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Commit Graph

38138 Commits

Author SHA1 Message Date
Josh Bleecher Snyder
a55f3ee46d cmd/compile: fuse before branchelim
The branchelim pass works better after fuse.
Running fuse before branchelim also increases
the stability of generated code amidst other compiler changes,
which was the original motivation behind this change.

The fuse pass is not cheap enough to run in its entirety
before branchelim, but the most important half of it is.
This change makes it possible to run "plain fuse" independently
and does so before branchelim.

During make.bash, elimIf occurrences increase from 4244 to 4288 (1%),
and elimIfElse occurrences increase from 989 to 1079 (9%).

Toolspeed impact is marginal; plain fuse pays for itself.

name        old time/op       new time/op       delta
Template          189ms ± 2%        189ms ± 2%    ~     (p=0.890 n=45+46)
Unicode          93.2ms ± 5%       93.4ms ± 7%    ~     (p=0.790 n=48+48)
GoTypes           662ms ± 4%        660ms ± 4%    ~     (p=0.186 n=48+49)
Compiler          2.89s ± 4%        2.91s ± 3%  +0.89%  (p=0.050 n=49+44)
SSA               8.23s ± 2%        8.21s ± 1%    ~     (p=0.165 n=46+44)
Flate             123ms ± 4%        123ms ± 3%  +0.58%  (p=0.031 n=47+49)
GoParser          154ms ± 4%        154ms ± 4%    ~     (p=0.492 n=49+48)
Reflect           430ms ± 4%        429ms ± 4%    ~     (p=1.000 n=48+48)
Tar               171ms ± 3%        170ms ± 4%    ~     (p=0.122 n=48+48)
XML               232ms ± 3%        232ms ± 2%    ~     (p=0.850 n=46+49)
[Geo mean]        394ms             394ms       +0.02%

name        old user-time/op  new user-time/op  delta
Template          236ms ± 5%        236ms ± 4%    ~     (p=0.934 n=50+50)
Unicode           132ms ± 7%        130ms ± 9%    ~     (p=0.087 n=50+50)
GoTypes           861ms ± 3%        867ms ± 4%    ~     (p=0.124 n=48+50)
Compiler          3.93s ± 4%        3.94s ± 3%    ~     (p=0.584 n=49+44)
SSA               12.2s ± 2%        12.3s ± 1%    ~     (p=0.610 n=46+45)
Flate             149ms ± 4%        150ms ± 4%    ~     (p=0.194 n=48+49)
GoParser          193ms ± 5%        191ms ± 6%    ~     (p=0.239 n=49+50)
Reflect           553ms ± 5%        556ms ± 5%    ~     (p=0.091 n=49+49)
Tar               218ms ± 5%        218ms ± 5%    ~     (p=0.359 n=49+50)
XML               299ms ± 5%        298ms ± 4%    ~     (p=0.482 n=50+49)
[Geo mean]        516ms             516ms       -0.01%

name        old alloc/op      new alloc/op      delta
Template         36.3MB ± 0%       36.3MB ± 0%  -0.02%  (p=0.000 n=49+49)
Unicode          29.7MB ± 0%       29.7MB ± 0%    ~     (p=0.270 n=50+50)
GoTypes           126MB ± 0%        126MB ± 0%  -0.34%  (p=0.000 n=50+49)
Compiler          534MB ± 0%        531MB ± 0%  -0.50%  (p=0.000 n=50+50)
SSA              1.98GB ± 0%       1.98GB ± 0%  -0.06%  (p=0.000 n=49+49)
Flate            24.6MB ± 0%       24.6MB ± 0%  -0.29%  (p=0.000 n=50+50)
GoParser         29.5MB ± 0%       29.4MB ± 0%  -0.15%  (p=0.000 n=49+50)
Reflect          87.3MB ± 0%       87.2MB ± 0%  -0.13%  (p=0.000 n=49+50)
Tar              35.6MB ± 0%       35.5MB ± 0%  -0.17%  (p=0.000 n=50+50)
XML              48.2MB ± 0%       48.0MB ± 0%  -0.30%  (p=0.000 n=48+50)
[Geo mean]       83.1MB            82.9MB       -0.20%

name        old allocs/op     new allocs/op     delta
Template           352k ± 0%         352k ± 0%  -0.01%  (p=0.004 n=49+49)
Unicode            341k ± 0%         341k ± 0%    ~     (p=0.341 n=48+50)
GoTypes           1.28M ± 0%        1.28M ± 0%  -0.03%  (p=0.000 n=50+49)
Compiler          4.96M ± 0%        4.96M ± 0%  -0.05%  (p=0.000 n=50+49)
SSA               15.5M ± 0%        15.5M ± 0%  -0.01%  (p=0.000 n=50+49)
Flate              233k ± 0%         233k ± 0%  +0.01%  (p=0.032 n=49+49)
GoParser           294k ± 0%         294k ± 0%    ~     (p=0.052 n=46+48)
Reflect           1.04M ± 0%        1.04M ± 0%    ~     (p=0.171 n=50+47)
Tar                343k ± 0%         343k ± 0%  -0.03%  (p=0.000 n=50+50)
XML                429k ± 0%         429k ± 0%  -0.04%  (p=0.000 n=50+50)
[Geo mean]         812k              812k       -0.02%

Object files grow slightly; branchelim often increases binary size, at least on amd64.

name        old object-bytes  new object-bytes  delta
Template          509kB ± 0%        509kB ± 0%  -0.01%  (p=0.008 n=5+5)
Unicode           224kB ± 0%        224kB ± 0%    ~     (all equal)
GoTypes          1.84MB ± 0%       1.84MB ± 0%  +0.00%  (p=0.008 n=5+5)
Compiler         6.71MB ± 0%       6.71MB ± 0%  +0.01%  (p=0.008 n=5+5)
SSA              21.2MB ± 0%       21.2MB ± 0%  +0.01%  (p=0.008 n=5+5)
Flate             324kB ± 0%        324kB ± 0%  -0.00%  (p=0.008 n=5+5)
GoParser          404kB ± 0%        404kB ± 0%  -0.02%  (p=0.008 n=5+5)
Reflect          1.40MB ± 0%       1.40MB ± 0%  +0.09%  (p=0.008 n=5+5)
Tar               452kB ± 0%        452kB ± 0%  +0.06%  (p=0.008 n=5+5)
XML               596kB ± 0%        596kB ± 0%  +0.00%  (p=0.008 n=5+5)
[Geo mean]       1.04MB            1.04MB       +0.01%

Change-Id: I535c711b85380ff657fc0f022bebd9cb14ddd07f
Reviewed-on: https://go-review.googlesource.com/c/129378
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2018-10-15 16:51:08 +00:00
Keith Randall
63e964e174 cmd/compile: provide types for all order-allocated temporaries
Ensure that we correctly type the stack temps for regular closures,
method function closures, and slice literals.

Then we don't need to override the dummy types later.
Furthermore, this allows order to reuse temporaries of these types.

OARRAYLIT doesn't need a temporary as far as I can tell, so I
removed that case from order.

Change-Id: Ic58520fa50c90639393ff78f33d3c831d5c4acb9
Reviewed-on: https://go-review.googlesource.com/c/140306
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2018-10-15 16:07:52 +00:00
Keith Randall
296b7aeae0 cmd/compile: fix gdb stepping test
Not sure why this changed behavior, but seems mostly harmless.

Fixes #28198

Change-Id: Ie25c6e1fcb64912a582c7ae7bf92c4c1642e83cb
Reviewed-on: https://go-review.googlesource.com/c/141649
Reviewed-by: David Chase <drchase@google.com>
2018-10-15 16:01:56 +00:00
Ben Shi
93e27e01af test/codegen: add tests of FMA for arm/arm64
This CL adds tests of fused multiplication-accumulation
on arm/arm64.

Change-Id: Ic85d5277c0d6acb7e1e723653372dfaf96824a39
Reviewed-on: https://go-review.googlesource.com/c/141652
Run-TryBot: Ben Shi <powerman1st@163.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2018-10-15 14:51:30 +00:00
Akhil Indurti
bb3bf5bb53 internal/cpu: expose ARM feature flags for FMA
This change exposes feature flags needed to implement an FMA intrinsic
on ARM CPUs via auxv's HWCAP bits. Specifically, it exposes HasVFPv4 to
detect if an ARM processor has the fourth version of the vector floating
point unit. The relevant instruction for this CL is VFMA, emitted in Go
as FMULAD.

Updates #26630.

Change-Id: Ibbc04fb24c2b4d994f93762360f1a37bc6d83ff7
Reviewed-on: https://go-review.googlesource.com/c/126315
Run-TryBot: Martin Möhrmann <moehrmann@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Martin Möhrmann <moehrmann@google.com>
2018-10-15 10:57:04 +00:00
Martin Möhrmann
d6e80069f3 cmd/compile: simplify as2 method of *Order
Merge the two for loops that set up the node lists for
temporaries into one for loop.

