Commits · 3c023f75a62f903273c688432f95e77fc945b6fb · Kirill Smelkov / go

28 Feb, 2017 23 commits

strings: fix handling of invalid UTF-8 sequences in Map · 3c023f75

Martin Möhrmann authored Feb 28, 2017

The new Map implementation introduced in golang.org/cl/33201
did not differentiate if an invalid UTF-8 sequence was decoded
or the RuneError rune. It would therefore always advance by
3 bytes (which is the length of the RuneError rune) instead
of 1 for an invalid sequences. This cl adds a check to correctly
determine the length of bytes needed to advance to the next rune.

Fixes #19330.

Change-Id: I1e7f9333f3ef6068ffc64015bb0a9f32b0b7111d
Reviewed-on: https://go-review.googlesource.com/37597
Run-TryBot: Martin Möhrmann <moehrmann@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Joe Tsai <thebrokentoaster@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

3c023f75

cmd/compile: simplify load+op rules · 0fe58bf6

Keith Randall authored Feb 28, 2017

There's no need to use @block rules, as canMergeLoad makes sure that
the load and op are already in the same block.
With no @block needed, we also don't need to set the type explicitly.
It can just be inherited from the op being rewritten.

Noticed while working on #19284.

Change-Id: Ied8bcc8058260118ff7e166093112e29107bcb7e
Reviewed-on: https://go-review.googlesource.com/37585
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: Ilya Tocar <ilya.tocar@intel.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

0fe58bf6

go/types: implement SizesFor convenience function · 45055f21

Robert Griesemer authored Feb 28, 2017

SizesFor returns a Sizes implementation for a supported architecture.
Use functionality in srcimporter.

Change-Id: I197e641b419c678030dfaab5c5b8c569fd0410f3
Reviewed-on: https://go-review.googlesource.com/37583
Run-TryBot: Robert Griesemer <gri@golang.org>
Reviewed-by: Alan Donovan <adonovan@google.com>

45055f21

math/bits: faster LeadingZeros and Len functions · 83bc4a2f

Robert Griesemer authored Feb 28, 2017

benchmark old ns/op new ns/op delta
BenchmarkLeadingZeros-8 8.43 3.10 -63.23%
BenchmarkLeadingZeros8-8 8.13 1.33 -83.64%
BenchmarkLeadingZeros16-8 7.34 2.07 -71.80%
BenchmarkLeadingZeros32-8 7.99 2.87 -64.08%
BenchmarkLeadingZeros64-8 8.13 2.96 -63.59%

Measured on 2.3 GHz Intel Core i7 running macOS 10.12.3.

Change-Id: Id343531b408d42ac45f10c76f60e85bdb977f91e
Reviewed-on: https://go-review.googlesource.com/37582Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

83bc4a2f

math/bits: faster TrailingZeroes8 · 9515cb51

Robert Griesemer authored Feb 28, 2017

For sizes > 8, the existing code is faster.

benchmark old ns/op new ns/op delta
BenchmarkTrailingZeros8-8 1.95 1.29 -33.85%

Measured on 2.3 GHz Intel Core i7 running macOS 10.12.3.

Change-Id: I6f3a33ec633a2c544ec29693c141f2f99335c745
Reviewed-on: https://go-review.googlesource.com/37581Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

9515cb51

math/bits: faster OnesCount using table lookups for sizes 8,16,32 · d7a659b1

Robert Griesemer authored Feb 28, 2017

For uint64, the existing algorithm is faster.

benchmark old ns/op new ns/op delta
BenchmarkOnesCount8-8 1.95 0.97 -50.26%
BenchmarkOnesCount16-8 2.54 1.39 -45.28%
BenchmarkOnesCount32-8 2.61 1.96 -24.90%

Measured on 2.3 GHz Intel Core i7 running macOS 10.12.3.

Change-Id: I6cc42882fef3d24694720464039161e339a9ae99
Reviewed-on: https://go-review.googlesource.com/37580Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

d7a659b1

runtime: evacuate old map buckets more consistently · 064e44f2

Josh Bleecher Snyder authored Feb 14, 2017

During map growth, buckets are evacuated in two ways.
When a value is altered, its containing bucket is evacuated.
Also, an evacuation mark is maintained and advanced every time.
Prior to this CL, the evacuation mark was always incremented,
even if the next bucket to be evacuated had already been evacuated.
This CL changes evacuation mark advancement to skip previously
evacuated buckets. This has the effect of making map evacuation both
more aggressive and more consistent.

Aggressive map evacuation is good. While the map is growing,
map accesses must check two buckets, which may be far apart in memory.
Map growth also delays garbage collection.
And if map evacuation is not aggressive enough, there is a risk that
a populate-once read-many map may be stuck permanently in map growth.
This CL does not eliminate that possibility, but it shrinks the window.

There is minimal impact on map benchmarks:

name old time/op new time/op delta
MapPop100-8 12.4µs ±11% 12.4µs ± 7% ~ (p=0.798 n=15+15)
MapPop1000-8 240µs ± 8% 235µs ± 8% ~ (p=0.217 n=15+14)
MapPop10000-8 4.49ms ±10% 4.51ms ±15% ~ (p=1.000 n=15+13)
MegMap-8 11.9ns ± 2% 11.8ns ± 0% -1.01% (p=0.000 n=15+11)
MegOneMap-8 9.30ns ± 1% 9.29ns ± 1% ~ (p=0.955 n=14+14)
MegEqMap-8 31.9µs ± 5% 31.9µs ± 3% ~ (p=0.935 n=15+15)
MegEmptyMap-8 2.41ns ± 2% 2.41ns ± 0% ~ (p=0.594 n=12+14)
SmallStrMap-8 12.8ns ± 1% 12.7ns ± 1% ~ (p=0.569 n=14+13)
MapStringKeysEight_16-8 13.6ns ± 1% 13.7ns ± 2% ~ (p=0.100 n=13+15)
MapStringKeysEight_32-8 12.1ns ± 1% 12.1ns ± 2% ~ (p=0.340 n=15+15)
MapStringKeysEight_64-8 12.1ns ± 1% 12.1ns ± 2% ~ (p=0.582 n=15+14)
MapStringKeysEight_1M-8 12.0ns ± 1% 12.1ns ± 1% ~ (p=0.267 n=15+14)
IntMap-8 7.96ns ± 1% 7.97ns ± 2% ~ (p=0.991 n=15+13)
RepeatedLookupStrMapKey32-8 15.8ns ± 2% 15.8ns ± 1% ~ (p=0.393 n=15+14)
RepeatedLookupStrMapKey1M-8 35.3µs ± 2% 35.3µs ± 1% ~ (p=0.815 n=15+15)
NewEmptyMap-8 36.0ns ± 4% 36.4ns ± 7% ~ (p=0.270 n=15+15)
NewSmallMap-8 85.5ns ± 1% 85.6ns ± 1% ~ (p=0.674 n=14+15)
MapIter-8 89.9ns ± 6% 90.8ns ± 6% ~ (p=0.467 n=15+15)
MapIterEmpty-8 10.0ns ±22% 10.0ns ±25% ~ (p=0.846 n=15+15)
SameLengthMap-8 4.18ns ± 1% 4.17ns ± 1% ~ (p=0.653 n=15+14)
BigKeyMap-8 20.2ns ± 1% 20.1ns ± 1% -0.82% (p=0.002 n=15+15)
BigValMap-8 22.5ns ± 8% 22.3ns ± 6% ~ (p=0.615 n=15+15)
SmallKeyMap-8 15.3ns ± 1% 15.3ns ± 1% ~ (p=0.754 n=15+14)
ComplexAlgMap-8 58.4ns ± 1% 58.7ns ± 1% +0.52% (p=0.000 n=14+15)

