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3202 Commits

Author SHA1 Message Date
Matt Juran
e0adc35c47 test: fast GC+concurrency+types verification
This test runs independent goroutines modifying a comprehensive variety
of local vars to look for garbage collector regressions. This test has
been verified to trigger issue 22781 on the go1.9.2 tag. This test
expands on test/fixedbugs/issue22781.go.

Tests #22781

Change-Id: Id32f8dde7ef650aea1b1b4cf518e6d045537bfdc
Reviewed-on: https://go-review.googlesource.com/93715
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-05-08 21:15:48 +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
Matthew Dempsky
004260afde cmd/compile: open code select{send,recv,default}
Registration now looks like:

        var cases [4]runtime.scases
        var order [8]uint16
	cases[0].kind = caseSend
	cases[0].c = c1
	cases[0].elem = &v1
	if raceenabled || msanenabled {
		selectsetpc(&cases[0])
	}
	cases[1].kind = caseRecv
	cases[1].c = c2
	cases[1].elem = &v2
	if raceenabled || msanenabled {
		selectsetpc(&cases[1])
	}
	...

Change-Id: Ib9bcf426a4797fe4bfd8152ca9e6e08e39a70b48
Reviewed-on: https://go-review.googlesource.com/37934
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
2018-05-01 03:17:44 +00:00
Matthew Dempsky
3aa53b3135 runtime: eliminate runtime.hselect
Now the registration phase looks like:

    var cases [4]runtime.scases
    var order [8]uint16
    selectsend(&cases[0], c1, &v1)
    selectrecv(&cases[1], c2, &v2, nil)
    selectrecv(&cases[2], c3, &v3, &ok)
    selectdefault(&cases[3])
    chosen := selectgo(&cases[0], &order[0], 4)

Primarily, this is just preparation for having the compiler open-code
selectsend, selectrecv, and selectdefault.

As a minor benefit, order can now be layed out separately on the stack
in the pointer-free segment, so it won't take up space in the
function's stack pointer maps.

Change-Id: I5552ba594201efd31fcb40084da20b42ea569a45
Reviewed-on: https://go-review.googlesource.com/37933
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
2018-05-01 03:17:31 +00:00
Richard Musiol
e3c684777a all: skip unsupported tests for js/wasm
The general policy for the current state of js/wasm is that it only
has to support tests that are also supported by nacl.

The test nilptr3.go makes assumptions about which nil checks can be
removed. Since WebAssembly does not signal on reading a null pointer,
all nil checks have to be explicit.

Updates #18892

Change-Id: I06a687860b8d22ae26b1c391499c0f5183e4c485
Reviewed-on: https://go-review.googlesource.com/110096
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2018-04-30 19:39:18 +00:00
Giovanni Bajo
e0d37a33ab cmd/compile: teach prove to handle expressions like len(s)-delta
When a loop has bound len(s)-delta, findIndVar detected it and
returned len(s) as (conservative) upper bound. This little lie
allowed loopbce to drop bound checks.

It is obviously more generic to teach prove about relations like
x+d<w for non-constant "w"; we already handled the case for
constant "w", so we just want to learn that if d<0, then x+d<w
proves that x<w.

To be able to remove the code from findIndVar, we also need
to teach prove that len() and cap() are always non-negative.

This CL allows to prove 633 more checks in cmd+std. Most
of them are cases where the code was already testing before
accessing a slice but the compiler didn't know it. For instance,
take strings.HasSuffix:

    func HasSuffix(s, suffix string) bool {
        return len(s) >= len(suffix) && s[len(s)-len(suffix):] == suffix
    }

When suffix is a literal string, the compiler now understands
that the explicit check is enough to not emit a slice check.

I also found a loopbce test that was incorrectly
written to detect an overflow but had a off-by-one (on the
conservative side), so it unexpectly passed with this CL; I
changed it to really trigger the overflow as intended.

Change-Id: Ib5abade337db46b8811425afebad4719b6e46c4a
Reviewed-on: https://go-review.googlesource.com/105635
Run-TryBot: Giovanni Bajo <rasky@develer.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
2018-04-29 09:38:32 +00:00
Giovanni Bajo
6d379add0f cmd/compile: in prove, detect loops with negative increments
To be effective, this also requires being able to relax constraints
on min/max bound inclusiveness; they are now exposed through a flags,
and prove has been updated to handle it correctly.

Change-Id: I3490e54461b7b9de8bc4ae40d3b5e2fa2d9f0556
Reviewed-on: https://go-review.googlesource.com/104041
Run-TryBot: Giovanni Bajo <rasky@develer.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
2018-04-29 09:38:18 +00:00
Giovanni Bajo
980fdb8dd5 cmd/compile: improve testing of induction variables
Test both minimum and maximum bound, and prepare
formatting for more advanced tests (inclusive / esclusive bounds).

Change-Id: Ibe432916d9c938343bc07943798bc9709ad71845
Reviewed-on: https://go-review.googlesource.com/104040
Run-TryBot: Giovanni Bajo <rasky@develer.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-04-29 09:38:09 +00:00
Giovanni Bajo
7ec25d0acf cmd/compile: implement loop BCE in prove
Reuse findIndVar to discover induction variables, and then
register the facts we know about them into the facts table
when entering the loop block.

Moreover, handle "x+delta > w" while updating the facts table,
to be able to prove accesses to slices with constant offsets
such as slice[i-10].

Change-Id: I2a63d050ed58258136d54712ac7015b25c893d71
Reviewed-on: https://go-review.googlesource.com/104038
Run-TryBot: Giovanni Bajo <rasky@develer.com>
Reviewed-by: David Chase <drchase@google.com>
2018-04-29 09:37:35 +00:00
Giovanni Bajo
29162ec9a7 cmd/compile: in prove, infer unsigned relations while branching
When a branch is followed, we apply the relation as described
in the domain relation table. In case the relation is in the
positive domain, we can also infer an unsigned relation if,
by that point, we know that both operands are non-negative.

Fixes #20393

Change-Id: Ieaf0c81558b36d96616abae3eb834c788dd278d5
Reviewed-on: https://go-review.googlesource.com/100278
Run-TryBot: Giovanni Bajo <rasky@develer.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Giovanni Bajo <rasky@develer.com>
Reviewed-by: David Chase <drchase@google.com>
2018-04-29 09:37:15 +00:00
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
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
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
Ilya Tocar
fb017c60bc cmd/compile/internal/ssa: fix endless compile loop on AMD64
We currently rewrite
(TESTQ (MOVQconst [c] x)) into (TESTQconst [c] x)
and (TESTQconst [-1] x) into (TESTQ x x)
if x is a (MOVQconst [-1]) we will be stuck in the endless rewrite loop.
Don't perform the rewrite in such cases.

Fixes #25006

Change-Id: I77f561ba2605fc104f1e5d5c57f32e9d67a2c000
Reviewed-on: https://go-review.googlesource.com/108879
Run-TryBot: Ilya Tocar <ilya.tocar@intel.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2018-04-24 16:20:41 +00:00
Josh Bleecher Snyder
d292f77e95 cmd/compile: rewrite 2*x+c into LEAx1 on amd64
Rewrite x<<1+c into x+x+c, which can be expressed as a single LEAQ/LEAL.

Bit of a special case, but the single-instruction
LEA is both shorter and faster than SHL then ADD.

Triggers 293 times during make.bash.

Change-Id: I3f09c8e9a8f3859d1eeed336f095fc3ada79c2c1
Reviewed-on: https://go-review.googlesource.com/108938
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2018-04-23 22:40:10 +00:00
Josh Bleecher Snyder
566e3e074c cmd/compile: avoid runtime call during switch string(byteslice)
This triggers three times while building std,
once in image/png and twice in go/internal/gccgoimporter.

There are no instances in std in which a more aggressive
optimization would have triggered.

This doesn't necessarily avoid an allocation,
because escape analysis is already able in many cases
to use a temporary backing for the string,
but it does at a minimum avoid the runtime call and copy.

Fixes #24937

Change-Id: I7019e85638ba8cd7e2f03890e672558b858579bc
Reviewed-on: https://go-review.googlesource.com/108035
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2018-04-21 00:50:50 +00:00
Lynn Boger
30311e8860 cmd/compile: generate load without DS relocation for go.string on ppc64le
Due to some recent optimizations related to the compare
instruction, DS-form load instructions started to be used
to load 8-byte go.strings. This can cause link time errors
if the go.string is not aligned to 4 bytes.

For DS-form instructions, the value in the offset field must
be a multiple of 4. If the offset is known at the time the
rules are processed, a DS-form load will not be chosen. But for
go.strings, the offset is not known at that time, but a
relocation is generated indicating that the linker should fill
in the DS relocation. When the linker tries to fill in the
relocation, if the offset is not aligned properly, a link error
will occur.

To fix this, when loading a go.string using MOVDload, the full
address of the go.string is generated and loaded into the base
register. Then the go.string is loaded with a 0 offset field.

Added a testcase that reproduces this problem.

Fixes #24799

Change-Id: I6a154e8e1cba64eae290be0fbcb608b75884ecdd
Reviewed-on: https://go-review.googlesource.com/107855
Run-TryBot: Lynn Boger <laboger@linux.vnet.ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
2018-04-20 16:16:47 +00:00
Ben Shi
34f5f8a580 cmd/compile: optimize ARM64 with register indexed load/store
ARM64 supports load/store instructions with a memory operand that
the address is calculated by base register + index register.

In this CL,
1. Some rules are added to the compile's ARM64 backend to emit
such efficient instructions.
2. A wrong rule of load combination is fixed.

The go1 benchmark does show improvement.

name                     old time/op    new time/op    delta
BinaryTree17-4              44.5s ± 2%     44.1s ± 1%   -0.81%  (p=0.000 n=28+29)
Fannkuch11-4                32.7s ± 3%     30.5s ± 0%   -6.79%  (p=0.000 n=30+26)
FmtFprintfEmpty-4           499ns ± 0%     506ns ± 5%   +1.39%  (p=0.003 n=25+30)
FmtFprintfString-4         1.07µs ± 0%    1.04µs ± 4%   -3.17%  (p=0.000 n=23+30)
FmtFprintfInt-4            1.15µs ± 4%    1.13µs ± 0%   -1.55%  (p=0.000 n=30+23)
FmtFprintfIntInt-4         1.77µs ± 4%    1.74µs ± 0%   -1.71%  (p=0.000 n=30+24)
FmtFprintfPrefixedInt-4    2.37µs ± 5%    2.12µs ± 0%  -10.56%  (p=0.000 n=30+23)
FmtFprintfFloat-4          3.03µs ± 1%    3.03µs ± 4%   -0.13%  (p=0.003 n=25+30)
FmtManyArgs-4              7.38µs ± 1%    7.43µs ± 4%   +0.59%  (p=0.003 n=25+30)
GobDecode-4                 101ms ± 6%      95ms ± 5%   -5.55%  (p=0.000 n=30+30)
GobEncode-4                78.0ms ± 4%    78.8ms ± 6%   +1.05%  (p=0.000 n=30+30)
Gzip-4                      4.25s ± 0%     4.27s ± 4%   +0.45%  (p=0.003 n=24+30)
Gunzip-4                    428ms ± 1%     420ms ± 0%   -1.88%  (p=0.000 n=23+23)
HTTPClientServer-4          549µs ± 1%     541µs ± 1%   -1.56%  (p=0.000 n=29+29)
JSONEncode-4                194ms ± 0%     188ms ± 4%     ~     (p=0.417 n=23+30)
JSONDecode-4                890ms ± 5%     831ms ± 0%   -6.55%  (p=0.000 n=30+23)
Mandelbrot200-4            47.3ms ± 2%    46.5ms ± 0%     ~     (p=0.980 n=30+26)
GoParse-4                  43.1ms ± 6%    43.8ms ± 6%   +1.65%  (p=0.000 n=30+30)
RegexpMatchEasy0_32-4      1.06µs ± 0%    1.07µs ± 3%     ~     (p=0.092 n=23+30)
RegexpMatchEasy0_1K-4      5.53µs ± 0%    5.51µs ± 0%   -0.24%  (p=0.000 n=25+25)
RegexpMatchEasy1_32-4      1.02µs ± 3%    1.01µs ± 0%   -1.27%  (p=0.000 n=30+24)
RegexpMatchEasy1_1K-4      7.26µs ± 0%    7.33µs ± 0%   +0.95%  (p=0.000 n=23+26)
RegexpMatchMedium_32-4     1.84µs ± 7%    1.79µs ± 1%     ~     (p=0.333 n=30+23)
RegexpMatchMedium_1K-4      553µs ± 0%     547µs ± 0%   -1.14%  (p=0.000 n=24+22)
RegexpMatchHard_32-4       30.8µs ± 1%    30.3µs ± 0%   -1.40%  (p=0.000 n=24+24)
RegexpMatchHard_1K-4        928µs ± 0%     929µs ± 5%   +0.12%  (p=0.013 n=23+30)
Revcomp-4                   8.13s ± 4%     6.32s ± 1%  -22.23%  (p=0.000 n=30+23)
Template-4                  899ms ± 6%     854ms ± 1%   -5.01%  (p=0.000 n=30+24)
TimeParse-4                4.66µs ± 4%    4.59µs ± 1%   -1.57%  (p=0.000 n=30+23)
TimeFormat-4               4.58µs ± 0%    4.61µs ± 0%   +0.57%  (p=0.000 n=26+24)
[Geo mean]                  717µs          698µs        -2.55%

name                     old speed      new speed      delta
GobDecode-4              7.63MB/s ± 6%  8.08MB/s ± 5%   +5.88%  (p=0.000 n=30+30)
GobEncode-4              9.85MB/s ± 4%  9.75MB/s ± 6%   -1.04%  (p=0.000 n=30+30)
Gzip-4                   4.56MB/s ± 0%  4.55MB/s ± 4%   -0.36%  (p=0.003 n=24+30)
Gunzip-4                 45.3MB/s ± 1%  46.2MB/s ± 0%   +1.92%  (p=0.000 n=23+23)
JSONEncode-4             10.0MB/s ± 0%  10.4MB/s ± 4%     ~     (p=0.403 n=23+30)
JSONDecode-4             2.18MB/s ± 5%  2.33MB/s ± 0%   +6.91%  (p=0.000 n=30+23)
GoParse-4                1.34MB/s ± 5%  1.32MB/s ± 5%   -1.66%  (p=0.000 n=30+30)
RegexpMatchEasy0_32-4    30.2MB/s ± 0%  29.8MB/s ± 3%     ~     (p=0.099 n=23+30)
RegexpMatchEasy0_1K-4     185MB/s ± 0%   186MB/s ± 0%   +0.24%  (p=0.000 n=25+25)
RegexpMatchEasy1_32-4    31.4MB/s ± 3%  31.8MB/s ± 0%   +1.24%  (p=0.000 n=30+24)
RegexpMatchEasy1_1K-4     141MB/s ± 0%   140MB/s ± 0%   -0.94%  (p=0.000 n=23+26)
RegexpMatchMedium_32-4    541kB/s ± 6%   560kB/s ± 0%   +3.45%  (p=0.000 n=30+23)
RegexpMatchMedium_1K-4   1.85MB/s ± 0%  1.87MB/s ± 0%   +1.08%  (p=0.000 n=24+23)
RegexpMatchHard_32-4     1.04MB/s ± 1%  1.06MB/s ± 1%   +1.48%  (p=0.000 n=24+24)
RegexpMatchHard_1K-4     1.10MB/s ± 0%  1.10MB/s ± 5%   +0.15%  (p=0.004 n=23+30)
Revcomp-4                31.3MB/s ± 4%  40.2MB/s ± 1%  +28.52%  (p=0.000 n=30+23)
Template-4               2.16MB/s ± 6%  2.27MB/s ± 1%   +5.18%  (p=0.000 n=30+24)
[Geo mean]               7.57MB/s       7.79MB/s        +2.98%

fixes #24907

Change-Id: I94afd0e3f53d62a1cf5e452f3dd6daf61be21785
Reviewed-on: https://go-review.googlesource.com/107376
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2018-04-19 15:08:10 +00:00
Cherry Zhang
3042463d61 cmd/compile: in escape analysis, use element type for OIND of slice
The escape analysis models the flow of "content" of X with a
level of "indirection" (OIND node) of X. This content can be
pointer dereference, or slice/string element. For the latter
case, the type of the OIND node should be the element type of
the slice/string. This CL fixes this. In particular, this
matters when the element type is pointerless, where the data
flow should not cause any escape.

Fixes #15730.

Change-Id: Iba9f92898681625e7e3ddef76ae65d7cd61c41e0
Reviewed-on: https://go-review.googlesource.com/107597
Reviewed-by: David Chase <drchase@google.com>
2018-04-18 02:59:37 +00:00
Michael Munday
58cdecb9c8 cmd/compile: generate constants for NeqPtr, EqPtr and IsNonNil ops
If both inputs are constant offsets from the same pointer then we
can evaluate NeqPtr and EqPtr at compile time. Triggers a few times
during all.bash. Removes a conditional branch in the following
code:

copy(x[1:], x[:])

This branch was recently added as an optimization in CL 94596. We
now skip the memmove if the pointers are equal. However, in the
above code we know at compile time that they are never equal.

Also, when the offset is variable, check if the offset is zero
rather than if the pointers are equal. For example:

copy(x[a:], x[:])

This would now skip the copy if a == 0, rather than if x + a == x.

Finally I've also added a rule to make IsNonNil true for pointers
to values on the stack. The nil check elimination pass will catch
these anyway, but eliminating them here might eliminate branches
earlier.

Change-Id: If72f436fef0a96ad0f4e296d3a1f8b6c3e712085
Reviewed-on: https://go-review.googlesource.com/106635
Run-TryBot: Michael Munday <mike.munday@ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2018-04-16 20:43:57 +00:00
Ben Shi
cd65bbc01b cmd/compile/internal/ssa: optimize 386's subtraction
The SUBL instruction can take a memory operand, and this CL
implements this optimization.

The go1 benchmark shows a little improvement.

name                     old time/op    new time/op    delta
BinaryTree17-4              3.27s ± 2%     3.29s ± 3%    ~     (p=0.322 n=37+40)
Fannkuch11-4                3.49s ± 0%     3.53s ± 1%  +1.21%  (p=0.000 n=31+40)
FmtFprintfEmpty-4          46.2ns ± 3%    46.3ns ± 2%    ~     (p=0.351 n=40+28)
FmtFprintfString-4         82.0ns ± 3%    81.5ns ± 2%  -0.69%  (p=0.002 n=40+30)
FmtFprintfInt-4            94.6ns ± 3%    94.6ns ± 6%    ~     (p=0.913 n=39+37)
FmtFprintfIntInt-4          147ns ± 3%     150ns ± 2%  +1.72%  (p=0.000 n=40+25)
FmtFprintfPrefixedInt-4     186ns ± 3%     186ns ± 0%  -0.33%  (p=0.006 n=40+25)
FmtFprintfFloat-4           388ns ± 4%     388ns ± 4%    ~     (p=0.162 n=40+40)
FmtManyArgs-4               612ns ± 3%     616ns ± 4%    ~     (p=0.223 n=40+40)
GobDecode-4                7.35ms ± 5%    7.42ms ± 5%    ~     (p=0.095 n=40+40)
GobEncode-4                7.21ms ± 8%    7.23ms ± 4%    ~     (p=0.294 n=40+40)
Gzip-4                      360ms ± 4%     359ms ± 4%    ~     (p=0.097 n=40+40)
Gunzip-4                   46.1ms ± 3%    45.6ms ± 3%  -1.20%  (p=0.000 n=40+40)
HTTPClientServer-4         64.0µs ± 2%    64.1µs ± 2%    ~     (p=0.648 n=39+40)
JSONEncode-4               21.9ms ± 4%    22.1ms ± 5%    ~     (p=0.086 n=40+40)
JSONDecode-4               67.9ms ± 4%    66.7ms ± 4%  -1.63%  (p=0.000 n=40+40)
Mandelbrot200-4            5.19ms ± 3%    5.17ms ± 3%    ~     (p=0.881 n=40+40)
GoParse-4                  3.34ms ± 3%    3.28ms ± 2%  -1.78%  (p=0.000 n=40+40)
RegexpMatchEasy0_32-4       101ns ± 5%      99ns ± 3%  -2.40%  (p=0.000 n=40+40)
RegexpMatchEasy0_1K-4       851ns ± 1%     848ns ± 3%  -0.36%  (p=0.004 n=33+40)
RegexpMatchEasy1_32-4       109ns ± 5%     105ns ± 3%  -3.53%  (p=0.000 n=39+40)
RegexpMatchEasy1_1K-4      1.03µs ± 4%    1.03µs ± 3%    ~     (p=0.638 n=40+38)
RegexpMatchMedium_32-4      131ns ± 5%     127ns ± 4%  -3.36%  (p=0.000 n=38+40)
RegexpMatchMedium_1K-4     43.4µs ± 4%    43.2µs ± 3%  -0.46%  (p=0.008 n=40+40)
RegexpMatchHard_32-4       2.21µs ± 4%    2.23µs ± 1%  +0.77%  (p=0.014 n=40+28)
RegexpMatchHard_1K-4       67.6µs ± 4%    67.7µs ± 3%  +0.11%  (p=0.016 n=40+40)
Revcomp-4                   1.86s ± 3%     1.77s ± 2%  -4.81%  (p=0.000 n=40+40)
Template-4                 71.7ms ± 3%    71.6ms ± 4%    ~     (p=0.200 n=40+40)
TimeParse-4                 436ns ± 4%     433ns ± 3%    ~     (p=0.358 n=40+40)
TimeFormat-4                413ns ± 4%     412ns ± 3%    ~     (p=0.415 n=40+40)
[Geo mean]                 63.9µs         63.6µs       -0.49%

name                     old speed      new speed      delta
GobDecode-4               105MB/s ± 5%   104MB/s ± 5%    ~     (p=0.096 n=40+40)
GobEncode-4               106MB/s ± 7%   106MB/s ± 3%    ~     (p=0.385 n=39+40)
Gzip-4                   54.0MB/s ± 4%  54.0MB/s ± 4%    ~     (p=0.100 n=40+40)
Gunzip-4                  421MB/s ± 3%   426MB/s ± 3%  +1.21%  (p=0.000 n=40+40)
JSONEncode-4             88.5MB/s ± 5%  88.0MB/s ± 5%    ~     (p=0.083 n=40+40)
JSONDecode-4             28.6MB/s ± 4%  29.1MB/s ± 4%  +1.65%  (p=0.000 n=40+40)
GoParse-4                17.3MB/s ± 3%  17.7MB/s ± 2%  +1.82%  (p=0.000 n=40+40)
RegexpMatchEasy0_32-4     316MB/s ± 5%   323MB/s ± 4%  +2.44%  (p=0.000 n=40+40)
RegexpMatchEasy0_1K-4    1.20GB/s ± 1%  1.21GB/s ± 3%  +0.40%  (p=0.004 n=33+40)
RegexpMatchEasy1_32-4     291MB/s ± 7%   302MB/s ± 4%  +3.82%  (p=0.000 n=40+40)
RegexpMatchEasy1_1K-4     993MB/s ± 4%   990MB/s ± 3%    ~     (p=0.623 n=40+38)
RegexpMatchMedium_32-4   7.61MB/s ± 5%  7.87MB/s ± 4%  +3.36%  (p=0.000 n=38+40)
RegexpMatchMedium_1K-4   23.6MB/s ± 4%  23.7MB/s ± 4%  +0.46%  (p=0.007 n=40+40)
RegexpMatchHard_32-4     14.5MB/s ± 4%  14.3MB/s ± 1%  -0.79%  (p=0.017 n=40+28)
RegexpMatchHard_1K-4     15.1MB/s ± 4%  15.1MB/s ± 3%  -0.11%  (p=0.015 n=40+40)
Revcomp-4                 137MB/s ± 3%   144MB/s ± 3%  +5.06%  (p=0.000 n=40+40)
Template-4               27.1MB/s ± 3%  27.1MB/s ± 4%    ~     (p=0.211 n=40+40)
[Geo mean]               78.9MB/s       79.7MB/s       +1.01%

Change-Id: I638fa4fef85833e8605919d693f9570cc3cf7334
Reviewed-on: https://go-review.googlesource.com/107275
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2018-04-16 04:41:20 +00:00
Giovanni Bajo
e7b1d0a9cf test: add missing copyright header
Change-Id: Ia64535492515f725fe3c4b59ea300363a0c4ce10
Reviewed-on: https://go-review.googlesource.com/107136
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-04-15 21:17:54 +00:00
Giovanni Bajo
2954ef20bb test: small cleanup of code and comments in run.go
While writing CL 107315, I went back and forth for the syntax used for
constraints of build environments in which the architecture did not
support varitants ("plan9/amd64" vs "plan9/amd64/"). I eventually
settled for the latter because the code required less heuristics
(think parsing "plan9/386" vs "386/sse2") but there were a few
leftovers in code and comments.

Change-Id: I9d9a008f3814f9a1642609650eb571e7f1a675cf
Reviewed-on: https://go-review.googlesource.com/107338
Run-TryBot: Giovanni Bajo <rasky@develer.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-04-15 21:17:43 +00:00
Giovanni Bajo
284ba47b49 test: run codegen tests on all supported architecture variants
This CL makes the codegen testsuite automatically test all
architecture variants for architecture specified in tests. For
instance, if a test file specifies a "arm" test, it will be
automatically run on all GOARM variants (5,6,7), to increase
the coverage.

The CL also introduces a syntax to specify only a specific
variant (eg: "arm/7") in case the test makes sense only there.
The same syntax also allows to specify the operating system
in case it matters (eg: "plan9/386/sse2").