Passes toolstash -cmp

Change-Id: Ibc739115f38c8869b0dcfbf9819fdc2fc96962e0
Reviewed-on: https://go-review.googlesource.com/c/141819
Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: Martin Möhrmann <moehrmann@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2018-10-15 07:34:56 +00:00
avsharapov
9322b53396 cmd/cgo: simplify switch statement to if statement
Change-Id: Ie7dce45d554fde69d682680f55abba6a7fc55036
Reviewed-on: https://go-review.googlesource.com/c/142017
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2018-10-15 04:36:11 +00:00
Ivan Sharavuev
e47c11d8b1 pprof: replace bits = bits + "..." to bits += "..." where bits is a string.
Change-Id: Ic77ebbdf2670b7fdf2c381cd1ba768624b07e57c
Reviewed-on: https://go-review.googlesource.com/c/141998
Run-TryBot: Iskander Sharipov <iskander.sharipov@intel.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2018-10-15 04:27:52 +00:00
OlgaVlPetrova
85066acca1 src/cmd/compile/internal/ssa: replace `s = s + x' => 's += x'.
Change-Id: I1f399a8a0aa200bfda01f97f920b1345e59956ba
Reviewed-on: https://go-review.googlesource.com/c/142057
Run-TryBot: Iskander Sharipov <iskander.sharipov@intel.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2018-10-15 04:19:20 +00:00
Ben Shi
c3208842e1 test/codegen: add tests for multiplication-subtraction
This CL adds tests for armv7's MULS and arm64's MSUBW.

Change-Id: Id0fd5d26fd477e4ed14389b0d33cad930423eb5b
Reviewed-on: https://go-review.googlesource.com/c/141651
Run-TryBot: Ben Shi <powerman1st@163.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2018-10-15 02:41:33 +00:00
Keith Randall
389e942745 cmd/compile: reuse temporaries in order pass
Instead of allocating a new temporary each time one
is needed, keep a list of temporaries which are free
(have already been VARKILLed on every path) and use
one of them.

Should save a lot of stack space. In a function like this:

func main() {
     fmt.Printf("%d %d\n", 2, 3)
     fmt.Printf("%d %d\n", 4, 5)
     fmt.Printf("%d %d\n", 6, 7)
}

The three [2]interface{} arrays used to hold the ... args
all use the same autotmp, instead of 3 different autotmps
as happened previous to this CL.

Change-Id: I2d728e226f81e05ae68ca8247af62014a1b032d3
Reviewed-on: https://go-review.googlesource.com/c/140301
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2018-10-14 05:21:00 +00:00
Keith Randall
0e9f8a21f8 runtime,cmd/compile: pass strings and slices to convT2{E,I} by value
When we pass these types by reference, we usually have to allocate
temporaries on the stack, initialize them, then pass their address
to the conversion functions. It's simpler to pass these types
directly by value.

This particularly applies to conversions needed for fmt.Printf
(to interface{} for constructing a [...]interface{}).

func f(a, b, c string) {
     fmt.Printf("%s %s\n", a, b)
     fmt.Printf("%s %s\n", b, c)
}

This function's stack frame shrinks from 200 to 136 bytes, and
its code shrinks from 535 to 453 bytes.

The go binary shrinks 0.3%.

Update #24286

Aside: for this function f, we don't really need to allocate
temporaries for the convT2E function. We could use the address
of a, b, and c directly. That might get similar (or maybe better?)
improvements. I investigated a bit, but it seemed complicated
to do it safely. This change was much easier.

Change-Id: I78cbe51b501fb41e1e324ce4203f0de56a1db82d
Reviewed-on: https://go-review.googlesource.com/c/135377
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
2018-10-14 03:46:51 +00:00
Keith Randall
653a4bd8d4 cmd/compile: optimize loads from readonly globals into constants
Instead of
   MOVB go.string."foo"(SB), AX
do
   MOVB $102, AX

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

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

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

Update #26498

Change-Id: I41b1dc831b2cd0a52dac9b97f4f4457888a46389
Reviewed-on: https://go-review.googlesource.com/c/141118
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
2018-10-14 02:54:40 +00:00
Keith Randall
df459d5e6c cmd/compile: emit symbol for constant string before parallel compiler phase
This CL makes sure we walk the newly generated assignment. Part of
that walk makes sure that all symbols for strings are emitted before
we start referencing them during the parallel compilation
phase. Without this change, those references during the parallel phase
do a create-if-not-exist, which leads to a data race.

I'm not 100% sure this is the fix for the issues below, but optimistically
assuming it is...

Fixes #28170
Fixes #28159

Change-Id: Ic63d5160ad9be5cb23fa6bbb2183e4848776c0ff
Reviewed-on: https://go-review.googlesource.com/c/141648
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2018-10-13 23:11:30 +00:00
OlgaVlPetrova
4330866385 debug/plan9obj: simplify s[:] to s where
Change-Id: Ib2eee1215ba046e4541af8afa3a921c680d2b37e
Reviewed-on: https://go-review.googlesource.com/c/142037
Run-TryBot: Iskander Sharipov <iskander.sharipov@intel.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Iskander Sharipov <iskander.sharipov@intel.com>
2018-10-13 11:24:43 +00:00
avsharapov
e489a236b4 jpeg: simplify 'x = x op ...' to 'x op= ...'
Change-Id: Id431969e42f0d9bd28bbf163d10378a6de2416f2
Reviewed-on: https://go-review.googlesource.com/c/141999
Run-TryBot: Iskander Sharipov <iskander.sharipov@intel.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Iskander Sharipov <iskander.sharipov@intel.com>
2018-10-13 11:18:56 +00:00
Ivan Sharavuev
c4f07510a0 strings: Replace s[:] to s where s is a slice.
Change-Id: Ie7ba3f9ece9b0fc0e8a5c92fbae9c3b558815e4c
Reviewed-on: https://go-review.googlesource.com/c/141997
Run-TryBot: Iskander Sharipov <iskander.sharipov@intel.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Iskander Sharipov <iskander.sharipov@intel.com>
2018-10-13 11:17:13 +00:00
Matthew Dempsky
b4150f7614 cmd/compile: remove ineffectual -i flag
This flag lost its usefulness in CL 34273.

Change-Id: I033c29f105937139b4e359a340906be439f1ed07
Reviewed-on: https://go-review.googlesource.com/c/141646
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Robert Griesemer <gri@golang.org>
2018-10-12 23:17:42 +00:00
Mak Kolybabi
5745652756 doc: fix spelling of comp[]hensive to comp[r]ehensive
Change-Id: Idd93e45fab30e7496105b84fc2fce1884711b580
GitHub-Last-Rev: 43aa04e876
GitHub-Pull-Request: golang/go#27983
Reviewed-on: https://go-review.googlesource.com/c/141645
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2018-10-12 22:59:05 +00:00
Russ Cox
bf68744a12 regexp: add partial Deprecation comment to Copy
Change-Id: I21b7817e604a48330f1ee250f7b1b2adc1f16067
Reviewed-on: https://go-review.googlesource.com/c/139784
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-10-12 17:48:44 +00:00
Russ Cox
5160e0d18c regexp: add DeepEqual test
This locks in behavior we accidentally broke
and then restored during the Go 1.11 cycle.
See #26219.

It also locks in new behavior that DeepEqual
always works, instead of only usually working.

This CL is the final piece of a series of CLs to make
DeepEqual always work, by eliminating the machine
cache and making other related optimizations.
Overall, this whole sequence of CLs achieves:

name                             old time/op    new time/op    delta
Find-12                             264ns ± 3%     260ns ± 0%   -1.59%  (p=0.000 n=10+9)
FindAllNoMatches-12                 140ns ± 2%     133ns ± 0%   -5.34%  (p=0.000 n=10+7)
FindString-12                       256ns ± 0%     249ns ± 0%   -2.73%  (p=0.000 n=8+8)
FindSubmatch-12                     339ns ± 1%     333ns ± 1%   -1.73%  (p=0.000 n=9+10)
FindStringSubmatch-12               322ns ± 0%     322ns ± 1%     ~     (p=0.450 n=8+10)
Literal-12                          100ns ± 2%      92ns ± 0%   -8.13%  (p=0.000 n=10+10)
NotLiteral-12                      1.50µs ± 0%    1.47µs ± 0%   -1.65%  (p=0.000 n=8+8)
MatchClass-12                      2.18µs ± 0%    2.15µs ± 0%   -1.05%  (p=0.000 n=10+9)
MatchClass_InRange-12              2.12µs ± 0%    2.11µs ± 0%   -0.65%  (p=0.000 n=10+9)
ReplaceAll-12                      1.41µs ± 0%    1.41µs ± 0%     ~     (p=0.254 n=7+10)
AnchoredLiteralShortNonMatch-12    89.8ns ± 0%    81.5ns ± 0%   -9.22%  (p=0.000 n=8+9)
AnchoredLiteralLongNonMatch-12      105ns ± 3%      97ns ± 0%   -7.21%  (p=0.000 n=10+10)
AnchoredShortMatch-12               141ns ± 0%     128ns ± 0%   -9.22%  (p=0.000 n=9+9)
AnchoredLongMatch-12                276ns ± 4%     253ns ± 2%   -8.23%  (p=0.000 n=10+10)
OnePassShortA-12                    620ns ± 0%     587ns ± 0%   -5.26%  (p=0.000 n=10+6)
NotOnePassShortA-12                 575ns ± 3%     547ns ± 1%   -4.77%  (p=0.000 n=10+10)
OnePassShortB-12                    493ns ± 0%     455ns ± 0%   -7.62%  (p=0.000 n=8+9)
NotOnePassShortB-12                 423ns ± 0%     406ns ± 1%   -3.95%  (p=0.000 n=8+10)
OnePassLongPrefix-12                112ns ± 0%     109ns ± 1%   -2.77%  (p=0.000 n=9+10)
OnePassLongNotPrefix-12             405ns ± 0%     349ns ± 0%  -13.74%  (p=0.000 n=8+9)
MatchParallelShared-12              501ns ± 1%      38ns ± 2%  -92.42%  (p=0.000 n=10+10)
MatchParallelCopied-12             39.1ns ± 0%    38.6ns ± 1%   -1.38%  (p=0.002 n=6+10)
QuoteMetaAll-12                    94.6ns ± 0%    94.8ns ± 0%   +0.26%  (p=0.001 n=10+9)
QuoteMetaNone-12                   52.7ns ± 0%    52.7ns ± 0%     ~     (all equal)
Match/Easy0/32-12                  79.1ns ± 0%    72.0ns ± 0%   -8.95%  (p=0.000 n=9+9)
Match/Easy0/1K-12                   307ns ± 1%     297ns ± 0%   -3.32%  (p=0.000 n=10+7)
Match/Easy0/32K-12                 4.65µs ± 2%    4.67µs ± 1%     ~     (p=0.633 n=10+8)
Match/Easy0/1M-12                   234µs ± 0%     234µs ± 0%     ~     (p=0.684 n=10+10)
Match/Easy0/32M-12                 7.98ms ± 1%    7.96ms ± 0%   -0.31%  (p=0.014 n=9+9)
Match/Easy0i/32-12                 1.13µs ± 1%    1.10µs ± 0%   -3.18%  (p=0.000 n=9+10)
Match/Easy0i/1K-12                 32.5µs ± 0%    31.7µs ± 0%   -2.61%  (p=0.000 n=9+9)
Match/Easy0i/32K-12                1.59ms ± 0%    1.26ms ± 0%  -20.71%  (p=0.000 n=9+7)
Match/Easy0i/1M-12                 51.0ms ± 0%    40.4ms ± 0%  -20.68%  (p=0.000 n=10+7)
Match/Easy0i/32M-12                 1.63s ± 0%     1.30s ± 0%  -20.62%  (p=0.001 n=7+7)
Match/Easy1/32-12                  75.1ns ± 1%    67.4ns ± 0%  -10.24%  (p=0.000 n=8+10)
Match/Easy1/1K-12                   861ns ± 0%     879ns ± 0%   +2.18%  (p=0.000 n=8+8)
Match/Easy1/32K-12                 39.2µs ± 1%    34.1µs ± 0%  -13.01%  (p=0.000 n=10+8)
Match/Easy1/1M-12                  1.38ms ± 0%    1.17ms ± 0%  -15.06%  (p=0.000 n=10+8)
Match/Easy1/32M-12                 44.2ms ± 1%    37.5ms ± 0%  -15.15%  (p=0.000 n=10+9)
Match/Medium/32-12                 1.04µs ± 1%    1.03µs ± 0%   -0.64%  (p=0.002 n=9+8)
Match/Medium/1K-12                 31.3µs ± 0%    31.2µs ± 0%   -0.36%  (p=0.000 n=9+9)
Match/Medium/32K-12                1.44ms ± 0%    1.20ms ± 0%  -17.02%  (p=0.000 n=8+7)
Match/Medium/1M-12                 46.1ms ± 0%    38.2ms ± 0%  -17.14%  (p=0.001 n=6+8)
Match/Medium/32M-12                 1.48s ± 0%     1.23s ± 0%  -17.10%  (p=0.000 n=9+7)
Match/Hard/32-12                   1.54µs ± 1%    1.47µs ± 0%   -4.64%  (p=0.000 n=9+10)
Match/Hard/1K-12                   46.4µs ± 1%    44.4µs ± 0%   -4.35%  (p=0.000 n=9+8)
Match/Hard/32K-12                  2.19ms ± 0%    1.78ms ± 7%  -18.74%  (p=0.000 n=8+10)
Match/Hard/1M-12                   70.1ms ± 0%    57.7ms ± 7%  -17.62%  (p=0.000 n=8+10)
Match/Hard/32M-12                   2.24s ± 0%     1.84s ± 8%  -17.92%  (p=0.000 n=8+10)
Match/Hard1/32-12                  8.17µs ± 1%    7.95µs ± 0%   -2.72%  (p=0.000 n=8+10)
Match/Hard1/1K-12                   254µs ± 2%     245µs ± 0%   -3.62%  (p=0.000 n=9+10)
Match/Hard1/32K-12                 9.58ms ± 1%    8.54ms ± 7%  -10.87%  (p=0.000 n=10+10)
Match/Hard1/1M-12                   306ms ± 1%     271ms ± 8%  -11.42%  (p=0.000 n=9+10)
Match/Hard1/32M-12                  9.79s ± 1%     8.58s ± 9%  -12.37%  (p=0.000 n=9+10)
Match_onepass_regex/32-12           808ns ± 0%     716ns ± 1%  -11.39%  (p=0.000 n=8+9)
Match_onepass_regex/1K-12          27.8µs ± 0%    19.9µs ± 2%  -28.51%  (p=0.000 n=8+9)
Match_onepass_regex/32K-12          925µs ± 0%     631µs ± 2%  -31.71%  (p=0.000 n=9+9)
Match_onepass_regex/1M-12          29.5ms ± 0%    20.2ms ± 2%  -31.53%  (p=0.000 n=10+9)
Match_onepass_regex/32M-12          945ms ± 0%     648ms ± 2%  -31.39%  (p=0.000 n=9+9)
CompileOnepass-12                  4.67µs ± 0%    4.60µs ± 0%   -1.48%  (p=0.000 n=10+10)
[Geo mean]                         24.5µs         21.4µs       -12.94%

https://perf.golang.org/search?q=upload:20181004.5

Change-Id: Icb17b306830dc5489efbb55900937b94ce0eb047
Reviewed-on: https://go-review.googlesource.com/c/139783
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-10-12 17:48:42 +00:00
Russ Cox
3ca1f28e54 regexp: evaluate context flags lazily
There's no point in computing whether we're at the
beginning of the line if the NFA isn't going to ask.
Wait to compute that until asked.

Whatever minor slowdowns were introduced by
the conversion to pools that were not repaid by
other optimizations are taken care of by this one.

