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Commit Graph

36335 Commits

Author SHA1 Message Date
Giovanni Bajo
5c40210987 cmd/compile: in prove, add transitive closure of relations
Implement it through a partial order datastructure, which
keeps the relations between SSA values in a forest of DAGs
and is able to discover contradictions.

In make.bash, this patch is able to prove hundreds of conditions
which were not proved before.

Compilebench:

name       old time/op       new time/op       delta
Template         371ms ± 2%        368ms ± 1%    ~     (p=0.222 n=5+5)
Unicode          203ms ± 6%        199ms ± 3%    ~     (p=0.421 n=5+5)
GoTypes          1.17s ± 4%        1.18s ± 1%    ~     (p=0.151 n=5+5)
Compiler         5.54s ± 2%        5.59s ± 1%    ~     (p=0.548 n=5+5)
SSA              12.9s ± 2%        13.2s ± 1%  +2.96%  (p=0.032 n=5+5)
Flate            245ms ± 2%        247ms ± 3%    ~     (p=0.690 n=5+5)
GoParser         302ms ± 6%        302ms ± 4%    ~     (p=0.548 n=5+5)
Reflect          764ms ± 4%        773ms ± 3%    ~     (p=0.095 n=5+5)
Tar              354ms ± 6%        361ms ± 3%    ~     (p=0.222 n=5+5)
XML              434ms ± 3%        429ms ± 1%    ~     (p=0.421 n=5+5)
StdCmd           22.6s ± 1%        22.9s ± 1%  +1.40%  (p=0.032 n=5+5)

name       old user-time/op  new user-time/op  delta
Template         436ms ± 8%        426ms ± 5%    ~     (p=0.579 n=5+5)
Unicode          219ms ±15%        219ms ±12%    ~     (p=1.000 n=5+5)
GoTypes          1.47s ± 6%        1.53s ± 6%    ~     (p=0.222 n=5+5)
Compiler         7.26s ± 4%        7.40s ± 2%    ~     (p=0.389 n=5+5)
SSA              17.7s ± 4%        18.5s ± 4%  +4.13%  (p=0.032 n=5+5)
Flate            257ms ± 5%        268ms ± 9%    ~     (p=0.333 n=5+5)
GoParser         354ms ± 6%        348ms ± 6%    ~     (p=0.913 n=5+5)
Reflect          904ms ± 2%        944ms ± 4%    ~     (p=0.056 n=5+5)
Tar              398ms ±11%        430ms ± 7%    ~     (p=0.079 n=5+5)
XML              501ms ± 7%        489ms ± 5%    ~     (p=0.444 n=5+5)

name       old text-bytes    new text-bytes    delta
HelloSize        670kB ± 0%        670kB ± 0%  +0.00%  (p=0.008 n=5+5)
CmdGoSize       7.22MB ± 0%       7.21MB ± 0%  -0.07%  (p=0.008 n=5+5)

name       old data-bytes    new data-bytes    delta
HelloSize       9.88kB ± 0%       9.88kB ± 0%    ~     (all equal)
CmdGoSize        248kB ± 0%        248kB ± 0%  -0.06%  (p=0.008 n=5+5)

name       old bss-bytes     new bss-bytes     delta
HelloSize        125kB ± 0%        125kB ± 0%    ~     (all equal)
CmdGoSize        145kB ± 0%        144kB ± 0%  -0.20%  (p=0.008 n=5+5)

name       old exe-bytes     new exe-bytes     delta
HelloSize       1.43MB ± 0%       1.43MB ± 0%    ~     (all equal)
CmdGoSize       14.5MB ± 0%       14.5MB ± 0%  -0.06%  (p=0.008 n=5+5)

Fixes #19714
Updates #20393

Change-Id: Ia090f5b5dc1bcd274ba8a39b233c1e1ace1b330e
Reviewed-on: https://go-review.googlesource.com/100277
Run-TryBot: Giovanni Bajo <rasky@develer.com>
Reviewed-by: David Chase <drchase@google.com>
2018-04-29 09:35:39 +00:00
Josh Bleecher Snyder
5af0b28a73 runtime: iterate over set bits in adjustpointers
There are several things combined in this change.

First, eliminate the gobitvector type in favor
of adding a ptrbit method to bitvector.
In non-performance-critical code, use that method.
In performance critical code, though, load the bitvector data
one byte at a time and iterate only over set bits.
To support that, add and use sys.Ctz8.

name                old time/op  new time/op  delta
StackCopyPtr-8      81.8ms ± 5%  78.9ms ± 3%   -3.58%  (p=0.000 n=97+96)
StackCopy-8         65.9ms ± 3%  62.8ms ± 3%   -4.67%  (p=0.000 n=96+92)
StackCopyNoCache-8   105ms ± 3%   102ms ± 3%   -3.38%  (p=0.000 n=96+95)

Change-Id: I00b80f45612708bd440b1a411a57fa6dfa24aa74
Reviewed-on: https://go-review.googlesource.com/109716
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
2018-04-29 05:24:44 +00:00
Josh Bleecher Snyder
13cd006139 runtime: add fast version of getArgInfo
getArgInfo is called a lot during stack copying.
In the common case it doesn't do much work,
but it cannot be inlined.

This change works around that.

name                old time/op  new time/op  delta
StackCopyPtr-8       108ms ± 5%    96ms ± 4%  -10.40%  (p=0.000 n=20+20)
StackCopy-8         82.6ms ± 3%  78.4ms ± 6%   -5.15%  (p=0.000 n=19+20)
StackCopyNoCache-8   130ms ± 3%   122ms ± 3%   -6.44%  (p=0.000 n=20+20)

Change-Id: If7d8a08c50a4e2e76e4331b399396c5dbe88c2ce
Reviewed-on: https://go-review.googlesource.com/108945
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
2018-04-29 03:33:09 +00:00
Austin Clements
0fd427fda7 runtime: use entry stack map at function entry
Currently, when the runtime looks up the stack map for a frame, it
uses frame.continpc - 1 unless continpc is the function entry PC, in
which case it uses frame.continpc. As a result, if continpc is the
function entry point (which happens for deferred frames), it will
actually look up the stack map *following* the first instruction.