Fixes #24658

Change-Id: I2eba8b918f51bb6a77a8431a309f8b71af07ea22
Reviewed-on: https://go-review.googlesource.com/107315
Run-TryBot: Giovanni Bajo <rasky@develer.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-04-15 20:02:43 +00:00
Giovanni Bajo
01aa1d7dbe test: migrate plan9 tests to codegen
And remove it from asmtest. Next CL will remove the whole
asmtest infrastructure.

Change-Id: I5851bf7c617456d62a3c6cffacf70252df7b056b
Reviewed-on: https://go-review.googlesource.com/107335
Run-TryBot: Giovanni Bajo <rasky@develer.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-04-15 20:02:30 +00:00
Cherry Zhang
b08a9b7ecc all: use new softfloat on GOARM=5
Use the new softfloat support in the compiler, originally added
for softfloat on MIPS. This support is portable, so we can just
use it for softfloat on ARM.

In the old softfloat support on ARM, the compiler generates
floating point instructions, then the assembler inserts calls
to _sfloat before FP instructions. _sfloat decodes the following
FP instructions and simulates them.

In the new scheme, the compiler generates runtime calls to do FP
operations at a higher level. It doesn't generate FP instructions,
and therefore the assembler won't insert _sfloat calls, i.e. the
old mechanism is automatically suppressed.

The old method may be still be triggered with assembly code
using FP instructions. In the standard library, the only
occurance is math/sqrt_arm.s, which is rewritten to call to the
Go implementation instead.

Some significant speedups for code using floating points:

name                     old time/op    new time/op     delta
BinaryTree17-4              37.1s ± 2%      37.3s ± 1%     ~     (p=0.105 n=10+10)
Fannkuch11-4                13.0s ± 0%      13.1s ± 0%   +0.46%  (p=0.000 n=10+10)
FmtFprintfEmpty-4           700ns ± 4%      734ns ± 6%   +4.84%  (p=0.009 n=10+10)
FmtFprintfString-4         1.22µs ± 3%     1.22µs ± 4%     ~     (p=0.897 n=10+10)
FmtFprintfInt-4            1.27µs ± 2%     1.30µs ± 1%   +1.91%  (p=0.001 n=10+9)
FmtFprintfIntInt-4         1.83µs ± 2%     1.81µs ± 3%     ~     (p=0.149 n=10+10)
FmtFprintfPrefixedInt-4    1.80µs ± 3%     1.81µs ± 2%     ~     (p=0.421 n=10+8)
FmtFprintfFloat-4          6.89µs ± 3%     3.59µs ± 2%  -47.93%  (p=0.000 n=10+10)
FmtManyArgs-4              6.39µs ± 1%     6.09µs ± 1%   -4.61%  (p=0.000 n=10+9)
GobDecode-4                 109ms ± 2%       81ms ± 2%  -25.99%  (p=0.000 n=9+10)
GobEncode-4                 109ms ± 2%       76ms ± 2%  -29.88%  (p=0.000 n=10+9)
Gzip-4                      3.61s ± 1%      3.59s ± 1%     ~     (p=0.247 n=10+10)
Gunzip-4                    449ms ± 4%      450ms ± 1%     ~     (p=0.230 n=10+7)
HTTPClientServer-4         1.55ms ± 3%     1.53ms ± 2%     ~     (p=0.400 n=9+10)
JSONEncode-4                356ms ± 1%      183ms ± 1%  -48.73%  (p=0.000 n=10+10)
JSONDecode-4                1.12s ± 2%      0.87s ± 1%  -21.88%  (p=0.000 n=10+10)
Mandelbrot200-4             5.49s ± 1%      2.55s ± 1%  -53.45%  (p=0.000 n=9+10)
GoParse-4                  49.6ms ± 2%     47.5ms ± 1%   -4.08%  (p=0.000 n=10+9)
RegexpMatchEasy0_32-4      1.13µs ± 4%     1.20µs ± 4%   +6.42%  (p=0.000 n=10+10)
RegexpMatchEasy0_1K-4      4.41µs ± 2%     4.44µs ± 2%     ~     (p=0.128 n=10+10)
RegexpMatchEasy1_32-4      1.15µs ± 5%     1.20µs ± 5%   +4.85%  (p=0.002 n=10+10)
RegexpMatchEasy1_1K-4      6.21µs ± 2%     6.37µs ± 4%   +2.62%  (p=0.001 n=9+10)
RegexpMatchMedium_32-4     1.58µs ± 5%     1.65µs ± 3%   +4.85%  (p=0.000 n=10+10)
RegexpMatchMedium_1K-4      341µs ± 3%      351µs ± 7%     ~     (p=0.573 n=8+10)
RegexpMatchHard_32-4       21.4µs ± 3%     21.5µs ± 5%     ~     (p=0.931 n=9+9)
RegexpMatchHard_1K-4        626µs ± 2%      626µs ± 1%     ~     (p=0.645 n=8+8)
Revcomp-4                  46.4ms ± 2%     47.4ms ± 2%   +2.07%  (p=0.000 n=10+10)
Template-4                  1.31s ± 3%      1.23s ± 4%   -6.13%  (p=0.000 n=10+10)
TimeParse-4                4.49µs ± 1%     4.41µs ± 2%   -1.81%  (p=0.000 n=10+9)
TimeFormat-4               9.31µs ± 1%     9.32µs ± 2%     ~     (p=0.561 n=9+9)

Change-Id: Iaeeff6c9a09c1b2c064d06e09dd88101dc02bfa4
Reviewed-on: https://go-review.googlesource.com/106735
Reviewed-by: Austin Clements <austin@google.com>
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2018-04-13 16:39:39 +00:00
Cherry Zhang
5a91c83ce8 cmd/compile: in escape analysis, propagate loop depth to field
The escape analysis models "loop depth". If the address of an
expression is assigned to something defined at a lower (outer)
loop depth, the escape analysis decides it escapes. However, it
uses the loop depth of the address operator instead of where
the RHS is defined. This causes an unnecessary escape if there is
an assignment inside a loop but the RHS is defined outside the
loop. This CL propagates the loop depth.

Fixes #24730.

Change-Id: I5ff1530688bdfd90561a7b39c8be9bfc009a9dae
Reviewed-on: https://go-review.googlesource.com/105257
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
2018-04-13 14:48:23 +00:00
Josh Bleecher Snyder
c1ed1f3c80 cmd/compile: fix evaluation of "" < s
Fixes #24817

Change-Id: Ifa79ab3dfe69297eeef85f7193cd5f85e5982bc5
Reviewed-on: https://go-review.googlesource.com/106655
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2018-04-12 19:38:37 +00:00
Josh Bleecher Snyder
2dfb423e6e cmd/compile: loop to ensure all autogenerated functions are compiled
I was wrong. There was a need to loop here.

Fixes #24761

Change-Id: If13b3ab72febde930bdaebdddd1c05e0d0446020
Reviewed-on: https://go-review.googlesource.com/105615
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2018-04-11 23:46:30 +00:00
Alberto Donizetti
467eca6076 test/codegen: port last stack and memcombining tests
And delete them from asm_test.

Also delete an arm64 cmov test has been already ported to the new test
harness.

Change-Id: I4458721e1f512bc9ecbbe1c22a2c9c7109ad68fe
Reviewed-on: https://go-review.googlesource.com/106335
Run-TryBot: Alberto Donizetti <alb.donizetti@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Giovanni Bajo <rasky@develer.com>
2018-04-11 16:08:04 +00:00
Robert Griesemer
3d501df441 cmd/compile: better error message when referring to ambiguous method/field
Fixes #14321.

Change-Id: I9c92c767b01cf7938c4808a8fef9f2936fc667bc
Reviewed-on: https://go-review.googlesource.com/106119
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2018-04-10 23:39:13 +00:00
Matthew Dempsky
535ad8efb8 cmd/compile: fix check that ensures main.main is a function
The check was previously disallowing package main from even importing
a non-function symbol named "main".

Fixes #24801.

Change-Id: I849b9713890429f0a16860ef16b5dc7e970d04a4
Reviewed-on: https://go-review.googlesource.com/106120
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
2018-04-10 23:34:12 +00:00
Alberto Donizetti
188e2bf897 test/codegen: port arm64 BIC/EON/ORN and masking tests
And delete them from asm_test.

Change-Id: I24f421b87e8cb4770c887a6dfd58eacd0088947d
Reviewed-on: https://go-review.googlesource.com/106056
Reviewed-by: Keith Randall <khr@golang.org>
2018-04-10 10:57:50 +00:00
Alberto Donizetti
d5ff631e6b test/codegen: port last remaining misc bit/arithmetic tests
And delete them from asm_test.

Change-Id: I9a75efe9858ef9d7ac86065f860c2ae3f25b0941
Reviewed-on: https://go-review.googlesource.com/105597
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>
2018-04-10 07:58:35 +00:00
Matthew Dempsky
49ed4cbe85 cmd/compile: sort method sets using package height
Also, when statically building itabs, compare *types.Sym instead of
name alone so that method sets with duplicate non-exported methods are
handled correctly.

Fixes #24693.

Change-Id: I2db8a3d6e80991a71fef5586a15134b6de116269
Reviewed-on: https://go-review.googlesource.com/105039
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
2018-04-10 00:06:06 +00:00
Matthew Dempsky
fe77a5413e cmd/compile: fix constant pointer comparison failure
Previously, constant pointer-typed expressions could use either Mpint
or NilVal as their Val depending on their construction, but const.go
expects each type to have a single corresponding Val kind.

This CL changes pointer-typed expressions to exclusively use Mpint.

Fixes #21221.

Change-Id: I6ba36c9b11eb19a68306f0b296acb11a8c254c41
Reviewed-on: https://go-review.googlesource.com/105315
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
2018-04-09 23:19:45 +00:00
Michael Munday
b65122f99a cmd/compile: optimize comparisons using load merging where available
Multi-byte comparison operations were used on amd64, arm64, i386
and s390x for comparisons with constant arrays, but only amd64 and
i386 for comparisons with string constants. This CL combines the
check for platform capability, since they have the same requirements,
and also enables both on ppc64le which also supports load merging.

Note that these optimizations currently use little endian byte order
which results in byte reversal instructions on s390x. This should
be fixed at some point.

Change-Id: Ie612d13359b50c77f4d7c6e73fea4a59fa11f322
Reviewed-on: https://go-review.googlesource.com/102558
Run-TryBot: Michael Munday <mike.munday@ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2018-04-09 21:16:47 +00:00
Keith Randall
0de0ed369f test: check that unaligned load-add opcodes work.
A test for CL 102036.

Change-Id: Ief6dcb4f478670813fbe22ea75a06815a4b201a3
Reviewed-on: https://go-review.googlesource.com/105875
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2018-04-09 18:57:37 +00:00
Alberto Donizetti
54c3f56ee0 test/codegen: port various mem-combining tests
And delete them from asm_test.

Change-Id: I0e33d58274951ab5acb67b0117b60ef617ea887a
Reviewed-on: https://go-review.googlesource.com/105735
Run-TryBot: Alberto Donizetti <alb.donizetti@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>
2018-04-09 12:00:06 +00:00
Alberto Donizetti
3e31eb6b84 test/codegen: port arm64 slice zeroing tests
Finish porting arm64 slice zeroing codegen tests; delete them from
asm_test.

Change-Id: Id2532df8ba1c340fa662a6b5238daa3de30548be
Reviewed-on: https://go-review.googlesource.com/105136
Run-TryBot: Alberto Donizetti <alb.donizetti@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Giovanni Bajo <rasky@develer.com>
2018-04-07 09:55:51 +00:00
Matthew Dempsky
950a56899a cmd/compile: fix method expressions with anonymous receivers
Method expressions with anonymous receiver types like "struct { T }.m"
require wrapper functions, which we weren't always creating. This in
turn resulted in linker errors.

This CL ensures that we generate wrapper functions for any anonymous
receiver types used in a method expression.

Fixes #22444.

Change-Id: Ia8ac27f238c2898965e57b82a91d959792d2ddd4
Reviewed-on: https://go-review.googlesource.com/105044
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-04-06 15:39:11 +00:00
Matthew Dempsky
638f112d69 cmd/compile: cleanup method symbol creation
There were multiple ad hoc ways to create method symbols, with subtle
and confusing differences between them. This CL unifies them into a
single well-documented encoding and implementation.

This introduces some inconsequential changes to symbol format for the
sake of simplicity and consistency. Two notable changes:

1) Symbol construction is now insensitive to the package currently
being compiled. Previously, non-exported methods on anonymous types
received different method symbols depending on whether the method was
local or imported.

2) Symbols for method values parenthesized non-pointer receiver types
and non-exported method names, and also always package-qualified
non-exported method names. Now they use the same rules as normal
method symbols.

The methodSym function is also now stricter about rejecting
non-sensical method/receiver combinations. Notably, this means that
typecheckfunc needs to call addmethod to validate the method before
calling declare, which also means we no longer emit errors about
redeclaring bogus methods.

Change-Id: I9501c7a53dd70ef60e5c74603974e5ecc06e2003
Reviewed-on: https://go-review.googlesource.com/104876
Reviewed-by: Robert Griesemer <gri@golang.org>
2018-04-05 22:01:17 +00:00
Daniel Martí
9767727353 test: skip locklinear's lockmany test for now
Since it's been reliably failing on one of the linux-arm builders
(arm5spacemonkey) for a long time.

Updates #24221.

Change-Id: I8fccc7e16631de497ccc2c285e510a110a93ad95
Reviewed-on: https://go-review.googlesource.com/104535
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-04-05 10:53:40 +00:00
Alberto Donizetti
f2abca90a2 test/codegen: port arm64 byte slice zeroing tests
And delete them from asm_test.

Change-Id: Id533130470da9176a401cb94972f626f43a62148
Reviewed-on: https://go-review.googlesource.com/103656
Run-TryBot: Alberto Donizetti <alb.donizetti@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Giovanni Bajo <rasky@develer.com>
2018-04-04 13:18:15 +00:00
Robert Griesemer
4637699e92 cmd/compile/internal/syntax: better error message for incorrect if/switch header
Fixes #23664.

Change-Id: Ic0637e9f896b2fc6502dfbab2d1c4de3c62c0bd2
Reviewed-on: https://go-review.googlesource.com/104616
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Run-TryBot: Robert Griesemer <gri@golang.org>
2018-04-03 21:57:37 +00:00
Giovanni Bajo
ac43de3ae5 cmd/compile: in prove, complete support for OpIsInBounds/OpIsSliceInBounds
The logic in addBranchRestrictions didn't allow to correctly
model OpIs(Slice)Bound for signed domain, and it was also partly
implemented within addRestrictions.

Thanks to the previous changes, it is now possible to handle
the negative conditions correctly, so that we can learn
both signed/LT + unsigned/LT on the positive side, and
signed/GE + unsigned/GE on the negative side (but only if
the index can be proved to be non-negative).

This is able to prove ~50 more slice accesses in std+cmd.

Change-Id: I9858080dc03b16f85993a55983dbc4b00f8491b0
Reviewed-on: https://go-review.googlesource.com/104037
Run-TryBot: Giovanni Bajo <rasky@develer.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
2018-04-03 20:25:34 +00:00
isharipo
dcaf3fb134 cmd/compile: make DCE remove nodes after terminating if
This change makes compiler frontend dead code elimination of const expr if
statements introduced in https://golang.org/cl/38773 treat both
	if constCondTrue { ...; returnStmt } toBeRemoved...
	if constCondFalse { ...; } else { returnStmt } toBeRemoved...
identically to:
	if constCondTrue { ...; returnStmt } else { toBeRemoved... }

Where "constCondTrue" is a an expression that can be evaluated
to "true" during compile time.

The additional checks are only triggered for const expr
if conditions that evaluate to true.

name       old time/op       new time/op       delta
Template         431ms ± 2%        429ms ± 1%    ~     (p=0.491 n=8+6)
Unicode          198ms ± 4%        201ms ± 2%    ~     (p=0.234 n=7+6)
GoTypes          1.40s ± 1%        1.41s ± 2%    ~     (p=0.053 n=7+7)
Compiler         6.72s ± 2%        6.81s ± 1%  +1.35%  (p=0.011 n=7+7)
SSA              17.3s ± 1%        17.3s ± 2%    ~     (p=0.731 n=6+7)
Flate            275ms ± 2%        275ms ± 2%    ~     (p=0.902 n=7+7)
GoParser         340ms ± 2%        339ms ± 2%    ~     (p=0.902 n=7+7)
Reflect          910ms ± 2%        905ms ± 1%    ~     (p=0.310 n=6+6)
Tar              403ms ± 1%        403ms ± 2%    ~     (p=0.366 n=7+6)
XML              486ms ± 1%        490ms ± 1%    ~     (p=0.065 n=6+6)
StdCmd           56.2s ± 1%        56.6s ± 2%    ~     (p=0.620 n=7+7)

name       old user-time/op  new user-time/op  delta
Template         559ms ± 8%        557ms ± 7%    ~     (p=0.713 n=8+7)
Unicode          266ms ±13%        277ms ± 9%    ~     (p=0.157 n=8+7)
GoTypes          1.83s ± 2%        1.84s ± 1%    ~     (p=0.522 n=8+7)
Compiler         8.67s ± 4%        8.89s ± 4%    ~     (p=0.077 n=7+7)
SSA              23.9s ± 1%        24.2s ± 1%  +1.31%  (p=0.005 n=7+7)
Flate            351ms ± 4%        342ms ± 5%    ~     (p=0.105 n=7+7)
GoParser         437ms ± 2%        423ms ± 5%  -3.14%  (p=0.016 n=7+7)
Reflect          1.16s ± 3%        1.15s ± 2%    ~     (p=0.362 n=7+7)
Tar              517ms ± 4%        511ms ± 3%    ~     (p=0.538 n=7+7)
XML              619ms ± 3%        617ms ± 4%    ~     (p=0.483 n=7+7)

Fixes #23521

Change-Id: I165a7827d869aeb93ce6047d026ff873d039a4f3
Reviewed-on: https://go-review.googlesource.com/91056
Run-TryBot: Iskander Sharipov <iskander.sharipov@intel.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
2018-04-03 15:19:41 +00:00
Robert Griesemer
c65a2781be cmd/compile: better handling of incorrect type switches
Don't report errors if we don't have a correct type switch
guard; instead ignore it and leave it to the type-checker
to report the error. This leads to better error messages
concentrating on the type switch guard rather than errors
around (confusing) syntactic details.

Also clean up some code setting up AssertExpr (they never
have a nil Type field) and remove some incorrect TODOs.

Fixes #24470.

Change-Id: I69512f36e0417e3b5ea9c8856768e04b19d654a8
Reviewed-on: https://go-review.googlesource.com/103615
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2018-04-03 05:34:20 +00:00
isharipo
b44e73eacb test/fixedbugs: fix bug248 and bug345
When test/run script was removed, these two tests
were changed to be executed by test/run.go.
Because errchk does not exit with non-zero status on
errors, they were silently failing for a while.

This change makes 2 things:

1. Compile tested packages in GOROOT/test to match older runner script
   behavior (strictly required only in bug345, optional in bug248)

2. Check command output with "(?m)^BUG" regexp.
   It approximates older `grep -q '^BUG' that was used before.

See referenced issue for detailed explanation.

Fixes #24629

Change-Id: Ie888dcdb4e25cdbb19d434bbc5cb03eb633e9ee8
Reviewed-on: https://go-review.googlesource.com/104095
Run-TryBot: Iskander Sharipov <iskander.sharipov@intel.com>
Reviewed-by: Emmanuel Odeke <emm.odeke@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2018-04-02 20:08:27 +00:00
Bryan Chan
625f2dccd4 cmd/compile/internal/ssa: handle symbol address comparisons consistently
CL 38338 introduced SSA rules to optimize two types of pointer equality
tests: a pointer compared with itself, and comparison of addresses taken
of two symbols which may have the same base. This patch adds rules to
apply the same optimization to pointer inequality tests, which also ensures
that two pointers to zero-width types cannot be both equal and unequal
at the same time.

Fixes #24503.

Change-Id: Ic828aeb86ae2e680caf66c35f4c247674768a9ba
Reviewed-on: https://go-review.googlesource.com/102275
Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2018-03-31 21:37:13 +00:00
Alberto Donizetti
3b0b8bcd68 test/codegen: port stack-related tests to codegen
And delete them from asm_test.

Change-Id: Idfe1249052d82d15b9c30b292c78656a0bf7b48d
Reviewed-on: https://go-review.googlesource.com/103315
Run-TryBot: Alberto Donizetti <alb.donizetti@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2018-03-30 08:08:06 +00:00
Alberto Donizetti
56eaf574a1 test/codegen: match 387 ops too for GOARCH=386
Change-Id: I99407e27e340689009af798989b33cef7cb92070
Reviewed-on: https://go-review.googlesource.com/103376
Run-TryBot: Alberto Donizetti <alb.donizetti@gmail.com>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2018-03-29 20:05:40 +00:00
Alberto Donizetti
aacf7a1846 test: avoid touching GOOS/GOARCH in codegen driver
This change modifies the codegen test harness driver so that it no
longer modifies the environment GOOS/GOARCH, since that seems to cause
flakiness in other concurrently-running tests.

The change also enables the codegen tests in run.go.

Fixes #24538

Change-Id: I997ac1eb38eb92054efff67fe5c4d3cccc86412b
Reviewed-on: https://go-review.googlesource.com/103455
Run-TryBot: Alberto Donizetti <alb.donizetti@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2018-03-29 19:00:10 +00:00
Alberto Donizetti
04e993f953 test: update list of escape reasons
The escape_because.go test file (which tests the "because" escape
explainations printed by `-m -m`) cointains a machine-generated list
of all the escape reasons seen in the escape tests.

The list appears to be outdated; moreove a new escape reason was added
in CL 102895. This change re-generates the list.

Change-Id: Idc721c6bbfe9516895b5cf1e6d09b77deda5a3dd
Reviewed-on: https://go-review.googlesource.com/103375
Reviewed-by: David Chase <drchase@google.com>
Run-TryBot: Alberto Donizetti <alb.donizetti@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2018-03-29 14:17:40 +00:00
Alberto Donizetti
360c19157a cmd/compile: print accurate escape reason for non-const-length slices
This change makes `-m -m` print a better explanation for the case
where a slice is marked as escaping and heap-allocated because it
has a non-constant len/cap.

Fixes #24578

Change-Id: I0ebafb77c758a99857d72b365817bdba7b446cc0
Reviewed-on: https://go-review.googlesource.com/102895
Reviewed-by: David Chase <drchase@google.com>
Reviewed-by: Ilya Tocar <ilya.tocar@intel.com>
2018-03-28 16:56:03 +00:00
Matthew Dempsky
7b177b1a03 cmd/compile: fix method set computation for shadowed methods
In expandmeth, we call expand1/expand0 to build a list of all
candidate methods to promote, and then we use dotpath to prune down
which names actually resolve to a promoted method and how.

However, previously we still computed "followsptr" based on the
expand1/expand0 traversal (which is depth-first), rather than
dotpath (which is breadth-first). The result is that we could
sometimes end up miscomputing whether a particular promoted method
involves a pointer traversal, which could result in bad code
generation for method trampolines.

Fixes #24547.

Change-Id: I57dc014466d81c165b05d78b98610dc3765b7a90
Reviewed-on: https://go-review.googlesource.com/102618
Reviewed-by: Robert Griesemer <gri@golang.org>
2018-03-27 18:56:36 +00:00
Alberto Donizetti
a27cd4fd31 test/codegen: port tbz/tbnz arm64 tests
And delete them from asm_test.

Change-Id: I34fcf85ae8ce09cd146fe4ce6a0ae7616bd97e2d
Reviewed-on: https://go-review.googlesource.com/102296
Run-TryBot: Alberto Donizetti <alb.donizetti@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Giovanni Bajo <rasky@develer.com>
2018-03-24 09:35:53 +00:00
Giovanni Bajo
79112707bb cmd/compile: add patterns for bit set/clear/complement on amd64
This patch completes implementation of BT(Q|L), and adds support
for BT(S|R|C)(Q|L).

