/op  new time/op  delta
AllBitSet-8  0.35ns ± 0%  0.35ns ± 0%   ~     (all equal)

Fixes #31904

Change-Id: I5dca4e410bf45716ed2145e3473979ec997e35d4
Reviewed-on: https://go-review.googlesource.com/c/go/+/175957
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
 2019-08-27 18:01:16 +00:00
Keith Randall
8f296f59de Revert "Revert "cmd/compile,runtime: allocate defer records on the stack"" 
This reverts CL 180761

Reason for revert: Reinstate the stack-allocated defer CL.

There was nothing wrong with the CL proper, but stack allocation of defers exposed two other issues.

Issue #32477: Fix has been submitted as CL 181258.
Issue #32498: Possible fix is CL 181377 (not submitted yet).

Change-Id: I32b3365d5026600069291b068bbba6cb15295eb3
Reviewed-on: https://go-review.googlesource.com/c/go/+/181378
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
 2019-06-10 16:19:39 +00:00
Keith Randall
49200e3f3e Revert "cmd/compile,runtime: allocate defer records on the stack" 
This reverts commit fff4f599fe.

Reason for revert: Seems to still have issues around GC.

Fixes #32452

Change-Id: Ibe7af629f9ad6a3d5312acd7b066123f484da7f0
Reviewed-on: https://go-review.googlesource.com/c/go/+/180761
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
 2019-06-05 19:50:09 +00:00
Keith Randall
fff4f599fe cmd/compile,runtime: allocate defer records on the stack 
When a defer is executed at most once in a function body,
we can allocate the defer record for it on the stack instead
of on the heap.

This should make defers like this (which are very common) faster.

This optimization applies to 363 out of the 370 static defer sites
in the cmd/go binary.

name     old time/op  new time/op  delta
Defer-4  52.2ns ± 5%  36.2ns ± 3%  -30.70%  (p=0.000 n=10+10)

Fixes #6980
Update #14939

Change-Id: I697109dd7aeef9e97a9eeba2ef65ff53d3ee1004
Reviewed-on: https://go-review.googlesource.com/c/go/+/171758
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
 2019-06-04 17:35:20 +00:00
fanzha02
822a9f537f cmd/compile: fix the error of absorbing boolean tests into block(FGE, FGT) 
The CL 164718 mistyped the comparison flags. The rules for floating
point comparison should be GreaterThanF and GreaterEqualF. Fortunately,
the wrong optimizations were overwritten by other integer rules, so the
issue won't cause failure but just some performance impact.

The fixed CL optimizes the floating point test as follows.

source code: func foo(f float64) bool { return f > 4 || f < -4}
previous version: "FCMPD", "CSET\tGT", "CBZ"
fixed version: "FCMPD", BLE"

Add the test case.

Change-Id: Iea954fdbb8272b2d642dae0f816dc77286e6e1fa
Reviewed-on: https://go-review.googlesource.com/c/go/+/177121
Reviewed-by: Ben Shi <powerman1st@163.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Ben Shi <powerman1st@163.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
 2019-05-16 13:46:25 +00:00
Michael Munday
2c1b5130aa cmd/compile: add math/bits.{Add,Sub}64 intrinsics on s390x 
This CL adds intrinsics for the 64-bit addition and subtraction
functions in math/bits. These intrinsics use the condition code
to propagate the carry or borrow bit.

To make the carry chains more efficient I've removed the
'clobberFlags' property from most of the load and store
operations. Originally these ops did clobber flags when using
offsets that didn't fit in a signed 20-bit integer, however
that is no longer true.

As with other platforms the intrinsics are faster when executed
in a chain rather than a loop because currently we need to spill
and restore the carry bit between each loop iteration. We may
be able to reduce the need to do this on s390x (e.g. by using
compare-and-branch instructions that do not clobber flags) in the
future.

name           old time/op  new time/op  delta
Add64          1.21ns ± 2%  2.03ns ± 2%  +67.18%  (p=0.000 n=7+10)
Add64multiple  2.98ns ± 3%  1.03ns ± 0%  -65.39%  (p=0.000 n=10+9)
Sub64          1.23ns ± 4%  2.03ns ± 1%  +64.85%  (p=0.000 n=10+10)
Sub64multiple  3.73ns ± 4%  1.04ns ± 1%  -72.28%  (p=0.000 n=10+8)

Change-Id: I913bbd5e19e6b95bef52f5bc4f14d6fe40119083
Reviewed-on: https://go-review.googlesource.com/c/go/+/174303
Run-TryBot: Michael Munday <mike.munday@ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
 2019-05-03 10:41:15 +00:00
Lynn Boger
e30aa166ea test: enable more memcombine tests for ppc64le 
This enables more of the testcases in memcombine for ppc64le,
and adds more detail to some existing.

Change-Id: Ic522a1175bed682b546909c96f9ea758f8db247c
Reviewed-on: https://go-review.googlesource.com/c/go/+/174737
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
 2019-05-01 14:27:27 +00:00
Brian Kessler
4d9dd35806 cmd/compile: add signed divisibility rules 
"Division by invariant integers using multiplication" paper
by Granlund and Montgomery contains a method for directly computing
divisibility (x%c == 0 for c constant) by means of the modular inverse.
The method is further elaborated in "Hacker's Delight" by Warren Section 10-17

This general rule can compute divisibilty by one multiplication, and add
and a compare for odd divisors and an additional rotate for even divisors.

To apply the divisibility rule, we must take into account
the rules to rewrite x%c = x-((x/c)*c) and (x/c) for c constant on the first
optimization pass "opt".  This complicates the matching as we want to match
only in the cases where the result of (x/c) is not also needed.
So, we must match on the expanded form of (x/c) in the expression x == c*(x/c)
in the "late opt" pass after common subexpresion elimination.

Note, that if there is an intermediate opt pass introduced in the future we
could simplify these rules by delaying the magic division rewrite to "late opt"
and matching directly on (x/c) in the intermediate opt pass.

On amd64, the divisibility check is 30-45% faster.

name                     old time/op  new time/op  delta`
DivisiblePow2constI64-4  0.83ns ± 1%  0.82ns ± 0%     ~     (p=0.079 n=5+4)
DivisibleconstI64-4      2.68ns ± 1%  1.87ns ± 0%  -30.33%  (p=0.000 n=5+4)
DivisibleWDivconstI64-4  2.69ns ± 1%  2.71ns ± 3%     ~     (p=1.000 n=5+5)
DivisiblePow2constI32-4  1.15ns ± 1%  1.15ns ± 0%     ~     (p=0.238 n=5+4)
DivisibleconstI32-4      2.24ns ± 1%  1.20ns ± 0%  -46.48%  (p=0.016 n=5+4)
DivisibleWDivconstI32-4  2.27ns ± 1%  2.27ns ± 1%     ~     (p=0.683 n=5+5)
DivisiblePow2constI16-4  0.81ns ± 1%  0.82ns ± 1%     ~     (p=0.135 n=5+5)
DivisibleconstI16-4      2.11ns ± 2%  1.20ns ± 1%  -42.99%  (p=0.008 n=5+5)
DivisibleWDivconstI16-4  2.23ns ± 0%  2.27ns ± 2%   +1.79%  (p=0.029 n=4+4)
DivisiblePow2constI8-4   0.81ns ± 1%  0.81ns ± 1%     ~     (p=0.286 n=5+5)
DivisibleconstI8-4       2.13ns ± 3%  1.19ns ± 1%  -43.84%  (p=0.008 n=5+5)
DivisibleWDivconstI8-4   2.23ns ± 1%  2.25ns ± 1%     ~     (p=0.183 n=5+5)

Fixes #30282
Fixes #15806

Change-Id: Id20d78263a4fdfe0509229ae4dfa2fede83fc1d0
Reviewed-on: https://go-review.googlesource.com/c/go/+/173998
Run-TryBot: Brian Kessler <brian.m.kessler@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
 2019-04-30 22:02:07 +00:00
Carlos Eduardo Seo
50ad09418e cmd/compile: intrinsify math/bits.Add64 for ppc64x 
This change creates an intrinsic for Add64 for ppc64x and adds a
testcase for it.

name               old time/op  new time/op  delta
Add64-160          1.90ns ±40%  2.29ns ± 0%     ~     (p=0.119 n=5+5)
Add64multiple-160  6.69ns ± 2%  2.45ns ± 4%  -63.47%  (p=0.016 n=4+5)

Change-Id: I9abe6fb023fdf62eea3c9b46a1820f60bb0a7f97
Reviewed-on: https://go-review.googlesource.com/c/go/+/173758
Reviewed-by: Lynn Boger <laboger@linux.vnet.ibm.com>
Run-TryBot: Carlos Eduardo Seo <cseo@linux.vnet.ibm.com>
 2019-04-28 23:51:04 +00:00
Brian Kessler
a28a942768 cmd/compile: add unsigned divisibility rules 
"Division by invariant integers using multiplication" paper
by Granlund and Montgomery contains a method for directly computing
divisibility (x%c == 0 for c constant) by means of the modular inverse.
The method is further elaborated in "Hacker's Delight" by Warren Section 10-17

This general rule can compute divisibilty by one multiplication and a compare
for odd divisors and an additional rotate for even divisors.

To apply the divisibility rule, we must take into account
the rules to rewrite x%c = x-((x/c)*c) and (x/c) for c constant on the first
optimization pass "opt".  This complicates the matching as we want to match
only in the cases where the result of (x/c) is not also available.
So, we must match on the expanded form of (x/c) in the expression x == c*(x/c)
in the "late opt" pass after common subexpresion elimination.

Note, that if there is an intermediate opt pass introduced in the future we
could simplify these rules by delaying the magic division rewrite to "late opt"
and matching directly on (x/c) in the intermediate opt pass.

Additional rules to lower the generic RotateLeft* ops were also applied.

On amd64, the divisibility check is 25-50% faster.

name                     old time/op  new time/op  delta
DivconstI64-4            2.08ns ± 0%  2.08ns ± 1%     ~     (p=0.881 n=5+5)
DivisibleconstI64-4      2.67ns ± 0%  2.67ns ± 1%     ~     (p=1.000 n=5+5)
DivisibleWDivconstI64-4  2.67ns ± 0%  2.67ns ± 0%     ~     (p=0.683 n=5+5)
DivconstU64-4            2.08ns ± 1%  2.08ns ± 1%     ~     (p=1.000 n=5+5)
DivisibleconstU64-4      2.77ns ± 1%  1.55ns ± 2%  -43.90%  (p=0.008 n=5+5)
DivisibleWDivconstU64-4  2.99ns ± 1%  2.99ns ± 1%     ~     (p=1.000 n=5+5)
DivconstI32-4            1.53ns ± 2%  1.53ns ± 0%     ~     (p=1.000 n=5+5)
DivisibleconstI32-4      2.23ns ± 0%  2.25ns ± 3%     ~     (p=0.167 n=5+5)
DivisibleWDivconstI32-4  2.27ns ± 1%  2.27ns ± 1%     ~     (p=0.429 n=5+5)
DivconstU32-4            1.78ns ± 0%  1.78ns ± 1%     ~     (p=1.000 n=4+5)
DivisibleconstU32-4      2.52ns ± 2%  1.26ns ± 0%  -49.96%  (p=0.000 n=5+4)
DivisibleWDivconstU32-4  2.63ns ± 0%  2.85ns ±10%   +8.29%  (p=0.016 n=4+5)
DivconstI16-4            1.54ns ± 0%  1.54ns ± 0%     ~     (p=0.333 n=4+5)
DivisibleconstI16-4      2.10ns ± 0%  2.10ns ± 1%     ~     (p=0.571 n=4+5)
DivisibleWDivconstI16-4  2.22ns ± 0%  2.23ns ± 1%     ~     (p=0.556 n=4+5)
DivconstU16-4            1.09ns ± 0%  1.01ns ± 1%   -7.74%  (p=0.000 n=4+5)
DivisibleconstU16-4      1.83ns ± 0%  1.26ns ± 0%  -31.52%  (p=0.008 n=5+5)
DivisibleWDivconstU16-4  1.88ns ± 0%  1.89ns ± 1%     ~     (p=0.365 n=5+5)
DivconstI8-4             1.54ns ± 1%  1.54ns ± 1%     ~     (p=1.000 n=5+5)
DivisibleconstI8-4       2.10ns ± 0%  2.11ns ± 0%     ~     (p=0.238 n=5+4)
DivisibleWDivconstI8-4   2.22ns ± 0%  2.23ns ± 2%     ~     (p=0.762 n=5+5)
DivconstU8-4             0.92ns ± 1%  0.94ns ± 1%   +2.65%  (p=0.008 n=5+5)
DivisibleconstU8-4       1.66ns ± 0%  1.26ns ± 1%  -24.28%  (p=0.008 n=5+5)
DivisibleWDivconstU8-4   1.79ns ± 0%  1.80ns ± 1%     ~     (p=0.079 n=4+5)

A follow-up change will address the signed division case.

Updates #30282

Change-Id: I7e995f167179aa5c76bb10fbcbeb49c520943403
Reviewed-on: https://go-review.googlesource.com/c/go/+/168037
Run-TryBot: Brian Kessler <brian.m.kessler@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
 2019-04-27 20:46:46 +00:00
Brian Kessler
44343c777c cmd/compile: add signed divisibility by power of 2 rules 
For powers of two (c=1<<k), the divisibility check x%c == 0 can be made
just by checking the trailing zeroes via a mask x&(c-1) == 0 even for signed
integers. This avoids division fix-ups when just divisibility check is needed.

To apply this rule, we match on the fixed-up version of the division. This is
neccessary because the mod and division rewrite rules are already applied
during the initial opt pass.

The speed up on amd64 due to elimination of unneccessary fix-up code is ~55%:

name                     old time/op  new time/op  delta
DivconstI64-4            2.08ns ± 0%  2.09ns ± 1%     ~     (p=0.730 n=5+5)
DivisiblePow2constI64-4  1.78ns ± 1%  0.81ns ± 1%  -54.66%  (p=0.008 n=5+5)
DivconstU64-4            2.08ns ± 0%  2.08ns ± 0%     ~     (p=0.683 n=5+5)
DivconstI32-4            1.53ns ± 0%  1.53ns ± 1%     ~     (p=0.968 n=4+5)
DivisiblePow2constI32-4  1.79ns ± 1%  0.81ns ± 1%  -54.97%  (p=0.008 n=5+5)
DivconstU32-4            1.78ns ± 1%  1.80ns ± 2%     ~     (p=0.206 n=5+5)
DivconstI16-4            1.54ns ± 2%  1.54ns ± 0%     ~     (p=0.238 n=5+4)
DivisiblePow2constI16-4  1.78ns ± 0%  0.81ns ± 1%  -54.72%  (p=0.000 n=4+5)
DivconstU16-4            1.00ns ± 5%  1.01ns ± 1%     ~     (p=0.119 n=5+5)
DivconstI8-4             1.54ns ± 0%  1.54ns ± 2%     ~     (p=0.571 n=4+5)
DivisiblePow2constI8-4   1.78ns ± 0%  0.82ns ± 8%  -53.71%  (p=0.008 n=5+5)
DivconstU8-4             0.93ns ± 1%  0.93ns ± 1%     ~     (p=0.643 n=5+5)

A follow-up CL will address the general case of x%c == 0 for signed integers.

Updates #15806

Change-Id: Iabadbbe369b6e0998c8ce85d038ebc236142e42a
Reviewed-on: https://go-review.googlesource.com/c/go/+/173557
Run-TryBot: Brian Kessler <brian.m.kessler@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
 2019-04-25 03:00:32 +00:00
Keith Randall
17615969b6 Revert "cmd/compile: add signed divisibility by power of 2 rules" 
This reverts CL 168038 (git 68819fb6d2)

Reason for revert: Doesn't work on 32 bit archs.

Change-Id: Idec9098060dc65bc2f774c5383f0477f8eb63a3d
Reviewed-on: https://go-review.googlesource.com/c/go/+/173442
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
 2019-04-23 21:23:18 +00:00
Brian Kessler
68819fb6d2 cmd/compile: add signed divisibility by power of 2 rules 
For powers of two (c=1<<k), the divisibility check x%c == 0 can be made
just by checking the trailing zeroes via a mask x&(c-1)==0 even for signed
integers.  This avoids division fixups when just divisibility check is needed.

To apply this rule the generic divisibility rule for  A%B = A-(A/B*B) is disabled
on the "opt" pass, but this does not affect generated code as this rule is applied
later.

The speed up on amd64 due to elimination of unneccessary fixup code is ~55%:

name                     old time/op  new time/op  delta
DivconstI64-4            2.08ns ± 0%  2.07ns ± 0%     ~     (p=0.079 n=5+5)
DivisiblePow2constI64-4  1.78ns ± 1%  0.81ns ± 1%  -54.55%  (p=0.008 n=5+5)
DivconstU64-4            2.08ns ± 0%  2.08ns ± 0%     ~     (p=1.000 n=5+5)
DivconstI32-4            1.53ns ± 0%  1.53ns ± 0%     ~     (all equal)
DivisiblePow2constI32-4  1.79ns ± 1%  0.81ns ± 4%  -54.75%  (p=0.008 n=5+5)
DivconstU32-4            1.78ns ± 1%  1.78ns ± 1%     ~     (p=1.000 n=5+5)
DivconstI16-4            1.54ns ± 2%  1.53ns ± 0%     ~     (p=0.333 n=5+4)
DivisiblePow2constI16-4  1.78ns ± 0%  0.79ns ± 1%  -55.39%  (p=0.000 n=4+5)
DivconstU16-4            1.00ns ± 5%  0.99ns ± 1%     ~     (p=0.730 n=5+5)
DivconstI8-4             1.54ns ± 0%  1.53ns ± 0%     ~     (p=0.714 n=4+5)
DivisiblePow2constI8-4   1.78ns ± 0%  0.80ns ± 0%  -55.06%  (p=0.000 n=5+4)
DivconstU8-4             0.93ns ± 1%  0.95ns ± 1%   +1.72%  (p=0.024 n=5+5)

A follow-up CL will address the general case of x%c == 0 for signed integers.

Updates #15806

Change-Id: I0d284863774b1bc8c4ce87443bbaec6103e14ef4
Reviewed-on: https://go-review.googlesource.com/c/go/+/168038
Reviewed-by: Keith Randall <khr@golang.org>
 2019-04-23 20:35:54 +00:00
Keith Randall
fd788a86b6 cmd/compile: always mark atColumn1 results as statements 
In 31618, we end up comparing the is-stmt-ness of positions
to repurpose real instructions as inline marks. If the is-stmt-ness
doesn't match, we end up not being able to remove the inline mark.

Always use statement-full positions to do the matching, so we
always find a match if there is one.

Also always use positions that are statements for inline marks.

Fixes #31618

Change-Id: Idaf39bdb32fa45238d5cd52973cadf4504f947d5
Reviewed-on: https://go-review.googlesource.com/c/go/+/173324
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: David Chase <drchase@google.com>
 2019-04-23 17:39:11 +00:00
erifan01
f8f265b9cf cmd/compile: intrinsify math/bits.Sub64 for arm64 
This CL instrinsifies Sub64 with arm64 instruction sequence NEGS, SBCS,
NGC and NEG, and optimzes the case of borrowing chains.

Benchmarks:
name              old time/op       new time/op       delta
Sub-64            2.500000ns +- 0%  2.048000ns +- 1%  -18.08%  (p=0.000 n=10+10)
Sub32-64          2.500000ns +- 0%  2.500000ns +- 0%     ~     (all equal)
Sub64-64          2.500000ns +- 0%  2.080000ns +- 0%  -16.80%  (p=0.000 n=10+7)
Sub64multiple-64  7.090000ns +- 0%  2.090000ns +- 0%  -70.52%  (p=0.000 n=10+10)

Change-Id: I3d2664e009a9635e13b55d2c4567c7b34c2c0655
Reviewed-on: https://go-review.googlesource.com/c/go/+/159018
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
 2019-04-22 14:40:20 +00:00
Josh Bleecher Snyder
68d4b1265e cmd/compile: reduce bits.Div64(0, lo, y) to 64 bit division 
With this change, these two functions generate identical code:

func f(x uint64) (uint64, uint64) {
	return bits.Div64(0, x, 5)
}

func g(x uint64) (uint64, uint64) {
	return x / 5, x % 5
}

Updates #31582

Change-Id: Ia96c2e67f8af5dd985823afee5f155608c04a4b6
Reviewed-on: https://go-review.googlesource.com/c/go/+/173197
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
 2019-04-20 19:34:03 +00:00
Keith Randall
48ef01051a cmd/compile: handle new panicindex/slice names in optimizations 
These new calls should not prevent NOSPLIT promotion, like the old ones.
These new calls should not prevent racefuncenter/exit removal.

(The latter was already true, as the new calls are not yet lowered
to StaticCalls at the point where racefuncenter/exit removal is done.)

Add tests to make sure we don't regress (again).

Fixes #31219

Change-Id: I3fb6b17cdd32c425829f1e2498defa813a5a9ace
Reviewed-on: https://go-review.googlesource.com/c/go/+/170639
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ilya Tocar <ilya.tocar@intel.com>
 2019-04-03 21:24:17 +00:00
erifan01
d0cbf9bf53 cmd/compile: follow up intrinsifying math/bits.Add64 for arm64 
This CL deals with the additional comments of CL 159017.

Change-Id: I4ad3c60c834646d58dc0c544c741b92bfe83fb8b
Reviewed-on: https://go-review.googlesource.com/c/go/+/168857
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
 2019-03-22 15:09:47 +00:00
Carlos Eduardo Seo
3023d7da49 cmd/compile/internal, cmd/internal/obj/ppc64: generate new count trailing zeros instructions on POWER9 
This change adds new POWER9 instructions for counting trailing zeros (CNTTZW/CNTTZD)
to the assembler and generates them in SSA when GOPPC64=power9.

name                 old time/op  new time/op  delta
TrailingZeros-160    1.59ns ±20%  1.45ns ±10%  -8.81%  (p=0.000 n=14+13)
TrailingZeros8-160   1.55ns ±23%  1.62ns ±44%    ~     (p=0.593 n=13+15)
TrailingZeros16-160  1.78ns ±23%  1.62ns ±38%  -9.31%  (p=0.003 n=14+14)
TrailingZeros32-160  1.64ns ±10%  1.49ns ± 9%  -9.15%  (p=0.000 n=13+14)
TrailingZeros64-160  1.53ns ± 6%  1.45ns ± 5%  -5.38%  (p=0.000 n=15+13)

Change-Id: I365e6ff79f3ce4d8ebe089a6a86b1771853eb596
Reviewed-on: https://go-review.googlesource.com/c/go/+/167517
Reviewed-by: Lynn Boger <laboger@linux.vnet.ibm.com>
 2019-03-20 20:27:00 +00:00
erifan01
5714c91b53 cmd/compile: intrinsify math/bits.Add64 for arm64 
This CL instrinsifies Add64 with arm64 instruction sequence ADDS, ADCS
and ADC, and optimzes the case of carry chains.The CL also changes the
test code so that the intrinsic implementation can be tested.

Benchmarks:
name               old time/op       new time/op       delta
Add-224            2.500000ns +- 0%  2.090000ns +- 4%  -16.40%  (p=0.000 n=9+10)
Add32-224          2.500000ns +- 0%  2.500000ns +- 0%     ~     (all equal)
Add64-224          2.500000ns +- 0%  1.577778ns +- 2%  -36.89%  (p=0.000 n=10+9)
Add64multiple-224  6.000000ns +- 0%  2.000000ns +- 0%  -66.67%  (p=0.000 n=10+10)

Change-Id: I6ee91c9a85c16cc72ade5fd94868c579f16c7615
Reviewed-on: https://go-review.googlesource.com/c/go/+/159017
Run-TryBot: Ben Shi <powerman1st@163.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
 2019-03-20 05:39:49 +00:00
Josh Bleecher Snyder
250b96a7bf cmd/compile: slightly optimize adding 128 
'SUBQ $-0x80, r' is shorter to encode than 'ADDQ $0x80, r',
and functionally equivalent. Use it instead.

Shaves off a few bytes here and there:

file    before    after     Δ       %       
compile 25935856  25927664  -8192   -0.032% 
nm      4251840   4247744   -4096   -0.096% 

Change-Id: Ia9e02ea38cbded6a52a613b92e3a914f878d931e
Reviewed-on: https://go-review.googlesource.com/c/go/+/168344
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
 2019-03-19 19:44:52 +00:00
Keith Randall
2c423f063b cmd/compile,runtime: provide index information on bounds check failure 
A few examples (for accessing a slice of length 3):

   s[-1]    runtime error: index out of range [-1]
   s[3]     runtime error: index out of range [3] with length 3
   s[-1:0]  runtime error: slice bounds out of range [-1:]
   s[3:0]   runtime error: slice bounds out of range [3:0]
   s[3:-1]  runtime error: slice bounds out of range [:-1]
   s[3:4]   runtime error: slice bounds out of range [:4] with capacity 3
   s[0:3:4] runtime error: slice bounds out of range [::4] with capacity 3

Note that in cases where there are multiple things wrong with the
indexes (e.g. s[3:-1]), we report one of those errors kind of
arbitrarily, currently the rightmost one.

An exhaustive set of examples is in issue30116[u].out in the CL.

The message text has the same prefix as the old message text. That
leads to slightly awkward phrasing but hopefully minimizes the chance
that code depending on the error text will break.

Increases the size of the go binary by 0.5% (amd64). The panic functions
take arguments in registers in order to keep the size of the compiled code
as small as possible.

Fixes #30116

Change-Id: Idb99a827b7888822ca34c240eca87b7e44a04fdd
Reviewed-on: https://go-review.googlesource.com/c/go/+/161477
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
 2019-03-18 17:33:38 +00:00
Tobias Klauser
156c830bea cmd/compile: eliminate unnecessary type conversions in TrailingZeros(16|8) for arm 
This follows CL 156999 which did the same for arm64.

name               old time/op  new time/op  delta
TrailingZeros-4    7.30ns ± 1%  7.30ns ± 0%     ~     (p=0.413 n=9+9)
TrailingZeros8-4   8.32ns ± 0%  7.17ns ± 0%  -13.77%  (p=0.000 n=10+9)
TrailingZeros16-4  8.30ns ± 0%  7.18ns ± 0%  -13.50%  (p=0.000 n=9+10)
TrailingZeros32-4  6.46ns ± 1%  6.47ns ± 1%     ~     (p=0.325 n=10+10)
TrailingZeros64-4  16.3ns ± 0%  16.2ns ± 0%   -0.61%  (p=0.000 n=7+10)

Change-Id: I7e9e1abf7e30d811aa474d272b2824ec7cbbaa98
Reviewed-on: https://go-review.googlesource.com/c/go/+/167797
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
 2019-03-15 18:37:22 +00:00
Richard Musiol
5ee1b84959 math, math/bits: add intrinsics for wasm 
This commit adds compiler intrinsics for the packages math and
math/bits on the wasm architecture for better performance.

benchmark                        old ns/op     new ns/op     delta
BenchmarkCeil                    8.31          3.21          -61.37%
BenchmarkCopysign                5.24          3.88          -25.95%
BenchmarkAbs                     5.42          3.34          -38.38%
BenchmarkFloor                   8.29          3.18          -61.64%
BenchmarkRoundToEven             9.76          3.26          -66.60%
BenchmarkSqrtLatency             8.13          4.88          -39.98%
BenchmarkSqrtPrime               5246          3535          -32.62%
BenchmarkTrunc                   8.29          3.15          -62.00%
BenchmarkLeadingZeros            13.0          4.23          -67.46%
BenchmarkLeadingZeros8           4.65          4.42          -4.95%
BenchmarkLeadingZeros16          7.60          4.38          -42.37%
BenchmarkLeadingZeros32          10.7          4.48          -58.13%
BenchmarkLeadingZeros64          12.9          4.31          -66.59%
BenchmarkTrailingZeros           6.52          4.04          -38.04%
BenchmarkTrailingZeros8          4.57          4.14          -9.41%
BenchmarkTrailingZeros16         6.69          4.16          -37.82%
BenchmarkTrailingZeros32         6.97          4.23          -39.31%
BenchmarkTrailingZeros64         6.59          4.00          -39.30%
BenchmarkOnesCount               7.93          3.30          -58.39%
BenchmarkOnesCount8              3.56          3.19          -10.39%
BenchmarkOnesCount16             4.85          3.19          -34.23%
BenchmarkOnesCount32             7.27          3.19          -56.12%
BenchmarkOnesCount64             8.08          3.28          -59.41%
BenchmarkRotateLeft              4.88          3.80          -22.13%
BenchmarkRotateLeft64            5.03          3.63          -27.83%

Change-Id: Ic1e0c2984878be8defb6eb7eb6ee63765c793222
Reviewed-on: https://go-review.googlesource.com/c/go/+/165177
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
 2019-03-14 19:46:19 +00:00
Josh Bleecher Snyder
61945fc502 cmd/compile: don't generate panicshift for masked int shifts 
We know that a & 31 is non-negative for all a, signed or not.
We can avoid checking that and needing to write out an
unreachable call to panicshift.

Change-Id: I32f32fb2c950d2b2b35ac5c0e99b7b2dbd47f917
Reviewed-on: https://go-review.googlesource.com/c/go/+/167499
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Keith Randall <khr@golang.org>
 2019-03-14 00:03:29 +00:00
Josh Bleecher Snyder
870cfe6484 test/codegen: gofmt 
Change-Id: I33f5b5051e5f75aa264ec656926223c5a3c09c1b
Reviewed-on: https://go-review.googlesource.com/c/go/+/167498
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Matt Layher <mdlayher@gmail.com>
 2019-03-13 21:44:45 +00:00
Keith Randall
486ca37b14 test: fix memcombine tests 
Two tests (load_le_byte8_uint64_inv and load_be_byte8_uint64)
pass but the generated code isn't actually correct.

The test regexp provides a false negative, as it matches the
MOVQ (SP), BP instruction in the epilogue.

Combined loads never worked for these cases - the test was added in error
as part of a batch and not noticed because of the above false match.

Normalize the amd64/386 tests to always negative match on narrower
loads and OR.

Change-Id: I256861924774d39db0e65723866c81df5ab5076f
Reviewed-on: https://go-review.googlesource.com/c/go/+/166837
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
 2019-03-11 19:18:03 +00:00
fanzha02
6efd51c6b7 cmd/compile: change the condition flags of floating-point comparisons in arm64 backend 
Current compiler reverses operands to work around NaN in
"less than" and "less equal than" comparisons. But if we
want to use "FCMPD/FCMPS $(0.0), Fn" to do some optimization,
the workaround way does not work. Because assembler does
not support instruction "FCMPD/FCMPS Fn, $(0.0)".

This CL sets condition flags for floating-point comparisons
to resolve this problem.

Change-Id: Ia48076a1da95da64596d6e68304018cb301ebe33
Reviewed-on: https://go-review.googlesource.com/c/go/+/164718
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
 2019-03-07 21:23:52 +00:00
erifan01
4e2b0dda8c cmd/compile: eliminate unnecessary type conversions in TrailingZeros(16|8) for arm64 
This CL eliminates unnecessary type conversion operations: OpZeroExt16to64 and OpZeroExt8to64.
If the input argrument is a nonzero value, then ORconst operation can also be eliminated.

Benchmarks:

name               old time/op  new time/op  delta
TrailingZeros-8    2.75ns ± 0%  2.75ns ± 0%     ~     (all equal)
TrailingZeros8-8   3.49ns ± 1%  2.93ns ± 0%  -16.00%  (p=0.000 n=10+10)
TrailingZeros16-8  3.49ns ± 1%  2.93ns ± 0%  -16.05%  (p=0.000 n=9+10)
TrailingZeros32-8  2.67ns ± 1%  2.68ns ± 1%     ~     (p=0.468 n=10+10)
TrailingZeros64-8  2.67ns ± 1%  2.65ns ± 0%   -0.62%  (p=0.022 n=10+9)

code:

func f16(x uint) { z = bits.TrailingZeros16(uint16(x)) }

Before:

"".f16 STEXT size=48 args=0x8 locals=0x0 leaf
        0x0000 00000 (test.go:7)        TEXT    "".f16(SB), LEAF|NOFRAME|ABIInternal, $0-8
        0x0000 00000 (test.go:7)        FUNCDATA        ZR, gclocals·33cdeccccebe80329f1fdbee7f5874cb(SB)
        0x0000 00000 (test.go:7)        FUNCDATA        $1, gclocals·33cdeccccebe80329f1fdbee7f5874cb(SB)
        0x0000 00000 (test.go:7)        FUNCDATA        $3, gclocals·33cdeccccebe80329f1fdbee7f5874cb(SB)
        0x0000 00000 (test.go:7)        PCDATA  $2, ZR
        0x0000 00000 (test.go:7)        PCDATA  ZR, ZR
        0x0000 00000 (test.go:7)        MOVD    "".x(FP), R0
        0x0004 00004 (test.go:7)        MOVHU   R0, R0
        0x0008 00008 (test.go:7)        ORR     $65536, R0, R0
        0x000c 00012 (test.go:7)        RBIT    R0, R0
        0x0010 00016 (test.go:7)        CLZ     R0, R0
        0x0014 00020 (test.go:7)        MOVD    R0, "".z(SB)
        0x0020 00032 (test.go:7)        RET     (R30)

This line of code is unnecessary:
        0x0004 00004 (test.go:7)        MOVHU   R0, R0

After:

"".f16 STEXT size=32 args=0x8 locals=0x0 leaf
        0x0000 00000 (test.go:7)        TEXT    "".f16(SB), LEAF|NOFRAME|ABIInternal, $0-8
        0x0000 00000 (test.go:7)        FUNCDATA        ZR, gclocals·33cdeccccebe80329f1fdbee7f5874cb(SB)
        0x0000 00000 (test.go:7)        FUNCDATA        $1, gclocals·33cdeccccebe80329f1fdbee7f5874cb(SB)
        0x0000 00000 (test.go:7)        FUNCDATA        $3, gclocals·33cdeccccebe80329f1fdbee7f5874cb(SB)
        0x0000 00000 (test.go:7)        PCDATA  $2, ZR
        0x0000 00000 (test.go:7)        PCDATA  ZR, ZR
        0x0000 00000 (test.go:7)        MOVD    "".x(FP), R0
        0x0004 00004 (test.go:7)        ORR     $65536, R0, R0
        0x0008 00008 (test.go:7)        RBITW   R0, R0
        0x000c 00012 (test.go:7)        CLZW    R0, R0
        0x0010 00016 (test.go:7)        MOVD    R0, "".z(SB)
        0x001c 00028 (test.go:7)        RET     (R30)

The situation of TrailingZeros8 is similar to TrailingZeros16.

Change-Id: I473bdca06be8460a0be87abbae6fe640017e4c9d
Reviewed-on: https://go-review.googlesource.com/c/go/+/156999
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
 2019-03-07 14:24:56 +00:00
erifan01
fee84cc905 cmd/compile: add an optimization rule for math/bits.ReverseBytes16 on arm 
This CL adds two rules to turn patterns like ((x<<8) | (x>>8)) (the type of
x is uint16, "|" can also be "+" or "^") to a REV16 instruction on arm v6+.
This optimization rule can be used for math/bits.ReverseBytes16.

