1. 09 May, 2017 14 commits
    • Josh Bleecher Snyder's avatar
      cmd/compile: make builds reproducible in presence of **byte and **int8 · 6f2ee0f3
      Josh Bleecher Snyder authored
      CL 39915 introduced sorting of signats by ShortString
      for reproducible builds. But ShortString treats types
      byte and uint8 identically; same for rune and uint32.
      CL 39915 attempted to compensate for this by only
      adding the underlying type (uint8) to signats in addsignat.
      
      This only works for byte and uint8. For e.g. *byte and *uint,
      both get added, and their sort order is random,
      leading to non-reproducible builds.
      
      One fix would be to add yet another type printing mode
      that doesn't eliminate byte and rune, and use it
      for sorting signats. But the formatting routines
      are complicated enough as it is.
      
      Instead, just sort first by ShortString and then by String.
      We can't just use String, because ShortString makes distinctions
      that String doesn't. ShortString is really preferred here;
      String is serving only as a backstop for handling of bytes and runes.
      
      The long series of types in the test helps increase the odds of
      failure, allowing a smaller number of iterations in the test.
      On my machine, a full test takes 700ms.
      
      Passes toolstash-check.
      
      Updates #19961
      Fixes #20272
      
      name        old alloc/op      new alloc/op      delta
      Template         37.9MB ± 0%       37.9MB ± 0%  +0.12%  (p=0.032 n=5+5)
      Unicode          28.9MB ± 0%       28.9MB ± 0%    ~     (p=0.841 n=5+5)
      GoTypes           110MB ± 0%        110MB ± 0%    ~     (p=0.841 n=5+5)
      Compiler          463MB ± 0%        463MB ± 0%    ~     (p=0.056 n=5+5)
      SSA              1.11GB ± 0%       1.11GB ± 0%  +0.02%  (p=0.016 n=5+5)
      Flate            24.7MB ± 0%       24.8MB ± 0%  +0.14%  (p=0.032 n=5+5)
      GoParser         31.1MB ± 0%       31.1MB ± 0%    ~     (p=0.421 n=5+5)
      Reflect          73.9MB ± 0%       73.9MB ± 0%    ~     (p=1.000 n=5+5)
      Tar              25.8MB ± 0%       25.8MB ± 0%  +0.15%  (p=0.016 n=5+5)
      XML              41.2MB ± 0%       41.2MB ± 0%    ~     (p=0.310 n=5+5)
      [Geo mean]       72.0MB            72.0MB       +0.07%
      
      name        old allocs/op     new allocs/op     delta
      Template           384k ± 0%         385k ± 1%    ~     (p=0.056 n=5+5)
      Unicode            343k ± 0%         344k ± 0%    ~     (p=0.548 n=5+5)
      GoTypes           1.16M ± 0%        1.16M ± 0%    ~     (p=0.421 n=5+5)
      Compiler          4.43M ± 0%        4.44M ± 0%  +0.26%  (p=0.032 n=5+5)
      SSA               9.86M ± 0%        9.87M ± 0%  +0.10%  (p=0.032 n=5+5)
      Flate              237k ± 1%         238k ± 0%  +0.49%  (p=0.032 n=5+5)
      GoParser           319k ± 1%         320k ± 1%    ~     (p=0.151 n=5+5)
      Reflect            957k ± 0%         957k ± 0%    ~     (p=1.000 n=5+5)
      Tar                251k ± 0%         252k ± 1%  +0.49%  (p=0.016 n=5+5)
      XML                399k ± 0%         401k ± 1%    ~     (p=0.310 n=5+5)
      [Geo mean]         739k              741k       +0.26%
      
      Change-Id: Ic27995a8d374d012b8aca14546b1df9d28d30df7
      Reviewed-on: https://go-review.googlesource.com/42955
      Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
      TryBot-Result: Gobot Gobot <gobot@golang.org>
      Reviewed-by: 's avatarRobert Griesemer <gri@golang.org>
      6f2ee0f3
    • Josh Bleecher Snyder's avatar
      cmd/compile: make "imported and not used" errors deterministic · 9fda4df9
      Josh Bleecher Snyder authored
      If there were more unused imports than
      the maximum default number of errors to report,
      the set of reported imports was non-deterministic.
      
      Fix by accumulating and sorting them prior to output.
      
      Fixes #20298
      
      Change-Id: Ib3d5a15fd7dc40009523fcdc1b93ddc62a1b05f2
      Reviewed-on: https://go-review.googlesource.com/42954
      Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
      TryBot-Result: Gobot Gobot <gobot@golang.org>
      Reviewed-by: 's avatarRobert Griesemer <gri@golang.org>
      9fda4df9
    • Cherry Zhang's avatar
      cmd/internal/obj/arm64, cmd/compile: improve offset folding on ARM64 · fb0ccc5d
      Cherry Zhang authored
      ARM64 assembler backend only accepts loads and stores with small
      or aligned offset. The compiler therefore can only fold small or
      aligned offsets into loads and stores. For locals and args, their
      offsets to SP are not known until very late, and the compiler
      makes conservative decision not folding some of them. However,
      in most cases, the offset is indeed small or aligned, and can
      be folded into load and store (but actually not).
      
      This CL adds support of loads and stores with large and unaligned
      offsets. When the offset doesn't fit into the instruction, it
      uses two instructions and (for very large offset) the constant
      pool. This way, the compiler doesn't need to be conservative,
      and can simply fold the offset.
      