Example of code changes from time.(*Time).addSec:

        if t.wall&hasMonotonic != 0 {
  0x1073465               488b08                  MOVQ 0(AX), CX
  0x1073468               4889ca                  MOVQ CX, DX
  0x107346b               48c1e93f                SHRQ $0x3f, CX
  0x107346f               48c1e13f                SHLQ $0x3f, CX
  0x1073473               48f7c1ffffffff          TESTQ $-0x1, CX
  0x107347a               746b                    JE 0x10734e7

        if t.wall&hasMonotonic != 0 {
  0x1073435               488b08                  MOVQ 0(AX), CX
  0x1073438               480fbae13f              BTQ $0x3f, CX
  0x107343d               7363                    JAE 0x10734a2

Another example:

                        t.wall = t.wall&nsecMask | uint64(dsec)<<nsecShift | hasMonotonic
  0x10734c8               4881e1ffffff3f          ANDQ $0x3fffffff, CX
  0x10734cf               48c1e61e                SHLQ $0x1e, SI
  0x10734d3               4809ce                  ORQ CX, SI
  0x10734d6               48b90000000000000080    MOVQ $0x8000000000000000, CX
  0x10734e0               4809f1                  ORQ SI, CX
  0x10734e3               488908                  MOVQ CX, 0(AX)

                        t.wall = t.wall&nsecMask | uint64(dsec)<<nsecShift | hasMonotonic
  0x107348b		4881e2ffffff3f		ANDQ $0x3fffffff, DX
  0x1073492		48c1e61e		SHLQ $0x1e, SI
  0x1073496		4809f2			ORQ SI, DX
  0x1073499		480fbaea3f		BTSQ $0x3f, DX
  0x107349e		488910			MOVQ DX, 0(AX)

Go1 benchmarks seem unaffected, and I would be surprised
otherwise:

name                     old time/op    new time/op     delta
BinaryTree17-4              2.64s ± 4%      2.56s ± 9%  -2.92%  (p=0.008 n=9+9)
Fannkuch11-4                2.90s ± 1%      2.95s ± 3%  +1.76%  (p=0.010 n=10+9)
FmtFprintfEmpty-4          35.3ns ± 1%     34.5ns ± 2%  -2.34%  (p=0.004 n=9+8)
FmtFprintfString-4         57.0ns ± 1%     58.4ns ± 5%  +2.52%  (p=0.029 n=9+10)
FmtFprintfInt-4            59.8ns ± 3%     59.8ns ± 6%    ~     (p=0.565 n=10+10)
FmtFprintfIntInt-4         93.9ns ± 3%     91.2ns ± 5%  -2.94%  (p=0.014 n=10+9)
FmtFprintfPrefixedInt-4     107ns ± 6%      104ns ± 6%    ~     (p=0.099 n=10+10)
FmtFprintfFloat-4           187ns ± 3%      188ns ± 3%    ~     (p=0.505 n=10+9)
FmtManyArgs-4               410ns ± 1%      415ns ± 6%    ~     (p=0.649 n=8+10)
GobDecode-4                5.30ms ± 3%     5.27ms ± 3%    ~     (p=0.436 n=10+10)
GobEncode-4                4.62ms ± 5%     4.47ms ± 2%  -3.24%  (p=0.001 n=9+10)
Gzip-4                      197ms ± 4%      193ms ± 3%    ~     (p=0.123 n=10+10)
Gunzip-4                   30.4ms ± 3%     30.1ms ± 3%    ~     (p=0.481 n=10+10)
HTTPClientServer-4         76.3µs ± 1%     76.0µs ± 1%    ~     (p=0.236 n=8+9)
JSONEncode-4               10.5ms ± 9%     10.3ms ± 3%    ~     (p=0.280 n=10+10)
JSONDecode-4               42.3ms ±10%     41.3ms ± 2%    ~     (p=0.053 n=9+10)
Mandelbrot200-4            3.80ms ± 2%     3.72ms ± 2%  -2.15%  (p=0.001 n=9+10)
GoParse-4                  2.88ms ±10%     2.81ms ± 2%    ~     (p=0.247 n=10+10)
RegexpMatchEasy0_32-4      69.5ns ± 4%     68.6ns ± 2%    ~     (p=0.171 n=10+10)
RegexpMatchEasy0_1K-4       165ns ± 3%      162ns ± 3%    ~     (p=0.137 n=10+10)
RegexpMatchEasy1_32-4      65.7ns ± 6%     64.4ns ± 2%  -2.02%  (p=0.037 n=10+10)
RegexpMatchEasy1_1K-4       278ns ± 2%      279ns ± 3%    ~     (p=0.991 n=8+9)
RegexpMatchMedium_32-4     99.3ns ± 3%     98.5ns ± 4%    ~     (p=0.457 n=10+9)
RegexpMatchMedium_1K-4     30.1µs ± 1%     30.4µs ± 2%    ~     (p=0.173 n=8+10)
RegexpMatchHard_32-4       1.40µs ± 2%     1.41µs ± 4%    ~     (p=0.565 n=10+10)
RegexpMatchHard_1K-4       42.5µs ± 1%     41.5µs ± 3%  -2.13%  (p=0.002 n=8+9)
Revcomp-4                   332ms ± 4%      328ms ± 5%    ~     (p=0.720 n=9+10)
Template-4                 48.3ms ± 2%     49.6ms ± 3%  +2.56%  (p=0.002 n=8+10)
TimeParse-4                 252ns ± 2%      249ns ± 3%    ~     (p=0.116 n=9+10)
TimeFormat-4                262ns ± 4%      252ns ± 3%  -4.01%  (p=0.000 n=9+10)

name                     old speed      new speed       delta
GobDecode-4               145MB/s ± 3%    146MB/s ± 3%    ~     (p=0.436 n=10+10)
GobEncode-4               166MB/s ± 5%    172MB/s ± 2%  +3.28%  (p=0.001 n=9+10)
Gzip-4                   98.6MB/s ± 4%  100.4MB/s ± 3%    ~     (p=0.123 n=10+10)
Gunzip-4                  639MB/s ± 3%    645MB/s ± 3%    ~     (p=0.481 n=10+10)
JSONEncode-4              185MB/s ± 8%    189MB/s ± 3%    ~     (p=0.280 n=10+10)
JSONDecode-4             46.0MB/s ± 9%   47.0MB/s ± 2%  +2.21%  (p=0.046 n=9+10)
GoParse-4                20.1MB/s ± 9%   20.6MB/s ± 2%    ~     (p=0.239 n=10+10)
RegexpMatchEasy0_32-4     460MB/s ± 4%    467MB/s ± 2%    ~     (p=0.165 n=10+10)
RegexpMatchEasy0_1K-4    6.19GB/s ± 3%   6.28GB/s ± 3%    ~     (p=0.165 n=10+10)
RegexpMatchEasy1_32-4     487MB/s ± 5%    497MB/s ± 2%  +2.00%  (p=0.043 n=10+10)
RegexpMatchEasy1_1K-4    3.67GB/s ± 2%   3.67GB/s ± 3%    ~     (p=0.963 n=8+9)
RegexpMatchMedium_32-4   10.1MB/s ± 3%   10.1MB/s ± 4%    ~     (p=0.435 n=10+9)
RegexpMatchMedium_1K-4   34.0MB/s ± 1%   33.7MB/s ± 2%    ~     (p=0.173 n=8+10)
RegexpMatchHard_32-4     22.9MB/s ± 2%   22.7MB/s ± 4%    ~     (p=0.565 n=10+10)
RegexpMatchHard_1K-4     24.0MB/s ± 3%   24.7MB/s ± 3%  +2.64%  (p=0.001 n=9+9)
Revcomp-4                 766MB/s ± 4%    775MB/s ± 5%    ~     (p=0.720 n=9+10)
Template-4               40.2MB/s ± 2%   39.2MB/s ± 3%  -2.47%  (p=0.002 n=8+10)

The rules match ~1800 times during all.bash.

Fixes #18943

Change-Id: I64be1ada34e89c486dfd935bf429b35652117ed4
Reviewed-on: https://go-review.googlesource.com/94766
Run-TryBot: Giovanni Bajo <rasky@develer.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2018-03-24 02:38:50 +00:00
Alberto Donizetti
fc6280d4b0 test/codegen: port direct comparisons with memory tests
And remove them from asm_test.

Change-Id: I1ca29b40546d6de06f20bfd550ed8ff87f495454
Reviewed-on: https://go-review.googlesource.com/102115
Run-TryBot: Alberto Donizetti <alb.donizetti@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2018-03-22 17:20:09 +00:00
Alberto Donizetti
be371edd67 test/codegen: port comparisons tests to codegen
And delete them from asm_test.

Change-Id: I64c512bfef3b3da6db5c5d29277675dade28b8ab
Reviewed-on: https://go-review.googlesource.com/101595
Run-TryBot: Alberto Donizetti <alb.donizetti@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Giovanni Bajo <rasky@develer.com>
2018-03-20 19:38:06 +00:00
Michael Munday
ae10914e67 cmd/compile: mark LAA and LAAG as clobbering flags on s390x
The atomic add instructions modify the condition code and so need to
be marked as clobbering flags.

Fixes #24449.

Change-Id: Ic69c8d775fbdbfb2a56c5e0cfca7a49c0d7f6897
Reviewed-on: https://go-review.googlesource.com/101455
Run-TryBot: Michael Munday <mike.munday@ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-03-20 09:44:50 +00:00
Vladimir Kuzmin
c12b185a6e cmd/compile: avoid mapaccess at m[k]=append(m[k]..
Currently rvalue m[k] is transformed during walk into:

        tmp1 := *mapaccess(m, k)
        tmp2 := append(tmp1, ...)
        *mapassign(m, k) = tmp2

However, this is suboptimal, as we could instead produce just:
        tmp := mapassign(m, k)
        *tmp := append(*tmp, ...)

Optimization is possible only if during Order it may tell that m[k] is
exactly the same at left and right part of assignment. It doesn't work:
1) m[f(k)] = append(m[f(k)], ...)
2) sink, m[k] = sink, append(m[k]...)
3) m[k] = append(..., m[k],...)

Benchmark:
name                           old time/op    new time/op    delta
MapAppendAssign/Int32/256-8      33.5ns ± 3%    22.4ns ±10%  -33.24%  (p=0.000 n=16+18)
MapAppendAssign/Int32/65536-8    68.2ns ± 6%    48.5ns ±29%  -28.90%  (p=0.000 n=20+20)
MapAppendAssign/Int64/256-8      34.3ns ± 4%    23.3ns ± 5%  -32.23%  (p=0.000 n=17+18)
MapAppendAssign/Int64/65536-8    65.9ns ± 7%    61.2ns ±19%   -7.06%  (p=0.002 n=18+20)
MapAppendAssign/Str/256-8         116ns ±12%      79ns ±16%  -31.70%  (p=0.000 n=20+19)
MapAppendAssign/Str/65536-8       134ns ±15%     111ns ±45%  -16.95%  (p=0.000 n=19+20)

name                           old alloc/op   new alloc/op   delta
MapAppendAssign/Int32/256-8       47.0B ± 0%     46.0B ± 0%   -2.13%  (p=0.000 n=19+18)
MapAppendAssign/Int32/65536-8     27.0B ± 0%     20.7B ±30%  -23.33%  (p=0.000 n=20+20)
MapAppendAssign/Int64/256-8       47.0B ± 0%     46.0B ± 0%   -2.13%  (p=0.000 n=20+17)
MapAppendAssign/Int64/65536-8     27.0B ± 0%     27.0B ± 0%     ~     (all equal)
MapAppendAssign/Str/256-8         94.0B ± 0%     78.0B ± 0%  -17.02%  (p=0.000 n=20+16)
MapAppendAssign/Str/65536-8       54.0B ± 0%     54.0B ± 0%     ~     (all equal)

Fixes #24364
Updates #5147

Change-Id: Id257d052b75b9a445b4885dc571bf06ce6f6b409
Reviewed-on: https://go-review.googlesource.com/100838
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2018-03-20 01:47:07 +00:00
Alberto Donizetti
5a4e09837c test/codegen: port maps test to codegen
And delete them from asm_test.

Change-Id: I3cf0934706a640136cb0f646509174f8c1bf3363
Reviewed-on: https://go-review.googlesource.com/101395
Run-TryBot: Alberto Donizetti <alb.donizetti@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Giovanni Bajo <rasky@develer.com>
2018-03-19 13:39:34 +00:00
Alberto Donizetti
b61b1d2c57 test/codegen: port structs test to codegen
And delete them from asm_test.

Change-Id: Ia286239a3d8f3915f2ca25dbcb39f3354a4f8aea
Reviewed-on: https://go-review.googlesource.com/101138
Run-TryBot: Alberto Donizetti <alb.donizetti@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2018-03-18 16:53:53 +00:00
Alberto Donizetti
cceee685be test/codegen: port floats tests to codegen
And delete them from asm_test.

Change-Id: Ibdaca3496eefc73c731b511ddb9636a1f3dff68c
Reviewed-on: https://go-review.googlesource.com/100915
Run-TryBot: Alberto Donizetti <alb.donizetti@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2018-03-15 18:05:59 +00:00
Giovanni Bajo
a35ec9a59e cmd/compile: implement CMOV on amd64
This builds upon the branchelim pass, activating it for amd64 and
lowering CondSelect. Special care is made to FPU instructions for
NaN handling.

Benchmark results on Xeon E5630 (Westmere EP):

name                      old time/op    new time/op    delta
BinaryTree17-16              4.99s ± 9%     4.66s ± 2%     ~     (p=0.095 n=5+5)
Fannkuch11-16                4.93s ± 3%     5.04s ± 2%     ~     (p=0.548 n=5+5)
FmtFprintfEmpty-16          58.8ns ± 7%    61.4ns ±14%     ~     (p=0.579 n=5+5)
FmtFprintfString-16          114ns ± 2%     114ns ± 4%     ~     (p=0.603 n=5+5)
FmtFprintfInt-16             181ns ± 4%     125ns ± 3%  -30.90%  (p=0.008 n=5+5)
FmtFprintfIntInt-16          263ns ± 2%     217ns ± 2%  -17.34%  (p=0.008 n=5+5)
FmtFprintfPrefixedInt-16     230ns ± 1%     212ns ± 1%   -7.99%  (p=0.008 n=5+5)
FmtFprintfFloat-16           411ns ± 3%     344ns ± 5%  -16.43%  (p=0.008 n=5+5)
FmtManyArgs-16               828ns ± 4%     790ns ± 2%   -4.59%  (p=0.032 n=5+5)
GobDecode-16                10.9ms ± 4%    10.8ms ± 5%     ~     (p=0.548 n=5+5)
GobEncode-16                9.52ms ± 5%    9.46ms ± 2%     ~     (p=1.000 n=5+5)
Gzip-16                      334ms ± 2%     337ms ± 2%     ~     (p=0.548 n=5+5)
Gunzip-16                   64.4ms ± 1%    65.0ms ± 1%   +1.00%  (p=0.008 n=5+5)
HTTPClientServer-16          156µs ± 3%     155µs ± 3%     ~     (p=0.690 n=5+5)
JSONEncode-16               21.0ms ± 1%    21.8ms ± 0%   +3.76%  (p=0.016 n=5+4)
JSONDecode-16               95.1ms ± 0%    95.7ms ± 1%     ~     (p=0.151 n=5+5)
Mandelbrot200-16            6.38ms ± 1%    6.42ms ± 1%     ~     (p=0.095 n=5+5)
GoParse-16                  5.47ms ± 2%    5.36ms ± 1%   -1.95%  (p=0.016 n=5+5)
RegexpMatchEasy0_32-16       111ns ± 1%     111ns ± 1%     ~     (p=0.635 n=5+4)
RegexpMatchEasy0_1K-16       408ns ± 1%     411ns ± 2%     ~     (p=0.087 n=5+5)
RegexpMatchEasy1_32-16       103ns ± 1%     104ns ± 1%     ~     (p=0.484 n=5+5)
RegexpMatchEasy1_1K-16       659ns ± 2%     652ns ± 1%     ~     (p=0.571 n=5+5)
RegexpMatchMedium_32-16      176ns ± 2%     174ns ± 1%     ~     (p=0.476 n=5+5)
RegexpMatchMedium_1K-16     58.6µs ± 4%    57.7µs ± 4%     ~     (p=0.548 n=5+5)
RegexpMatchHard_32-16       3.07µs ± 3%    3.04µs ± 4%     ~     (p=0.421 n=5+5)
RegexpMatchHard_1K-16       89.2µs ± 1%    87.9µs ± 2%   -1.52%  (p=0.032 n=5+5)
Revcomp-16                   575ms ± 0%     587ms ± 2%   +2.12%  (p=0.032 n=4+5)
Template-16                  110ms ± 1%     107ms ± 3%   -3.00%  (p=0.032 n=5+5)
TimeParse-16                 463ns ± 0%     462ns ± 0%     ~     (p=0.810 n=5+4)
TimeFormat-16                538ns ± 0%     535ns ± 0%   -0.63%  (p=0.024 n=5+5)

name                      old speed      new speed      delta
GobDecode-16              70.7MB/s ± 4%  71.4MB/s ± 5%     ~     (p=0.452 n=5+5)
GobEncode-16              80.7MB/s ± 5%  81.2MB/s ± 2%     ~     (p=1.000 n=5+5)
Gzip-16                   58.2MB/s ± 2%  57.7MB/s ± 2%     ~     (p=0.452 n=5+5)
Gunzip-16                  302MB/s ± 1%   299MB/s ± 1%   -0.99%  (p=0.008 n=5+5)
JSONEncode-16             92.4MB/s ± 1%  89.1MB/s ± 0%   -3.63%  (p=0.016 n=5+4)
JSONDecode-16             20.4MB/s ± 0%  20.3MB/s ± 1%     ~     (p=0.135 n=5+5)
GoParse-16                10.6MB/s ± 2%  10.8MB/s ± 1%   +2.00%  (p=0.016 n=5+5)
RegexpMatchEasy0_32-16     286MB/s ± 1%   285MB/s ± 3%     ~     (p=1.000 n=5+5)
RegexpMatchEasy0_1K-16    2.51GB/s ± 1%  2.49GB/s ± 2%     ~     (p=0.095 n=5+5)
RegexpMatchEasy1_32-16     309MB/s ± 1%   307MB/s ± 1%     ~     (p=0.548 n=5+5)
RegexpMatchEasy1_1K-16    1.55GB/s ± 2%  1.57GB/s ± 1%     ~     (p=0.690 n=5+5)
RegexpMatchMedium_32-16   5.68MB/s ± 2%  5.73MB/s ± 1%     ~     (p=0.579 n=5+5)
RegexpMatchMedium_1K-16   17.5MB/s ± 4%  17.8MB/s ± 4%     ~     (p=0.500 n=5+5)
RegexpMatchHard_32-16     10.4MB/s ± 3%  10.5MB/s ± 4%     ~     (p=0.460 n=5+5)
RegexpMatchHard_1K-16     11.5MB/s ± 1%  11.7MB/s ± 2%   +1.57%  (p=0.032 n=5+5)
Revcomp-16                 442MB/s ± 0%   433MB/s ± 2%   -2.05%  (p=0.032 n=4+5)
Template-16               17.7MB/s ± 1%  18.2MB/s ± 3%   +3.12%  (p=0.032 n=5+5)

Change-Id: I6972e8f35f2b31f9a42ac473a6bf419a18022558
Reviewed-on: https://go-review.googlesource.com/100935
Run-TryBot: Giovanni Bajo <rasky@develer.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2018-03-15 16:41:59 +00:00
Geoff Berry
e244a7a7d3 cmd/compile/internal/ssa: add patterns for arm64 bitfield opcodes
Add patterns to match common idioms for EXTR, BFI, BFXIL, SBFIZ, SBFX,
UBFIZ and UBFX opcodes.

go1 benchmarks results on Amberwing:
name                   old time/op    new time/op    delta
FmtManyArgs               786ns ± 2%     714ns ± 1%  -9.20%  (p=0.000 n=10+10)
Gzip                      437ms ± 0%     402ms ± 0%  -7.99%  (p=0.000 n=10+10)
FmtFprintfIntInt          196ns ± 0%     182ns ± 0%  -7.28%  (p=0.000 n=10+9)
FmtFprintfPrefixedInt     207ns ± 0%     199ns ± 0%  -3.86%  (p=0.000 n=10+10)
FmtFprintfFloat           324ns ± 0%     316ns ± 0%  -2.47%  (p=0.000 n=10+8)
FmtFprintfInt             119ns ± 0%     117ns ± 0%  -1.68%  (p=0.000 n=10+9)
GobDecode                12.8ms ± 2%    12.6ms ± 1%  -1.62%  (p=0.002 n=10+10)
JSONDecode               94.4ms ± 1%    93.4ms ± 0%  -1.10%  (p=0.000 n=10+10)
RegexpMatchEasy0_32       247ns ± 0%     245ns ± 0%  -0.65%  (p=0.000 n=10+10)
RegexpMatchMedium_32      314ns ± 0%     312ns ± 0%  -0.64%  (p=0.000 n=10+10)
RegexpMatchEasy0_1K       541ns ± 0%     538ns ± 0%  -0.55%  (p=0.000 n=10+9)
TimeParse                 450ns ± 1%     448ns ± 1%  -0.42%  (p=0.035 n=9+9)
RegexpMatchEasy1_32       244ns ± 0%     243ns ± 0%  -0.41%  (p=0.000 n=10+10)
GoParse                  6.03ms ± 0%    6.00ms ± 0%  -0.40%  (p=0.002 n=10+10)
RegexpMatchEasy1_1K       779ns ± 0%     777ns ± 0%  -0.26%  (p=0.000 n=10+10)
RegexpMatchHard_32       2.75µs ± 0%    2.74µs ± 1%  -0.06%  (p=0.026 n=9+9)
BinaryTree17              11.7s ± 0%     11.6s ± 0%    ~     (p=0.089 n=10+10)
HTTPClientServer         89.1µs ± 1%    89.5µs ± 2%    ~     (p=0.436 n=10+10)
RegexpMatchHard_1K       78.9µs ± 0%    79.5µs ± 2%    ~     (p=0.469 n=10+10)
FmtFprintfEmpty          58.5ns ± 0%    58.5ns ± 0%    ~     (all equal)
GobEncode                12.0ms ± 1%    12.1ms ± 0%    ~     (p=0.075 n=10+10)
Revcomp                   669ms ± 0%     668ms ± 0%    ~     (p=0.091 n=7+9)
Mandelbrot200            5.35ms ± 0%    5.36ms ± 0%  +0.07%  (p=0.000 n=9+9)
RegexpMatchMedium_1K     52.1µs ± 0%    52.1µs ± 0%  +0.10%  (p=0.000 n=9+9)
Fannkuch11                3.25s ± 0%     3.26s ± 0%  +0.36%  (p=0.000 n=9+10)
FmtFprintfString          114ns ± 1%     115ns ± 0%  +0.52%  (p=0.011 n=10+10)
JSONEncode               20.2ms ± 0%    20.3ms ± 0%  +0.65%  (p=0.000 n=10+10)
Template                 91.3ms ± 0%    92.3ms ± 0%  +1.08%  (p=0.000 n=10+10)
TimeFormat                484ns ± 0%     495ns ± 1%  +2.30%  (p=0.000 n=9+10)

There are some opportunities to improve this change further by adding
patterns to match the "extended register" versions of ADD/SUB/CMP, but I
think that should be evaluated on its own.  The regressions in Template
and TimeFormat would likely be recovered by this, as they seem to be due
to generating:

    ubfiz x0, x0, #3, #8
    add x1, x2, x0

instead of

    add x1, x2, x0, lsl #3

Change-Id: I5644a8d70ac7a98e784a377a2b76ab47a3415a4b
Reviewed-on: https://go-review.googlesource.com/88355
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2018-03-15 14:10:41 +00:00
Alberto Donizetti
ded9a1b372 test/codegen: port len/cap pow2 div tests to codegen
And delete them from asm_test.

Change-Id: I29c8d098a8893e6b669b6272a2f508985ac9d618
Reviewed-on: https://go-review.googlesource.com/100876
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2018-03-15 13:34:01 +00:00
Ilya Tocar
644d14ea0f Revert "cmd/compile: implement CMOV on amd64"
This reverts commit 080187f4f7.

It broke build of golang.org/x/exp/shiny/iconvg
See issue 24395 for details

Change-Id: Ifd6134f6214e6cee40bd3c63c32941d5fc96ae8b
Reviewed-on: https://go-review.googlesource.com/100755
Run-TryBot: Ilya Tocar <ilya.tocar@intel.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2018-03-14 21:21:23 +00:00
Alberto Donizetti
cd3aae9b81 test/codegen: port all small memmove tests to codegen
This change ports all the remaining tests checking that small memmoves
are replaced with MOVs to the new codegen test harness, and deletes
them from the asm_test file.

Change-Id: I01c94b441e27a5d61518035af62d62779dafeb56
Reviewed-on: https://go-review.googlesource.com/100476
Run-TryBot: Alberto Donizetti <alb.donizetti@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2018-03-14 15:57:07 +00:00
Alberto Donizetti
858042b8fd test/codegen: add codegen tests for div
Change-Id: I6ce8981e85fd55ade6078b0946e54a9215d9deca
Reviewed-on: https://go-review.googlesource.com/100575
Run-TryBot: Alberto Donizetti <alb.donizetti@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2018-03-14 15:56:46 +00:00
Tobias Klauser
d32018a500 test: check that size argument errors are emitted at call site
Add tests for the "negative size argument in make.*" and "size argument
too large in make.*" error messages to appear at call sites in case the
size is a const defined on another line.

As suggested by Matthew in a comment on CL 69910.

Change-Id: I5c33d4bec4e3d20bb21fe8019df27999997ddff3
Reviewed-on: https://go-review.googlesource.com/100395
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2018-03-14 08:36:15 +00:00
Matthew Dempsky
e601c07908 cmd/compile: reject type switch with guarded declaration and no cases
Fixes #23116.

Change-Id: I5db5c5c39bbb50148ffa18c9393b045f255f80a3
Reviewed-on: https://go-review.googlesource.com/100459
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
2018-03-13 22:02:46 +00:00
Robert Griesemer
363bcd7b4f cmd/compile: use key position for key:val elements in composite literals
Fixes #24339.

Change-Id: Ie47764fed27f76b480834b1fdbed0512c94831d9
Reviewed-on: https://go-review.googlesource.com/100457
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2018-03-13 21:44:12 +00:00
Matthew Dempsky
09d4455f45 cmd/compile: enable inlining variadic functions
As a side effect of working on mid-stack inlining, we've fixed support
for inlining variadic functions. Might as well enable it.

Change-Id: I7f555f8b941969791db7eb598c0b49f6dc0820aa
Reviewed-on: https://go-review.googlesource.com/100456
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-03-13 20:34:03 +00:00
Vladimir Kuzmin
7395083136 cmd/compile: avoid extra mapaccess in "m[k] op= r"
Currently, order desugars map assignment operations like

    m[k] op= r

into

    m[k] = m[k] op r

which in turn is transformed during walk into:

    tmp := *mapaccess(m, k)
    tmp = tmp op r
    *mapassign(m, k) = tmp

However, this is suboptimal, as we could instead produce just:

    *mapassign(m, k) op= r

One complication though is if "r == 0", then "m[k] /= r" and "m[k] %=
r" will panic, and they need to do so *before* calling mapassign,
otherwise we may insert a new zero-value element into the map.