There is a tiny but detectable difference in the compiler:

name old time/op new time/op delta
Template 218ms ± 5% 219ms ± 4% ~ (p=0.094 n=98+98)
Unicode 93.6ms ± 5% 93.6ms ± 4% ~ (p=0.910 n=94+95)
GoTypes 596ms ± 5% 598ms ± 6% ~ (p=0.533 n=98+100)
Compiler 2.72s ± 3% 2.72s ± 4% ~ (p=0.238 n=100+99)
SSA 4.11s ± 3% 4.11s ± 3% ~ (p=0.864 n=99+98)
Flate 129ms ± 6% 129ms ± 4% ~ (p=0.522 n=98+96)
GoParser 151ms ± 4% 151ms ± 4% -0.48% (p=0.017 n=96+96)
Reflect 379ms ± 3% 376ms ± 4% -0.57% (p=0.011 n=99+99)
Tar 112ms ± 5% 112ms ± 6% ~ (p=0.688 n=93+95)
XML 214ms ± 4% 214ms ± 5% ~ (p=0.968 n=100+99)
StdCmd 16.2s ± 2% 16.2s ± 2% -0.26% (p=0.048 n=99+99)

name old user-ns/op new user-ns/op delta
Template 252user-ms ± 4% 250user-ms ± 4% -0.63% (p=0.020 n=98+97)
Unicode 113user-ms ± 7% 114user-ms ± 5% ~ (p=0.057 n=97+94)
GoTypes 776user-ms ± 5% 777user-ms ± 5% ~ (p=0.375 n=97+96)
Compiler 3.61user-s ± 3% 3.60user-s ± 3% ~ (p=0.445 n=98+93)
SSA 5.84user-s ± 6% 5.85user-s ± 5% ~ (p=0.542 n=100+95)
Flate 154user-ms ± 5% 154user-ms ± 5% ~ (p=0.699 n=99+99)
GoParser 184user-ms ± 6% 183user-ms ± 4% ~ (p=0.557 n=98+95)
Reflect 461user-ms ± 5% 462user-ms ± 4% ~ (p=0.853 n=97+99)
Tar 130user-ms ± 5% 129user-ms ± 6% ~ (p=0.567 n=93+100)
XML 257user-ms ± 6% 258user-ms ± 6% ~ (p=0.205 n=99+100)

Change-Id: Id92dd54a152904069aac415e6aaaab5c67f5f476
Reviewed-on: https://go-review.googlesource.com/37011Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

064e44f2

cmd/internal/obj: remove unused Getcallerpc function · 9bc67bb4

Matthew Dempsky authored Feb 28, 2017

Change-Id: I0c7b677657326f318e906e109cbda0cfa78c4973
Reviewed-on: https://go-review.googlesource.com/37537
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Michael Hudson-Doyle <michael.hudson@canonical.com>

9bc67bb4

cmd/compile/ssa: more aggressive constant folding · 379567aa

philhofer authored Feb 20, 2017

Add rewrite rules that canonicalize the location
of constants in expressions, and fold conststants
that appear in operations that can be trivially
reassociated.

After this change, the compiler constant-folds
expressions like "4 + x - 1" and "4 & x & 1"

Benchmarks affected on darwin/amd64:

name old time/op new time/op delta
FmtFprintfInt-8 82.1ns ± 1% 81.7ns ± 1% -0.46% (p=0.023 n=8+9)
FmtFprintfIntInt-8 122ns ± 2% 120ns ± 2% -1.48% (p=0.047 n=10+10)
FmtManyArgs-8 493ns ± 0% 486ns ± 1% -1.37% (p=0.000 n=8+10)
Gzip-8 230ms ± 0% 229ms ± 1% -0.46% (p=0.001 n=10+9)
HTTPClientServer-8 74.5µs ± 1% 73.7µs ± 1% -1.11% (p=0.000 n=10+10)
JSONDecode-8 51.7ms ± 0% 51.9ms ± 1% +0.42% (p=0.017 n=10+9)
RegexpMatchEasy0_32-8 82.6ns ± 1% 81.7ns ± 0% -1.02% (p=0.000 n=9+8)
RegexpMatchMedium_32-8 121ns ± 1% 120ns ± 1% -1.48% (p=0.001 n=10+10)
Revcomp-8 426ms ± 1% 400ms ± 1% -6.16% (p=0.000 n=10+10)
TimeFormat-8 330ns ± 1% 327ns ± 0% -0.82% (p=0.000 n=10+10)

name old speed new speed delta
Gzip-8 84.4MB/s ± 0% 84.8MB/s ± 1% +0.47% (p=0.001 n=10+9)
JSONDecode-8 37.6MB/s ± 0% 37.4MB/s ± 1% -0.42% (p=0.016 n=10+9)
RegexpMatchEasy0_32-8 387MB/s ± 1% 392MB/s ± 0% +1.06% (p=0.000 n=9+8)
RegexpMatchMedium_32-8 8.21MB/s ± 1% 8.34MB/s ± 1% +1.58% (p=0.000 n=10+9)
Revcomp-8 597MB/s ± 1% 636MB/s ± 1% +6.57% (p=0.000 n=10+10)

Change-Id: Ie37ff91605b76a984a8400dfd1e34f50bf61c864
Reviewed-on: https://go-review.googlesource.com/37290Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

379567aa

cmd/compile, runtime: specialize convT2x, don't alloc for zero vals · 504bc3ed

Josh Bleecher Snyder authored Feb 03, 2017

Prior to this CL, all runtime conversions
from a concrete value to an interface went
through one of two runtime calls: convT2E or convT2I.
However, in practice, basic types are very common.
Specializing convT2x for those basic types allows
for a more efficient implementation for those types.
For basic scalars and strings, allocation and copying
can use the same methods as normal code.
For pointer-free types, allocation can occur without
zeroing, and copying can take place without GC calls.
For slices, copying is cheaper and simpler.

This CL adds twelve runtime routines:

convT2E16, convT2I16
convT2E32, convT2I32
convT2E64, convT2I64
convT2Estring, convT2Istring
convT2Eslice, convT2Islice
convT2Enoptr, convT2Inoptr

While compiling make.bash, 93% of all convT2x calls
are now to one of these specialized convT2x call.