Benchmarks on arm v6:
name               old time/op  new time/op  delta
ReverseBytes-32    2.86ns ± 0%  2.86ns ± 0%   ~     (all equal)
ReverseBytes16-32  2.86ns ± 0%  2.86ns ± 0%   ~     (all equal)
ReverseBytes32-32  1.29ns ± 0%  1.29ns ± 0%   ~     (all equal)
ReverseBytes64-32  1.43ns ± 0%  1.43ns ± 0%   ~     (all equal)

Change-Id: I819e633c9a9d308f8e476fb0c82d73fb73dd019f
Reviewed-on: https://go-review.googlesource.com/c/go/+/159019
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
 2019-03-07 13:37:54 +00:00
erifan01
159b2de442 cmd/compile: optimize math/bits.Div32 for arm64 
Benchmark:
name     old time/op  new time/op  delta
Div-8    22.0ns ± 0%  22.0ns ± 0%     ~     (all equal)
Div32-8  6.51ns ± 0%  3.00ns ± 0%  -53.90%  (p=0.000 n=10+8)
Div64-8  22.5ns ± 0%  22.5ns ± 0%     ~     (all equal)

Code:
func div32(hi, lo, y uint32) (q, r uint32) {return bits.Div32(hi, lo, y)}

Before:
        0x0020 00032 (test.go:24)       MOVWU   "".y+8(FP), R0
        0x0024 00036 ($GOROOT/src/math/bits/bits.go:472)        CBZW    R0, 132
        0x0028 00040 ($GOROOT/src/math/bits/bits.go:472)        MOVWU   "".hi(FP), R1
        0x002c 00044 ($GOROOT/src/math/bits/bits.go:472)        CMPW    R1, R0
        0x0030 00048 ($GOROOT/src/math/bits/bits.go:472)        BLS     96
        0x0034 00052 ($GOROOT/src/math/bits/bits.go:475)        MOVWU   "".lo+4(FP), R2
        0x0038 00056 ($GOROOT/src/math/bits/bits.go:475)        ORR     R1<<32, R2, R1
        0x003c 00060 ($GOROOT/src/math/bits/bits.go:476)        CBZ     R0, 140
        0x0040 00064 ($GOROOT/src/math/bits/bits.go:476)        UDIV    R0, R1, R2
        0x0044 00068 (test.go:24)       MOVW    R2, "".q+16(FP)
        0x0048 00072 ($GOROOT/src/math/bits/bits.go:476)        UREM    R0, R1, R0
        0x0050 00080 (test.go:24)       MOVW    R0, "".r+20(FP)
        0x0054 00084 (test.go:24)       MOVD    -8(RSP), R29
        0x0058 00088 (test.go:24)       MOVD.P  32(RSP), R30
        0x005c 00092 (test.go:24)       RET     (R30)

After:
        0x001c 00028 (test.go:24)       MOVWU   "".y+8(FP), R0
        0x0020 00032 (test.go:24)       CBZW    R0, 92
        0x0024 00036 (test.go:24)       MOVWU   "".hi(FP), R1
        0x0028 00040 (test.go:24)       CMPW    R0, R1
        0x002c 00044 (test.go:24)       BHS     84
        0x0030 00048 (test.go:24)       MOVWU   "".lo+4(FP), R2
        0x0034 00052 (test.go:24)       ORR     R1<<32, R2, R4
        0x0038 00056 (test.go:24)       UDIV    R0, R4, R3
        0x003c 00060 (test.go:24)       MSUB    R3, R4, R0, R4
        0x0040 00064 (test.go:24)       MOVW    R3, "".q+16(FP)
        0x0044 00068 (test.go:24)       MOVW    R4, "".r+20(FP)
        0x0048 00072 (test.go:24)       MOVD    -8(RSP), R29
        0x004c 00076 (test.go:24)       MOVD.P  16(RSP), R30
        0x0050 00080 (test.go:24)       RET     (R30)

UREM instruction in the previous assembly code will be converted to UDIV and MSUB instructions
on arm64. However the UDIV instruction in UREM is unnecessary, because it's a duplicate of the
previous UDIV. This CL adds a rule to have this extra UDIV instruction removed by CSE.

Change-Id: Ie2508784320020b2de022806d09f75a7871bb3d7
Reviewed-on: https://go-review.googlesource.com/c/159577
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Bryan C. Mills <bcmills@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
 2019-03-03 20:20:10 +00:00
erifan01
192b675f17 cmd/compile: add an optimaztion rule for math/bits.ReverseBytes16 on arm64 
On amd64 ReverseBytes16 is lowered to a rotate instruction. However arm64 doesn't
have 16-bit rotate instruction, but has a REV16W instruction which can be used
for ReverseBytes16. This CL adds a rule to turn the patterns like (x<<8) | (x>>8)
(the type of x is uint16, and "|" can also be "^" or "+") to a REV16W instruction.

Code:
func reverseBytes16(i uint16) uint16 { return bits.ReverseBytes16(i) }

Before:
        0x0004 00004 (test.go:6)        MOVHU   "".i(FP), R0
        0x0008 00008 ($GOROOT/src/math/bits/bits.go:262)        UBFX    $8, R0, $8, R1
        0x000c 00012 ($GOROOT/src/math/bits/bits.go:262)        ORR     R0<<8, R1, R0
        0x0010 00016 (test.go:6)        MOVH    R0, "".~r1+8(FP)
        0x0014 00020 (test.go:6)        RET     (R30)

After:
        0x0000 00000 (test.go:6)        MOVHU   "".i(FP), R0
        0x0004 00004 (test.go:6)        REV16W  R0, R0
        0x0008 00008 (test.go:6)        MOVH    R0, "".~r1+8(FP)
        0x000c 00012 (test.go:6)        RET     (R30)

Benchmarks:
name                old time/op       new time/op       delta
ReverseBytes-224    1.000000ns +- 0%  1.000000ns +- 0%     ~     (all equal)
ReverseBytes16-224  1.500000ns +- 0%  1.000000ns +- 0%  -33.33%  (p=0.000 n=9+10)
ReverseBytes32-224  1.000000ns +- 0%  1.000000ns +- 0%     ~     (all equal)
ReverseBytes64-224  1.000000ns +- 0%  1.000000ns +- 0%     ~     (all equal)

Change-Id: I87cd41b2d8e549bf39c601f185d5775bd42d739c
Reviewed-on: https://go-review.googlesource.com/c/157757
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
 2019-03-01 15:42:19 +00:00
erifan01
dd91269b7c cmd/compile: optimize math/bits Len32 intrinsic on arm64 
Arm64 has a 32-bit CLZ instruction CLZW, which can be used for intrinsic Len32.
Function LeadingZeros32 calls Len32, with this change, the assembly code of
LeadingZeros32 becomes more concise.

Go code:

func f32(x uint32) { z = bits.LeadingZeros32(x) }

Before:

"".f32 STEXT size=32 args=0x8 locals=0x0 leaf
        0x0000 00000 (test.go:7)        TEXT    "".f32(SB), LEAF|NOFRAME|ABIInternal, $0-8
        0x0004 00004 (test.go:7)        MOVWU   "".x(FP), R0
        0x0008 00008 ($GOROOT/src/math/bits/bits.go:30) CLZ     R0, R0
        0x000c 00012 ($GOROOT/src/math/bits/bits.go:30) SUB     $32, R0, R0
        0x0010 00016 (test.go:7)        MOVD    R0, "".z(SB)
        0x001c 00028 (test.go:7)        RET     (R30)

After:

"".f32 STEXT size=32 args=0x8 locals=0x0 leaf
        0x0000 00000 (test.go:7)        TEXT    "".f32(SB), LEAF|NOFRAME|ABIInternal, $0-8
        0x0004 00004 (test.go:7)        MOVWU   "".x(FP), R0
        0x0008 00008 ($GOROOT/src/math/bits/bits.go:30) CLZW    R0, R0
        0x000c 00012 (test.go:7)        MOVD    R0, "".z(SB)
        0x0018 00024 (test.go:7)        RET     (R30)

Benchmarks:
name              old time/op  new time/op  delta
LeadingZeros-8    2.53ns ± 0%  2.55ns ± 0%   +0.67%  (p=0.000 n=10+10)
LeadingZeros8-8   3.56ns ± 0%  3.56ns ± 0%     ~     (all equal)
LeadingZeros16-8  3.55ns ± 0%  3.56ns ± 0%     ~     (p=0.465 n=10+10)
LeadingZeros32-8  3.55ns ± 0%  2.96ns ± 0%  -16.71%  (p=0.000 n=10+7)
LeadingZeros64-8  2.53ns ± 0%  2.54ns ± 0%     ~     (p=0.059 n=8+10)

Change-Id: Ie5666bb82909e341060e02ffd4e86c0e5d67e90a
Reviewed-on: https://go-review.googlesource.com/c/157000
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
 2019-02-27 16:09:33 +00:00
Iskander Sharipov
c1050a8e54 cmd/compile: don't generate newobject call for 0-sized types 
Emit &runtime.zerobase instead of a call to newobject for
allocations of zero sized objects in walk.go.

Fixes #29446

Change-Id: I11b67981d55009726a17c2e582c12ce0c258682e
Reviewed-on: https://go-review.googlesource.com/c/155840
Run-TryBot: Iskander Sharipov <quasilyte@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Keith Randall <khr@golang.org>
 2019-02-26 23:08:15 +00:00
Keith Randall
933e34ac99 cmd/compile: treat slice pointers as non-nil 
var a []int = ...
p := &a[0]
_ = *p

We don't need to nil check on the 3rd line. If the bounds check on the 2nd
line passes, we know p is non-nil.

We rely on the fact that any cap>0 slice has a non-nil pointer as its
pointer to the backing array. This is true for all safely-constructed slices,
and I don't see any reason why someone would violate this rule using unsafe.

R=go1.13

Fixes #30366

Change-Id: I3ed764fcb72cfe1fbf963d8c1a82e24e3b6dead7
Reviewed-on: https://go-review.googlesource.com/c/163740
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
 2019-02-26 20:44:52 +00:00
Keith Randall
c5414457c6 cmd/compile: pad zero-sized stack variables 
If someone takes a pointer to a zero-sized stack variable, it can
be incorrectly interpreted as a pointer to the next object in the
stack frame. To avoid this, add some padding after zero-sized variables.

We only need to pad if the next variable in memory (which is the
previous variable in the order in which we allocate variables to the
stack frame) has pointers. If the next variable has no pointers, it
won't hurt to have a pointer to it.

Because we allocate all pointer-containing variables before all
non-pointer-containing variables, we should only have to pad once per
frame.

Fixes #24993

Change-Id: Ife561cdfdf964fdbf69af03ae6ba97d004e6193c
Reviewed-on: https://go-review.googlesource.com/c/155698
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
 2018-12-22 01:16:00 +00:00
Ben Shi
c042fedbc8 test/codegen: add arithmetic tests for 386/amd64/arm/arm64 
This CL adds several test cases of arithmetic operations for
386/amd64/arm/arm64.

Change-Id: I362687c06249f31091458a1d8c45fc4d006b616a
Reviewed-on: https://go-review.googlesource.com/c/151897
Run-TryBot: Ben Shi <powerman1st@163.com>
Reviewed-by: Keith Randall <khr@golang.org>
 2018-12-01 05:17:44 +00:00
Keith Randall
0b79dde112 cmd/compile: don't use CMOV ops to compute load addresses 
We want to issue loads as soon as possible, especially when they
are going to miss in the cache. Using a conditional move (CMOV) here:

i := ...
if cond {
   i++
}
... = a[i]

means that we have to wait for cond to be computed before the load
is issued. Without a CMOV, if the branch is predicted correctly the
load can be issued in parallel with computing cond.
Even if the branch is predicted incorrectly, maybe the speculative
load is close to the real load, and we get a prefetch for free.
In the worst case, when the prediction is wrong and the address is
way off, we only lose by the time difference between the CMOV
latency (~2 cycles) and the mispredict restart latency (~15 cycles).

We only squash CMOVs that affect load addresses. Results of CMOVs
that are used for other things (store addresses, store values) we
use as before.

Fixes #26306

Change-Id: I82ca14b664bf05e1d45e58de8c4d9c775a127ca1
Reviewed-on: https://go-review.googlesource.com/c/145717
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
 2018-11-27 17:22:37 +00:00
Brian Kessler
319787a528 cmd/compile: intrinsify math/bits.Div on amd64 
Note that the intrinsic implementation panics separately for overflow and
divide by zero, which matches the behavior of the pure go implementation.
There is a modest performance improvement after intrinsic implementation.

name     old time/op  new time/op  delta
Div-4    53.0ns ± 1%  47.0ns ± 0%  -11.28%  (p=0.008 n=5+5)
Div32-4  18.4ns ± 0%  18.5ns ± 1%     ~     (p=0.444 n=5+5)
Div64-4  53.3ns ± 0%  47.5ns ± 4%  -10.77%  (p=0.008 n=5+5)

Updates #28273

Change-Id: Ic1688ecc0964acace2e91bf44ef16f5fb6b6bc82
Reviewed-on: https://go-review.googlesource.com/c/144378
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
 2018-11-27 05:04:25 +00:00
Martin Möhrmann
75798e8ada runtime: make processor capability variable naming platform specific 
The current support_XXX variables are specific for the
amd64 and 386 platforms.

Prefix processor capability variables by architecture to have a
consistent naming scheme and avoid reuse of the existing
variables for new platforms.

This also aligns naming of runtime variables closer with internal/cpu
processor capability variable names.

Change-Id: I3eabb29a03874678851376185d3a62e73c1aff1d
Reviewed-on: https://go-review.googlesource.com/c/91435
Run-TryBot: Martin Möhrmann <martisch@uos.de>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
 2018-11-14 20:30:31 +00:00
Lynn Boger
4ae49b5921 cmd/compile: use ANDCC, ORCC, XORCC to avoid CMP on ppc64x 
This change makes use of the cc versions of the AND, OR, XOR
instructions, omitting the need for a CMP instruction.

In many test programs and in the go binary, this reduces the
size of 20-30 functions by at least 1 instruction, many in
runtime.

Testcase added to test/codegen/comparisons.go

Change-Id: I6cc1ca8b80b065d7390749c625bc9784b0039adb
Reviewed-on: https://go-review.googlesource.com/c/143059
Reviewed-by: Carlos Eduardo Seo <cseo@linux.vnet.ibm.com>
Reviewed-by: Michael Munday <mike.munday@ibm.com>
Run-TryBot: Lynn Boger <laboger@linux.vnet.ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
 2018-11-09 19:40:52 +00:00
Keith Randall
0ad332d80c cmd/compile: implement some moves using non-overlapping reads&writes 
For moves >8,<16 bytes, do a move using non-overlapping loads/stores
if it would require no more instructions.

This helps a bit with the case when the move is from a static
constant, because then the code to materialize the value being moved
is smaller.

Change-Id: Ie47a5a7c654afeb4973142b0a9922faea13c9b54
Reviewed-on: https://go-review.googlesource.com/c/146019
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
 2018-10-30 20:27:03 +00:00
Ben Shi
455ef3f6bc test/codegen: improve arithmetic tests 
This CL fixes several typos and adds two more cases
to arithmetic test.

Change-Id: I086560162ea351e2166866e444e2317da36c1729
Reviewed-on: https://go-review.googlesource.com/c/145210
Run-TryBot: Ben Shi <powerman1st@163.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
 2018-10-30 14:39:53 +00:00
Ben Shi
5f5ea3fd4d cmd/compile: optimize amd64's ADDQconstmodify/ADDLconstmodify 
This CL optimize amd64's code:
"ADDQ $-1, MEM_OP" -> "DECQ MEM_OP"
"ADDL $-1, MEM_OP" -> "DECL MEM_OP"

1. The total size of pkg/linux_amd64 (excluding cmd/compile)
decreases about 0.1KB.

2. The go1 benchmark shows little regression, excluding noise.
name                     old time/op    new time/op    delta
BinaryTree17-4              2.60s ± 5%     2.64s ± 3%  +1.53%  (p=0.000 n=38+39)
Fannkuch11-4                2.37s ± 2%     2.38s ± 2%    ~     (p=0.950 n=40+40)
FmtFprintfEmpty-4          40.4ns ± 5%    40.5ns ± 5%    ~     (p=0.711 n=40+40)
FmtFprintfString-4         72.4ns ± 5%    72.3ns ± 3%    ~     (p=0.485 n=40+40)
FmtFprintfInt-4            79.7ns ± 3%    80.1ns ± 3%    ~     (p=0.124 n=40+40)
FmtFprintfIntInt-4          126ns ± 3%     127ns ± 3%  +0.71%  (p=0.027 n=40+40)
FmtFprintfPrefixedInt-4     153ns ± 4%     153ns ± 2%    ~     (p=0.604 n=40+40)
FmtFprintfFloat-4           206ns ± 5%     210ns ± 5%  +1.79%  (p=0.002 n=40+40)
FmtManyArgs-4               498ns ± 3%     496ns ± 3%    ~     (p=0.099 n=40+40)
GobDecode-4                6.48ms ± 6%    6.47ms ± 7%    ~     (p=0.686 n=39+40)
GobEncode-4                5.95ms ± 7%    5.96ms ± 6%    ~     (p=0.670 n=40+34)
Gzip-4                      224ms ± 6%     223ms ± 5%    ~     (p=0.143 n=40+40)
Gunzip-4                   36.5ms ± 4%    36.5ms ± 4%    ~     (p=0.556 n=40+40)
HTTPClientServer-4         60.7µs ± 2%    59.9µs ± 3%  -1.20%  (p=0.000 n=39+39)
JSONEncode-4               9.03ms ± 4%    9.04ms ± 4%    ~     (p=0.589 n=40+40)
JSONDecode-4               49.4ms ± 4%    49.2ms ± 4%    ~     (p=0.276 n=40+40)
Mandelbrot200-4            3.80ms ± 4%    3.79ms ± 4%    ~     (p=0.837 n=40+40)
GoParse-4                  3.15ms ± 5%    3.13ms ± 5%    ~     (p=0.240 n=40+40)
RegexpMatchEasy0_32-4      72.9ns ± 3%    72.0ns ± 8%  -1.25%  (p=0.003 n=40+40)
RegexpMatchEasy0_1K-4       229ns ± 5%     230ns ± 4%    ~     (p=0.318 n=40+40)
RegexpMatchEasy1_32-4      66.9ns ± 3%    67.3ns ± 7%    ~     (p=0.817 n=40+40)
RegexpMatchEasy1_1K-4       371ns ± 5%     370ns ± 4%    ~     (p=0.275 n=40+40)
RegexpMatchMedium_32-4      106ns ± 4%     104ns ± 7%  -2.28%  (p=0.000 n=40+40)
RegexpMatchMedium_1K-4     32.0µs ± 2%    31.4µs ± 3%  -2.08%  (p=0.000 n=40+40)
RegexpMatchHard_32-4       1.54µs ± 7%    1.52µs ± 3%  -1.80%  (p=0.007 n=39+40)
RegexpMatchHard_1K-4       45.8µs ± 4%    45.5µs ± 3%    ~     (p=0.707 n=40+40)
Revcomp-4                   401ms ± 5%     401ms ± 6%    ~     (p=0.935 n=40+40)
Template-4                 62.4ms ± 4%    61.2ms ± 3%  -1.85%  (p=0.000 n=40+40)
TimeParse-4                 315ns ± 2%     318ns ± 3%  +1.10%  (p=0.002 n=40+40)
TimeFormat-4                297ns ± 3%     298ns ± 3%    ~     (p=0.238 n=40+40)
[Geo mean]                 45.8µs         45.7µs       -0.22%

name                     old speed      new speed      delta
GobDecode-4               119MB/s ± 6%   119MB/s ± 7%    ~     (p=0.684 n=39+40)
GobEncode-4               129MB/s ± 7%   128MB/s ± 6%    ~     (p=0.413 n=40+34)
Gzip-4                   86.6MB/s ± 6%  87.0MB/s ± 6%    ~     (p=0.145 n=40+40)
Gunzip-4                  532MB/s ± 4%   532MB/s ± 4%    ~     (p=0.556 n=40+40)
JSONEncode-4              215MB/s ± 4%   215MB/s ± 4%    ~     (p=0.583 n=40+40)
JSONDecode-4             39.3MB/s ± 4%  39.5MB/s ± 4%    ~     (p=0.277 n=40+40)
GoParse-4                18.4MB/s ± 5%  18.5MB/s ± 5%    ~     (p=0.229 n=40+40)
RegexpMatchEasy0_32-4     439MB/s ± 3%   445MB/s ± 8%  +1.28%  (p=0.003 n=40+40)
RegexpMatchEasy0_1K-4    4.46GB/s ± 4%  4.45GB/s ± 4%    ~     (p=0.343 n=40+40)
RegexpMatchEasy1_32-4     479MB/s ± 3%   476MB/s ± 7%    ~     (p=0.855 n=40+40)
RegexpMatchEasy1_1K-4    2.76GB/s ± 5%  2.77GB/s ± 4%    ~     (p=0.250 n=40+40)
RegexpMatchMedium_32-4   9.36MB/s ± 4%  9.58MB/s ± 6%  +2.31%  (p=0.001 n=40+40)
RegexpMatchMedium_1K-4   32.0MB/s ± 2%  32.7MB/s ± 3%  +2.12%  (p=0.000 n=40+40)
RegexpMatchHard_32-4     20.7MB/s ± 7%  21.1MB/s ± 3%  +1.95%  (p=0.005 n=40+40)
RegexpMatchHard_1K-4     22.4MB/s ± 4%  22.5MB/s ± 3%    ~     (p=0.689 n=40+40)
Revcomp-4                 634MB/s ± 5%   634MB/s ± 6%    ~     (p=0.935 n=40+40)
Template-4               31.1MB/s ± 3%  31.7MB/s ± 3%  +1.88%  (p=0.000 n=40+40)
[Geo mean]                129MB/s        130MB/s       +0.62%

Change-Id: I9d61ee810d900920c572cbe89e2f1626bfed12b7
Reviewed-on: https://go-review.googlesource.com/c/145209
Run-TryBot: Ben Shi <powerman1st@163.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
 2018-10-30 00:22:58 +00:00
Keith Randall
9f291d1fc3 cmd/compile: fix rule for combining loads with compares 
Unlike normal load+op opcodes, the load+compare opcode does
not clobber its non-load argument. Allow the load+compare merge
to happen even if the non-load argument is used elsewhere.

Noticed when investigating issue #28417.

Change-Id: Ibc48d1f2e06ae76034c59f453815d263e8ec7288
Reviewed-on: https://go-review.googlesource.com/c/145097
Reviewed-by: Ainar Garipov <gugl.zadolbal@gmail.com>
Reviewed-by: Ben Shi <powerman1st@163.com>
 2018-10-27 00:59:54 +00:00
Keith Randall
dd789550a7 cmd/compile: intrinsify math/bits.Sub on amd64 
name             old time/op  new time/op  delta
Sub-8            1.12ns ± 1%  1.17ns ± 1%   +5.20%          (p=0.008 n=5+5)
Sub32-8          1.11ns ± 0%  1.11ns ± 0%     ~     (all samples are equal)
Sub64-8          1.12ns ± 0%  1.18ns ± 1%   +5.00%          (p=0.016 n=4+5)
Sub64multiple-8  4.10ns ± 1%  0.86ns ± 1%  -78.93%          (p=0.008 n=5+5)

Fixes #28273

Change-Id: Ibcb6f2fd32d987c3bcbae4f4cd9d335a3de98548
Reviewed-on: https://go-review.googlesource.com/c/144258
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
 2018-10-25 19:47:27 +00:00
Keith Randall
899f3a2892 cmd/compile: intrinsify math/bits.Add on amd64 
name             old time/op  new time/op  delta
Add-8            1.11ns ± 0%  1.18ns ± 0%   +6.31%  (p=0.029 n=4+4)
Add32-8          1.02ns ± 0%  1.02ns ± 1%     ~     (p=0.333 n=4+5)
Add64-8          1.11ns ± 1%  1.17ns ± 0%   +5.79%  (p=0.008 n=5+5)
Add64multiple-8  4.35ns ± 1%  0.86ns ± 0%  -80.22%  (p=0.000 n=5+4)

The individual ops are a bit slower (but still very fast).
Using the ops in carry chains is very fast.

Update #28273

Change-Id: Id975f76df2b930abf0e412911d327b6c5b1befe5
Reviewed-on: https://go-review.googlesource.com/c/144257
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
 2018-10-25 19:47:00 +00:00
ChrisALiles
13d5cd7847 cmd/compile: use proved bounds to remove signed division fix-ups 
prove is able to find 94 occurrences in std cmd where a divisor
can't have the value -1. The change removes
the extraneous fix-up code for these cases.

Fixes #25239

Change-Id: Ic184de971f47cc57c702eb72805b8e291c14035d
Reviewed-on: https://go-review.googlesource.com/c/130215
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
 2018-10-23 02:29:44 +00:00
Ben Shi
95dda75bde cmd/compile: optimize store combination on 386/amd64 
This CL add 3 rules to combine byte-store to word-store on386 and
amd64.

Change-Id: Iffd9cda42f1961680c81def4edc773ad58f211b3
Reviewed-on: https://go-review.googlesource.com/c/143057
Run-TryBot: Ben Shi <powerman1st@163.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
 2018-10-19 02:21:04 +00:00
Ben Shi
4158734097 test/codegen: add more combined load/store test cases 
This CL adds more combined load/store test cases for 386/amd64.

Change-Id: I0a483a6ed0212b65c5e84d67ed8c9f50c389ce2d
Reviewed-on: https://go-review.googlesource.com/c/142878
Run-TryBot: Ben Shi <powerman1st@163.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
 2018-10-18 01:57:54 +00:00
Lynn Boger
39fa301bdc test/codegen: enable more tests for ppc64/ppc64le 
Adding cases for ppc64,ppc64le to the codegen tests
where appropriate.

Change-Id: Idf8cbe88a4ab4406a4ef1ea777bd15a58b68f3ed
Reviewed-on: https://go-review.googlesource.com/c/142557
Run-TryBot: Lynn Boger <laboger@linux.vnet.ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
 2018-10-16 19:00:53 +00:00
Ben Shi
4b78fe57a8 cmd/compile: optimize 386's load/store combination 
This CL adds more combinations of two consequtive MOVBload/MOVBstore
to a unique MOVWload/MOVWstore.

1. The size of the go executable decreases about 4KB, and the total
size of pkg/linux_386 (excluding cmd/compile) decreases about 1.5KB.

2. There is no regression in the go1 benchmark result, excluding noise.
name                     old time/op    new time/op    delta
BinaryTree17-4              3.28s ± 2%     3.29s ± 2%    ~     (p=0.151 n=40+40)
Fannkuch11-4                3.52s ± 1%     3.51s ± 1%  -0.28%  (p=0.002 n=40+40)
FmtFprintfEmpty-4          45.4ns ± 4%    45.0ns ± 4%  -0.89%  (p=0.019 n=40+40)
FmtFprintfString-4         81.9ns ± 7%    81.3ns ± 1%    ~     (p=0.660 n=40+25)
FmtFprintfInt-4            91.9ns ± 9%    91.4ns ± 9%    ~     (p=0.249 n=40+40)
FmtFprintfIntInt-4          143ns ± 4%     143ns ± 4%    ~     (p=0.760 n=40+40)
FmtFprintfPrefixedInt-4     184ns ± 3%     183ns ± 4%    ~     (p=0.485 n=40+40)
FmtFprintfFloat-4           408ns ± 3%     409ns ± 3%    ~     (p=0.961 n=40+40)
FmtManyArgs-4               597ns ± 4%     602ns ± 3%    ~     (p=0.413 n=40+40)
GobDecode-4                7.13ms ± 6%    7.14ms ± 6%    ~     (p=0.859 n=40+40)
GobEncode-4                6.86ms ± 9%    6.94ms ± 7%    ~     (p=0.162 n=40+40)
Gzip-4                      395ms ± 4%     396ms ± 3%    ~     (p=0.099 n=40+40)
Gunzip-4                   40.9ms ± 4%    41.1ms ± 3%    ~     (p=0.064 n=40+40)
HTTPClientServer-4         63.6µs ± 2%    63.6µs ± 3%    ~     (p=0.832 n=36+39)
JSONEncode-4               16.1ms ± 3%    15.8ms ± 3%  -1.60%  (p=0.001 n=40+40)
JSONDecode-4               61.0ms ± 3%    61.5ms ± 4%    ~     (p=0.065 n=40+40)
Mandelbrot200-4            5.16ms ± 3%    5.18ms ± 3%    ~     (p=0.056 n=40+40)
GoParse-4                  3.25ms ± 2%    3.23ms ± 3%    ~     (p=0.727 n=40+40)
RegexpMatchEasy0_32-4      90.2ns ± 3%    89.3ns ± 6%  -0.98%  (p=0.002 n=40+40)
RegexpMatchEasy0_1K-4       812ns ± 3%     815ns ± 3%    ~     (p=0.309 n=40+40)
RegexpMatchEasy1_32-4       103ns ± 6%     103ns ± 5%    ~     (p=0.680 n=40+40)
RegexpMatchEasy1_1K-4      1.01µs ± 4%    1.02µs ± 3%    ~     (p=0.326 n=40+33)
RegexpMatchMedium_32-4      120ns ± 4%     120ns ± 5%    ~     (p=0.834 n=40+40)
RegexpMatchMedium_1K-4     40.1µs ± 3%    39.5µs ± 4%  -1.35%  (p=0.000 n=40+40)
RegexpMatchHard_32-4       2.27µs ± 6%    2.23µs ± 4%  -1.67%  (p=0.011 n=40+40)
RegexpMatchHard_1K-4       67.2µs ± 3%    67.2µs ± 3%    ~     (p=0.149 n=40+40)
Revcomp-4                   1.84s ± 2%     1.86s ± 3%  +0.70%  (p=0.020 n=40+40)
Template-4                 69.0ms ± 4%    69.8ms ± 3%  +1.20%  (p=0.003 n=40+40)
TimeParse-4                 438ns ± 3%     439ns ± 4%    ~     (p=0.650 n=40+40)
TimeFormat-4                412ns ± 3%     412ns ± 3%    ~     (p=0.888 n=40+40)
[Geo mean]                 65.2µs         65.2µs       -0.04%

name                     old speed      new speed      delta
GobDecode-4               108MB/s ± 6%   108MB/s ± 6%    ~     (p=0.855 n=40+40)
GobEncode-4               112MB/s ± 9%   111MB/s ± 8%    ~     (p=0.159 n=40+40)
Gzip-4                   49.2MB/s ± 4%  49.1MB/s ± 3%    ~     (p=0.102 n=40+40)
Gunzip-4                  474MB/s ± 3%   472MB/s ± 3%    ~     (p=0.063 n=40+40)
JSONEncode-4              121MB/s ± 3%   123MB/s ± 3%  +1.62%  (p=0.001 n=40+40)
JSONDecode-4             31.9MB/s ± 3%  31.6MB/s ± 4%    ~     (p=0.070 n=40+40)
GoParse-4                17.9MB/s ± 2%  17.9MB/s ± 3%    ~     (p=0.696 n=40+40)
RegexpMatchEasy0_32-4     355MB/s ± 3%   358MB/s ± 5%  +0.99%  (p=0.002 n=40+40)
RegexpMatchEasy0_1K-4    1.26GB/s ± 3%  1.26GB/s ± 3%    ~     (p=0.381 n=40+40)
RegexpMatchEasy1_32-4     310MB/s ± 5%   310MB/s ± 4%    ~     (p=0.655 n=40+40)
RegexpMatchEasy1_1K-4    1.01GB/s ± 4%  1.01GB/s ± 3%    ~     (p=0.351 n=40+33)
RegexpMatchMedium_32-4   8.32MB/s ± 4%  8.34MB/s ± 5%    ~     (p=0.696 n=40+40)
RegexpMatchMedium_1K-4   25.6MB/s ± 3%  25.9MB/s ± 4%  +1.36%  (p=0.000 n=40+40)
RegexpMatchHard_32-4     14.1MB/s ± 6%  14.3MB/s ± 4%  +1.64%  (p=0.011 n=40+40)
RegexpMatchHard_1K-4     15.2MB/s ± 3%  15.2MB/s ± 3%    ~     (p=0.147 n=40+40)
Revcomp-4                 138MB/s ± 2%   137MB/s ± 3%  -0.70%  (p=0.021 n=40+40)
Template-4               28.1MB/s ± 4%  27.8MB/s ± 3%  -1.19%  (p=0.003 n=40+40)
[Geo mean]               83.7MB/s       83.7MB/s       +0.03%

Change-Id: I2a2b3a942b5c45467491515d201179fd192e65c9
Reviewed-on: https://go-review.googlesource.com/c/141650
Run-TryBot: Ben Shi <powerman1st@163.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
 2018-10-16 07:17:11 +00:00
Ben Shi
3785be3093 test/codegen: fix confusing test cases 
ARMv7's MULAF/MULSF/MULAD/MULSD are not fused,
this CL fixes the confusing test cases.

Change-Id: I35022e207e2f0d24a23a7f6f188e41ba8eee9886
Reviewed-on: https://go-review.googlesource.com/c/142439
Run-TryBot: Ben Shi <powerman1st@163.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Akhil Indurti <aindurti@gmail.com>
Reviewed-by: Giovanni Bajo <rasky@develer.com>
 2018-10-16 07:17:02 +00:00
Martin Möhrmann
a0f57c3fd0 cmd/compile: avoid string allocations when map key is struct or array literal 
x = map[string(byteslice)] is already optimized by the compiler to avoid a
string allocation. This CL generalizes this optimization to:

x = map[T1{ ... Tn{..., string(byteslice), ...} ... }]
where T1 to Tn is a nesting of struct and array literals.

Found in a hot code path that used a struct of strings made from []byte
slices to make a map lookup.

There are no uses of the more generalized optimization in the standard library.
Passes toolstash -cmp.

MapStringConversion/32/simple    21.9ns ± 2%    21.9ns ± 3%      ~     (p=0.995 n=17+20)
MapStringConversion/32/struct    28.8ns ± 3%    22.0ns ± 2%   -23.80%  (p=0.000 n=20+20)
MapStringConversion/32/array     28.5ns ± 2%    21.9ns ± 2%   -23.14%  (p=0.000 n=19+16)
MapStringConversion/64/simple    21.0ns ± 2%    21.1ns ± 3%      ~     (p=0.072 n=19+18)
MapStringConversion/64/struct    72.4ns ± 3%    21.3ns ± 2%   -70.53%  (p=0.000 n=20+20)
MapStringConversion/64/array     72.8ns ± 1%    21.0ns ± 2%   -71.13%  (p=0.000 n=17+19)

name                           old allocs/op  new allocs/op  delta
MapStringConversion/32/simple      0.00           0.00           ~     (all equal)
MapStringConversion/32/struct      0.00           0.00           ~     (all equal)
MapStringConversion/32/array       0.00           0.00           ~     (all equal)
MapStringConversion/64/simple      0.00           0.00           ~     (all equal)
MapStringConversion/64/struct      1.00 ± 0%      0.00       -100.00%  (p=0.000 n=20+20)
MapStringConversion/64/array       1.00 ± 0%      0.00       -100.00%  (p=0.000 n=20+20)

Change-Id: I483b4d84d8d74b1025b62c954da9a365e79b7a3a
Reviewed-on: https://go-review.googlesource.com/c/116275
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
 2018-10-15 19:22:07 +00:00
Alberto Donizetti
7c96d87eda test/codegen: test ppc64 TrailingZeros, OnesCount codegen 
This change adds codegen tests for the intrinsification on ppc64 of
the OnesCount{64,32,16,8}, and TrailingZeros{64,32,16,8} math/bits
functions.