It would be spec compliant to just emit the "r != 0" check before
calling mapassign (see #23735), but currently these checks aren't
generated until SSA construction. For now, it's simpler to continue
desugaring /= and %= into two map indexing operations.

Fixes #23661.

Change-Id: I46e3739d9adef10e92b46fdd78b88d5aabe68952
Reviewed-on: https://go-review.googlesource.com/91557
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
2018-03-12 19:27:44 +00:00
isharipo
85a8d25d53 cmd/compile/internal/ssa: emit IMUL3{L/Q} for MUL{L/Q}const on x86
cmd/asm now supports three-operand form of IMUL,
so instead of using IMUL with resultInArg0, emit IMUL3 instruction.

This results in less redundant MOVs where SSA assigns
different registers to input[0] and dst arguments.

Note: these have exactly the same encoding when reg0=reg1:
      IMUL3x $const, reg0, reg1
      IMULx $const, reg
Two-operand IMULx is like a crippled IMUL3x, with dst fixed to input[0].
This is why we don't bother to generate IMULx for the case where
dst is the same as input[0].

Change-Id: I4becda475b3dffdd07b6fdf1c75bacc82af654e4
Reviewed-on: https://go-review.googlesource.com/99656
Run-TryBot: Iskander Sharipov <iskander.sharipov@intel.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Giovanni Bajo <rasky@develer.com>
Reviewed-by: Keith Randall <khr@golang.org>
2018-03-12 19:02:36 +00:00
Giovanni Bajo
080187f4f7 cmd/compile: implement CMOV on amd64
This builds upon the branchelim pass, activating it for amd64 and
lowering CondSelect. Special care is made to FPU instructions for
NaN handling.

Benchmark results on Xeon E5630 (Westmere EP):

name                      old time/op    new time/op    delta
BinaryTree17-16              4.99s ± 9%     4.66s ± 2%     ~     (p=0.095 n=5+5)
Fannkuch11-16                4.93s ± 3%     5.04s ± 2%     ~     (p=0.548 n=5+5)
FmtFprintfEmpty-16          58.8ns ± 7%    61.4ns ±14%     ~     (p=0.579 n=5+5)
FmtFprintfString-16          114ns ± 2%     114ns ± 4%     ~     (p=0.603 n=5+5)
FmtFprintfInt-16             181ns ± 4%     125ns ± 3%  -30.90%  (p=0.008 n=5+5)
FmtFprintfIntInt-16          263ns ± 2%     217ns ± 2%  -17.34%  (p=0.008 n=5+5)
FmtFprintfPrefixedInt-16     230ns ± 1%     212ns ± 1%   -7.99%  (p=0.008 n=5+5)
FmtFprintfFloat-16           411ns ± 3%     344ns ± 5%  -16.43%  (p=0.008 n=5+5)
FmtManyArgs-16               828ns ± 4%     790ns ± 2%   -4.59%  (p=0.032 n=5+5)
GobDecode-16                10.9ms ± 4%    10.8ms ± 5%     ~     (p=0.548 n=5+5)
GobEncode-16                9.52ms ± 5%    9.46ms ± 2%     ~     (p=1.000 n=5+5)
Gzip-16                      334ms ± 2%     337ms ± 2%     ~     (p=0.548 n=5+5)
Gunzip-16                   64.4ms ± 1%    65.0ms ± 1%   +1.00%  (p=0.008 n=5+5)
HTTPClientServer-16          156µs ± 3%     155µs ± 3%     ~     (p=0.690 n=5+5)
JSONEncode-16               21.0ms ± 1%    21.8ms ± 0%   +3.76%  (p=0.016 n=5+4)
JSONDecode-16               95.1ms ± 0%    95.7ms ± 1%     ~     (p=0.151 n=5+5)
Mandelbrot200-16            6.38ms ± 1%    6.42ms ± 1%     ~     (p=0.095 n=5+5)
GoParse-16                  5.47ms ± 2%    5.36ms ± 1%   -1.95%  (p=0.016 n=5+5)
RegexpMatchEasy0_32-16       111ns ± 1%     111ns ± 1%     ~     (p=0.635 n=5+4)
RegexpMatchEasy0_1K-16       408ns ± 1%     411ns ± 2%     ~     (p=0.087 n=5+5)
RegexpMatchEasy1_32-16       103ns ± 1%     104ns ± 1%     ~     (p=0.484 n=5+5)
RegexpMatchEasy1_1K-16       659ns ± 2%     652ns ± 1%     ~     (p=0.571 n=5+5)
RegexpMatchMedium_32-16      176ns ± 2%     174ns ± 1%     ~     (p=0.476 n=5+5)
RegexpMatchMedium_1K-16     58.6µs ± 4%    57.7µs ± 4%     ~     (p=0.548 n=5+5)
RegexpMatchHard_32-16       3.07µs ± 3%    3.04µs ± 4%     ~     (p=0.421 n=5+5)
RegexpMatchHard_1K-16       89.2µs ± 1%    87.9µs ± 2%   -1.52%  (p=0.032 n=5+5)
Revcomp-16                   575ms ± 0%     587ms ± 2%   +2.12%  (p=0.032 n=4+5)
Template-16                  110ms ± 1%     107ms ± 3%   -3.00%  (p=0.032 n=5+5)
TimeParse-16                 463ns ± 0%     462ns ± 0%     ~     (p=0.810 n=5+4)
TimeFormat-16                538ns ± 0%     535ns ± 0%   -0.63%  (p=0.024 n=5+5)

name                      old speed      new speed      delta
GobDecode-16              70.7MB/s ± 4%  71.4MB/s ± 5%     ~     (p=0.452 n=5+5)
GobEncode-16              80.7MB/s ± 5%  81.2MB/s ± 2%     ~     (p=1.000 n=5+5)
Gzip-16                   58.2MB/s ± 2%  57.7MB/s ± 2%     ~     (p=0.452 n=5+5)
Gunzip-16                  302MB/s ± 1%   299MB/s ± 1%   -0.99%  (p=0.008 n=5+5)
JSONEncode-16             92.4MB/s ± 1%  89.1MB/s ± 0%   -3.63%  (p=0.016 n=5+4)
JSONDecode-16             20.4MB/s ± 0%  20.3MB/s ± 1%     ~     (p=0.135 n=5+5)
GoParse-16                10.6MB/s ± 2%  10.8MB/s ± 1%   +2.00%  (p=0.016 n=5+5)
RegexpMatchEasy0_32-16     286MB/s ± 1%   285MB/s ± 3%     ~     (p=1.000 n=5+5)
RegexpMatchEasy0_1K-16    2.51GB/s ± 1%  2.49GB/s ± 2%     ~     (p=0.095 n=5+5)
RegexpMatchEasy1_32-16     309MB/s ± 1%   307MB/s ± 1%     ~     (p=0.548 n=5+5)
RegexpMatchEasy1_1K-16    1.55GB/s ± 2%  1.57GB/s ± 1%     ~     (p=0.690 n=5+5)
RegexpMatchMedium_32-16   5.68MB/s ± 2%  5.73MB/s ± 1%     ~     (p=0.579 n=5+5)
RegexpMatchMedium_1K-16   17.5MB/s ± 4%  17.8MB/s ± 4%     ~     (p=0.500 n=5+5)
RegexpMatchHard_32-16     10.4MB/s ± 3%  10.5MB/s ± 4%     ~     (p=0.460 n=5+5)
RegexpMatchHard_1K-16     11.5MB/s ± 1%  11.7MB/s ± 2%   +1.57%  (p=0.032 n=5+5)
Revcomp-16                 442MB/s ± 0%   433MB/s ± 2%   -2.05%  (p=0.032 n=4+5)
Template-16               17.7MB/s ± 1%  18.2MB/s ± 3%   +3.12%  (p=0.032 n=5+5)

Change-Id: Ic7cb7374d07da031e771bdcbfdd832fd1b17159c
Reviewed-on: https://go-review.googlesource.com/98695
Reviewed-by: Ilya Tocar <ilya.tocar@intel.com>
2018-03-12 18:01:33 +00:00
Giovanni Bajo
f7ac70a566 test: move rotate tests to top-level testsuite.
Remove old tests from asm_test.

Change-Id: Ib408ec7faa60068bddecf709b93ce308e0ef665a
Reviewed-on: https://go-review.googlesource.com/100075
Reviewed-by: Alberto Donizetti <alb.donizetti@gmail.com>
2018-03-11 10:08:18 +00:00
Alberto Donizetti
8e427a3878 test/codegen: add README file for the codegen test harness
This change adds a README file inside the test/codegen directory,
explaining how to run the codegen tests and the syntax of the regexps
comments used to match assembly instructions.

Change-Id: Ica4eb3ffa9c6975371538cc8ae0ac3c1a3a03baf
Reviewed-on: https://go-review.googlesource.com/99156
Reviewed-by: Keith Randall <khr@golang.org>
2018-03-09 18:38:53 +00:00
Alberto Donizetti
5f541b11aa test/codegen: port MULs merging tests to codegen
And delete them from asm_go.

Change-Id: I0057cbd90ca55fa51c596e32406e190f3866f93e
Reviewed-on: https://go-review.googlesource.com/99815
Reviewed-by: Keith Randall <khr@golang.org>
2018-03-09 17:01:56 +00:00
Alberto Donizetti
cde34780b7 test/codegen: port math/bits.RotateLeft tests to codegen
Only RotateLeft{64,32} were tested, and just for ppc64. This CL adds
tests for RotateLeft{64,32,16,8} on arm64 and amd64/386, for the cases
where the calls are actually instrinsified.

RotateLeft tests (the last ones for math/bits functions) are deleted
from asm_test.

This CL also adds a space between the "//" and the arch name in the
comments, to uniform this file to the style used in all the other
files.

Change-Id: Ifc2a27261d70bcc294b4ec64490d8367f62d2b89
Reviewed-on: https://go-review.googlesource.com/99596
Reviewed-by: Giovanni Bajo <rasky@develer.com>
2018-03-09 10:53:38 +00:00
Austin Clements
6436270dad cmd/compile: add fence-post implications to prove
This adds four new deductions to the prove pass, all related to adding
or subtracting one from a value. This is the first hint of actual
arithmetic relations in the prove pass.

The most effective of these is

   x-1 >= w && x > min  ⇒  x > w

This helps eliminate bounds checks in code like

  if x > 0 {
    // do something with s[x-1]
  }

Altogether, these deductions prove an additional 260 branches in std
and cmd. Furthermore, they will let us eliminate some tricky
compiler-inserted panics in the runtime that are interfering with
static analysis.

Fixes #23354.

Change-Id: I7088223e0e0cd6ff062a75c127eb4bb60e6dce02
Reviewed-on: https://go-review.googlesource.com/87480
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Alexandru Moșoi <alexandru@mosoi.ro>
2018-03-08 22:25:28 +00:00
Austin Clements
941fc129e2 cmd/compile: derive unsigned limits from signed limits in prove
This adds a few simple deductions to the prove pass' fact table to
derive unsigned concrete limits from signed concrete limits where
possible.

This tweak lets the pass prove 70 additional branch conditions in std
and cmd.

This is based on a comment from the recently-deleted factsTable.get:
"// TODO: also use signed data if lim.min >= 0".

Change-Id: Ib4340249e7733070f004a0aa31254adf5df8a392
Reviewed-on: https://go-review.googlesource.com/87479
Reviewed-by: Alexandru Moșoi <alexandru@mosoi.ro>
Reviewed-by: Keith Randall <khr@golang.org>
2018-03-08 22:25:27 +00:00
Austin Clements
669db2cef5 cmd/compile: make prove pass use unsatisfiability
Currently the prove pass uses implication queries. For each block, it
collects the set of branch conditions leading to that block, and
queries this fact table for whether any of these facts imply the
block's own branch condition (or its inverse). This works remarkably
well considering it doesn't do any deduction on these facts, but it
has various downsides:

1. It requires an implementation both of adding facts to the table and
   determining implications. These are very nearly duals of each
   other, but require separate implementations. Likewise, the process
   of asserting facts of dominating branch conditions is very nearly
   the dual of the process of querying implied branch conditions.

2. It leads to less effective use of derived facts. For example, the
   prove pass currently derives facts about the relations between len
   and cap, but can't make use of these unless a branch condition is
   in the exact form of a derived fact. If one of these derived facts
   contradicts another fact, it won't notice or make use of this.

This CL changes the approach of the prove pass to instead use
*contradiction* instead of implication. Rather than ever querying a
branch condition, it simply adds branch conditions to the fact table.
If this leads to a contradiction (specifically, it makes the fact set
unsatisfiable), that branch is impossible and can be cut. As a result,

1. We can eliminate the code for determining implications
   (factsTable.get disappears entirely). Also, there is now a single
   implementation of visiting and asserting branch conditions, since
   we don't have to flip them around to treat them as facts in one
   place and queries in another.

2. Derived facts can be used effectively. It doesn't matter *why* the
   fact table is unsatisfiable; a contradiction in any of the facts is
   enough.

3. As an added benefit, it's now quite easy to avoid traversing beyond
   provably-unreachable blocks. In contrast, the current
   implementation always visits all blocks.

The prove pass already has nearly all of the mechanism necessary to
compute unsatisfiability, which means this both simplifies the code
and makes it more powerful.

The only complication is that the current implication procedure has a
hack for dealing with the 0 <= Args[0] condition of OpIsInBounds and
OpIsSliceInBounds. We replace this with asserting the appropriate fact
when we process one of these conditions. This seems much cleaner
anyway, and works because we can now take advantage of derived facts.

This has no measurable effect on compiler performance.

Effectiveness:

There is exactly one condition in all of std and cmd that this fails
to prove that the old implementation could: (int64(^uint(0)>>1) < x)
in encoding/gob. This can never be true because x is an int, and it's
basically coincidence that the old code gets this. (For example, it
fails to prove the similar (x < ^int64(^uint(0)>>1)) condition that
immediately precedes it, and even though the conditions are logically
unrelated, it wouldn't get the second one if it hadn't first processed
the first!)

It does, however, prove a few dozen additional branches. These come
from facts that are added to the fact table about the relations
between len and cap. These were almost never queried directly before,
but could lead to contradictions, which the unsat-based approach is
able to use.

There are exactly two branches in std and cmd that this implementation
proves in the *other* direction. This sounds scary, but is okay
because both occur in already-unreachable blocks, so it doesn't matter
what we chose. Because the fact table logic is sound but incomplete,
it fails to prove that the block isn't reachable, even though it is
able to prove that both outgoing branches are impossible. We could
turn these blocks into BlockExit blocks, but it doesn't seem worth the
trouble of the extra proof effort for something that happens twice in
all of std and cmd.

Tests:

This CL updates test/prove.go to change the expected messages because
it can no longer give a "reason" why it proved or disproved a
condition. It also adds a new test of a branch it couldn't prove
before.

It mostly guts test/sliceopt.go, removing everything related to slice
bounds optimizations and moving a few relevant tests to test/prove.go.
Much of this test is actually unreachable. The new prove pass figures
this out and doesn't try to prove anything about the unreachable
parts. The output on the unreachable parts is already suspect because
anything can be proved at that point, so it's really just a regression
test for an algorithm the compiler no longer uses.

This is a step toward fixing #23354. That issue is quite easy to fix
once we can use derived facts effectively.

Change-Id: Ia48a1b9ee081310579fe474e4a61857424ff8ce8
Reviewed-on: https://go-review.googlesource.com/87478
Reviewed-by: Keith Randall <khr@golang.org>
2018-03-08 22:25:25 +00:00
Alberto Donizetti
3772b2e1d5 test/codegen: port 2^n muls tests to codegen harness
And delete them from the asm_test.go file.

Change-Id: I124c8c352299646ec7db0968cdb0fe59a3b5d83d
Reviewed-on: https://go-review.googlesource.com/99475
Run-TryBot: Alberto Donizetti <alb.donizetti@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Giovanni Bajo <rasky@develer.com>
2018-03-08 16:30:14 +00:00
Matthew Dempsky
88466e93a4 cmd/compile: mark anonymous receiver parameters as non-escaping
This was already done for normal parameters, and the same logic
applies for receiver parameters too.

Updates #24305.

Change-Id: Ia2a46f68d14e8fb62004ff0da1db0f065a95a1b7
Reviewed-on: https://go-review.googlesource.com/99335
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-03-08 00:20:01 +00:00
Alberto Donizetti
c028958393 test/codegen: fix issue with arm64 memmove codegen test
This recently added arm64 memmove codegen check:

  func movesmall() {
    // arm64:-"memmove"
    x := [...]byte{1, 2, 3, 4, 5, 6, 7}
    copy(x[1:], x[:])
  }

is not correct, for two reasons:

1. regexps are matched from the start of the disasm line (excluding
   line information). This mean that a negative -"memmove" check will
   pass against a 'CALL runtime.memmove' line because the line does
   not start with 'memmove' (its starts with CALL...).
   The way to specify no 'memmove' match whatsoever on the line is
   -".*memmove"

2. AFAIK comments on their own line are matched against the first
   subsequent non-comment line. So the code above only verifies that
   the x := ... line does not generate a memmove. The comment should
   be moved near the copy() line, if it's that one we want to not
   generate a memmove call.

The fact that the test above is not effective can be checked by
running `go run run.go -v codegen` in the toplevel test directory with
a go1.10 toolchain (that does not have the memmove-elision
optimization). The test will still pass (it shouldn't).

This change changes the regexp to -".*memmove" and moves it near the
line it needs to (not)match.

Change-Id: Ie01ef4d775e77d92dc8d8b7856b89b200f5e5ef2
Reviewed-on: https://go-review.googlesource.com/98977
Run-TryBot: Alberto Donizetti <alb.donizetti@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2018-03-07 16:41:24 +00:00
Kunpei Sakai
b75e8a2a3b cmd/compile: prevent detection of wrong duplicates
by including *types.Type in typeVal.

Updates #21866
Fixes #24159

Change-Id: I2f8cac252d88d43e723124f2867b1410b7abab7b
Reviewed-on: https://go-review.googlesource.com/98476
Run-TryBot: Kunpei Sakai <namusyaka@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2018-03-07 01:26:00 +00:00
ChrisALiles
42ecf39e85 cmd/compile: improve compiler error on embedded structs
Fixes #23609

Change-Id: I751aae3d849de7fce1306324fcb1a4c3842d873e
Reviewed-on: https://go-review.googlesource.com/97076
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2018-03-06 21:06:46 +00:00
Alberto Donizetti
8516ecd05f test/codegen: port math/bits.ReverseBytes tests to codegen
And remove them from ssa_test.

Change-Id: If767af662801219774d1bdb787c77edfa6067770
Reviewed-on: https://go-review.googlesource.com/98976
Run-TryBot: Alberto Donizetti <alb.donizetti@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Giovanni Bajo <rasky@develer.com>
2018-03-06 20:34:33 +00:00
Wei Xiao
05962561ae cmd/compile/internal/ssa: improve store combine optimization on arm64
Current implementation doesn't consider MOVDreg type operand and fail to combine
it into larger store. This patch fixes the issue.

Fixes #24242

Change-Id: I7d68697f80e76f48c3528ece01a602bf513248ec
Reviewed-on: https://go-review.googlesource.com/98397
Run-TryBot: Giovanni Bajo <rasky@develer.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2018-03-06 20:29:04 +00:00
Balaram Makam
0e8b7110f6 cmd/compile/internal/ssa: inline small memmove for arm64
This patch enables the optimization for arm64 target.

Performance results on Amberwing for strconv benchmark:
name             old time/op  new time/op  delta
Quote             721ns ± 0%   617ns ± 0%  -14.40%  (p=0.016 n=5+4)
QuoteRune         118ns ± 0%   117ns ± 0%   -0.85%  (p=0.008 n=5+5)
AppendQuote       436ns ± 2%   321ns ± 0%  -26.31%  (p=0.008 n=5+5)
AppendQuoteRune  34.7ns ± 0%  28.4ns ± 0%  -18.16%  (p=0.000 n=5+4)
[Geo mean]        189ns        160ns       -15.41%

Change-Id: I5714c474e7483d07ca338fbaf49beb4bbcc11c44
Reviewed-on: https://go-review.googlesource.com/98735
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Giovanni Bajo <rasky@develer.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2018-03-06 18:37:19 +00:00
Alberto Donizetti
18ae5eca3b test/codegen: port math/bits.OnesCount tests to codegen
And remove them from ssa_test.

Change-Id: I3efac5fea529bb0efa2dae32124530482ba5058e
Reviewed-on: https://go-review.googlesource.com/98815
Reviewed-by: Keith Randall <khr@golang.org>
2018-03-06 17:53:00 +00:00
Alberto Donizetti
85dcc709a8 test/codegen: port math/bits.TrailingZeros tests to codegen
And remove them from ssa_test.

Change-Id: Ib5de5c0d908f23915e0847eca338cacf2fa5325b
Reviewed-on: https://go-review.googlesource.com/98795
Reviewed-by: Giovanni Bajo <rasky@develer.com>
2018-03-06 11:48:37 +00:00
Alberto Donizetti
83e41b3e76 test/codegen: port math/bits.Leadingzero tests to codegen
Change-Id: Ic21d25db5d56ce77516c53082dfbc010e5875b81
Reviewed-on: https://go-review.googlesource.com/98655
Run-TryBot: Alberto Donizetti <alb.donizetti@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2018-03-05 19:52:04 +00:00
Alberto Donizetti
c1806906d8 test: port bits.Len intrinsics tests to the new codegen harness
This change move bits.Len* intrinsification tests to the new codegen
test harness, removing them from the old ssa_test file. Five different
test functions (one for each bit.Len function tested) was used, to
avoid possible unwanted interactions between multiple calls inside one
function.

Change-Id: Iffd5be55b58e88597fa30a562a28dacb01236d8b
Reviewed-on: https://go-review.googlesource.com/98156
Run-TryBot: Alberto Donizetti <alb.donizetti@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Giovanni Bajo <rasky@develer.com>
2018-03-05 18:01:19 +00:00
Giovanni Bajo
89ae7045f3 test: convert all math-related tests from asm_test
Change-Id: If542f0b5c5754e6eb2f9b302fe5a148ba9a57338
Reviewed-on: https://go-review.googlesource.com/98443
Run-TryBot: Giovanni Bajo <rasky@develer.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2018-03-04 16:52:33 +00:00
Giovanni Bajo
fad31e513d test: move load/store combines into asmcheck
This CL moves the load/store combining tests into asmcheck.
In addition at being more compact, it's also now easier to
spot what it is missing in each architecture.

While doing so, I think I uncovered a bug in ppc64le and arm64
rules, because they fail to load/store combine in non-trivial
functions. Not sure why, I'll open an issue.

Change-Id: Ia1572d53c0553d9104f3e52b95e4d1768a8440a3
Reviewed-on: https://go-review.googlesource.com/98441
Run-TryBot: Giovanni Bajo <rasky@develer.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2018-03-04 16:52:03 +00:00
Giovanni Bajo
80bfb75c42 test: in asmcheck, dump only the functions which fail
Before this change, in case of any failure, asmcheck was
dumping to stderr the whole output of compile -S, which
can be very long if it contains multiple functions.

Make it so it filters the output to only display the
assembly output of functions for which at least one opcode
check failed. This greatly simplifies debugging.

Change-Id: I1bbf54473b8252a3384e2c1dade82d926afc119d
Reviewed-on: https://go-review.googlesource.com/98444
Run-TryBot: Giovanni Bajo <rasky@develer.com>
Reviewed-by: Keith Randall <khr@golang.org>
2018-03-04 01:05:02 +00:00
Giovanni Bajo
8ce74b7d11 test: port a nil-check interface test from asm_test
Change-Id: I69c1688506d1aeca655047acf35d1bff966fc01e
Reviewed-on: https://go-review.googlesource.com/98442
Run-TryBot: Giovanni Bajo <rasky@develer.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2018-03-03 20:20:54 +00:00
Giovanni Bajo
ec0b8c0585 test: use the version of Go used to run run.go
Currently, the top-level testsuite always uses whatever version
of Go is found in the PATH to execute all the tests. This
forces the developers to tweak the PATH to run the testsuite.

Change it to use the same version of Go used to run run.go.
This allows developers to run the testsuite using the tip
compiler by simply saying "../bin/go run run.go".

I think this is a better solution compared to always forcing
"../bin/go", because it allows developers to run the testsuite
using different Go versions, for instance to check if a new
test is fixed in tip compared to the installed compiler.

Fixes #24217

Change-Id: I41b299c753b6e77c41e28be9091b2b630efea9d2
Reviewed-on: https://go-review.googlesource.com/98439
Run-TryBot: Giovanni Bajo <rasky@develer.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2018-03-03 19:52:00 +00:00
Alberto Donizetti
644b2dafc2 test/codegen: add copyright headers to new codegen files
Change-Id: I9fe6572d1043ef9ee09c0925059ded554ad24c6b
Reviewed-on: https://go-review.googlesource.com/98215
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-03-02 20:13:13 +00:00
Cherry Zhang
2baed3856d cmd/asm: fix assembling return jump
In RET instruction, the operand is the return jump's target,
which should be put in Prog.To.

Add an action "buildrundir" to the test driver, which builds
(compile+assemble+link) the code in a directory and runs the
resulting binary.

Fixes #23838.

Change-Id: I7ebe7eda49024b40a69a24857322c5ca9c67babb
Reviewed-on: https://go-review.googlesource.com/94175
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
2018-03-01 21:11:16 +00:00
Giovanni Bajo
f16cc298d3 test: implement negative rules in asmcheck
Change-Id: I2b507e35cc314100eaf2ec2d1e5107cc2fc9e7cf
Reviewed-on: https://go-review.googlesource.com/97818
Reviewed-by: Keith Randall <khr@golang.org>
2018-03-01 18:15:24 +00:00
Giovanni Bajo
0bcf8bcd99 test: in asmcheck, regexp must match from beginning of line
This avoid simple bugs like "ADD" matching "FADD". Obviously
"ADD" will still match "ADDQ" so some care is still required
in this regard, but at least a first class of possible errors
is taken care of.