      To make it work, the assembler's optab matching rules need to be
      changed. Before, MOVD accepts C_UAUTO32K which matches multiple
      of 8 between 0 and 32K, and also C_UAUTO16K, which may not be
      multiple of 8 and does not fit into MOVD instruction. The
      assembler errors in the latter case. This change makes it only
      matches multiple of 8 (or offsets within ±256, which also fits
      in instruction), and uses the large-or-unaligned-offset rule
      for things doesn't fit (without error). Other sized move rules
      are changed similarly.
      
      Class C_UAUTO64K and C_UOREG64K are removed, as they are never
      used.
      
      In shared library, load/store of global is rewritten to using
      GOT and temp register, which conflicts with the use of temp
      register for assembling large offset. So the folding is disabled
      for globals in shared library mode.
      
      Reduce cmd/go binary size by 2%.
      
      name                     old time/op    new time/op    delta
      BinaryTree17-8              8.67s ± 0%     8.61s ± 0%   -0.60%  (p=0.000 n=9+10)
      Fannkuch11-8                6.24s ± 0%     6.19s ± 0%   -0.83%  (p=0.000 n=10+9)
      FmtFprintfEmpty-8           116ns ± 0%     116ns ± 0%     ~     (all equal)
      FmtFprintfString-8          196ns ± 0%     192ns ± 0%   -1.89%  (p=0.000 n=10+10)
      FmtFprintfInt-8             199ns ± 0%     198ns ± 0%   -0.35%  (p=0.001 n=9+10)
      FmtFprintfIntInt-8          294ns ± 0%     293ns ± 0%   -0.34%  (p=0.000 n=8+8)
      FmtFprintfPrefixedInt-8     318ns ± 1%     318ns ± 1%     ~     (p=1.000 n=10+10)
      FmtFprintfFloat-8           537ns ± 0%     531ns ± 0%   -1.17%  (p=0.000 n=9+10)
      FmtManyArgs-8              1.19µs ± 1%    1.18µs ± 1%   -1.41%  (p=0.001 n=10+10)
      GobDecode-8                17.2ms ± 1%    17.3ms ± 2%     ~     (p=0.165 n=10+10)
      GobEncode-8                14.7ms ± 1%    14.7ms ± 2%     ~     (p=0.631 n=10+10)
      Gzip-8                      837ms ± 0%     836ms ± 0%   -0.14%  (p=0.006 n=9+10)
      Gunzip-8                    141ms ± 0%     139ms ± 0%   -1.24%  (p=0.000 n=9+10)
      HTTPClientServer-8          256µs ± 1%     253µs ± 1%   -1.35%  (p=0.000 n=10+10)
      JSONEncode-8               40.1ms ± 1%    41.3ms ± 1%   +3.06%  (p=0.000 n=10+9)
      JSONDecode-8                157ms ± 1%     156ms ± 1%   -0.83%  (p=0.001 n=9+8)
      Mandelbrot200-8            8.94ms ± 0%    8.94ms ± 0%   +0.02%  (p=0.000 n=9+9)
      GoParse-8                  8.69ms ± 0%    8.54ms ± 1%   -1.69%  (p=0.000 n=8+10)
      RegexpMatchEasy0_32-8       227ns ± 1%     228ns ± 1%   +0.48%  (p=0.016 n=10+9)
      RegexpMatchEasy0_1K-8      1.92µs ± 0%    1.63µs ± 0%  -15.08%  (p=0.000 n=10+9)
      RegexpMatchEasy1_32-8       256ns ± 0%     251ns ± 0%   -2.19%  (p=0.000 n=10+9)
      RegexpMatchEasy1_1K-8      2.38µs ± 0%    2.09µs ± 0%  -12.49%  (p=0.000 n=10+9)
      RegexpMatchMedium_32-8      352ns ± 0%     354ns ± 0%   +0.39%  (p=0.002 n=10+9)
      RegexpMatchMedium_1K-8      106µs ± 0%     106µs ± 0%   -0.05%  (p=0.005 n=10+9)
      RegexpMatchHard_32-8       5.92µs ± 0%    5.89µs ± 0%   -0.40%  (p=0.000 n=9+8)
      RegexpMatchHard_1K-8        180µs ± 0%     179µs ± 0%   -0.14%  (p=0.000 n=10+9)
      Revcomp-8                   1.20s ± 0%     1.13s ± 0%   -6.29%  (p=0.000 n=9+8)
      Template-8                  159ms ± 1%     154ms ± 1%   -3.14%  (p=0.000 n=9+10)
      TimeParse-8                 800ns ± 3%     769ns ± 1%   -3.91%  (p=0.000 n=10+10)
      TimeFormat-8                826ns ± 2%     817ns ± 2%   -1.04%  (p=0.050 n=10+10)
      [Geo mean]                  145µs          143µs        -1.79%
      
      Change-Id: I5fc42087cee9b54ea414f8ef6d6d020b80eb5985
      Reviewed-on: https://go-review.googlesource.com/42172
      Run-TryBot: Cherry Zhang <cherryyz@google.com>
      Reviewed-by: 's avatarDavid Chase <drchase@google.com>
      fb0ccc5d
    • Josh Bleecher Snyder's avatar
      cmd/go: enable concurrent backend compilation by default · 5e0bcb38
      Josh Bleecher Snyder authored
      It can be disabled by setting the environment variable
      GO19CONCURRENTCOMPILATION=0, or with -gcflags=-c=1.
      
      Fixes #15756.
      