Change-Id: Id3364921fbd18316850e15c8c71330c906187fdb
Reviewed-on: https://go-review.googlesource.com/c/141897
Reviewed-by: Lynn Boger <laboger@linux.vnet.ibm.com>
 2018-10-15 16:53:03 +00:00
Ben Shi
93e27e01af test/codegen: add tests of FMA for arm/arm64 
This CL adds tests of fused multiplication-accumulation
on arm/arm64.

Change-Id: Ic85d5277c0d6acb7e1e723653372dfaf96824a39
Reviewed-on: https://go-review.googlesource.com/c/141652
Run-TryBot: Ben Shi <powerman1st@163.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
 2018-10-15 14:51:30 +00:00
Ben Shi
c3208842e1 test/codegen: add tests for multiplication-subtraction 
This CL adds tests for armv7's MULS and arm64's MSUBW.

Change-Id: Id0fd5d26fd477e4ed14389b0d33cad930423eb5b
Reviewed-on: https://go-review.googlesource.com/c/141651
Run-TryBot: Ben Shi <powerman1st@163.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
 2018-10-15 02:41:33 +00:00
Keith Randall
653a4bd8d4 cmd/compile: optimize loads from readonly globals into constants 
Instead of
   MOVB go.string."foo"(SB), AX
do
   MOVB $102, AX

When we know the global we're loading from is readonly, we can
do that read at compile time.

I've made this arch-dependent mostly because the cases where this
happens often are memory->memory moves, and those don't get
decomposed until lowering.

Did amd64/386/arm/arm64. Other architectures could follow.

Update #26498

Change-Id: I41b1dc831b2cd0a52dac9b97f4f4457888a46389
Reviewed-on: https://go-review.googlesource.com/c/141118
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
 2018-10-14 02:54:40 +00:00
Ben Shi
bac6a2925c test/codegen: add more arm64 test cases 
This CL adds 3 combined load test cases for arm64.

Change-Id: I2c67308c40fd8a18f9f2d16c6d12911dcdc583e2
Reviewed-on: https://go-review.googlesource.com/c/140700
Run-TryBot: Ben Shi <powerman1st@163.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
 2018-10-11 15:14:06 +00:00
Ben Shi
27965c1436 cmd/compile: optimize 386's ADDLconstmodifyidx4 
This CL optimize ADDLconstmodifyidx4 to INCL/DECL, when the
constant is +1/-1.

1. The total size of pkg/linux_386/ decreases 28 bytes, excluding
cmd/compile.

2. There is no regression in the go1 benchmark test, excluding noise.
name                     old time/op    new time/op    delta
BinaryTree17-4              3.25s ± 2%     3.23s ± 3%  -0.70%  (p=0.040 n=30+30)
Fannkuch11-4                3.50s ± 1%     3.47s ± 1%  -0.68%  (p=0.000 n=30+30)
FmtFprintfEmpty-4          44.6ns ± 3%    44.8ns ± 3%  +0.46%  (p=0.029 n=30+30)
FmtFprintfString-4         79.0ns ± 3%    78.7ns ± 3%    ~     (p=0.053 n=30+30)
FmtFprintfInt-4            89.2ns ± 2%    89.4ns ± 3%    ~     (p=0.665 n=30+29)
FmtFprintfIntInt-4          142ns ± 3%     142ns ± 3%    ~     (p=0.435 n=30+30)
FmtFprintfPrefixedInt-4     182ns ± 2%     182ns ± 2%    ~     (p=0.964 n=30+30)
FmtFprintfFloat-4           407ns ± 3%     411ns ± 4%    ~     (p=0.080 n=30+30)
FmtManyArgs-4               597ns ± 3%     593ns ± 4%    ~     (p=0.222 n=30+30)
GobDecode-4                7.09ms ± 6%    7.07ms ± 7%    ~     (p=0.633 n=30+30)
GobEncode-4                6.81ms ± 9%    6.81ms ± 8%    ~     (p=0.982 n=30+30)
Gzip-4                      398ms ± 4%     400ms ± 6%    ~     (p=0.177 n=30+30)
Gunzip-4                   41.3ms ± 3%    40.6ms ± 4%  -1.71%  (p=0.005 n=30+30)
HTTPClientServer-4         63.4µs ± 3%    63.4µs ± 4%    ~     (p=0.646 n=30+28)
JSONEncode-4               16.0ms ± 3%    16.1ms ± 3%    ~     (p=0.057 n=30+30)
JSONDecode-4               63.3ms ± 8%    63.1ms ± 7%    ~     (p=0.786 n=30+30)
Mandelbrot200-4            5.17ms ± 3%    5.15ms ± 8%    ~     (p=0.654 n=30+30)
GoParse-4                  3.24ms ± 3%    3.23ms ± 2%    ~     (p=0.091 n=30+30)
RegexpMatchEasy0_32-4       103ns ± 4%     103ns ± 4%    ~     (p=0.575 n=30+30)
RegexpMatchEasy0_1K-4       823ns ± 2%     821ns ± 3%    ~     (p=0.827 n=30+30)
RegexpMatchEasy1_32-4       113ns ± 3%     112ns ± 3%    ~     (p=0.076 n=30+30)
RegexpMatchEasy1_1K-4      1.02µs ± 4%    1.01µs ± 5%    ~     (p=0.087 n=30+30)
RegexpMatchMedium_32-4      129ns ± 3%     127ns ± 4%  -1.55%  (p=0.009 n=30+30)
RegexpMatchMedium_1K-4     39.3µs ± 4%    39.7µs ± 3%    ~     (p=0.054 n=30+30)
RegexpMatchHard_32-4       2.15µs ± 4%    2.15µs ± 4%    ~     (p=0.712 n=30+30)
RegexpMatchHard_1K-4       66.0µs ± 3%    65.1µs ± 3%  -1.32%  (p=0.002 n=30+30)
Revcomp-4                   1.85s ± 2%     1.85s ± 3%    ~     (p=0.168 n=30+30)
Template-4                 69.5ms ± 7%    68.9ms ± 6%    ~     (p=0.250 n=28+28)
TimeParse-4                 434ns ± 3%     432ns ± 4%    ~     (p=0.629 n=30+30)
TimeFormat-4                403ns ± 4%     408ns ± 3%  +1.23%  (p=0.019 n=30+29)
[Geo mean]                 65.5µs         65.3µs       -0.20%

name                     old speed      new speed      delta
GobDecode-4               108MB/s ± 6%   109MB/s ± 6%    ~     (p=0.636 n=30+30)
GobEncode-4               113MB/s ±10%   113MB/s ± 9%    ~     (p=0.982 n=30+30)
Gzip-4                   48.8MB/s ± 4%  48.6MB/s ± 5%    ~     (p=0.178 n=30+30)
Gunzip-4                  470MB/s ± 3%   479MB/s ± 4%  +1.72%  (p=0.006 n=30+30)
JSONEncode-4              121MB/s ± 3%   120MB/s ± 3%    ~     (p=0.057 n=30+30)
JSONDecode-4             30.7MB/s ± 8%  30.8MB/s ± 8%    ~     (p=0.784 n=30+30)
GoParse-4                17.9MB/s ± 3%  17.9MB/s ± 2%    ~     (p=0.090 n=30+30)
RegexpMatchEasy0_32-4     309MB/s ± 4%   309MB/s ± 3%    ~     (p=0.530 n=30+30)
RegexpMatchEasy0_1K-4    1.24GB/s ± 2%  1.25GB/s ± 3%    ~     (p=0.976 n=30+30)
RegexpMatchEasy1_32-4     282MB/s ± 3%   284MB/s ± 3%  +0.81%  (p=0.041 n=30+30)
RegexpMatchEasy1_1K-4    1.00GB/s ± 3%  1.01GB/s ± 4%    ~     (p=0.091 n=30+30)
RegexpMatchMedium_32-4   7.71MB/s ± 3%  7.84MB/s ± 4%  +1.71%  (p=0.000 n=30+30)
RegexpMatchMedium_1K-4   26.1MB/s ± 4%  25.8MB/s ± 3%    ~     (p=0.051 n=30+30)
RegexpMatchHard_32-4     14.9MB/s ± 4%  14.9MB/s ± 4%    ~     (p=0.712 n=30+30)
RegexpMatchHard_1K-4     15.5MB/s ± 3%  15.7MB/s ± 3%  +1.34%  (p=0.003 n=30+30)
Revcomp-4                 138MB/s ± 2%   137MB/s ± 3%    ~     (p=0.174 n=30+30)
Template-4               28.0MB/s ± 6%  28.2MB/s ± 6%    ~     (p=0.251 n=28+28)
[Geo mean]               82.3MB/s       82.6MB/s       +0.36%

Change-Id: I389829699ffe9500a013fcf31be58a97e98043e1
Reviewed-on: https://go-review.googlesource.com/c/140701
Run-TryBot: Ben Shi <powerman1st@163.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
 2018-10-11 01:20:34 +00:00
Keith Randall
ceb0c371d9 cmd/compile: make []byte("...") more efficient 
Do []byte(string) conversions more efficiently when the string
is a constant. Instead of calling stringtobyteslice, allocate
just the space we need and encode the initialization directly.

[]byte("foo") rewrites to the following pseudocode:

var s [3]byte // on heap or stack, depending on whether b escapes
s = *(*[3]byte)(&"foo"[0]) // initialize s from the string
b = s[:]

which generates this assembly:

	0x001d 00029 (tmp1.go:9)	LEAQ	type.[3]uint8(SB), AX
	0x0024 00036 (tmp1.go:9)	MOVQ	AX, (SP)
	0x0028 00040 (tmp1.go:9)	CALL	runtime.newobject(SB)
	0x002d 00045 (tmp1.go:9)	MOVQ	8(SP), AX
	0x0032 00050 (tmp1.go:9)	MOVBLZX	go.string."foo"+2(SB), CX
	0x0039 00057 (tmp1.go:9)	MOVWLZX	go.string."foo"(SB), DX
	0x0040 00064 (tmp1.go:9)	MOVW	DX, (AX)
	0x0043 00067 (tmp1.go:9)	MOVB	CL, 2(AX)
// Then the slice is b = {AX, 3, 3}

The generated code is still not optimal, as it still does load/store
from read-only memory instead of constant stores.  Next CL...

Update #26498
Fixes #10170

Change-Id: I4b990b19f9a308f60c8f4f148934acffefe0a5bd
Reviewed-on: https://go-review.googlesource.com/c/140698
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
 2018-10-10 16:10:40 +00:00
Ben Shi
3933302550 cmd/compile: add indexed form for several 386 instructions 
This CL implements indexed memory operands for the following instructions.
(ADD|SUB|MUL|AND|OR|XOR)Lload -> (ADD|SUB|MUL|AND|OR|XOR)Lloadidx4
(ADD|SUB|AND|OR|XOR)Lmodify -> (ADD|SUB|AND|OR|XOR)Lmodifyidx4
(ADD|AND|OR|XOR)Lconstmodify -> (ADD|AND|OR|XOR)Lconstmodifyidx4

1. The total size of pkg/linux_386/ decreases about 2.5KB, excluding
cmd/compile/ .

2. There is little regression in the go1 benchmark test, excluding noise.
name                     old time/op    new time/op    delta
BinaryTree17-4              3.25s ± 3%     3.25s ± 3%    ~     (p=0.218 n=40+40)
Fannkuch11-4                3.53s ± 1%     3.53s ± 1%    ~     (p=0.303 n=40+40)
FmtFprintfEmpty-4          44.9ns ± 3%    45.6ns ± 3%  +1.48%  (p=0.030 n=40+36)
FmtFprintfString-4         78.7ns ± 5%    80.1ns ± 7%    ~     (p=0.217 n=36+40)
FmtFprintfInt-4            90.2ns ± 6%    89.8ns ± 5%    ~     (p=0.659 n=40+38)
FmtFprintfIntInt-4          140ns ± 5%     141ns ± 5%  +1.00%  (p=0.027 n=40+40)
FmtFprintfPrefixedInt-4     185ns ± 3%     183ns ± 3%    ~     (p=0.104 n=40+40)
FmtFprintfFloat-4           411ns ± 4%     406ns ± 3%  -1.37%  (p=0.005 n=40+40)
FmtManyArgs-4               590ns ± 4%     598ns ± 4%  +1.35%  (p=0.008 n=40+40)
GobDecode-4                7.16ms ± 5%    7.10ms ± 5%    ~     (p=0.335 n=40+40)
GobEncode-4                6.85ms ± 7%    6.74ms ± 9%    ~     (p=0.058 n=38+40)
Gzip-4                      400ms ± 4%     399ms ± 2%  -0.34%  (p=0.003 n=40+33)
Gunzip-4                   41.4ms ± 3%    41.4ms ± 4%  -0.12%  (p=0.020 n=40+40)
HTTPClientServer-4         64.1µs ± 4%    63.5µs ± 2%  -1.07%  (p=0.000 n=39+37)
JSONEncode-4               15.9ms ± 2%    15.9ms ± 3%    ~     (p=0.103 n=40+40)
JSONDecode-4               62.2ms ± 4%    61.6ms ± 3%  -0.98%  (p=0.006 n=39+40)
Mandelbrot200-4            5.18ms ± 3%    5.14ms ± 4%    ~     (p=0.125 n=40+40)
GoParse-4                  3.29ms ± 2%    3.27ms ± 2%  -0.66%  (p=0.006 n=40+40)
RegexpMatchEasy0_32-4       103ns ± 4%     103ns ± 4%    ~     (p=0.632 n=40+40)
RegexpMatchEasy0_1K-4       830ns ± 3%     828ns ± 3%    ~     (p=0.563 n=40+40)
RegexpMatchEasy1_32-4       113ns ± 4%     113ns ± 4%    ~     (p=0.494 n=40+40)
RegexpMatchEasy1_1K-4      1.03µs ± 4%    1.03µs ± 4%    ~     (p=0.665 n=40+40)
RegexpMatchMedium_32-4      130ns ± 4%     129ns ± 3%    ~     (p=0.458 n=40+40)
RegexpMatchMedium_1K-4     39.4µs ± 3%    39.7µs ± 3%    ~     (p=0.825 n=40+40)
RegexpMatchHard_32-4       2.16µs ± 4%    2.15µs ± 4%    ~     (p=0.137 n=40+40)
RegexpMatchHard_1K-4       65.2µs ± 3%    65.4µs ± 4%    ~     (p=0.160 n=40+40)
Revcomp-4                   1.87s ± 2%     1.87s ± 1%  +0.17%  (p=0.019 n=33+33)
Template-4                 69.4ms ± 3%    69.8ms ± 3%  +0.60%  (p=0.009 n=40+40)
TimeParse-4                 437ns ± 4%     438ns ± 4%    ~     (p=0.234 n=40+40)
TimeFormat-4                408ns ± 3%     408ns ± 3%    ~     (p=0.904 n=40+40)
[Geo mean]                 65.7µs         65.6µs       -0.08%

name                     old speed      new speed      delta
GobDecode-4               107MB/s ± 5%   108MB/s ± 5%    ~     (p=0.336 n=40+40)
GobEncode-4               112MB/s ± 6%   114MB/s ± 9%  +1.95%  (p=0.036 n=37+40)
Gzip-4                   48.5MB/s ± 4%  48.6MB/s ± 2%  +0.28%  (p=0.003 n=40+33)
Gunzip-4                  469MB/s ± 4%   469MB/s ± 4%  +0.11%  (p=0.021 n=40+40)
JSONEncode-4              122MB/s ± 2%   122MB/s ± 3%    ~     (p=0.105 n=40+40)
JSONDecode-4             31.2MB/s ± 4%  31.5MB/s ± 4%  +0.99%  (p=0.007 n=39+40)
GoParse-4                17.6MB/s ± 2%  17.7MB/s ± 2%  +0.66%  (p=0.007 n=40+40)
RegexpMatchEasy0_32-4     310MB/s ± 4%   310MB/s ± 4%    ~     (p=0.384 n=40+40)
RegexpMatchEasy0_1K-4    1.23GB/s ± 3%  1.24GB/s ± 3%    ~     (p=0.186 n=40+40)
RegexpMatchEasy1_32-4     283MB/s ± 3%   281MB/s ± 4%    ~     (p=0.855 n=40+40)
RegexpMatchEasy1_1K-4    1.00GB/s ± 4%  1.00GB/s ± 4%    ~     (p=0.665 n=40+40)
RegexpMatchMedium_32-4   7.68MB/s ± 4%  7.73MB/s ± 3%    ~     (p=0.359 n=40+40)
RegexpMatchMedium_1K-4   26.0MB/s ± 3%  25.8MB/s ± 3%    ~     (p=0.825 n=40+40)
RegexpMatchHard_32-4     14.8MB/s ± 3%  14.9MB/s ± 4%    ~     (p=0.136 n=40+40)
RegexpMatchHard_1K-4     15.7MB/s ± 3%  15.7MB/s ± 4%    ~     (p=0.150 n=40+40)
Revcomp-4                 136MB/s ± 1%   136MB/s ± 1%  -0.09%  (p=0.028 n=32+33)
Template-4               28.0MB/s ± 3%  27.8MB/s ± 3%  -0.59%  (p=0.010 n=40+40)
[Geo mean]               82.1MB/s       82.3MB/s       +0.25%

Change-Id: Ifa387a251056678326d3508aa02753b70bf7e5d0
Reviewed-on: https://go-review.googlesource.com/c/140303
Run-TryBot: Ben Shi <powerman1st@163.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
 2018-10-09 03:55:08 +00:00
Carlos Eduardo Seo
9aed4cc395 cmd/compile: instrinsify math/bits.Mul on ppc64x 
Add SSA rules to intrinsify Mul/Mul64 on ppc64x.

benchmark             old ns/op     new ns/op     delta
BenchmarkMul-40       8.80          0.93          -89.43%
BenchmarkMul32-40     1.39          1.39          +0.00%
BenchmarkMul64-40     5.39          0.93          -82.75%

Updates #24813

Change-Id: I6e95bfbe976a2278bd17799df184a7fbc0e57829
Reviewed-on: https://go-review.googlesource.com/138917
Reviewed-by: Lynn Boger <laboger@linux.vnet.ibm.com>
 2018-10-02 18:56:06 +00:00
Ben Shi
5aeecc4530 cmd/compile: optimize arm64's code with more shifted operations 
This CL optimizes arm64's NEG/MVN/TST/CMN with a shifted operand.

1. The total size of pkg/android_arm64 decreases about 0.2KB, excluding
cmd/compile/ .

2. The go1 benchmark shows no regression, excluding noise.
name                     old time/op    new time/op    delta
BinaryTree17-4              16.4s ± 1%     16.4s ± 1%    ~     (p=0.914 n=29+29)
Fannkuch11-4                8.72s ± 0%     8.72s ± 0%    ~     (p=0.274 n=30+29)
FmtFprintfEmpty-4           174ns ± 0%     174ns ± 0%    ~     (all equal)
FmtFprintfString-4          370ns ± 0%     370ns ± 0%    ~     (all equal)
FmtFprintfInt-4             419ns ± 0%     419ns ± 0%    ~     (all equal)
FmtFprintfIntInt-4          672ns ± 1%     675ns ± 2%    ~     (p=0.217 n=28+30)
FmtFprintfPrefixedInt-4     806ns ± 0%     806ns ± 0%    ~     (p=0.402 n=30+28)
FmtFprintfFloat-4          1.09µs ± 0%    1.09µs ± 0%  +0.02%  (p=0.011 n=22+27)
FmtManyArgs-4              2.67µs ± 0%    2.68µs ± 0%    ~     (p=0.279 n=29+30)
GobDecode-4                33.1ms ± 1%    33.1ms ± 0%    ~     (p=0.052 n=28+29)
GobEncode-4                29.6ms ± 0%    29.6ms ± 0%  +0.08%  (p=0.013 n=28+29)
Gzip-4                      1.38s ± 2%     1.39s ± 2%    ~     (p=0.071 n=29+29)
Gunzip-4                    139ms ± 0%     139ms ± 0%    ~     (p=0.265 n=29+29)
HTTPClientServer-4          789µs ± 4%     785µs ± 4%    ~     (p=0.206 n=29+28)
JSONEncode-4               49.7ms ± 0%    49.6ms ± 0%  -0.24%  (p=0.000 n=30+30)
JSONDecode-4                266ms ± 1%     267ms ± 1%  +0.34%  (p=0.000 n=30+30)
Mandelbrot200-4            16.6ms ± 0%    16.6ms ± 0%    ~     (p=0.835 n=28+30)
GoParse-4                  15.9ms ± 0%    15.8ms ± 0%  -0.29%  (p=0.000 n=27+30)
RegexpMatchEasy0_32-4       380ns ± 0%     381ns ± 0%  +0.18%  (p=0.000 n=30+30)
RegexpMatchEasy0_1K-4      1.18µs ± 0%    1.19µs ± 0%  +0.23%  (p=0.000 n=30+30)
RegexpMatchEasy1_32-4       357ns ± 0%     358ns ± 0%  +0.28%  (p=0.000 n=29+29)
RegexpMatchEasy1_1K-4      2.04µs ± 0%    2.04µs ± 0%  +0.06%  (p=0.006 n=30+30)
RegexpMatchMedium_32-4      589ns ± 0%     590ns ± 0%  +0.24%  (p=0.000 n=28+30)
RegexpMatchMedium_1K-4      162µs ± 0%     162µs ± 0%  -0.01%  (p=0.027 n=26+29)
RegexpMatchHard_32-4       9.58µs ± 0%    9.58µs ± 0%    ~     (p=0.935 n=30+30)
RegexpMatchHard_1K-4        287µs ± 0%     287µs ± 0%    ~     (p=0.387 n=29+30)
Revcomp-4                   2.50s ± 0%     2.50s ± 0%  -0.10%  (p=0.020 n=28+28)
Template-4                  310ms ± 0%     310ms ± 1%    ~     (p=0.406 n=30+30)
TimeParse-4                1.68µs ± 0%    1.68µs ± 0%  +0.03%  (p=0.014 n=30+17)
TimeFormat-4               1.65µs ± 0%    1.66µs ± 0%  +0.32%  (p=0.000 n=27+29)
[Geo mean]                  247µs          247µs       +0.05%

name                     old speed      new speed      delta
GobDecode-4              23.2MB/s ± 0%  23.2MB/s ± 0%  -0.08%  (p=0.032 n=27+29)
GobEncode-4              26.0MB/s ± 0%  25.9MB/s ± 0%  -0.10%  (p=0.011 n=29+29)
Gzip-4                   14.1MB/s ± 2%  14.0MB/s ± 2%    ~     (p=0.081 n=29+29)
Gunzip-4                  139MB/s ± 0%   139MB/s ± 0%    ~     (p=0.290 n=29+29)
JSONEncode-4             39.0MB/s ± 0%  39.1MB/s ± 0%  +0.25%  (p=0.000 n=29+30)
JSONDecode-4             7.30MB/s ± 1%  7.28MB/s ± 1%  -0.33%  (p=0.000 n=30+30)
GoParse-4                3.65MB/s ± 0%  3.66MB/s ± 0%  +0.29%  (p=0.000 n=27+30)
RegexpMatchEasy0_32-4    84.1MB/s ± 0%  84.0MB/s ± 0%  -0.17%  (p=0.000 n=30+28)
RegexpMatchEasy0_1K-4     864MB/s ± 0%   862MB/s ± 0%  -0.24%  (p=0.000 n=30+30)
RegexpMatchEasy1_32-4    89.5MB/s ± 0%  89.3MB/s ± 0%  -0.18%  (p=0.000 n=28+24)
RegexpMatchEasy1_1K-4     502MB/s ± 0%   502MB/s ± 0%  -0.05%  (p=0.008 n=30+29)
RegexpMatchMedium_32-4   1.70MB/s ± 0%  1.69MB/s ± 0%  -0.59%  (p=0.000 n=29+30)
RegexpMatchMedium_1K-4   6.31MB/s ± 0%  6.31MB/s ± 0%  +0.05%  (p=0.005 n=30+26)
RegexpMatchHard_32-4     3.34MB/s ± 0%  3.34MB/s ± 0%    ~     (all equal)
RegexpMatchHard_1K-4     3.57MB/s ± 0%  3.57MB/s ± 0%    ~     (all equal)
Revcomp-4                 102MB/s ± 0%   102MB/s ± 0%  +0.10%  (p=0.022 n=28+28)
Template-4               6.26MB/s ± 0%  6.26MB/s ± 1%    ~     (p=0.768 n=30+30)
[Geo mean]               24.2MB/s       24.1MB/s       -0.08%

Change-Id: I494f9db7f8a568a00e9c74ae25086a58b2221683
Reviewed-on: https://go-review.googlesource.com/137976
Run-TryBot: Ben Shi <powerman1st@163.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
 2018-09-28 15:05:17 +00:00
Ben Shi
d60cf39f8e cmd/compile: optimize arm64's MADD and MSUB 
This CL implements constant folding for MADD/MSUB on arm64.

1. The total size of pkg/android_arm64/ decreases about 4KB,
   excluding cmd/compile/ .

2. There is no regression in the go1 benchmark, excluding noise.
name                     old time/op    new time/op    delta
BinaryTree17-4              16.4s ± 1%     16.5s ± 1%  +0.24%  (p=0.008 n=29+29)
Fannkuch11-4                8.73s ± 0%     8.71s ± 0%  -0.15%  (p=0.000 n=29+29)
FmtFprintfEmpty-4           174ns ± 0%     174ns ± 0%    ~     (all equal)
FmtFprintfString-4          370ns ± 0%     372ns ± 2%  +0.53%  (p=0.007 n=24+30)
FmtFprintfInt-4             419ns ± 0%     419ns ± 0%    ~     (all equal)
FmtFprintfIntInt-4          673ns ± 1%     661ns ± 1%  -1.81%  (p=0.000 n=30+27)
FmtFprintfPrefixedInt-4     806ns ± 0%     805ns ± 0%    ~     (p=0.957 n=28+27)
FmtFprintfFloat-4          1.09µs ± 0%    1.09µs ± 0%  -0.04%  (p=0.001 n=22+30)
FmtManyArgs-4              2.67µs ± 0%    2.68µs ± 0%  +0.03%  (p=0.045 n=29+28)
GobDecode-4                33.2ms ± 1%    32.5ms ± 1%  -2.11%  (p=0.000 n=29+29)
GobEncode-4                29.5ms ± 0%    29.2ms ± 0%  -1.04%  (p=0.000 n=28+28)
Gzip-4                      1.39s ± 2%     1.38s ± 1%  -0.48%  (p=0.023 n=30+30)
Gunzip-4                    139ms ± 0%     139ms ± 0%    ~     (p=0.616 n=30+28)
HTTPClientServer-4          766µs ± 4%     758µs ± 3%  -1.03%  (p=0.013 n=28+29)
JSONEncode-4               49.7ms ± 0%    49.6ms ± 0%  -0.24%  (p=0.000 n=30+30)
JSONDecode-4                266ms ± 0%     268ms ± 1%  +1.07%  (p=0.000 n=29+30)
Mandelbrot200-4            16.6ms ± 0%    16.6ms ± 0%    ~     (p=0.248 n=30+29)
GoParse-4                  15.9ms ± 0%    16.0ms ± 0%  +0.76%  (p=0.000 n=29+29)
RegexpMatchEasy0_32-4       381ns ± 0%     380ns ± 0%  -0.14%  (p=0.000 n=30+30)
RegexpMatchEasy0_1K-4      1.18µs ± 0%    1.19µs ± 1%  +0.30%  (p=0.000 n=29+30)
RegexpMatchEasy1_32-4       357ns ± 0%     357ns ± 0%    ~     (all equal)
RegexpMatchEasy1_1K-4      2.04µs ± 0%    2.05µs ± 0%  +0.50%  (p=0.000 n=26+28)
RegexpMatchMedium_32-4      590ns ± 0%     589ns ± 0%  -0.12%  (p=0.000 n=30+23)
RegexpMatchMedium_1K-4      162µs ± 0%     162µs ± 0%    ~     (p=0.318 n=28+25)
RegexpMatchHard_32-4       9.56µs ± 0%    9.56µs ± 0%    ~     (p=0.072 n=30+29)
RegexpMatchHard_1K-4        287µs ± 0%     287µs ± 0%  -0.02%  (p=0.005 n=28+28)
Revcomp-4                   2.50s ± 0%     2.51s ± 0%    ~     (p=0.246 n=29+29)
Template-4                  312ms ± 1%     313ms ± 1%  +0.46%  (p=0.002 n=30+30)
TimeParse-4                1.68µs ± 0%    1.67µs ± 0%  -0.31%  (p=0.000 n=27+29)
TimeFormat-4               1.66µs ± 0%    1.64µs ± 0%  -0.92%  (p=0.000 n=29+26)
[Geo mean]                  247µs          246µs       -0.15%

name                     old speed      new speed      delta
GobDecode-4              23.1MB/s ± 1%  23.6MB/s ± 0%  +2.17%  (p=0.000 n=29+28)
GobEncode-4              26.0MB/s ± 0%  26.3MB/s ± 0%  +1.05%  (p=0.000 n=28+28)
Gzip-4                   14.0MB/s ± 2%  14.1MB/s ± 1%  +0.47%  (p=0.026 n=30+30)
Gunzip-4                  139MB/s ± 0%   139MB/s ± 0%    ~     (p=0.624 n=30+28)
JSONEncode-4             39.1MB/s ± 0%  39.2MB/s ± 0%  +0.24%  (p=0.000 n=30+30)
JSONDecode-4             7.31MB/s ± 0%  7.23MB/s ± 1%  -1.07%  (p=0.000 n=28+30)
GoParse-4                3.65MB/s ± 0%  3.62MB/s ± 0%  -0.77%  (p=0.000 n=29+29)
RegexpMatchEasy0_32-4    84.0MB/s ± 0%  84.1MB/s ± 0%  +0.18%  (p=0.000 n=28+30)
RegexpMatchEasy0_1K-4     864MB/s ± 0%   861MB/s ± 1%  -0.29%  (p=0.000 n=29+30)
RegexpMatchEasy1_32-4    89.5MB/s ± 0%  89.5MB/s ± 0%    ~     (p=0.841 n=28+28)
RegexpMatchEasy1_1K-4     502MB/s ± 0%   500MB/s ± 0%  -0.51%  (p=0.000 n=29+29)
RegexpMatchMedium_32-4   1.69MB/s ± 0%  1.70MB/s ± 0%  +0.41%  (p=0.000 n=26+30)
RegexpMatchMedium_1K-4   6.31MB/s ± 0%  6.30MB/s ± 0%    ~     (p=0.129 n=30+25)
RegexpMatchHard_32-4     3.35MB/s ± 0%  3.35MB/s ± 0%    ~     (p=0.657 n=30+29)
RegexpMatchHard_1K-4     3.57MB/s ± 0%  3.57MB/s ± 0%    ~     (all equal)
Revcomp-4                 102MB/s ± 0%   101MB/s ± 0%    ~     (p=0.213 n=29+29)
Template-4               6.22MB/s ± 1%  6.19MB/s ± 1%  -0.42%  (p=0.005 n=30+29)
[Geo mean]               24.1MB/s       24.2MB/s       +0.08%

Change-Id: I6c02d3c9975f6bd8bc215cb1fc14d29602b45649
Reviewed-on: https://go-review.googlesource.com/138095
Run-TryBot: Ben Shi <powerman1st@163.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
 2018-09-28 15:03:17 +00:00
Brian Kessler
9eb53ab9bc cmd/compile: intrinsify math/bits.Mul 
Add SSA rules to intrinsify Mul/Mul64 (AMD64 and ARM64).
SSA rules for other functions and architectures are left as a future
optimization.  Benchmark results on AMD64/ARM64 before and after SSA
implementation are below.

amd64
name     old time/op  new time/op  delta
Add-4    1.78ns ± 0%  1.85ns ±12%     ~     (p=0.397 n=4+5)
Add32-4  1.71ns ± 1%  1.70ns ± 0%     ~     (p=0.683 n=5+5)
Add64-4  1.80ns ± 2%  1.77ns ± 0%   -1.22%  (p=0.048 n=5+5)
Sub-4    1.78ns ± 0%  1.78ns ± 0%     ~     (all equal)
Sub32-4  1.78ns ± 1%  1.78ns ± 0%     ~     (p=1.000 n=5+5)
Sub64-4  1.78ns ± 1%  1.78ns ± 0%     ~     (p=0.968 n=5+4)
Mul-4    11.5ns ± 1%   1.8ns ± 2%  -84.39%  (p=0.008 n=5+5)
Mul32-4  1.39ns ± 0%  1.38ns ± 3%     ~     (p=0.175 n=5+5)
Mul64-4  6.85ns ± 1%  1.78ns ± 1%  -73.97%  (p=0.008 n=5+5)
Div-4    57.1ns ± 1%  56.7ns ± 0%     ~     (p=0.087 n=5+5)
Div32-4  18.0ns ± 0%  18.0ns ± 0%     ~     (all equal)
Div64-4  56.4ns ±10%  53.6ns ± 1%     ~     (p=0.071 n=5+5)

arm64
name      old time/op  new time/op  delta
Add-96    5.51ns ± 0%  5.51ns ± 0%     ~     (all equal)
Add32-96  5.51ns ± 0%  5.51ns ± 0%     ~     (all equal)
Add64-96  5.52ns ± 0%  5.51ns ± 0%     ~     (p=0.444 n=5+5)
Sub-96    5.51ns ± 0%  5.51ns ± 0%     ~     (all equal)
Sub32-96  5.51ns ± 0%  5.51ns ± 0%     ~     (all equal)
Sub64-96  5.51ns ± 0%  5.51ns ± 0%     ~     (all equal)
Mul-96    34.6ns ± 0%   5.0ns ± 0%  -85.52%  (p=0.008 n=5+5)
Mul32-96  4.51ns ± 0%  4.51ns ± 0%     ~     (all equal)
Mul64-96  21.1ns ± 0%   5.0ns ± 0%  -76.26%  (p=0.008 n=5+5)
Div-96    64.7ns ± 0%  64.7ns ± 0%     ~     (all equal)
Div32-96  17.0ns ± 0%  17.0ns ± 0%     ~     (all equal)
Div64-96  53.1ns ± 0%  53.1ns ± 0%     ~     (all equal)

Updates #24813

Change-Id: I9bda6d2102f65cae3d436a2087b47ed8bafeb068
Reviewed-on: https://go-review.googlesource.com/129415
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
 2018-09-26 20:35:57 +00:00
Iskander Sharipov
c03d0e4fec cmd/compile/internal/gc: handle arith ops in samesafeexpr 
Teach samesafeexpr to handle arithmetic unary and binary ops.

It makes map lookup optimization possible in

	m[k+1] = append(m[k+1], ...)
	m[-k] = append(m[-k], ...)
	... etc

Does not cover "+" for strings (concatenation).

Change-Id: Ibbb16ac3faf176958da344be1471b06d7cf33a6c
Reviewed-on: https://go-review.googlesource.com/135795
Run-TryBot: Iskander Sharipov <iskander.sharipov@intel.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
 2018-09-19 12:03:58 +00:00
Ben Shi
c6bf9a8109 cmd/compile: optimize AMD64's bit wise operation 
Currently "arr[idx] |= 0x80" is compiled to MOVLload->BTSL->MOVLstore.
And this CL optimizes it to a single BTSLconstmodify. Other bit wise
operations with a direct memory operand are also implemented.

1. The size of the executable bin/go decreases about 4KB, and the total size
of pkg/linux_amd64 (excluding cmd/compile) decreases about 0.6KB.