Change-Id: I7deb04c31de30bedac9c026d9889ace4a1d2adcb
Reviewed-on: https://go-review.googlesource.com/97817
Reviewed-by: Giovanni Bajo <rasky@develer.com>
Reviewed-by: Keith Randall <khr@golang.org>
2018-03-01 18:14:54 +00:00
Giovanni Bajo
879a1ff1e4 test: improve asmcheck syntax
asmcheck comments now support a compact form of specifying
multiple checks for each platform, using the following syntax:

   amd64:"SHL\t[$]4","SHR\t[$]4"

Negative checks are also parsed using the following syntax:

   amd64:-"ROR"

though they are still not working.

Moreover, out-of-line comments have been implemented. This
allows to specify asmchecks on comment-only lines, that will
be matched on the first subsequent non-comment non-empty line.

    // amd64:"XOR"
    // arm:"EOR"

    x ^= 1

Change-Id: I110c7462fc6a5c70fd4af0d42f516016ae7f2760
Reviewed-on: https://go-review.googlesource.com/97816
Reviewed-by: Keith Randall <khr@golang.org>
2018-03-01 18:10:48 +00:00
Josh Bleecher Snyder
aa9c1a8f80 runtime: fix amd64p32 indexbytes in presence of overflow
When the slice/string length is very large,
probably artifically large as in CL 97523,
adding BX (length) to R11 (pointer) overflows.
As a result, checking DI < R11 yields the wrong result.
Since they will be equal when the loop is done,
just check DI != R11 instead.
Yes, the pointer itself could overflow, but if that happens,
something else has gone pretty wrong; not our concern here.

Fixes #24187

Change-Id: I2f60fc6ccae739345d01bc80528560726ad4f8c6
Reviewed-on: https://go-review.googlesource.com/97802
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2018-03-01 16:53:33 +00:00
Giovanni Bajo
c9438cb198 test: add support for code generation tests (asmcheck)
The top-level test harness is modified to support a new kind
of test: "asmcheck". This is meant to replace asm_test.go
as an easier and more readable way to test code generation.

I've added a couple of codegen tests to get initial feedback
on the syntax. I've created them under a common "codegen"
subdirectory, so that it's easier to run them all with
"go run run.go -v codegen".

The asmcheck syntax allows to insert line comments that
can specify a regular expression to match in the assembly code,
for multiple architectures (the testsuite will automatically
build each testfile multiple times, one per mentioned architecture).

Negative matches are unsupported for now, so this cannot fully
replace asm_test yet.

Change-Id: Ifdbba389f01d55e63e73c99e5f5449e642101d55
Reviewed-on: https://go-review.googlesource.com/97355
Run-TryBot: Giovanni Bajo <rasky@develer.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Alberto Donizetti <alb.donizetti@gmail.com>
2018-03-01 07:59:54 +00:00
Matthew Dempsky
b3f00c6985 cmd/compile: fix unexpected type alias crash
OCOMPLIT stores the pre-typechecked type in n.Right, and then moves it
to n.Type. However, it wasn't clearing n.Right, so n.Right continued
to point to the OTYPE node. (Exception: slice literals reused n.Right
to store the array length.)

When exporting inline function bodies, we don't expect to need to save
any type aliases. Doing so wouldn't be wrong per se, but it's
completely unnecessary and would just bloat the export data.

However, reexportdep (whose role is to identify types needed by inline
function bodies) uses a generic tree traversal mechanism, which visits
n.Right even for O{ARRAY,MAP,STRUCT}LIT nodes. This means it finds the
OTYPE node, and mistakenly interpreted that the type alias needs to be
exported.

The straight forward fix is to just clear n.Right when typechecking
composite literals.

Fixes #24173.

Change-Id: Ia2d556bfdd806c83695b08e18b6cd71eff0772fc
Reviewed-on: https://go-review.googlesource.com/97719
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Robert Griesemer <gri@golang.org>
2018-02-28 20:18:37 +00:00
Daniel Martí
1e308fbc1a cmd/compile: improved error message when calling a shadowed builtin
Otherwise, the error can be confusing if one forgets or doesn't know
that the builtin is being shadowed, which is not common practice.

Fixes #22822.

Change-Id: I735393b5ce28cb83815a1c3f7cd2e7bb5080a32d
Reviewed-on: https://go-review.googlesource.com/97455
Reviewed-by: Robert Griesemer <gri@golang.org>
2018-02-28 19:39:52 +00:00
Robert Griesemer
0c884d0810 cmd/compile, cmd/compile/internal/syntax: print relative column info
This change enables printing of relative column information if a
prior line directive specified a valid column. If there was no
line directive, or the line directive didn't specify a column
(or the -C flag is specified), no column information is shown in
file positions.

Implementation: Column values (and line values, for that matter)
that are zero are interpreted as "unknown". A line directive that
doesn't specify a column records that as a zero column in the
respective PosBase data structure. When computing relative columns,
a relative value is zero of the base's column value is zero.
When formatting a position, a zero column value is not printed.

To make this work without special cases, the PosBase for a file
is given a concrete (non-0:0) position 1:1 with the PosBase's
line and column also being 1:1. In other words, at the position
1:1 of a file, it's relative positions are starting with 1:1 as
one would expect.

In the package syntax, this requires self-recursive PosBases for
file bases, matching what cmd/internal/src.PosBase was already
doing. In src.PosBase, file and inlining bases also need to be
based at 1:1 to indicate "known" positions.

This change completes the cmd/compiler part of the issue below.

Fixes #22662.

Change-Id: I6c3d2dee26709581fba0d0261b1d12e93f1cba1a
Reviewed-on: https://go-review.googlesource.com/97375
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2018-02-28 03:51:23 +00:00
Keith Randall
2413b54888 cmd/compile: mark the first word of an interface as a uintptr
The first word of an interface is a pointer, but for the purposes
of GC we don't need to treat it as such.
 1. If it is a non-empty interface, the pointer points to an itab
    which is always in persistentalloc space.
 2. If it is an empty interface, the pointer points to a _type.
   a. If it is a compile-time-allocated type, it points into
      the read-only data section.
   b. If it is a reflect-allocated type, it points into the Go heap.
      Reflect is responsible for keeping a reference to
      the underlying type so it won't be GCd.

If we ever have a moving GC, we need to change this for 2b (as
well as scan itabs to update their itab._type fields).

Write barriers on the first word of interfaces have already been removed.

Change-Id: I643e91d7ac4de980ac2717436eff94097c65d959
Reviewed-on: https://go-review.googlesource.com/97518
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
2018-02-27 22:58:32 +00:00
Matthew Dempsky
d7cd61ceaa cmd/compile: fix inlining of constant if statements
We accidentally overlooked needing to still visit Ninit for OIF
statements with constant conditions in golang.org/cl/96778.

Fixes #24120.

Change-Id: I5b341913065ff90e1163fb872b9e8d47e2a789d2
Reviewed-on: https://go-review.googlesource.com/97475
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2018-02-27 19:27:32 +00:00
Robert Griesemer
515fa58ac9 cmd/compile: track line directives w/ column information
Extend cmd/internal/src.PosBase to track column information,
and adjust the meaning of the PosBase position to mean the
position at which the PosBase's relative (line, col) position
starts (rather than indicating the position of the //line
directive). Because this semantic change is made in the
compiler's noder, it doesn't affect the logic of src.PosBase,
only its test setup (where PosBases are constructed with
corrected incomming positions). In short, src.PosBase now
matches syntax.PosBase with respect to the semantics of
src.PosBase.pos.

For #22662.

Change-Id: I5b1451cb88fff3f149920c2eec08b6167955ce27
Reviewed-on: https://go-review.googlesource.com/96535
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2018-02-26 18:32:03 +00:00
Ian Lance Taylor
9fba50545d test: add test case where gccgo incorrectly rejected aliases
Updates #23912

Change-Id: I50d06506a8ac91ed99a761a9ff3fd0b03d4c8121
Reviewed-on: https://go-review.googlesource.com/94995
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-02-20 01:57:14 +00:00
Keith Randall
4313d7767d cmd/compile: reset branch prediction when deleting a branch
When we go from a branch block to a plain block, reset the
branch prediction bit. Downstream passes asssume that if the
branch prediction is set, then the block has 2 successors.

Fixes #23504

Change-Id: I2898ec002228b2e34fe80ce420c6939201c0a5aa
Reviewed-on: https://go-review.googlesource.com/88955
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
2018-02-20 00:56:13 +00:00
Austin Clements
2b415549b8 runtime: use sparse mappings for the heap
This replaces the contiguous heap arena mapping with a potentially
sparse mapping that can support heap mappings anywhere in the address
space.

This has several advantages over the current approach:

* There is no longer any limit on the size of the Go heap. (Currently
  it's limited to 512GB.) Hence, this fixes #10460.

* It eliminates many failures modes of heap initialization and
  growing. In particular it eliminates any possibility of panicking
  with an address space conflict. This can happen for many reasons and
  even causes a low but steady rate of TSAN test failures because of
  conflicts with the TSAN runtime. See #16936 and #11993.

* It eliminates the notion of "non-reserved" heap, which was added
  because creating huge address space reservations (particularly on
  64-bit) led to huge process VSIZE. This was at best confusing and at
  worst conflicted badly with ulimit -v. However, the non-reserved
  heap logic is complicated, can race with other mappings in non-pure
  Go binaries (e.g., #18976), and requires that the entire heap be
  either reserved or non-reserved. We currently maintain the latter
  property, but it's quite difficult to convince yourself of that, and
  hence difficult to keep correct. This logic is still present, but
  will be removed in the next CL.

* It fixes problems on 32-bit where skipping over parts of the address
  space leads to mapping huge (and never-to-be-used) metadata
  structures. See #19831.

This also completely rewrites and significantly simplifies
mheap.sysAlloc, which has been a source of many bugs. E.g., #21044,
 #20259, #18651, and #13143 (and maybe #23222).

This change also makes it possible to allocate individual objects
larger than 512GB. As a result, a few tests that expected huge
allocations to fail needed to be changed to make even larger
allocations. However, at the moment attempting to allocate a humongous
object may cause the program to freeze for several minutes on Linux as
we fall back to probing every page with addrspace_free. That logic
(and this failure mode) will be removed in the next CL.

Fixes #10460.
Fixes #22204 (since it rewrites the code involved).

This slightly slows down compilebench and the x/benchmarks garbage
benchmark.

name       old time/op     new time/op     delta
Template       184ms ± 1%      185ms ± 1%    ~     (p=0.065 n=10+9)
Unicode       86.9ms ± 3%     86.3ms ± 1%    ~     (p=0.631 n=10+10)
GoTypes        599ms ± 0%      602ms ± 0%  +0.56%  (p=0.000 n=10+9)
Compiler       2.87s ± 1%      2.89s ± 1%  +0.51%  (p=0.002 n=9+10)
SSA            7.29s ± 1%      7.25s ± 1%    ~     (p=0.182 n=10+9)
Flate          118ms ± 2%      118ms ± 1%    ~     (p=0.113 n=9+9)
GoParser       147ms ± 1%      148ms ± 1%  +1.07%  (p=0.003 n=9+10)
Reflect        401ms ± 1%      404ms ± 1%  +0.71%  (p=0.003 n=10+9)
Tar            175ms ± 1%      175ms ± 1%    ~     (p=0.604 n=9+10)
XML            209ms ± 1%      210ms ± 1%    ~     (p=0.052 n=10+10)

(https://perf.golang.org/search?q=upload:20171231.4)

name                       old time/op  new time/op  delta
Garbage/benchmem-MB=64-12  2.23ms ± 1%  2.25ms ± 1%  +0.84%  (p=0.000 n=19+19)

(https://perf.golang.org/search?q=upload:20171231.3)

Relative to the start of the sparse heap changes (starting at and
including "runtime: fix various contiguous bitmap assumptions"),
overall slowdown is roughly 1% on GC-intensive benchmarks:

name        old time/op     new time/op     delta
Template        183ms ± 1%      185ms ± 1%  +1.32%  (p=0.000 n=9+9)
Unicode        84.9ms ± 2%     86.3ms ± 1%  +1.65%  (p=0.000 n=9+10)
GoTypes         595ms ± 1%      602ms ± 0%  +1.19%  (p=0.000 n=9+9)
Compiler        2.86s ± 0%      2.89s ± 1%  +0.91%  (p=0.000 n=9+10)
SSA             7.19s ± 0%      7.25s ± 1%  +0.75%  (p=0.000 n=8+9)
Flate           117ms ± 1%      118ms ± 1%  +1.10%  (p=0.000 n=10+9)
GoParser        146ms ± 2%      148ms ± 1%  +1.48%  (p=0.002 n=10+10)
Reflect         398ms ± 1%      404ms ± 1%  +1.51%  (p=0.000 n=10+9)
Tar             173ms ± 1%      175ms ± 1%  +1.17%  (p=0.000 n=10+10)
XML             208ms ± 1%      210ms ± 1%  +0.62%  (p=0.011 n=10+10)
[Geo mean]      369ms           373ms       +1.17%

(https://perf.golang.org/search?q=upload:20180101.2)

name                       old time/op  new time/op  delta
Garbage/benchmem-MB=64-12  2.22ms ± 1%  2.25ms ± 1%  +1.51%  (p=0.000 n=20+19)

(https://perf.golang.org/search?q=upload:20180101.3)

Change-Id: I5daf4cfec24b252e5a57001f0a6c03f22479d0f0
Reviewed-on: https://go-review.googlesource.com/85887
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Rick Hudson <rlh@golang.org>
2018-02-15 21:12:23 +00:00
Robert Griesemer
33eb0633e1 cmd/compile/internal/syntax: don't assume (operator) ~ means operator ^
The scanner assumed that ~ really meant ^, which may be helpful when
coming from C. But ~ is not a valid Go token, and pretending that it
should be ^ can lead to confusing error messages. Better to be upfront
about it and complain about the invalid character in the first place.

This was code "inherited" from the original yacc parser which was
derived from a C compiler. It's 10 years later and we can probably
assume that people are less confused about C and Go.

Fixes #23587.

Change-Id: I8d8f9b55b0dff009b75c1530d729bf9092c5aea6
Reviewed-on: https://go-review.googlesource.com/94160
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2018-02-15 16:41:24 +00:00
Ian Lance Taylor
0849dfd4a3 test: add new test that gccgo failed to compile
Updates #22305

Change-Id: I0e6bbd880599fc1b70d0378b746d162d4a846c65
Reviewed-on: https://go-review.googlesource.com/91556
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-02-15 03:37:20 +00:00
Robert Griesemer
1a22738749 cmd/compile/internal/syntax: more tolerant handling of missing function invocation in go/defer
Assume that an expression that is not a function call in a defer/go
statement is indeed a function that is just missing its invocation.
Report the error but continue with a sane syntax tree.

Fixes #23586.

Change-Id: Ib45ebac57c83b3e39ae4a1b137ffa291dec5b50d
Reviewed-on: https://go-review.googlesource.com/94156
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2018-02-15 01:48:16 +00:00
Matthew Dempsky
d3f6d11d84 cmd/compile: fix typechecking of untyped boolean expressions
Previously, if we typechecked a statement like

    var x bool = p1.f == p2.f && p1.g == p2.g

we would correctly update the '&&' node's type from 'untyped bool' to
'bool', but the '==' nodes would stay 'untyped bool'. This is
inconsistent, and caused consistency checks during walk to fail.

This CL doesn't pass toolstash because it seems to slightly affect the
register allocator's heuristics. (Presumably 'untyped bool's were
previously making it all the way through SSA?)

Fixes #23414.

Change-Id: Ia85f8cfc69b5ba35dfeb157f4edf57612ecc3285
Reviewed-on: https://go-review.googlesource.com/94022
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
2018-02-15 01:00:06 +00:00
Kunpei Sakai
bcb563f4db cmd/compile: allow converting defined string types to []rune
Fixes #23298

Change-Id: I107c6f3a80db83f063c0daf262c6e7f7492e4d4c
Reviewed-on: https://go-review.googlesource.com/87695
Run-TryBot: Kunpei Sakai <namusyaka@gmail.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2018-02-15 00:25:21 +00:00
Cherry Zhang
beeab6ac02 cmd/compile: fix go:uintptrescapes tag for unnamed parameters
The tag was overwritten by the code for special handling unnamed
parameters.

Fixes #23045.

Change-Id: Ie2e1db3e902a07a2bbbc2a3424cea300f0a42cc3
Reviewed-on: https://go-review.googlesource.com/82775
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2018-02-14 21:41:39 +00:00
Ian Lance Taylor
d1f679a6af test: add test case for incorrect gccgo compilation error
Updates #23489

Change-Id: Ie846ccfe4c4d9295857f5da6863ac8f2ac0f2f6a
Reviewed-on: https://go-review.googlesource.com/89935
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-02-14 20:13:22 +00:00
Ian Lance Taylor
034aca1cbb test: add a test that gccgo miscompiled
Updates #20923

Change-Id: Ia1210ea3dec39e5db2521aeafca24d6e731f0c93
Reviewed-on: https://go-review.googlesource.com/91657
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-02-14 20:13:07 +00:00
Ian Lance Taylor
d9fc1929e9 test: add test for rounding to positive zero
Per the language spec clarification in https://golang.org/cl/14727.

Updates #12576
Updates #12621

Change-Id: I1e459c3c11a571bd29582761faacaa9ca3178ba6
Reviewed-on: https://go-review.googlesource.com/91895
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Robert Griesemer <gri@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2018-02-14 20:13:05 +00:00
Keith Randall
755b36aa53 cmd/compile: fix constant folding of right shifts
The sub-word shifts need to sign-extend before shifting, to avoid
bringing in data from higher in the argument.

Fixes #23812

Change-Id: I0a95a0b49c48f3b40b85765bb4a9bb492be0cd73
Reviewed-on: https://go-review.googlesource.com/93716
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2018-02-14 00:03:36 +00:00
Emmanuel Odeke
25d22d9aba cmd/compile: report the struct type in invalid number of initializer values
Fixes #23732

Disambiguate "too few" or "too many" values in struct
initializer messages by reporting the name of the literal.

After:
issue23732.go:27:3: too few values in Foo literal
issue23732.go:34:12: too many values in Bar literal
issue23732.go:40:6: too few values in Foo literal
issue23732.go:40:12: too many values in Bar literal

Change-Id: Ieca37298441d907ac78ffe960c5ab55741a362ef
Reviewed-on: https://go-review.googlesource.com/93277
Run-TryBot: Emmanuel Odeke <emm.odeke@gmail.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2018-02-13 19:42:15 +00:00
Austin Clements
2010189407 runtime: remove legacy eager write barrier
Now that the buffered write barrier is implemented for all
architectures, we can remove the old eager write barrier
implementation. This CL removes the implementation from the runtime,
support in the compiler for calling it, and updates some compiler
tests that relied on the old eager barrier support. It also makes sure
that all of the useful comments from the old write barrier
implementation still have a place to live.

Fixes #22460.

Updates #21640 since this fixes the layering concerns of the write
barrier (but not the other things in that issue).

Change-Id: I580f93c152e89607e0a72fe43370237ba97bae74
Reviewed-on: https://go-review.googlesource.com/92705
Run-TryBot: Austin Clements <austin@google.com>
Reviewed-by: Rick Hudson <rlh@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2018-02-13 16:34:46 +00:00
Keith Randall
23e8e197b0 cmd/compile: use unsigned loads for multi-element comparisons
When loading multiple elements of an array into a single register,
make sure we treat them as unsigned.  When treated as signed, the
upper bits might all be set, causing the shift-or combo to clobber
the values higher in the register.

Fixes #23719.

Change-Id: Ic87da03e9bd0fe2c60bb214b99f846e4e9446052
Reviewed-on: https://go-review.googlesource.com/92335
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ilya Tocar <ilya.tocar@intel.com>
2018-02-06 18:24:33 +00:00
Cherry Zhang
43288467d2 test: add test for gccgo bug 23545
The fix is CL 91035.

Build only with gccgo at the moment, as it hits issue #23546.

Updates #23545.

Change-Id: I3a1367bb31b04773d31f71016f8fd7bd1855d7b5
Reviewed-on: https://go-review.googlesource.com/89735
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2018-01-31 20:03:31 +00:00
Keith Randall
7eaa8efbe4 cmd/compile: don't let spills clobber arguments
The compiler allows code to have multiple differently-typed views of a
single argument. For instance, if we have

func f(x float64) {
   y := *(*int64)(unsafe.Pointer(&x))
   ...
}

Then in SSA we get two OpArg ops, one with float64 type and one with
int64 type.

The compiler will try to reuse argument slots for spill slots. It
checks that the argument slot is dead by consulting an interference
graph.

When building the interference graph, we normally ignore cross-type
edges because the values on either end of that edge can't be allocated
to the same slot. (This is just a space-saving optimization.) This
rule breaks down when one of the values is an argument, because of the
multiple views described above. If we're spilling a float64, it is not
enough that the float64 version of x is dead; the int64 version of x
has to be dead also.

Remove the optimization of not recording interference edges if types
don't match. That optimization is incorrect if one of the values
connected by the edge is an argument.

Fixes #23522

Change-Id: I361f85d80fe3bc7249014ca2c3ec887c3dc30271
Reviewed-on: https://go-review.googlesource.com/89335
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2018-01-23 21:51:55 +00:00
Kunpei Sakai
e858a6b9f0 all: use Fatalf instead of Fatal if format is given
Change-Id: I30e9b938bb19ed4e674c3ea4a1cd389b9c4f0b88
Reviewed-on: https://go-review.googlesource.com/86875
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2018-01-10 01:35:45 +00:00
Cherry Zhang
7f1c4b3afb cmd/compile: disable "redundant zeroextensions" optimization for Select on AMD64
A Select Op could produce a value with upper 32 bits NOT zeroed,
for example, Div32 is lowered to (Select0 (DIVL x y)).

In theory, we could look into the argument of a Select to decide
whether the upper bits are zeroed. As it is late in release cycle,
just disable this optimization for Select for now.

Fixes #23305.

Change-Id: Icf665a2af9ccb0a7ba0ae00c683c9e349638bf85
Reviewed-on: https://go-review.googlesource.com/85736
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Ilya Tocar <ilya.tocar@intel.com>
2018-01-02 21:08:35 +00:00
Than McIntosh
841d865a56 cmd/compile: second attempt at fix for issue 23179
My previous fix for issue 23179 was incomplete; it turns out that if
an unnamed parameter is below a specific size threshold, it gets
register-promoted away by the compiler (hence not encountered during
some parts of DWARF inline info processing), but if it is sufficiently
large, it is allocated to the stack as a named variable and treated as
a regular parameter by DWARF generation. Interestingly, something in
the ppc64le build of k8s causes an unnamed parameter to be retained
(where on amd64 it is deleted), meaning that this wasn't caught in my
amd64 testing.

The fix is to insure that "_" params are treated in the same way that
"~r%d" return temps are when matching up post-optimization inlined
routine params with pre-inlining declarations. I've also updated the
test case to include a "_" parameter with a very large size, which
also triggers the bug on amd64.

Fixes #23179.

Change-Id: I961c84cc7a873ad3f8f91db098a5e13896c4856e
Reviewed-on: https://go-review.googlesource.com/84975
Run-TryBot: Than McIntosh <thanm@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Heschi Kreinick <heschi@google.com>
2017-12-20 20:39:16 +00:00
Than McIntosh
0447216316 cmd/compile: fix corner case in DWARF inline info generation
The helper routine for returning pre-inlining parameter declarations
wasn't properly handling the case where you have more than one
parameter named "_" in a function signature; this triggered a map
collision later on when the function was inlined and DWARF was
generated for the inlined routine instance.

Fixes #23179.

Change-Id: I12e5d6556ec5ce08e982a6b53666a4dcc1d22201
Reviewed-on: https://go-review.googlesource.com/84755
Run-TryBot: Than McIntosh <thanm@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Heschi Kreinick <heschi@google.com>
Reviewed-by: David Chase <drchase@google.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2017-12-19 19:00:42 +00:00
Russ Cox
c6ea277ac1 test: skip "# package/path" output from cmd/go in errchk
This allows errchk to be used with "go vet" output (as opposed to "go tool vet").

Change-Id: I0009a53c9cb74accd5bd3923c137d6dbf9e46326
Reviewed-on: https://go-review.googlesource.com/83836
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2017-12-13 21:32:01 +00:00
Matthew Dempsky
13bf4ada80 cmd/compile: remove broken inlining accounting code
We can't currently inline functions that contain closures anyway, so
just delete this budgeting code for now. Re-enable once we can (if
ever) inline functions with nested closures.

Updates #15561.
Fixes #23093.

Change-Id: Idc5f8e042ccfcc8921022e58d3843719d4ab821e
Reviewed-on: https://go-review.googlesource.com/83538
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
2017-12-12 20:26:33 +00:00
Matthew Dempsky
840fad13ec cmd/compile: fix unsafe.Pointer liveness for Syscall-like functions
The package unsafe docs say it's safe to convert an unsafe.Pointer to
uintptr in the argument list to an assembly function, but it was
erroneously only detecting normal pointers converted to unsafe.Pointer
and then to intptr.

Fixes #23051.

Change-Id: Id1be19f6d8f26f2d17ba815191717d2f4f899732
Reviewed-on: https://go-review.googlesource.com/82817
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-12-08 21:34:24 +00:00
Keith Randall
4c800f03c9 cmd/compile: fix large load/store offsets on 386
Pointer arithemetic is done mod 2^32 on 386, so we can just
drop the high bits of any large constant offsets.