Within specialized convT2x routines, it is cheap to check
for a zero value, in a way that it is not in general.
When we detect a zero value there, we return a pointer
to zeroVal, rather than allocating.

name old time/op new time/op delta
ConvT2Ezero/zero/16-8 17.9ns ± 2% 3.0ns ± 3% -83.20% (p=0.000 n=56+56)
ConvT2Ezero/zero/32-8 17.8ns ± 2% 3.0ns ± 3% -83.15% (p=0.000 n=59+60)
ConvT2Ezero/zero/64-8 20.1ns ± 1% 3.0ns ± 2% -84.98% (p=0.000 n=57+57)
ConvT2Ezero/zero/str-8 32.6ns ± 1% 3.0ns ± 4% -90.70% (p=0.000 n=59+60)
ConvT2Ezero/zero/slice-8 36.7ns ± 2% 3.0ns ± 2% -91.78% (p=0.000 n=59+59)
ConvT2Ezero/zero/big-8 91.9ns ± 2% 85.9ns ± 2% -6.52% (p=0.000 n=57+57)
ConvT2Ezero/nonzero/16-8 17.7ns ± 2% 12.7ns ± 3% -28.38% (p=0.000 n=55+60)
ConvT2Ezero/nonzero/32-8 17.8ns ± 1% 12.7ns ± 1% -28.44% (p=0.000 n=54+57)
ConvT2Ezero/nonzero/64-8 20.0ns ± 1% 15.0ns ± 1% -24.90% (p=0.000 n=56+58)
ConvT2Ezero/nonzero/str-8 32.6ns ± 1% 25.7ns ± 1% -21.17% (p=0.000 n=58+55)
ConvT2Ezero/nonzero/slice-8 36.8ns ± 2% 30.4ns ± 1% -17.32% (p=0.000 n=60+52)
ConvT2Ezero/nonzero/big-8 92.1ns ± 2% 85.9ns ± 2% -6.70% (p=0.000 n=57+59)

Benchmarks on a real program (the compiler):

name old time/op new time/op delta
Template 227ms ± 5% 221ms ± 2% -2.48% (p=0.000 n=30+26)
Unicode 102ms ± 5% 100ms ± 3% -1.30% (p=0.009 n=30+26)
GoTypes 656ms ± 5% 659ms ± 4% ~ (p=0.208 n=30+30)
Compiler 2.82s ± 2% 2.82s ± 1% ~ (p=0.614 n=29+27)
Flate 128ms ± 2% 128ms ± 5% ~ (p=0.783 n=27+28)
GoParser 158ms ± 3% 158ms ± 3% ~ (p=0.261 n=28+30)
Reflect 408ms ± 7% 401ms ± 3% ~ (p=0.075 n=30+30)
Tar 123ms ± 6% 121ms ± 8% ~ (p=0.287 n=29+30)
XML 220ms ± 2% 220ms ± 4% ~ (p=0.805 n=29+29)

name old user-ns/op new user-ns/op delta
Template 281user-ms ± 4% 279user-ms ± 3% -0.87% (p=0.044 n=28+28)
Unicode 142user-ms ± 4% 141user-ms ± 3% -1.04% (p=0.015 n=30+27)
GoTypes 884user-ms ± 3% 886user-ms ± 2% ~ (p=0.532 n=30+30)
Compiler 3.94user-s ± 3% 3.92user-s ± 1% ~ (p=0.185 n=30+28)
Flate 165user-ms ± 2% 165user-ms ± 4% ~ (p=0.780 n=27+29)
GoParser 209user-ms ± 2% 208user-ms ± 3% ~ (p=0.453 n=28+30)
Reflect 533user-ms ± 6% 526user-ms ± 3% ~ (p=0.057 n=30+30)
Tar 156user-ms ± 6% 154user-ms ± 6% ~ (p=0.133 n=29+30)
XML 288user-ms ± 4% 288user-ms ± 4% ~ (p=0.633 n=30+30)

name old alloc/op new alloc/op delta
Template 41.0MB ± 0% 40.9MB ± 0% -0.11% (p=0.000 n=29+29)
Unicode 32.6MB ± 0% 32.6MB ± 0% ~ (p=0.572 n=29+30)
GoTypes 122MB ± 0% 122MB ± 0% -0.10% (p=0.000 n=30+30)
Compiler 482MB ± 0% 481MB ± 0% -0.07% (p=0.000 n=30+29)
Flate 26.6MB ± 0% 26.6MB ± 0% ~ (p=0.096 n=30+30)
GoParser 32.7MB ± 0% 32.6MB ± 0% -0.06% (p=0.011 n=28+28)
Reflect 84.2MB ± 0% 84.1MB ± 0% -0.17% (p=0.000 n=29+30)
Tar 27.7MB ± 0% 27.7MB ± 0% -0.05% (p=0.032 n=27+28)
XML 44.7MB ± 0% 44.7MB ± 0% ~ (p=0.131 n=28+30)

name old allocs/op new allocs/op delta
Template 373k ± 1% 370k ± 1% -0.76% (p=0.000 n=30+30)
Unicode 325k ± 1% 325k ± 1% ~ (p=0.383 n=29+30)
GoTypes 1.16M ± 0% 1.15M ± 0% -0.75% (p=0.000 n=29+30)
Compiler 4.15M ± 0% 4.13M ± 0% -0.59% (p=0.000 n=30+29)
Flate 238k ± 1% 237k ± 1% -0.62% (p=0.000 n=30+30)
GoParser 304k ± 1% 302k ± 1% -0.64% (p=0.000 n=30+28)
Reflect 1.00M ± 0% 0.99M ± 0% -1.10% (p=0.000 n=29+30)
Tar 245k ± 1% 244k ± 1% -0.59% (p=0.000 n=27+29)
XML 391k ± 1% 389k ± 1% -0.59% (p=0.000 n=29+30)

Change-Id: Id7f456d690567c2b0a96b0d6d64de8784b6e305f
Reviewed-on: https://go-review.googlesource.com/36476
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>

504bc3ed

cmd/compile: update signature of runtime.memclr* · f6fc0dd6

Cherry Zhang authored Feb 19, 2017

runtime.memclr* functions have signatures

func memclrNoHeapPointers(ptr unsafe.Pointer, n uintptr)
func memclrHasPointers(ptr unsafe.Pointer, n uintptr)

Update compiler's copy. Also teach gc/mkbuiltin.go to handle
unsafe.Pointer. The import statement and its support is not
really necessary, but just to make it look like real Go code.

Fixes #19185.