2. There a little improvement in the go1 benchmark test (excluding noise).
name                     old time/op    new time/op    delta
BinaryTree17-4              2.66s ± 4%     2.66s ± 3%    ~     (p=0.596 n=49+49)
Fannkuch11-4                2.38s ± 2%     2.32s ± 2%  -2.69%  (p=0.000 n=50+50)
FmtFprintfEmpty-4          42.7ns ± 4%    43.2ns ± 7%  +1.31%  (p=0.009 n=50+50)
FmtFprintfString-4         71.0ns ± 5%    72.0ns ± 3%  +1.33%  (p=0.000 n=50+50)
FmtFprintfInt-4            80.7ns ± 4%    80.6ns ± 3%    ~     (p=0.931 n=50+50)
FmtFprintfIntInt-4          125ns ± 3%     126ns ± 4%    ~     (p=0.051 n=50+50)
FmtFprintfPrefixedInt-4     158ns ± 1%     142ns ± 3%  -9.84%  (p=0.000 n=36+50)
FmtFprintfFloat-4           215ns ± 4%     212ns ± 4%  -1.23%  (p=0.002 n=50+50)
FmtManyArgs-4               519ns ± 3%     510ns ± 3%  -1.77%  (p=0.000 n=50+50)
GobDecode-4                6.49ms ± 6%    6.52ms ± 5%    ~     (p=0.866 n=50+50)
GobEncode-4                5.93ms ± 8%    6.01ms ± 7%    ~     (p=0.076 n=50+50)
Gzip-4                      222ms ± 4%     224ms ± 8%  +0.80%  (p=0.001 n=50+50)
Gunzip-4                   36.6ms ± 5%    36.4ms ± 4%    ~     (p=0.093 n=50+50)
HTTPClientServer-4         59.1µs ± 1%    58.9µs ± 2%  -0.24%  (p=0.039 n=49+48)
JSONEncode-4               9.23ms ± 4%    9.21ms ± 5%    ~     (p=0.244 n=50+50)
JSONDecode-4               48.8ms ± 4%    48.7ms ± 4%    ~     (p=0.653 n=50+50)
Mandelbrot200-4            3.81ms ± 4%    3.80ms ± 3%    ~     (p=0.834 n=50+50)
GoParse-4                  3.20ms ± 5%    3.19ms ± 5%    ~     (p=0.494 n=50+50)
RegexpMatchEasy0_32-4      78.1ns ± 2%    77.4ns ± 3%  -0.86%  (p=0.005 n=50+50)
RegexpMatchEasy0_1K-4       233ns ± 3%     233ns ± 3%    ~     (p=0.074 n=50+50)
RegexpMatchEasy1_32-4      74.2ns ± 3%    73.4ns ± 3%  -1.06%  (p=0.000 n=50+50)
RegexpMatchEasy1_1K-4       369ns ± 2%     364ns ± 4%  -1.41%  (p=0.000 n=36+50)
RegexpMatchMedium_32-4      109ns ± 4%     107ns ± 3%  -2.06%  (p=0.001 n=50+50)
RegexpMatchMedium_1K-4     31.5µs ± 3%    30.8µs ± 3%  -2.20%  (p=0.000 n=50+50)
RegexpMatchHard_32-4       1.57µs ± 3%    1.56µs ± 2%  -0.57%  (p=0.016 n=50+50)
RegexpMatchHard_1K-4       47.4µs ± 4%    47.0µs ± 3%  -0.82%  (p=0.008 n=50+50)
Revcomp-4                   414ms ± 7%     412ms ± 7%    ~     (p=0.285 n=50+50)
Template-4                 64.3ms ± 4%    62.7ms ± 3%  -2.44%  (p=0.000 n=50+50)
TimeParse-4                 316ns ± 3%     313ns ± 3%    ~     (p=0.122 n=50+50)
TimeFormat-4                291ns ± 3%     293ns ± 3%  +0.80%  (p=0.001 n=50+50)
[Geo mean]                 46.5µs         46.2µs       -0.81%

name                     old speed      new speed      delta
GobDecode-4               118MB/s ± 6%   118MB/s ± 5%    ~     (p=0.863 n=50+50)
GobEncode-4               130MB/s ± 9%   128MB/s ± 8%    ~     (p=0.076 n=50+50)
Gzip-4                   87.4MB/s ± 4%  86.8MB/s ± 7%  -0.78%  (p=0.002 n=50+50)
Gunzip-4                  531MB/s ± 5%   533MB/s ± 4%    ~     (p=0.093 n=50+50)
JSONEncode-4              210MB/s ± 4%   211MB/s ± 5%    ~     (p=0.247 n=50+50)
JSONDecode-4             39.8MB/s ± 4%  39.9MB/s ± 4%    ~     (p=0.654 n=50+50)
GoParse-4                18.1MB/s ± 5%  18.2MB/s ± 5%    ~     (p=0.493 n=50+50)
RegexpMatchEasy0_32-4     410MB/s ± 2%   413MB/s ± 3%  +0.86%  (p=0.004 n=50+50)
RegexpMatchEasy0_1K-4    4.39GB/s ± 3%  4.38GB/s ± 3%    ~     (p=0.063 n=50+50)
RegexpMatchEasy1_32-4     432MB/s ± 3%   436MB/s ± 3%  +1.07%  (p=0.000 n=50+50)
RegexpMatchEasy1_1K-4    2.77GB/s ± 2%  2.81GB/s ± 4%  +1.46%  (p=0.000 n=36+50)
RegexpMatchMedium_32-4   9.16MB/s ± 3%  9.35MB/s ± 4%  +2.09%  (p=0.001 n=50+50)
RegexpMatchMedium_1K-4   32.5MB/s ± 3%  33.2MB/s ± 3%  +2.25%  (p=0.000 n=50+50)
RegexpMatchHard_32-4     20.4MB/s ± 3%  20.5MB/s ± 2%  +0.56%  (p=0.017 n=50+50)
RegexpMatchHard_1K-4     21.6MB/s ± 4%  21.8MB/s ± 3%  +0.83%  (p=0.008 n=50+50)
Revcomp-4                 613MB/s ± 4%   618MB/s ± 7%    ~     (p=0.152 n=48+50)
Template-4               30.2MB/s ± 4%  30.9MB/s ± 3%  +2.49%  (p=0.000 n=50+50)
[Geo mean]                127MB/s        128MB/s       +0.64%

Change-Id: If405198283855d75697f66cf894b2bef458f620e
Reviewed-on: https://go-review.googlesource.com/135422
Reviewed-by: Keith Randall <khr@golang.org>
 2018-09-19 03:00:58 +00:00
fanzha02
a19a83c8ef cmd/compile: optimize math.Float64(32)bits and math.Float64(32)frombits on arm64 
Use float <-> int register moves without conversion instead of stores
and loads to move float <-> int values.

Math package benchmark results.
name                 old time/op  new time/op  delta
Acosh                 153ns ± 0%   147ns ± 0%   -3.92%  (p=0.000 n=10+10)
Asinh                 183ns ± 0%   177ns ± 0%   -3.28%  (p=0.000 n=10+10)
Atanh                 157ns ± 0%   155ns ± 0%   -1.27%  (p=0.000 n=10+10)
Atan2                 118ns ± 0%   117ns ± 1%   -0.59%  (p=0.003 n=10+10)
Cbrt                  119ns ± 0%   114ns ± 0%   -4.20%  (p=0.000 n=10+10)
Copysign             7.51ns ± 0%  6.51ns ± 0%  -13.32%  (p=0.000 n=9+10)
Cos                  73.1ns ± 0%  70.6ns ± 0%   -3.42%  (p=0.000 n=10+10)
Cosh                  119ns ± 0%   121ns ± 0%   +1.68%  (p=0.000 n=10+9)
ExpGo                 154ns ± 0%   149ns ± 0%   -3.05%  (p=0.000 n=9+10)
Expm1                 101ns ± 0%    99ns ± 0%   -1.88%  (p=0.000 n=10+10)
Exp2Go                150ns ± 0%   146ns ± 0%   -2.67%  (p=0.000 n=10+10)
Abs                  7.01ns ± 0%  6.01ns ± 0%  -14.27%  (p=0.000 n=10+9)
Mod                   234ns ± 0%   212ns ± 0%   -9.40%  (p=0.000 n=9+10)
Frexp                34.5ns ± 0%  30.0ns ± 0%  -13.04%  (p=0.000 n=10+10)
Gamma                 112ns ± 0%   111ns ± 0%   -0.89%  (p=0.000 n=10+10)
Hypot                73.6ns ± 0%  68.6ns ± 0%   -6.79%  (p=0.000 n=10+10)
HypotGo              77.1ns ± 0%  72.1ns ± 0%   -6.49%  (p=0.000 n=10+10)
Ilogb                31.0ns ± 0%  28.0ns ± 0%   -9.68%  (p=0.000 n=10+10)
J0                    437ns ± 0%   434ns ± 0%   -0.62%  (p=0.000 n=10+10)
J1                    433ns ± 0%   431ns ± 0%   -0.46%  (p=0.000 n=10+10)
Jn                    927ns ± 0%   922ns ± 0%   -0.54%  (p=0.000 n=10+10)
Ldexp                41.5ns ± 0%  37.0ns ± 0%  -10.84%  (p=0.000 n=9+10)
Log                   124ns ± 0%   118ns ± 0%   -4.84%  (p=0.000 n=10+9)
Logb                 34.0ns ± 0%  32.0ns ± 0%   -5.88%  (p=0.000 n=10+10)
Log1p                 110ns ± 0%   108ns ± 0%   -1.82%  (p=0.000 n=10+10)
Log10                 136ns ± 0%   132ns ± 0%   -2.94%  (p=0.000 n=10+10)
Log2                 51.6ns ± 0%  47.1ns ± 0%   -8.72%  (p=0.000 n=10+10)
Nextafter32          33.0ns ± 0%  30.5ns ± 0%   -7.58%  (p=0.000 n=10+10)
Nextafter64          29.0ns ± 0%  26.5ns ± 0%   -8.62%  (p=0.000 n=10+10)
PowInt                169ns ± 0%   160ns ± 0%   -5.33%  (p=0.000 n=10+10)
PowFrac               375ns ± 0%   361ns ± 0%   -3.73%  (p=0.000 n=10+10)
RoundToEven          14.0ns ± 0%  12.5ns ± 0%  -10.71%  (p=0.000 n=10+10)
Remainder             206ns ± 0%   192ns ± 0%   -6.80%  (p=0.000 n=10+9)
Signbit              6.01ns ± 0%  5.51ns ± 0%   -8.32%  (p=0.000 n=10+9)
Sin                  70.1ns ± 0%  69.6ns ± 0%   -0.71%  (p=0.000 n=10+10)
Sincos               99.1ns ± 0%  99.6ns ± 0%   +0.50%  (p=0.000 n=9+10)
SqrtGoLatency         178ns ± 0%   146ns ± 0%  -17.70%  (p=0.000 n=8+10)
SqrtPrime            9.19µs ± 0%  9.20µs ± 0%   +0.01%  (p=0.000 n=9+9)
Tanh                  125ns ± 1%   127ns ± 0%   +1.36%  (p=0.000 n=10+10)
Y0                    428ns ± 0%   426ns ± 0%   -0.47%  (p=0.000 n=10+10)
Y1                    431ns ± 0%   429ns ± 0%   -0.46%  (p=0.000 n=10+9)
Yn                    906ns ± 0%   901ns ± 0%   -0.55%  (p=0.000 n=10+10)
Float64bits          4.50ns ± 0%  3.50ns ± 0%  -22.22%  (p=0.000 n=10+10)
Float64frombits      4.00ns ± 0%  3.50ns ± 0%  -12.50%  (p=0.000 n=10+9)
Float32bits          4.50ns ± 0%  3.50ns ± 0%  -22.22%  (p=0.002 n=8+10)
Float32frombits      4.00ns ± 0%  3.50ns ± 0%  -12.50%  (p=0.000 n=10+10)

Change-Id: Iba829e15d5624962fe0c699139ea783efeefabc2
Reviewed-on: https://go-review.googlesource.com/129715
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
 2018-09-17 20:49:04 +00:00
Keith Randall
b1f656b1ce cmd/compile: fold address calculations into CMPload[const] ops 
Makes go binary smaller by 0.2%.

I noticed this in autogenerated equal methods, and there are
probably a lot of those.

Change-Id: I4e04eb3653fbceb9dd6a4eee97ceab1fa4d10b72
Reviewed-on: https://go-review.googlesource.com/135379
Reviewed-by: Ilya Tocar <ilya.tocar@intel.com>
 2018-09-14 19:42:09 +00:00
Lynn Boger
8dbd9afbb0 cmd/compile: improve rules for PPC64.rules 
This adds some improvements to the rules for PPC64 to eliminate
unnecessary zero or sign extends, and fix some rule for truncates
which were not always using the correct sign instruction.

This reduces of size of many functions by 1 or 2 instructions and
can improve performance in cases where the execution time depends
on small loops where at least 1 instruction was removed and where that
loop contributes a significant amount of the total execution time.

Included is a testcase for codegen to verify the sign/zero extend
instructions are omitted.

An example of the improvement (strings):
IndexAnyASCII/256:1-16     392ns ± 0%   369ns ± 0%  -5.79%  (p=0.000 n=1+10)
IndexAnyASCII/256:2-16     397ns ± 0%   376ns ± 0%  -5.23%  (p=0.000 n=1+9)
IndexAnyASCII/256:4-16     405ns ± 0%   384ns ± 0%  -5.19%  (p=1.714 n=1+6)
IndexAnyASCII/256:8-16     427ns ± 0%   403ns ± 0%  -5.57%  (p=0.000 n=1+10)
IndexAnyASCII/256:16-16    441ns ± 0%   418ns ± 1%  -5.33%  (p=0.000 n=1+10)
IndexAnyASCII/4096:1-16   5.62µs ± 0%  5.27µs ± 1%  -6.31%  (p=0.000 n=1+10)
IndexAnyASCII/4096:2-16   5.67µs ± 0%  5.29µs ± 0%  -6.67%  (p=0.222 n=1+8)
IndexAnyASCII/4096:4-16   5.66µs ± 0%  5.28µs ± 1%  -6.66%  (p=0.000 n=1+10)
IndexAnyASCII/4096:8-16   5.66µs ± 0%  5.31µs ± 1%  -6.10%  (p=0.000 n=1+10)
IndexAnyASCII/4096:16-16  5.70µs ± 0%  5.33µs ± 1%  -6.43%  (p=0.182 n=1+10)

Change-Id: I739a6132b505936d39001aada5a978ff2a5f0500
Reviewed-on: https://go-review.googlesource.com/129875
Reviewed-by: David Chase <drchase@google.com>
 2018-09-13 18:24:53 +00:00
erifan01
8149db4f64 cmd/compile: intrinsify math.RoundToEven and math.Abs on arm64 
math.RoundToEven can be done by one arm64 instruction FRINTND, intrinsify it to improve performance.
The current pure Go implementation of the function Abs is translated into five instructions on arm64:
str, ldr, and, str, ldr. The intrinsic implementation requires only one instruction, so in terms of
performance, intrinsify it is worthwhile.

Benchmarks:
name           old time/op  new time/op  delta
Abs-8          3.50ns ± 0%  1.50ns ± 0%  -57.14%  (p=0.000 n=10+10)
RoundToEven-8  9.26ns ± 0%  1.50ns ± 0%  -83.80%  (p=0.000 n=10+10)

Change-Id: I9456b26ab282b544dfac0154fc86f17aed96ac3d
Reviewed-on: https://go-review.googlesource.com/116535
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
 2018-09-13 14:52:51 +00:00
fanzha02
d5377c2026 test: fix the wrong test of math.Copysign(c, -1) for arm64 
The CL 132915 added the wrong codegen test for math.Copysign(c, -1),
it should test that AND is not emitted. This CL fixes this error.

Change-Id: Ida1d3d54ebfc7f238abccbc1f70f914e1b5bfd91
Reviewed-on: https://go-review.googlesource.com/134815
Reviewed-by: Giovanni Bajo <rasky@develer.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Giovanni Bajo <rasky@develer.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
 2018-09-12 15:34:20 +00:00
Ben Shi
9f2411894b cmd/compile: optimize arm's bit operation 
BFC (Bit Field Clear) was introduced in ARMv7, which can simplify
ANDconst and BICconst. And this CL implements that optimization.

1. The total size of pkg/android_arm decreases about 3KB, excluding
cmd/compile/.

2. There is no regression in the go1 benchmark result, and some
cases (FmtFprintfEmpty-4 and RegexpMatchMedium_32-4) even get
slight improvement.

name                     old time/op    new time/op    delta
BinaryTree17-4              25.3s ± 1%     25.2s ± 1%    ~     (p=0.072 n=30+29)
Fannkuch11-4                13.3s ± 0%     13.3s ± 0%  +0.13%  (p=0.000 n=30+26)
FmtFprintfEmpty-4           407ns ± 0%     394ns ± 0%  -3.19%  (p=0.000 n=26+28)
FmtFprintfString-4          664ns ± 0%     662ns ± 0%  -0.22%  (p=0.000 n=30+30)
FmtFprintfInt-4             712ns ± 0%     706ns ± 0%  -0.79%  (p=0.000 n=30+30)
FmtFprintfIntInt-4         1.06µs ± 0%    1.05µs ± 0%  -0.38%  (p=0.000 n=30+30)
FmtFprintfPrefixedInt-4    1.16µs ± 0%    1.16µs ± 0%  -0.13%  (p=0.000 n=30+29)
FmtFprintfFloat-4          2.24µs ± 0%    2.23µs ± 0%  -0.51%  (p=0.000 n=29+21)
FmtManyArgs-4              4.09µs ± 0%    4.06µs ± 0%  -0.83%  (p=0.000 n=28+30)
GobDecode-4                55.0ms ± 5%    55.4ms ± 5%    ~     (p=0.307 n=30+30)
GobEncode-4                51.2ms ± 1%    51.9ms ± 1%  +1.23%  (p=0.000 n=29+30)
Gzip-4                      2.64s ± 0%     2.60s ± 0%  -1.35%  (p=0.000 n=30+29)
Gunzip-4                    309ms ± 0%     308ms ± 0%  -0.27%  (p=0.000 n=30+30)
HTTPClientServer-4         1.03ms ± 5%    1.02ms ± 4%    ~     (p=0.117 n=30+29)
JSONEncode-4                101ms ± 2%     101ms ± 2%    ~     (p=0.338 n=29+29)
JSONDecode-4                383ms ± 2%     382ms ± 2%    ~     (p=0.751 n=26+30)
Mandelbrot200-4            18.4ms ± 0%    18.4ms ± 0%  -0.10%  (p=0.000 n=29+29)
GoParse-4                  22.6ms ± 0%    22.5ms ± 0%  -0.39%  (p=0.000 n=30+30)
RegexpMatchEasy0_32-4       761ns ± 0%     750ns ± 0%  -1.47%  (p=0.000 n=26+29)
RegexpMatchEasy0_1K-4      4.33µs ± 0%    4.34µs ± 0%  +0.27%  (p=0.000 n=25+28)
RegexpMatchEasy1_32-4       809ns ± 0%     795ns ± 0%  -1.74%  (p=0.000 n=27+25)
RegexpMatchEasy1_1K-4      5.54µs ± 0%    5.53µs ± 0%  -0.18%  (p=0.000 n=29+29)
RegexpMatchMedium_32-4     1.11µs ± 0%    1.08µs ± 0%  -2.78%  (p=0.000 n=27+29)
RegexpMatchMedium_1K-4      255µs ± 0%     255µs ± 0%  -0.02%  (p=0.029 n=30+30)
RegexpMatchHard_32-4       14.7µs ± 0%    14.7µs ± 0%  -0.28%  (p=0.000 n=30+29)
RegexpMatchHard_1K-4        439µs ± 0%     439µs ± 0%    ~     (p=0.907 n=23+27)
Revcomp-4                  41.9ms ± 1%    41.9ms ± 1%    ~     (p=0.230 n=28+30)
Template-4                  522ms ± 1%     528ms ± 1%  +1.25%  (p=0.000 n=30+30)
TimeParse-4                3.34µs ± 0%    3.35µs ± 0%  +0.23%  (p=0.000 n=30+27)
TimeFormat-4               6.06µs ± 0%    6.13µs ± 0%  +1.08%  (p=0.000 n=29+29)
[Geo mean]                  384µs          382µs       -0.37%

name                     old speed      new speed      delta
GobDecode-4              14.0MB/s ± 5%  13.9MB/s ± 5%    ~     (p=0.308 n=30+30)
GobEncode-4              15.0MB/s ± 1%  14.8MB/s ± 1%  -1.22%  (p=0.000 n=29+30)
Gzip-4                   7.36MB/s ± 0%  7.46MB/s ± 0%  +1.35%  (p=0.000 n=30+30)
Gunzip-4                 62.8MB/s ± 0%  63.0MB/s ± 0%  +0.27%  (p=0.000 n=30+30)
JSONEncode-4             19.2MB/s ± 2%  19.2MB/s ± 2%    ~     (p=0.312 n=29+29)
JSONDecode-4             5.05MB/s ± 3%  5.08MB/s ± 2%    ~     (p=0.356 n=29+30)
GoParse-4                2.56MB/s ± 0%  2.57MB/s ± 0%  +0.39%  (p=0.000 n=23+27)
RegexpMatchEasy0_32-4    42.0MB/s ± 0%  42.6MB/s ± 0%  +1.50%  (p=0.000 n=26+28)
RegexpMatchEasy0_1K-4     236MB/s ± 0%   236MB/s ± 0%  -0.27%  (p=0.000 n=25+28)
RegexpMatchEasy1_32-4    39.6MB/s ± 0%  40.2MB/s ± 0%  +1.73%  (p=0.000 n=27+27)
RegexpMatchEasy1_1K-4     185MB/s ± 0%   185MB/s ± 0%  +0.18%  (p=0.000 n=29+29)
RegexpMatchMedium_32-4    900kB/s ± 0%   920kB/s ± 0%  +2.22%  (p=0.000 n=29+29)
RegexpMatchMedium_1K-4   4.02MB/s ± 0%  4.02MB/s ± 0%  +0.07%  (p=0.004 n=30+27)
RegexpMatchHard_32-4     2.17MB/s ± 0%  2.18MB/s ± 0%  +0.46%  (p=0.000 n=30+26)
RegexpMatchHard_1K-4     2.33MB/s ± 0%  2.33MB/s ± 0%    ~     (all equal)
Revcomp-4                60.6MB/s ± 1%  60.7MB/s ± 1%    ~     (p=0.207 n=28+30)
Template-4               3.72MB/s ± 1%  3.67MB/s ± 1%  -1.23%  (p=0.000 n=30+30)
[Geo mean]               12.9MB/s       12.9MB/s       +0.29%

Change-Id: I07f497f8bb476c950dc555491d00c9066fb64a4e
Reviewed-on: https://go-review.googlesource.com/134232
Run-TryBot: Ben Shi <powerman1st@163.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
 2018-09-11 14:37:51 +00:00
erifan01
204cc14bdd cmd/compile: implement non-constant rotates using ROR on arm64 
Add some rules to match the Go code like:
	y &= 63
	x << y | x >> (64-y)
or
	y &= 63
	x >> y | x << (64-y)
as a ROR instruction. Make math/bits.RotateLeft faster on arm64.

Extends CL 132435 to arm64.

Benchmarks of math/bits.RotateLeftxxN:
name            old time/op       new time/op       delta
RotateLeft-8    3.548750ns +- 1%  2.003750ns +- 0%  -43.54%  (p=0.000 n=8+8)
RotateLeft8-8   3.925000ns +- 0%  3.925000ns +- 0%     ~     (p=1.000 n=8+8)
RotateLeft16-8  3.925000ns +- 0%  3.927500ns +- 0%     ~     (p=0.608 n=8+8)
RotateLeft32-8  3.925000ns +- 0%  2.002500ns +- 0%  -48.98%  (p=0.000 n=8+8)
RotateLeft64-8  3.536250ns +- 0%  2.003750ns +- 0%  -43.34%  (p=0.000 n=8+8)

Change-Id: I77622cd7f39b917427e060647321f5513973232c
Reviewed-on: https://go-review.googlesource.com/122542
Run-TryBot: Ben Shi <powerman1st@163.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
 2018-09-07 14:52:02 +00:00
Ben Shi
031a35ec84 cmd/compile: optimize 386's comparison 
Optimization of "(CMPconst [0] (ANDL x y)) -> (TESTL x y)" only
get benefits if there is no further use of the result of x&y. A
condition of uses==1 will have slight improvements.

1. The code size of pkg/linux_386 decreases about 300 bytes, excluding
cmd/compile/.

2. The go1 benchmark shows no regression, and even a slight improvement
in test case FmtFprintfEmpty-4, excluding noise.

name                     old time/op    new time/op    delta
BinaryTree17-4              3.34s ± 3%     3.32s ± 2%    ~     (p=0.197 n=30+30)
Fannkuch11-4                3.48s ± 2%     3.47s ± 1%  -0.33%  (p=0.015 n=30+30)
FmtFprintfEmpty-4          46.3ns ± 4%    44.8ns ± 4%  -3.33%  (p=0.000 n=30+30)
FmtFprintfString-4         78.8ns ± 7%    77.3ns ± 5%    ~     (p=0.098 n=30+26)
FmtFprintfInt-4            90.2ns ± 1%    90.0ns ± 7%  -0.23%  (p=0.027 n=18+30)
FmtFprintfIntInt-4          144ns ± 4%     143ns ± 5%    ~     (p=0.945 n=30+29)
FmtFprintfPrefixedInt-4     180ns ± 4%     180ns ± 5%    ~     (p=0.858 n=30+30)
FmtFprintfFloat-4           409ns ± 4%     406ns ± 3%  -0.87%  (p=0.028 n=30+30)
FmtManyArgs-4               611ns ± 5%     608ns ± 4%    ~     (p=0.812 n=30+30)
GobDecode-4                7.30ms ± 5%    7.26ms ± 5%    ~     (p=0.522 n=30+29)
GobEncode-4                6.90ms ± 7%    6.82ms ± 4%    ~     (p=0.086 n=29+28)
Gzip-4                      396ms ± 4%     400ms ± 4%  +0.99%  (p=0.026 n=30+30)
Gunzip-4                   41.1ms ± 3%    41.2ms ± 3%    ~     (p=0.495 n=30+30)
HTTPClientServer-4         63.7µs ± 3%    63.3µs ± 2%    ~     (p=0.113 n=29+29)
JSONEncode-4               16.1ms ± 2%    16.1ms ± 2%  -0.30%  (p=0.041 n=30+30)
JSONDecode-4               60.9ms ± 3%    61.2ms ± 6%    ~     (p=0.187 n=30+30)
Mandelbrot200-4            5.17ms ± 2%    5.19ms ± 3%    ~     (p=0.676 n=30+30)
GoParse-4                  3.28ms ± 3%    3.25ms ± 2%  -0.97%  (p=0.002 n=30+30)
RegexpMatchEasy0_32-4       103ns ± 4%     104ns ± 4%    ~     (p=0.352 n=30+30)
RegexpMatchEasy0_1K-4       849ns ± 2%     845ns ± 2%    ~     (p=0.381 n=30+30)
RegexpMatchEasy1_32-4       113ns ± 4%     113ns ± 4%    ~     (p=0.795 n=30+30)
RegexpMatchEasy1_1K-4      1.03µs ± 3%    1.03µs ± 4%    ~     (p=0.275 n=25+30)
RegexpMatchMedium_32-4      132ns ± 3%     132ns ± 3%    ~     (p=0.970 n=30+30)
RegexpMatchMedium_1K-4     41.4µs ± 3%    41.4µs ± 3%    ~     (p=0.212 n=30+30)
RegexpMatchHard_32-4       2.22µs ± 4%    2.22µs ± 4%    ~     (p=0.399 n=30+30)
RegexpMatchHard_1K-4       67.2µs ± 3%    67.6µs ± 4%    ~     (p=0.359 n=30+30)
Revcomp-4                   1.84s ± 2%     1.83s ± 2%    ~     (p=0.532 n=30+30)
Template-4                 69.1ms ± 4%    68.8ms ± 3%    ~     (p=0.146 n=30+30)
TimeParse-4                 441ns ± 3%     442ns ± 3%    ~     (p=0.154 n=30+30)
TimeFormat-4                413ns ± 3%     414ns ± 3%    ~     (p=0.275 n=30+30)
[Geo mean]                 66.2µs         66.0µs       -0.28%

name                     old speed      new speed      delta
GobDecode-4               105MB/s ± 5%   106MB/s ± 5%    ~     (p=0.514 n=30+29)
GobEncode-4               111MB/s ± 5%   113MB/s ± 4%  +1.37%  (p=0.046 n=28+28)
Gzip-4                   49.1MB/s ± 4%  48.6MB/s ± 4%  -0.98%  (p=0.028 n=30+30)
Gunzip-4                  472MB/s ± 4%   472MB/s ± 3%    ~     (p=0.496 n=30+30)
JSONEncode-4              120MB/s ± 2%   121MB/s ± 2%  +0.29%  (p=0.042 n=30+30)
JSONDecode-4             31.9MB/s ± 3%  31.7MB/s ± 6%    ~     (p=0.186 n=30+30)
GoParse-4                17.6MB/s ± 3%  17.8MB/s ± 2%  +0.98%  (p=0.002 n=30+30)
RegexpMatchEasy0_32-4     309MB/s ± 4%   307MB/s ± 4%    ~     (p=0.501 n=30+30)
RegexpMatchEasy0_1K-4    1.21GB/s ± 2%  1.21GB/s ± 2%    ~     (p=0.301 n=30+30)
RegexpMatchEasy1_32-4     283MB/s ± 4%   282MB/s ± 3%    ~     (p=0.877 n=30+30)
RegexpMatchEasy1_1K-4    1.00GB/s ± 3%  0.99GB/s ± 4%    ~     (p=0.276 n=25+30)
RegexpMatchMedium_32-4   7.54MB/s ± 3%  7.55MB/s ± 3%    ~     (p=0.528 n=30+30)
RegexpMatchMedium_1K-4   24.7MB/s ± 3%  24.7MB/s ± 3%    ~     (p=0.203 n=30+30)
RegexpMatchHard_32-4     14.4MB/s ± 4%  14.4MB/s ± 4%    ~     (p=0.407 n=30+30)
RegexpMatchHard_1K-4     15.3MB/s ± 3%  15.1MB/s ± 4%    ~     (p=0.306 n=30+30)
Revcomp-4                 138MB/s ± 2%   139MB/s ± 2%    ~     (p=0.520 n=30+30)
Template-4               28.1MB/s ± 4%  28.2MB/s ± 3%    ~     (p=0.149 n=30+30)
[Geo mean]               81.5MB/s       81.5MB/s       +0.06%

Change-Id: I7f75425f79eec93cdd8fdd94db13ad4f61b6a2f5
Reviewed-on: https://go-review.googlesource.com/133657
Run-TryBot: Ben Shi <powerman1st@163.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
 2018-09-07 01:20:45 +00:00
fanzha02
2e5c32518c cmd/compile: optimize math.Copysign on arm64 
Add rewrite rules to optimize math.Copysign() when the second
argument is negative floating point constant.

For example, math.Copysign(c, -2): The previous compile output is
"AND $9223372036854775807, R0, R0; ORR $-9223372036854775808, R0, R0".
The optimized compile output is "ORR $-9223372036854775808, R0, R0"

Math package benchmark results.
name                   old time/op  new time/op  delta
Copysign-8             2.61ns ± 2%  2.49ns ± 0%  -4.55%  (p=0.000 n=10+10)
Cos-8                  43.0ns ± 0%  41.5ns ± 0%  -3.49%  (p=0.000 n=10+10)
Cosh-8                 98.6ns ± 0%  98.1ns ± 0%  -0.51%  (p=0.000 n=10+10)
ExpGo-8                 107ns ± 0%   105ns ± 0%  -1.87%  (p=0.000 n=10+10)
Exp2Go-8                100ns ± 0%   100ns ± 0%  +0.39%  (p=0.000 n=10+8)
Max-8                  6.56ns ± 2%  6.45ns ± 1%  -1.63%  (p=0.002 n=10+10)
Min-8                  6.66ns ± 3%  6.47ns ± 2%  -2.82%  (p=0.006 n=10+10)
Mod-8                   107ns ± 1%   104ns ± 1%  -2.72%  (p=0.000 n=10+10)
Frexp-8                11.5ns ± 1%  11.0ns ± 0%  -4.56%  (p=0.000 n=8+10)
HypotGo-8              19.4ns ± 0%  19.4ns ± 0%  +0.36%  (p=0.019 n=10+10)
Ilogb-8                8.63ns ± 0%  8.51ns ± 0%  -1.36%  (p=0.000 n=10+10)
Jn-8                    584ns ± 0%   585ns ± 0%  +0.17%  (p=0.000 n=7+8)
Ldexp-8                13.8ns ± 0%  13.5ns ± 0%  -2.17%  (p=0.002 n=8+10)
Logb-8                 10.2ns ± 0%   9.9ns ± 0%  -2.65%  (p=0.000 n=10+7)
Nextafter64-8          7.54ns ± 0%  7.51ns ± 0%  -0.37%  (p=0.000 n=10+10)
Remainder-8            73.5ns ± 1%  70.4ns ± 1%  -4.27%  (p=0.000 n=10+10)
SqrtGoLatency-8        79.6ns ± 0%  76.2ns ± 0%  -4.30%  (p=0.000 n=9+10)
Yn-8                    582ns ± 0%   579ns ± 0%  -0.52%  (p=0.000 n=10+10)

Change-Id: I0c9cd1ea87435e7b8bab94b4e79e6e29785f25b1
Reviewed-on: https://go-review.googlesource.com/132915
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
 2018-09-06 19:57:25 +00:00
Ben Shi
067dfce21f cmd/compile: optimize ARM's comparision 
Optimize (CMPconst [0] (ADD x y)) to (CMN x y) will only get benefits
when the result of the addition is no longer used, otherwise there
might be even performance drop. And this CL fixes that issue for
CMP/CMN/TST/TEQ.