      Change-Id: I7acbf16330512b62ee14ecbab1f46b53ec5a67b6
      Reviewed-on: https://go-review.googlesource.com/41820
      Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
      TryBot-Result: Gobot Gobot <gobot@golang.org>
      Reviewed-by: 's avatarKeith Randall <khr@golang.org>
      5e0bcb38
    • Josh Bleecher Snyder's avatar
      cmd/go: add support for concurrent backend compilation · f4e5bd48
      Josh Bleecher Snyder authored
      It is disabled by default.
      It can be enabled by setting the environment variable
      GO19CONCURRENTCOMPILATION=1.
      
      Benchmarking results are presented in a grid.
      Columns are different values of c (compiler backend concurrency);
      rows are different values of p (process concurrency).
      
      'go build -a std cmd', a 4 core raspberry pi 3:
      
                  c=1        c=2        c=4
      StdCmd/p=1  504s ± 2%  413s ± 4%  367s ± 3%
      StdCmd/p=2  314s ± 3%  266s ± 4%  267s ± 4%
      StdCmd/p=4  254s ± 5%  241s ± 5%  238s ± 6%
      
      'go build -a std cmd', an 8 core darwin/amd64 laptop:
      
                  c=1         c=2         c=4         c=6         c=8
      StdCmd/p=1  40.4s ± 7%  31.0s ± 1%  27.3s ± 1%  27.8s ± 0%  27.7s ± 0%
      StdCmd/p=2  21.9s ± 1%  17.9s ± 1%  16.9s ± 1%  17.0s ± 1%  17.2s ± 0%
      StdCmd/p=4  17.4s ± 2%  14.5s ± 2%  13.3s ± 2%  13.5s ± 2%  13.6s ± 2%
      StdCmd/p=6  16.9s ± 1%  14.2s ± 2%  13.1s ± 2%  13.2s ± 2%  13.3s ± 2%
      StdCmd/p=8  16.7s ± 2%  14.2s ± 2%  13.2s ± 3%  13.2s ± 2%  13.4s ± 2%
      
      'go build -a std cmd', a 96 core arm64 server:
      
                   c=1         c=2         c=4         c=6         c=8         c=16        c=32        c=64        c=96
      StdCmd/p=1    173s ± 1%   133s ± 1%   114s ± 1%   109s ± 1%   106s ± 0%   106s ± 1%   107s ± 1%   110s ± 1%   113s ± 1%
      StdCmd/p=2   94.2s ± 2%  71.5s ± 1%  61.7s ± 1%  58.7s ± 1%  57.5s ± 2%  56.9s ± 1%  58.0s ± 1%  59.6s ± 1%  61.0s ± 1%
      StdCmd/p=4   74.1s ± 2%  53.5s ± 1%  43.7s ± 2%  40.5s ± 1%  39.2s ± 2%  38.9s ± 2%  39.5s ± 3%  40.3s ± 2%  40.8s ± 1%
      StdCmd/p=6   69.3s ± 1%  50.2s ± 2%  40.3s ± 2%  37.3s ± 3%  36.0s ± 3%  35.3s ± 2%  36.0s ± 2%  36.8s ± 2%  37.5s ± 2%
      StdCmd/p=8   66.1s ± 2%  47.7s ± 2%  38.6s ± 2%  35.7s ± 2%  34.4s ± 1%  33.6s ± 2%  34.2s ± 2%  34.6s ± 1%  35.0s ± 1%
      StdCmd/p=16  63.4s ± 2%  45.3s ± 2%  36.3s ± 2%  33.3s ± 2%  32.0s ± 3%  31.6s ± 2%  32.1s ± 2%  32.5s ± 2%  32.7s ± 2%
      StdCmd/p=32  62.2s ± 1%  44.2s ± 2%  35.3s ± 2%  32.4s ± 2%  31.2s ± 2%  30.9s ± 2%  31.1s ± 2%  31.7s ± 2%  32.0s ± 2%
      StdCmd/p=64  62.2s ± 1%  44.3s ± 2%  35.4s ± 2%  32.4s ± 2%  31.2s ± 2%  30.9s ± 2%  31.2s ± 2%  31.8s ± 3%  32.2s ± 3%
      StdCmd/p=96  62.2s ± 2%  44.4s ± 2%  35.3s ± 2%  32.3s ± 2%  31.1s ± 2%  30.9s ± 3%  31.3s ± 2%  31.7s ± 1%  32.1s ± 2%
      
      benchjuju, an 8 core darwin/amd64 laptop:
      
                     c=1         c=2         c=4         c=6         c=8
      BuildJuju/p=1  55.3s ± 0%  46.3s ± 0%  41.9s ± 0%  41.4s ± 1%  41.3s ± 0%
      BuildJuju/p=2  33.7s ± 1%  28.4s ± 1%  26.7s ± 1%  26.6s ± 1%  26.8s ± 1%
      BuildJuju/p=4  24.7s ± 1%  22.3s ± 1%  21.4s ± 1%  21.7s ± 1%  21.8s ± 1%
      BuildJuju/p=6  20.6s ± 1%  19.3s ± 2%  19.4s ± 1%  19.7s ± 1%  19.9s ± 1%
      BuildJuju/p=8  20.6s ± 2%  19.5s ± 2%  19.3s ± 2%  19.6s ± 1%  19.8s ± 2%
      
      Updates #15756
      
      Change-Id: I8a56e88953071a05eee764002024c54cd888a56c
      Reviewed-on: https://go-review.googlesource.com/41819
      Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
      TryBot-Result: Gobot Gobot <gobot@golang.org>
      Reviewed-by: 's avatarBrad Fitzpatrick <bradfitz@golang.org>
      f4e5bd48
    • Robert Griesemer's avatar
      spec: clarify unsafe.Pointer conversions · 86f5f7fd
      Robert Griesemer authored
      A pointer type of underlying type unsafe.Pointer can be used in
      unsafe conversions. Document unfortunate status quo.
      