I think, though I am not positive, that this is always okay today
because the first instruction of a function can never change the stack
map. It's usually not a CALL, so it doesn't have PCDATA. Or, if it is
a CALL, it has to have the entry stack map.

But we're about to start emitting stack maps at every instruction that
changes them, which means the first instruction can have PCDATA
(notably, in leaf functions that don't have a prologue).

To prepare for this, tweak how the runtime looks up stack map indexes
so that if continpc is the function entry point, it directly uses the
entry stack map.

For #24543.

Change-Id: I85aa818041cd26aff416f7b1fba186e9c8ca6568
Reviewed-on: https://go-review.googlesource.com/109349
Reviewed-by: Rick Hudson <rlh@golang.org>
2018-04-29 00:03:04 +00:00
bill_ofarrell
3c65bb5b90 cmd/asm: add s390x VMSLG instruction
This instruction was introduced on the z14 to accelerate "limbified"
multiplications for certain cryptographic algorithms. This change allows
it to be used in Go assembly.

Change-Id: Ic93dae7fec1756f662874c08a5abc435bce9dd9e
Reviewed-on: https://go-review.googlesource.com/109695
Run-TryBot: Michael Munday <mike.munday@ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-04-28 22:15:25 +00:00
fanzha02
d7f5c0360f cmd/internal/obj/arm64: reorder the assembler's optab entries
Current optab entries are unordered, because the new instructions
are added at the end of the optab. The patch reorders them by comments
in optab, such as arithmetic operations, logical operations and a
series of load/store etc.

The patch removes the VMOVS opcode because FMOVS already has the same
operation.

Change-Id: Iccdf89ecbb3875b9dfcb6e06be2cc19c7e5581a2
Reviewed-on: https://go-review.googlesource.com/109896
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2018-04-28 18:10:25 +00:00
Richard Musiol
adb52cff58 misc/wasm: wasm_exec: non-zero exit code on compile error
Return a non-zero exit code if the WebAssembly host fails to compile
the WebAssmbly bytecode to machine code.

Change-Id: I774309db2872b6a2de77a1b0392608058414160d
Reviewed-on: https://go-review.googlesource.com/110097
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-04-27 20:57:51 +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
Cherry Zhang
ceda47d08a cmd/link: fix plugin on linux/arm64
The init function and runtime.addmoduledata were not added when
building plugin, which caused the runtime could not find the
module.

Testplugin is still not enabled on linux/arm64
(https://go.googlesource.com/go/+/master/src/cmd/dist/test.go#948)
because the gold linker on the builder is too old, which fails
with an internal error (see issue #17138). I tested locally and
it passes.

Fixes #24940.
Updates #17138.

Change-Id: I26aebca6c38a3443af0949471fa12b6d550e8c6c
Reviewed-on: https://go-review.googlesource.com/109917
Run-TryBot: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2018-04-27 17:18:14 +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
62adf6fc2d cmd/internal/obj: convert unicode C to ASCII C
Hex before: d0 a1
Hex after: 43

Not sure where that came from.

Change-Id: I189e7e21f8faf480ba72846b956a149976f720f8
Reviewed-on: https://go-review.googlesource.com/109777
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-04-27 14:36:31 +00:00
Zhou Peng
1f56499d4d testing: fix typo mistake
Change-Id: I561640768c43491288e7f5bd1a34247787793dab
Reviewed-on: https://go-review.googlesource.com/109935
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-04-27 13:29:12 +00:00
Yasuhiro Matsumoto
e656aebb5b os: os: make Stat("*.txt") fail on windows
Fixes #24999

Change-Id: Ie0bb6a6e0fa3992cdd272d42347af65ae7c95463
Reviewed-on: https://go-review.googlesource.com/108755
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Alex Brainman <alex.brainman@gmail.com>
2018-04-27 10:04:48 +00:00
Daniel Martí
a835c7396d cmd/compile: add initial README
As a follow-up to the first README for cmd/compile/internal/ssa.

Since this is the parent package for all the compiler packages, this
README serves as an overview of the compiler and its packages. As more
READMEs are added for specific parts with more detail, such as ssa's,
they can be linked from this one.

Thanks to Iskander Sharipov, Josh Bleecher Snyder, Matthew Dempsky,
Alberto Donizetti, and Robert Griesemer for helping with all the details
in this document.

Change-Id: I820a535e25dce86ccc667ce1c6e92b75fc32f3af
Reviewed-on: https://go-review.googlesource.com/103935
Reviewed-by: Martin Möhrmann <moehrmann@google.com>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2018-04-27 07:51:59 +00:00
Josh Bleecher Snyder
a76249c38d cmd/compile: increase initial allocation of LSym.R
Not a big win, but cheap.

name        old alloc/op      new alloc/op      delta
Template         34.4MB ± 0%       34.4MB ± 0%  -0.20%  (p=0.000 n=15+15)
Unicode          29.2MB ± 0%       29.3MB ± 0%  +0.17%  (p=0.000 n=15+15)
GoTypes           113MB ± 0%        113MB ± 0%  -0.22%  (p=0.000 n=15+15)
Compiler          509MB ± 0%        508MB ± 0%  -0.11%  (p=0.000 n=15+14)
SSA              1.46GB ± 0%       1.46GB ± 0%  -0.08%  (p=0.000 n=14+15)
Flate            23.8MB ± 0%       23.7MB ± 0%  -0.22%  (p=0.000 n=15+15)
GoParser         27.9MB ± 0%       27.8MB ± 0%  -0.21%  (p=0.000 n=14+15)
Reflect          77.2MB ± 0%       77.0MB ± 0%  -0.27%  (p=0.000 n=14+15)
Tar              34.0MB ± 0%       33.9MB ± 0%  -0.21%  (p=0.000 n=13+15)
XML              42.6MB ± 0%       42.5MB ± 0%  -0.15%  (p=0.000 n=15+15)
[Geo mean]       75.8MB            75.7MB       -0.15%