Change-Id: I251d02571fde2716d4727e31e04d56ec04b6f22a
Reviewed-on: https://go-review.googlesource.com/37257
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>

f6fc0dd6

cmd/vet/all: temporarily ignore vendored pprof · d3d2a67c

Josh Bleecher Snyder authored Feb 28, 2017

Change-Id: I3d96b9803dbbd7184f96240bd7944af919ca1376
Reviewed-on: https://go-review.googlesource.com/37579
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

d3d2a67c

cmd/vet: allow shifts by amounts calculated using unsafe · d99d5f7c

Josh Bleecher Snyder authored Feb 28, 2017

The real world code that inspired this fix,
from runtime/pprof/map.go:

	// Compute hash of (stk, tag).
	h := uintptr(0)
	for _, x := range stk {
		h = h<<8 | (h >> (8 * (unsafe.Sizeof(h) - 1)))
		h += uintptr(x) * 41
	}
	h = h<<8 | (h >> (8 * (unsafe.Sizeof(h) - 1)))
	h += uintptr(tag) * 41

Change-Id: I99a95b97cba73811faedb0b9a1b9b54e9a1784a3
Reviewed-on: https://go-review.googlesource.com/37574
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

d99d5f7c

cmd/vet/all: move suspicious shift whitelists to 64 bit · 016569f2

Josh Bleecher Snyder authored Feb 28, 2017

This is an inconsequential consequence of updating
math/big to use math/bits.

Better would be to teach the vet shift test
to size int/uint/uintptr to the platform in use,
eliminating the whole category of "might be too small".
Filed #19321 for that.

Change-Id: I7e0b837bd329132d7a564468c18502dd2e724fc6
Reviewed-on: https://go-review.googlesource.com/37576
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

016569f2

cmd/dist: make the vetall builder have test shards per os/arch · 31f9769c

Brad Fitzpatrick authored Feb 28, 2017

This makes the vetall builder friendly to auto-sharding by the build
coordinator.

Change-Id: I0893f5051ec90e7a6adcb89904ba08cd2d590549
Reviewed-on: https://go-review.googlesource.com/37572Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>

31f9769c

cmd/vet/all: exit with non-zero error code on failure · 8defd9f7

Josh Bleecher Snyder authored Feb 28, 2017

Change-Id: I68e60b155c583fa47aa5ca13d591851009a4e571
Reviewed-on: https://go-review.googlesource.com/37571Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

8defd9f7

cmd/compile: emit fused multiply-{add,subtract} instructions on s390x · bd8a39b6

Michael Munday authored Feb 12, 2017

Explcitly block fused multiply-add pattern matching when a cast is used
after the multiplication, for example:

    - (a * b) + c        // can emit fused multiply-add
    - float64(a * b) + c // cannot emit fused multiply-add

float{32,64} and complex{64,128} casts of matching types are now kept
as OCONV operations rather than being replaced with OCONVNOP operations
because they now imply a rounding operation (and therefore aren't a
no-op anymore).

Operations (for example, multiplication) on complex types may utilize
fused multiply-add and -subtract instructions internally. There is no
way to disable this behavior at the moment.

Improves the performance of the floating point implementation of
poly1305:

name         old speed     new speed     delta
64           246MB/s ± 0%  275MB/s ± 0%  +11.48%   (p=0.000 n=10+8)
1K           312MB/s ± 0%  357MB/s ± 0%  +14.41%  (p=0.000 n=10+10)
64Unaligned  246MB/s ± 0%  274MB/s ± 0%  +11.43%  (p=0.000 n=10+10)
1KUnaligned  312MB/s ± 0%  357MB/s ± 0%  +14.39%   (p=0.000 n=10+8)

Updates #17895.

Change-Id: Ia771d275bb9150d1a598f8cc773444663de5ce16
Reviewed-on: https://go-review.googlesource.com/36963
Run-TryBot: Michael Munday <munday@ca.ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>

bd8a39b6

crypto/sha512: fix checkAVX2 · a38a2d02

David du Colombier authored Feb 28, 2017

The checkAVX2 test doesn't appear to be correct,
because it always returns the value of support_bmi2,
even if the value of support_avx2 is false.

Consequently, checkAVX2 always returns true, as long
as BMI2 is supported, even if AVX2 is not supported.

We change checkAVX2 to return false when support_avx2
is false.

Fixes #19316.

Change-Id: I2ec9dfaa09f4b54c4a03d60efef891b955d60578
Reviewed-on: https://go-review.googlesource.com/37590
Run-TryBot: David du Colombier <0intro@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>

a38a2d02

cmd/compile: fix assignment order in string range loop · a8f07310

Martin Möhrmann authored Dec 19, 2016

Fixes #18376.

Change-Id: I4fe24f479311cd4cd1bdad9a966b681e50e3d500
Reviewed-on: https://go-review.googlesource.com/35955Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: Martin Möhrmann <moehrmann@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

a8f07310

bytes: make bytes.Buffer cache-friendly · 55310403

Carlo Alberto Ferraris authored Feb 25, 2017

During benchmark of an internal tool we found out that (*Buffer).Reset() was
surprisingly showing up in CPU profiles.

This CL contains two related changes aimed at speeding up Reset():
1. Create a fast path for Truncate(0) by moving the logic to Reset()
(this makes Reset() a simple leaf func that gets inlined since it
gets compiled to 3 MOVx instructions). Accordingly change calls in
the rest of the Buffer methods to call Reset() instead of Truncate(0).
2. Reorder the fields in the Buffer struct so that frequently accessed
fields are packed together (buf, off, lastRead). This also make them
likely to be in the same cacheline.

Ideally it would be advisable to have Buffer{} cacheline-aligned, but I
couldn't find a way to do this without changing the size of the bootstrap
array (but this will cause some regressions, because it will make duffcopy
show up in CPU profiles where it wasn't showing up before).

go1 benchmarks are not really affected, but some other benchmarks that
exercise Buffer more show improvements:

name old time/op new time/op delta
BinaryTree17-4 2.46s ± 9% 2.43s ± 3% ~ (p=0.982 n=14+14)
Fannkuch11-4 2.98s ± 1% 2.90s ± 1% -2.58% (p=0.000 n=15+14)
FmtFprintfEmpty-4 45.2ns ± 1% 45.2ns ± 1% ~ (p=0.494 n=14+15)
FmtFprintfString-4 76.8ns ± 1% 83.1ns ± 2% +8.23% (p=0.000 n=10+15)
FmtFprintfInt-4 78.0ns ± 2% 74.6ns ± 1% -4.46% (p=0.000 n=15+15)
FmtFprintfIntInt-4 113ns ± 1% 109ns ± 2% -2.91% (p=0.000 n=13+15)
FmtFprintfPrefixedInt-4 152ns ± 2% 143ns ± 2% -6.04% (p=0.000 n=15+14)
FmtFprintfFloat-4 224ns ± 1% 222ns ± 2% -1.08% (p=0.001 n=15+14)
FmtManyArgs-4 464ns ± 2% 463ns ± 2% ~ (p=0.303 n=14+15)
GobDecode-4 6.25ms ± 2% 6.32ms ± 3% +1.20% (p=0.002 n=14+14)
GobEncode-4 5.41ms ± 2% 5.41ms ± 2% ~ (p=0.967 n=15+15)
Gzip-4 215ms ± 2% 218ms ± 2% +1.35% (p=0.002 n=15+15)
Gunzip-4 34.3ms ± 2% 34.2ms ± 2% ~ (p=0.539 n=15+15)
HTTPClientServer-4 76.4µs ± 2% 75.4µs ± 1% -1.31% (p=0.000 n=15+15)
JSONEncode-4 14.7ms ± 2% 14.6ms ± 3% ~ (p=0.094 n=14+14)
JSONDecode-4 48.0ms ± 1% 48.5ms ± 1% +0.92% (p=0.001 n=14+12)
Mandelbrot200-4 4.04ms ± 2% 4.06ms ± 1% ~ (p=0.108 n=15+13)
GoParse-4 2.99ms ± 2% 3.00ms ± 1% ~ (p=0.130 n=15+13)
RegexpMatchEasy0_32-4 78.3ns ± 1% 79.5ns ± 1% +1.51% (p=0.000 n=15+14)
RegexpMatchEasy0_1K-4 185ns ± 1% 186ns ± 1% +0.76% (p=0.005 n=15+15)
RegexpMatchEasy1_32-4 79.0ns ± 2% 76.7ns ± 1% -2.87% (p=0.000 n=14+15)