name                             old time/op    new time/op    delta
Find-12                             252ns ± 0%     260ns ± 0%   +3.34%  (p=0.000 n=10+8)
FindAllNoMatches-12                 136ns ± 4%     134ns ± 4%   -0.96%  (p=0.033 n=10+10)
FindString-12                       246ns ± 0%     250ns ± 0%   +1.46%  (p=0.000 n=8+10)
FindSubmatch-12                     332ns ± 1%     332ns ± 0%     ~     (p=0.101 n=9+10)
FindStringSubmatch-12               321ns ± 1%     322ns ± 1%     ~     (p=0.717 n=9+10)
Literal-12                         91.6ns ± 0%    92.3ns ± 0%   +0.74%  (p=0.000 n=9+9)
NotLiteral-12                      1.47µs ± 0%    1.47µs ± 0%   +0.38%  (p=0.000 n=9+8)
MatchClass-12                      2.15µs ± 0%    2.15µs ± 0%   +0.39%  (p=0.000 n=10+10)
MatchClass_InRange-12              2.09µs ± 0%    2.11µs ± 0%   +0.75%  (p=0.000 n=9+9)
ReplaceAll-12                      1.40µs ± 0%    1.40µs ± 0%     ~     (p=0.525 n=10+10)
AnchoredLiteralShortNonMatch-12    83.5ns ± 0%    81.6ns ± 0%   -2.28%  (p=0.000 n=9+10)
AnchoredLiteralLongNonMatch-12      101ns ± 0%      97ns ± 1%   -3.54%  (p=0.000 n=10+10)
AnchoredShortMatch-12               131ns ± 0%     128ns ± 0%   -2.29%  (p=0.000 n=10+9)
AnchoredLongMatch-12                268ns ± 1%     252ns ± 1%   -6.04%  (p=0.000 n=10+10)
OnePassShortA-12                    614ns ± 0%     587ns ± 1%   -4.33%  (p=0.000 n=6+10)
NotOnePassShortA-12                 552ns ± 0%     547ns ± 1%   -0.89%  (p=0.000 n=10+10)
OnePassShortB-12                    494ns ± 0%     455ns ± 0%   -7.96%  (p=0.000 n=9+9)
NotOnePassShortB-12                 411ns ± 0%     406ns ± 0%   -1.30%  (p=0.000 n=9+9)
OnePassLongPrefix-12                109ns ± 0%     108ns ± 1%     ~     (p=0.064 n=8+9)
OnePassLongNotPrefix-12             403ns ± 0%     349ns ± 0%  -13.30%  (p=0.000 n=9+8)
MatchParallelShared-12             38.9ns ± 1%    37.9ns ± 1%   -2.65%  (p=0.000 n=10+8)
MatchParallelCopied-12             39.2ns ± 1%    38.3ns ± 2%   -2.20%  (p=0.001 n=10+10)
QuoteMetaAll-12                    94.5ns ± 0%    94.7ns ± 0%   +0.18%  (p=0.043 n=10+9)
QuoteMetaNone-12                   52.7ns ± 0%    52.7ns ± 0%     ~     (all equal)
Match/Easy0/32-12                  72.2ns ± 0%    71.9ns ± 0%   -0.38%  (p=0.009 n=8+10)
Match/Easy0/1K-12                   296ns ± 1%     297ns ± 0%   +0.51%  (p=0.001 n=10+9)
Match/Easy0/32K-12                 4.57µs ± 3%    4.61µs ± 2%     ~     (p=0.280 n=10+10)
Match/Easy0/1M-12                   234µs ± 0%     234µs ± 0%     ~     (p=0.986 n=10+10)
Match/Easy0/32M-12                 7.96ms ± 0%    7.98ms ± 0%   +0.22%  (p=0.010 n=10+9)
Match/Easy0i/32-12                 1.09µs ± 0%    1.10µs ± 0%   +0.23%  (p=0.000 n=8+9)
Match/Easy0i/1K-12                 31.7µs ± 0%    31.7µs ± 0%   +0.09%  (p=0.003 n=9+8)
Match/Easy0i/32K-12                1.61ms ± 0%    1.27ms ± 1%  -21.03%  (p=0.000 n=8+10)
Match/Easy0i/1M-12                 51.4ms ± 0%    40.4ms ± 0%  -21.29%  (p=0.000 n=8+8)
Match/Easy0i/32M-12                 1.65s ± 0%     1.30s ± 1%  -21.22%  (p=0.000 n=9+9)
Match/Easy1/32-12                  67.6ns ± 1%    67.2ns ± 0%     ~     (p=0.085 n=10+9)
Match/Easy1/1K-12                   873ns ± 2%     880ns ± 0%   +0.78%  (p=0.006 n=9+7)
Match/Easy1/32K-12                 39.7µs ± 1%    34.3µs ± 3%  -13.53%  (p=0.000 n=10+10)
Match/Easy1/1M-12                  1.41ms ± 1%    1.19ms ± 3%  -15.48%  (p=0.000 n=10+10)
Match/Easy1/32M-12                 44.9ms ± 1%    38.0ms ± 2%  -15.21%  (p=0.000 n=10+10)
Match/Medium/32-12                 1.04µs ± 0%    1.03µs ± 0%   -0.57%  (p=0.000 n=9+9)
Match/Medium/1K-12                 31.2µs ± 0%    31.4µs ± 1%   +0.61%  (p=0.000 n=8+10)
Match/Medium/32K-12                1.45ms ± 1%    1.20ms ± 0%  -17.70%  (p=0.000 n=10+8)
Match/Medium/1M-12                 46.4ms ± 0%    38.4ms ± 2%  -17.32%  (p=0.000 n=6+9)
Match/Medium/32M-12                 1.49s ± 1%     1.24s ± 1%  -16.81%  (p=0.000 n=10+10)
Match/Hard/32-12                   1.47µs ± 0%    1.47µs ± 0%   -0.31%  (p=0.000 n=9+10)
Match/Hard/1K-12                   44.5µs ± 1%    44.4µs ± 0%     ~     (p=0.075 n=10+10)
Match/Hard/32K-12                  2.09ms ± 0%    1.78ms ± 7%  -14.88%  (p=0.000 n=8+10)
Match/Hard/1M-12                   67.8ms ± 5%    56.9ms ± 7%  -16.05%  (p=0.000 n=10+10)
Match/Hard/32M-12                   2.17s ± 5%     1.84s ± 6%  -15.21%  (p=0.000 n=10+10)
Match/Hard1/32-12                  7.89µs ± 0%    7.94µs ± 0%   +0.61%  (p=0.000 n=9+9)
Match/Hard1/1K-12                   246µs ± 0%     245µs ± 0%   -0.30%  (p=0.010 n=9+10)
Match/Hard1/32K-12                 8.93ms ± 0%    8.17ms ± 0%   -8.44%  (p=0.000 n=9+8)
Match/Hard1/1M-12                   286ms ± 0%     269ms ± 9%   -5.66%  (p=0.028 n=9+10)
Match/Hard1/32M-12                  9.16s ± 0%     8.61s ± 8%   -5.98%  (p=0.028 n=9+10)
Match_onepass_regex/32-12           825ns ± 0%     712ns ± 0%  -13.75%  (p=0.000 n=8+8)
Match_onepass_regex/1K-12          28.7µs ± 1%    19.8µs ± 0%  -30.99%  (p=0.000 n=9+8)
Match_onepass_regex/32K-12          950µs ± 1%     628µs ± 0%  -33.83%  (p=0.000 n=9+8)
Match_onepass_regex/1M-12          30.4ms ± 0%    20.1ms ± 0%  -33.74%  (p=0.000 n=9+8)
Match_onepass_regex/32M-12          974ms ± 1%     646ms ± 0%  -33.73%  (p=0.000 n=9+8)
CompileOnepass-12                  4.60µs ± 0%    4.59µs ± 0%     ~     (p=0.063 n=8+9)
[Geo mean]                         23.1µs         21.3µs        -7.44%

https://perf.golang.org/search?q=upload:20181004.4

Change-Id: I47cdd09f6dcde1d7c317080e9b4df42c7d0a8d24
Reviewed-on: https://go-review.googlesource.com/c/139782
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-10-12 17:48:41 +00:00
Russ Cox
a376435ae5 regexp: use pools for NFA machines
Now the machine struct is only used for NFA execution.
Use global pools to cache machines instead of per-Regexp lists.

Also eliminate some tail calls in NFA execution, to pay for
the added overhead of sync.Pool.