The bounds check will make sure wraparounds are never observed.

Fixes #21655

Change-Id: I68ae5bbea9f02c73968ea2b21ca017e5ecb89223
Reviewed-on: https://go-review.googlesource.com/82675
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
2017-12-08 03:53:18 +00:00
Keith Randall
dd7cbf3a84 cmd/compile: fix map assignment with panicking right-hand side
Make sure that when we're assigning to a map, we evaluate the
right-hand side before we attempt to insert into the map.

We used to evaluate the left-hand side to a pointer-to-slot-in-bucket
(which as a side effect does len(m)++), then evaluate the right-hand side,
then do the assignment. That clearly isn't correct when the right-hand side
might panic.

Fixes #22881

Change-Id: I42a62870ff4bf480568c9bdbf0bb18958962bdf0
Reviewed-on: https://go-review.googlesource.com/81817
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2017-12-05 00:10:10 +00:00
Matthew Dempsky
2b9e7c1864 test: disable broken test for 1.10
This test was added recently as a regress test for the spec relaxation
in #9060, but doesn't work correctly yet. Disable for now to fix noopt
builders.

Updates #22444.

Change-Id: I45c521ae0da7ffb0c6859d6f7220c59828ac6149
Reviewed-on: https://go-review.googlesource.com/81775
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2017-12-04 19:29:14 +00:00
Than McIntosh
88c2fb9d04 cmd/compile: fix bug in DWARF inl handling of unused autos
The DWARF inline info generation hooks weren't properly
handling unused auto vars in certain cases, triggering an assert (now
fixed). Also with this change, introduce a new autom "flavor" to
use for autom entries that are added to insure that a specific
auto type makes it into the linker (this is a follow-on to the fix
for 22941).

Fixes #22962.

Change-Id: I7a2d8caf47f6ca897b12acb6a6de0eb25f5cac8f
Reviewed-on: https://go-review.googlesource.com/81557
Run-TryBot: Than McIntosh <thanm@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2017-12-04 18:36:11 +00:00
Robert Griesemer
088a9ad543 cmd/compile: permit indices of certain non-constant shifts
Per the decision for #14844, index expressions that are non-constant
shifts where the LHS operand is representable as an int are now valid.

Fixes #21693.

Change-Id: Ifafad2c0c65975e0200ce7e28d1db210e0eacd9d
Reviewed-on: https://go-review.googlesource.com/81277
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2017-12-01 20:39:50 +00:00
Than McIntosh
9372166faa cmd/compile: fix DWARF type symbol buglet
The code that generates the list of DWARF variables for a function
(params and autos) will emit a "no-location" entry in the DWARF for a
user var that appears in the original pre-optimization version of the
function but is no longer around when optimization is complete. The
intent is that if a GDB user types "print foo" (where foo has been
optimized out), the response will be "<optimized out>" as opposed to
"there is no such variable 'foo'). This change fixes said code to
include vars on the autom list for the function, to insure that the
type symbol for the variable makes it to the linker.

Fixes #22941.

Change-Id: Id29f1f39d68fbb798602dfd6728603040624fc41
Reviewed-on: https://go-review.googlesource.com/81415
Run-TryBot: Than McIntosh <thanm@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2017-12-01 18:52:50 +00:00
Cherry Zhang
dbb1d198ab cmd/compile: fix loop depth of range expression in escape analysis
ORANGE node's Right node is the expression it is ranging over,
which is evaluated before the loop. In the escape analysis,
we should walk this node without loop depth incremented.

Fixes #21709.

Change-Id: Idc1e4c76e39afb5a344d85f6b497930a488ce5cf
Reviewed-on: https://go-review.googlesource.com/80740
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
2017-11-30 13:45:18 +00:00
Matthew Dempsky
2f588ff08f cmd/compile: make -asmhdr work with type aliases
For "type T = U" we were accidentally emitting a #define for "U__size"
instead of "T__size".

Fixes #22877.

Change-Id: I5ed6757d697753ed6d944077c16150759f6e1285
Reviewed-on: https://go-review.googlesource.com/80759
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2017-11-29 20:40:41 +00:00
Matthew Dempsky
71a9c4430f cmd/compile: fix infinite recursion in isdirectiface
Fixes #22904.

Change-Id: Id504504eda7275c10d3c665add8b7ccd23f65820
Reviewed-on: https://go-review.googlesource.com/80301
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Emmanuel Odeke <emm.odeke@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-11-28 21:58:16 +00:00
Matthew Dempsky
3c375f1b7e cmd/compile, go/types: error if main.main is not a function
Fixes #21256.

Change-Id: I3af4c76e734c09d07f15525b793a544a7279b906
Reviewed-on: https://go-review.googlesource.com/79435
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
2017-11-22 19:14:31 +00:00
Keith Randall
48e207d518 cmd/compile: fix mapassign_fast* routines for pointer keys
The signature of the mapassign_fast* routines need to distinguish
the pointerness of their key argument.  If the affected routines
suspend part way through, the object pointed to by the key might
get garbage collected because the key is typed as a uint{32,64}.

This is not a problem for mapaccess or mapdelete because the key
in those situations do not live beyond the call involved.  If the
object referenced by the key is garbage collected prematurely, the
code still works fine.  Even if that object is subsequently reallocated,
it can't be written to the map in time to affect the lookup/delete.

Fixes #22781

Change-Id: I0bbbc5e9883d5ce702faf4e655348be1191ee439
Reviewed-on: https://go-review.googlesource.com/79018
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
Reviewed-by: Martin Möhrmann <moehrmann@google.com>
2017-11-22 04:30:27 +00:00
Austin Clements
e862f98d1e test: make inline_callers.go test not inline the runtime
CL 76551 modified inline_callers.go to build everything, including the
runtime, with -l=4. While that works in most places (and ideally
should work everywhere), it blows out the nosplit stack on
solaris/amd64.

Fix this by only building the test itself with -l=4.

This undoes some of the changes to this test from CL 73212, which
originally changed the go tool to rebuild all packages with the given
flags. This change modified the expected output of this test, so now
that we can go back to building only the test itself with inlining, we
revert these changes to the expected output. (That CL also changed
log.Fatalf to log.Printf, but didn't add "\n" to the end of the lines,
so this CL fixes that, too.)

Fixes #22797.

Change-Id: I6a91963a59ebe98edbe0921d8717af6b2c2191b0
Reviewed-on: https://go-review.googlesource.com/79197
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2017-11-22 00:52:54 +00:00
Emmanuel Odeke
5f29a7a705 cmd/compile: hint on wrong case-field names in composite literals
Improve the error message for wrong
case-field names in composite literals,
by mentioning the correct field name.

Given the program:
package main

type it struct {
        ID string
}

func main() {
        i1 := &it{id: "Bar"}
}

just like we do for usage of fields, we now
report wrongly cased fields as hints to give:

ts.go:8:14: unknown field 'id' in struct literal of type it (but does have ID)

instead of before:

ts.go:8:14: unknown field 'id' in struct literal of type it

Fixes #22794

Change-Id: I18cd70e75817025cb1df083503cae306e8d659fd
Reviewed-on: https://go-review.googlesource.com/78545
Run-TryBot: Emmanuel Odeke <emm.odeke@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2017-11-20 20:29:43 +00:00
Keith Randall
3abf117704 cmd/compile: add test for array decomposition
This test fails on 1.9.2, but is ok on tip.
CL 77331 has both the 1.9.2 fix and this test, and is on the 1.9 release branch.
This CL is just the test, and is on HEAD.  The buggy code doesn't exist on tip.

Update #22683

Change-Id: I04a24bd6c2d3068e18ca81da3347e2c1366f4447
Reviewed-on: https://go-review.googlesource.com/77332
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-11-13 20:22:22 +00:00
griesemer
ca2a886cba cmd/compile: record original and absolute file names for line directives
Also, with this change, error locations don't print absolute positions
in [] brackets following positions relative to line directives. To get
the absolute positions as well, specify the -L flag.

Fixes #22660.

Change-Id: I9ecfa254f053defba9c802222874155fa12fee2c
Reviewed-on: https://go-review.googlesource.com/77090
Reviewed-by: David Crawshaw <crawshaw@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2017-11-13 16:47:41 +00:00
Russ Cox
5993251c01 cmd/go: implement per-package asmflags, gcflags, ldflags, gccgoflags
It has always been problematic that there was no way to specify
tool flags that applied only to the build of certain packages;
it was only to specify flags for all packages being built.
The usual workaround was to install all dependencies of something,
then build just that one thing with different flags. Since the
dependencies appeared to be up-to-date, they were not rebuilt
with the different flags. The new content-based staleness
(up-to-date) checks see through this trick, because they detect
changes in flags. This forces us to address the underlying problem
of providing a way to specify per-package flags.

The solution is to allow -gcflags=pattern=flags, which means
that flags apply to packages matching pattern, in addition to the
usual -gcflags=flags, which is now redefined to apply only to
the packages named on the command line.

See #22527 for discussion and rationale.

Fixes #22527.

Change-Id: I6716bed69edc324767f707b5bbf3aaa90e8e7302
Reviewed-on: https://go-review.googlesource.com/76551
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
2017-11-09 15:04:04 +00:00
David Chase
a042221cdb cmd/compile: adjust Pos setting for "empty" blocks
Plain blocks that contain only uninteresting instructions
(that do not have reliable Pos information themselves)
need to have their Pos left unset so that they can
inherit it from their successors.  The "uninteresting"
test was not properly applied and not properly defined.
OpFwdRef does not appear in the ssa.html debugging output,
but at the time of the test these instructions did appear,
and it needs to be part of the test.

Fixes #22365.

Change-Id: I99e5b271acd8f6bcfe0f72395f905c7744ea9a02
Reviewed-on: https://go-review.googlesource.com/74252
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2017-11-08 22:39:49 +00:00
Ian Lance Taylor
a4c009f5ae cmd/compile: don't put Noalg types in typelinks
They could get picked up by reflect code, yielding the wrong type.

Fixes #22605

Change-Id: Ie11fb361ca7f3255e662037b3407565c8f0a2c4c
Reviewed-on: https://go-review.googlesource.com/76315
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2017-11-07 22:29:48 +00:00
griesemer
17ff23f7c8 cmd/compile/internal/syntax: better syntax errors for typos in if/switch/for headers
Be more pessimistic when parsing if/switch/for headers for better error
messages when things go wrong.

Fixes #22581.

Change-Id: Ibb99925291ff53f35021bc0a59a4c9a7f695a194
Reviewed-on: https://go-review.googlesource.com/76290
Run-TryBot: Robert Griesemer <gri@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2017-11-06 23:17:24 +00:00
Emmanuel Odeke
0c55495748 cmd/compile: lock in test for column numbers in unused error
Updates #21317

@mdempsky fixed issue #21317 with CL 66810,
so lock a test in to ensure we don't regress.

The test is manual for now before test/run.go
has support for matching column numbers so do
it old school and match expected output after
an exec.

Change-Id: I6c2a66ddf04248f79d17ed7033a3280d50e41562
Reviewed-on: https://go-review.googlesource.com/76150
Run-TryBot: Emmanuel Odeke <emm.odeke@gmail.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-11-06 21:32:06 +00:00
Austin Clements
3a446d8652 cmd/compile: []T where T is go:notinheap does not need write barriers
Currently, assigning a []T where T is a go:notinheap type generates an
unnecessary write barrier for storing the slice pointer.

This fixes this by teaching HasHeapPointer that this type does not
have a heap pointer, and tweaking the lowering of slice assignments so
the pointer store retains the correct type rather than simply lowering
it to a *uint8 store.

Change-Id: I8bf7c66e64a7fefdd14f2bd0de8a5a3596340bab
Reviewed-on: https://go-review.googlesource.com/76027
Run-TryBot: Austin Clements <austin@google.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-11-06 21:07:57 +00:00
Emmanuel Odeke
0ba4eba864 cmd/compile: test for omitted ICE diagnostics after normal messages
Updates #22389

@mdempsky's CL 70850 fixed the unnecessary
compile stack trace printing during ICE diagnostics.

This CL adds a test to lock in this behavior.

Change-Id: I9ce49923c80b78cb8c0bb5dc4af3c860a43d63ba
Reviewed-on: https://go-review.googlesource.com/74630
Run-TryBot: Emmanuel Odeke <emm.odeke@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2017-11-06 08:37:30 +00:00
Hugues Bruant
c4b65fa4cc cmd/compile: inline closures with captures
When inlining a closure with captured variables, walk up the
param chain to find the one that is defined inside the scope
into which the function is being inlined, and map occurrences
of the captures to temporary inlvars, similarly to what is
done for function parameters.

No noticeable impact on compilation speed and binary size.

Minor improvements to go1 benchmarks on darwin/amd64

name                     old time/op    new time/op    delta
BinaryTree17-4              2.59s ± 3%     2.58s ± 1%    ~     (p=0.470 n=19+19)
Fannkuch11-4                3.15s ± 2%     3.15s ± 1%    ~     (p=0.647 n=20+19)
FmtFprintfEmpty-4          43.7ns ± 3%    43.4ns ± 4%    ~     (p=0.178 n=18+20)
FmtFprintfString-4         74.0ns ± 2%    77.1ns ± 7%  +4.13%  (p=0.000 n=20+20)
FmtFprintfInt-4            77.2ns ± 3%    79.2ns ± 6%  +2.53%  (p=0.000 n=20+20)
FmtFprintfIntInt-4          112ns ± 4%     112ns ± 2%    ~     (p=0.672 n=20+19)
FmtFprintfPrefixedInt-4     136ns ± 1%     135ns ± 2%    ~     (p=0.827 n=16+20)
FmtFprintfFloat-4           232ns ± 2%     233ns ± 1%    ~     (p=0.194 n=20+20)
FmtManyArgs-4               490ns ± 2%     484ns ± 2%  -1.28%  (p=0.001 n=20+20)
GobDecode-4                6.68ms ± 2%    6.72ms ± 2%    ~     (p=0.113 n=20+19)
GobEncode-4                5.62ms ± 2%    5.71ms ± 2%  +1.64%  (p=0.000 n=20+19)
Gzip-4                      235ms ± 3%     236ms ± 2%    ~     (p=0.607 n=20+19)
Gunzip-4                   37.1ms ± 2%    36.8ms ± 3%    ~     (p=0.060 n=20+20)
HTTPClientServer-4         61.9µs ± 2%    62.7µs ± 4%  +1.24%  (p=0.007 n=18+19)
JSONEncode-4               12.5ms ± 2%    12.4ms ± 3%    ~     (p=0.192 n=20+20)
JSONDecode-4               51.6ms ± 3%    51.0ms ± 3%  -1.19%  (p=0.008 n=20+19)
Mandelbrot200-4            4.12ms ± 6%    4.06ms ± 5%    ~     (p=0.063 n=20+20)
GoParse-4                  3.12ms ± 5%    3.10ms ± 2%    ~     (p=0.402 n=19+19)
RegexpMatchEasy0_32-4      80.7ns ± 2%    75.1ns ± 9%  -6.94%  (p=0.000 n=17+20)
RegexpMatchEasy0_1K-4       197ns ± 2%     186ns ± 2%  -5.43%  (p=0.000 n=20+20)
RegexpMatchEasy1_32-4      77.5ns ± 4%    71.9ns ± 7%  -7.25%  (p=0.000 n=20+18)
RegexpMatchEasy1_1K-4       341ns ± 3%     341ns ± 3%    ~     (p=0.732 n=20+20)
RegexpMatchMedium_32-4      113ns ± 2%     112ns ± 3%    ~     (p=0.102 n=20+20)
RegexpMatchMedium_1K-4     36.6µs ± 2%    35.8µs ± 2%  -2.26%  (p=0.000 n=18+20)
RegexpMatchHard_32-4       1.75µs ± 3%    1.74µs ± 2%    ~     (p=0.473 n=20+19)
RegexpMatchHard_1K-4       52.6µs ± 2%    52.0µs ± 3%  -1.15%  (p=0.005 n=20+20)
Revcomp-4                   381ms ± 4%     377ms ± 2%    ~     (p=0.067 n=20+18)
Template-4                 57.3ms ± 2%    57.7ms ± 2%    ~     (p=0.108 n=20+20)
TimeParse-4                 291ns ± 3%     292ns ± 2%    ~     (p=0.585 n=20+20)
TimeFormat-4                314ns ± 3%     315ns ± 1%    ~     (p=0.681 n=20+20)
[Geo mean]                 47.4µs         47.1µs       -0.73%

name                     old speed      new speed      delta
GobDecode-4               115MB/s ± 2%   114MB/s ± 2%    ~     (p=0.115 n=20+19)
GobEncode-4               137MB/s ± 2%   134MB/s ± 2%  -1.63%  (p=0.000 n=20+19)
Gzip-4                   82.5MB/s ± 3%  82.4MB/s ± 2%    ~     (p=0.612 n=20+19)
Gunzip-4                  523MB/s ± 2%   528MB/s ± 3%    ~     (p=0.060 n=20+20)
JSONEncode-4              155MB/s ± 2%   156MB/s ± 3%    ~     (p=0.192 n=20+20)
JSONDecode-4             37.6MB/s ± 3%  38.1MB/s ± 3%  +1.21%  (p=0.007 n=20+19)
GoParse-4                18.6MB/s ± 4%  18.7MB/s ± 2%    ~     (p=0.405 n=19+19)
RegexpMatchEasy0_32-4     396MB/s ± 2%   426MB/s ± 8%  +7.56%  (p=0.000 n=17+20)
RegexpMatchEasy0_1K-4    5.18GB/s ± 2%  5.48GB/s ± 2%  +5.79%  (p=0.000 n=20+20)
RegexpMatchEasy1_32-4     413MB/s ± 4%   444MB/s ± 6%  +7.46%  (p=0.000 n=20+19)
RegexpMatchEasy1_1K-4    3.00GB/s ± 3%  3.00GB/s ± 3%    ~     (p=0.678 n=20+20)
RegexpMatchMedium_32-4   8.82MB/s ± 2%  8.90MB/s ± 3%  +0.99%  (p=0.044 n=20+20)
RegexpMatchMedium_1K-4   28.0MB/s ± 2%  28.6MB/s ± 2%  +2.32%  (p=0.000 n=18+20)
RegexpMatchHard_32-4     18.3MB/s ± 3%  18.4MB/s ± 2%    ~     (p=0.482 n=20+19)
RegexpMatchHard_1K-4     19.5MB/s ± 2%  19.7MB/s ± 3%  +1.18%  (p=0.004 n=20+20)
Revcomp-4                 668MB/s ± 4%   674MB/s ± 2%    ~     (p=0.066 n=20+18)
Template-4               33.8MB/s ± 2%  33.6MB/s ± 2%    ~     (p=0.104 n=20+20)
[Geo mean]                124MB/s        126MB/s       +1.54%

Updates #15561
Updates #18270

Change-Id: I980086efe28b36aa27f81577065e2a729ff03d4e
Reviewed-on: https://go-review.googlesource.com/72490
Reviewed-by: Hugues Bruant <hugues.bruant@gmail.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-11-05 04:18:05 +00:00
Hugues Bruant
483e298daa cmd/compile: fix reassignment check
CL 65071 enabled inlining for local closures with no captures.

To determine safety of inlining a call sites, we check whether the
variable holding the closure has any assignments after its original
definition.

Unfortunately, that check did not catch OAS2MAPR and OAS2DOTTYPE,
leading to incorrect inlining when a variable holding a closure was
subsequently reassigned through a type conversion or a 2-valued map
access.

There was another more subtle issue wherein reassignment check would
always return a false positive for closure calls inside other
closures. This was caused by the Name.Curfn field of local variables
pointing to the OCLOSURE node instead of the corresponding ODCLFUNC,
which resulted in reassigned walking an empty Nbody and thus never
seeing any reassignments.

This CL fixes these oversights and adds many more tests for closure
inlining which ensure not only that inlining triggers but also the
correctness of the resulting code.

Updates #15561

Change-Id: I74bdae849c4ecfa328546d6d62b512e8d54d04ce
Reviewed-on: https://go-review.googlesource.com/75770
Reviewed-by: Hugues Bruant <hugues.bruant@gmail.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-11-03 20:09:26 +00:00
griesemer
25159d3af9 cmd/compile: avoid spurious errors for invalid map key types
Instead of trying to validate map key types eagerly in some
cases, delay their validation to the end of type-checking,
when we all type information is present.

Passes go build -toolexec 'toolstash -cmp' -a std .

Fixes #21273.
Fixes #21657.

Change-Id: I532369dc91c6adca1502d6aa456bb06b57e6c7ff
Reviewed-on: https://go-review.googlesource.com/75310
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2017-11-02 23:53:38 +00:00
Martin Möhrmann
fbfc2031a6 cmd/compile: specialize map creation for small hint sizes
Handle make(map[any]any) and make(map[any]any, hint) where
hint <= BUCKETSIZE special to allow for faster map initialization
and to improve binary size by using runtime calls with fewer arguments.

Given hint is smaller or equal to BUCKETSIZE in which case
overLoadFactor(hint, 0)  is false and no buckets would be allocated by makemap:
* If hmap needs to be allocated on the stack then only hmap's hash0
  field needs to be initialized and no call to makemap is needed.
* If hmap needs to be allocated on the heap then a new special
  makehmap function will allocate hmap and intialize hmap's
  hash0 field.

Reduces size of the godoc by ~36kb.

AMD64
name         old time/op    new time/op    delta
NewEmptyMap    16.6ns ± 2%     5.5ns ± 2%  -66.72%  (p=0.000 n=10+10)
NewSmallMap    64.8ns ± 1%    56.5ns ± 1%  -12.75%  (p=0.000 n=9+10)

Updates #6853

Change-Id: I624e90da6775afaa061178e95db8aca674f44e9b
Reviewed-on: https://go-review.googlesource.com/61190
Run-TryBot: Martin Möhrmann <moehrmann@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2017-11-02 17:03:45 +00:00
Cherry Zhang
f33f20ef1f test: fix and re-enable nosplit.go
The test was skipped because it did not work on AMD64 with
frame pointer enabled, and accidentally skipped on other
architectures. Now frame pointer is the default on AMD64.
Update the test to work with frame pointer. Now the test
is skipped only when frame pointer is NOT enabled on AMD64.

Fixes #18317.

Change-Id: I724cb6874e562f16e67ce5f389a1d032a2003115
Reviewed-on: https://go-review.googlesource.com/68610
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2017-10-31 19:12:11 +00:00
Russ Cox
84dc501d20 test/run: use go tool compile + link instead of go run when possible
This cuts 6 seconds off all.bash with the new go command.
Not a ton, but also an easy 6 seconds to grab.

The -tags=use_go_run in the misc/cgo tests is just some
go command flag that will make run.go use go run,
but without making everything look stale.
(Those tests have relative imports,
so go tool compile+link is not enough.)

Change-Id: I43bf4bb661d3adde2b2d4aad5e8f64b97bc69ba9
Reviewed-on: https://go-review.googlesource.com/73994
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-10-31 13:21:05 +00:00
Russ Cox
7dea509703 cmd/go: switch to entirely content-based staleness determination
This CL changes the go command to base all its rebuilding decisions
on the content of the files being processed and not their file system
modification times. It also eliminates the special handling of release
toolchains, which were previously considered always up-to-date
because modification time order could not be trusted when unpacking
a pre-built release.

The go command previously tracked "build IDs" as a backup to
modification times, to catch changes not reflected in modification times.
For example, if you remove one .go file in a package with multiple .go
files, there is no modification time remaining in the system that indicates
that the installed package is out of date. The old build ID was the hash
of a list of file names and a few other factors, expected to change if
those factors changed.

This CL moves to using this kind of build ID as the only way to
detect staleness, making sure that the build ID hash includes all
possible factors that need to influence the rebuild decision.

One such factor is the compiler flags. As of this CL, if you run

	go build -gcflags -N cmd/gofmt

you will get a gofmt where every package is built with -N,
regardless of what may or may not be installed already.

Another such factor is the linker flags. As of this CL, if you run

	go install myprog
	go install -ldflags=-s myprog

the second go install will now correctly build a new myprog with
the updated linker flags. (Previously the installed myprog appeared
up-to-date, because the ldflags were not included in the build ID.)

Because we have more precise information we can also validate whether
the target of a "go test -c" operation is already the right binary and
therefore can avoid a rebuild.

This CL sets us up for having a more general build artifact cache,
maybe even a step toward not having a pkg directory with .a files,
but this CL does not take that step. For now the result of go install
is the same as it ever was; we just do a better job of what needs to
be installed.

This CL does slow down builds a small amount by reading all the
dependent source files in full. (The go command already read the
beginning of every dependent source file to discover build tags
and imports.) On my MacBook Pro, before this CL all.bash takes
3m58s, while after this CL and a few optimizations stacked above it
all.bash takes 4m28s. Given that CL 73850 cut 1m43s off the all.bash
time earlier today, we can afford adding 30s back for now.
More optimizations are planned that should make the go command
more efficient than it was even before this CL.

Fixes #15799.
Fixes #18369.
Fixes #19340.
Fixes #21477.

Change-Id: I10d7ca0e31ca3f58aabb9b1f11e2e3d9d18f0bc9
Reviewed-on: https://go-review.googlesource.com/73212
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
2017-10-31 13:19:38 +00:00
Russ Cox
2beb173e98 all: respect $GO_GCFLAGS during run.bash
If the go install doesn't use the same flags as the main build
it can overwrite the installed standard library, leading to
flakiness and slow future tests.

Force uses of 'go install' etc to propagate $GO_GCFLAGS
or disable them entirely, to avoid problems.

As I understand it, the main place this happens is the ssacheck builder.
If there are other uses that need to run some of the now-disabled
tests we can reenable fixed tests in followup CLs.