name        old allocs/op     new allocs/op     delta
Template           322k ± 0%         320k ± 0%  -0.60%  (p=0.000 n=15+15)
Unicode            337k ± 0%         336k ± 0%  -0.23%  (p=0.000 n=12+15)
GoTypes           1.13M ± 0%        1.12M ± 0%  -0.58%  (p=0.000 n=15+14)
Compiler          4.67M ± 0%        4.65M ± 0%  -0.38%  (p=0.000 n=14+15)
SSA               11.7M ± 0%        11.6M ± 0%  -0.25%  (p=0.000 n=15+15)
Flate              216k ± 0%         214k ± 0%  -0.67%  (p=0.000 n=15+15)
GoParser           271k ± 0%         270k ± 0%  -0.57%  (p=0.000 n=15+15)
Reflect            927k ± 0%         920k ± 0%  -0.72%  (p=0.000 n=13+14)
Tar                318k ± 0%         316k ± 0%  -0.57%  (p=0.000 n=15+15)
XML                376k ± 0%         375k ± 0%  -0.46%  (p=0.000 n=14+14)
[Geo mean]         731k              727k       -0.50%

Change-Id: I1417c5881e866fb3efe62a3d0fbe1134275da31a
Reviewed-on: https://go-review.googlesource.com/109755
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-04-27 04:49:14 +00:00
Josh Bleecher Snyder
b9785fc844 cmd/compile: log Ctz non-zero proofs
I forgot this in CL 109358.

Change-Id: Ia5e8bd9cf43393f098b101a0d6a0c526e3e4f101
Reviewed-on: https://go-review.googlesource.com/109775
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-04-27 04:49:09 +00:00
Kevin Burke
6b55407d2f cmd/vet: remove "only" from error message
If the vetted function supplies zero arguments, previously you would
get an error message like this:

    Printf format %v reads arg #1, but call has only 0 args

"has only 0 args" is an odd construction, and "has 0 args" sounds
better. Getting rid of "only" in all cases simplifies the code and
reads just as well.

Change-Id: I4706dfe4a75f13bf4db9c0650e459ca676710752
Reviewed-on: https://go-review.googlesource.com/109457
Run-TryBot: Kevin Burke <kev@inburke.com>
Run-TryBot: David Symonds <dsymonds@golang.org>
Reviewed-by: David Symonds <dsymonds@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2018-04-27 03:07:26 +00:00
Daniel Martí
a6b183fabd cmd/link/internal/ld: simple cleanups
Simplify some C-style loops with range statements, and move some
declarations closer to their uses.

While at it, ensure that all the SymbolType consts are typed.

Change-Id: I04b06afb2c1fb249ef8093a0c5cca0a597d1e05c
Reviewed-on: https://go-review.googlesource.com/105217
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2018-04-27 01:45:19 +00:00
Matthew Dempsky
ae2a2d12f6 cmd/compile: cleaner solution for importing init functions
Using oldname+resolve is how typecheck handles this anyway.

Passes toolstash -cmp, with both -iexport enabled and disabled.

Change-Id: I12b0f0333d6b86ce6bfc4d416c461b5f15c1110d
Reviewed-on: https://go-review.googlesource.com/109715
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
2018-04-26 23:21:28 +00:00
Cherry Zhang
148a26539b runtime: remove stale comment about getcallerpc/sp
Getcallerpc/sp no longer takes argument.

Change-Id: I80b30020e798990c59c8ffd0a4e078af6a75aea0
Reviewed-on: https://go-review.googlesource.com/109696
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2018-04-26 22:06:33 +00:00
Hana Kim
e357ece0af cmd/trace: have tasks in a separate section (process group)
Also change tasks to be represented as "slices" instead of
asynchronous events which are more efficiently represented in trace
viewer data model. This change allows to utilize the flow events
(arrows) to represent task hierarchies.

Introduced RegionArgs and TaskArgs where the task id infomation and
goroutine id informations are stored for information-purpose.

Change-Id: I11bec7dd716fdfc5f94ea39661b2e51344367a6f
Reviewed-on: https://go-review.googlesource.com/109337
Reviewed-by: Heschi Kreinick <heschi@google.com>
2018-04-26 20:56:44 +00:00
Hana Kim
9eb64bdd71 misc/trace: update trace_viewer_full.html
Change-Id: I919444886a264bc11026faa8ccda193bf09a8d8d
Reviewed-on: https://go-review.googlesource.com/109675
Reviewed-by: Heschi Kreinick <heschi@google.com>
2018-04-26 20:26:23 +00:00
Josh Bleecher Snyder
8bf4b7e673 cmd/compile: convert amd64 BSFL and BSRL from tuple to result only
Change-Id: I220a459f67ecb310b6e9a526a1ff55527d421e70
Reviewed-on: https://go-review.googlesource.com/109416
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 19:29:17 +00:00
Cherry Zhang
5f5168e004 cmd/link, cmd/go: enable DWARF on darwin/arm and darwin/arm64
Fixes #24883.

Change-Id: Iff992ec3f2f31f4d82923d7cc806df4ee58e70b0
Reviewed-on: https://go-review.googlesource.com/108295
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Elias Naur <elias.naur@gmail.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2018-04-26 18:59:07 +00:00
Cherry Zhang
22f4280b9a runtime: remove the dummy arg of getcallersp
getcallersp is intrinsified, and so the dummy arg is no longer
needed. Remove it, as well as a few dummy args that are solely
to feed getcallersp.