      Fixes #19306.
      
      Change-Id: I28172508a200561f8df366bbf2c2807ef3b48c97
      Reviewed-on: https://go-review.googlesource.com/42132Reviewed-by: 's avatarMatthew Dempsky <mdempsky@google.com>
      Reviewed-by: 's avatarRuss Cox <rsc@golang.org>
      Reviewed-by: 's avatarIan Lance Taylor <iant@golang.org>
      86f5f7fd
    • Ibrahim AshShohail's avatar
      go/token: remove excess parenthesis in NoPos.IsValid() documentation · 54102963
      Ibrahim AshShohail authored
      Fixes #20294
      
      Change-Id: I32ac862fe00180210a04103cc94c4d9fef5d1b6c
      Reviewed-on: https://go-review.googlesource.com/42992Reviewed-by: 's avatarBrad Fitzpatrick <bradfitz@golang.org>
      54102963
    • Austin Clements's avatar
      runtime/pprof: deflake TestGoroutineCounts · d659682d
      Austin Clements authored
      TestGoroutineCounts currently depends on timing to get 100 goroutines
      to a known blocking point before taking a profile. This fails
      frequently, with different goroutines captured at different stacks.
      The test is disabled on openbsd because it was too flaky, but in fact
      it flakes on all platforms.
      
      Fix this by using Gosched instead of timing. This is both much more
      reliable and makes the test run faster.
      
      Fixes #15156.
      
      Change-Id: Ia6e894196d717655b8fb4ee96df53f6cc8bc5f1f
      Reviewed-on: https://go-review.googlesource.com/42953
      Run-TryBot: Austin Clements <austin@google.com>
      TryBot-Result: Gobot Gobot <gobot@golang.org>
      Reviewed-by: 's avatarIan Lance Taylor <iant@golang.org>
      Reviewed-by: 's avatarBrad Fitzpatrick <bradfitz@golang.org>
      d659682d
    • Ian Lance Taylor's avatar
      cmd/go: put user flags after code generation flag · 9eacd977
      Ian Lance Taylor authored
      This permits the user to override the code generation flag when they
      know better. This is always a good policy for all flags automatically
      inserted by the build system.
      
      Doing this now so that I can write a test for #20290.
      
      Update #20290
      
      Change-Id: I5c6708a277238d571b8d037993a5a59e2a442e98
      Reviewed-on: https://go-review.googlesource.com/42952
      Run-TryBot: Ian Lance Taylor <iant@golang.org>
      Reviewed-by: 's avatarBrad Fitzpatrick <bradfitz@golang.org>
      TryBot-Result: Gobot Gobot <gobot@golang.org>
      9eacd977
    • Rob Phoenix's avatar
      net: fix ExampleParseCIDR IPv4 prefix length · 1e732ca3
      Rob Phoenix authored
      Issue #15228 describes that reserved address blocks should be used for
      documentation purposes. This change updates the prefix length so the
      IPv4 address adheres to this.
      
      Change-Id: I237d9cce1a71f4fd95f927ec894ce53fa806047f
      Reviewed-on: https://go-review.googlesource.com/42991
      Run-TryBot: Ian Lance Taylor <iant@golang.org>
      TryBot-Result: Gobot Gobot <gobot@golang.org>
      Reviewed-by: 's avatarBrad Fitzpatrick <bradfitz@golang.org>
      1e732ca3
    • Alex Brainman's avatar
      cmd/go: run tests that require symlinks · 096e2bff
      Alex Brainman authored
      Change-Id: I19a724ea4eb1ba0ff558721650c89a949e53b7c7
      Reviewed-on: https://go-review.googlesource.com/42895Reviewed-by: 's avatarBrad Fitzpatrick <bradfitz@golang.org>
      Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
      TryBot-Result: Gobot Gobot <gobot@golang.org>
      096e2bff
    • Alex Brainman's avatar
      os: avoid calulating fileStat.path until it is needed · 6dcaa095
      Alex Brainman authored
      This CL improves
      
      on my Windows 7
      
      name         old time/op    new time/op    delta
      Readdirname    58.1µs ± 1%    58.1µs ± 0%     ~     (p=0.817 n=8+8)
      Readdir        58.0µs ± 3%    57.8µs ± 0%     ~     (p=0.944 n=9+8)
      
      name         old alloc/op   new alloc/op   delta
      Readdirname    3.03kB ± 0%    2.84kB ± 0%   -6.33%  (p=0.000 n=10+10)
      Readdir        3.00kB ± 0%    2.81kB ± 0%   -6.40%  (p=0.000 n=10+10)
      
      name         old allocs/op  new allocs/op  delta
      Readdirname      34.0 ± 0%      30.0 ± 0%  -11.76%  (p=0.000 n=10+10)
      Readdir          33.0 ± 0%      29.0 ± 0%  -12.12%  (p=0.000 n=10+10)
      
      on my Windows XP
      
      name           old time/op    new time/op    delta
      Readdirname-2    85.5µs ± 0%    84.0µs ± 0%   -1.83%  (p=0.000 n=10+10)
      Readdir-2        84.6µs ± 0%    83.5µs ± 0%   -1.31%  (p=0.000 n=10+9)
      
      name           old alloc/op   new alloc/op   delta
      Readdirname-2    6.52kB ± 0%    5.66kB ± 0%  -13.25%  (p=0.000 n=10+10)
      Readdir-2        6.39kB ± 0%    5.53kB ± 0%  -13.52%  (p=0.000 n=10+10)
      
      name           old allocs/op  new allocs/op  delta
      Readdirname-2      78.0 ± 0%      66.0 ± 0%  -15.38%  (p=0.000 n=10+10)
      Readdir-2          77.0 ± 0%      65.0 ± 0%  -15.58%  (p=0.000 n=10+10)
      