Change-Id: Ib860a253539f402f8a96a3c00ec34f0bbf137c9a
Reviewed-on: https://go-review.googlesource.com/74470
Reviewed-by: David Crawshaw <crawshaw@golang.org>
2017-10-31 13:19:15 +00:00
David Chase
b4c3fe7b04 cmd/compile: adjust expectations of test for issue 18902
The test for #18902 reads the assembly stream to be sure
that the line number does not change too often (this is an
indication that debugging the code will be unpleasant and
that the compiler is probably getting line numbers "wrong").

It checks that it is getting "enough" input, but the
compiler has gotten enough better since the test was written
that it now fails for lack of enough input.  The old
threshould was 200 instructions, the new one is 150 (the
minimum observed input is on arm64 with 184 instructions).

Fixes #22494.

Change-Id: Ibba7e9ff4ab6a7be369e5dd5859d150b7db94653
Reviewed-on: https://go-review.googlesource.com/74357
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
2017-10-30 20:27:09 +00:00
Keith Randall
0153a4130d cmd/compile: fix runtime.KeepAlive
KeepAlive needs to introduce a use of the spill of the
value it is keeping alive.  Without that, we don't guarantee
that the spill dominates the KeepAlive.

This bug was probably introduced with the code to move spills
down to the dominator of the restores, instead of always spilling
just after the value itself (CL 34822).

Fixes #22458.

Change-Id: I94955a21960448ffdacc4df775fe1213967b1d4c
Reviewed-on: https://go-review.googlesource.com/74210
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Reviewed-by: David Chase <drchase@google.com>
2017-10-30 19:55:02 +00:00
Austin Clements
7e343134d3 cmd/compile: compiler support for buffered write barrier
This CL implements the compiler support for calling the buffered write
barrier added by the previous CL.

Since the buffered write barrier is only implemented on amd64 right
now, this still supports the old, eager write barrier as well. There's
little overhead to supporting both and this way a few tests in
test/fixedbugs that expect to have liveness maps at write barrier
calls can easily opt-in to the old, eager barrier.

This significantly improves the performance of the write barrier:

name             old time/op  new time/op  delta
WriteBarrier-12  73.5ns ±20%  19.2ns ±27%  -73.90%  (p=0.000 n=19+18)

It also reduces the size of binaries because the write barrier call is
more compact:

name        old object-bytes  new object-bytes  delta
Template           398k ± 0%         393k ± 0%  -1.14%  (p=0.008 n=5+5)
Unicode            208k ± 0%         206k ± 0%  -1.00%  (p=0.008 n=5+5)
GoTypes           1.18M ± 0%        1.15M ± 0%  -2.00%  (p=0.008 n=5+5)
Compiler          4.05M ± 0%        3.88M ± 0%  -4.26%  (p=0.008 n=5+5)
SSA               8.25M ± 0%        8.11M ± 0%  -1.59%  (p=0.008 n=5+5)
Flate              228k ± 0%         224k ± 0%  -1.83%  (p=0.008 n=5+5)
GoParser           295k ± 0%         284k ± 0%  -3.62%  (p=0.008 n=5+5)
Reflect           1.00M ± 0%        0.99M ± 0%  -0.70%  (p=0.008 n=5+5)
Tar                339k ± 0%         333k ± 0%  -1.67%  (p=0.008 n=5+5)
XML                404k ± 0%         395k ± 0%  -2.10%  (p=0.008 n=5+5)
[Geo mean]         704k              690k       -2.00%

name        old exe-bytes     new exe-bytes     delta
HelloSize         1.05M ± 0%        1.04M ± 0%  -1.55%  (p=0.008 n=5+5)

https://perf.golang.org/search?q=upload:20171027.1

(Amusingly, this also reduces compiler allocations by 0.75%, which,
combined with the better write barrier, speeds up the compiler overall
by 2.10%. See the perf link.)

It slightly improves the performance of most of the go1 benchmarks and
improves the performance of the x/benchmarks:

name                      old time/op    new time/op    delta
BinaryTree17-12              2.40s ± 1%     2.47s ± 1%  +2.69%  (p=0.000 n=19+19)
Fannkuch11-12                2.95s ± 0%     2.95s ± 0%  +0.21%  (p=0.000 n=20+19)
FmtFprintfEmpty-12          41.8ns ± 4%    41.4ns ± 2%  -1.03%  (p=0.014 n=20+20)
FmtFprintfString-12         68.7ns ± 2%    67.5ns ± 1%  -1.75%  (p=0.000 n=20+17)
FmtFprintfInt-12            79.0ns ± 3%    77.1ns ± 1%  -2.40%  (p=0.000 n=19+17)
FmtFprintfIntInt-12          127ns ± 1%     123ns ± 3%  -3.42%  (p=0.000 n=20+20)
FmtFprintfPrefixedInt-12     152ns ± 1%     150ns ± 1%  -1.02%  (p=0.000 n=18+17)
FmtFprintfFloat-12           211ns ± 1%     209ns ± 0%  -0.99%  (p=0.000 n=20+16)
FmtManyArgs-12               500ns ± 0%     496ns ± 0%  -0.73%  (p=0.000 n=17+20)
GobDecode-12                6.44ms ± 1%    6.53ms ± 0%  +1.28%  (p=0.000 n=20+19)
GobEncode-12                5.46ms ± 0%    5.46ms ± 1%    ~     (p=0.550 n=19+20)
Gzip-12                      220ms ± 1%     216ms ± 0%  -1.75%  (p=0.000 n=19+19)
Gunzip-12                   38.8ms ± 0%    38.6ms ± 0%  -0.30%  (p=0.000 n=18+19)
HTTPClientServer-12         79.0µs ± 1%    78.2µs ± 1%  -1.01%  (p=0.000 n=20+20)
JSONEncode-12               11.9ms ± 0%    11.9ms ± 0%  -0.29%  (p=0.000 n=20+19)
JSONDecode-12               52.6ms ± 0%    52.2ms ± 0%  -0.68%  (p=0.000 n=19+20)
Mandelbrot200-12            3.69ms ± 0%    3.68ms ± 0%  -0.36%  (p=0.000 n=20+20)
GoParse-12                  3.13ms ± 1%    3.18ms ± 1%  +1.67%  (p=0.000 n=19+20)
RegexpMatchEasy0_32-12      73.2ns ± 1%    72.3ns ± 1%  -1.19%  (p=0.000 n=19+18)
RegexpMatchEasy0_1K-12       241ns ± 0%     239ns ± 0%  -0.83%  (p=0.000 n=17+16)
RegexpMatchEasy1_32-12      68.6ns ± 1%    69.0ns ± 1%  +0.47%  (p=0.015 n=18+16)
RegexpMatchEasy1_1K-12       364ns ± 0%     361ns ± 0%  -0.67%  (p=0.000 n=16+17)
RegexpMatchMedium_32-12      104ns ± 1%     103ns ± 1%  -0.79%  (p=0.001 n=20+15)
RegexpMatchMedium_1K-12     33.8µs ± 3%    34.0µs ± 2%    ~     (p=0.267 n=20+19)
RegexpMatchHard_32-12       1.64µs ± 1%    1.62µs ± 2%  -1.25%  (p=0.000 n=19+18)
RegexpMatchHard_1K-12       49.2µs ± 0%    48.7µs ± 1%  -0.93%  (p=0.000 n=19+18)
Revcomp-12                   391ms ± 5%     396ms ± 7%    ~     (p=0.154 n=19+19)
Template-12                 63.1ms ± 0%    59.5ms ± 0%  -5.76%  (p=0.000 n=18+19)
TimeParse-12                 307ns ± 0%     306ns ± 0%  -0.39%  (p=0.000 n=19+17)
TimeFormat-12                325ns ± 0%     323ns ± 0%  -0.50%  (p=0.000 n=19+19)
[Geo mean]                  47.3µs         46.9µs       -0.67%

https://perf.golang.org/search?q=upload:20171026.1

name                       old time/op  new time/op  delta
Garbage/benchmem-MB=64-12  2.25ms ± 1%  2.20ms ± 1%  -2.31%  (p=0.000 n=18+18)
HTTP-12                    12.6µs ± 0%  12.6µs ± 0%  -0.72%  (p=0.000 n=18+17)
JSON-12                    11.0ms ± 0%  11.0ms ± 1%  -0.68%  (p=0.000 n=17+19)

https://perf.golang.org/search?q=upload:20171026.2

Updates #14951.
Updates #22460.

Change-Id: Id4c0932890a1d41020071bec73b8522b1367d3e7
Reviewed-on: https://go-review.googlesource.com/73712
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2017-10-30 18:12:46 +00:00
Austin Clements
b78b54ff83 cmd/compile: elide write barriers for copy of notinheap pointers
Currently copy and append for types containing only scalars and
notinheap pointers still get compiled to have write barriers, even
though those write barriers are unnecessary. Fix these to use
HasHeapPointer instead of just Haspointer so that they elide write
barriers when possible.

This fixes the unnecessary write barrier in runtime.recordspan when it
grows the h.allspans slice. This is important because recordspan gets
called (*very* indirectly) from (*gcWork).tryGet, which is
go:nowritebarrierrec. Unfortunately, the compiler's analysis has no
hope of seeing this because it goes through the indirect call
fixalloc.first, but I saw it happen.

Change-Id: Ieba3abc555a45f573705eab780debcfe5c4f5dd1
Reviewed-on: https://go-review.googlesource.com/73413
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2017-10-29 20:21:49 +00:00
Austin Clements
316e3036a7 cmd/compile: make HasHeapPointer recursive
Currently (*Type).HasHeapPointer only ignores pointers go:notinheap
types if the type itself is a pointer to a go:notinheap type. However,
if it's some other type that contains pointers where all of those
pointers are go:notinheap, it will conservatively return true. As a
result, we'll use write barriers where they aren't needed, for example
calling typedmemmove instead of just memmove on structs that contain
only go:notinheap pointers.

Fix this by making HasHeapPointer walk the whole type looking for
pointers that aren't marked go:notinheap.

Change-Id: Ib8c6abf6f7a20f34969d1d402c5498e0b990be59
Reviewed-on: https://go-review.googlesource.com/73412
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2017-10-29 20:21:47 +00:00
Austin Clements
5a4b6bce37 cmd/compile: improve coverage of nowritebarrierrec check
The current go:nowritebarrierrec checker has two problems that limit
its coverage:

1. It doesn't understand that systemstack calls its argument, which
means there are several cases where we fail to detect prohibited write
barriers.

2. It only observes calls in the AST, so calls constructed during
lowering by SSA aren't followed.

This CL completely rewrites this checker to address these issues.

The current checker runs entirely after walk and uses visitBottomUp,
which introduces several problems for checking across systemstack.
First, visitBottomUp itself doesn't understand systemstack calls, so
the callee may be ordered after the caller, causing the checker to
fail to propagate constraints. Second, many systemstack calls are
passed a closure, which is quite difficult to resolve back to the
function definition after transformclosure and walk have run. Third,
visitBottomUp works exclusively on the AST, so it can't observe calls
created by SSA.

To address these problems, this commit splits the check into two
phases and rewrites it to use a call graph generated during SSA
lowering. The first phase runs before transformclosure/walk and simply
records systemstack arguments when they're easy to get. Then, it
modifies genssa to record static call edges at the point where we're
lowering to Progs (which is the latest point at which position
information is conveniently available). Finally, the second phase runs
after all functions have been lowered and uses a direct BFS walk of
the call graph (combining systemstack calls with static calls) to find
prohibited write barriers and construct nice error messages.

Fixes #22384.
For #22460.

Change-Id: I39668f7f2366ab3c1ab1a71eaf25484d25349540
Reviewed-on: https://go-review.googlesource.com/72773
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2017-10-29 19:36:44 +00:00
Ian Lance Taylor
6222997047 test: add type alias test that caused gccgo to crash
Change-Id: I3b388e4ac05ace5b7768ade03df2bee5bcc26ba8
Reviewed-on: https://go-review.googlesource.com/73790
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
2017-10-26 22:52:53 +00:00
griesemer
c74712b3b2 test: add test cases for method expressions with literal receiver types
For #9060.

Change-Id: Ibd0f047083f3c98cec96c655a3e2024df8e1d2a0
Reviewed-on: https://go-review.googlesource.com/73554
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-10-26 03:47:37 +00:00
Keith Randall
40649e6979 cmd/compile: make sure not to use SP as an index register
...because that's an illegal addressing mode.

I double-checked handling of this code, and 387 is the only
place where this check is missing.

Fixes #22429

Change-Id: I2284fe729ea86251c6af2f04076ddf7a5e66367c
Reviewed-on: https://go-review.googlesource.com/73551
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-10-26 02:45:05 +00:00
Matthew Dempsky
efa9efe8e4 cmd/compile: silence unnecessary unsafe error
If n.Type==nil after typechecking, then we should have already
reported a more useful error somewhere else. Just return 0 in
evalunsafe without trying to do anything else that's likely to cause
problems.

Also, further split out issue7525.go into more test files, because
cmd/compile reports at most one typechecking loop per compilation
unit.

Fixes #22351.

Change-Id: I3ebf505f72c48fcbfef5ec915606224406026597
Reviewed-on: https://go-review.googlesource.com/72251
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>
Reviewed-by: Robert Griesemer <gri@golang.org>
2017-10-24 02:28:02 +00:00
Dhananjay Nakrani
4c8e8fc301 cmd/compile: fix segfault in race instrumentation
Fixes #13265.

Change-Id: I792eb4ee26bef8a56e279e23f9802cb39019e0d0
Reviewed-on: https://go-review.googlesource.com/34929
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-10-18 16:46:18 +00:00
griesemer
0b2cb89196 cmd/compile/internal/syntax: better recovery after missing closing parentheses
Fine-tune skipping of tokens after missing closing parentheses in lists.

Fixes #22164.

Change-Id: I575d86e21048cd40340a2c08399e8b0deec337cf
Reviewed-on: https://go-review.googlesource.com/71250
Run-TryBot: Robert Griesemer <gri@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2017-10-17 01:04:56 +00:00
Martin Möhrmann
743117a85e cmd/compile: simplify slice/array range loops for some element sizes
In range loops over slices and arrays besides a variable to track the
index an extra variable containing the address of the current element
is used. To compute a pointer to the next element the elements size is
added to the address.

On 386 and amd64 an element of size 1, 2, 4 or 8 bytes can by copied
from an array using a MOV instruction with suitable addressing mode
that uses the start address of the array, the index of the element and
element size as scaling factor. Thereby, for arrays and slices with
suitable element size we can avoid keeping and incrementing an extra
variable to compute the next elements address.

Shrinks cmd/go by 4 kilobytes.

AMD64:
name                   old time/op    new time/op    delta
BinaryTree17              2.66s ± 7%     2.54s ± 0%  -4.53%  (p=0.000 n=10+8)
Fannkuch11                3.02s ± 1%     3.02s ± 1%    ~     (p=0.579 n=10+10)
FmtFprintfEmpty          45.6ns ± 1%    42.2ns ± 1%  -7.46%  (p=0.000 n=10+10)
FmtFprintfString         69.8ns ± 1%    70.4ns ± 1%  +0.84%  (p=0.041 n=10+10)
FmtFprintfInt            80.1ns ± 1%    79.0ns ± 1%  -1.35%  (p=0.000 n=10+10)
FmtFprintfIntInt          127ns ± 1%     125ns ± 1%  -1.00%  (p=0.007 n=10+9)
FmtFprintfPrefixedInt     158ns ± 2%     152ns ± 1%  -4.11%  (p=0.000 n=10+10)
FmtFprintfFloat           218ns ± 1%     214ns ± 1%  -1.61%  (p=0.000 n=10+10)
FmtManyArgs               508ns ± 1%     504ns ± 1%  -0.93%  (p=0.001 n=9+10)
GobDecode                6.76ms ± 1%    6.78ms ± 1%    ~     (p=0.353 n=10+10)
GobEncode                5.84ms ± 1%    5.77ms ± 1%  -1.31%  (p=0.000 n=10+9)
Gzip                      223ms ± 1%     218ms ± 1%  -2.39%  (p=0.000 n=10+10)
Gunzip                   40.3ms ± 1%    40.4ms ± 3%    ~     (p=0.796 n=10+10)
HTTPClientServer         73.5µs ± 0%    73.3µs ± 0%  -0.28%  (p=0.000 n=10+9)
JSONEncode               12.7ms ± 1%    12.6ms ± 8%    ~     (p=0.173 n=8+10)
JSONDecode               57.5ms ± 1%    56.1ms ± 2%  -2.40%  (p=0.000 n=10+10)
Mandelbrot200            3.80ms ± 1%    3.86ms ± 6%    ~     (p=0.579 n=10+10)
GoParse                  3.25ms ± 1%    3.23ms ± 1%    ~     (p=0.052 n=10+10)
RegexpMatchEasy0_32      74.4ns ± 1%    76.9ns ± 1%  +3.39%  (p=0.000 n=10+10)
RegexpMatchEasy0_1K       243ns ± 2%     248ns ± 1%  +1.86%  (p=0.000 n=10+8)
RegexpMatchEasy1_32      71.0ns ± 2%    72.8ns ± 1%  +2.55%  (p=0.000 n=10+10)
RegexpMatchEasy1_1K       370ns ± 1%     383ns ± 0%  +3.39%  (p=0.000 n=10+9)
RegexpMatchMedium_32      107ns ± 0%     113ns ± 1%  +5.33%  (p=0.000 n=6+10)
RegexpMatchMedium_1K     35.0µs ± 1%    36.0µs ± 1%  +3.13%  (p=0.000 n=10+10)
RegexpMatchHard_32       1.65µs ± 1%    1.69µs ± 1%  +2.23%  (p=0.000 n=10+9)
RegexpMatchHard_1K       49.8µs ± 1%    50.6µs ± 1%  +1.59%  (p=0.000 n=10+10)
Revcomp                   398ms ± 1%     396ms ± 1%  -0.51%  (p=0.043 n=10+10)
Template                 63.4ms ± 1%    60.8ms ± 0%  -4.11%  (p=0.000 n=10+9)
TimeParse                 318ns ± 1%     322ns ± 1%  +1.10%  (p=0.005 n=10+10)
TimeFormat                323ns ± 1%     336ns ± 1%  +4.15%  (p=0.000 n=10+10)

Updates: #15809.

Change-Id: I55915aaf6d26768e12247f8a8edf14e7630726d1
Reviewed-on: https://go-review.googlesource.com/38061
Run-TryBot: Martin Möhrmann <moehrmann@google.com>
Reviewed-by: Keith Randall <khr@golang.org>
2017-10-13 14:52:04 +00:00
Tobias Klauser
fd9fac2c7c cmd/compile: add two error position tests for the typechecker
Follow CL 41477 and add two more line position tests for yyerror calls
in the typechecker which are currently not tested.

Update #19683

Change-Id: Iacd865195a3bfba87d8c22655382af267aba47a9
Reviewed-on: https://go-review.googlesource.com/70251
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
2017-10-12 20:50:20 +00:00
Ian Lance Taylor
56dec8dde2 test: add test case that gccgo miscompiled
Error was

main.go:7:11: error: import error at 162: expected ‘<type ’

Change-Id: Iacfe4bfa003d7708a21ebc89ad1ab2d4a3b041a8
Reviewed-on: https://go-review.googlesource.com/70290
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
2017-10-12 19:02:09 +00:00
Matthew Dempsky
a509cae90d cmd/compile: record InlCost in export data
Previously, we were treating cross-package function calls as free for
inlining budgeting.

In theory, we should be able to recompute InlCost from the
exported/reimported function bodies. However, that process mutates the
structure of the Node AST enough that it doesn't preserve InlCost. To
avoid unexpected issues, just record and restore InlCost in the export
data.

Fixes #19261.

Change-Id: Iac2bc0d32d4f948b64524aca657051f9fc96d92d
Reviewed-on: https://go-review.googlesource.com/70151
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Robert Griesemer <gri@golang.org>
2017-10-11 23:20:44 +00:00
Hugues Bruant
4f70a2a699 cmd/compile: inline calls to local closures
Calls to a closure held in a local, non-escaping,
variable can be inlined, provided the closure body
can be inlined and the variable is never written to.

The current implementation has the following limitations:

 - closures with captured variables are not inlined because
   doing so naively triggers invariant violation in the SSA
   phase
 - re-assignment check is currently approximated by checking
   the Addrtaken property of the variable which should be safe
   but may miss optimization opportunities if the address is
   not used for a write before the invocation

Updates #15561

Change-Id: I508cad5d28f027bd7e933b1f793c14dcfef8b5a1
Reviewed-on: https://go-review.googlesource.com/65071
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Hugues Bruant <hugues.bruant@gmail.com>
Reviewed-by: Keith Randall <khr@golang.org>
2017-10-11 22:32:36 +00:00
Cherry Zhang
70576947fd test: skip issue22200b.go on mipsle
It should be skipped on 32-bit architectures.

Change-Id: If7a64b9e90e47c3e8734dd62729bfd2944ae926c
Reviewed-on: https://go-review.googlesource.com/70071
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
2017-10-11 20:37:23 +00:00
Keith Randall
e130dcf051 cmd/compile: abort earlier if stack frame too large
If the stack frame is too large, abort immediately.
We used to generate code first, then abort.
In issue 22200, generating code raised a panic
so we got an ICE instead of an error message.

Change the max frame size to 1GB (from 2GB).
Stack frames between 1.1GB and 2GB didn't used to work anyway,
the pcln table generation would have failed and generated an ICE.

Fixes #22200

Change-Id: I1d918ab27ba6ebf5c87ec65d1bccf973f8c8541e
Reviewed-on: https://go-review.googlesource.com/69810
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-10-11 18:24:13 +00:00
Keith Randall
624630b824 cmd/compile: fold constant comparisions into SETxxmem ops.
Fixes #22198

Change-Id: I5cb91c73069af8b16a2580d28756efd58c84b690
Reviewed-on: https://go-review.googlesource.com/69990
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2017-10-11 18:23:09 +00:00
griesemer
68e390304e cmd/compile/internal/syntax: consider function nesting for error recovery
This re-enables functionality that inadvertently was disabled in the
(long) past.

Also, don't perform branch checks if we had errors in a function
to avoid spurious errors or (worst-case) crashes.

Slightly modified test/fixedbugs/issue14006.go to make sure the
test still reports invalid label errors (the surrounding function
must be syntactically correct).

Change-Id: Id5642930877d7cf3400649094ec75c753b5084b7
Reviewed-on: https://go-review.googlesource.com/69770
Run-TryBot: Robert Griesemer <gri@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-10-11 00:29:58 +00:00
Cherry Zhang
d63de28711 cmd/compile: intrinsify atomics on MIPS64
Change-Id: Ica65b7a52af9558a05d0a0e1dff0f9ec838f4117
Reviewed-on: https://go-review.googlesource.com/68830
Run-TryBot: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Keith Randall <khr@golang.org>
2017-10-10 19:43:38 +00:00
Matthew Dempsky
f58c6c9915 cmd/compile: remove outdated TODO about inlining
We've supported inlining methods called as functions for a while now.

Change-Id: I53fba426e45f91d65a38f00456c2ae1527372b50
Reviewed-on: https://go-review.googlesource.com/69530
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
2017-10-10 17:53:22 +00:00
griesemer
b77d9fe0ea cmd/compile: better error message for assignment mismatches
Keep left-to-right order when referring to the number of
variables and values involved.

Fixes #22159.

Change-Id: Iccca12d3222f9d5e049939a9ccec07513c393faa
Reviewed-on: https://go-review.googlesource.com/68690
Reviewed-by: Russ Cox <rsc@golang.org>
2017-10-06 16:35:44 +00:00
Cherry Zhang
a92a77c56f cmd/internal/obj/arm64: fix handling of unaligned offset between 256 and 504
C_PPAUTO was matching offsets that is a multiple 8. But this
condition is dropped in CL 55610, causing unaligned offset
between 256 and 504 mistakenly matched to some classes, e.g.
C_UAUTO8K. This CL restores this condition, also fixes an
error that C_PPAUTO shouldn't match C_PSAUTO, because the
latter is not guaranteed to be multiple of 8. C_PPAUTO_8 is
unnecessary, removed.

Fixes #21992.

Change-Id: I75d5a0e5f5dc3dae335721fbec1bbcd4a3b862f2
Reviewed-on: https://go-review.googlesource.com/65730
Reviewed-by: David Chase <drchase@google.com>
2017-10-05 22:28:17 +00:00
Matthew Dempsky
f22ef70254 cmd/compile: allow := to shadow dot-imported names
Historically, gc optimistically parsed the left-hand side of
assignments as expressions. Later, if it discovered a ":=" assignment,
it rewrote the parsed expressions as declarations.

This failed in the presence of dot imports though, because we lost
information about whether an imported object was named via a bare
identifier "Foo" or a normal qualified "pkg.Foo".

This CL fixes the issue by specially noding the left-hand side of ":="
assignments.

Fixes #22076.

Change-Id: I18190ecdb863112e7d009e1687e6112eec559921
Reviewed-on: https://go-review.googlesource.com/66810
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>
Reviewed-by: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-10-05 18:07:37 +00:00
Keith Randall
41eabc0fc7 cmd/compile: fix merge rules for panic calls
Use entire inlining call stack to decide whether two panic calls
can be merged. We used to merge panic calls when only the leaf
line numbers matched, but that leads to places higher up the call
stack being merged incorrectly.

Fixes #22083

Change-Id: Ia41400a80de4b6ecf3e5089abce0c42b65e9b38a
Reviewed-on: https://go-review.googlesource.com/67632
Run-TryBot: Emmanuel Odeke <emm.odeke@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
2017-10-03 09:27:37 +00:00
Daniel Martí
39e523792e cmd/compile: fix another invalid switch case panic
Very similar fix to the one made in golang.org/cl/65655. This time it's
for switches on interface values, as we look for duplicates in a
different manner to keep types in mind.