Change-Id: Ibb6c948ff9c56537042b380ac3be3a91b247aaa6
Reviewed-on: https://go-review.googlesource.com/109596
Run-TryBot: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2018-04-26 18:57:20 +00:00
Alberto Donizetti
a3bafcf8cc doc: make chart.apis.google.com link not clickable
The example in the 'A web server' section of the effective Go document
uses Google's image charts API (at chart.apis.google.com).

The service is now deprecated (see developers.google.com/chart/image),
and visiting http://chart.apis.google.com gives a 404. The endpoint is
still active, so the Go code in the example still works, but there's
no point in making the link clickable by the user if the page returns
a 404.

Change the element to `<code>`.

Change-Id: Ie67f4723cfa636e3dc1460507055b6bbb2b0970c
Reviewed-on: https://go-review.googlesource.com/109576
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-04-26 18:26:06 +00:00
Lubomir I. Ivanov (VMware)
353bba37df os/exec: fix Win32 tests missing 'chcp'
'%SystemRoot%/System32/chcp.com' is a tool on Windows that
is used to change the active code page in the console.

'go test os/exec' can fail with:
"'chcp' is not recognized as an internal or external command"

The test uses a custom PATH variable but does not include
'%SystemRoot%/System32'. Always append that to PATH.

Updates #24709

Change-Id: I1ab83b326072e3f0086b391b836234bcfd8a1fb7
GitHub-Last-Rev: fb930529bb
GitHub-Pull-Request: golang/go#25088
Reviewed-on: https://go-review.googlesource.com/109361
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-04-26 18:25:25 +00:00
Lubomir I. Ivanov (VMware)
0d54fb5610 path/filepath: fix Win32 tests missing 'chcp'
'%SystemRoot%/System32/chcp.com' is a tool on Windows that
is used to change the active code page in the console.

'go test path/filepath' can fail with:
"'chcp' is not recognized as an internal or external command"

The test uses a custom PATH variable but does not include
'%SystemRoot%/System32'. Always append that to PATH.

Updates #24709

Change-Id: Ib4c83ffdcc5dd6eb7bb34c07386cf2ab61dcae57
GitHub-Last-Rev: fac92613cc
GitHub-Pull-Request: golang/go#25089
Reviewed-on: https://go-review.googlesource.com/109362
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-04-26 18:25:15 +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
Michael Munday
adbb6ec903 cmd/compile/internal/ssa: regenerate rewrite rules
Running 'go run *.go' in the gen directory resulted in this diff.

Change-Id: Iee398a720f54d3f2c3c122fc6fc45a708a39e45e
Reviewed-on: https://go-review.googlesource.com/109575
Run-TryBot: Michael Munday <mike.munday@ibm.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2018-04-26 18:06:33 +00:00
Ian Lance Taylor
d873a6d872 syscall: 32-bit MIPS splice system call returns int, not int64
Fixes #25106

Change-Id: I315817543b44aa581980828a32ecc224f8c0a44d
Reviewed-on: https://go-review.googlesource.com/109316
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-04-26 17:08:53 +00:00
Diogo Pinela
8cd00a5262 archive/zip: prevent writing data for a directory
When creating a directory, Writer.Create now returns a dummy
io.Writer that always returns an error on Write.

Fixes #24043

Change-Id: I7792f54440d45d22d0aa174cba5015ed5fab1c5c
Reviewed-on: https://go-review.googlesource.com/108615
Reviewed-by: Joe Tsai <thebrokentoaster@gmail.com>
Run-TryBot: Joe Tsai <thebrokentoaster@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2018-04-26 15:57:06 +00:00
Alberto Donizetti
2191c3a4b9 strings: clarify Replacer's replacement order
NewReplacer's documentation says that "replacements are performed in
order", meaning that substrings are replaced in the order they appear
in the target string, and not that the old->new replacements are
applied in the order they're passed to NewReplacer.

Rephrase the doc to make this clearer.

Fixes #25071

Change-Id: Icf3aa6a9d459b94764c9d577e4a76ad8c04d158d
Reviewed-on: https://go-review.googlesource.com/109375
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-04-26 15:11:58 +00:00
Balaram Makam
bf6530a25b cmd/asm: add VSRI instruction on ARM64
This change provides VSRI instruction for ChaCha20Poly1305 implementation.

Change-Id: Ifee727b6f3982b629b44a67cac5bbe87ca59027b
Reviewed-on: https://go-review.googlesource.com/109342
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2018-04-26 15:03:21 +00:00
Keith Randall
b4ac02972f cmd/link: fix test flag
Doesn't cause an error, see #25085.
But we should fix it nonetheless.

Change-Id: I7b6799e0a95475202cacefc3a7f02487e61bfd31
Reviewed-on: https://go-review.googlesource.com/109355
Reviewed-by: Heschi Kreinick <heschi@google.com>
2018-04-26 14:14:13 +00:00
Balaram Makam
f524268c40 cmd/compile: optimize ARM64 code with CMN/TST
Use CMN/TST to simplify comparisons. This can reduce the
register pressure by removing single def/use registers for example:
ADDW R0, R1, R8 -> CMNW R1, R0 ; CMN is an alias of ADDS.
CBZW R8, label  -> BEQ  label  ; single def/use of R8 removed.