name old speed new speed delta
GobDecode-4 123MB/s ± 2% 121MB/s ± 3% -1.18% (p=0.002 n=14+14)
GobEncode-4 142MB/s ± 2% 142MB/s ± 1% ~ (p=0.959 n=15+15)
Gzip-4 90.3MB/s ± 2% 89.1MB/s ± 2% -1.34% (p=0.002 n=15+15)
Gunzip-4 565MB/s ± 2% 567MB/s ± 2% ~ (p=0.539 n=15+15)
JSONEncode-4 132MB/s ± 2% 133MB/s ± 3% ~ (p=0.091 n=14+14)
JSONDecode-4 40.4MB/s ± 1% 40.0MB/s ± 1% -0.92% (p=0.001 n=14+12)
GoParse-4 19.4MB/s ± 2% 19.3MB/s ± 1% ~ (p=0.121 n=15+13)
RegexpMatchEasy0_32-4 409MB/s ± 1% 403MB/s ± 1% -1.47% (p=0.000 n=15+14)
RegexpMatchEasy0_1K-4 5.53GB/s ± 1% 5.49GB/s ± 1% -0.86% (p=0.002 n=15+15)
RegexpMatchEasy1_32-4 405MB/s ± 2% 417MB/s ± 1% +2.94% (p=0.000 n=14+15)

name old time/op new time/op delta
PoolsSingle1K-4 34.9ns ± 2% 30.4ns ± 4% -12.80% (p=0.000 n=15+15)
PoolsSingle64K-4 36.9ns ± 1% 34.4ns ± 4% -6.72% (p=0.000 n=14+15)
PoolsRandomSmall-4 34.8ns ± 3% 29.5ns ± 1% -15.19% (p=0.000 n=15+14)
PoolsRandomLarge-4 38.6ns ± 1% 34.3ns ± 3% -11.17% (p=0.000 n=14+15)
PoolSingle1K-4 26.1ns ± 1% 21.2ns ± 2% -18.59% (p=0.000 n=15+14)
PoolSingle64K-4 26.7ns ± 2% 21.5ns ± 2% -19.72% (p=0.000 n=15+15)
MakeSingle1K-4 24.2ns ± 2% 24.3ns ± 3% ~ (p=0.132 n=13+15)
MakeSingle64K-4 6.76µs ± 1% 6.96µs ± 5% +2.94% (p=0.002 n=13+13)
MakeRandomSmall-4 531ns ± 4% 538ns ± 5% ~ (p=0.066 n=14+15)
MakeRandomLarge-4 152µs ± 0% 152µs ± 1% -0.31% (p=0.001 n=14+13)

Change-Id: I86d7d9d2cac65335baf62214fbb35ba0fd8f9528
Reviewed-on: https://go-review.googlesource.com/37416
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

55310403

cmd/compile: fold (NegNN (ConstNN ...)) · 417f49a3

Josh Bleecher Snyder authored Feb 18, 2017

Fix up and enable a few rules.
They trigger a handful of times in std,
despite the frontend handling.

Change-Id: I83378c057cbbc95a4f2b58cd8c36aec0e9dc547f
Reviewed-on: https://go-review.googlesource.com/37227
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>

417f49a3

cmd/compile: fix merging of s390x conditional moves into branch conditions · 4dbcb53d

Michael Munday authored Feb 21, 2017

A type conversion inserted between MOVD{LT,LE,GT,GE,EQ,NE} and CMPWconst
by CL 36256 broke the rewrite rule designed to merge the two.
This results in simple for loops (e.g. for i := 0; i < N; i++ {})
emitting two comparisons instead of one, plus a conditional move.

This CL explicitly types the input to CMPWconst so that the type conversion
can be omitted. It also adds a test to check that conditional moves aren't
emitted for loops with 'less than' conditions (i.e. i < N) on s390x.

Fixes #19227.

Change-Id: Ia39e806ed723791c3c755951aef23f957828ea3e
Reviewed-on: https://go-review.googlesource.com/37334Reviewed-by: Keith Randall <khr@golang.org>

4dbcb53d

net/url: document the package better · 1b31c9ff

Joe Tsai authored Feb 02, 2017

Changes made:
* Adjust the documented form for a URL to make it more obvious what
happens when the scheme is missing.
* Remove references to Go1.5. We are sufficiently far along enough
that this distinction no longer matters.
* Remove the "Opaque" example which provides a hacky and misleading
use of the Opaque field. This workaround is no longer necessary
since RawPath was added in Go1.5 and the obvious approach just works:
	// The raw string "/%2f/" will be sent as expected.
	req, _ := http.NewRequest("GET", "https://example.com/%2f/")

Fixes #18824

Change-Id: Ie33d27222e06025ce8025f8a0f04b601aaee1513
Reviewed-on: https://go-review.googlesource.com/36127
Run-TryBot: Joe Tsai <thebrokentoaster@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

1b31c9ff

27 Feb, 2017 15 commits

go/importer: support importing directly from source · f81466ce

Robert Griesemer authored Feb 23, 2017

For #11415.

Change-Id: I5da39dad059113cfc4276152390aa4925bd18862
Reviewed-on: https://go-review.googlesource.com/37405
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Alan Donovan <adonovan@google.com>

f81466ce

cmd/internal/obj, runtime: update funcdata comments · bab19104

Austin Clements authored Feb 20, 2017

The comments in cmd/internal/obj/funcdata.go are identical to the
comments in runtime/funcdata.h, but the majority of the definitions
they refer to don't apply to Go sources and have been stripped out of
funcdata.go.

Remove these stale comments from funcdata.go and clean up the
references to other copies of the PCDATA and FUNCDATA indexes.