As before, add a small regression test.

Updates #22001.
Fixes #22063.

Change-Id: I9a55d08999aeca262ad276b4649b51848a627b02
Reviewed-on: https://go-review.googlesource.com/66450
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2017-09-27 21:19:06 +00:00
Keith Randall
3f04db41a8 cmd/compile: fix sign-extension merging rules
If we have

  y = <int16> (MOVBQSX x)
  z = <int32> (MOVWQSX y)

We used to use this rewrite rule:

(MOVWQSX x:(MOVBQSX _)) -> x

But that resulted in replacing z with a value whose type
is only int16.  Then if z is spilled and restored, it gets
zero extended instead of sign extended.

Instead use the rule

(MOVWQSX (MOVBQSX x)) -> (MOVBQSX x)

The result is has the correct type, so it can be spilled
and restored correctly.  It might mean that a few more extension
ops might not be eliminated, but that's the price for correctness.

Fixes #21963

Change-Id: I6ec82c3d2dbe43cc1fee6fb2bd6b3a72fca3af00
Reviewed-on: https://go-review.googlesource.com/65290
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-09-26 16:24:08 +00:00
Anfernee Yongkun Gui
4cff104771 cmd/compile: fix print/println when input is uint
Fixes #21887

Change-Id: I30e8e03ecfb67a2c4deedc2c8436da4c4782136d
Reviewed-on: https://go-review.googlesource.com/63971
Run-TryBot: Emmanuel Odeke <emm.odeke@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
2017-09-26 04:08:38 +00:00
Daniel Martí
24ca86f308 cmd/compile: fix invalid switch case value panic
This is a regression introduced by myself in golang.org/cl/41852,
confirmed by the program that reproduces the crash that can be seen in
the added test.

Fixes #21988.

Change-Id: I18d5b2b3de63ced84db705b18490b00b16b59e02
Reviewed-on: https://go-review.googlesource.com/65655
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2017-09-24 10:15:52 +00:00
Austin Clements
e97209515a runtime: hide <autogenerated> methods from call stack
The compiler generates wrapper methods to forward interface method
calls (which are always pointer-based) to value methods. These
wrappers appear in the call stack even though they are an
implementation detail. This leaves ugly "<autogenerated>" functions in
stack traces and can throw off skip counts for stack traces.

Fix this by considering these runtime frames in printed stack traces
so they will only be printed if runtime frames are being printed, and
by eliding them from the call stack expansion used by CallersFrames
and Caller.

This removes the test for issue 4388 since that was checking that
"<autogenerated>" appeared in the stack trace instead of something
even weirder. We replace it with various runtime package tests.

Fixes #16723.

Change-Id: Ice3f118c66f254bb71478a664d62ab3fc7125819
Reviewed-on: https://go-review.googlesource.com/45412
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-09-22 22:17:20 +00:00
Matthew Dempsky
39983cf491 cmd/compile: refactor onebitwalktype1
The existing logic tried to advance the offset for each variable's
width, but then tried to undo this logic with the array and struct
handling code. It can all be much simpler by only worrying about
computing offsets within the array and struct code.

While here, include a short-circuit for zero-width arrays to fix a
pedantic compiler failure case.

Passes toolstash-check.

Fixes #20739.

Change-Id: I98af9bb512a33e3efe82b8bf1803199edb480640
Reviewed-on: https://go-review.googlesource.com/64471
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
2017-09-20 18:11:52 +00:00
Matthew Dempsky
7c8a9615c0 cmd/compile: fix stack frame info for calls in receiver slot
Previously, after inlining a call, we made a second pass to rewrite
the AST's position information to record the inlined stack frame. The
call arguments were part of this AST, but it would be incorrect to
rewrite them too, so extra effort was made to temporarily remove them
while the position rewriting was done.

However, this extra logic was only done for regular arguments: it was
not done for receiver arguments. Consequently if m was inlined in
"f().m(g(), h())", g and h would have correct call frames, but f would
appear to be called by m.

The fix taken by this CL is to merge setpos into inlsubst and only
rewrite position information for nodes that were actually copied from
the original function AST body. As a side benefit, this eliminates an
extra AST pass and some AST walking code.

Fixes #21879.

Change-Id: I22b25c208313fc25c358d3a2eebfc9b012400084
Reviewed-on: https://go-review.googlesource.com/64470
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
2017-09-19 18:35:24 +00:00
Matthew Dempsky
4347baac7d cmd/compile: eliminate OXFALL
Previously, we used OXFALL vs OFALL to distinguish fallthrough
statements that had been validated. Because in the Node AST we flatten
statement blocks, OXCASE and OXFALL needed to keep track of their
block scopes for this purpose.

Now that we have an AST that keeps these separate, we can just perform
the validation earlier.

Passes toolstash-check.

Fixes #14540.

Change-Id: I8421eaba16c2b3b72c9c5483b5cf20b14261385e
Reviewed-on: https://go-review.googlesource.com/61130
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
2017-09-19 18:08:50 +00:00
Matthew Dempsky
bb2f0da23a cmd/compile: fix compiler crash on recursive types
By setting both a valid size and alignment for broken recursive types,
we can appease some more safety checks and prevent compiler crashes.

Fixes #21882.

Change-Id: Ibaa137d8aa2c2a9d521462f144d7016c4abfd6e7
Reviewed-on: https://go-review.googlesource.com/64430
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
2017-09-18 21:49:43 +00:00
Kunpei Sakai
5a986eca86 all: fix article typos
a -> an

Change-Id: I7362bdc199e83073a712be657f5d9ba16df3077e
Reviewed-on: https://go-review.googlesource.com/63850
Reviewed-by: Rob Pike <r@golang.org>
2017-09-15 02:39:16 +00:00
Martin Möhrmann
137e4a6c63 cmd/compile: improve single blank variable handling in walkrange
Refactor walkrange to treat "for _ = range a" as "for range a".

This avoids generating some later discarded nodes in the compiler.

Passes toolstash -cmp.

Change-Id: Ifb2e1ca3b8519cbb67e8ad5aad514af9d18f1ec4
Reviewed-on: https://go-review.googlesource.com/61017
Run-TryBot: Martin Möhrmann <moehrmann@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2017-09-12 05:50:54 +00:00
Ian Lance Taylor
c6d019aa63 test: add test case that gccgo crashed on
Change-Id: I4d5d40e1ed3f58b2cdecd6248cb25c8ae9a1b9a1
Reviewed-on: https://go-review.googlesource.com/62531
Reviewed-by: David Crawshaw <crawshaw@golang.org>
2017-09-11 06:03:39 +00:00
Than McIntosh
08347648a6 test: add test that caused gccgo incorrect compilation
Updates #21770

Change-Id: Ic31c3bdae30797f406f25c737b83bbe2de1ed1da
Reviewed-on: https://go-review.googlesource.com/62331
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-09-09 13:32:23 +00:00
Keith Randall
02deb77f6d cmd/compile: fix println()
println with no arguments accidentally doesn't print a newline.

Introduced at CL 55097

Fixes #21808

Change-Id: I9fc7b4271b9b31e4c9b6078f055195dc3907b62c
Reviewed-on: https://go-review.googlesource.com/62390
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: Emmanuel Odeke <emm.odeke@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-09-08 20:10:48 +00:00
Matthew Dempsky
34db5f0c4d cmd/compile: fix evaluation order for OASOP
Currently, we handle "x op= y" by rewriting as "x = x op y", while
ensuring that any calls or receive operations in 'x' are only
evaluated once. Notably, pointer indirection, indexing operations,
etc. are left alone as it's typically safe to re-evaluate those.

However, those operations were interleaved with evaluating 'y', which
could include function calls that might cause re-evaluation to yield
different memory addresses.

As a fix, simply ensure that we order side-effecting operations in 'y'
before either evaluation of 'x'.

Fixes #21687.

Change-Id: Ib14e77760fda9c828e394e8e362dc9e5319a84b2
Reviewed-on: https://go-review.googlesource.com/60091
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
2017-09-05 18:10:17 +00:00
Cholerae Hu
fb165eaffd cmd/compile: combine x*n - y*n into (x-y)*n
Do the similar thing to CL 55143 to reduce IMUL.

Change-Id: I1bd38f618058e3cd74fac181f003610ea13f2294
Reviewed-on: https://go-review.googlesource.com/56252
Run-TryBot: Emmanuel Odeke <emm.odeke@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2017-09-03 14:29:38 +00:00
Keith Randall
053840dc00 cmd/compile: avoid generating large offsets
The assembler barfs on large offsets. Make sure that all the
instructions that need to have their offsets in an int32
  1) check on any rule that computes offsets for such instructions
  2) change their aux fields so the check builder checks it.

The assembler also silently misassembled offsets between 1<<31
and 1<<32. Add a check in the assembler to barf on those as well.

Fixes #21655

Change-Id: Iebf24bf10f9f37b3ea819ceb7d588251c0f46d7d
Reviewed-on: https://go-review.googlesource.com/59630
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
2017-08-28 22:02:59 +00:00
Keith Randall
f1517ec6e5 cmd/compile: remove more nil ptr checks after newobject
For code like the following (where x escapes):

   x := []int{1}

We're currently generating a nil check.  The line above is really 3 operations:

	t := new([1]int)
	t[0] = 1
	x := t[:]

We remove the nil check for t[0] = 1, but not for t[:].

Our current nil check removal rule is too strict about the possible
memory arguments of the nil check. Unlike zeroing or storing to the
result of runtime.newobject, the nilness of runtime.newobject is
always false, even after other stores have happened in the meantime.

Change-Id: I95fad4e3a59c27effdb37c43ea215e18f30b1e5f
Reviewed-on: https://go-review.googlesource.com/58711
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2017-08-25 03:26:58 +00:00
Michael Munday
744ebfde04 cmd/compile: eliminate stores to unread auto variables
This is a crude compiler pass to eliminate stores to auto variables
that are only ever written to.

Eliminates an unnecessary store to x from the following code:

func f() int {
	var x := 1
	return *(&x)
}

Fixes #19765.

Change-Id: If2c63a8ae67b8c590b6e0cc98a9610939a3eeffa
Reviewed-on: https://go-review.googlesource.com/38746
Run-TryBot: Michael Munday <mike.munday@ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2017-08-24 16:53:56 +00:00
Martin Möhrmann
cbc4e5d9c4 cmd/compile: generate makemap calls with int arguments
Where possible generate calls to runtime makemap with int hint argument
during compile time instead of makemap with int64 hint argument.

This eliminates converting the hint argument for calls to makemap with
int64 hint argument for platforms where int64 values do not fit into
an argument of type int.

A similar optimization for makeslice was introduced in CL
golang.org/cl/27851.

386:
name         old time/op    new time/op    delta
NewEmptyMap    53.5ns ± 5%    41.9ns ± 5%  -21.56%  (p=0.000 n=10+10)
NewSmallMap     182ns ± 1%     165ns ± 1%   -8.92%  (p=0.000 n=10+10)

Change-Id: Ibd2b4c57b36f171b173bf7a0602b3a59771e6e44
Reviewed-on: https://go-review.googlesource.com/55142
Reviewed-by: Keith Randall <khr@golang.org>
2017-08-22 20:28:21 +00:00
Kashav Madan
d05a1238d6 cmd/compile: avoid duplicate cast error
If an error was already printed during LHS conversion step, we don't reprint
the "cannot convert" error.

In particular, this prevents `_ = int("1")` (and all similar casts) from
resulting in multiple identical error messages being printed.

Fixes #20812.

Change-Id: If6e52c59eab438599d641ecf6f110ebafca740a9
Reviewed-on: https://go-review.googlesource.com/46912
Reviewed-by: Robert Griesemer <gri@golang.org>
2017-08-22 13:44:35 +00:00
Ian Lance Taylor
6711fa70ce test: add test that caused gccgo compiler crash
Updates #21253

Change-Id: Iece71a27207b578618cafb378dac2362517363d0
Reviewed-on: https://go-review.googlesource.com/52531
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Than McIntosh <thanm@google.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2017-08-17 18:09:52 +00:00
Alberto Donizetti
a0453a180f cmd/compile: combine x*n + y*n into (x+y)*n
There are a few cases where this can be useful. Apart from the obvious
(and silly)

  100*n + 200*n

where we generate one IMUL instead of two, consider:

  15*n + 31*n

Currently, the compiler strength-reduces both imuls, generating:

    0x0000 00000	MOVQ	"".n+8(SP), AX
	0x0005 00005 	MOVQ	AX, CX
	0x0008 00008 	SHLQ	$4, AX
	0x000c 00012 	SUBQ	CX, AX
	0x000f 00015 	MOVQ	CX, DX
	0x0012 00018 	SHLQ	$5, CX
	0x0016 00022 	SUBQ	DX, CX
	0x0019 00025 	ADDQ	CX, AX
	0x001c 00028 	MOVQ	AX, "".~r1+16(SP)
	0x0021 00033 	RET

But combining the imuls is both faster and shorter:

	0x0000 00000	MOVQ	"".n+8(SP), AX
	0x0005 00005 	IMULQ	$46, AX
	0x0009 00009	MOVQ	AX, "".~r1+16(SP)
	0x000e 00014 	RET

even without strength-reduction.

Moreover, consider:

  5*n + 7*(n+1) + 11*(n+2)

We already have a rule that rewrites 7(n+1) into 7n+7, so the
generated code (without imuls merging) looks like this:

	0x0000 00000 	MOVQ	"".n+8(SP), AX
	0x0005 00005 	LEAQ	(AX)(AX*4), CX
	0x0009 00009 	MOVQ	AX, DX
	0x000c 00012 	NEGQ	AX
	0x000f 00015 	LEAQ	(AX)(DX*8), AX
	0x0013 00019 	ADDQ	CX, AX
	0x0016 00022 	LEAQ	(DX)(CX*2), CX
	0x001a 00026 	LEAQ	29(AX)(CX*1), AX
	0x001f 00031 	MOVQ	AX, "".~r1+16(SP)

But with imuls merging, the 5n, 7n and 11n factors get merged, and the
generated code looks like this:

	0x0000 00000 	MOVQ	"".n+8(SP), AX
	0x0005 00005 	IMULQ	$23, AX
	0x0009 00009 	ADDQ	$29, AX
	0x000d 00013 	MOVQ	AX, "".~r1+16(SP)
	0x0012 00018 	RET

Which is both faster and shorter; that's also the exact same code that
clang and the intel c compiler generate for the above expression.

Change-Id: Ib4d5503f05d2f2efe31a1be14e2fe6cac33730a9
Reviewed-on: https://go-review.googlesource.com/55143
Reviewed-by: Keith Randall <khr@golang.org>
2017-08-16 16:51:59 +00:00
Martin Möhrmann
8a6e51aede cmd/compile: generate makechan calls with int arguments
Where possible generate calls to runtime makechan with int arguments
during compile time instead of makechan with int64 arguments.

This eliminates converting arguments for calls to makechan with
int64 arguments for platforms where int64 values do not fit into
arguments of type int.

A similar optimization for makeslice was introduced in CL
golang.org/cl/27851.

386:
name                old time/op  new time/op  delta
MakeChan/Byte       52.4ns ± 6%  45.0ns ± 1%  -14.14%  (p=0.000 n=10+10)
MakeChan/Int        54.5ns ± 1%  49.1ns ± 1%   -9.87%  (p=0.000 n=10+10)
MakeChan/Ptr         150ns ± 1%   143ns ± 0%   -4.38%  (p=0.000 n=9+7)
MakeChan/Struct/0   49.2ns ± 2%  43.2ns ± 2%  -12.27%  (p=0.000 n=10+10)
MakeChan/Struct/32  81.7ns ± 2%  76.2ns ± 1%   -6.71%  (p=0.000 n=10+10)
MakeChan/Struct/40  88.4ns ± 2%  82.5ns ± 2%   -6.60%  (p=0.000 n=10+10)

AMD64:
name                old time/op  new time/op  delta
MakeChan/Byte       83.4ns ± 8%  80.8ns ± 3%    ~     (p=0.171 n=10+10)
MakeChan/Int         101ns ± 3%   101ns ± 2%    ~     (p=0.412 n=10+10)
MakeChan/Ptr         128ns ± 1%   128ns ± 1%    ~     (p=0.191 n=10+10)
MakeChan/Struct/0   67.6ns ± 3%  68.7ns ± 4%    ~     (p=0.224 n=10+10)
MakeChan/Struct/32   138ns ± 1%   139ns ± 1%    ~     (p=0.185 n=10+9)
MakeChan/Struct/40   154ns ± 1%   154ns ± 1%  -0.55%  (p=0.027 n=10+9)

Change-Id: Ie854cb066007232c5e9f71ea7d6fe27e81a9c050
Reviewed-on: https://go-review.googlesource.com/55140
Run-TryBot: Martin Möhrmann <moehrmann@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2017-08-15 05:54:24 +00:00
Tobias Klauser
98031d8cd0 test: reenable ... test
The gofmt bug in question seems to be fixed (at least gofmt doesn't
complain), so reenable the commented-out ... test.

Change-Id: Icbfe0511160210557894ec8eb9b206aa6133d486
Reviewed-on: https://go-review.googlesource.com/55030
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-08-11 17:41:17 +00:00
Tobias Klauser
d7ec89c198 test: add missing escape analysis test
https://golang.org/cl/37508 added an escape analysis test for #12397 to
escape2.go but missed to add it to escape2n.go. The comment at the top
of the former states that the latter should contain all the same tests
and the tests only differ in using -N to compile. Conform to this by
adding the function issue12397 to escape2n.go as well.

Also fix a whitespace difference in escape2.go, so the two files match
exactly (except for the comment at the top).

Change-Id: I3a09cf95169bf2150a25d6b4ec9e147265d36760
Reviewed-on: https://go-review.googlesource.com/54610
Reviewed-by: Avelino <t@avelino.xxx>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
2017-08-11 00:56:21 +00:00
Josh Bleecher Snyder
e157fac02d test: add README
Updates #21034

Change-Id: I951fb48ab3b9ed54d225c11879db8f09048a36a3
Reviewed-on: https://go-review.googlesource.com/50950
Reviewed-by: Rob Pike <r@golang.org>
2017-07-26 23:37:25 +00:00
Ian Lance Taylor
ee392ac10c cmd/compile: consider exported flag in namedata
It is possible to have an unexported name with a nil package,
for an embedded field whose type is a pointer to an unexported type.
We must encode that fact in the type..namedata symbol name,
to avoid incorrectly merging an unexported name with an exported name.

Fixes #21120

Change-Id: I2e3879d77fa15c05ad92e0bf8e55f74082db5111
Reviewed-on: https://go-review.googlesource.com/50710
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
2017-07-24 18:05:00 +00:00
Michael Munday
93b7eb973f cmd/compile: fix unaligned loads/stores to global variables on s390x
Load/store-merging and move optimizations can result in unaligned
memory accesses. This is fine so long as the load/store instruction
used does not take a relative offset. In the SSA rules this means we
must not merge (MOVDaddr (SB)) ops into loads/stores unless we can
guarantee the alignment of the target.

Fixes #21048.

Change-Id: I70f13a62a148d5f0a56e704e8f76e36b4a4226d9
Reviewed-on: https://go-review.googlesource.com/49250
Run-TryBot: Michael Munday <mike.munday@ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2017-07-19 14:22:48 +00:00
Russ Cox
f0cf740733 cmd/compile: omit X:framepointer in compile version
Framepointer is the default now. Only print an X: list
if the settings are _not_ the default.

Before:

$ go tool compile -V
compile version devel +a5f30d9508 Sun Jul 16 14:43:48 2017 -0400 X:framepointer
$ go1.8 tool compile -V
compile version go1.8 X:framepointer
$

After:

$ go tool compile -V
compile version devel +a5f30d9508 Sun Jul 16 14:43:48 2017 -0400
$ go1.9 tool compile -V # imagined
compile version go1.9
$

Perpetuates #18317.

Change-Id: I981ba5c62be32e650a166fc9740703122595639b
Reviewed-on: https://go-review.googlesource.com/49252
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2017-07-17 16:36:49 +00:00
Josh Bleecher Snyder
a1e7fb4eed test: deflake chan/select3.go
On a slow or distracted machine, 0.1s is sometimes
not long enough for a non-blocking function call to complete.
This causes rare test flakes.
They can be easily reproduced by reducing the wait time to (say) 100ns.

For non-blocking functions, increase the window from 100ms to 10s.
Using different windows for block and non-blocking functions,
allows us to reduce the time for blocking functions.
The risk here is false negatives, but that risk is low;
this test is run repeatedly on many fast machines,
for which 10ms is ample time.
This reduces the time required to run the test by a factor of 10,
from ~1s to ~100ms.

Fixes #20299

Change-Id: Ice9a641a66c6c101d738a2ebe1bcb144ae3c9916
Reviewed-on: https://go-review.googlesource.com/47812
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-07-08 02:10:12 +00:00
Cherry Zhang
c920fa537f cmd/compile: fix slice-in-bound check on amd64p32
Should use CMPL instead of CMPQ.

Fixes #20811.

Change-Id: I610d487949c2c8a08b3743656149069d931a51bb
Reviewed-on: https://go-review.googlesource.com/46870
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-06-28 16:20:53 +00:00
Matthew Dempsky
f62c608abb cmd/compile: suppress errors after "cannot assign to X"
If the LHS is unassignable, there's no point in trying to make sure
the RHS can be assigned to it or making sure they're realizable
types. This is consistent with go/types.

In particular, this prevents "1 = 2" from causing a panic when "1"
still ends up with the type "untyped int", which is not realizable.

Fixes #20813.

Change-Id: I4710bdaac2e375ef12ec29b888b8ac84fb640e56
Reviewed-on: https://go-review.googlesource.com/46835
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
2017-06-27 20:29:33 +00:00
Gabríel Arthúr Pétursson
09899d9b91 test/fixedbugs: Close opening parenthesis in comment in issue20789.go
Updates #20789

Change-Id: Ic7a94394e283bc1b667cdad999ceee9513f35e37
Reviewed-on: https://go-review.googlesource.com/46770
Reviewed-by: Robert Griesemer <gri@golang.org>
2017-06-27 00:01:20 +00:00
Robert Griesemer
6d594342c6 cmd/compile: use correct variable when setting up dummy CallStmt in error
Fixes crash when printing a related error message later on.

Fixes #20789.

Change-Id: I6d2c35aafcaeda26a211fc6c8b7dfe4a095a3efe
Reviewed-on: https://go-review.googlesource.com/46713
Run-TryBot: Robert Griesemer <gri@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-06-26 18:39:37 +00:00
Robert Griesemer
47e659b01f cmd/compile: fix array slice expression bounds check
Fixes #20749.

Change-Id: Ic6a7edc858575c4cb8b2e2ca97ee0c4b69f22c27
Reviewed-on: https://go-review.googlesource.com/46466
Run-TryBot: Robert Griesemer <gri@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-06-22 23:31:45 +00:00
David Chase
0b6fbaae6e cmd/compile: make loop guard+rotate conditional on GOEXPERIMENT
Loops of the form "for i,e := range" needed to have their
condition rotated to the "bottom" for the preemptible loops
GOEXPERIMENT, but this caused a performance regression
because it degraded bounds check removal.  For now, make
the loop rotation/guarding conditional on the experiment.

Fixes #20711.
Updates #10958.

Change-Id: Icfba14cb3b13a910c349df8f84838cf4d9d20cf6
Reviewed-on: https://go-review.googlesource.com/46410
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2017-06-21 22:07:33 +00:00
Matthew Dempsky
6e549d2dfd cmd/compile: add regress test for #20682
Minimal reconstruction of reported failure case.

Manually verified that test fails with CL 45911 reverted.

Change-Id: Ia5d11500d91b46ba1eb5d841db3987edb9136c39
Reviewed-on: https://go-review.googlesource.com/45970
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Robert Griesemer <gri@golang.org>
2017-06-15 22:01:35 +00:00
Matthew Dempsky
ff0748670c cmd/compile: fix exporting of function bodies
Before CL 36170, we identified all function bodies that needed to be
exported before writing any export data.

With CL 36170, we started identifying additional functions while
exporting function bodies. As a consequence, we cannot use a
range-based for loop for iterating over function bodies anymore.

Fixes #18895.

Change-Id: I9cbefa8d311ca8c9898c8272b2ac365976b02396
Reviewed-on: https://go-review.googlesource.com/45817
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
2017-06-15 04:17:30 +00:00
Keith Randall
79d05e75ca runtime: restore arm assembly stubs for div/mod
These are used by DIV[U] and MOD[U] assembly instructions.
Add a test in the stdlib so we actually exercise linking
to these routines.

Update #19507

Change-Id: I0d8e19a53e3744abc0c661ea95486f94ec67585e
Reviewed-on: https://go-review.googlesource.com/45703
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2017-06-15 03:51:03 +00:00
Robert Griesemer
cabf622da8 cmd/compile: fix detection of calls to reflect.Method
The existing code used Type.String() to obtain the name of a type;
specifically type reflect.Method in this case. However, Type.String()
formatting is intended for error messages and uses the format
pkgpath.name instead of pkgname.name if a package (in this case
package reflect) is imported multiple times. As a result, the
reflect.Method type detection failed under peculiar circumstances
(see the included test case).

Thanks to https://github.com/ericlagergren for tracking down
an easy way to make the bug disappear (which in turn directly
led to the underlying cause).

Fixes #19028.

Change-Id: I1b9c5dfd183260a9be74969fe916a94146fc36da
Reviewed-on: https://go-review.googlesource.com/45777
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2017-06-14 21:57:56 +00:00