      Change-Id: I5d698eca86b8e94a46b6cfbd5947898b7b3fbdbd
      Reviewed-on: https://go-review.googlesource.com/42894Reviewed-by: 's avatarBrad Fitzpatrick <bradfitz@golang.org>
      Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
      TryBot-Result: Gobot Gobot <gobot@golang.org>
      6dcaa095
    • ltnwgl's avatar
      container/heap: optimization when selecting smaller child · f5352a77
      ltnwgl authored
      In down(), if two children are equal, we can choose either one.
      Inspired by https://codereview.appspot.com/6613064/
      
      Change-Id: Iaad4ca5e2f5111bf3abb87f606584e7d274c620b
      Reviewed-on: https://go-review.googlesource.com/38612
      Run-TryBot: Robert Griesemer <gri@golang.org>
      Reviewed-by: 's avatarRobert Griesemer <gri@golang.org>
      f5352a77
    • Rob Phoenix's avatar
      net: add examples for IPv4, ParseCIDR & IPv4Mask · 716761b8
      Rob Phoenix authored
      Further examples to support the net package.
      
      See issue #5757
      
      Change-Id: I839fd97a468c8d9195e8f4a0ee886ba50ca3f382
      Reviewed-on: https://go-review.googlesource.com/42912Reviewed-by: 's avatarBrad Fitzpatrick <bradfitz@golang.org>
      Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
      TryBot-Result: Gobot Gobot <gobot@golang.org>
      716761b8
  2. 08 May, 2017 4 commits
    • Robert Griesemer's avatar
      cmd/compile: better errors for float constants with large exponents · bcf2d74c
      Robert Griesemer authored
      Also: Removed misleading comment.
      
      Fixes #20232.
      
      Change-Id: I0b141b1360ac53267b7ebfcec7a2e2a238f3f46c
      Reviewed-on: https://go-review.googlesource.com/42930
      Run-TryBot: Robert Griesemer <gri@golang.org>
      TryBot-Result: Gobot Gobot <gobot@golang.org>
      Reviewed-by: 's avatarMatthew Dempsky <mdempsky@google.com>
      bcf2d74c
    • Bill O'Farrell's avatar
      math: use SIMD to accelerate additional scalar math functions on s390x · 88672de7
      Bill O'Farrell authored
      As necessary, math functions were structured to use stubs, so that they can
      be accelerated with assembly on any platform.
      
      Technique used was minimax polynomial approximation using tables of
      polynomial coefficients, with argument range reduction.
      
      Benchmark         New     Old     Speedup
      BenchmarkAcos     12.2    47.5    3.89
      BenchmarkAcosh    18.5    56.2    3.04
      BenchmarkAsin     13.1    40.6    3.10
      BenchmarkAsinh    19.4    62.8    3.24
      BenchmarkAtan     10.1    23      2.28
      BenchmarkAtanh    19.1    53.2    2.79
      BenchmarkAtan2    16.5    33.9    2.05
      BenchmarkCbrt     14.8    58      3.92
      BenchmarkErf      10.8    20.1    1.86
      BenchmarkErfc     11.2    23.5    2.10
      BenchmarkExp      8.77    53.8    6.13
      BenchmarkExpm1    10.1    38.3    3.79
      BenchmarkLog      13.1    40.1    3.06
      BenchmarkLog1p    12.7    38.3    3.02
      BenchmarkPowInt   31.7    40.5    1.28
      BenchmarkPowFrac  33.1    141     4.26
      BenchmarkTan      11.5    30      2.61
      
      Accuracy was tested against a high precision
      reference function to determine maximum error.
      Note: ulperr is error in "units in the last place"
      
             max
            ulperr
      Acos  1.15
      Acosh 1.07
      Asin  2.22
      Asinh 1.72
      Atan  1.41
      Atanh 3.00
      Atan2 1.45
      Cbrt  1.18
      Erf   1.29
      Erfc  4.82
      Exp   1.00
      Expm1 2.26
      Log   0.94
      Log1p 2.39
      Tan   3.14
      
      Pow will have 99.99% correctly rounded results with reasonable inputs
      producing numeric (non Inf or NaN) results
      
      Change-Id: I850e8cf7b70426e8b54ec49d74acd4cddc8c6cb2
      Reviewed-on: https://go-review.googlesource.com/38585Reviewed-by: 's avatarMichael Munday <munday@ca.ibm.com>
      Run-TryBot: Michael Munday <munday@ca.ibm.com>
      TryBot-Result: Gobot Gobot <gobot@golang.org>
      88672de7
    • Marvin Stenger's avatar
      bytes: skip inline test by default · 8c49c06b
      Marvin Stenger authored
      The test "TestTryGrowByResliceInlined" introduced in c08ac367 broke the
      noopt builder as it fails when inlining is disabled.
      Since there are currently no other options at hand for checking
      inlined-ness other than looking at emited symbols of the compilation,
      we for now skip the problem causing test by default and only run
      it on one specific builder ("linux-amd64").
      Also see CL 42813, which introduced the test and contains comments
      suggesting this temporary solution.
      