There is little regression in the go1 benchmark (excluding noise),
and the test case JSONDecode-4 even gets improvement.

name                     old time/op    new time/op    delta
BinaryTree17-4              21.6s ± 1%     21.6s ± 0%  -0.22%  (p=0.013 n=30+30)
Fannkuch11-4                11.1s ± 0%     11.1s ± 0%  +0.11%  (p=0.000 n=30+29)
FmtFprintfEmpty-4           297ns ± 0%     297ns ± 0%  +0.08%  (p=0.007 n=26+28)
FmtFprintfString-4          589ns ± 1%     589ns ± 0%    ~     (p=0.659 n=30+25)
FmtFprintfInt-4             644ns ± 1%     650ns ± 0%  +0.88%  (p=0.000 n=30+24)
FmtFprintfIntInt-4          964ns ± 0%     977ns ± 0%  +1.33%  (p=0.000 n=30+30)
FmtFprintfPrefixedInt-4    1.06µs ± 0%    1.07µs ± 0%  +1.31%  (p=0.000 n=29+27)
FmtFprintfFloat-4          1.89µs ± 0%    1.92µs ± 0%  +1.25%  (p=0.000 n=29+29)
FmtManyArgs-4              3.63µs ± 0%    3.67µs ± 0%  +1.33%  (p=0.000 n=29+27)
GobDecode-4                38.1ms ± 1%    37.9ms ± 1%  -0.60%  (p=0.000 n=29+29)
GobEncode-4                35.3ms ± 2%    35.2ms ± 1%    ~     (p=0.286 n=30+30)
Gzip-4                      2.36s ± 0%     2.37s ± 2%    ~     (p=0.277 n=24+28)
Gunzip-4                    264ms ± 1%     264ms ± 1%    ~     (p=0.104 n=28+30)
HTTPClientServer-4         1.04ms ± 4%    1.02ms ± 4%  -1.65%  (p=0.000 n=28+28)
JSONEncode-4               78.5ms ± 1%    79.6ms ± 1%  +1.34%  (p=0.000 n=27+28)
JSONDecode-4                379ms ± 4%     352ms ± 5%  -7.09%  (p=0.000 n=29+30)
Mandelbrot200-4            17.6ms ± 0%    17.6ms ± 0%    ~     (p=0.206 n=28+29)
GoParse-4                  21.9ms ± 1%    22.1ms ± 1%  +0.87%  (p=0.000 n=28+26)
RegexpMatchEasy0_32-4       631ns ± 0%     641ns ± 0%  +1.63%  (p=0.000 n=29+30)
RegexpMatchEasy0_1K-4      4.11µs ± 0%    4.11µs ± 0%    ~     (p=0.700 n=30+30)
RegexpMatchEasy1_32-4       670ns ± 0%     679ns ± 0%  +1.37%  (p=0.000 n=21+30)
RegexpMatchEasy1_1K-4      5.31µs ± 0%    5.26µs ± 0%  -1.03%  (p=0.000 n=25+28)
RegexpMatchMedium_32-4      905ns ± 0%     906ns ± 0%  +0.14%  (p=0.001 n=30+30)
RegexpMatchMedium_1K-4      192µs ± 0%     191µs ± 0%  -0.45%  (p=0.000 n=29+27)
RegexpMatchHard_32-4       11.8µs ± 0%    11.7µs ± 0%  -0.39%  (p=0.000 n=29+28)
RegexpMatchHard_1K-4        347µs ± 0%     347µs ± 0%    ~     (p=0.084 n=29+30)
Revcomp-4                  37.5ms ± 1%    37.5ms ± 1%    ~     (p=0.279 n=29+29)
Template-4                  519ms ± 2%     519ms ± 2%    ~     (p=0.652 n=28+29)
TimeParse-4                2.83µs ± 0%    2.78µs ± 0%  -1.90%  (p=0.000 n=27+28)
TimeFormat-4               5.79µs ± 0%    5.60µs ± 0%  -3.23%  (p=0.000 n=29+29)
[Geo mean]                  331µs          330µs       -0.16%

name                     old speed      new speed      delta
GobDecode-4              20.1MB/s ± 1%  20.3MB/s ± 1%  +0.61%  (p=0.000 n=29+29)
GobEncode-4              21.7MB/s ± 2%  21.8MB/s ± 1%    ~     (p=0.294 n=30+30)
Gzip-4                   8.23MB/s ± 1%  8.20MB/s ± 2%    ~     (p=0.099 n=26+28)
Gunzip-4                 73.5MB/s ± 1%  73.4MB/s ± 1%    ~     (p=0.107 n=28+30)
JSONEncode-4             24.7MB/s ± 1%  24.4MB/s ± 1%  -1.32%  (p=0.000 n=27+28)
JSONDecode-4             5.13MB/s ± 4%  5.52MB/s ± 5%  +7.65%  (p=0.000 n=29+30)
GoParse-4                2.65MB/s ± 1%  2.63MB/s ± 1%  -0.87%  (p=0.000 n=28+26)
RegexpMatchEasy0_32-4    50.7MB/s ± 0%  49.9MB/s ± 0%  -1.58%  (p=0.000 n=29+29)
RegexpMatchEasy0_1K-4     249MB/s ± 0%   249MB/s ± 0%    ~     (p=0.342 n=30+28)
RegexpMatchEasy1_32-4    47.7MB/s ± 0%  47.1MB/s ± 0%  -1.39%  (p=0.000 n=26+30)
RegexpMatchEasy1_1K-4     193MB/s ± 0%   195MB/s ± 0%  +1.04%  (p=0.000 n=25+28)
RegexpMatchMedium_32-4   1.10MB/s ± 0%  1.10MB/s ± 0%  -0.42%  (p=0.000 n=30+26)
RegexpMatchMedium_1K-4   5.33MB/s ± 0%  5.36MB/s ± 0%  +0.43%  (p=0.000 n=29+29)
RegexpMatchHard_32-4     2.72MB/s ± 0%  2.73MB/s ± 0%  +0.37%  (p=0.000 n=29+30)
RegexpMatchHard_1K-4     2.95MB/s ± 0%  2.95MB/s ± 0%    ~     (all equal)
Revcomp-4                67.8MB/s ± 1%  67.7MB/s ± 1%    ~     (p=0.273 n=29+29)
Template-4               3.74MB/s ± 2%  3.74MB/s ± 2%    ~     (p=0.665 n=28+29)
[Geo mean]               15.2MB/s       15.2MB/s       +0.21%

Change-Id: Ifed1fb8cc02d5ca52c8bc6c21b6b5bf6dbb2701a
Reviewed-on: https://go-review.googlesource.com/132115
Run-TryBot: Ben Shi <powerman1st@163.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
 2018-09-05 14:54:08 +00:00
Michael Munday
f94de9c9fb cmd/compile: make math/bits.RotateLeft{32,64} intrinsics on s390x 
Extends CL 132435 to s390x. s390x has 32- and 64-bit variable
rotate left instructions.

Change-Id: Ic4f1ebb0e0543207ed2fc8c119e0163b428138a5
Reviewed-on: https://go-review.googlesource.com/133035
Run-TryBot: Michael Munday <mike.munday@ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
 2018-09-05 08:29:02 +00:00
Ben Shi
0e9f1de0b7 cmd/compile: optimize arm64's comparison 
Add more optimization with TST/CMN.

1. A tiny benchmark shows more than 12% improvement.
TSTCMN-4                    378µs ± 0%     332µs ± 0%  -12.15%  (p=0.000 n=30+27)
(https://github.com/benshi001/ugo1/blob/master/tstcmn_test.go)

2. There is little regression in the go1 benchmark, excluding noise.

name                     old time/op    new time/op    delta
BinaryTree17-4              19.1s ± 0%     19.1s ± 0%    ~     (p=0.994 n=28+29)
Fannkuch11-4                10.0s ± 0%     10.0s ± 0%    ~     (p=0.198 n=30+25)
FmtFprintfEmpty-4           233ns ± 0%     233ns ± 0%  +0.14%  (p=0.002 n=24+30)
FmtFprintfString-4          428ns ± 0%     428ns ± 0%    ~     (all equal)
FmtFprintfInt-4             472ns ± 0%     472ns ± 0%    ~     (all equal)
FmtFprintfIntInt-4          725ns ± 0%     725ns ± 0%    ~     (all equal)
FmtFprintfPrefixedInt-4     889ns ± 0%     888ns ± 0%    ~     (p=0.632 n=28+30)
FmtFprintfFloat-4          1.20µs ± 0%    1.20µs ± 0%  +0.05%  (p=0.001 n=18+30)
FmtManyArgs-4              3.00µs ± 0%    2.99µs ± 0%  -0.07%  (p=0.001 n=27+30)
GobDecode-4                42.1ms ± 0%    42.2ms ± 0%  +0.29%  (p=0.000 n=28+28)
GobEncode-4                38.6ms ± 9%    38.8ms ± 9%    ~     (p=0.912 n=30+30)
Gzip-4                      2.07s ± 1%     2.05s ± 1%  -0.64%  (p=0.000 n=29+30)
Gunzip-4                    175ms ± 0%     175ms ± 0%  -0.15%  (p=0.001 n=30+30)
HTTPClientServer-4          872µs ± 5%     880µs ± 6%    ~     (p=0.196 n=30+29)
JSONEncode-4               88.5ms ± 1%    89.8ms ± 1%  +1.49%  (p=0.000 n=23+24)
JSONDecode-4                393ms ± 1%     390ms ± 1%  -0.89%  (p=0.000 n=28+30)
Mandelbrot200-4            19.5ms ± 0%    19.5ms ± 0%    ~     (p=0.405 n=29+28)
GoParse-4                  19.9ms ± 0%    20.0ms ± 0%  +0.27%  (p=0.000 n=30+30)
RegexpMatchEasy0_32-4       431ns ± 0%     431ns ± 0%    ~     (p=1.000 n=30+30)
RegexpMatchEasy0_1K-4      1.61µs ± 0%    1.61µs ± 0%    ~     (p=0.527 n=26+26)
RegexpMatchEasy1_32-4       443ns ± 0%     443ns ± 0%    ~     (all equal)
RegexpMatchEasy1_1K-4      2.58µs ± 1%    2.58µs ± 1%    ~     (p=0.578 n=27+25)
RegexpMatchMedium_32-4      740ns ± 0%     740ns ± 0%    ~     (p=0.357 n=30+30)
RegexpMatchMedium_1K-4      223µs ± 0%     223µs ± 0%  +0.16%  (p=0.000 n=30+29)
RegexpMatchHard_32-4       12.3µs ± 0%    12.3µs ± 0%    ~     (p=0.236 n=27+27)
RegexpMatchHard_1K-4        371µs ± 0%     371µs ± 0%  +0.09%  (p=0.000 n=30+27)
Revcomp-4                   2.85s ± 0%     2.85s ± 0%    ~     (p=0.057 n=28+25)
Template-4                  408ms ± 1%     409ms ± 1%    ~     (p=0.117 n=29+29)
TimeParse-4                1.93µs ± 0%    1.93µs ± 0%    ~     (p=0.535 n=29+28)
TimeFormat-4               1.99µs ± 0%    1.99µs ± 0%    ~     (p=0.168 n=29+28)
[Geo mean]                  306µs          307µs       +0.07%

name                     old speed      new speed      delta
GobDecode-4              18.3MB/s ± 0%  18.2MB/s ± 0%  -0.31%  (p=0.000 n=28+29)
GobEncode-4              19.9MB/s ± 8%  19.8MB/s ± 9%    ~     (p=0.923 n=30+30)
Gzip-4                   9.39MB/s ± 1%  9.45MB/s ± 1%  +0.65%  (p=0.000 n=29+30)
Gunzip-4                  111MB/s ± 0%   111MB/s ± 0%  +0.15%  (p=0.001 n=30+30)
JSONEncode-4             21.9MB/s ± 1%  21.6MB/s ± 1%  -1.45%  (p=0.000 n=23+23)
JSONDecode-4             4.94MB/s ± 1%  4.98MB/s ± 1%  +0.84%  (p=0.000 n=27+30)
GoParse-4                2.91MB/s ± 0%  2.90MB/s ± 0%  -0.34%  (p=0.000 n=21+22)
RegexpMatchEasy0_32-4    74.1MB/s ± 0%  74.1MB/s ± 0%    ~     (p=0.469 n=29+28)
RegexpMatchEasy0_1K-4     634MB/s ± 0%   634MB/s ± 0%    ~     (p=0.978 n=24+28)
RegexpMatchEasy1_32-4    72.2MB/s ± 0%  72.2MB/s ± 0%    ~     (p=0.064 n=27+29)
RegexpMatchEasy1_1K-4     396MB/s ± 1%   396MB/s ± 1%    ~     (p=0.583 n=27+25)
RegexpMatchMedium_32-4   1.35MB/s ± 0%  1.35MB/s ± 0%    ~     (all equal)
RegexpMatchMedium_1K-4   4.60MB/s ± 0%  4.59MB/s ± 0%  -0.14%  (p=0.000 n=30+26)
RegexpMatchHard_32-4     2.61MB/s ± 0%  2.61MB/s ± 0%    ~     (all equal)
RegexpMatchHard_1K-4     2.76MB/s ± 0%  2.76MB/s ± 0%    ~     (all equal)
Revcomp-4                89.1MB/s ± 0%  89.1MB/s ± 0%    ~     (p=0.059 n=28+25)
Template-4               4.75MB/s ± 1%  4.75MB/s ± 1%    ~     (p=0.106 n=29+29)
[Geo mean]               18.3MB/s       18.3MB/s       -0.07%

Change-Id: I3cd76ce63e84b0c3cebabf9fa3573b76a7343899
Reviewed-on: https://go-review.googlesource.com/124935
Run-TryBot: Ben Shi <powerman1st@163.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
 2018-09-05 02:51:28 +00:00
Ben Shi
b444215116 cmd/compile: optimize ARM64's code with MADD/MSUB 
MADD does MUL-ADD in a single instruction, and MSUB does the
similiar simplification for MUL-SUB.

The CL implements the optimization with MADD/MSUB.

1. The total size of pkg/android_arm64/ decreases about 20KB,
excluding cmd/compile/.

2. The go1 benchmark shows a little improvement for RegexpMatchHard_32-4
and Template-4, excluding noise.

name                     old time/op    new time/op    delta
BinaryTree17-4              16.3s ± 1%     16.5s ± 1%  +1.41%  (p=0.000 n=26+28)
Fannkuch11-4                8.79s ± 1%     8.76s ± 0%  -0.36%  (p=0.000 n=26+28)
FmtFprintfEmpty-4           172ns ± 0%     172ns ± 0%    ~     (all equal)
FmtFprintfString-4          362ns ± 1%     364ns ± 0%  +0.55%  (p=0.000 n=30+30)
FmtFprintfInt-4             416ns ± 0%     416ns ± 0%    ~     (p=0.099 n=22+30)
FmtFprintfIntInt-4          655ns ± 1%     660ns ± 1%  +0.76%  (p=0.000 n=30+30)
FmtFprintfPrefixedInt-4     810ns ± 0%     809ns ± 0%  -0.08%  (p=0.009 n=29+29)
FmtFprintfFloat-4          1.08µs ± 0%    1.09µs ± 0%  +0.61%  (p=0.000 n=30+29)
FmtManyArgs-4              2.70µs ± 0%    2.69µs ± 0%  -0.23%  (p=0.000 n=29+28)
GobDecode-4                32.2ms ± 1%    32.1ms ± 1%  -0.39%  (p=0.000 n=27+26)
GobEncode-4                27.4ms ± 2%    27.4ms ± 1%    ~     (p=0.864 n=28+28)
Gzip-4                      1.53s ± 1%     1.52s ± 1%  -0.30%  (p=0.031 n=29+29)
Gunzip-4                    146ms ± 0%     146ms ± 0%  -0.14%  (p=0.001 n=25+30)
HTTPClientServer-4         1.00ms ± 4%    0.98ms ± 6%  -1.65%  (p=0.001 n=29+30)
JSONEncode-4               67.3ms ± 1%    67.2ms ± 1%    ~     (p=0.520 n=28+28)
JSONDecode-4                329ms ± 5%     330ms ± 4%    ~     (p=0.142 n=30+30)
Mandelbrot200-4            17.3ms ± 0%    17.3ms ± 0%    ~     (p=0.055 n=26+29)
GoParse-4                  16.9ms ± 1%    17.0ms ± 1%  +0.82%  (p=0.000 n=30+30)
RegexpMatchEasy0_32-4       382ns ± 0%     382ns ± 0%    ~     (all equal)
RegexpMatchEasy0_1K-4      1.33µs ± 0%    1.33µs ± 0%  -0.25%  (p=0.000 n=30+27)
RegexpMatchEasy1_32-4       361ns ± 0%     361ns ± 0%  -0.08%  (p=0.002 n=30+28)
RegexpMatchEasy1_1K-4      2.11µs ± 0%    2.09µs ± 0%  -0.54%  (p=0.000 n=30+29)
RegexpMatchMedium_32-4      594ns ± 0%     592ns ± 0%  -0.32%  (p=0.000 n=30+30)
RegexpMatchMedium_1K-4      173µs ± 0%     172µs ± 0%  -0.77%  (p=0.000 n=29+27)
RegexpMatchHard_32-4       10.4µs ± 0%    10.1µs ± 0%  -3.63%  (p=0.000 n=28+27)
RegexpMatchHard_1K-4        306µs ± 0%     301µs ± 0%  -1.64%  (p=0.000 n=29+30)
Revcomp-4                   2.51s ± 1%     2.52s ± 0%  +0.18%  (p=0.017 n=26+27)
Template-4                  394ms ± 3%     382ms ± 3%  -3.22%  (p=0.000 n=28+28)
TimeParse-4                1.67µs ± 0%    1.67µs ± 0%  +0.05%  (p=0.030 n=27+30)
TimeFormat-4               1.72µs ± 0%    1.70µs ± 0%  -0.79%  (p=0.000 n=28+26)
[Geo mean]                  259µs          259µs       -0.33%

name                     old speed      new speed      delta
GobDecode-4              23.8MB/s ± 1%  23.9MB/s ± 1%  +0.40%  (p=0.001 n=27+26)
GobEncode-4              28.0MB/s ± 2%  28.0MB/s ± 1%    ~     (p=0.863 n=28+28)
Gzip-4                   12.7MB/s ± 1%  12.7MB/s ± 1%  +0.32%  (p=0.026 n=29+29)
Gunzip-4                  133MB/s ± 0%   133MB/s ± 0%  +0.15%  (p=0.001 n=24+30)
JSONEncode-4             28.8MB/s ± 1%  28.9MB/s ± 1%    ~     (p=0.475 n=28+28)
JSONDecode-4             5.89MB/s ± 4%  5.87MB/s ± 5%    ~     (p=0.174 n=29+30)
GoParse-4                3.43MB/s ± 0%  3.40MB/s ± 1%  -0.83%  (p=0.000 n=28+30)
RegexpMatchEasy0_32-4    83.6MB/s ± 0%  83.6MB/s ± 0%    ~     (p=0.848 n=28+29)
RegexpMatchEasy0_1K-4     768MB/s ± 0%   770MB/s ± 0%  +0.25%  (p=0.000 n=30+27)
RegexpMatchEasy1_32-4    88.5MB/s ± 0%  88.5MB/s ± 0%    ~     (p=0.086 n=29+29)
RegexpMatchEasy1_1K-4     486MB/s ± 0%   489MB/s ± 0%  +0.54%  (p=0.000 n=30+29)
RegexpMatchMedium_32-4   1.68MB/s ± 0%  1.69MB/s ± 0%  +0.60%  (p=0.000 n=30+23)
RegexpMatchMedium_1K-4   5.90MB/s ± 0%  5.95MB/s ± 0%  +0.85%  (p=0.000 n=18+20)
RegexpMatchHard_32-4     3.07MB/s ± 0%  3.18MB/s ± 0%  +3.72%  (p=0.000 n=29+26)
RegexpMatchHard_1K-4     3.35MB/s ± 0%  3.40MB/s ± 0%  +1.69%  (p=0.000 n=30+30)
Revcomp-4                 101MB/s ± 0%   101MB/s ± 0%  -0.18%  (p=0.018 n=26+27)
Template-4               4.92MB/s ± 4%  5.09MB/s ± 3%  +3.31%  (p=0.000 n=28+28)
[Geo mean]               22.4MB/s       22.6MB/s       +0.62%

Change-Id: I8f304b272785739f57b3c8f736316f658f8c1b2a
Reviewed-on: https://go-review.googlesource.com/129119
Run-TryBot: Ben Shi <powerman1st@163.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
 2018-09-04 20:41:58 +00:00
Michael Munday
6f9b94ab66 cmd/compile: implement OnesCount{8,16,32,64} intrinsics on s390x 
This CL implements the math/bits.OnesCount{8,16,32,64} functions
as intrinsics on s390x using the 'population count' (popcnt)
instruction. This instruction was released as the 'population-count'
facility which uses the same facility bit (45) as the
'distinct-operands' facility which is a pre-requisite for Go on
s390x. We can therefore use it without a feature check.

The s390x popcnt instruction treats a 64 bit register as a vector
of 8 bytes, summing the number of ones in each byte individually.
It then writes the results to the corresponding bytes in the
output register. Therefore to implement OnesCount{16,32,64} we
need to sum the individual byte counts using some extra
instructions. To do this efficiently I've added some additional
pseudo operations to the s390x SSA backend.

Unlike other architectures the new instruction sequence is faster
for OnesCount8, so that is implemented using the intrinsic.

name         old time/op  new time/op  delta
OnesCount    3.21ns ± 1%  1.35ns ± 0%  -58.00%  (p=0.000 n=20+20)
OnesCount8   0.91ns ± 1%  0.81ns ± 0%  -11.43%  (p=0.000 n=20+20)
OnesCount16  1.51ns ± 3%  1.21ns ± 0%  -19.71%  (p=0.000 n=20+17)
OnesCount32  1.91ns ± 0%  1.12ns ± 1%  -41.60%  (p=0.000 n=19+20)
OnesCount64  3.18ns ± 4%  1.35ns ± 0%  -57.52%  (p=0.000 n=20+20)

Change-Id: Id54f0bd28b6db9a887ad12c0d72fcc168ef9c4e0
Reviewed-on: https://go-review.googlesource.com/114675
Run-TryBot: Michael Munday <mike.munday@ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
 2018-09-03 14:35:38 +00:00
Giovanni Bajo
f02cc88f46 test: relax whitespaces matching in codegen tests 
The codegen testsuite uses regexp to parse the syntax, but it doesn't
have a way to tell line comments containing checks from line comments
containing English sentences. This means that any syntax error (that
is, non-matching regexp) is currently ignored and not reported.

There were some tests in memcombine.go that had an extraneous space
and were thus effectively disabled. It would be great if we could
report it as a syntax error, but for now we just punt and swallow the
spaces as a workaround, to avoid the same mistake again.

Fixes #25452

Change-Id: Ic7747a2278bc00adffd0c199ce40937acbbc9cf0
Reviewed-on: https://go-review.googlesource.com/113835
Run-TryBot: Giovanni Bajo <rasky@develer.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
 2018-09-02 10:31:37 +00:00
Zheng Xu
8f4fd3f34e build: support frame-pointer for arm64 
Supporting frame-pointer makes Linux's perf and other profilers much more useful
because it lets them gather a stack trace efficiently on profiling events. Major
changes include:
1. save FP on the word below where RSP is pointing to (proposed by Cherry and Austin)
2. adjust some specific offsets in runtime assembly and wrapper code
3. add support to FP in goroutine scheduler
4. adjust link stack overflow check to take the extra word into account
5. adjust nosplit test cases to enable frame sizes which are 16 bytes aligned

Performance impacts on go1 benchmarks:

Enable frame-pointer (by default)

name                      old time/op    new time/op    delta
BinaryTree17-46              5.94s ± 0%     6.00s ± 0%  +1.03%  (p=0.029 n=4+4)
Fannkuch11-46                2.84s ± 1%     2.77s ± 0%  -2.58%  (p=0.008 n=5+5)
FmtFprintfEmpty-46          55.0ns ± 1%    58.9ns ± 1%  +7.06%  (p=0.008 n=5+5)
FmtFprintfString-46          102ns ± 0%     105ns ± 0%  +2.94%  (p=0.008 n=5+5)
FmtFprintfInt-46             118ns ± 0%     117ns ± 1%  -1.19%  (p=0.000 n=4+5)
FmtFprintfIntInt-46          181ns ± 0%     182ns ± 1%    ~     (p=0.444 n=5+5)
FmtFprintfPrefixedInt-46     215ns ± 1%     214ns ± 0%    ~     (p=0.254 n=5+4)
FmtFprintfFloat-46           292ns ± 0%     296ns ± 0%  +1.46%  (p=0.029 n=4+4)
FmtManyArgs-46               720ns ± 0%     732ns ± 0%  +1.72%  (p=0.008 n=5+5)
GobDecode-46                9.82ms ± 1%   10.03ms ± 2%  +2.10%  (p=0.008 n=5+5)
GobEncode-46                8.14ms ± 0%    8.72ms ± 1%  +7.14%  (p=0.008 n=5+5)
Gzip-46                      420ms ± 0%     424ms ± 0%  +0.92%  (p=0.008 n=5+5)
Gunzip-46                   48.2ms ± 0%    48.4ms ± 0%  +0.41%  (p=0.008 n=5+5)
HTTPClientServer-46          201µs ± 4%     201µs ± 0%    ~     (p=0.730 n=5+4)
JSONEncode-46               17.1ms ± 0%    17.7ms ± 1%  +3.80%  (p=0.008 n=5+5)
JSONDecode-46               88.0ms ± 0%    90.1ms ± 0%  +2.42%  (p=0.008 n=5+5)
Mandelbrot200-46            5.06ms ± 0%    5.07ms ± 0%    ~     (p=0.310 n=5+5)
GoParse-46                  5.04ms ± 0%    5.12ms ± 0%  +1.53%  (p=0.008 n=5+5)
RegexpMatchEasy0_32-46       117ns ± 0%     117ns ± 0%    ~     (all equal)
RegexpMatchEasy0_1K-46       332ns ± 0%     329ns ± 0%  -0.78%  (p=0.008 n=5+5)
RegexpMatchEasy1_32-46       104ns ± 0%     113ns ± 0%  +8.65%  (p=0.029 n=4+4)
RegexpMatchEasy1_1K-46       563ns ± 0%     569ns ± 0%  +1.10%  (p=0.008 n=5+5)
RegexpMatchMedium_32-46      167ns ± 2%     177ns ± 1%  +5.74%  (p=0.008 n=5+5)
RegexpMatchMedium_1K-46     49.5µs ± 0%    53.4µs ± 0%  +7.81%  (p=0.008 n=5+5)
RegexpMatchHard_32-46       2.56µs ± 1%    2.72µs ± 0%  +6.01%  (p=0.008 n=5+5)
RegexpMatchHard_1K-46       77.0µs ± 0%    81.8µs ± 0%  +6.24%  (p=0.016 n=5+4)
Revcomp-46                   631ms ± 1%     627ms ± 1%    ~     (p=0.095 n=5+5)
Template-46                 81.8ms ± 0%    86.3ms ± 0%  +5.55%  (p=0.008 n=5+5)
TimeParse-46                 423ns ± 0%     432ns ± 0%  +2.32%  (p=0.008 n=5+5)
TimeFormat-46                478ns ± 2%     497ns ± 1%  +3.89%  (p=0.008 n=5+5)
[Geo mean]                  71.6µs         73.3µs       +2.45%

name                      old speed      new speed      delta
GobDecode-46              78.1MB/s ± 1%  76.6MB/s ± 2%  -2.04%  (p=0.008 n=5+5)
GobEncode-46              94.3MB/s ± 0%  88.0MB/s ± 1%  -6.67%  (p=0.008 n=5+5)
Gzip-46                   46.2MB/s ± 0%  45.8MB/s ± 0%  -0.91%  (p=0.008 n=5+5)
Gunzip-46                  403MB/s ± 0%   401MB/s ± 0%  -0.41%  (p=0.008 n=5+5)
JSONEncode-46              114MB/s ± 0%   109MB/s ± 1%  -3.66%  (p=0.008 n=5+5)
JSONDecode-46             22.0MB/s ± 0%  21.5MB/s ± 0%  -2.35%  (p=0.008 n=5+5)
GoParse-46                11.5MB/s ± 0%  11.3MB/s ± 0%  -1.51%  (p=0.008 n=5+5)
RegexpMatchEasy0_32-46     272MB/s ± 0%   272MB/s ± 1%    ~     (p=0.190 n=4+5)
RegexpMatchEasy0_1K-46    3.08GB/s ± 0%  3.11GB/s ± 0%  +0.77%  (p=0.008 n=5+5)
RegexpMatchEasy1_32-46     306MB/s ± 0%   283MB/s ± 0%  -7.63%  (p=0.029 n=4+4)
RegexpMatchEasy1_1K-46    1.82GB/s ± 0%  1.80GB/s ± 0%  -1.07%  (p=0.008 n=5+5)
RegexpMatchMedium_32-46   5.99MB/s ± 0%  5.64MB/s ± 1%  -5.77%  (p=0.016 n=4+5)
RegexpMatchMedium_1K-46   20.7MB/s ± 0%  19.2MB/s ± 0%  -7.25%  (p=0.008 n=5+5)
RegexpMatchHard_32-46     12.5MB/s ± 1%  11.8MB/s ± 0%  -5.66%  (p=0.008 n=5+5)
RegexpMatchHard_1K-46     13.3MB/s ± 0%  12.5MB/s ± 1%  -6.01%  (p=0.008 n=5+5)
Revcomp-46                 402MB/s ± 1%   405MB/s ± 1%    ~     (p=0.095 n=5+5)
Template-46               23.7MB/s ± 0%  22.5MB/s ± 0%  -5.25%  (p=0.008 n=5+5)
[Geo mean]                82.2MB/s       79.6MB/s       -3.26%

Disable frame-pointer (GOEXPERIMENT=noframepointer)

name                      old time/op    new time/op    delta
BinaryTree17-46              5.94s ± 0%     5.96s ± 0%  +0.39%  (p=0.029 n=4+4)
Fannkuch11-46                2.84s ± 1%     2.79s ± 1%  -1.68%  (p=0.008 n=5+5)
FmtFprintfEmpty-46          55.0ns ± 1%    55.2ns ± 3%    ~     (p=0.794 n=5+5)
FmtFprintfString-46          102ns ± 0%     103ns ± 0%  +0.98%  (p=0.016 n=5+4)
FmtFprintfInt-46             118ns ± 0%     115ns ± 0%  -2.54%  (p=0.029 n=4+4)
FmtFprintfIntInt-46          181ns ± 0%     179ns ± 0%  -1.10%  (p=0.000 n=5+4)
FmtFprintfPrefixedInt-46     215ns ± 1%     213ns ± 0%    ~     (p=0.143 n=5+4)
FmtFprintfFloat-46           292ns ± 0%     300ns ± 0%  +2.83%  (p=0.029 n=4+4)
FmtManyArgs-46               720ns ± 0%     739ns ± 0%  +2.64%  (p=0.008 n=5+5)
GobDecode-46                9.82ms ± 1%    9.78ms ± 1%    ~     (p=0.151 n=5+5)
GobEncode-46                8.14ms ± 0%    8.12ms ± 1%    ~     (p=0.690 n=5+5)
Gzip-46                      420ms ± 0%     420ms ± 0%    ~     (p=0.548 n=5+5)
Gunzip-46                   48.2ms ± 0%    48.0ms ± 0%  -0.33%  (p=0.032 n=5+5)
HTTPClientServer-46          201µs ± 4%     199µs ± 3%    ~     (p=0.548 n=5+5)
JSONEncode-46               17.1ms ± 0%    17.2ms ± 0%    ~     (p=0.056 n=5+5)
JSONDecode-46               88.0ms ± 0%    88.6ms ± 0%  +0.64%  (p=0.008 n=5+5)
Mandelbrot200-46            5.06ms ± 0%    5.07ms ± 0%    ~     (p=0.548 n=5+5)
GoParse-46                  5.04ms ± 0%    5.07ms ± 0%  +0.65%  (p=0.008 n=5+5)
RegexpMatchEasy0_32-46       117ns ± 0%     112ns ± 4%  -4.27%  (p=0.016 n=4+5)
RegexpMatchEasy0_1K-46       332ns ± 0%     330ns ± 1%    ~     (p=0.095 n=5+5)
RegexpMatchEasy1_32-46       104ns ± 0%     110ns ± 1%  +5.29%  (p=0.029 n=4+4)
RegexpMatchEasy1_1K-46       563ns ± 0%     567ns ± 2%    ~     (p=0.151 n=5+5)
RegexpMatchMedium_32-46      167ns ± 2%     166ns ± 0%    ~     (p=0.333 n=5+4)
RegexpMatchMedium_1K-46     49.5µs ± 0%    49.6µs ± 0%    ~     (p=0.841 n=5+5)
RegexpMatchHard_32-46       2.56µs ± 1%    2.49µs ± 0%  -2.81%  (p=0.008 n=5+5)
RegexpMatchHard_1K-46       77.0µs ± 0%    75.8µs ± 0%  -1.55%  (p=0.008 n=5+5)
Revcomp-46                   631ms ± 1%     628ms ± 0%    ~     (p=0.095 n=5+5)
Template-46                 81.8ms ± 0%    84.3ms ± 1%  +3.05%  (p=0.008 n=5+5)
TimeParse-46                 423ns ± 0%     425ns ± 0%  +0.52%  (p=0.008 n=5+5)
TimeFormat-46                478ns ± 2%     478ns ± 1%    ~     (p=1.000 n=5+5)
[Geo mean]                  71.6µs         71.6µs       -0.01%

name                      old speed      new speed      delta
GobDecode-46              78.1MB/s ± 1%  78.5MB/s ± 1%    ~     (p=0.151 n=5+5)
GobEncode-46              94.3MB/s ± 0%  94.5MB/s ± 1%    ~     (p=0.690 n=5+5)
Gzip-46                   46.2MB/s ± 0%  46.2MB/s ± 0%    ~     (p=0.571 n=5+5)
Gunzip-46                  403MB/s ± 0%   404MB/s ± 0%  +0.33%  (p=0.032 n=5+5)
JSONEncode-46              114MB/s ± 0%   113MB/s ± 0%    ~     (p=0.056 n=5+5)
JSONDecode-46             22.0MB/s ± 0%  21.9MB/s ± 0%  -0.64%  (p=0.008 n=5+5)
GoParse-46                11.5MB/s ± 0%  11.4MB/s ± 0%  -0.64%  (p=0.008 n=5+5)
RegexpMatchEasy0_32-46     272MB/s ± 0%   285MB/s ± 4%  +4.74%  (p=0.016 n=4+5)
RegexpMatchEasy0_1K-46    3.08GB/s ± 0%  3.10GB/s ± 1%    ~     (p=0.151 n=5+5)
RegexpMatchEasy1_32-46     306MB/s ± 0%   290MB/s ± 1%  -5.21%  (p=0.029 n=4+4)
RegexpMatchEasy1_1K-46    1.82GB/s ± 0%  1.81GB/s ± 2%    ~     (p=0.151 n=5+5)
RegexpMatchMedium_32-46   5.99MB/s ± 0%  6.02MB/s ± 1%    ~     (p=0.063 n=4+5)
RegexpMatchMedium_1K-46   20.7MB/s ± 0%  20.7MB/s ± 0%    ~     (p=0.659 n=5+5)
RegexpMatchHard_32-46     12.5MB/s ± 1%  12.8MB/s ± 0%  +2.88%  (p=0.008 n=5+5)
RegexpMatchHard_1K-46     13.3MB/s ± 0%  13.5MB/s ± 0%  +1.58%  (p=0.008 n=5+5)
Revcomp-46                 402MB/s ± 1%   405MB/s ± 0%    ~     (p=0.095 n=5+5)
Template-46               23.7MB/s ± 0%  23.0MB/s ± 1%  -2.95%  (p=0.008 n=5+5)
[Geo mean]                82.2MB/s       82.3MB/s       +0.04%

Frame-pointer is enabled on Linux by default but can be disabled by setting: GOEXPERIMENT=noframepointer.

Fixes #10110

Change-Id: I1bfaca6dba29a63009d7c6ab04ed7a1413d9479e
Reviewed-on: https://go-review.googlesource.com/61511
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
 2018-08-29 18:28:34 +00:00
Ben Shi
3ca3e89bb6 cmd/compile: optimize arm64 with indexed FP load/store 
The FP load/store on arm64 have register indexed forms. And this
CL implements this optimization.