Change-Id: I5d6e49a6e586cc9aecd7c3ce1567679f2a605884
Reviewed-on: https://go-review.googlesource.com/37330Reviewed-by: Keith Randall <khr@golang.org>

bab19104

os/user: add Go implementation of LookupGroup, LookupGroupId · 949f95e7

Kevin Burke authored Nov 30, 2016

If cgo is not available, parse /etc/group in Go to find the name/gid
we need. This does not consult the Network Information System (NIS),
/etc/nsswitch.conf or any other libc extensions to /etc/group.

Fixes #18102.

Change-Id: I6ae4fe0e2c899396c45cdf243d5483113932657c
Reviewed-on: https://go-review.googlesource.com/33713Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

949f95e7

go/internal/srcimporter: implemented srcimporter · 459d061c

Robert Griesemer authored Feb 22, 2017

For #11415.

Change-Id: I87a8f534ab9dfd5022422457ea637b342c057d77
Reviewed-on: https://go-review.googlesource.com/37393Reviewed-by: Alan Donovan <adonovan@google.com>

459d061c

cmd/compile: ignore some dead code during escape analysis · 1e29cd8c

Josh Bleecher Snyder authored Feb 27, 2017

This is the escape analysis analog of CL 37499.

Fixes #12397
Fixes #16871

The only "moved to heap" decisions eliminated by this
CL in std+cmd are:

cmd/compile/internal/gc/const.go:1514: moved to heap: ac
cmd/compile/internal/gc/const.go:1515: moved to heap: bd
cmd/compile/internal/gc/const.go:1516: moved to heap: bc
cmd/compile/internal/gc/const.go:1517: moved to heap: ad
cmd/compile/internal/gc/const.go:1546: moved to heap: ac
cmd/compile/internal/gc/const.go:1547: moved to heap: bd
cmd/compile/internal/gc/const.go:1548: moved to heap: bc
cmd/compile/internal/gc/const.go:1549: moved to heap: ad
cmd/compile/internal/gc/const.go:1550: moved to heap: cc_plus
cmd/compile/internal/gc/export.go:162: moved to heap: copy
cmd/compile/internal/gc/mpfloat.go:66: moved to heap: b
cmd/compile/internal/gc/mpfloat.go:97: moved to heap: b

Change-Id: I0d420b69c84a41ba9968c394e8957910bab5edea
Reviewed-on: https://go-review.googlesource.com/37508Reviewed-by: David Chase <drchase@google.com>

1e29cd8c

cmd/compile/internal/gc: refactor liveness bitmap generation · 7b8f5118

Matthew Dempsky authored Feb 24, 2017

Keep liveness bit vectors as simple live-variable vectors during
liveness analysis. We can defer expanding them into runtime heap
bitmaps until we're actually writing out the symbol data, and then we
only need temporary memory to expand one bitmap at a time.

This is logically cleaner (e.g., we no longer depend on stack frame
layout during analysis) and saves a little bit on allocations.

name old alloc/op new alloc/op delta
Template 41.4MB ± 0% 41.3MB ± 0% -0.28% (p=0.000 n=60+60)
Unicode 32.6MB ± 0% 32.6MB ± 0% -0.11% (p=0.000 n=59+60)
GoTypes 119MB ± 0% 119MB ± 0% -0.35% (p=0.000 n=60+59)
Compiler 483MB ± 0% 481MB ± 0% -0.47% (p=0.000 n=59+60)

name old allocs/op new allocs/op delta
Template 381k ± 1% 380k ± 1% -0.32% (p=0.000 n=60+60)
Unicode 325k ± 1% 325k ± 1% ~ (p=0.867 n=60+60)
GoTypes 1.16M ± 0% 1.15M ± 0% -0.40% (p=0.000 n=60+59)
Compiler 4.22M ± 0% 4.19M ± 0% -0.61% (p=0.000 n=59+60)

Passes toolstash -cmp.

Change-Id: I8175efe55201ffb5017f79ae6cb90df03f1b7e99
Reviewed-on: https://go-review.googlesource.com/37458
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>

7b8f5118

cmd/internal/obj/x86: improve static branch prediction for wrapper prologue · 88f423ed

Josh Bleecher Snyder authored Feb 10, 2017

Static branch prediction assumes that forward branches are not taken.
The existing wrapper prologue almost always takes the first forward
branch.
Move the rare case to the end of the function.

This CL is amd64 only. Other architectures will be done in separate CLs.

Updates #19042.

Package sort benchmarks:

SearchWrappers-8       104ns ± 2%   104ns ± 0%  -0.41%  (p=0.006 n=30+41)
SortString1K-8         128µs ± 1%   128µs ± 1%  -0.25%  (p=0.045 n=30+56)
SortString1K_Slice-8   117µs ± 1%   117µs ± 1%    ~     (p=0.855 n=30+59)
StableString1K-8      18.6µs ± 1%  18.6µs ± 1%    ~     (p=0.599 n=29+60)
SortInt1K-8           61.0µs ± 1%  56.5µs ± 1%  -7.36%  (p=0.000 n=29+58)
StableInt1K-8         74.6µs ± 1%  70.4µs ± 3%  -5.54%  (p=0.000 n=28+60)
StableInt1K_Slice-8   59.9µs ± 1%  58.3µs ± 4%  -2.64%  (p=0.000 n=29+60)
SortInt64K-8          6.02ms ± 2%  5.98ms ± 2%  -0.60%  (p=0.000 n=29+59)
SortInt64K_Slice-8    5.07ms ± 2%  5.05ms ± 2%  -0.38%  (p=0.006 n=30+58)
StableInt64K-8        6.41ms ± 1%  6.22ms ± 1%  -3.00%  (p=0.000 n=27+58)
Sort1e2-8             37.4µs ± 1%  37.1µs ± 1%  -0.91%  (p=0.000 n=30+57)
Stable1e2-8           74.8µs ± 1%  75.2µs ± 1%  +0.52%  (p=0.000 n=30+57)
Sort1e4-8             8.11ms ± 1%  8.01ms ± 1%  -1.20%  (p=0.000 n=30+59)
Stable1e4-8           24.3ms ± 1%  24.3ms ± 1%    ~     (p=0.157 n=30+60)
Sort1e6-8              1.25s ± 1%   1.23s ± 1%  -1.43%  (p=0.000 n=29+58)
Stable1e6-8            4.93s ± 1%   4.90s ± 1%  -0.56%  (p=0.000 n=29+59)
[Geo mean]             720µs        709µs       -1.52%

Assembly for sort.(*intPairs).Swap:

Before:

"".(*intPairs).Swap t=1 size=147 args=0x18 locals=0x8
	0x0000 00000 (<autogenerated>:1)	TEXT	"".(*intPairs).Swap(SB), $8-24
	0x0000 00000 (<autogenerated>:1)	MOVQ	(TLS), CX
	0x0009 00009 (<autogenerated>:1)	SUBQ	$8, SP
	0x000d 00013 (<autogenerated>:1)	MOVQ	BP, (SP)
	0x0011 00017 (<autogenerated>:1)	LEAQ	(SP), BP
	0x0015 00021 (<autogenerated>:1)	MOVQ	32(CX), BX
	0x0019 00025 (<autogenerated>:1)	TESTQ	BX, BX
	0x001c 00028 (<autogenerated>:1)	JEQ	43
	0x001e 00030 (<autogenerated>:1)	LEAQ	16(SP), DI
	0x0023 00035 (<autogenerated>:1)	CMPQ	(BX), DI
	0x0026 00038 (<autogenerated>:1)	JNE	43
	0x0028 00040 (<autogenerated>:1)	MOVQ	SP, (BX)
	0x002b 00043 (<autogenerated>:1)	NOP
	0x002b 00043 (<autogenerated>:1)	FUNCDATA	$0, gclocals·e6397a44f8e1b6e77d0f200b4fba5269(SB)
	0x002b 00043 (<autogenerated>:1)	FUNCDATA	$1, gclocals·69c1753bd5f81501d95132d08af04464(SB)
	0x002b 00043 (<autogenerated>:1)	MOVQ	""..this+16(FP), AX
	0x0030 00048 (<autogenerated>:1)	TESTQ	AX, AX
	0x0033 00051 (<autogenerated>:1)	JEQ	$0, 140
	0x0035 00053 (<autogenerated>:1)	MOVQ	(AX), CX
	0x0038 00056 (<autogenerated>:1)	MOVQ	8(AX), AX
	0x003c 00060 (<autogenerated>:1)	MOVQ	"".i+24(FP), DX
	0x0041 00065 (<autogenerated>:1)	CMPQ	DX, AX
	0x0044 00068 (<autogenerated>:1)	JCC	$0, 133
	0x0046 00070 (<autogenerated>:1)	SHLQ	$4, DX
	0x004a 00074 (<autogenerated>:1)	MOVQ	8(CX)(DX*1), BX
	0x004f 00079 (<autogenerated>:1)	MOVQ	(CX)(DX*1), SI
	0x0053 00083 (<autogenerated>:1)	MOVQ	"".j+32(FP), DI
	0x0058 00088 (<autogenerated>:1)	CMPQ	DI, AX
	0x005b 00091 (<autogenerated>:1)	JCC	$0, 133
	0x005d 00093 (<autogenerated>:1)	SHLQ	$4, DI
	0x0061 00097 (<autogenerated>:1)	MOVQ	8(CX)(DI*1), AX
	0x0066 00102 (<autogenerated>:1)	MOVQ	(CX)(DI*1), R8
	0x006a 00106 (<autogenerated>:1)	MOVQ	R8, (CX)(DX*1)
	0x006e 00110 (<autogenerated>:1)	MOVQ	AX, 8(CX)(DX*1)
	0x0073 00115 (<autogenerated>:1)	MOVQ	SI, (CX)(DI*1)
	0x0077 00119 (<autogenerated>:1)	MOVQ	BX, 8(CX)(DI*1)
	0x007c 00124 (<autogenerated>:1)	MOVQ	(SP), BP
	0x0080 00128 (<autogenerated>:1)	ADDQ	$8, SP
	0x0084 00132 (<autogenerated>:1)	RET
	0x0085 00133 (<autogenerated>:1)	PCDATA	$0, $1
	0x0085 00133 (<autogenerated>:1)	CALL	runtime.panicindex(SB)
	0x008a 00138 (<autogenerated>:1)	UNDEF
	0x008c 00140 (<autogenerated>:1)	PCDATA	$0, $1
	0x008c 00140 (<autogenerated>:1)	CALL	runtime.panicwrap(SB)
	0x0091 00145 (<autogenerated>:1)	UNDEF

After:

"".(*intPairs).Swap t=1 size=149 args=0x18 locals=0x8
	0x0000 00000 (<autogenerated>:1)	TEXT	"".(*intPairs).Swap(SB), $8-24
	0x0000 00000 (<autogenerated>:1)	MOVQ	(TLS), CX
	0x0009 00009 (<autogenerated>:1)	SUBQ	$8, SP
	0x000d 00013 (<autogenerated>:1)	MOVQ	BP, (SP)
	0x0011 00017 (<autogenerated>:1)	LEAQ	(SP), BP
	0x0015 00021 (<autogenerated>:1)	MOVQ	32(CX), BX
	0x0019 00025 (<autogenerated>:1)	TESTQ	BX, BX
	0x001c 00028 (<autogenerated>:1)	JNE	134
	0x001e 00030 (<autogenerated>:1)	NOP
	0x001e 00030 (<autogenerated>:1)	FUNCDATA	$0, gclocals·e6397a44f8e1b6e77d0f200b4fba5269(SB)
	0x001e 00030 (<autogenerated>:1)	FUNCDATA	$1, gclocals·69c1753bd5f81501d95132d08af04464(SB)
	0x001e 00030 (<autogenerated>:1)	MOVQ	""..this+16(FP), AX
	0x0023 00035 (<autogenerated>:1)	TESTQ	AX, AX
	0x0026 00038 (<autogenerated>:1)	JEQ	$0, 127
	0x0028 00040 (<autogenerated>:1)	MOVQ	(AX), CX
	0x002b 00043 (<autogenerated>:1)	MOVQ	8(AX), AX
	0x002f 00047 (<autogenerated>:1)	MOVQ	"".i+24(FP), DX
	0x0034 00052 (<autogenerated>:1)	CMPQ	DX, AX
	0x0037 00055 (<autogenerated>:1)	JCC	$0, 120
	0x0039 00057 (<autogenerated>:1)	SHLQ	$4, DX
	0x003d 00061 (<autogenerated>:1)	MOVQ	8(CX)(DX*1), BX
	0x0042 00066 (<autogenerated>:1)	MOVQ	(CX)(DX*1), SI
	0x0046 00070 (<autogenerated>:1)	MOVQ	"".j+32(FP), DI
	0x004b 00075 (<autogenerated>:1)	CMPQ	DI, AX
	0x004e 00078 (<autogenerated>:1)	JCC	$0, 120
	0x0050 00080 (<autogenerated>:1)	SHLQ	$4, DI
	0x0054 00084 (<autogenerated>:1)	MOVQ	8(CX)(DI*1), AX
	0x0059 00089 (<autogenerated>:1)	MOVQ	(CX)(DI*1), R8
	0x005d 00093 (<autogenerated>:1)	MOVQ	R8, (CX)(DX*1)
	0x0061 00097 (<autogenerated>:1)	MOVQ	AX, 8(CX)(DX*1)
	0x0066 00102 (<autogenerated>:1)	MOVQ	SI, (CX)(DI*1)
	0x006a 00106 (<autogenerated>:1)	MOVQ	BX, 8(CX)(DI*1)
	0x006f 00111 (<autogenerated>:1)	MOVQ	(SP), BP
	0x0073 00115 (<autogenerated>:1)	ADDQ	$8, SP
	0x0077 00119 (<autogenerated>:1)	RET
	0x0078 00120 (<autogenerated>:1)	PCDATA	$0, $1
	0x0078 00120 (<autogenerated>:1)	CALL	runtime.panicindex(SB)
	0x007d 00125 (<autogenerated>:1)	UNDEF
	0x007f 00127 (<autogenerated>:1)	PCDATA	$0, $1
	0x007f 00127 (<autogenerated>:1)	CALL	runtime.panicwrap(SB)
	0x0084 00132 (<autogenerated>:1)	UNDEF
	0x0086 00134 (<autogenerated>:1)	LEAQ	16(SP), DI
	0x008b 00139 (<autogenerated>:1)	CMPQ	(BX), DI
	0x008e 00142 (<autogenerated>:1)	JNE	30
	0x0090 00144 (<autogenerated>:1)	MOVQ	SP, (BX)
	0x0093 00147 (<autogenerated>:1)	JMP	30