      Change-Id: I3978ab0831da04876cf873d78959f821c459282b
      Reviewed-on: https://go-review.googlesource.com/42820Reviewed-by: 's avatarJosh Bleecher Snyder <josharian@gmail.com>
      Reviewed-by: 's avatarBrad Fitzpatrick <bradfitz@golang.org>
      Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
      TryBot-Result: Gobot Gobot <gobot@golang.org>
      8c49c06b
    • Alex Brainman's avatar
      internal/poll: remove allocation in windows FD.Writev · ddcb975f
      Alex Brainman authored
      Use closure parameter instead of external variable to
      remove 1 allocation.
      
      I tried to add test, but it is difficult to add something simple
      and not flake here. I did test this with:
      
      diff --git a/src/net/writev_test.go b/src/net/writev_test.go
      index 4c05be4..e417d68 100644
      --- a/src/net/writev_test.go
      +++ b/src/net/writev_test.go
      @@ -99,6 +99,15 @@ func TestBuffers_WriteTo(t *testing.T) {
       	}
       }
      
      +func TestBuffers_WriteToAllocs(t *testing.T) {
      +	allocs := testing.AllocsPerRun(10, func() {
      +		testBuffer_writeTo(t, 10, false)
      +	})
      +	if allocs > 0 {
      +		t.Fatalf("got %v; want 0", allocs)
      +	}
      +}
      +
       func testBuffer_writeTo(t *testing.T, chunks int, useCopy bool) {
       	oldHook := poll.TestHookDidWritev
       	defer func() { poll.TestHookDidWritev = oldHook }()
      
      It makes allocation count go down by 1 after the fix.
      
      Before:
      
      C:\>u:\test -test.v -test.run=WriteToAllocs
      === RUN   TestBuffers_WriteToAllocs
      --- FAIL: TestBuffers_WriteToAllocs (0.05s)
              writev_test.go:107: got 66; want 0
      FAIL
      
      and after:
      
      C:\>u:\test -test.v -test.run=WriteToAllocs
      === RUN   TestBuffers_WriteToAllocs
      --- FAIL: TestBuffers_WriteToAllocs (0.04s)
              writev_test.go:107: got 65; want 0
      FAIL
      
      Thanks to @MichaelMonashev for report and the fix.
      
      Fixes #19222
      
      Change-Id: I0f73cd9e2c8bbaa0653083f81f3ccb83b5ea84e1
      Reviewed-on: https://go-review.googlesource.com/42893Reviewed-by: 's avatarBrad Fitzpatrick <bradfitz@golang.org>
      Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
      TryBot-Result: Gobot Gobot <gobot@golang.org>
      ddcb975f
  3. 07 May, 2017 5 commits
    • Elias Naur's avatar
      cmd/link/internal/ld: don't link with -no_pie on darwin/arm64 · 45d42fdc
      Elias Naur authored
      Ever since CL 33301 linking darwin/arm64 excutables has resulted in
      warnings like:
      
      ld: warning: -no_pie ignored for arm64
      
      Remove -no_pie on darwin/arm64.
      
      Change-Id: I9f7685351fa8cce29795283e1a24fc7a6753d698
      Reviewed-on: https://go-review.googlesource.com/42815
      Run-TryBot: Elias Naur <elias.naur@gmail.com>
      Reviewed-by: 's avatarBrad Fitzpatrick <bradfitz@golang.org>
      TryBot-Result: Gobot Gobot <gobot@golang.org>
      45d42fdc
    • Kevin Burke's avatar
      os, cmd/link: fix typos · 9058b9ae
      Kevin Burke authored
      Also switch "stating" to "statting" to describe applying os.Stat to
      a resource; the former is more confusable than the latter.
      
      Change-Id: I9d8e3506bd383f8f1479c05948c03b8c633dc4af
      Reviewed-on: https://go-review.googlesource.com/42855Reviewed-by: 's avatarBrad Fitzpatrick <bradfitz@golang.org>
      9058b9ae
    • Marvin Stenger's avatar
      bytes: optimize Buffer's Write, WriteString, WriteByte, and WriteRune · c08ac367
      Marvin Stenger authored
      In the common case, the grow method only needs to reslice the internal
      buffer. Making another function call to grow can be expensive when Write
      is called very often with small pieces of data (like a byte or rune).
      Thus, we add a tryGrowByReslice method that is inlineable so that we can
      avoid an extra call in most cases.
      
      name                       old time/op    new time/op    delta
      WriteByte-4                  35.5µs ± 0%    17.4µs ± 1%   -51.03%  (p=0.000 n=19+20)
      WriteRune-4                  55.7µs ± 1%    38.7µs ± 1%   -30.56%  (p=0.000 n=18+19)
      BufferNotEmptyWriteRead-4     304µs ± 5%     283µs ± 3%    -6.86%  (p=0.000 n=19+17)
      BufferFullSmallReads-4       87.0µs ± 5%    66.8µs ± 2%   -23.26%  (p=0.000 n=17+17)
      
      name                       old speed      new speed      delta
      WriteByte-4                 115MB/s ± 0%   235MB/s ± 1%  +104.19%  (p=0.000 n=19+20)
      WriteRune-4                 221MB/s ± 1%   318MB/s ± 1%   +44.01%  (p=0.000 n=18+19)
      
      Fixes #17857
      
      Change-Id: I08dfb10a1c7e001817729dbfcc951bda12fe8814
      Reviewed-on: https://go-review.googlesource.com/42813Reviewed-by: 's avatarBrad Fitzpatrick <bradfitz@golang.org>
      Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
      TryBot-Result: Gobot Gobot <gobot@golang.org>
      c08ac367
    • Damien Lespiau's avatar
      cmd/asm: enable MOVSD in the encoding end-to-end test · 23c5db9b
      Damien Lespiau authored
      MOVSD is properly handled but its encoding test wasn't enabled. Enable
      it.
      