Little change in performance of go1 benchmark on Amberwing:
name                   old time/op    new time/op    delta
RegexpMatchEasy0_32       247ns ± 0%     246ns ± 0%  -0.40%  (p=0.008 n=5+5)
RegexpMatchEasy0_1K       581ns ± 0%     580ns ± 0%    ~     (p=0.079 n=4+5)
RegexpMatchEasy1_32       244ns ± 0%     243ns ± 0%  -0.41%  (p=0.008 n=5+5)
RegexpMatchEasy1_1K       804ns ± 0%     806ns ± 0%  +0.25%  (p=0.016 n=5+4)
RegexpMatchMedium_32      313ns ± 0%     311ns ± 0%  -0.64%  (p=0.008 n=5+5)
RegexpMatchMedium_1K     52.2µs ± 0%    51.9µs ± 0%  -0.51%  (p=0.008 n=5+5)
RegexpMatchHard_32       2.76µs ± 3%    2.74µs ± 0%    ~     (p=0.683 n=5+5)
RegexpMatchHard_1K       78.8µs ± 0%    78.9µs ± 0%  +0.04%  (p=0.008 n=5+5)
FmtFprintfEmpty          58.6ns ± 0%    57.7ns ± 0%  -1.54%  (p=0.008 n=5+5)
FmtFprintfString          118ns ± 0%     115ns ± 0%  -2.54%  (p=0.008 n=5+5)
FmtFprintfInt             119ns ± 0%     119ns ± 0%    ~     (all equal)
FmtFprintfIntInt          192ns ± 0%     192ns ± 0%    ~     (all equal)
FmtFprintfPrefixedInt     224ns ± 0%     205ns ± 0%  -8.48%  (p=0.008 n=5+5)
FmtFprintfFloat           336ns ± 0%     333ns ± 1%    ~     (p=0.683 n=5+5)
FmtManyArgs               779ns ± 1%     760ns ± 1%  -2.41%  (p=0.008 n=5+5)
Gzip                      437ms ± 0%     436ms ± 0%  -0.27%  (p=0.008 n=5+5)
HTTPClientServer         90.1µs ± 1%    91.1µs ± 0%  +1.19%  (p=0.008 n=5+5)
JSONEncode               20.1ms ± 0%    20.2ms ± 1%    ~     (p=0.690 n=5+5)
JSONDecode               94.5ms ± 1%    94.1ms ± 1%    ~     (p=0.095 n=5+5)
Mandelbrot200            5.37ms ± 0%    5.37ms ± 0%    ~     (p=0.421 n=5+5)
TimeParse                 450ns ± 0%     446ns ± 0%  -0.89%  (p=0.000 n=5+4)
TimeFormat                483ns ± 1%     473ns ± 0%  -2.19%  (p=0.008 n=5+5)
Template                 90.6ms ± 0%    89.7ms ± 0%  -0.93%  (p=0.008 n=5+5)
GoParse                  5.97ms ± 0%    6.01ms ± 0%  +0.65%  (p=0.008 n=5+5)
BinaryTree17              11.8s ± 0%     11.7s ± 0%  -0.28%  (p=0.016 n=5+5)
Revcomp                   669ms ± 0%     669ms ± 0%    ~     (p=0.222 n=5+5)
Fannkuch11                3.28s ± 0%     3.34s ± 0%  +1.72%  (p=0.016 n=4+5)
[Geo mean]               46.6µs         46.3µs       -0.74%

name                   old speed      new speed      delta
RegexpMatchEasy0_32     129MB/s ± 0%   130MB/s ± 0%  +0.32%  (p=0.016 n=5+4)
RegexpMatchEasy0_1K    1.76GB/s ± 0%  1.76GB/s ± 0%  +0.13%  (p=0.016 n=4+5)
RegexpMatchEasy1_32     131MB/s ± 0%   132MB/s ± 0%  +0.32%  (p=0.008 n=5+5)
RegexpMatchEasy1_1K    1.27GB/s ± 0%  1.27GB/s ± 0%  -0.24%  (p=0.016 n=5+4)
RegexpMatchMedium_32   3.19MB/s ± 0%  3.21MB/s ± 0%  +0.63%  (p=0.008 n=5+5)
RegexpMatchMedium_1K   19.6MB/s ± 0%  19.7MB/s ± 0%  +0.51%  (p=0.029 n=4+4)
RegexpMatchHard_32     11.6MB/s ± 2%  11.7MB/s ± 0%    ~     (p=1.000 n=5+5)
RegexpMatchHard_1K     13.0MB/s ± 0%  13.0MB/s ± 0%    ~     (p=0.079 n=4+5)
Gzip                   44.4MB/s ± 0%  44.5MB/s ± 0%  +0.27%  (p=0.008 n=5+5)
JSONEncode             96.4MB/s ± 0%  96.2MB/s ± 1%    ~     (p=0.579 n=5+5)
JSONDecode             20.5MB/s ± 1%  20.6MB/s ± 1%    ~     (p=0.111 n=5+5)
Template               21.4MB/s ± 0%  21.6MB/s ± 0%  +0.94%  (p=0.008 n=5+5)
GoParse                9.70MB/s ± 0%  9.63MB/s ± 0%  -0.68%  (p=0.016 n=4+5)
Revcomp                 380MB/s ± 0%   380MB/s ± 0%    ~     (p=0.222 n=5+5)
[Geo mean]             55.3MB/s       55.4MB/s       +0.23%

Change-Id: I2e5338138991d9bc984e67b51212aa5d1b0f2a6b
Reviewed-on: https://go-review.googlesource.com/97335
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
2018-04-26 14:13:12 +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
Matthew Dempsky
736390c2bd cmd/compile: allow SSA of multi-field structs while instrumenting
When we moved racewalk to buildssa, we disabled SSA of structs with
2-4 fields while instrumenting because it caused false dependencies
because for "x.f" we would emit

    (StructSelect (Load (Addr x)) "f")

Even though we later simplify this to

    (Load (OffPtr (Addr x) "f"))

the instrumentation saw a load of x in its entirety and would issue
appropriate race/msan calls.

The fix taken here is to directly emit the OffPtr form when x.f is
addressable and can't be represented in SSA form.

Change-Id: I0caf37bced52e9c16937466b0ac8cab6d356e525
Reviewed-on: https://go-review.googlesource.com/109360
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2018-04-26 07:07:18 +00:00
Yuval Pavel Zholkover
58c231f244 runtime: FreeBSD fast clock_gettime HPET timecounter support
This is a followup for CL 93156.

Fixes #22942.