name                             old time/op    new time/op    delta
Find-12                             252ns ± 0%     252ns ± 0%     ~     (p=1.000 n=10+10)
FindAllNoMatches-12                 134ns ± 1%     136ns ± 4%     ~     (p=0.443 n=9+10)
FindString-12                       246ns ± 0%     246ns ± 0%   -0.16%  (p=0.046 n=10+8)
FindSubmatch-12                     333ns ± 2%     332ns ± 1%     ~     (p=0.489 n=10+9)
FindStringSubmatch-12               320ns ± 0%     321ns ± 1%   +0.55%  (p=0.005 n=10+9)
Literal-12                         91.1ns ± 0%    91.6ns ± 0%   +0.55%  (p=0.000 n=10+9)
NotLiteral-12                      1.45µs ± 0%    1.47µs ± 0%   +0.82%  (p=0.000 n=10+9)
MatchClass-12                      2.19µs ± 0%    2.15µs ± 0%   -2.01%  (p=0.000 n=9+10)
MatchClass_InRange-12              2.09µs ± 0%    2.09µs ± 0%     ~     (p=0.082 n=10+9)
ReplaceAll-12                      1.39µs ± 0%    1.40µs ± 0%   +0.50%  (p=0.000 n=10+10)
AnchoredLiteralShortNonMatch-12    82.4ns ± 0%    83.5ns ± 0%   +1.36%  (p=0.000 n=8+9)
AnchoredLiteralLongNonMatch-12      106ns ± 1%     101ns ± 0%   -4.36%  (p=0.000 n=10+10)
AnchoredShortMatch-12               130ns ± 0%     131ns ± 0%   +0.77%  (p=0.000 n=9+10)
AnchoredLongMatch-12                272ns ± 0%     268ns ± 1%   -1.46%  (p=0.000 n=8+10)
OnePassShortA-12                    615ns ± 0%     614ns ± 0%     ~     (p=0.094 n=10+6)
NotOnePassShortA-12                 549ns ± 0%     552ns ± 0%   +0.52%  (p=0.000 n=9+10)
OnePassShortB-12                    494ns ± 0%     494ns ± 0%     ~     (p=0.247 n=8+9)
NotOnePassShortB-12                 412ns ± 1%     411ns ± 0%     ~     (p=0.625 n=10+9)
OnePassLongPrefix-12                108ns ± 0%     109ns ± 0%   +0.93%  (p=0.000 n=10+8)
OnePassLongNotPrefix-12             402ns ± 0%     403ns ± 0%   +0.14%  (p=0.041 n=8+9)
MatchParallelShared-12             38.6ns ± 2%    38.9ns ± 1%     ~     (p=0.172 n=9+10)
MatchParallelCopied-12             39.4ns ± 7%    39.2ns ± 1%     ~     (p=0.423 n=10+10)
QuoteMetaAll-12                    94.9ns ± 0%    94.5ns ± 0%   -0.42%  (p=0.000 n=9+10)
QuoteMetaNone-12                   52.7ns ± 0%    52.7ns ± 0%     ~     (all equal)
Match/Easy0/32-12                  72.1ns ± 0%    72.2ns ± 0%     ~     (p=0.435 n=9+8)
Match/Easy0/1K-12                   298ns ± 0%     296ns ± 1%   -1.01%  (p=0.000 n=8+10)
Match/Easy0/32K-12                 4.64µs ± 1%    4.57µs ± 3%   -1.39%  (p=0.030 n=10+10)
Match/Easy0/1M-12                   234µs ± 0%     234µs ± 0%     ~     (p=0.971 n=10+10)
Match/Easy0/32M-12                 7.95ms ± 0%    7.96ms ± 0%     ~     (p=0.278 n=9+10)
Match/Easy0i/32-12                 1.10µs ± 0%    1.09µs ± 0%   -0.29%  (p=0.000 n=9+8)
Match/Easy0i/1K-12                 31.8µs ± 1%    31.7µs ± 0%     ~     (p=0.704 n=10+9)
Match/Easy0i/32K-12                1.62ms ± 1%    1.61ms ± 0%   -1.12%  (p=0.000 n=10+8)
Match/Easy0i/1M-12                 51.8ms ± 0%    51.4ms ± 0%   -0.84%  (p=0.000 n=8+8)
Match/Easy0i/32M-12                 1.65s ± 0%     1.65s ± 0%   -0.46%  (p=0.000 n=9+9)
Match/Easy1/32-12                  67.7ns ± 1%    67.6ns ± 1%     ~     (p=0.723 n=10+10)
Match/Easy1/1K-12                   873ns ± 0%     873ns ± 2%     ~     (p=0.345 n=10+9)
Match/Easy1/32K-12                 39.4µs ± 0%    39.7µs ± 1%   +0.66%  (p=0.000 n=10+10)
Match/Easy1/1M-12                  1.39ms ± 0%    1.41ms ± 1%   +1.10%  (p=0.000 n=10+10)
Match/Easy1/32M-12                 44.3ms ± 0%    44.9ms ± 1%   +1.18%  (p=0.000 n=10+10)
Match/Medium/32-12                 1.04µs ± 0%    1.04µs ± 0%   -0.58%  (p=0.000 n=9+9)
Match/Medium/1K-12                 31.4µs ± 0%    31.2µs ± 0%   -0.62%  (p=0.000 n=8+8)
Match/Medium/32K-12                1.45ms ± 0%    1.45ms ± 1%     ~     (p=0.356 n=9+10)
Match/Medium/1M-12                 46.4ms ± 0%    46.4ms ± 0%     ~     (p=0.142 n=8+6)
Match/Medium/32M-12                 1.49s ± 1%     1.49s ± 1%     ~     (p=0.739 n=10+10)
Match/Hard/32-12                   1.48µs ± 0%    1.47µs ± 0%   -0.53%  (p=0.000 n=9+9)
Match/Hard/1K-12                   45.0µs ± 1%    44.5µs ± 1%   -1.06%  (p=0.000 n=10+10)
Match/Hard/32K-12                  2.24ms ± 0%    2.09ms ± 0%   -6.56%  (p=0.000 n=8+8)
Match/Hard/1M-12                   71.6ms ± 0%    67.8ms ± 5%   -5.36%  (p=0.000 n=7+10)
Match/Hard/32M-12                   2.29s ± 0%     2.17s ± 5%   -5.40%  (p=0.000 n=9+10)
Match/Hard1/32-12                  7.89µs ± 0%    7.89µs ± 0%     ~     (p=0.053 n=9+9)
Match/Hard1/1K-12                   244µs ± 0%     246µs ± 0%   +0.71%  (p=0.000 n=10+9)
Match/Hard1/32K-12                 10.3ms ± 0%     8.9ms ± 0%  -13.76%  (p=0.000 n=10+9)
Match/Hard1/1M-12                   331ms ± 0%     286ms ± 0%  -13.72%  (p=0.000 n=9+9)
Match/Hard1/32M-12                  10.6s ± 0%      9.2s ± 0%  -13.72%  (p=0.000 n=10+9)
Match_onepass_regex/32-12           830ns ± 0%     825ns ± 0%   -0.57%  (p=0.000 n=9+8)
Match_onepass_regex/1K-12          28.7µs ± 1%    28.7µs ± 1%   -0.22%  (p=0.040 n=9+9)
Match_onepass_regex/32K-12          949µs ± 0%     950µs ± 1%     ~     (p=0.236 n=8+9)
Match_onepass_regex/1M-12          30.4ms ± 0%    30.4ms ± 0%     ~     (p=0.059 n=8+9)
Match_onepass_regex/32M-12          973ms ± 0%     974ms ± 1%     ~     (p=0.258 n=9+9)
CompileOnepass-12                  4.64µs ± 0%    4.60µs ± 0%   -0.90%  (p=0.000 n=10+8)
[Geo mean]                         23.3µs         23.1µs        -1.16%

https://perf.golang.org/search?q=upload:20181004.3

Change-Id: I46f3d52ce89c8cd992cf554473c27af81fd81bfd
Reviewed-on: https://go-review.googlesource.com/c/139781
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-10-12 17:48:36 +00:00
Russ Cox
60b2971180 regexp: split one-pass execution out of machine struct
This allows the one-pass executions to have their
own pool of (much smaller) allocated structures.
A step toward eliminating the per-Regexp machine cache.

Not much effect on benchmarks, since there are no
optimizations here, and pools are a tiny bit slower than a
locked data structure for single-threaded code.