1. The total size of pkg/android_arm64 (excluding cmd/compile)
decreases about 400 bytes.

2. There is no regression in the go1 benchmark, the test case
GobEncode even gets slight improvement, excluding noise.

name                     old time/op    new time/op    delta
BinaryTree17-4              19.0s ± 0%     19.0s ± 1%    ~     (p=0.817 n=29+29)
Fannkuch11-4                9.94s ± 0%     9.95s ± 0%  +0.03%  (p=0.010 n=24+30)
FmtFprintfEmpty-4           233ns ± 0%     233ns ± 0%    ~     (all equal)
FmtFprintfString-4          427ns ± 0%     427ns ± 0%    ~     (p=0.649 n=30+30)
FmtFprintfInt-4             471ns ± 0%     471ns ± 0%    ~     (all equal)
FmtFprintfIntInt-4          730ns ± 0%     730ns ± 0%    ~     (all equal)
FmtFprintfPrefixedInt-4     889ns ± 0%     889ns ± 0%    ~     (all equal)
FmtFprintfFloat-4          1.21µs ± 0%    1.21µs ± 0%  +0.04%  (p=0.012 n=20+30)
FmtManyArgs-4              2.99µs ± 0%    2.99µs ± 0%    ~     (p=0.651 n=29+29)
GobDecode-4                42.4ms ± 1%    42.3ms ± 1%  -0.27%  (p=0.001 n=29+28)
GobEncode-4                37.8ms ±11%    36.0ms ± 0%  -4.67%  (p=0.000 n=30+26)
Gzip-4                      1.98s ± 1%     1.96s ± 1%  -1.26%  (p=0.000 n=30+30)
Gunzip-4                    175ms ± 0%     175ms ± 0%    ~     (p=0.988 n=29+29)
HTTPClientServer-4          854µs ± 5%     860µs ± 5%    ~     (p=0.236 n=28+29)
JSONEncode-4               88.8ms ± 0%    87.9ms ± 0%  -1.00%  (p=0.000 n=24+26)
JSONDecode-4                390ms ± 1%     392ms ± 2%  +0.48%  (p=0.025 n=30+30)
Mandelbrot200-4            19.5ms ± 0%    19.5ms ± 0%    ~     (p=0.894 n=24+29)
GoParse-4                  20.3ms ± 0%    20.1ms ± 1%  -0.94%  (p=0.000 n=27+26)
RegexpMatchEasy0_32-4       451ns ± 0%     451ns ± 0%    ~     (p=0.578 n=30+30)
RegexpMatchEasy0_1K-4      1.63µs ± 0%    1.63µs ± 0%    ~     (p=0.298 n=30+28)
RegexpMatchEasy1_32-4       431ns ± 0%     434ns ± 0%  +0.67%  (p=0.000 n=30+29)
RegexpMatchEasy1_1K-4      2.60µs ± 0%    2.64µs ± 0%  +1.36%  (p=0.000 n=28+26)
RegexpMatchMedium_32-4      744ns ± 0%     744ns ± 0%    ~     (p=0.474 n=29+29)
RegexpMatchMedium_1K-4      223µs ± 0%     223µs ± 0%  -0.08%  (p=0.038 n=26+30)
RegexpMatchHard_32-4       12.2µs ± 0%    12.3µs ± 0%  +0.27%  (p=0.000 n=29+30)
RegexpMatchHard_1K-4        373µs ± 0%     373µs ± 0%    ~     (p=0.219 n=29+28)
Revcomp-4                   2.84s ± 0%     2.84s ± 0%    ~     (p=0.130 n=28+28)
Template-4                  394ms ± 1%     392ms ± 1%  -0.52%  (p=0.001 n=30+30)
TimeParse-4                1.93µs ± 0%    1.93µs ± 0%    ~     (p=0.587 n=29+30)
TimeFormat-4               2.00µs ± 0%    2.00µs ± 0%  +0.07%  (p=0.001 n=28+27)
[Geo mean]                  306µs          305µs       -0.17%

name                     old speed      new speed      delta
GobDecode-4              18.1MB/s ± 1%  18.2MB/s ± 1%  +0.27%  (p=0.001 n=29+28)
GobEncode-4              20.3MB/s ±10%  21.3MB/s ± 0%  +4.64%  (p=0.000 n=30+26)
Gzip-4                   9.79MB/s ± 1%  9.91MB/s ± 1%  +1.28%  (p=0.000 n=30+30)
Gunzip-4                  111MB/s ± 0%   111MB/s ± 0%    ~     (p=0.988 n=29+29)
JSONEncode-4             21.8MB/s ± 0%  22.1MB/s ± 0%  +1.02%  (p=0.000 n=24+26)
JSONDecode-4             4.97MB/s ± 1%  4.95MB/s ± 2%  -0.45%  (p=0.031 n=30+30)
GoParse-4                2.85MB/s ± 1%  2.88MB/s ± 1%  +1.03%  (p=0.000 n=30+26)
RegexpMatchEasy0_32-4    70.9MB/s ± 0%  70.9MB/s ± 0%    ~     (p=0.904 n=29+28)
RegexpMatchEasy0_1K-4     627MB/s ± 0%   627MB/s ± 0%    ~     (p=0.156 n=30+30)
RegexpMatchEasy1_32-4    74.2MB/s ± 0%  73.7MB/s ± 0%  -0.67%  (p=0.000 n=30+29)
RegexpMatchEasy1_1K-4     393MB/s ± 0%   388MB/s ± 0%  -1.34%  (p=0.000 n=28+26)
RegexpMatchMedium_32-4   1.34MB/s ± 0%  1.34MB/s ± 0%    ~     (all equal)
RegexpMatchMedium_1K-4   4.59MB/s ± 0%  4.59MB/s ± 0%  +0.07%  (p=0.035 n=25+30)
RegexpMatchHard_32-4     2.61MB/s ± 0%  2.61MB/s ± 0%  -0.11%  (p=0.002 n=28+30)
RegexpMatchHard_1K-4     2.75MB/s ± 0%  2.75MB/s ± 0%  +0.15%  (p=0.001 n=30+24)
Revcomp-4                89.4MB/s ± 0%  89.4MB/s ± 0%    ~     (p=0.140 n=28+28)
Template-4               4.93MB/s ± 1%  4.95MB/s ± 1%  +0.51%  (p=0.001 n=30+30)
[Geo mean]               18.4MB/s       18.4MB/s       +0.37%

Change-Id: I9a6b521a971b21cfb51064e8e9b853cef8a1d071
Reviewed-on: https://go-review.googlesource.com/124636
Run-TryBot: Ben Shi <powerman1st@163.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
 2018-08-28 02:37:18 +00:00
Ben Shi
2b69ad0b3c cmd/compile: optimize arm's comparison 
The CMP/CMN/TST/TEQ perform similar to SUB/ADD/AND/XOR except
the result is abondoned, and only NZCV flags are affected.

This CL implements further optimization with them.

1. A micro benchmark test gets more than 9% improvment.
TSTTEQ-4                   6.99ms ± 0%    6.35ms ± 0%  -9.15%  (p=0.000 n=33+36)
(https://github.com/benshi001/ugo1/blob/master/tstteq2_test.go)

2. The go1 benckmark shows no regression, excluding noise.
name                     old time/op    new time/op    delta
BinaryTree17-4              25.7s ± 1%     25.7s ± 1%    ~     (p=0.830 n=40+40)
Fannkuch11-4                13.3s ± 0%     13.2s ± 0%  -0.65%  (p=0.000 n=40+34)
FmtFprintfEmpty-4           394ns ± 0%     394ns ± 0%    ~     (p=0.819 n=40+40)
FmtFprintfString-4          677ns ± 0%     677ns ± 0%  +0.06%  (p=0.039 n=39+40)
FmtFprintfInt-4             707ns ± 0%     706ns ± 0%  -0.14%  (p=0.000 n=40+39)
FmtFprintfIntInt-4         1.04µs ± 0%    1.04µs ± 0%  +0.10%  (p=0.000 n=29+31)
FmtFprintfPrefixedInt-4    1.10µs ± 0%    1.11µs ± 0%  +0.65%  (p=0.000 n=39+37)
FmtFprintfFloat-4          2.27µs ± 0%    2.26µs ± 0%  -0.53%  (p=0.000 n=39+40)
FmtManyArgs-4              3.96µs ± 0%    3.96µs ± 0%  +0.10%  (p=0.000 n=39+40)
GobDecode-4                53.4ms ± 1%    52.8ms ± 2%  -1.10%  (p=0.000 n=39+39)
GobEncode-4                50.3ms ± 3%    50.4ms ± 2%    ~     (p=0.089 n=40+39)
Gzip-4                      2.62s ± 0%     2.64s ± 0%  +0.60%  (p=0.000 n=40+39)
Gunzip-4                    312ms ± 0%     312ms ± 0%  +0.02%  (p=0.030 n=40+39)
HTTPClientServer-4         1.01ms ± 7%    0.98ms ± 7%  -2.37%  (p=0.000 n=40+39)
JSONEncode-4                126ms ± 1%     126ms ± 1%  -0.38%  (p=0.004 n=39+39)
JSONDecode-4                423ms ± 0%     426ms ± 2%  +0.72%  (p=0.001 n=39+40)
Mandelbrot200-4            18.4ms ± 0%    18.4ms ± 0%  +0.04%  (p=0.000 n=38+40)
GoParse-4                  22.8ms ± 0%    22.6ms ± 0%  -0.68%  (p=0.000 n=35+40)
RegexpMatchEasy0_32-4       699ns ± 0%     704ns ± 0%  +0.73%  (p=0.000 n=27+40)
RegexpMatchEasy0_1K-4      4.27µs ± 0%    4.26µs ± 0%  -0.09%  (p=0.000 n=35+38)
RegexpMatchEasy1_32-4       741ns ± 0%     735ns ± 0%  -0.85%  (p=0.000 n=40+35)
RegexpMatchEasy1_1K-4      5.53µs ± 0%    5.49µs ± 0%  -0.69%  (p=0.000 n=39+40)
RegexpMatchMedium_32-4     1.07µs ± 0%    1.04µs ± 2%  -2.34%  (p=0.000 n=40+40)
RegexpMatchMedium_1K-4      261µs ± 0%     261µs ± 0%  -0.16%  (p=0.000 n=40+39)
RegexpMatchHard_32-4       14.9µs ± 0%    14.9µs ± 0%  -0.18%  (p=0.000 n=39+40)
RegexpMatchHard_1K-4        445µs ± 0%     446µs ± 0%  +0.09%  (p=0.000 n=36+34)
Revcomp-4                  41.8ms ± 1%    41.8ms ± 1%    ~     (p=0.595 n=39+38)
Template-4                  530ms ± 1%     528ms ± 1%  -0.49%  (p=0.000 n=40+40)
TimeParse-4                3.39µs ± 0%    3.42µs ± 0%  +0.98%  (p=0.000 n=36+38)
TimeFormat-4               6.12µs ± 0%    6.07µs ± 0%  -0.81%  (p=0.000 n=34+38)
[Geo mean]                  384µs          383µs       -0.24%

name                     old speed      new speed      delta
GobDecode-4              14.4MB/s ± 1%  14.5MB/s ± 2%  +1.11%  (p=0.000 n=39+39)
GobEncode-4              15.3MB/s ± 3%  15.2MB/s ± 2%    ~     (p=0.104 n=40+39)
Gzip-4                   7.40MB/s ± 1%  7.36MB/s ± 0%  -0.60%  (p=0.000 n=40+39)
Gunzip-4                 62.2MB/s ± 0%  62.1MB/s ± 0%  -0.02%  (p=0.047 n=40+39)
JSONEncode-4             15.4MB/s ± 1%  15.4MB/s ± 2%  +0.39%  (p=0.002 n=39+39)
JSONDecode-4             4.59MB/s ± 0%  4.56MB/s ± 2%  -0.71%  (p=0.000 n=39+40)
GoParse-4                2.54MB/s ± 0%  2.56MB/s ± 0%  +0.72%  (p=0.000 n=26+40)
RegexpMatchEasy0_32-4    45.8MB/s ± 0%  45.4MB/s ± 0%  -0.75%  (p=0.000 n=38+40)
RegexpMatchEasy0_1K-4     240MB/s ± 0%   240MB/s ± 0%  +0.09%  (p=0.000 n=35+38)
RegexpMatchEasy1_32-4    43.1MB/s ± 0%  43.5MB/s ± 0%  +0.84%  (p=0.000 n=40+39)
RegexpMatchEasy1_1K-4     185MB/s ± 0%   186MB/s ± 0%  +0.69%  (p=0.000 n=39+40)
RegexpMatchMedium_32-4    936kB/s ± 1%   959kB/s ± 2%  +2.38%  (p=0.000 n=40+40)
RegexpMatchMedium_1K-4   3.92MB/s ± 0%  3.93MB/s ± 0%  +0.18%  (p=0.000 n=39+40)
RegexpMatchHard_32-4     2.15MB/s ± 0%  2.15MB/s ± 0%  +0.19%  (p=0.000 n=40+40)
RegexpMatchHard_1K-4     2.30MB/s ± 0%  2.30MB/s ± 0%    ~     (all equal)
Revcomp-4                60.8MB/s ± 1%  60.8MB/s ± 1%    ~     (p=0.600 n=39+38)
Template-4               3.66MB/s ± 1%  3.68MB/s ± 1%  +0.46%  (p=0.000 n=40+40)
[Geo mean]               12.8MB/s       12.8MB/s       +0.27%

Change-Id: I849161169ecf0876a04b7c1d3990fa8d1435215e
Reviewed-on: https://go-review.googlesource.com/122855
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
 2018-08-27 15:49:46 +00:00
Ben Shi
e03220a594 cmd/compile: optimize 386 code with FLDPI 
FLDPI pushes the constant pi to 387's register stack, which is
more efficient than MOVSSconst/MOVSDconst.

1. This optimization reduces 0.3KB of the total size of pkg/linux_386
(exlcuding cmd/compile).

2. There is little regression in the go1 benchmark.
name                     old time/op    new time/op    delta
BinaryTree17-4              3.30s ± 3%     3.30s ± 2%    ~     (p=0.759 n=40+39)
Fannkuch11-4                3.53s ± 1%     3.54s ± 1%    ~     (p=0.168 n=40+40)
FmtFprintfEmpty-4          45.5ns ± 3%    45.6ns ± 3%    ~     (p=0.553 n=40+40)
FmtFprintfString-4         78.4ns ± 3%    78.3ns ± 3%    ~     (p=0.593 n=40+40)
FmtFprintfInt-4            88.8ns ± 2%    89.9ns ± 2%    ~     (p=0.083 n=40+33)
FmtFprintfIntInt-4          140ns ± 4%     140ns ± 4%    ~     (p=0.656 n=40+40)
FmtFprintfPrefixedInt-4     180ns ± 2%     181ns ± 3%  +0.53%  (p=0.050 n=40+40)
FmtFprintfFloat-4           408ns ± 4%     411ns ± 3%    ~     (p=0.112 n=40+40)
FmtManyArgs-4               599ns ± 3%     602ns ± 3%    ~     (p=0.784 n=40+40)
GobDecode-4                7.24ms ± 6%    7.30ms ± 5%    ~     (p=0.171 n=40+40)
GobEncode-4                6.98ms ± 5%    6.89ms ± 8%    ~     (p=0.107 n=40+40)
Gzip-4                      396ms ± 4%     396ms ± 3%    ~     (p=0.852 n=40+40)
Gunzip-4                   41.3ms ± 3%    41.5ms ± 4%    ~     (p=0.221 n=40+40)
HTTPClientServer-4         63.4µs ± 3%    63.4µs ± 2%    ~     (p=0.895 n=39+40)
JSONEncode-4               17.5ms ± 2%    17.5ms ± 3%    ~     (p=0.090 n=40+40)
JSONDecode-4               60.6ms ± 3%    60.1ms ± 4%    ~     (p=0.184 n=40+40)
Mandelbrot200-4            7.80ms ± 3%    7.78ms ± 2%    ~     (p=0.512 n=40+40)
GoParse-4                  3.30ms ± 3%    3.28ms ± 2%  -0.61%  (p=0.034 n=40+40)
RegexpMatchEasy0_32-4       104ns ± 4%     103ns ± 4%    ~     (p=0.118 n=40+40)
RegexpMatchEasy0_1K-4       850ns ± 2%     848ns ± 2%    ~     (p=0.370 n=40+40)
RegexpMatchEasy1_32-4       112ns ± 4%     112ns ± 4%    ~     (p=0.848 n=40+40)
RegexpMatchEasy1_1K-4      1.04µs ± 4%    1.03µs ± 4%    ~     (p=0.333 n=40+40)
RegexpMatchMedium_32-4      132ns ± 4%     131ns ± 3%    ~     (p=0.527 n=40+40)
RegexpMatchMedium_1K-4     43.4µs ± 3%    43.5µs ± 3%    ~     (p=0.111 n=40+40)
RegexpMatchHard_32-4       2.24µs ± 4%    2.24µs ± 4%    ~     (p=0.441 n=40+40)
RegexpMatchHard_1K-4       67.9µs ± 3%    68.0µs ± 3%    ~     (p=0.095 n=40+40)
Revcomp-4                   1.84s ± 2%     1.84s ± 2%    ~     (p=0.677 n=40+40)
Template-4                 68.4ms ± 3%    68.6ms ± 3%    ~     (p=0.345 n=40+40)
TimeParse-4                 433ns ± 3%     433ns ± 3%    ~     (p=0.403 n=40+40)
TimeFormat-4                407ns ± 3%     406ns ± 3%    ~     (p=0.900 n=40+40)
[Geo mean]                 67.1µs         67.2µs       +0.04%

name                     old speed      new speed      delta
GobDecode-4               106MB/s ± 5%   105MB/s ± 5%    ~     (p=0.173 n=40+40)
GobEncode-4               110MB/s ± 5%   112MB/s ± 9%    ~     (p=0.104 n=40+40)
Gzip-4                   49.0MB/s ± 4%  49.1MB/s ± 4%    ~     (p=0.836 n=40+40)
Gunzip-4                  471MB/s ± 3%   468MB/s ± 4%    ~     (p=0.218 n=40+40)
JSONEncode-4              111MB/s ± 2%   111MB/s ± 3%    ~     (p=0.090 n=40+40)
JSONDecode-4             32.0MB/s ± 3%  32.3MB/s ± 4%    ~     (p=0.194 n=40+40)
GoParse-4                17.6MB/s ± 3%  17.7MB/s ± 2%  +0.62%  (p=0.035 n=40+40)
RegexpMatchEasy0_32-4     307MB/s ± 4%   309MB/s ± 4%  +0.70%  (p=0.041 n=40+40)
RegexpMatchEasy0_1K-4    1.20GB/s ± 3%  1.21GB/s ± 2%    ~     (p=0.353 n=40+40)
RegexpMatchEasy1_32-4     285MB/s ± 3%   284MB/s ± 4%    ~     (p=0.384 n=40+40)
RegexpMatchEasy1_1K-4     988MB/s ± 4%   992MB/s ± 3%    ~     (p=0.335 n=40+40)
RegexpMatchMedium_32-4   7.56MB/s ± 4%  7.57MB/s ± 4%    ~     (p=0.314 n=40+40)
RegexpMatchMedium_1K-4   23.6MB/s ± 3%  23.6MB/s ± 3%    ~     (p=0.107 n=40+40)
RegexpMatchHard_32-4     14.3MB/s ± 4%  14.3MB/s ± 4%    ~     (p=0.429 n=40+40)
RegexpMatchHard_1K-4     15.1MB/s ± 3%  15.1MB/s ± 3%    ~     (p=0.099 n=40+40)
Revcomp-4                 138MB/s ± 2%   138MB/s ± 2%    ~     (p=0.658 n=40+40)
Template-4               28.4MB/s ± 3%  28.3MB/s ± 3%    ~     (p=0.331 n=40+40)
[Geo mean]               80.8MB/s       80.8MB/s       +0.09%

Change-Id: I0cb715eead68ade097a302e7fb80ccbd1d1b511e
Reviewed-on: https://go-review.googlesource.com/130975
Run-TryBot: Ben Shi <powerman1st@163.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
 2018-08-25 02:39:49 +00:00
Ben Shi
3bc34385fa cmd/compile: introduce more read-modify-write operations for amd64 
Add suport of read-modify-write for AND/SUB/AND/OR/XOR on amd64.

1. The total size of pkg/linux_amd64 decreases about 4KB, excluding
cmd/compile.

2. The go1 benchmark shows a little improvement, excluding noise.

name                     old time/op    new time/op    delta
BinaryTree17-4              2.63s ± 3%     2.65s ± 4%   +1.01%  (p=0.037 n=35+35)
Fannkuch11-4                2.33s ± 2%     2.39s ± 2%   +2.49%  (p=0.000 n=35+35)
FmtFprintfEmpty-4          45.4ns ± 5%    40.8ns ± 6%  -10.09%  (p=0.000 n=35+35)
FmtFprintfString-4         73.3ns ± 4%    70.9ns ± 3%   -3.23%  (p=0.000 n=30+35)
FmtFprintfInt-4            79.9ns ± 4%    79.5ns ± 3%     ~     (p=0.736 n=34+35)
FmtFprintfIntInt-4          126ns ± 4%     125ns ± 4%     ~     (p=0.083 n=35+35)
FmtFprintfPrefixedInt-4     152ns ± 6%     152ns ± 3%     ~     (p=0.855 n=34+35)
FmtFprintfFloat-4           215ns ± 4%     213ns ± 4%     ~     (p=0.066 n=35+35)
FmtManyArgs-4               522ns ± 3%     506ns ± 3%   -3.15%  (p=0.000 n=35+35)
GobDecode-4                6.45ms ± 8%    6.51ms ± 7%   +0.96%  (p=0.026 n=35+35)
GobEncode-4                6.10ms ± 6%    6.02ms ± 8%     ~     (p=0.160 n=35+35)
Gzip-4                      228ms ± 3%     221ms ± 3%   -2.92%  (p=0.000 n=35+35)
Gunzip-4                   37.5ms ± 4%    37.2ms ± 3%   -0.78%  (p=0.036 n=35+35)
HTTPClientServer-4         58.7µs ± 2%    59.2µs ± 1%   +0.80%  (p=0.000 n=33+33)
JSONEncode-4               12.0ms ± 3%    12.2ms ± 3%   +1.84%  (p=0.008 n=35+35)
JSONDecode-4               57.0ms ± 4%    56.6ms ± 3%     ~     (p=0.320 n=35+35)
Mandelbrot200-4            3.82ms ± 3%    3.79ms ± 3%     ~     (p=0.074 n=35+35)
GoParse-4                  3.21ms ± 5%    3.24ms ± 4%     ~     (p=0.119 n=35+35)
RegexpMatchEasy0_32-4      76.3ns ± 4%    75.4ns ± 4%   -1.14%  (p=0.014 n=34+33)
RegexpMatchEasy0_1K-4       251ns ± 4%     254ns ± 3%   +1.28%  (p=0.016 n=35+35)
RegexpMatchEasy1_32-4      69.6ns ± 3%    70.1ns ± 3%   +0.82%  (p=0.005 n=35+35)
RegexpMatchEasy1_1K-4       367ns ± 4%     376ns ± 4%   +2.47%  (p=0.000 n=35+35)
RegexpMatchMedium_32-4      108ns ± 5%     104ns ± 4%   -3.18%  (p=0.000 n=35+35)
RegexpMatchMedium_1K-4     33.8µs ± 3%    32.7µs ± 3%   -3.27%  (p=0.000 n=35+35)
RegexpMatchHard_32-4       1.55µs ± 3%    1.52µs ± 3%   -1.64%  (p=0.000 n=35+35)
RegexpMatchHard_1K-4       46.6µs ± 3%    46.6µs ± 4%     ~     (p=0.149 n=35+35)
Revcomp-4                   416ms ± 7%     412ms ± 6%   -0.95%  (p=0.033 n=33+35)
Template-4                 64.3ms ± 3%    62.4ms ± 7%   -2.94%  (p=0.000 n=35+35)
TimeParse-4                 320ns ± 2%     322ns ± 3%     ~     (p=0.589 n=35+35)
TimeFormat-4                300ns ± 3%     300ns ± 3%     ~     (p=0.597 n=35+35)
[Geo mean]                 47.4µs         47.0µs        -0.86%

name                     old speed      new speed      delta
GobDecode-4               119MB/s ± 7%   118MB/s ± 7%   -0.96%  (p=0.027 n=35+35)
GobEncode-4               126MB/s ± 7%   127MB/s ± 6%     ~     (p=0.157 n=34+34)
Gzip-4                   85.3MB/s ± 3%  87.9MB/s ± 3%   +3.02%  (p=0.000 n=35+35)
Gunzip-4                  518MB/s ± 4%   522MB/s ± 3%   +0.79%  (p=0.037 n=35+35)
JSONEncode-4              162MB/s ± 3%   159MB/s ± 3%   -1.81%  (p=0.009 n=35+35)
JSONDecode-4             34.1MB/s ± 4%  34.3MB/s ± 3%     ~     (p=0.318 n=35+35)
GoParse-4                18.0MB/s ± 5%  17.9MB/s ± 4%     ~     (p=0.117 n=35+35)
RegexpMatchEasy0_32-4     419MB/s ± 3%   425MB/s ± 4%   +1.46%  (p=0.003 n=32+33)
RegexpMatchEasy0_1K-4    4.07GB/s ± 4%  4.02GB/s ± 3%   -1.28%  (p=0.014 n=35+35)
RegexpMatchEasy1_32-4     460MB/s ± 3%   456MB/s ± 4%   -0.82%  (p=0.004 n=35+35)
RegexpMatchEasy1_1K-4    2.79GB/s ± 4%  2.72GB/s ± 4%   -2.39%  (p=0.000 n=35+35)
RegexpMatchMedium_32-4   9.23MB/s ± 4%  9.53MB/s ± 4%   +3.16%  (p=0.000 n=35+35)
RegexpMatchMedium_1K-4   30.3MB/s ± 3%  31.3MB/s ± 3%   +3.38%  (p=0.000 n=35+35)
RegexpMatchHard_32-4     20.7MB/s ± 3%  21.0MB/s ± 3%   +1.67%  (p=0.000 n=35+35)
RegexpMatchHard_1K-4     22.0MB/s ± 3%  21.9MB/s ± 4%     ~     (p=0.277 n=35+33)
Revcomp-4                 612MB/s ± 7%   618MB/s ± 6%   +0.96%  (p=0.034 n=33+35)
Template-4               30.2MB/s ± 3%  31.1MB/s ± 6%   +3.05%  (p=0.000 n=35+35)
[Geo mean]                123MB/s        124MB/s        +0.64%

Change-Id: Ia025da272e07d0069413824bfff3471b106d6280
Reviewed-on: https://go-review.googlesource.com/121535
Run-TryBot: Ben Shi <powerman1st@163.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ilya Tocar <ilya.tocar@intel.com>
Reviewed-by: Keith Randall <khr@golang.org>
 2018-08-24 23:38:25 +00:00
Ben Shi
a0a7e9fc0c cmd/compile: implement "OPC $imm, (mem)" for 386 
New read-modify-write operations are introduced in this CL for 386.

1. The total size of pkg/linux_386 decreases about 10KB (excluding
cmd/compile).

2. The go1 benchmark shows little regression.
name                     old time/op    new time/op    delta
BinaryTree17-4              3.32s ± 4%     3.29s ± 2%    ~     (p=0.059 n=30+30)
Fannkuch11-4                3.49s ± 1%     3.46s ± 1%  -0.92%  (p=0.001 n=30+30)
FmtFprintfEmpty-4          47.7ns ± 2%    46.8ns ± 5%  -1.93%  (p=0.011 n=25+30)
FmtFprintfString-4         79.5ns ± 7%    80.2ns ± 3%  +0.89%  (p=0.001 n=28+29)
FmtFprintfInt-4            90.5ns ± 2%    92.1ns ± 2%  +1.82%  (p=0.014 n=22+30)
FmtFprintfIntInt-4          141ns ± 1%     144ns ± 3%  +2.23%  (p=0.013 n=22+30)
FmtFprintfPrefixedInt-4     183ns ± 2%     184ns ± 3%    ~     (p=0.080 n=21+30)
FmtFprintfFloat-4           409ns ± 3%     412ns ± 3%  +0.83%  (p=0.040 n=30+30)
FmtManyArgs-4               597ns ± 6%     607ns ± 4%  +1.71%  (p=0.006 n=30+30)
GobDecode-4                7.21ms ± 5%    7.18ms ± 6%    ~     (p=0.665 n=30+30)
GobEncode-4                7.17ms ± 6%    7.09ms ± 7%    ~     (p=0.117 n=29+30)
Gzip-4                      413ms ± 4%     399ms ± 4%  -3.48%  (p=0.000 n=30+30)
Gunzip-4                   41.3ms ± 4%    41.7ms ± 3%  +1.05%  (p=0.011 n=30+30)
HTTPClientServer-4         63.5µs ± 3%    62.9µs ± 2%  -0.97%  (p=0.017 n=30+27)
JSONEncode-4               20.3ms ± 5%    20.1ms ± 5%  -1.16%  (p=0.004 n=30+30)
JSONDecode-4               66.2ms ± 4%    67.7ms ± 4%  +2.21%  (p=0.000 n=30+30)
Mandelbrot200-4            5.16ms ± 3%    5.18ms ± 3%    ~     (p=0.123 n=30+30)
GoParse-4                  3.23ms ± 2%    3.27ms ± 2%  +1.08%  (p=0.006 n=30+30)
RegexpMatchEasy0_32-4      98.9ns ± 5%    97.1ns ± 4%  -1.83%  (p=0.006 n=30+30)
RegexpMatchEasy0_1K-4       842ns ± 3%     842ns ± 3%    ~     (p=0.550 n=30+30)
RegexpMatchEasy1_32-4       107ns ± 4%     105ns ± 4%  -1.93%  (p=0.012 n=30+30)
RegexpMatchEasy1_1K-4      1.03µs ± 4%    1.04µs ± 4%    ~     (p=0.304 n=30+30)
RegexpMatchMedium_32-4      132ns ± 2%     129ns ± 4%  -2.02%  (p=0.000 n=21+30)
RegexpMatchMedium_1K-4     44.1µs ± 4%    43.8µs ± 3%    ~     (p=0.641 n=30+30)
RegexpMatchHard_32-4       2.26µs ± 4%    2.23µs ± 4%  -1.28%  (p=0.023 n=30+30)
RegexpMatchHard_1K-4       68.1µs ± 3%    68.6µs ± 4%    ~     (p=0.089 n=30+30)
Revcomp-4                   1.85s ± 2%     1.84s ± 2%    ~     (p=0.072 n=30+30)
Template-4                 69.2ms ± 3%    68.5ms ± 3%  -1.04%  (p=0.012 n=30+30)
TimeParse-4                 441ns ± 3%     446ns ± 4%  +1.21%  (p=0.001 n=30+30)
TimeFormat-4                415ns ± 3%     415ns ± 3%    ~     (p=0.436 n=30+30)
[Geo mean]                 67.0µs         66.9µs       -0.17%

name                     old speed      new speed      delta
GobDecode-4               107MB/s ± 5%   107MB/s ± 6%    ~     (p=0.663 n=30+30)
GobEncode-4               107MB/s ± 6%   108MB/s ± 7%    ~     (p=0.117 n=29+30)
Gzip-4                   47.0MB/s ± 4%  48.7MB/s ± 4%  +3.61%  (p=0.000 n=30+30)
Gunzip-4                  470MB/s ± 4%   466MB/s ± 4%  -1.05%  (p=0.011 n=30+30)
JSONEncode-4             95.6MB/s ± 5%  96.7MB/s ± 5%  +1.16%  (p=0.005 n=30+30)
JSONDecode-4             29.3MB/s ± 4%  28.7MB/s ± 4%  -2.17%  (p=0.000 n=30+30)
GoParse-4                17.9MB/s ± 2%  17.7MB/s ± 2%  -1.06%  (p=0.007 n=30+30)
RegexpMatchEasy0_32-4     323MB/s ± 5%   329MB/s ± 4%  +1.93%  (p=0.006 n=30+30)
RegexpMatchEasy0_1K-4    1.22GB/s ± 3%  1.22GB/s ± 3%    ~     (p=0.496 n=30+30)
RegexpMatchEasy1_32-4     298MB/s ± 4%   303MB/s ± 4%  +1.84%  (p=0.017 n=30+30)
RegexpMatchEasy1_1K-4     995MB/s ± 4%   989MB/s ± 4%    ~     (p=0.307 n=30+30)
RegexpMatchMedium_32-4   7.56MB/s ± 4%  7.74MB/s ± 4%  +2.46%  (p=0.000 n=22+30)
RegexpMatchMedium_1K-4   23.2MB/s ± 4%  23.4MB/s ± 3%    ~     (p=0.651 n=30+30)
RegexpMatchHard_32-4     14.2MB/s ± 4%  14.3MB/s ± 4%  +1.29%  (p=0.021 n=30+30)
RegexpMatchHard_1K-4     15.0MB/s ± 3%  14.9MB/s ± 4%    ~     (p=0.069 n=30+29)
Revcomp-4                 138MB/s ± 2%   138MB/s ± 2%    ~     (p=0.072 n=30+30)
Template-4               28.1MB/s ± 3%  28.4MB/s ± 3%  +1.05%  (p=0.012 n=30+30)
[Geo mean]               79.7MB/s       80.2MB/s       +0.60%

Change-Id: I44a1dfc942c9a385904553c4fe1fa8e509c8aa31
Reviewed-on: https://go-review.googlesource.com/120916
Run-TryBot: Ben Shi <powerman1st@163.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
 2018-08-22 04:12:42 +00:00
Ben Shi
90f2fa0037 cmd/compile: optimize 386 code with MULLload/DIVSSload/DIVSDload 
IMULL/DIVSS/DIVSD all can take the source operand from memory
directly. And this CL implement that optimization.