Change-Id: Ic6e2de44011d041b91454353a6f2e3b0cf590060
Reviewed-on: https://go-review.googlesource.com/108095
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2018-04-26 03:54:19 +00:00
Russ Cox
279b530d68 cmd/go: respect vet typecheck failures again
Now that #18395 is fixed, let's see if we can insist
on vet during go test being able to type-check
packages again.

Change-Id: Iaa55a4d9c582ba743df2347d28c24f130e16e406
Reviewed-on: https://go-review.googlesource.com/108555
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
2018-04-26 03:21:45 +00:00
Russ Cox
1a64025f2b cmd/go: disambiguate for-test packages in failure output
Now that we can tell when a package is a split-off copy
for testing, show that in the build failures.
For example, instead of:

	# regexp/syntax
	../../regexp/syntax/parse.go:9:2: can't find import: "strings"
	# path/filepath
	../../path/filepath/match.go:12:2: can't find import: "strings"
	# flag
	../../flag/flag.go:75:2: can't find import: "strings"

we now print

	# regexp/syntax [strings.test]
	../../regexp/syntax/parse.go:9:2: can't find import: "strings"
	# path/filepath [strings.test]
	../../path/filepath/match.go:12:2: can't find import: "strings"
	# flag [strings.test]
	../../flag/flag.go:75:2: can't find import: "strings"

which gives more of a hint about what is wrong.

This is especially helpful if a package is being built multiple times,
since it explains why an error might appear multiple times:

	$ go test regexp encoding/json
	# regexp
	../../regexp/exec.go:12:9: undefined: x
	# regexp [regexp.test]
	../../regexp/exec.go:12:9: undefined: x
	FAIL	regexp [build failed]
	FAIL	encoding/json [build failed]
	$

Change-Id: Ie325796f6c3cf0e23f306066be8e65a30cb6b939
Reviewed-on: https://go-review.googlesource.com/108155
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
2018-04-26 03:19:18 +00:00
Russ Cox
296e676575 cmd/go: add go list -test to describe test binaries
Tools should be able to ask cmd/go about the dependency
graph for test binaries instead of reinventing it themselves.
Allow them to do so, with the new list -test flag.

This also fixes and tests for a bug introduced in CL 104315
that was not properly splitting dependencies on the path
between package main and the package being tested.

Change-Id: I29eb454c82893f5ee70252aaaecd9fa376eaf3c8
Reviewed-on: https://go-review.googlesource.com/107916
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
2018-04-26 02:20:04 +00:00
Josh Bleecher Snyder
c5f0104daf cmd/compile: use intrinsic for LeadingZeros8 on amd64
The previous change sped up the pure computation form of LeadingZeros8.
This places it somewhat close to the table lookup form.
Depending on something that varies from toolchain to toolchain
(alignment, perhaps?), the slowdown from ditching the table lookup
is either 20% or 5%.

This benchmark is the best case scenario for the table lookup:
It is in the L1 cache already.

I think we're close enough that we can switch to the computational version,
and trust that the memory effects and binary size savings will be worth it.

Code:

func f8(x uint8)   { z = bits.LeadingZeros8(x) }

Before:

"".f8 STEXT nosplit size=34 args=0x8 locals=0x0
	0x0000 00000 (x.go:7)	TEXT	"".f8(SB), NOSPLIT, $0-8
	0x0000 00000 (x.go:7)	FUNCDATA	$0, gclocals·2a5305abe05176240e61b8620e19a815(SB)
	0x0000 00000 (x.go:7)	FUNCDATA	$1, gclocals·33cdeccccebe80329f1fdbee7f5874cb(SB)
	0x0000 00000 (x.go:7)	MOVBLZX	"".x+8(SP), AX
	0x0005 00005 (x.go:7)	MOVBLZX	AL, AX
	0x0008 00008 (x.go:7)	LEAQ	math/bits.len8tab(SB), CX
	0x000f 00015 (x.go:7)	MOVBLZX	(CX)(AX*1), AX
	0x0013 00019 (x.go:7)	ADDQ	$-8, AX
	0x0017 00023 (x.go:7)	NEGQ	AX
	0x001a 00026 (x.go:7)	MOVQ	AX, "".z(SB)
	0x0021 00033 (x.go:7)	RET

After:

"".f8 STEXT nosplit size=30 args=0x8 locals=0x0
	0x0000 00000 (x.go:7)	TEXT	"".f8(SB), NOSPLIT, $0-8
	0x0000 00000 (x.go:7)	FUNCDATA	$0, gclocals·2a5305abe05176240e61b8620e19a815(SB)
	0x0000 00000 (x.go:7)	FUNCDATA	$1, gclocals·33cdeccccebe80329f1fdbee7f5874cb(SB)
	0x0000 00000 (x.go:7)	MOVBLZX	"".x+8(SP), AX
	0x0005 00005 (x.go:7)	MOVBLZX	AL, AX
	0x0008 00008 (x.go:7)	LEAL	1(AX)(AX*1), AX
	0x000c 00012 (x.go:7)	BSRL	AX, AX
	0x000f 00015 (x.go:7)	ADDQ	$-8, AX
	0x0013 00019 (x.go:7)	NEGQ	AX
	0x0016 00022 (x.go:7)	MOVQ	AX, "".z(SB)
	0x001d 00029 (x.go:7)	RET

Change-Id: Icc7db50a7820fb9a3da8a816d6b6940d7f8e193e
Reviewed-on: https://go-review.googlesource.com/108942
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2018-04-25 21:34:15 +00:00
Josh Bleecher Snyder
1d321ada73 cmd/compile: optimize LeadingZeros(16|32) on amd64
Introduce Len8 and Len16 ops and provide optimized lowerings for them.
amd64 only for this CL, although it wouldn't surprise me
if other architectures also admit of optimized lowerings.

Also use and optimize the Len32 lowering, along the same lines.

Leave Len8 unused for the moment; a subsequent CL will enable it.