name                             old time/op    new time/op    delta
Find-12                             254ns ± 0%     252ns ± 0%  -0.94%  (p=0.000 n=9+10)
FindAllNoMatches-12                 135ns ± 0%     134ns ± 1%  -0.49%  (p=0.002 n=9+9)
FindString-12                       247ns ± 0%     246ns ± 0%  -0.24%  (p=0.003 n=8+10)
FindSubmatch-12                     334ns ± 0%     333ns ± 2%    ~     (p=0.283 n=10+10)
FindStringSubmatch-12               321ns ± 0%     320ns ± 0%  -0.51%  (p=0.000 n=9+10)
Literal-12                         92.2ns ± 0%    91.1ns ± 0%  -1.25%  (p=0.000 n=9+10)
NotLiteral-12                      1.47µs ± 0%    1.45µs ± 0%  -0.99%  (p=0.000 n=9+10)
MatchClass-12                      2.17µs ± 0%    2.19µs ± 0%  +0.84%  (p=0.000 n=7+9)
MatchClass_InRange-12              2.13µs ± 0%    2.09µs ± 0%  -1.70%  (p=0.000 n=10+10)
ReplaceAll-12                      1.39µs ± 0%    1.39µs ± 0%  +0.51%  (p=0.000 n=10+10)
AnchoredLiteralShortNonMatch-12    83.2ns ± 0%    82.4ns ± 0%  -0.96%  (p=0.000 n=8+8)
AnchoredLiteralLongNonMatch-12      105ns ± 0%     106ns ± 1%    ~     (p=0.087 n=10+10)
AnchoredShortMatch-12               131ns ± 0%     130ns ± 0%  -0.76%  (p=0.000 n=10+9)
AnchoredLongMatch-12                267ns ± 0%     272ns ± 0%  +2.01%  (p=0.000 n=10+8)
OnePassShortA-12                    611ns ± 0%     615ns ± 0%  +0.61%  (p=0.000 n=9+10)
NotOnePassShortA-12                 552ns ± 0%     549ns ± 0%  -0.46%  (p=0.000 n=8+9)
OnePassShortB-12                    491ns ± 0%     494ns ± 0%  +0.61%  (p=0.000 n=8+8)
NotOnePassShortB-12                 412ns ± 0%     412ns ± 1%    ~     (p=0.151 n=9+10)
OnePassLongPrefix-12                112ns ± 0%     108ns ± 0%  -3.57%  (p=0.000 n=10+10)
OnePassLongNotPrefix-12             410ns ± 0%     402ns ± 0%  -1.95%  (p=0.000 n=9+8)
MatchParallelShared-12             38.8ns ± 1%    38.6ns ± 2%    ~     (p=0.536 n=10+9)
MatchParallelCopied-12             39.2ns ± 3%    39.4ns ± 7%    ~     (p=0.986 n=10+10)
QuoteMetaAll-12                    94.6ns ± 0%    94.9ns ± 0%  +0.29%  (p=0.001 n=8+9)
QuoteMetaNone-12                   52.7ns ± 0%    52.7ns ± 0%    ~     (all equal)
Match/Easy0/32-12                  72.9ns ± 0%    72.1ns ± 0%  -1.07%  (p=0.000 n=9+9)
Match/Easy0/1K-12                   298ns ± 0%     298ns ± 0%    ~     (p=0.140 n=6+8)
Match/Easy0/32K-12                 4.60µs ± 2%    4.64µs ± 1%    ~     (p=0.171 n=10+10)
Match/Easy0/1M-12                   235µs ± 0%     234µs ± 0%  -0.14%  (p=0.004 n=10+10)
Match/Easy0/32M-12                 7.96ms ± 0%    7.95ms ± 0%  -0.12%  (p=0.043 n=10+9)
Match/Easy0i/32-12                 1.09µs ± 0%    1.10µs ± 0%  +0.15%  (p=0.000 n=8+9)
Match/Easy0i/1K-12                 31.7µs ± 0%    31.8µs ± 1%    ~     (p=0.905 n=9+10)
Match/Easy0i/32K-12                1.61ms ± 0%    1.62ms ± 1%  +1.12%  (p=0.000 n=9+10)
Match/Easy0i/1M-12                 51.4ms ± 0%    51.8ms ± 0%  +0.85%  (p=0.000 n=8+8)
Match/Easy0i/32M-12                 1.65s ± 1%     1.65s ± 0%    ~     (p=0.113 n=9+9)
Match/Easy1/32-12                  67.9ns ± 0%    67.7ns ± 1%    ~     (p=0.232 n=8+10)
Match/Easy1/1K-12                   884ns ± 0%     873ns ± 0%  -1.29%  (p=0.000 n=9+10)
Match/Easy1/32K-12                 39.2µs ± 0%    39.4µs ± 0%  +0.50%  (p=0.000 n=9+10)
Match/Easy1/1M-12                  1.39ms ± 0%    1.39ms ± 0%  +0.29%  (p=0.000 n=9+10)
Match/Easy1/32M-12                 44.2ms ± 1%    44.3ms ± 0%  +0.21%  (p=0.029 n=10+10)
Match/Medium/32-12                 1.05µs ± 0%    1.04µs ± 0%  -0.27%  (p=0.001 n=8+9)
Match/Medium/1K-12                 31.3µs ± 0%    31.4µs ± 0%  +0.39%  (p=0.000 n=9+8)
Match/Medium/32K-12                1.45ms ± 0%    1.45ms ± 0%  +0.33%  (p=0.000 n=8+9)
Match/Medium/1M-12                 46.2ms ± 0%    46.4ms ± 0%  +0.35%  (p=0.000 n=9+8)
Match/Medium/32M-12                 1.48s ± 0%     1.49s ± 1%  +0.70%  (p=0.000 n=8+10)
Match/Hard/32-12                   1.49µs ± 0%    1.48µs ± 0%  -0.43%  (p=0.000 n=10+9)
Match/Hard/1K-12                   45.1µs ± 1%    45.0µs ± 1%    ~     (p=0.393 n=10+10)
Match/Hard/32K-12                  2.18ms ± 1%    2.24ms ± 0%  +2.71%  (p=0.000 n=9+8)
Match/Hard/1M-12                   69.7ms ± 1%    71.6ms ± 0%  +2.76%  (p=0.000 n=9+7)
Match/Hard/32M-12                   2.23s ± 1%     2.29s ± 0%  +2.65%  (p=0.000 n=9+9)
Match/Hard1/32-12                  7.89µs ± 0%    7.89µs ± 0%    ~     (p=0.286 n=9+9)
Match/Hard1/1K-12                   244µs ± 0%     244µs ± 0%    ~     (p=0.905 n=9+10)
Match/Hard1/32K-12                 10.3ms ± 0%    10.3ms ± 0%    ~     (p=0.796 n=10+10)
Match/Hard1/1M-12                   331ms ± 0%     331ms ± 0%    ~     (p=0.167 n=8+9)
Match/Hard1/32M-12                  10.6s ± 0%     10.6s ± 0%    ~     (p=0.315 n=8+10)
Match_onepass_regex/32-12           812ns ± 0%     830ns ± 0%  +2.19%  (p=0.000 n=10+9)
Match_onepass_regex/1K-12          28.5µs ± 0%    28.7µs ± 1%  +0.97%  (p=0.000 n=10+9)
Match_onepass_regex/32K-12          936µs ± 0%     949µs ± 0%  +1.43%  (p=0.000 n=10+8)
Match_onepass_regex/1M-12          30.2ms ± 0%    30.4ms ± 0%  +0.62%  (p=0.000 n=10+8)
Match_onepass_regex/32M-12          970ms ± 0%     973ms ± 0%  +0.35%  (p=0.000 n=10+9)
CompileOnepass-12                  4.63µs ± 1%    4.64µs ± 0%    ~     (p=0.060 n=10+10)
[Geo mean]                         23.3µs         23.3µs       +0.12%

https://perf.golang.org/search?q=upload:20181004.2

Change-Id: Iff9e9f9d4a4698162126a2f300e8ed1b1a39361e
Reviewed-on: https://go-review.googlesource.com/c/139780
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-10-12 17:48:35 +00:00
Russ Cox
2d4346b319 regexp: split bit-state execution out of machine struct
This allows the bit-state executions to have their
own pool of allocated structures. A step toward
eliminating the per-Regexp machine cache.

Note especially the -92% on MatchParallelShared.
This is real but not a complete story: the other
execution engines still need to be de-shared,
but the benchmark was only using bit-state.

The tiny slowdowns in unrelated code are noise.