1. The total size of pkg/linux_386 decreases about 84KB (excluding
cmd/compile).

2. The go1 benchmark shows little regression in total (excluding noise).
name                     old time/op    new time/op    delta
BinaryTree17-4              3.29s ± 2%     3.27s ± 4%    ~     (p=0.192 n=30+30)
Fannkuch11-4                3.49s ± 2%     3.54s ± 1%  +1.48%  (p=0.000 n=30+30)
FmtFprintfEmpty-4          45.9ns ± 3%    46.3ns ± 4%  +0.89%  (p=0.037 n=30+30)
FmtFprintfString-4         78.8ns ± 3%    78.7ns ± 4%    ~     (p=0.209 n=30+27)
FmtFprintfInt-4            91.0ns ± 2%    90.3ns ± 2%  -0.82%  (p=0.031 n=30+27)
FmtFprintfIntInt-4          142ns ± 4%     143ns ± 4%    ~     (p=0.136 n=30+30)
FmtFprintfPrefixedInt-4     181ns ± 3%     183ns ± 4%  +1.40%  (p=0.005 n=30+30)
FmtFprintfFloat-4           404ns ± 4%     408ns ± 3%    ~     (p=0.397 n=30+30)
FmtManyArgs-4               601ns ± 3%     609ns ± 5%    ~     (p=0.059 n=30+30)
GobDecode-4                7.21ms ± 5%    7.24ms ± 5%    ~     (p=0.612 n=30+30)
GobEncode-4                6.91ms ± 6%    6.91ms ± 6%    ~     (p=0.797 n=30+30)
Gzip-4                      398ms ± 6%     399ms ± 4%    ~     (p=0.173 n=30+30)
Gunzip-4                   41.7ms ± 3%    41.8ms ± 3%    ~     (p=0.423 n=30+30)
HTTPClientServer-4         62.3µs ± 2%    62.7µs ± 3%    ~     (p=0.085 n=29+30)
JSONEncode-4               21.0ms ± 4%    20.7ms ± 5%  -1.39%  (p=0.014 n=30+30)
JSONDecode-4               66.3ms ± 3%    67.4ms ± 1%  +1.71%  (p=0.003 n=30+24)
Mandelbrot200-4            5.15ms ± 3%    5.16ms ± 3%    ~     (p=0.697 n=30+30)
GoParse-4                  3.24ms ± 3%    3.27ms ± 4%  +0.91%  (p=0.032 n=30+30)
RegexpMatchEasy0_32-4       101ns ± 5%      99ns ± 4%  -1.82%  (p=0.008 n=29+30)
RegexpMatchEasy0_1K-4       848ns ± 4%     841ns ± 2%  -0.77%  (p=0.043 n=30+30)
RegexpMatchEasy1_32-4       106ns ± 6%     106ns ± 3%    ~     (p=0.939 n=29+30)
RegexpMatchEasy1_1K-4      1.02µs ± 3%    1.03µs ± 4%    ~     (p=0.297 n=28+30)
RegexpMatchMedium_32-4      129ns ± 4%     127ns ± 4%    ~     (p=0.073 n=30+30)
RegexpMatchMedium_1K-4     43.9µs ± 3%    43.8µs ± 3%    ~     (p=0.186 n=30+30)
RegexpMatchHard_32-4       2.24µs ± 4%    2.22µs ± 4%    ~     (p=0.332 n=30+29)
RegexpMatchHard_1K-4       68.0µs ± 4%    67.5µs ± 3%    ~     (p=0.290 n=30+30)
Revcomp-4                   1.85s ± 3%     1.85s ± 3%    ~     (p=0.358 n=30+30)
Template-4                 69.6ms ± 3%    70.0ms ± 4%    ~     (p=0.273 n=30+30)
TimeParse-4                 445ns ± 3%     441ns ± 3%    ~     (p=0.494 n=30+30)
TimeFormat-4                412ns ± 3%     412ns ± 6%    ~     (p=0.841 n=30+30)
[Geo mean]                 66.7µs         66.8µs       +0.13%

name                     old speed      new speed      delta
GobDecode-4               107MB/s ± 5%   106MB/s ± 5%    ~     (p=0.615 n=30+30)
GobEncode-4               111MB/s ± 6%   111MB/s ± 6%    ~     (p=0.790 n=30+30)
Gzip-4                   48.8MB/s ± 6%  48.7MB/s ± 4%    ~     (p=0.167 n=30+30)
Gunzip-4                  465MB/s ± 3%   465MB/s ± 3%    ~     (p=0.420 n=30+30)
JSONEncode-4             92.4MB/s ± 4%  93.7MB/s ± 5%  +1.42%  (p=0.015 n=30+30)
JSONDecode-4             29.3MB/s ± 3%  28.8MB/s ± 1%  -1.72%  (p=0.003 n=30+24)
GoParse-4                17.9MB/s ± 3%  17.7MB/s ± 4%  -0.89%  (p=0.037 n=30+30)
RegexpMatchEasy0_32-4     317MB/s ± 8%   324MB/s ± 4%  +2.14%  (p=0.006 n=30+30)
RegexpMatchEasy0_1K-4    1.21GB/s ± 4%  1.22GB/s ± 2%  +0.77%  (p=0.036 n=30+30)
RegexpMatchEasy1_32-4     298MB/s ± 7%   299MB/s ± 4%    ~     (p=0.511 n=30+30)
RegexpMatchEasy1_1K-4    1.00GB/s ± 3%  1.00GB/s ± 4%    ~     (p=0.304 n=28+30)
RegexpMatchMedium_32-4   7.75MB/s ± 4%  7.82MB/s ± 4%    ~     (p=0.089 n=30+30)
RegexpMatchMedium_1K-4   23.3MB/s ± 3%  23.4MB/s ± 3%    ~     (p=0.181 n=30+30)
RegexpMatchHard_32-4     14.3MB/s ± 4%  14.4MB/s ± 4%    ~     (p=0.320 n=30+29)
RegexpMatchHard_1K-4     15.1MB/s ± 4%  15.2MB/s ± 3%    ~     (p=0.273 n=30+30)
Revcomp-4                 137MB/s ± 3%   137MB/s ± 3%    ~     (p=0.352 n=30+30)
Template-4               27.9MB/s ± 3%  27.7MB/s ± 4%    ~     (p=0.277 n=30+30)
[Geo mean]               79.9MB/s       80.1MB/s       +0.15%

Change-Id: I97333cd8ddabb3c7c88ca5aa9e14a005b74d306d
Reviewed-on: https://go-review.googlesource.com/120695
Run-TryBot: Ben Shi <powerman1st@163.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
 2018-08-22 03:38:38 +00:00
Ben Shi
705f3c74e6 cmd/compile: optimize AMD64 with DIVSSload and DIVSDload 
DIVSSload & DIVSDload directly operate on a memory operand. And
binary size can be reduced by them, while the performance is
not affected.

The total size of pkg/linux_amd64 (excluding cmd/compile) decreases
about 6KB.

There is little regression in the go1 benchmark test (excluding noise).
name                     old time/op    new time/op    delta
BinaryTree17-4              2.63s ± 4%     2.62s ± 4%    ~     (p=0.809 n=30+30)
Fannkuch11-4                2.40s ± 2%     2.40s ± 2%    ~     (p=0.109 n=30+30)
FmtFprintfEmpty-4          43.1ns ± 4%    43.2ns ± 9%    ~     (p=0.168 n=30+30)
FmtFprintfString-4         73.6ns ± 4%    74.1ns ± 4%    ~     (p=0.069 n=30+30)
FmtFprintfInt-4            81.0ns ± 3%    81.4ns ± 5%    ~     (p=0.350 n=30+30)
FmtFprintfIntInt-4          127ns ± 4%     129ns ± 4%  +0.99%  (p=0.021 n=30+30)
FmtFprintfPrefixedInt-4     156ns ± 4%     155ns ± 4%    ~     (p=0.415 n=30+30)
FmtFprintfFloat-4           219ns ± 4%     218ns ± 4%    ~     (p=0.071 n=30+30)
FmtManyArgs-4               522ns ± 3%     518ns ± 3%  -0.68%  (p=0.034 n=30+30)
GobDecode-4                6.49ms ± 6%    6.52ms ± 6%    ~     (p=0.832 n=30+30)
GobEncode-4                6.10ms ± 9%    6.14ms ± 7%    ~     (p=0.485 n=30+30)
Gzip-4                      227ms ± 1%     224ms ± 4%    ~     (p=0.484 n=24+30)
Gunzip-4                   37.2ms ± 3%    36.8ms ± 4%    ~     (p=0.889 n=30+30)
HTTPClientServer-4         58.9µs ± 1%    58.7µs ± 2%  -0.42%  (p=0.003 n=28+28)
JSONEncode-4               12.0ms ± 3%    12.0ms ± 4%    ~     (p=0.523 n=30+30)
JSONDecode-4               54.6ms ± 4%    54.5ms ± 4%    ~     (p=0.708 n=30+30)
Mandelbrot200-4            3.78ms ± 4%    3.81ms ± 3%  +0.99%  (p=0.016 n=30+30)
GoParse-4                  3.20ms ± 4%    3.20ms ± 5%    ~     (p=0.994 n=30+30)
RegexpMatchEasy0_32-4      77.0ns ± 4%    75.9ns ± 3%  -1.39%  (p=0.006 n=29+30)
RegexpMatchEasy0_1K-4       255ns ± 4%     253ns ± 4%    ~     (p=0.091 n=30+30)
RegexpMatchEasy1_32-4      69.7ns ± 3%    70.3ns ± 4%    ~     (p=0.120 n=30+30)
RegexpMatchEasy1_1K-4       373ns ± 2%     378ns ± 3%  +1.43%  (p=0.000 n=21+26)
RegexpMatchMedium_32-4      107ns ± 2%     108ns ± 4%  +1.50%  (p=0.012 n=22+30)
RegexpMatchMedium_1K-4     34.0µs ± 1%    34.3µs ± 3%  +1.08%  (p=0.008 n=24+30)
RegexpMatchHard_32-4       1.53µs ± 3%    1.54µs ± 3%    ~     (p=0.234 n=30+30)
RegexpMatchHard_1K-4       46.7µs ± 4%    47.0µs ± 4%    ~     (p=0.420 n=30+30)
Revcomp-4                   411ms ± 7%     415ms ± 6%    ~     (p=0.059 n=30+30)
Template-4                 65.5ms ± 5%    66.9ms ± 4%  +2.21%  (p=0.001 n=30+30)
TimeParse-4                 317ns ± 3%     311ns ± 3%  -1.97%  (p=0.000 n=30+30)
TimeFormat-4                293ns ± 3%     294ns ± 3%    ~     (p=0.243 n=30+30)
[Geo mean]                 47.4µs         47.5µs       +0.17%

name                     old speed      new speed      delta
GobDecode-4               118MB/s ± 5%   118MB/s ± 6%    ~     (p=0.832 n=30+30)
GobEncode-4               125MB/s ± 7%   125MB/s ± 7%    ~     (p=0.625 n=29+30)
Gzip-4                   85.3MB/s ± 1%  86.6MB/s ± 4%    ~     (p=0.486 n=24+30)
Gunzip-4                  522MB/s ± 3%   527MB/s ± 4%    ~     (p=0.889 n=30+30)
JSONEncode-4              162MB/s ± 3%   162MB/s ± 4%    ~     (p=0.520 n=30+30)
JSONDecode-4             35.5MB/s ± 4%  35.6MB/s ± 4%    ~     (p=0.701 n=30+30)
GoParse-4                18.1MB/s ± 4%  18.1MB/s ± 4%    ~     (p=0.891 n=29+30)
RegexpMatchEasy0_32-4     416MB/s ± 4%   422MB/s ± 3%  +1.43%  (p=0.005 n=29+30)
RegexpMatchEasy0_1K-4    4.01GB/s ± 4%  4.04GB/s ± 4%    ~     (p=0.091 n=30+30)
RegexpMatchEasy1_32-4     460MB/s ± 3%   456MB/s ± 5%    ~     (p=0.123 n=30+30)
RegexpMatchEasy1_1K-4    2.74GB/s ± 2%  2.70GB/s ± 3%  -1.33%  (p=0.000 n=22+26)
RegexpMatchMedium_32-4   9.39MB/s ± 3%  9.19MB/s ± 4%  -2.06%  (p=0.001 n=28+30)
RegexpMatchMedium_1K-4   30.1MB/s ± 1%  29.8MB/s ± 3%  -1.04%  (p=0.008 n=24+30)
RegexpMatchHard_32-4     20.9MB/s ± 3%  20.8MB/s ± 3%    ~     (p=0.234 n=30+30)
RegexpMatchHard_1K-4     21.9MB/s ± 4%  21.8MB/s ± 4%    ~     (p=0.420 n=30+30)
Revcomp-4                 619MB/s ± 7%   612MB/s ± 7%    ~     (p=0.059 n=30+30)
Template-4               29.6MB/s ± 4%  29.0MB/s ± 4%  -2.16%  (p=0.002 n=30+30)
[Geo mean]                123MB/s        123MB/s       -0.33%

Change-Id: Ia59e077feae4f2824df79059daea4d0f678e3e4c
Reviewed-on: https://go-review.googlesource.com/120275
Run-TryBot: Ben Shi <powerman1st@163.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ilya Tocar <ilya.tocar@intel.com>
 2018-08-22 02:47:49 +00:00
Ilya Tocar
a3593685cf cmd/compile/internal/ssa: remove useless zero extension 
We generate MOVBLZX for byte-sized LoadReg, so
(MOVBQZX (LoadReg (Arg))) is the same as
(LoadReg (Arg)). Remove those zero extension where possible.
Triggers several times during all.bash.

Fixes #25378
Updates #15300

Change-Id: If50656e66f217832a13ee8f49c47997f4fcc093a
Reviewed-on: https://go-review.googlesource.com/115617
Run-TryBot: Ilya Tocar <ilya.tocar@intel.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
 2018-08-20 21:38:20 +00:00
Ilya Tocar
c292b32f33 cmd/compile: enable disjoint memmove inlining on amd64 
Memmove can use AVX/prefetches/other optional instructions, so
only do it for small sizes, when call overhead dominates.

Change-Id: Ice5e93deb11462217f7fb5fc350b703109bb4090
Reviewed-on: https://go-review.googlesource.com/112517
Run-TryBot: Ilya Tocar <ilya.tocar@intel.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Michael Munday <mike.munday@ibm.com>
 2018-08-20 21:10:12 +00:00
Ben Shi
0a382e0b7f cmd/compile: optimize ARMv7 code 
"AND $0xffff0000, Rx" will be encoded to 12 bytes.
1. MOVWload from the constant pool to Rtmp
2. AND Rtmp, Rx
3. a 4-byte item in the constant pool

It can be simplified to 8 bytes on ARMv7, since ARMv7 has
"MOVW $imm-16, Rx".
1. MOVW $0xffff, Rtmp
2. BIC Rtmp, Rx

The above optimization also applies to BICconst, ADDconst and
SUBconst.

1. The total size of pkg/android_arm (excluding cmd/compile)
   decreases about 2KB.

2. The go1 benchmark shows no regression, exlcuding noise.
name                     old time/op    new time/op    delta
BinaryTree17-4              25.5s ± 1%     25.2s ± 1%  -0.85%  (p=0.000 n=30+30)
Fannkuch11-4                13.3s ± 0%     13.3s ± 0%  +0.16%  (p=0.000 n=24+25)
FmtFprintfEmpty-4           397ns ± 0%     394ns ± 0%  -0.64%  (p=0.000 n=30+30)
FmtFprintfString-4          679ns ± 0%     678ns ± 0%    ~     (p=0.093 n=30+29)
FmtFprintfInt-4             708ns ± 0%     707ns ± 0%  -0.19%  (p=0.000 n=27+28)
FmtFprintfIntInt-4         1.05µs ± 0%    1.05µs ± 0%  -0.07%  (p=0.001 n=18+30)
FmtFprintfPrefixedInt-4    1.16µs ± 0%    1.15µs ± 0%  -0.41%  (p=0.000 n=29+30)
FmtFprintfFloat-4          2.26µs ± 0%    2.23µs ± 1%  -1.40%  (p=0.000 n=30+30)
FmtManyArgs-4              3.96µs ± 0%    3.95µs ± 0%  -0.29%  (p=0.000 n=29+30)
GobDecode-4                52.9ms ± 2%    53.4ms ± 2%  +0.92%  (p=0.004 n=28+30)
GobEncode-4                49.7ms ± 2%    49.8ms ± 2%    ~     (p=0.890 n=30+26)
Gzip-4                      2.61s ± 0%     2.60s ± 0%  -0.36%  (p=0.000 n=29+29)
Gunzip-4                    312ms ± 0%     311ms ± 0%  -0.13%  (p=0.000 n=30+28)
HTTPClientServer-4         1.02ms ± 8%    1.00ms ± 7%    ~     (p=0.224 n=29+26)
JSONEncode-4                125ms ± 1%     124ms ± 3%  -1.05%  (p=0.000 n=25+30)
JSONDecode-4                432ms ± 1%     436ms ± 2%    ~     (p=0.277 n=26+30)
Mandelbrot200-4            18.4ms ± 0%    18.4ms ± 0%  +0.02%  (p=0.001 n=28+25)
GoParse-4                  22.4ms ± 1%    22.3ms ± 1%  -0.41%  (p=0.000 n=28+28)
RegexpMatchEasy0_32-4       697ns ± 0%     706ns ± 0%  +1.23%  (p=0.000 n=19+30)
RegexpMatchEasy0_1K-4      4.27µs ± 0%    4.26µs ± 0%  -0.06%  (p=0.000 n=30+30)
RegexpMatchEasy1_32-4       741ns ± 0%     735ns ± 0%  -0.86%  (p=0.000 n=26+30)
RegexpMatchEasy1_1K-4      5.49µs ± 0%    5.49µs ± 0%  -0.03%  (p=0.023 n=25+30)
RegexpMatchMedium_32-4     1.05µs ± 2%    1.04µs ± 2%    ~     (p=0.893 n=30+30)
RegexpMatchMedium_1K-4      261µs ± 0%     261µs ± 0%  -0.11%  (p=0.000 n=29+30)
RegexpMatchHard_32-4       14.9µs ± 0%    14.9µs ± 0%  -0.36%  (p=0.000 n=23+29)
RegexpMatchHard_1K-4        446µs ± 0%     445µs ± 0%  -0.17%  (p=0.000 n=30+29)
Revcomp-4                  41.6ms ± 1%    41.7ms ± 1%  +0.27%  (p=0.040 n=28+30)
Template-4                  531ms ± 0%     532ms ± 1%    ~     (p=0.059 n=30+30)
TimeParse-4                3.40µs ± 0%    3.33µs ± 0%  -2.02%  (p=0.000 n=30+30)
TimeFormat-4               6.14µs ± 0%    6.11µs ± 0%  -0.45%  (p=0.000 n=27+29)
[Geo mean]                  384µs          383µs       -0.27%

name                     old speed      new speed      delta
GobDecode-4              14.5MB/s ± 2%  14.4MB/s ± 2%  -0.90%  (p=0.005 n=28+30)
GobEncode-4              15.4MB/s ± 2%  15.4MB/s ± 2%    ~     (p=0.741 n=30+25)
Gzip-4                   7.44MB/s ± 0%  7.47MB/s ± 1%  +0.37%  (p=0.000 n=25+30)
Gunzip-4                 62.3MB/s ± 0%  62.4MB/s ± 0%  +0.13%  (p=0.000 n=30+28)
JSONEncode-4             15.5MB/s ± 1%  15.6MB/s ± 3%  +1.07%  (p=0.000 n=25+30)
JSONDecode-4             4.48MB/s ± 0%  4.46MB/s ± 2%    ~     (p=0.655 n=23+30)
GoParse-4                2.58MB/s ± 1%  2.59MB/s ± 1%  +0.42%  (p=0.000 n=28+29)
RegexpMatchEasy0_32-4    45.9MB/s ± 0%  45.3MB/s ± 0%  -1.23%  (p=0.000 n=28+30)
RegexpMatchEasy0_1K-4     240MB/s ± 0%   240MB/s ± 0%  +0.07%  (p=0.000 n=30+30)
RegexpMatchEasy1_32-4    43.2MB/s ± 0%  43.5MB/s ± 0%  +0.85%  (p=0.000 n=30+28)
RegexpMatchEasy1_1K-4     186MB/s ± 0%   186MB/s ± 0%  +0.03%  (p=0.026 n=25+30)
RegexpMatchMedium_32-4    955kB/s ± 2%   960kB/s ± 2%    ~     (p=0.084 n=30+30)
RegexpMatchMedium_1K-4   3.92MB/s ± 0%  3.93MB/s ± 0%  +0.14%  (p=0.000 n=29+30)
RegexpMatchHard_32-4     2.14MB/s ± 0%  2.15MB/s ± 0%  +0.31%  (p=0.000 n=30+26)
RegexpMatchHard_1K-4     2.30MB/s ± 0%  2.30MB/s ± 0%    ~     (all equal)
Revcomp-4                61.1MB/s ± 1%  60.9MB/s ± 1%  -0.27%  (p=0.039 n=28+30)
Template-4               3.66MB/s ± 0%  3.65MB/s ± 1%  -0.14%  (p=0.045 n=30+30)
[Geo mean]               12.8MB/s       12.8MB/s       +0.04%

Change-Id: I02370e2584b4c041fddd324c97628fd6f0c12183
Reviewed-on: https://go-review.googlesource.com/123179
Run-TryBot: Ben Shi <powerman1st@163.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
 2018-08-20 15:13:23 +00:00
Ben Shi
556971316f cmd/compile: optimize 386's comparison 
CMPL/CMPW/CMPB can take a memory operand on 386, and this CL
implements that optimization.

1. The total size of pkg/linux_386 decreases about 45KB, excluding
cmd/compile.

2. The go1 benchmark shows a little improvement.
name                     old time/op    new time/op    delta
BinaryTree17-4              3.36s ± 2%     3.37s ± 3%    ~     (p=0.537 n=40+40)
Fannkuch11-4                3.59s ± 1%     3.53s ± 2%  -1.58%  (p=0.000 n=40+40)
FmtFprintfEmpty-4          46.0ns ± 3%    45.8ns ± 3%    ~     (p=0.249 n=40+40)
FmtFprintfString-4         80.0ns ± 4%    78.8ns ± 3%  -1.49%  (p=0.001 n=40+40)
FmtFprintfInt-4            89.7ns ± 2%    90.3ns ± 2%  +0.74%  (p=0.003 n=40+40)
FmtFprintfIntInt-4          144ns ± 3%     143ns ± 3%  -0.95%  (p=0.003 n=40+40)
FmtFprintfPrefixedInt-4     181ns ± 4%     180ns ± 2%    ~     (p=0.103 n=40+40)
FmtFprintfFloat-4           412ns ± 3%     408ns ± 4%  -0.97%  (p=0.018 n=40+40)
FmtManyArgs-4               607ns ± 4%     605ns ± 4%    ~     (p=0.148 n=40+40)
GobDecode-4                7.19ms ± 4%    7.24ms ± 5%    ~     (p=0.340 n=40+40)
GobEncode-4                7.04ms ± 9%    6.99ms ± 9%    ~     (p=0.289 n=40+40)
Gzip-4                      400ms ± 6%     398ms ± 5%    ~     (p=0.168 n=40+40)
Gunzip-4                   41.2ms ± 3%    41.7ms ± 3%  +1.40%  (p=0.001 n=40+40)
HTTPClientServer-4         62.5µs ± 1%    62.1µs ± 2%  -0.61%  (p=0.000 n=37+37)
JSONEncode-4               20.7ms ± 4%    20.4ms ± 3%  -1.60%  (p=0.000 n=40+40)
JSONDecode-4               69.4ms ± 4%    69.2ms ± 6%    ~     (p=0.177 n=40+40)
Mandelbrot200-4            5.22ms ± 6%    5.21ms ± 3%    ~     (p=0.531 n=40+40)
GoParse-4                  3.29ms ± 3%    3.28ms ± 3%    ~     (p=0.321 n=40+39)
RegexpMatchEasy0_32-4       104ns ± 4%     103ns ± 7%  -0.89%  (p=0.040 n=40+40)
RegexpMatchEasy0_1K-4       852ns ± 3%     853ns ± 2%    ~     (p=0.357 n=40+40)
RegexpMatchEasy1_32-4       113ns ± 8%     113ns ± 3%    ~     (p=0.906 n=40+40)
RegexpMatchEasy1_1K-4      1.03µs ± 4%    1.03µs ± 5%    ~     (p=0.326 n=40+40)
RegexpMatchMedium_32-4      136ns ± 3%     133ns ± 3%  -2.31%  (p=0.000 n=40+40)
RegexpMatchMedium_1K-4     44.0µs ± 3%    43.7µs ± 3%    ~     (p=0.053 n=40+40)
RegexpMatchHard_32-4       2.27µs ± 3%    2.26µs ± 4%    ~     (p=0.391 n=40+40)
RegexpMatchHard_1K-4       68.0µs ± 3%    68.9µs ± 3%  +1.28%  (p=0.000 n=40+40)
Revcomp-4                   1.86s ± 5%     1.86s ± 2%    ~     (p=0.950 n=40+40)
Template-4                 73.4ms ± 4%    69.9ms ± 7%  -4.78%  (p=0.000 n=40+40)
TimeParse-4                 449ns ± 4%     441ns ± 5%  -1.76%  (p=0.000 n=40+40)
TimeFormat-4                416ns ± 3%     417ns ± 4%    ~     (p=0.304 n=40+40)
[Geo mean]                 67.7µs         67.3µs       -0.55%

name                     old speed      new speed      delta
GobDecode-4               107MB/s ± 4%   106MB/s ± 5%    ~     (p=0.336 n=40+40)
GobEncode-4               109MB/s ± 5%   110MB/s ± 9%    ~     (p=0.142 n=38+40)
Gzip-4                   48.5MB/s ± 5%  48.8MB/s ± 5%    ~     (p=0.172 n=40+40)
Gunzip-4                  472MB/s ± 3%   465MB/s ± 3%  -1.39%  (p=0.001 n=40+40)
JSONEncode-4             93.6MB/s ± 4%  95.1MB/s ± 3%  +1.61%  (p=0.000 n=40+40)
JSONDecode-4             28.0MB/s ± 3%  28.1MB/s ± 6%    ~     (p=0.181 n=40+40)
GoParse-4                17.6MB/s ± 3%  17.7MB/s ± 3%    ~     (p=0.350 n=40+39)
RegexpMatchEasy0_32-4     308MB/s ± 4%   311MB/s ± 6%  +0.96%  (p=0.025 n=40+40)
RegexpMatchEasy0_1K-4    1.20GB/s ± 3%  1.20GB/s ± 2%    ~     (p=0.317 n=40+40)
RegexpMatchEasy1_32-4     282MB/s ± 7%   282MB/s ± 3%    ~     (p=0.516 n=40+40)
RegexpMatchEasy1_1K-4     994MB/s ± 4%   991MB/s ± 5%    ~     (p=0.319 n=40+40)
RegexpMatchMedium_32-4   7.31MB/s ± 3%  7.49MB/s ± 3%  +2.46%  (p=0.000 n=40+40)
RegexpMatchMedium_1K-4   23.3MB/s ± 3%  23.4MB/s ± 3%    ~     (p=0.052 n=40+40)
RegexpMatchHard_32-4     14.1MB/s ± 3%  14.1MB/s ± 4%    ~     (p=0.391 n=40+40)
RegexpMatchHard_1K-4     15.1MB/s ± 3%  14.9MB/s ± 3%  -1.27%  (p=0.000 n=40+40)
Revcomp-4                 137MB/s ± 5%   137MB/s ± 2%    ~     (p=0.942 n=40+40)
Template-4               26.5MB/s ± 4%  27.8MB/s ± 7%  +5.03%  (p=0.000 n=40+40)
[Geo mean]               78.6MB/s       79.0MB/s       +0.57%

Change-Id: Idcacc6881ef57cd7dc33aa87b711282842b72a53
Reviewed-on: https://go-review.googlesource.com/126618
Run-TryBot: Ben Shi <powerman1st@163.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
 2018-08-20 14:23:22 +00:00
Ben Shi
b75c5c5992 cmd/compile: optimize AMD64 with more read-modify-write operations 
6 more operations which do read-modify-write with a constant
source operand are added.

1. The total size of pkg/linux_amd64 decreases about 3KB, excluding
cmd/compile.

2. The go1 benckmark shows a slight improvement.
name                     old time/op    new time/op    delta
BinaryTree17-4              2.61s ± 4%     2.67s ± 2%  +2.26%  (p=0.000 n=30+29)
Fannkuch11-4                2.39s ± 2%     2.32s ± 2%  -2.67%  (p=0.000 n=30+30)
FmtFprintfEmpty-4          44.0ns ± 4%    41.7ns ± 4%  -5.15%  (p=0.000 n=30+30)
FmtFprintfString-4         74.2ns ± 4%    72.3ns ± 4%  -2.59%  (p=0.000 n=30+30)
FmtFprintfInt-4            81.7ns ± 3%    78.8ns ± 4%  -3.54%  (p=0.000 n=27+30)
FmtFprintfIntInt-4          130ns ± 4%     124ns ± 5%  -4.60%  (p=0.000 n=30+30)
FmtFprintfPrefixedInt-4     154ns ± 3%     152ns ± 3%  -1.13%  (p=0.012 n=30+30)
FmtFprintfFloat-4           215ns ± 4%     212ns ± 5%  -1.56%  (p=0.002 n=30+30)
FmtManyArgs-4               522ns ± 3%     512ns ± 3%  -1.84%  (p=0.001 n=30+30)
GobDecode-4                6.42ms ± 5%    6.49ms ± 7%    ~     (p=0.070 n=30+30)
GobEncode-4                6.07ms ± 8%    5.98ms ± 8%    ~     (p=0.150 n=30+30)
Gzip-4                      236ms ± 4%     223ms ± 4%  -5.57%  (p=0.000 n=30+30)
Gunzip-4                   37.4ms ± 3%    36.7ms ± 4%  -2.03%  (p=0.000 n=30+30)
HTTPClientServer-4         58.7µs ± 1%    58.5µs ± 2%  -0.37%  (p=0.018 n=30+29)
JSONEncode-4               12.0ms ± 4%    12.1ms ± 3%    ~     (p=0.112 n=30+30)
JSONDecode-4               54.5ms ± 3%    55.5ms ± 4%  +1.80%  (p=0.006 n=30+30)
Mandelbrot200-4            3.78ms ± 4%    3.78ms ± 4%    ~     (p=0.173 n=30+30)
GoParse-4                  3.16ms ± 5%    3.22ms ± 5%  +1.75%  (p=0.010 n=30+30)
RegexpMatchEasy0_32-4      76.6ns ± 1%    75.9ns ± 3%    ~     (p=0.672 n=25+30)
RegexpMatchEasy0_1K-4       252ns ± 3%     253ns ± 3%  +0.57%  (p=0.027 n=30+30)
RegexpMatchEasy1_32-4      69.8ns ± 4%    70.2ns ± 6%    ~     (p=0.539 n=30+30)
RegexpMatchEasy1_1K-4       374ns ± 3%     373ns ± 5%    ~     (p=0.263 n=30+30)
RegexpMatchMedium_32-4      107ns ± 4%     109ns ± 3%    ~     (p=0.067 n=30+30)
RegexpMatchMedium_1K-4     33.9µs ± 5%    34.1µs ± 4%    ~     (p=0.297 n=30+30)
RegexpMatchHard_32-4       1.54µs ± 3%    1.56µs ± 4%  +1.43%  (p=0.002 n=30+30)
RegexpMatchHard_1K-4       46.6µs ± 3%    47.0µs ± 3%    ~     (p=0.055 n=30+30)
Revcomp-4                   411ms ± 6%     407ms ± 6%    ~     (p=0.219 n=30+30)
Template-4                 66.8ms ± 3%    64.8ms ± 5%  -3.01%  (p=0.000 n=30+30)
TimeParse-4                 312ns ± 2%     319ns ± 3%  +2.50%  (p=0.000 n=30+30)
TimeFormat-4                296ns ± 5%     299ns ± 3%  +0.93%  (p=0.005 n=30+30)
[Geo mean]                 47.5µs         47.1µs       -0.75%

name                     old speed      new speed      delta
GobDecode-4               120MB/s ± 5%   118MB/s ± 6%    ~     (p=0.072 n=30+30)
GobEncode-4               127MB/s ± 8%   129MB/s ± 8%    ~     (p=0.150 n=30+30)
Gzip-4                   82.1MB/s ± 4%  87.0MB/s ± 4%  +5.90%  (p=0.000 n=30+30)
Gunzip-4                  519MB/s ± 4%   529MB/s ± 4%  +2.07%  (p=0.001 n=30+30)
JSONEncode-4              162MB/s ± 4%   161MB/s ± 3%    ~     (p=0.110 n=30+30)
JSONDecode-4             35.6MB/s ± 3%  35.0MB/s ± 4%  -1.77%  (p=0.007 n=30+30)
GoParse-4                18.3MB/s ± 4%  18.0MB/s ± 4%  -1.72%  (p=0.009 n=30+30)
RegexpMatchEasy0_32-4     418MB/s ± 1%   422MB/s ± 3%    ~     (p=0.645 n=25+30)
RegexpMatchEasy0_1K-4    4.06GB/s ± 3%  4.04GB/s ± 3%  -0.57%  (p=0.033 n=30+30)
RegexpMatchEasy1_32-4     459MB/s ± 4%   456MB/s ± 6%    ~     (p=0.530 n=30+30)
RegexpMatchEasy1_1K-4    2.73GB/s ± 3%  2.75GB/s ± 5%    ~     (p=0.279 n=30+30)
RegexpMatchMedium_32-4   9.28MB/s ± 5%  9.18MB/s ± 4%    ~     (p=0.086 n=30+30)
RegexpMatchMedium_1K-4   30.2MB/s ± 4%  30.0MB/s ± 4%    ~     (p=0.300 n=30+30)
RegexpMatchHard_32-4     20.8MB/s ± 3%  20.5MB/s ± 4%  -1.41%  (p=0.002 n=30+30)
RegexpMatchHard_1K-4     22.0MB/s ± 3%  21.8MB/s ± 3%    ~     (p=0.051 n=30+30)
Revcomp-4                 619MB/s ± 7%   625MB/s ± 7%    ~     (p=0.219 n=30+30)
Template-4               29.0MB/s ± 3%  29.9MB/s ± 4%  +3.11%  (p=0.000 n=30+30)
[Geo mean]                123MB/s        123MB/s       +0.28%

Change-Id: I850652cfd53329c1af804b7f57f4393d8097bb0d
Reviewed-on: https://go-review.googlesource.com/121135
Run-TryBot: Ben Shi <powerman1st@163.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ilya Tocar <ilya.tocar@intel.com>
 2018-08-20 14:18:39 +00:00
Ben Shi
de0e72610b test/codegen: add more combined store tests for arm64 
Some combined store optimization was already implemented
in go-1.11, but there is no corresponding test cases.

Change-Id: Iebdad186e92047942e53a74f2c20b390922e1e9c
Reviewed-on: https://go-review.googlesource.com/122915
Run-TryBot: Ben Shi <powerman1st@163.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
 2018-08-02 04:23:45 +00:00
Ben Shi
f9800a9473 test/codegen: add more test cases for arm64 
More test cases of combined load for arm64.

Change-Id: I7a9f4dcec6930f161cbded1f47dbf7fcef1db4f1
Reviewed-on: https://go-review.googlesource.com/122582
Run-TryBot: Ben Shi <powerman1st@163.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
 2018-07-10 15:41:15 +00:00
Ben Shi
8a85bce215 test/codegen: improve test cases for arm64 
1. Some incorrect test cases are disabled.
2. Some wrong test cases are corrected.
3. Some new test cases are added.

Change-Id: Ib5d0473d55159f233ddab79f96967eaec7b08597
Reviewed-on: https://go-review.googlesource.com/113736
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
 2018-05-22 14:50:41 +00:00
David Chase
c2c1822b12 cmd/compile: assign and preserve statement boundaries. 
A new pass run after ssa building (before any other
optimization) identifies the "first" ssa node for each
statement. Other "noise" nodes are tagged as being never
appropriate for a statement boundary (e.g., VarKill, VarDef,
Phi).

Rewrite, deadcode, cse, and nilcheck are modified to move
the statement boundaries forward whenever possible if a
boundary-tagged ssa value is removed; never-boundary nodes
are ignored in this search (some operations involving
constants are also tagged as never-boundary and also ignored
because they are likely to be moved or removed during
optimization).

Code generation treats all nodes except those explicitly
marked as statement boundaries as "not statement" nodes,
and floats statement boundaries to the beginning of each
same-line run of instructions found within a basic block.

Line number html conversion was modified to make statement
boundary nodes a bit more obvious by prepending a "+".

The code in fuse.go that glued together the value slices
of two blocks produced a result that depended on the
former capacities (not lengths) of the two slices.  This
causes differences in the 386 bootstrap, and also can
sometimes put values into an order that does a worse job
of preserving statement boundaries when values are removed.

Portions of two delve tests that had caught problems were
incorporated into ssa/debug_test.go.  There are some
opportunities to do better with optimized code, but the
next-ing is not lying or overly jumpy.

Over 4 CLs, compilebench geomean measured binary size
increase of 3.5% and compile user time increase of 3.8%
(this is after optimization to reuse a sparse map instead
of creating multiple maps.)

This CL worsens the optimized-debugging experience with
Delve; we need to work with the delve team so that
they can use the is_stmt marks that we're emitting now.

The reference output changes from time to time depending
on other changes in the compiler, sometimes better,
sometimes worse.

This CL now includes a test ensuring that 99+% of the lines
in the Go command itself (a handy optimized binary) include
is_stmt markers.