For 16 and 32 bits, this leads to a speed-up.

name              old time/op  new time/op  delta
LeadingZeros16-8  1.42ns ± 5%  1.23ns ± 5%  -13.42%  (p=0.000 n=20+20)
LeadingZeros32-8  1.25ns ± 5%  1.03ns ± 5%  -17.63%  (p=0.000 n=20+16)

Code:

func f16(x uint16) { z = bits.LeadingZeros16(x) }
func f32(x uint32) { z = bits.LeadingZeros32(x) }

Before:

"".f16 STEXT nosplit size=38 args=0x8 locals=0x0
	0x0000 00000 (x.go:8)	TEXT	"".f16(SB), NOSPLIT, $0-8
	0x0000 00000 (x.go:8)	FUNCDATA	$0, gclocals·2a5305abe05176240e61b8620e19a815(SB)
	0x0000 00000 (x.go:8)	FUNCDATA	$1, gclocals·33cdeccccebe80329f1fdbee7f5874cb(SB)
	0x0000 00000 (x.go:8)	MOVWLZX	"".x+8(SP), AX
	0x0005 00005 (x.go:8)	MOVWLZX	AX, AX
	0x0008 00008 (x.go:8)	BSRQ	AX, AX
	0x000c 00012 (x.go:8)	MOVQ	$-1, CX
	0x0013 00019 (x.go:8)	CMOVQEQ	CX, AX
	0x0017 00023 (x.go:8)	ADDQ	$-15, AX
	0x001b 00027 (x.go:8)	NEGQ	AX
	0x001e 00030 (x.go:8)	MOVQ	AX, "".z(SB)
	0x0025 00037 (x.go:8)	RET

"".f32 STEXT nosplit size=34 args=0x8 locals=0x0
	0x0000 00000 (x.go:9)	TEXT	"".f32(SB), NOSPLIT, $0-8
	0x0000 00000 (x.go:9)	FUNCDATA	$0, gclocals·2a5305abe05176240e61b8620e19a815(SB)
	0x0000 00000 (x.go:9)	FUNCDATA	$1, gclocals·33cdeccccebe80329f1fdbee7f5874cb(SB)
	0x0000 00000 (x.go:9)	MOVL	"".x+8(SP), AX
	0x0004 00004 (x.go:9)	BSRQ	AX, AX
	0x0008 00008 (x.go:9)	MOVQ	$-1, CX
	0x000f 00015 (x.go:9)	CMOVQEQ	CX, AX
	0x0013 00019 (x.go:9)	ADDQ	$-31, AX
	0x0017 00023 (x.go:9)	NEGQ	AX
	0x001a 00026 (x.go:9)	MOVQ	AX, "".z(SB)
	0x0021 00033 (x.go:9)	RET

After:

"".f16 STEXT nosplit size=30 args=0x8 locals=0x0
	0x0000 00000 (x.go:8)	TEXT	"".f16(SB), NOSPLIT, $0-8
	0x0000 00000 (x.go:8)	FUNCDATA	$0, gclocals·2a5305abe05176240e61b8620e19a815(SB)
	0x0000 00000 (x.go:8)	FUNCDATA	$1, gclocals·33cdeccccebe80329f1fdbee7f5874cb(SB)
	0x0000 00000 (x.go:8)	MOVWLZX	"".x+8(SP), AX
	0x0005 00005 (x.go:8)	MOVWLZX	AX, AX
	0x0008 00008 (x.go:8)	LEAL	1(AX)(AX*1), AX
	0x000c 00012 (x.go:8)	BSRL	AX, AX
	0x000f 00015 (x.go:8)	ADDQ	$-16, AX
	0x0013 00019 (x.go:8)	NEGQ	AX
	0x0016 00022 (x.go:8)	MOVQ	AX, "".z(SB)
	0x001d 00029 (x.go:8)	RET

"".f32 STEXT nosplit size=28 args=0x8 locals=0x0
	0x0000 00000 (x.go:9)	TEXT	"".f32(SB), NOSPLIT, $0-8
	0x0000 00000 (x.go:9)	FUNCDATA	$0, gclocals·2a5305abe05176240e61b8620e19a815(SB)
	0x0000 00000 (x.go:9)	FUNCDATA	$1, gclocals·33cdeccccebe80329f1fdbee7f5874cb(SB)
	0x0000 00000 (x.go:9)	MOVL	"".x+8(SP), AX
	0x0004 00004 (x.go:9)	LEAQ	1(AX)(AX*1), AX
	0x0009 00009 (x.go:9)	BSRQ	AX, AX
	0x000d 00013 (x.go:9)	ADDQ	$-32, AX
	0x0011 00017 (x.go:9)	NEGQ	AX
	0x0014 00020 (x.go:9)	MOVQ	AX, "".z(SB)
	0x001b 00027 (x.go:9)	RET

Change-Id: I6c93c173752a7bfdeab8be30777ae05a736e1f4b
Reviewed-on: https://go-review.googlesource.com/108941
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Giovanni Bajo <rasky@develer.com>
Reviewed-by: Keith Randall <khr@golang.org>
2018-04-25 21:34:04 +00:00
Josh Bleecher Snyder
54dbab5221 cmd/compile: optimize TrailingZeros(8|16) on amd64
Introduce Ctz8 and Ctz16 ops and provide optimized lowerings for them.
amd64 only for this CL, although it wouldn't surprise me
if other architectures also admit of optimized lowerings.

name               old time/op  new time/op  delta
TrailingZeros8-8   1.33ns ± 6%  0.84ns ± 3%  -36.90%  (p=0.000 n=20+20)
TrailingZeros16-8  1.26ns ± 5%  0.84ns ± 5%  -33.50%  (p=0.000 n=20+18)

Code:

func f8(x uint8)   { z = bits.TrailingZeros8(x) }
func f16(x uint16) { z = bits.TrailingZeros16(x) }

Before:

"".f8 STEXT nosplit size=34 args=0x8 locals=0x0
	0x0000 00000 (x.go:7)	TEXT	"".f8(SB), NOSPLIT, $0-8
	0x0000 00000 (x.go:7)	FUNCDATA	$0, gclocals·2a5305abe05176240e61b8620e19a815(SB)
	0x0000 00000 (x.go:7)	FUNCDATA	$1, gclocals·33cdeccccebe80329f1fdbee7f5874cb(SB)
	0x0000 00000 (x.go:7)	MOVBLZX	"".x+8(SP), AX
	0x0005 00005 (x.go:7)	MOVBLZX	AL, AX
	0x0008 00008 (x.go:7)	BTSQ	$8, AX
	0x000d 00013 (x.go:7)	BSFQ	AX, AX
	0x0011 00017 (x.go:7)	MOVL	$64, CX
	0x0016 00022 (x.go:7)	CMOVQEQ	CX, AX
	0x001a 00026 (x.go:7)	MOVQ	AX, "".z(SB)
	0x0021 00033 (x.go:7)	RET

"".f16 STEXT nosplit size=34 args=0x8 locals=0x0
	0x0000 00000 (x.go:8)	TEXT	"".f16(SB), NOSPLIT, $0-8
	0x0000 00000 (x.go:8)	FUNCDATA	$0, gclocals·2a5305abe05176240e61b8620e19a815(SB)
	0x0000 00000 (x.go:8)	FUNCDATA	$1, gclocals·33cdeccccebe80329f1fdbee7f5874cb(SB)
	0x0000 00000 (x.go:8)	MOVWLZX	"".x+8(SP), AX
	0x0005 00005 (x.go:8)	MOVWLZX	AX, AX
	0x0008 00008 (x.go:8)	BTSQ	$16, AX
	0x000d 00013 (x.go:8)	BSFQ	AX, AX
	0x0011 00017 (x.go:8)	MOVL	$64, CX
	0x0016 00022 (x.go:8)	CMOVQEQ	CX, AX
	0x001a 00026 (x.go:8)	MOVQ	AX, "".z(SB)
	0x0021 00033 (x.go:8)	RET

After:

"".f8 STEXT nosplit size=20 args=0x8 locals=0x0
	0x0000 00000 (x.go:7)	TEXT	"".f8(SB), NOSPLIT, $0-8
	0x0000 00000 (x.go:7)	FUNCDATA	$0, gclocals·2a5305abe05176240e61b8620e19a815(SB)
	0x0000 00000 (x.go:7)	FUNCDATA	$1, gclocals·33cdeccccebe80329f1fdbee7f5874cb(SB)
	0x0000 00000 (x.go:7)	MOVBLZX	"".x+8(SP), AX
	0x0005 00005 (x.go:7)	BTSL	$8, AX
	0x0009 00009 (x.go:7)	BSFL	AX, AX
	0x000c 00012 (x.go:7)	MOVQ	AX, "".z(SB)
	0x0013 00019 (x.go:7)	RET

"".f16 STEXT nosplit size=20 args=0x8 locals=0x0
	0x0000 00000 (x.go:8)	TEXT	"".f16(SB), NOSPLIT, $0-8
	0x0000 00000 (x.go:8)	FUNCDATA	$0, gclocals·2a5305abe05176240e61b8620e19a815(SB)
	0x0000 00000 (x.go:8)	FUNCDATA	$1, gclocals·33cdeccccebe80329f1fdbee7f5874cb(SB)
	0x0000 00000 (x.go:8)	MOVWLZX	"".x+8(SP), AX
	0x0005 00005 (x.go:8)	BTSL	$16, AX
	0x0009 00009 (x.go:8)	BSFL	AX, AX
	0x000c 00012 (x.go:8)	MOVQ	AX, "".z(SB)
	0x0013 00019 (x.go:8)	RET

Change-Id: I0551e357348de2b724737d569afd6ac9f5c3aa11
Reviewed-on: https://go-review.googlesource.com/108940
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Giovanni Bajo <rasky@develer.com>
Reviewed-by: Keith Randall <khr@golang.org>
2018-04-25 21:33:52 +00:00
Russ Cox
90083e658a cmd/go/internal/load: split test logic out of pkg.go into test.go
It's going to grow.

Change-Id: I4f5d3cce6e03250508d1ae0981a6d82a4192ae31
Reviewed-on: https://go-review.googlesource.com/107915
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
2018-04-25 21:01:54 +00:00
Russ Cox
90e860f1a8 cmd/go: add go list -deps
This gives an easy way to query properties of all the deps
of a set of packages, in a single go list invocation.
Go list has already done the hard work of loading these
packages, so exposing them is more efficient than
requiring a second invocation.

This will be helpful for tools asking cmd/go about build
information.

Change-Id: I90798e386246b24aad92dd13cb9e3788c7d30e91
Reviewed-on: https://go-review.googlesource.com/107776
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
2018-04-25 21:01:04 +00:00
Ian Lance Taylor
9c9ed9aa9d misc/cgo/test: log error value in testSigprocmask
The test has been flaky, probably due to EAGAIN, but let's find out
for sure.

Updates #25078

Change-Id: I5a5b14bfc52cb43f25f07ca7d207b61ae9d4f944
Reviewed-on: https://go-review.googlesource.com/109359
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Bryan C. Mills <bcmills@google.com>
2018-04-25 20:26:39 +00:00
Russ Cox
d3ff5090dd cmd/compile: fix format error
Found by pending CL to make cmd/vet auto-detect printf wrappers.

Change-Id: I6b5ba8f9c301dd2d7086c152cf2e54a68b012208
Reviewed-on: https://go-review.googlesource.com/109345
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2018-04-25 20:22:25 +00:00
Russ Cox
50a583966a encoding/base64: fix format error
Found by pending CL to make cmd/vet auto-detect printf wrappers.

Change-Id: I2ad06647b7b41cf68859820a60eeac2e689ca2e6
Reviewed-on: https://go-review.googlesource.com/109344
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2018-04-25 20:22:16 +00:00