name                             old time/op    new time/op    delta
Find-12                             264ns ± 3%     254ns ± 0%   -3.86%  (p=0.000 n=10+9)
FindAllNoMatches-12                 140ns ± 2%     135ns ± 0%   -3.91%  (p=0.000 n=10+9)
FindString-12                       256ns ± 0%     247ns ± 0%   -3.52%  (p=0.000 n=8+8)
FindSubmatch-12                     339ns ± 1%     334ns ± 0%   -1.41%  (p=0.000 n=9+10)
FindStringSubmatch-12               322ns ± 0%     321ns ± 0%   -0.21%  (p=0.005 n=8+9)
Literal-12                          100ns ± 2%      92ns ± 0%   -8.10%  (p=0.000 n=10+9)
NotLiteral-12                      1.50µs ± 0%    1.47µs ± 0%   -1.91%  (p=0.000 n=8+9)
MatchClass-12                      2.18µs ± 0%    2.17µs ± 0%   -0.20%  (p=0.001 n=10+7)
MatchClass_InRange-12              2.12µs ± 0%    2.13µs ± 0%   +0.23%  (p=0.000 n=10+10)
ReplaceAll-12                      1.41µs ± 0%    1.39µs ± 0%   -1.30%  (p=0.000 n=7+10)
AnchoredLiteralShortNonMatch-12    89.8ns ± 0%    83.2ns ± 0%   -7.35%  (p=0.000 n=8+8)
AnchoredLiteralLongNonMatch-12      105ns ± 3%     105ns ± 0%     ~     (p=0.186 n=10+10)
AnchoredShortMatch-12               141ns ± 0%     131ns ± 0%   -7.09%  (p=0.000 n=9+10)
AnchoredLongMatch-12                276ns ± 4%     267ns ± 0%   -3.23%  (p=0.000 n=10+10)
OnePassShortA-12                    620ns ± 0%     611ns ± 0%   -1.39%  (p=0.000 n=10+9)
NotOnePassShortA-12                 575ns ± 3%     552ns ± 0%   -3.97%  (p=0.000 n=10+8)
OnePassShortB-12                    493ns ± 0%     491ns ± 0%   -0.33%  (p=0.000 n=8+8)
NotOnePassShortB-12                 423ns ± 0%     412ns ± 0%   -2.60%  (p=0.000 n=8+9)
OnePassLongPrefix-12                112ns ± 0%     112ns ± 0%     ~     (all equal)
OnePassLongNotPrefix-12             405ns ± 0%     410ns ± 0%   +1.23%  (p=0.000 n=8+9)
MatchParallelShared-12              501ns ± 1%      39ns ± 1%  -92.27%  (p=0.000 n=10+10)
MatchParallelCopied-12             39.1ns ± 0%    39.2ns ± 3%     ~     (p=0.785 n=6+10)
QuoteMetaAll-12                    94.6ns ± 0%    94.6ns ± 0%     ~     (p=0.439 n=10+8)
QuoteMetaNone-12                   52.7ns ± 0%    52.7ns ± 0%     ~     (all equal)
Match/Easy0/32-12                  79.1ns ± 0%    72.9ns ± 0%   -7.85%  (p=0.000 n=9+9)
Match/Easy0/1K-12                   307ns ± 1%     298ns ± 0%   -2.99%  (p=0.000 n=10+6)
Match/Easy0/32K-12                 4.65µs ± 2%    4.60µs ± 2%     ~     (p=0.159 n=10+10)
Match/Easy0/1M-12                   234µs ± 0%     235µs ± 0%   +0.17%  (p=0.003 n=10+10)
Match/Easy0/32M-12                 7.98ms ± 1%    7.96ms ± 0%     ~     (p=0.278 n=9+10)
Match/Easy0i/32-12                 1.13µs ± 1%    1.09µs ± 0%   -3.24%  (p=0.000 n=9+8)
Match/Easy0i/1K-12                 32.5µs ± 0%    31.7µs ± 0%   -2.66%  (p=0.000 n=9+9)
Match/Easy0i/32K-12                1.59ms ± 0%    1.61ms ± 0%   +0.75%  (p=0.000 n=9+9)
Match/Easy0i/1M-12                 51.0ms ± 0%    51.4ms ± 0%   +0.77%  (p=0.000 n=10+8)
Match/Easy0i/32M-12                 1.63s ± 0%     1.65s ± 1%   +1.24%  (p=0.000 n=7+9)
Match/Easy1/32-12                  75.1ns ± 1%    67.9ns ± 0%   -9.54%  (p=0.000 n=8+8)
Match/Easy1/1K-12                   861ns ± 0%     884ns ± 0%   +2.71%  (p=0.000 n=8+9)
Match/Easy1/32K-12                 39.2µs ± 1%    39.2µs ± 0%     ~     (p=0.090 n=10+9)
Match/Easy1/1M-12                  1.38ms ± 0%    1.39ms ± 0%     ~     (p=0.095 n=10+9)
Match/Easy1/32M-12                 44.2ms ± 1%    44.2ms ± 1%     ~     (p=0.218 n=10+10)
Match/Medium/32-12                 1.04µs ± 1%    1.05µs ± 0%   +1.05%  (p=0.000 n=9+8)
Match/Medium/1K-12                 31.3µs ± 0%    31.3µs ± 0%   -0.14%  (p=0.004 n=9+9)
Match/Medium/32K-12                1.44ms ± 0%    1.45ms ± 0%   +0.18%  (p=0.001 n=8+8)
Match/Medium/1M-12                 46.1ms ± 0%    46.2ms ± 0%   +0.13%  (p=0.003 n=6+9)
Match/Medium/32M-12                 1.48s ± 0%     1.48s ± 0%   +0.20%  (p=0.002 n=9+8)
Match/Hard/32-12                   1.54µs ± 1%    1.49µs ± 0%   -3.60%  (p=0.000 n=9+10)
Match/Hard/1K-12                   46.4µs ± 1%    45.1µs ± 1%   -2.78%  (p=0.000 n=9+10)
Match/Hard/32K-12                  2.19ms ± 0%    2.18ms ± 1%   -0.51%  (p=0.006 n=8+9)
Match/Hard/1M-12                   70.1ms ± 0%    69.7ms ± 1%   -0.52%  (p=0.006 n=8+9)
Match/Hard/32M-12                   2.24s ± 0%     2.23s ± 1%   -0.42%  (p=0.046 n=8+9)
Match/Hard1/32-12                  8.17µs ± 1%    7.89µs ± 0%   -3.42%  (p=0.000 n=8+9)
Match/Hard1/1K-12                   254µs ± 2%     244µs ± 0%   -3.91%  (p=0.000 n=9+9)
Match/Hard1/32K-12                 9.58ms ± 1%   10.35ms ± 0%   +8.00%  (p=0.000 n=10+10)
Match/Hard1/1M-12                   306ms ± 1%     331ms ± 0%   +8.27%  (p=0.000 n=9+8)
Match/Hard1/32M-12                  9.79s ± 1%    10.60s ± 0%   +8.29%  (p=0.000 n=9+8)
Match_onepass_regex/32-12           808ns ± 0%     812ns ± 0%   +0.47%  (p=0.000 n=8+10)
Match_onepass_regex/1K-12          27.8µs ± 0%    28.5µs ± 0%   +2.32%  (p=0.000 n=8+10)
Match_onepass_regex/32K-12          925µs ± 0%     936µs ± 0%   +1.24%  (p=0.000 n=9+10)
Match_onepass_regex/1M-12          29.5ms ± 0%    30.2ms ± 0%   +2.38%  (p=0.000 n=10+10)
Match_onepass_regex/32M-12          945ms ± 0%     970ms ± 0%   +2.60%  (p=0.000 n=9+10)
CompileOnepass-12                  4.67µs ± 0%    4.63µs ± 1%   -0.84%  (p=0.000 n=10+10)
[Geo mean]                         24.5µs         23.3µs        -5.04%

https://perf.golang.org/search?q=upload:20181004.1

Change-Id: Idbc2b76223718265657819ff38be2d9aba1c54b4
Reviewed-on: https://go-review.googlesource.com/c/139779
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2018-10-12 17:48:34 +00:00
Russ Cox
8e0aea162b testing: implement -benchtime=100x
When running benchmarks with profilers and trying to
compare one run against another, it is very useful to be
able to force each run to execute exactly the same number
of iterations.

Discussion on the proposal issue #24735 led to the decision
to overload -benchtime, so that instead of saying
-benchtime 10s to run a benchmark for 10 seconds,
you say -benchtime 100x to run a benchmark 100 times.

Fixes #24735.

Change-Id: Id17c5bd18bd09987bb48ed12420d61ae9e200fd7
Reviewed-on: https://go-review.googlesource.com/c/139258
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-10-12 17:48:31 +00:00
Robert Griesemer
56131cbd1d go/types: remove a test case and update comment
The original need for the extra test case and issue was eliminated
by https://golang.org/cl/116815 which introduced systematic cycle
detection. Now that we correctly report the cycle, we can't say much
about the invalid cast anyway (the type is invalid due to the cycle).

A more sophisticated approach would be able to tell the size of
a function type independent of the details of that type, but the
type-checker is not set up for this kind of lazy type-checking.

Fixes #23127.

Change-Id: Ia8479e66baf630ce96f6f36770c8e1c810c59ddc
Reviewed-on: https://go-review.googlesource.com/c/141640
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Alan Donovan <adonovan@google.com>
2018-10-12 16:57:39 +00:00
Martin Möhrmann
4fb8b1de3c internal/cpu: use 'off' for disabling cpu capabilities instead of '0'
Updates #27218

Change-Id: I4ce20376fd601b5f958d79014af7eaf89e9de613
Reviewed-on: https://go-review.googlesource.com/c/141818
Run-TryBot: Martin Möhrmann <moehrmann@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-10-12 16:44:26 +00:00
Tobias Klauser
d82e51a119 internal/poll: add FD.Fsync on aix
Follow-up for CL 138717. This fixes the build of the os package on
aix.

Change-Id: I879b9360e71837ab622ae3a7b6144782cf5a9ce7
Reviewed-on: https://go-review.googlesource.com/c/141797
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-10-12 16:10:54 +00:00
Martin Möhrmann
a5248acd91 internal/cpu: enable support for GODEBUGCPU in non-experimental builds
Enabling GODEBUGCPU without the need to set GOEXPERIMENT=debugcpu  enables
trybots and builders to run tests for GODEBUGCPU features in upcoming CLs
that will implement the new syntax and features for non-experimental
GODEBUGCPU support from proposal golang.org/issue/27218.

Updates #27218

Change-Id: Icc69e51e736711a86b02b46bd441ffc28423beba
Reviewed-on: https://go-review.googlesource.com/c/141817
Run-TryBot: Martin Möhrmann <moehrmann@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-10-12 15:40:45 +00:00
Brad Fitzpatrick
da6c168378 net/http: flesh out Transport's HTTP/1 CONNECT+bidi support to match HTTP/2
Fixes #17227

Change-Id: I0f8964593d69623b85d5759f6276063ee62b2915
Reviewed-on: https://go-review.googlesource.com/c/123156
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-10-12 15:00:32 +00:00
Yuval Pavel Zholkover
e19f575464 syscall: correctly pad with NUL in FreeBSD convertFromDirents11
We weren't writing a terminating NUL after dstDirent.Namlen bytes of dstDirent.Name.
And we weren't filling the possible additional bytes until dstDirent.Reclen.

Fixes #28131

Change-Id: Id691c25225795c0dbb0d7004bfca7bb7fc706de9
Reviewed-on: https://go-review.googlesource.com/c/141297
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-10-12 14:55:06 +00:00
Mihai Todor
1f95e0a9d9 encoding/base64: fix typo in decodeQuantum docs
Change-Id: I643540bcea574d8a70b79237d97097dcc7368766
GitHub-Last-Rev: e2be58d1ab
GitHub-Pull-Request: golang/go#28125
Reviewed-on: https://go-review.googlesource.com/c/141119
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-10-12 14:36:03 +00:00
Elias Naur
93cf82f08a os: make UserHomeDir return "/" on iOS
The UserHomeDir test succeeds on the builder, but not when run
manually where HOME is set to the host $HOME.