Change-Id: I359c94e06843f1eb41f9da437bd614885aa9644a
Reviewed-on: https://go-review.googlesource.com/102435
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
 2018-05-14 14:09:49 +00:00
Lynn Boger
e4172e5f5e cmd/compile/internal/ssa: initialize t.UInt in SetTypPtrs() 
Initialization of t.UInt is missing from SetTypPtrs in config.go,
preventing rules that use it from matching when they should.
This adds the initialization to allow those rules to work.

Updated test/codegen/rotate.go to test for this case, which
appears in math/bits RotateLeft32 and RotateLeft64. There had been
a testcase for this in go 1.10 but that went away when asm_test.go
was removed.

Change-Id: I82fc825ad8364df6fc36a69a1e448214d2e24ed5
Reviewed-on: https://go-review.googlesource.com/112518
Run-TryBot: Lynn Boger <laboger@linux.vnet.ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
 2018-05-10 14:50:30 +00:00
Michael Munday
6d00e8c478 cmd/compile: convert memmove call into Move when arguments are disjoint 
Move ops can be faster than memmove calls because the number of bytes
to be moved is fixed and they don't incur the overhead of a call.
This change allows memmove to be converted into a Move op when the
arguments are disjoint.

The optimization is only enabled on s390x at the moment, however
other architectures may also benefit from it in the future. The
memmove inlining rule triggers an extra 12 times when compiling the
standard library. It will most likely make more of a difference as the
disjoint function is improved over time (to recognize fresh heap
allocations for example).

Change-Id: I9af570dcfff28257b8e59e0ff584a46d8e248310
Reviewed-on: https://go-review.googlesource.com/110064
Run-TryBot: Michael Munday <mike.munday@ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ilya Tocar <ilya.tocar@intel.com>
 2018-05-09 11:20:40 +00:00
Martin Möhrmann
aee71dd70b cmd/compile: optimize map-clearing range idiom 
replace map clears of the form:

        for k := range m {
                delete(m, k)
        }

(where m is map with key type that is reflexive for ==)
with a new runtime function that clears the maps backing
array with a memclr and reinitializes the hmap struct.

Map key types that for example contain floats are not
replaced by this optimization since NaN keys cannot
be deleted from maps using delete.

name                           old time/op  new time/op  delta
GoMapClear/Reflexive/1         92.2ns ± 1%  47.1ns ± 2%  -48.89%  (p=0.000 n=9+9)
GoMapClear/Reflexive/10         108ns ± 1%    48ns ± 2%  -55.68%  (p=0.000 n=10+10)
GoMapClear/Reflexive/100        303ns ± 2%   110ns ± 3%  -63.56%  (p=0.000 n=10+10)
GoMapClear/Reflexive/1000      3.58µs ± 3%  1.23µs ± 2%  -65.49%  (p=0.000 n=9+10)
GoMapClear/Reflexive/10000     28.2µs ± 3%  10.3µs ± 2%  -63.55%  (p=0.000 n=9+10)
GoMapClear/NonReflexive/1       121ns ± 2%   124ns ± 7%     ~     (p=0.097 n=10+10)
GoMapClear/NonReflexive/10      137ns ± 2%   139ns ± 3%   +1.53%  (p=0.033 n=10+10)
GoMapClear/NonReflexive/100     331ns ± 3%   334ns ± 2%     ~     (p=0.342 n=10+10)
GoMapClear/NonReflexive/1000   3.64µs ± 3%  3.64µs ± 2%     ~     (p=0.887 n=9+10)
GoMapClear/NonReflexive/10000  28.1µs ± 2%  28.4µs ± 3%     ~     (p=0.247 n=10+10)

Fixes #20138

Change-Id: I181332a8ef434a4f0d89659f492d8711db3f3213
Reviewed-on: https://go-review.googlesource.com/110055
Reviewed-by: Keith Randall <khr@golang.org>
 2018-05-08 21:15:16 +00:00
Michael Munday
8af0c77df3 cmd/compile: simplify shift lowering on s390x 
Use conditional moves instead of subtractions with borrow to handle
saturation cases. This allows us to delete the SUBE/SUBEW ops and
associated rules from the SSA backend. Using conditional moves also
means we can detect when shift values are masked so I've added some
new rules to constant fold the relevant comparisons and masking ops.

Also use the new shiftIsBounded() function to avoid generating code
to handle saturation cases where possible.

Updates #25167 for s390x.

Change-Id: Ief9991c91267c9151ce4c5ec07642abb4dcc1c0d
Reviewed-on: https://go-review.googlesource.com/110070
Run-TryBot: Michael Munday <mike.munday@ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
 2018-05-08 16:19:56 +00:00
Lynn Boger
28edaf4584 cmd/compile,test: combine byte loads and stores on ppc64le 
CL 74410 added rules to combine consecutive byte loads and
stores when the byte order was little endian for ppc64le. This
is the corresponding change for bytes that are in big endian order.
These rules are all intended for a little endian target arch.

This adds new testcases in test/codegen/memcombine.go

Fixes #22496
Updates #24242

Benchmark improvement for encoding/binary:
name                      old time/op    new time/op    delta
ReadSlice1000Int32s-16      11.0µs ± 0%     9.0µs ± 0%  -17.47%  (p=0.029 n=4+4)
ReadStruct-16               2.47µs ± 1%    2.48µs ± 0%   +0.67%  (p=0.114 n=4+4)
ReadInts-16                  642ns ± 1%     630ns ± 1%   -2.02%  (p=0.029 n=4+4)
WriteInts-16                 654ns ± 0%     653ns ± 1%   -0.08%  (p=0.629 n=4+4)
WriteSlice1000Int32s-16     8.75µs ± 0%    8.20µs ± 0%   -6.19%  (p=0.029 n=4+4)
PutUint16-16                1.16ns ± 0%    0.93ns ± 0%  -19.83%  (p=0.029 n=4+4)
PutUint32-16                1.16ns ± 0%    0.93ns ± 0%  -19.83%  (p=0.029 n=4+4)
PutUint64-16                1.85ns ± 0%    0.93ns ± 0%  -49.73%  (p=0.029 n=4+4)
LittleEndianPutUint16-16    1.03ns ± 0%    0.93ns ± 0%   -9.71%  (p=0.029 n=4+4)
LittleEndianPutUint32-16    0.93ns ± 0%    0.93ns ± 0%     ~     (all equal)
LittleEndianPutUint64-16    0.93ns ± 0%    0.93ns ± 0%     ~     (all equal)
PutUvarint32-16             43.0ns ± 0%    43.1ns ± 0%   +0.12%  (p=0.429 n=4+4)
PutUvarint64-16              174ns ± 0%     175ns ± 0%   +0.29%  (p=0.429 n=4+4)

Updates made to functions in gcm.go to enable their matching. An existing
testcase prevents these functions from being replaced by those in encoding/binary
due to import dependencies.

Change-Id: Idb3bd1e6e7b12d86cd828fb29cb095848a3e485a
Reviewed-on: https://go-review.googlesource.com/98136
Run-TryBot: Lynn Boger <laboger@linux.vnet.ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
 2018-05-08 13:15:39 +00:00
Michael Munday
f31a18ded4 cmd/compile: add some generic composite type optimizations 
Propagate values through some wide Zero/Move operations. Among
other things this allows us to optimize some kinds of array
initialization. For example, the following code no longer
requires a temporary be allocated on the stack. Instead it
writes the values directly into the return value.

func f(i uint32) [4]uint32 {
    return [4]uint32{i, i+1, i+2, i+3}
}

The return value is unnecessarily cleared but removing that is
probably a task for dead store analysis (I think it needs to
be able to match multiple Store ops to wide Zero ops).

In order to reliably remove stack variables that are rendered
unnecessary by these new rules I've added a new generic version
of the unread autos elimination pass.

These rules are triggered more than 5000 times when building and
testing the standard library.

Updates #15925 (fixes for arrays of up to 4 elements).
Updates #24386 (fixes for up to 4 kept elements).
Updates #24416.

compilebench results:

name       old time/op       new time/op       delta
Template         353ms ± 5%        359ms ± 3%    ~     (p=0.143 n=10+10)
Unicode          219ms ± 1%        217ms ± 4%    ~     (p=0.740 n=7+10)
GoTypes          1.26s ± 1%        1.26s ± 2%    ~     (p=0.549 n=9+10)
Compiler         6.00s ± 1%        6.08s ± 1%  +1.42%  (p=0.000 n=9+8)
SSA              15.3s ± 2%        15.6s ± 1%  +2.43%  (p=0.000 n=10+10)
Flate            237ms ± 2%        240ms ± 2%  +1.31%  (p=0.015 n=10+10)
GoParser         285ms ± 1%        285ms ± 1%    ~     (p=0.878 n=8+8)
Reflect          797ms ± 3%        807ms ± 2%    ~     (p=0.065 n=9+10)
Tar              334ms ± 0%        335ms ± 4%    ~     (p=0.460 n=8+10)
XML              419ms ± 0%        423ms ± 1%  +0.91%  (p=0.001 n=7+9)
StdCmd           46.0s ± 0%        46.4s ± 0%  +0.85%  (p=0.000 n=9+9)

name       old user-time/op  new user-time/op  delta
Template         337ms ± 3%        346ms ± 5%    ~     (p=0.053 n=9+10)
Unicode          205ms ±10%        205ms ± 8%    ~     (p=1.000 n=10+10)
GoTypes          1.22s ± 2%        1.21s ± 3%    ~     (p=0.436 n=10+10)
Compiler         5.85s ± 1%        5.93s ± 0%  +1.46%  (p=0.000 n=10+8)
SSA              14.9s ± 1%        15.3s ± 1%  +2.62%  (p=0.000 n=10+10)
Flate            229ms ± 4%        228ms ± 6%    ~     (p=0.796 n=10+10)
GoParser         271ms ± 3%        275ms ± 4%    ~     (p=0.165 n=10+10)
Reflect          779ms ± 5%        775ms ± 2%    ~     (p=0.971 n=10+10)
Tar              317ms ± 4%        319ms ± 5%    ~     (p=0.853 n=10+10)
XML              404ms ± 4%        409ms ± 5%    ~     (p=0.436 n=10+10)

name       old alloc/op      new alloc/op      delta
Template        34.9MB ± 0%       35.0MB ± 0%  +0.26%  (p=0.000 n=10+10)
Unicode         29.3MB ± 0%       29.3MB ± 0%  +0.02%  (p=0.000 n=10+10)
GoTypes          115MB ± 0%        115MB ± 0%  +0.30%  (p=0.000 n=10+10)
Compiler         519MB ± 0%        521MB ± 0%  +0.30%  (p=0.000 n=10+10)
SSA             1.55GB ± 0%       1.57GB ± 0%  +1.34%  (p=0.000 n=10+9)
Flate           24.1MB ± 0%       24.2MB ± 0%  +0.10%  (p=0.000 n=10+10)
GoParser        28.1MB ± 0%       28.1MB ± 0%  +0.07%  (p=0.000 n=10+10)
Reflect         78.7MB ± 0%       78.7MB ± 0%  +0.03%  (p=0.000 n=8+10)
Tar             34.4MB ± 0%       34.5MB ± 0%  +0.12%  (p=0.000 n=10+10)
XML             43.2MB ± 0%       43.2MB ± 0%  +0.13%  (p=0.000 n=10+10)

name       old allocs/op     new allocs/op     delta
Template          330k ± 0%         330k ± 0%  -0.01%  (p=0.017 n=10+10)
Unicode           337k ± 0%         337k ± 0%  +0.01%  (p=0.000 n=9+10)
GoTypes          1.15M ± 0%        1.15M ± 0%  +0.03%  (p=0.000 n=10+10)
Compiler         4.77M ± 0%        4.77M ± 0%  +0.03%  (p=0.000 n=9+10)
SSA              12.5M ± 0%        12.6M ± 0%  +1.16%  (p=0.000 n=10+10)
Flate             221k ± 0%         221k ± 0%  +0.05%  (p=0.000 n=9+10)
GoParser          275k ± 0%         275k ± 0%  +0.01%  (p=0.014 n=10+9)
Reflect           944k ± 0%         944k ± 0%  -0.02%  (p=0.000 n=10+10)
Tar               324k ± 0%         323k ± 0%  -0.12%  (p=0.000 n=10+10)
XML               384k ± 0%         384k ± 0%  -0.01%  (p=0.001 n=10+10)

name       old object-bytes  new object-bytes  delta
Template         476kB ± 0%        476kB ± 0%  -0.04%  (p=0.000 n=10+10)
Unicode          218kB ± 0%        218kB ± 0%    ~     (all equal)
GoTypes         1.58MB ± 0%       1.58MB ± 0%  -0.04%  (p=0.000 n=10+10)
Compiler        6.25MB ± 0%       6.24MB ± 0%  -0.09%  (p=0.000 n=10+10)
SSA             15.9MB ± 0%       16.1MB ± 0%  +1.22%  (p=0.000 n=10+10)
Flate            304kB ± 0%        304kB ± 0%  -0.13%  (p=0.000 n=10+10)
GoParser         370kB ± 0%        370kB ± 0%  -0.00%  (p=0.000 n=10+10)
Reflect         1.27MB ± 0%       1.27MB ± 0%  -0.12%  (p=0.000 n=10+10)
Tar              421kB ± 0%        419kB ± 0%  -0.64%  (p=0.000 n=10+10)
XML              518kB ± 0%        517kB ± 0%  -0.12%  (p=0.000 n=10+10)

name       old export-bytes  new export-bytes  delta
Template        16.7kB ± 0%       16.7kB ± 0%    ~     (all equal)
Unicode         6.52kB ± 0%       6.52kB ± 0%    ~     (all equal)
GoTypes         29.2kB ± 0%       29.2kB ± 0%    ~     (all equal)
Compiler        88.0kB ± 0%       88.0kB ± 0%    ~     (all equal)
SSA              109kB ± 0%        109kB ± 0%    ~     (all equal)
Flate           4.49kB ± 0%       4.49kB ± 0%    ~     (all equal)
GoParser        8.10kB ± 0%       8.10kB ± 0%    ~     (all equal)
Reflect         7.71kB ± 0%       7.71kB ± 0%    ~     (all equal)
Tar             9.15kB ± 0%       9.15kB ± 0%    ~     (all equal)
XML             12.3kB ± 0%       12.3kB ± 0%    ~     (all equal)

name       old text-bytes    new text-bytes    delta
HelloSize        676kB ± 0%        672kB ± 0%  -0.59%  (p=0.000 n=10+10)
CmdGoSize       7.26MB ± 0%       7.24MB ± 0%  -0.18%  (p=0.000 n=10+10)

name       old data-bytes    new data-bytes    delta
HelloSize       10.2kB ± 0%       10.2kB ± 0%    ~     (all equal)
CmdGoSize        248kB ± 0%        248kB ± 0%    ~     (all equal)

name       old bss-bytes     new bss-bytes     delta
HelloSize        125kB ± 0%        125kB ± 0%    ~     (all equal)
CmdGoSize        145kB ± 0%        145kB ± 0%    ~     (all equal)

name       old exe-bytes     new exe-bytes     delta
HelloSize       1.46MB ± 0%       1.45MB ± 0%  -0.31%  (p=0.000 n=10+10)
CmdGoSize       14.7MB ± 0%       14.7MB ± 0%  -0.17%  (p=0.000 n=10+10)

Change-Id: Ic72b0c189dd542f391e1c9ab88a76e9148dc4285
Reviewed-on: https://go-review.googlesource.com/106495
Run-TryBot: Michael Munday <mike.munday@ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
 2018-05-08 10:31:21 +00:00
Ben Shi
098ca846c7 cmd/compile: emit more compact 386 instructions 
ADDL/SUBL/ANDL/ORL/XORL can have a memory operand as destination,
and this CL optimize the compiler to emit such instructions on
386 for more compact binary.

Here is test report:
1. The total size of pkg/linux_386/ and pkg/tool/linux_386/ decreases
about 14KB.
(pkg/linux_386/cmd/compile/ and pkg/tool/linux_386/compile are excluded)

2. The go1 benchmark shows little change, excluding ±2% noise.
name                     old time/op    new time/op    delta
BinaryTree17-4              3.34s ± 2%     3.38s ± 2%  +1.27%  (p=0.000 n=40+39)
Fannkuch11-4                3.55s ± 1%     3.51s ± 1%  -1.33%  (p=0.000 n=40+40)
FmtFprintfEmpty-4          46.3ns ± 3%    46.9ns ± 4%  +1.41%  (p=0.002 n=40+40)
FmtFprintfString-4         80.8ns ± 3%    80.4ns ± 6%  -0.54%  (p=0.044 n=40+40)
FmtFprintfInt-4            93.0ns ± 3%    92.2ns ± 4%  -0.88%  (p=0.007 n=39+40)
FmtFprintfIntInt-4          144ns ± 5%     145ns ± 2%  +0.78%  (p=0.015 n=40+40)
FmtFprintfPrefixedInt-4     184ns ± 2%     182ns ± 2%  -1.06%  (p=0.004 n=40+40)
FmtFprintfFloat-4           415ns ± 4%     419ns ± 4%    ~     (p=0.434 n=40+40)
FmtManyArgs-4               615ns ± 3%     619ns ± 3%    ~     (p=0.100 n=40+40)
GobDecode-4                7.30ms ± 6%    7.36ms ± 6%    ~     (p=0.074 n=40+40)
GobEncode-4                7.10ms ± 6%    7.21ms ± 5%    ~     (p=0.082 n=40+39)
Gzip-4                      364ms ± 3%     362ms ± 6%  -0.71%  (p=0.020 n=40+40)
Gunzip-4                   42.4ms ± 3%    42.2ms ± 3%    ~     (p=0.303 n=40+40)
HTTPClientServer-4         62.9µs ± 1%    62.9µs ± 1%    ~     (p=0.768 n=38+39)
JSONEncode-4               21.4ms ± 4%    21.5ms ± 5%    ~     (p=0.210 n=40+40)
JSONDecode-4               67.7ms ± 3%    67.9ms ± 4%    ~     (p=0.713 n=40+40)
Mandelbrot200-4            5.18ms ± 3%    5.21ms ± 3%  +0.59%  (p=0.021 n=40+40)
GoParse-4                  3.35ms ± 3%    3.34ms ± 2%    ~     (p=0.996 n=40+40)
RegexpMatchEasy0_32-4      98.5ns ± 5%    96.3ns ± 4%  -2.15%  (p=0.001 n=40+40)
RegexpMatchEasy0_1K-4       851ns ± 4%     850ns ± 5%    ~     (p=0.700 n=40+40)
RegexpMatchEasy1_32-4       105ns ± 7%     107ns ± 4%  +1.50%  (p=0.017 n=40+40)
RegexpMatchEasy1_1K-4      1.03µs ± 5%    1.03µs ± 4%    ~     (p=0.992 n=40+40)
RegexpMatchMedium_32-4      130ns ± 6%     128ns ± 4%  -1.66%  (p=0.012 n=40+40)
RegexpMatchMedium_1K-4     44.0µs ± 5%    43.6µs ± 3%    ~     (p=0.704 n=40+40)
RegexpMatchHard_32-4       2.29µs ± 3%    2.23µs ± 4%  -2.38%  (p=0.000 n=40+40)
RegexpMatchHard_1K-4       69.0µs ± 3%    68.1µs ± 3%  -1.28%  (p=0.003 n=40+40)
Revcomp-4                   1.85s ± 2%     1.87s ± 3%  +1.11%  (p=0.000 n=40+40)
Template-4                 69.8ms ± 3%    69.6ms ± 3%    ~     (p=0.125 n=40+40)
TimeParse-4                 442ns ± 5%     440ns ± 3%    ~     (p=0.585 n=40+40)
TimeFormat-4                419ns ± 3%     420ns ± 3%    ~     (p=0.824 n=40+40)
[Geo mean]                 67.3µs         67.2µs       -0.11%

name                     old speed      new speed      delta
GobDecode-4               105MB/s ± 6%   104MB/s ± 6%    ~     (p=0.074 n=40+40)
GobEncode-4               108MB/s ± 7%   107MB/s ± 5%    ~     (p=0.080 n=40+39)
Gzip-4                   53.3MB/s ± 3%  53.7MB/s ± 6%  +0.73%  (p=0.021 n=40+40)
Gunzip-4                  458MB/s ± 3%   460MB/s ± 3%    ~     (p=0.301 n=40+40)
JSONEncode-4             90.8MB/s ± 4%  90.3MB/s ± 4%    ~     (p=0.213 n=40+40)
JSONDecode-4             28.7MB/s ± 3%  28.6MB/s ± 4%    ~     (p=0.679 n=40+40)
GoParse-4                17.3MB/s ± 3%  17.3MB/s ± 2%    ~     (p=1.000 n=40+40)
RegexpMatchEasy0_32-4     325MB/s ± 5%   333MB/s ± 4%  +2.44%  (p=0.000 n=40+38)
RegexpMatchEasy0_1K-4    1.20GB/s ± 4%  1.21GB/s ± 5%    ~     (p=0.684 n=40+40)
RegexpMatchEasy1_32-4     303MB/s ± 7%   298MB/s ± 4%  -1.52%  (p=0.022 n=40+40)
RegexpMatchEasy1_1K-4     995MB/s ± 5%   996MB/s ± 4%    ~     (p=0.996 n=40+40)
RegexpMatchMedium_32-4   7.67MB/s ± 6%  7.80MB/s ± 4%  +1.68%  (p=0.011 n=40+40)
RegexpMatchMedium_1K-4   23.3MB/s ± 5%  23.5MB/s ± 3%    ~     (p=0.697 n=40+40)
RegexpMatchHard_32-4     14.0MB/s ± 3%  14.3MB/s ± 4%  +2.43%  (p=0.000 n=40+40)
RegexpMatchHard_1K-4     14.8MB/s ± 3%  15.0MB/s ± 3%  +1.30%  (p=0.003 n=40+40)
Revcomp-4                 137MB/s ± 2%   136MB/s ± 3%  -1.10%  (p=0.000 n=40+40)
Template-4               27.8MB/s ± 3%  27.9MB/s ± 3%    ~     (p=0.128 n=40+40)
[Geo mean]               79.6MB/s       79.9MB/s       +0.28%

Change-Id: I02a3efc125dc81e18fc8495eb2bf1bba59ab8733
Reviewed-on: https://go-review.googlesource.com/110157
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Ilya Tocar <ilya.tocar@intel.com>
 2018-05-08 06:44:54 +00:00
Martin Möhrmann
b9a59d9f2e cmd/compile: optimize len([]rune(string)) 
Adds a new runtime function to count runes in a string.
Modifies the compiler to detect the pattern len([]rune(string))
and replaces it with the new rune counting runtime function.

RuneCount/lenruneslice/ASCII                  27.8ns ± 2%  14.5ns ± 3%  -47.70%  (p=0.000 n=10+10)
RuneCount/lenruneslice/Japanese                126ns ± 2%    60ns ± 2%  -52.03%  (p=0.000 n=10+10)
RuneCount/lenruneslice/MixedLength             104ns ± 2%    50ns ± 1%  -51.71%  (p=0.000 n=10+9)

Fixes #24923

Change-Id: Ie9c7e7391a4e2cca675c5cdcc1e5ce7d523948b9
Reviewed-on: https://go-review.googlesource.com/108985
Run-TryBot: Martin Möhrmann <moehrmann@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
 2018-05-06 05:31:01 +00:00
Martin Möhrmann
a8a60ac2a7 cmd/compile: optimize append(x, make([]T, y)...) slice extension 
Changes the compiler to recognize the slice extension pattern

  append(x, make([]T, y)...)

and replace it with growslice and an optional memclr to avoid an allocation for make([]T, y).

Memclr is not called in case growslice already allocated a new cleared backing array
when T contains pointers.

amd64:
name                      old time/op    new time/op    delta
ExtendSlice/IntSlice         103ns ± 4%      57ns ± 4%   -44.55%  (p=0.000 n=18+18)
ExtendSlice/PointerSlice     155ns ± 3%      77ns ± 3%   -49.93%  (p=0.000 n=20+20)
ExtendSlice/NoGrow          50.2ns ± 3%     5.2ns ± 2%   -89.67%  (p=0.000 n=18+18)

name                      old alloc/op   new alloc/op   delta
ExtendSlice/IntSlice         64.0B ± 0%     32.0B ± 0%   -50.00%  (p=0.000 n=20+20)
ExtendSlice/PointerSlice     64.0B ± 0%     32.0B ± 0%   -50.00%  (p=0.000 n=20+20)
ExtendSlice/NoGrow           32.0B ± 0%      0.0B       -100.00%  (p=0.000 n=20+20)

name                      old allocs/op  new allocs/op  delta
ExtendSlice/IntSlice          2.00 ± 0%      1.00 ± 0%   -50.00%  (p=0.000 n=20+20)
ExtendSlice/PointerSlice      2.00 ± 0%      1.00 ± 0%   -50.00%  (p=0.000 n=20+20)
ExtendSlice/NoGrow            1.00 ± 0%      0.00       -100.00%  (p=0.000 n=20+20)

Fixes #21266

Change-Id: Idc3077665f63cbe89762b590c5967a864fd1c07f
Reviewed-on: https://go-review.googlesource.com/109517
Run-TryBot: Martin Möhrmann <moehrmann@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
 2018-05-06 04:28:23 +00:00
Martin Möhrmann
500d79c410 cmd/compile: refactor memclrrange for arrays and slices 
Rename memclrrange to signify that it does not handle
all types of range clears.

Simplify checks to detect the range clear idiom for
arrays and slices.

Add tests to verify the optimization for the slice
range clear idiom is being applied by the compiler.

Change-Id: I5c3b7c9a479699ebdb4c407fde692f30f377860c
Reviewed-on: https://go-review.googlesource.com/110477
Run-TryBot: Martin Möhrmann <moehrmann@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
 2018-05-02 04:20:25 +00:00
Ben Shi
aaf73c6d1e cmd/compile: optimize ARM64 with shifted register indexed load/store 
ARM64 supports efficient instructions which combine shift, addition, load/store
together. Such as "MOVD (R0)(R1<<3), R2" and "MOVWU R6, (R4)(R1<<2)".

This CL optimizes the compiler to emit such efficient instuctions. And below
is some test data.

1. binary size before/after
binary                 size change
pkg/linux_arm64        +80.1KB
pkg/tool/linux_arm64   +121.9KB
go                     -4.3KB
gofmt                  -64KB

2. go1 benchmark
There is big improvement for the test case Fannkuch11, and slight
improvement for sme others, excluding noise.

name                     old time/op    new time/op    delta
BinaryTree17-4              43.9s ± 2%     44.0s ± 2%     ~     (p=0.820 n=30+30)
Fannkuch11-4                30.6s ± 2%     24.5s ± 3%  -19.93%  (p=0.000 n=25+30)
FmtFprintfEmpty-4           500ns ± 0%     499ns ± 0%   -0.11%  (p=0.000 n=23+25)
FmtFprintfString-4         1.03µs ± 0%    1.04µs ± 3%     ~     (p=0.065 n=29+30)
FmtFprintfInt-4            1.15µs ± 3%    1.15µs ± 4%   -0.56%  (p=0.000 n=30+30)
FmtFprintfIntInt-4         1.80µs ± 5%    1.82µs ± 0%     ~     (p=0.094 n=30+24)
FmtFprintfPrefixedInt-4    2.17µs ± 5%    2.20µs ± 0%     ~     (p=0.100 n=30+23)
FmtFprintfFloat-4          3.08µs ± 3%    3.09µs ± 4%     ~     (p=0.123 n=30+30)
FmtManyArgs-4              7.41µs ± 4%    7.17µs ± 1%   -3.26%  (p=0.000 n=30+23)
GobDecode-4                93.7ms ± 0%    94.7ms ± 4%     ~     (p=0.685 n=24+30)
GobEncode-4                78.7ms ± 7%    77.1ms ± 0%     ~     (p=0.729 n=30+23)
Gzip-4                      4.01s ± 0%     3.97s ± 5%   -1.11%  (p=0.037 n=24+30)
Gunzip-4                    389ms ± 4%     384ms ± 0%     ~     (p=0.155 n=30+23)
HTTPClientServer-4          536µs ± 1%     537µs ± 1%     ~     (p=0.236 n=30+30)
JSONEncode-4                179ms ± 1%     182ms ± 6%     ~     (p=0.763 n=24+30)
JSONDecode-4                843ms ± 0%     839ms ± 6%   -0.42%  (p=0.003 n=25+30)
Mandelbrot200-4            46.5ms ± 0%    46.5ms ± 0%   +0.02%  (p=0.000 n=26+26)
GoParse-4                  44.3ms ± 6%    43.3ms ± 0%     ~     (p=0.067 n=30+27)
RegexpMatchEasy0_32-4      1.07µs ± 7%    1.07µs ± 4%     ~     (p=0.835 n=30+30)
RegexpMatchEasy0_1K-4      5.51µs ± 0%    5.49µs ± 0%   -0.35%  (p=0.000 n=23+26)
RegexpMatchEasy1_32-4      1.01µs ± 0%    1.02µs ± 4%   +0.96%  (p=0.014 n=24+30)
RegexpMatchEasy1_1K-4      7.43µs ± 0%    7.18µs ± 0%   -3.41%  (p=0.000 n=23+24)
RegexpMatchMedium_32-4     1.78µs ± 0%    1.81µs ± 4%   +1.47%  (p=0.012 n=23+30)
RegexpMatchMedium_1K-4      547µs ± 1%     542µs ± 3%   -0.90%  (p=0.003 n=24+30)
RegexpMatchHard_32-4       30.4µs ± 0%    29.7µs ± 0%   -2.15%  (p=0.000 n=19+23)
RegexpMatchHard_1K-4        913µs ± 0%     915µs ± 6%   +0.25%  (p=0.012 n=24+30)
Revcomp-4                   6.32s ± 1%     6.42s ± 4%     ~     (p=0.342 n=25+30)
Template-4                  868ms ± 6%     878ms ± 6%   +1.15%  (p=0.000 n=30+30)
TimeParse-4                4.57µs ± 4%    4.59µs ± 3%   +0.65%  (p=0.010 n=29+30)
TimeFormat-4               4.51µs ± 0%    4.50µs ± 0%   -0.27%  (p=0.000 n=27+24)
[Geo mean]                  695µs          689µs        -0.92%

name                     old speed      new speed      delta
GobDecode-4              8.19MB/s ± 0%  8.12MB/s ± 4%     ~     (p=0.680 n=24+30)
GobEncode-4              9.76MB/s ± 7%  9.96MB/s ± 0%     ~     (p=0.616 n=30+23)
Gzip-4                   4.84MB/s ± 0%  4.89MB/s ± 4%   +1.16%  (p=0.030 n=24+30)
Gunzip-4                 49.9MB/s ± 4%  50.6MB/s ± 0%     ~     (p=0.162 n=30+23)
JSONEncode-4             10.9MB/s ± 1%  10.7MB/s ± 6%     ~     (p=0.575 n=24+30)
JSONDecode-4             2.30MB/s ± 0%  2.32MB/s ± 5%   +0.72%  (p=0.003 n=22+30)
GoParse-4                1.31MB/s ± 6%  1.34MB/s ± 0%   +2.26%  (p=0.002 n=30+27)
RegexpMatchEasy0_32-4    30.0MB/s ± 6%  30.0MB/s ± 4%     ~     (p=1.000 n=30+30)
RegexpMatchEasy0_1K-4     186MB/s ± 0%   187MB/s ± 0%   +0.35%  (p=0.000 n=23+26)
RegexpMatchEasy1_32-4    31.8MB/s ± 0%  31.5MB/s ± 4%   -0.92%  (p=0.012 n=25+30)
RegexpMatchEasy1_1K-4     138MB/s ± 0%   143MB/s ± 0%   +3.53%  (p=0.000 n=23+24)
RegexpMatchMedium_32-4    560kB/s ± 0%   553kB/s ± 4%   -1.19%  (p=0.005 n=23+30)
RegexpMatchMedium_1K-4   1.87MB/s ± 0%  1.89MB/s ± 3%   +1.04%  (p=0.002 n=24+30)
RegexpMatchHard_32-4     1.05MB/s ± 0%  1.08MB/s ± 0%   +2.40%  (p=0.000 n=19+23)
RegexpMatchHard_1K-4     1.12MB/s ± 0%  1.12MB/s ± 5%   +0.12%  (p=0.006 n=25+30)
Revcomp-4                40.2MB/s ± 1%  39.6MB/s ± 4%     ~     (p=0.242 n=25+30)
Template-4               2.24MB/s ± 6%  2.21MB/s ± 6%   -1.15%  (p=0.000 n=30+30)
[Geo mean]               7.87MB/s       7.91MB/s        +0.44%

Change-Id: If374cb7abf83537aa0a176f73c0f736f7800db03
Reviewed-on: https://go-review.googlesource.com/108735
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
 2018-04-27 20:02:05 +00:00
Milan Knezevic
2959128dc5 cmd/compile: add softfloat support to mips64{,le} 
mips64 softfloat support is based on mips implementation and introduces
new enviroment variable GOMIPS64.

GOMIPS64 is a GOARCH=mips64{,le} specific option, for a choice between
hard-float and soft-float. Valid values are 'hardfloat' (default) and
'softfloat'. It is passed to the assembler as
'GOMIPS64_{hardfloat,softfloat}'.

Change-Id: I7f73078627f7cb37c588a38fb5c997fe09c56134
Reviewed-on: https://go-review.googlesource.com/108475
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
 2018-04-27 14:50:17 +00:00
Josh Bleecher Snyder
d9a50a6531 cmd/compile: use prove pass to detect Ctz of non-zero values 
On amd64, Ctz must include special handling of zeros.
But the prove pass has enough information to detect whether the input
is non-zero, allowing a more efficient lowering.

Introduce new CtzNonZero ops to capture and use this information.

Benchmark code:

func BenchmarkVisitBits(b *testing.B) {
	b.Run("8", func(b *testing.B) {
		for i := 0; i < b.N; i++ {
			x := uint8(0xff)
			for x != 0 {
				sink = bits.TrailingZeros8(x)
				x &= x - 1
			}
		}
	})

    // and similarly so for 16, 32, 64
}

name            old time/op  new time/op  delta
VisitBits/8-8   7.27ns ± 4%  5.58ns ± 4%  -23.35%  (p=0.000 n=28+26)
VisitBits/16-8  14.7ns ± 7%  10.5ns ± 4%  -28.43%  (p=0.000 n=30+28)
VisitBits/32-8  27.6ns ± 8%  19.3ns ± 3%  -30.14%  (p=0.000 n=30+26)
VisitBits/64-8  44.0ns ±11%  38.0ns ± 5%  -13.48%  (p=0.000 n=30+30)

Fixes #25077

Change-Id: Ie6e5bd86baf39ee8a4ca7cadcf56d934e047f957
Reviewed-on: https://go-review.googlesource.com/109358
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
 2018-04-26 18:22:28 +00:00
Carlos Eduardo Seo
ebb67d993a cmd/compile, cmd/internal/obj/ppc64: make math.Round an intrinsic on ppc64x 
This change implements math.Round as an intrinsic on ppc64x so it can be
done using a single instruction.

benchmark                   old ns/op     new ns/op     delta
BenchmarkRound-16           2.60          0.69          -73.46%

Change-Id: I9408363e96201abdfc73ced7bcd5f0c29db006a8
Reviewed-on: https://go-review.googlesource.com/109395
Run-TryBot: Lynn Boger <laboger@linux.vnet.ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Lynn Boger <laboger@linux.vnet.ibm.com>
 2018-04-26 14:12:09 +00:00