      For reference this was found with a little tool I wrote [1] to explore
      which instructions are missing or not tested in the go obj package and
      assembler:
      
      "which SSE2 instructions aren't tested? And don't list instructions
      which can take MMX operands"
      
      $ x86db-gogen list --extension SSE2 --not-tested --not-mmx
      CLFLUSH mem           [m:  np 0f ae /7] WILLAMETTE,SSE2
      MOVSD   xmmreg,xmmreg [rm: f2 0f 10 /r] WILLAMETTE,SSE2
      MOVSD   xmmreg,xmmreg [mr: f2 0f 11 /r] WILLAMETTE,SSE2
      MOVSD   mem64,xmmreg  [mr: f2 0f 11 /r] WILLAMETTE,SSE2
      MOVSD   xmmreg,mem64  [rm: f2 0f 10 /r] WILLAMETTE,SSE2
      
      (CLFLUSH was introduced with SSE2, but has its own CPUID bit)
      
      [1] https://github.com/dlespiau/x86db
      
      Change-Id: Ic3af3028cb8d4f02e53fdebb9b30fb311f4ee454
      Reviewed-on: https://go-review.googlesource.com/42814Reviewed-by: 's avatarBrad Fitzpatrick <bradfitz@golang.org>
      Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
      TryBot-Result: Gobot Gobot <gobot@golang.org>
      23c5db9b
    • Alex Brainman's avatar
      os: reimplement windows os.Stat · 53003621
      Alex Brainman authored
      Currently windows Stat uses combination of Lstat and Readlink to
      walk symlinks until it reaches file or directory. Windows Readlink
      is implemented via Windows DeviceIoControl(FSCTL_GET_REPARSE_POINT, ...)
      call, but that call does not work on network shares or inside of
      Docker container (see issues #18555 ad #19922 for details).
      
      But Raymond Chen suggests different approach:
      https://blogs.msdn.microsoft.com/oldnewthing/20100212-00/?p=14963/
      - he suggests to use Windows I/O manager to dereferences the
      symbolic link.
      
      This appears to work for all normal symlinks, but also for network
      shares and inside of Docker container.
      
      This CL implements described procedure.
      
      I also had to adjust TestStatSymlinkLoop, because the test is
      expecting Stat to return syscall.ELOOP for symlink with a loop.
      But new Stat returns Windows error of ERROR_CANT_RESOLVE_FILENAME
      = 1921 instead. I could map ERROR_CANT_RESOLVE_FILENAME into
      syscall.ELOOP, but I suspect the former is broader than later.
      And ERROR_CANT_RESOLVE_FILENAME message text of "The name of
      the file cannot be resolved by the system." sounds fine to me.
      
      Fixes #10935
      Fixes #18555
      Fixes #19922
      
      Change-Id: I979636064cdbdb9c7c840cf8ae73fe2c24499879
      Reviewed-on: https://go-review.googlesource.com/41834Reviewed-by: 's avatarHarshavardhana <hrshvardhana@gmail.com>
      Reviewed-by: 's avatarIan Lance Taylor <iant@golang.org>
      53003621
  4. 06 May, 2017 3 commits
  5. 05 May, 2017 8 commits
    • Robert Griesemer's avatar
      go/types: remove invalid documentation and assertion on package names · 2eeaba41
      Robert Griesemer authored
      NewPackage required through documentation that the package name not
      be blank (which wasn't true since each time we check a new package
      we create one with a blank name (api.go:350). NewPackage also asserted
      that a package name not be "_". While it is invalid for a package name
      to be "_", one could conceivably create a package named "_" through
      export data manipulation. Furthermore, it is ok to import a package
      with package path "_" as long as the package itself is not named "_".
      
      - removed misleading documentation
      - removed unnecessary assertion
      - added safety checks when we actually do the import
      
      Fixes #20231.
      
      Change-Id: I1eb1ab7b5e3130283db715374770cf05d749d159
      Reviewed-on: https://go-review.googlesource.com/42852
      Run-TryBot: Robert Griesemer <gri@golang.org>
      TryBot-Result: Gobot Gobot <gobot@golang.org>
      Reviewed-by: 's avatarAlan Donovan <adonovan@google.com>
      2eeaba41
    • Robert Griesemer's avatar
      go/importer: report import path if package is not found · 0e751829
      Robert Griesemer authored
      Fixes #20230.
      
      Change-Id: I2e9b9e9d2540eb66c8411ac7910962933bc2c0e9
      Reviewed-on: https://go-review.googlesource.com/42870
      Run-TryBot: Robert Griesemer <gri@golang.org>
      TryBot-Result: Gobot Gobot <gobot@golang.org>
      Reviewed-by: 's avatarJosh Bleecher Snyder <josharian@gmail.com>
      0e751829
    • Josh Bleecher Snyder's avatar
      cmd/compile: add Func.SetNilCheckDisabled · 53e62aba
      Josh Bleecher Snyder authored
      Generated hash and eq routines don't need nil checks.
      Prior to this CL, this was accomplished by
      temporarily incrementing the global variable disable_checknil.
      However, that increment lasted only the lifetime of the
      call to funccompile. After CL 41503, funccompile may
      do nothing but enqueue the function for compilation,
      resulting in nil checks being generated.
      
      Fix this by adding an explicit flag to a function
      indicating whether nil checks should be disabled
      for that function.
      
      While we're here, allow concurrent compilation
      with the -w and -W flags, since that was needed
      to investigate this issue.
      