Change-Id: I1db0f608b04b311b53cc0c8160a3778caaf542f6
Reviewed-on: https://go-review.googlesource.com/c/141798
Run-TryBot: Elias Naur <elias.naur@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-10-12 14:25:13 +00:00
Matthew Dempsky
a0d6420d8b cmd/compile/internal/gc: remove OCMPIFACE/OCMPSTR placeholders
Change-Id: If05f6146a1fd97f61fc71629c5c29df43220d0c8
Reviewed-on: https://go-review.googlesource.com/c/141638
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-10-11 21:18:44 +00:00
Matthew Dempsky
28fbbf4111 cmd/compile/internal/gc: remove OCMPIFACE and OCMPSTR
Interface and string comparisons don't need separate Ops any more than
struct or array comparisons do.

Removing them requires shuffling some code around in walk (and a
little in order), but overall allows simplifying things a bit.

Passes toolstash-check.

Change-Id: I084b8a6c089b768dc76d220379f4daed8a35db15
Reviewed-on: https://go-review.googlesource.com/c/141637
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2018-10-11 21:18:33 +00:00
Robert Griesemer
f64fd66f24 go/scanner: don't return token.INVALID for ".." sequence
Per the spec, "...the next token is the longest sequence of characters
that form a valid token." Thus, encountering a ".." sequence should
return two token.PERIOD tokens rather than a single token.ILLEGAL.

Fixes #28112.

Change-Id: Iba5da841f40036e53f48f9be23f933f362e67f5e
Reviewed-on: https://go-review.googlesource.com/c/141337
Reviewed-by: Dmitri Shuralyov <dmitshur@golang.org>
2018-10-11 20:26:55 +00:00
Ian Davis
7fb60eb1a2 cmd/vet: detect non-pointer arguments for unmarshal and decode
Checks usage of Unmarshal and Decode functions in json, gob and
xml packages to detect attempts to decode into non-pointer types.

Fixes #27564

Change-Id: I07bbd5be82d61834ffde9af9937329d7fb1f05d0
Reviewed-on: https://go-review.googlesource.com/c/139997
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Alan Donovan <adonovan@google.com>
2018-10-11 18:45:18 +00:00
Robert Griesemer
76f578459a go/types: use correct receiver types for embedded interface methods
Interface methods don't declare a receiver (it's implicit), but after
type-checking the respective *types.Func objects are marked as methods
by having a receiver. For interface methods, the receiver base type used
to be the interface that declared the method in the first place, even if
the method also appeared in other interfaces via embedding. A change in
the computation of method sets for interfaces for Go1.10 changed that
inadvertently, with the consequence that sometimes a method's receiver
type ended up being an interface into which the method was embedded.
The exact behavior also depended on file type-checking order, and because
files are sometimes sorted by name, the behavior depended on file names.

This didn't matter for type-checking (the typechecker doesn't need the
receiver), but it matters for clients, and for printing of methods.

This change fixes interface method receivers at the end of type-checking
when we have all relevant information.

Fixes #28005.

Change-Id: I96c120fb0e517d7f8a14b8530f0273674569d5ea
Reviewed-on: https://go-review.googlesource.com/c/141358
Reviewed-by: Alan Donovan <adonovan@google.com>
2018-10-11 18:17:34 +00:00
Russ Cox
872a547957 regexp: fix BenchmarkMatch_onepass_regex
This benchmark - in contrast to all other benchmarks - was
running the regexp match on 1-byte substrings of the input
instead of the entire input. Worse, it was doing so by preallocating
a slice of slices of every 1-byte substring. Needless to say,
this does not accurately reflect what happens when the regexp
matcher is given a large input.

Change-Id: Icd5b95f0e43f554a6b93164916745941366e03d6
Reviewed-on: https://go-review.googlesource.com/c/139778
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2018-10-11 18:01:17 +00:00
Russ Cox
e2d70b8b4b regexp: simplify BenchmarkCompileOnepass
One benchmark is fine.
Having one per test case is overkill.

Change-Id: Id4ce789484dab1e79026bdd23cbcd63b2eaceb3f
Reviewed-on: https://go-review.googlesource.com/c/139777
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2018-10-11 18:01:06 +00:00
Florian
689321e108 doc: add link to the Go Discord forum
I've linked the  gophers discord. It's a well administered discord which already got many members, but it was never officially linked. For many people it's a quality proof if a discord is linked on the official page. I think there are much more people out there, who would prefer to use discord instead of slack or irc.

The discord already got many users without even being promoted, so it's very likely there are many people who are interested in a discord, but they don't want to use unofficial discords. This discord shouldn't be seen as a competitor for the slack, it's a platform for those, who don't want to use slack.

Change-Id: Ib1ee7173f394b810f5cccf67b498485ecbf8a7db
GitHub-Last-Rev: 286ebad994
GitHub-Pull-Request: golang/go#24176
Reviewed-on: https://go-review.googlesource.com/c/97718
Reviewed-by: Andrew Bonventre <andybons@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-10-11 16:31:24 +00:00
Clément Chigot
835f983da6 os: add AIX operating system
This commit adds AIX operating system to os package for ppc64
architecture.

Updates: #25893

Change-Id: Ieb9a2b3ac5b9abd3b5ab68eb732c17b6256d624d
Reviewed-on: https://go-review.googlesource.com/c/138725
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2018-10-11 15:41:04 +00:00
David Chase
69c5830c2b cmd/compile: repair display of values & blocks in prog column
This restores the printing of vXX and bYY in the left-hand
edge of the last column of ssa.html, where the generated
progs appear.

Change-Id: I81ab9b2fa5ae28e6e5de1b77665cfbed8d14e000
Reviewed-on: https://go-review.googlesource.com/c/141277
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Yury Smolsky <yury@smolsky.by>
2018-10-11 15:29:00 +00:00
Ben Shi
bac6a2925c test/codegen: add more arm64 test cases
This CL adds 3 combined load test cases for arm64.

Change-Id: I2c67308c40fd8a18f9f2d16c6d12911dcdc583e2
Reviewed-on: https://go-review.googlesource.com/c/140700
Run-TryBot: Ben Shi <powerman1st@163.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-10-11 15:14:06 +00:00
Clément Chigot
1d0e94b1e1 path/filepath: add AIX operating system
This commit adds AIX operating system to path/filepath package
for ppc64 architecture.

Updates: #25893

Change-Id: Iea551236d334705a58a446c8992b20adcfe4159b
Reviewed-on: https://go-review.googlesource.com/c/138726
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-10-11 14:46:37 +00:00
Carlos Eduardo Seo
23578f9d00 cmd/compile: intrinsify TrailingZeros16, OnesCount{8,16} for ppc64x
This change implements TrailingZeros16, OnesCount8 and OnesCount16
as intrinsics for ppc64x.

benchmark                       old ns/op     new ns/op     delta
BenchmarkTrailingZeros16-40     2.16          1.61          -25.46%

benchmark                   old ns/op     new ns/op     delta
BenchmarkOnesCount-40       0.71          0.71          +0.00%
BenchmarkOnesCount8-40      0.93          0.69          -25.81%
BenchmarkOnesCount16-40     1.54          0.75          -51.30%
BenchmarkOnesCount32-40     0.75          0.74          -1.33%
BenchmarkOnesCount64-40     0.71          0.71          +0.00%

Change-Id: I010fa9c0ef596a09362870d81193c633e70da637
Reviewed-on: https://go-review.googlesource.com/c/139137
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>
2018-10-11 13:21:50 +00:00
LotusFenn
c96c2a39bb bytes: vary the input alignment to Compare argument in compare_test.go
Currently there are no tests that vary the alignment of Compare arguments.
Since Compare is written in assembly on most platforms (in internal/bytealg)
we should be testing different input alignments. This change modifies TestCompare
to vary the alignment of the second argument of Compare.

Updates #26129

Change-Id: I4c30a5adf96a41225df748675f4e9beea413b35c
Reviewed-on: https://go-review.googlesource.com/c/122536
Reviewed-by: Lotus Fenn <fenn.lotus@gmail.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2018-10-11 04:45:18 +00:00
Rob Pike
9a9dc36f97 text/template: explain that integer constants can overflow
This behavior is the same as in Go: constants can be coerced to int
and whether overflow occurs depends on how big an int is, but
this surprises people sometimes, so document it again here.

Fixes #25833.

Change-Id: I557995f1a1e8e871b21004953923d16f36cb9037
Reviewed-on: https://go-review.googlesource.com/c/141378
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-10-11 02:32:47 +00:00
Rob Pike
daf6f25433 unsafe: document that Alignof, Offsetof, and Sizeof return a constant
Nothing is changing but the documentation, which did not mention
this property of these functions.

Fixes #27587.

Change-Id: I75bcee4a1dd9ec8cd82826c9a6e02ba7d599f719
Reviewed-on: https://go-review.googlesource.com/c/141377
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2018-10-11 02:32:20 +00:00