Change-Id: Ie8c37f384bba10fbacaa754bb0a6b0a7e520ef01
Reviewed-on: https://go-review.googlesource.com/36893Reviewed-by: Keith Randall <khr@golang.org>

88f423ed

cmd/compile/internal/gc: simplify ascompatte · f7f3514b

Matthew Dempsky authored Feb 22, 2017

Passes toolstash -cmp.

Change-Id: Ibb51ccaf29ee97c3463543175c9ac7b85ea10a7f
Reviewed-on: https://go-review.googlesource.com/37339Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>

f7f3514b

runtime: remove unused RaceSemacquire declaration · ba6e5776

Dmitry Vyukov authored Feb 27, 2017

These functions are not defined and are not used.

Fixes #19290

Change-Id: I2978147220af83cf319f7439f076c131870fb9ee
Reviewed-on: https://go-review.googlesource.com/37448Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Dmitry Vyukov <dvyukov@google.com>
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ba6e5776

go/build: move math/bits into L1 set of dependencies · 31e63346

Robert Griesemer authored Feb 27, 2017

Per suggestion from rsc.

Change-Id: I4b61ec6f35ffaaa792b75e011fbba1bdfbabc1f6
Reviewed-on: https://go-review.googlesource.com/37501
Run-TryBot: Robert Griesemer <gri@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

31e63346

net/http: update bundles http2 · 5ae7cbff

Tom Bergan authored Feb 27, 2017

Updates http2 to x/net/http2 git rev 906cda9 for:

http2: add configurable knobs for the server's receive window
https://golang.org/cl/37226

http2/hpack: speedup Encoder.searchTable
https://golang.org/cl/37406

http2: Add opt-in option to Framer to allow DataFrame struct reuse
https://golang.org/cl/34812

http2: replace fixedBuffer with dataBuffer
https://golang.org/cl/37400

http2/hpack: remove hpack's constant time string comparison
https://golang.org/cl/37394

Updates golang/go#16512
Updates golang/go#18404

Change-Id: I1ad7c95c404ead4ced7f85af061cf811b299a288
Reviewed-on: https://go-review.googlesource.com/37500Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
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5ae7cbff

cmd/compile: simplify and clean up inlnode · 0df81e88

Josh Bleecher Snyder authored Feb 27, 2017

Change-Id: I0d14d68b57e8605cdae8a45d6fa97255a42297d8
Reviewed-on: https://go-review.googlesource.com/37521
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

0df81e88

cmd/compile: ignore some dead code when deciding whether to inline · 566e72d0

Josh Bleecher Snyder authored Feb 26, 2017

Constant evaluation provides some rudimentary
knowledge of dead code at inlining decision time.
Use it.

This CL addresses only dead code inside if statements.
For statements are never inlined anyway,
and dead code inside for statements is rare.
Analyzing switch statements is worth doing,
but it is more complicated, since we would have
to evaluate each case; leave it for later.

Fixes #9274

After this CL, the following functions in std+cmd
can be newly inlined:

cmd/internal/obj/x86/asm6.go:3122: can inline subreg
cmd/vendor/golang.org/x/arch/x86/x86asm/decode.go:172: can inline instPrefix
cmd/vendor/golang.org/x/arch/x86/x86asm/decode.go:202: can inline truncated
go/constant/value.go:234: can inline makeFloat
go/types/labels.go:52: can inline (*block).insert
math/big/float.go:231: can inline (*Float).Sign
math/bits/bits.go:57: can inline OnesCount
net/http/server.go:597: can inline (*Server).newConn
runtime/hashmap.go:1165: can inline reflect_maplen
runtime/proc.go:207: can inline os_beforeExit
runtime/signal_unix.go:55: can inline init.5
runtime/stack.go:1081: can inline gostartcallfn

Change-Id: I4c92fb96aa0c3d33df7b3f2da548612e79b56b5b
Reviewed-on: https://go-review.googlesource.com/37499Reviewed-by: Matthew Dempsky <mdempsky@google.com>

566e72d0

runtime/pprof: handle empty stack traces in Profile.Add · c7894924

Josh Bleecher Snyder authored Feb 11, 2017

If the caller passes a large number to Profile.Add,
the list of pcs is empty, which results in junk
(a nil pc) being recorded. Check for that explicitly,
and replace such stack traces with a lostProfileEvent.

Fixes #18836.

Change-Id: I99c96aa67dd5525cd239ea96452e6e8fcb25ce02
Reviewed-on: https://go-review.googlesource.com/36891Reviewed-by: Russ Cox <rsc@golang.org>

c7894924

os/user: rename group cgo file · eae657e9

Kevin Burke authored Feb 27, 2017

In another CL, I'll add a pure Go implementation of lookupGroup and
lookupGroupId in lookup_unix.go, but attempting that in one CL makes
the diff too difficult to read.

Updates #18102.

Change-Id: If8e26cee5efd30385763430f34304c70165aef32
Reviewed-on: https://go-review.googlesource.com/37497Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
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eae657e9

26 Feb, 2017 1 commit

os: skip atime-going-backwards test on NetBSD for now · 4b224852

Brad Fitzpatrick authored Feb 26, 2017

That failing test is preventing other tests from running.
Let's see what else is broken.

Updates #19293

Change-Id: I4c5784be94103ef882f29dec9db08d76a48aff28
Reviewed-on: https://go-review.googlesource.com/37492
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matt Layher <mdlayher@gmail.com>

4b224852

25 Feb, 2017 1 commit

math/bits: faster Reverse8/16 functions using table lookups · e18adbf8

Robert Griesemer authored Feb 24, 2017

Measured on 2.3 GHz Intel Core i7, running macOS 10.12.3:

benchmark                old ns/op     new ns/op     delta
BenchmarkReverse8-8      1.70          0.99          -41.76%
BenchmarkReverse16-8     2.24          1.32          -41.07%

Fixes #19279.

Change-Id: I398cf8a3513b7fa63c130efc7846a7c5353999d4
Reviewed-on: https://go-review.googlesource.com/37459
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

e18adbf8