      Fixes #20242
      
      Change-Id: Ib9140c22c49e9a09e62fa3cf350f5d3eff18e2bd
      Reviewed-on: https://go-review.googlesource.com/42591
      Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
      TryBot-Result: Gobot Gobot <gobot@golang.org>
      Reviewed-by: 's avatarMarvin Stenger <marvin.stenger94@gmail.com>
      Reviewed-by: 's avatarRobert Griesemer <gri@golang.org>
      53e62aba
    • Carlos Eduardo Seo's avatar
      cmd/internal/obj/ppc64, cmd/link/internal/ppc64: Change function alignment to 16 · 09b71d56
      Carlos Eduardo Seo authored
      The Power processor manual states that "Branches not from the last instruction
      of an aligned quadword and not to the first instruction of an aligned quadword
      cause inefficiencies in the IBuffer". This changes the function alignment from 8
      to 16 bytes to comply with that.
      
      Fixes #18963
      
      Change-Id: Ibce9bf8302110a86c6ab05948569af9ffdfcf4bb
      Reviewed-on: https://go-review.googlesource.com/36390
      TryBot-Result: Gobot Gobot <gobot@golang.org>
      Reviewed-by: 's avatarDavid Chase <drchase@google.com>
      Run-TryBot: Lynn Boger <laboger@linux.vnet.ibm.com>
      09b71d56
    • Samuel Tan's avatar
      html/template: allow safe usage of predefined escapers in pipelines · 3a2fee03
      Samuel Tan authored
      Allow the predefined escapers "html", "urlquery", and "js" to be used
      in pipelines when they have no potential to affect the correctness or
      safety of the escaped pipeline output. Specifically:
      - "urlquery" may be used if it is the last command in the pipeline.
      - "html" may be used if it is the last command in the pipeline, and
        the pipeline does not occur in an unquoted HTML attribute value
        context.
      - "js" may be used in any pipeline, since it does not affect the
        merging of contextual escapers.
      
      This change will loosens the restrictions on predefined escapers
      introduced in golang.org/cl/37880, which will hopefully ease the
      upgrade path for existing template users.
      
      This change brings back the escaper-merging logic, and associated
      unit tests, that were removed in golang.org/cl/37880. However, a
      few notable changes have been made:
      - "_html_template_nospaceescaper" is no longer considered
        equivalent to "html", since the former escapes spaces, while
        the latter does not (see #19345). This change should not silently
        break any templates, since pipelines where this substituion will
        happen will already trigger an explicit error.
      - An "_eval_args_" internal directive has been added to
        handle pipelines containing a single explicit call to a
        predefined escaper, e.g. {{html .X}} (see #19353).
      
      Also, the HTMLEscape function called by the predefined
      text/template "html" function now escapes the NULL character as
      well. This effectively makes it as secure as the internal
      html/template HTML escapers (see #19345). While this change is
      backward-incompatible, it will only affect illegitimate uses
      of this escaper, since the NULL character is always illegal in
      valid HTML.
      
      Fixes #19952
      
      Change-Id: I9b5570a80a3ea284b53901e6a1f842fc59b33d3a
      Reviewed-on: https://go-review.googlesource.com/40936Reviewed-by: 's avatarRuss Cox <rsc@golang.org>
      Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
      TryBot-Result: Gobot Gobot <gobot@golang.org>
      3a2fee03
    • Dieter Plaetinck's avatar
      template: warn about interleaved nature of writes · 1acff5fe
      Dieter Plaetinck authored
      Execute incurs separate writes for each "step", e.g. each
      variable that needs to be printed, and the final newline.
      While it is correct to state that templates can be executed
      concurrently, there is a more subtle nuance that is easily missed:
      when writing to the same writer, the writes from concurrent execute
      calls can be interleaved, leading to unexpected output.
      
      Change-Id: I0abbd7960d8a8d15e109a8a3eeff3b43b852bbbf
      Reviewed-on: https://go-review.googlesource.com/37444Reviewed-by: 's avatarRob Pike <r@golang.org>
      1acff5fe
    • David Crawshaw's avatar
      cmd/link: stop passing unused read_only_relocs · 27a10f7d
      David Crawshaw authored
      The external darwin linker has been printing:
      
      	ld: warning: -read_only_relocs cannot be used with x86_64
      
      for a long time. Now that it is printed by CL 33301, we may as
      well get rid of it.
      
      Fixes #20246
      
      Change-Id: I1147cf1ff197fdfda228a1349f13627bcf9fc72f
      Reviewed-on: https://go-review.googlesource.com/42730
      Run-TryBot: David Crawshaw <crawshaw@golang.org>
      TryBot-Result: Gobot Gobot <gobot@golang.org>
      Reviewed-by: 's avatarTodd Neal <todd@tneal.org>
      Reviewed-by: 's avatarBrad Fitzpatrick <bradfitz@golang.org>
      27a10f7d
    • Alex Brainman's avatar
      cmd/link: do not read .bss sections in ldpe · 507f4d5f
      Alex Brainman authored
      For .bss section symbol ldelf does not set P (raw symbol data).
      Make ldpe do the same.
      
      Change-Id: Ib3d558456f505ee568d0972465fa9b08b5794a87
      Reviewed-on: https://go-review.googlesource.com/42631Reviewed-by: 's avatarIan Lance Taylor <iant@golang.org>
      Run-TryBot: Ian Lance Taylor <iant@golang.org>
      TryBot-Result: Gobot Gobot <gobot@golang.org>
      507f4d5f
  6. 04 May, 2017 6 commits