1. 26 Apr, 2018 2 commits
    • Russ Cox's avatar
      cmd/go: disambiguate for-test packages in failure output · 1a64025f
      Russ Cox authored
      Now that we can tell when a package is a split-off copy
      for testing, show that in the build failures.
      For example, instead of:
      
      	# regexp/syntax
      	../../regexp/syntax/parse.go:9:2: can't find import: "strings"
      	# path/filepath
      	../../path/filepath/match.go:12:2: can't find import: "strings"
      	# flag
      	../../flag/flag.go:75:2: can't find import: "strings"
      
      we now print
      
      	# regexp/syntax [strings.test]
      	../../regexp/syntax/parse.go:9:2: can't find import: "strings"
      	# path/filepath [strings.test]
      	../../path/filepath/match.go:12:2: can't find import: "strings"
      	# flag [strings.test]
      	../../flag/flag.go:75:2: can't find import: "strings"
      
      which gives more of a hint about what is wrong.
      
      This is especially helpful if a package is being built multiple times,
      since it explains why an error might appear multiple times:
      
      	$ go test regexp encoding/json
      	# regexp
      	../../regexp/exec.go:12:9: undefined: x
      	# regexp [regexp.test]
      	../../regexp/exec.go:12:9: undefined: x
      	FAIL	regexp [build failed]
      	FAIL	encoding/json [build failed]
      	$
      
      Change-Id: Ie325796f6c3cf0e23f306066be8e65a30cb6b939
      Reviewed-on: https://go-review.googlesource.com/108155
      Run-TryBot: Russ Cox <rsc@golang.org>
      Reviewed-by: 's avatarBryan C. Mills <bcmills@google.com>
      1a64025f
    • Russ Cox's avatar
      cmd/go: add go list -test to describe test binaries · 296e6765
      Russ Cox authored
      Tools should be able to ask cmd/go about the dependency
      graph for test binaries instead of reinventing it themselves.
      Allow them to do so, with the new list -test flag.
      
      This also fixes and tests for a bug introduced in CL 104315
      that was not properly splitting dependencies on the path
      between package main and the package being tested.
      
      Change-Id: I29eb454c82893f5ee70252aaaecd9fa376eaf3c8
      Reviewed-on: https://go-review.googlesource.com/107916
      Run-TryBot: Russ Cox <rsc@golang.org>
      Reviewed-by: 's avatarBryan C. Mills <bcmills@google.com>
      296e6765
  2. 25 Apr, 2018 22 commits
    • Josh Bleecher Snyder's avatar
      cmd/compile: use intrinsic for LeadingZeros8 on amd64 · c5f0104d
      Josh Bleecher Snyder authored
      The previous change sped up the pure computation form of LeadingZeros8.
      This places it somewhat close to the table lookup form.
      Depending on something that varies from toolchain to toolchain
      (alignment, perhaps?), the slowdown from ditching the table lookup
      is either 20% or 5%.
      
      This benchmark is the best case scenario for the table lookup:
      It is in the L1 cache already.
      
      I think we're close enough that we can switch to the computational version,
      and trust that the memory effects and binary size savings will be worth it.
      
      Code:
      
      func f8(x uint8)   { z = bits.LeadingZeros8(x) }
      
      Before:
      
      "".f8 STEXT nosplit size=34 args=0x8 locals=0x0
      	0x0000 00000 (x.go:7)	TEXT	"".f8(SB), NOSPLIT, $0-8
      	0x0000 00000 (x.go:7)	FUNCDATA	$0, gclocals·2a5305abe05176240e61b8620e19a815(SB)
      	0x0000 00000 (x.go:7)	FUNCDATA	$1, gclocals·33cdeccccebe80329f1fdbee7f5874cb(SB)
      	0x0000 00000 (x.go:7)	MOVBLZX	"".x+8(SP), AX
      	0x0005 00005 (x.go:7)	MOVBLZX	AL, AX
      	0x0008 00008 (x.go:7)	LEAQ	math/bits.len8tab(SB), CX
      	0x000f 00015 (x.go:7)	MOVBLZX	(CX)(AX*1), AX
      	0x0013 00019 (x.go:7)	ADDQ	$-8, AX
      	0x0017 00023 (x.go:7)	NEGQ	AX
      	0x001a 00026 (x.go:7)	MOVQ	AX, "".z(SB)
      	0x0021 00033 (x.go:7)	RET
      
      After:
      
      "".f8 STEXT nosplit size=30 args=0x8 locals=0x0
      	0x0000 00000 (x.go:7)	TEXT	"".f8(SB), NOSPLIT, $0-8
      	0x0000 00000 (x.go:7)	FUNCDATA	$0, gclocals·2a5305abe05176240e61b8620e19a815(SB)
      	0x0000 00000 (x.go:7)	FUNCDATA	$1, gclocals·33cdeccccebe80329f1fdbee7f5874cb(SB)
      	0x0000 00000 (x.go:7)	MOVBLZX	"".x+8(SP), AX
      	0x0005 00005 (x.go:7)	MOVBLZX	AL, AX
      	0x0008 00008 (x.go:7)	LEAL	1(AX)(AX*1), AX
      	0x000c 00012 (x.go:7)	BSRL	AX, AX
      	0x000f 00015 (x.go:7)	ADDQ	$-8, AX
      	0x0013 00019 (x.go:7)	NEGQ	AX
      	0x0016 00022 (x.go:7)	MOVQ	AX, "".z(SB)
      	0x001d 00029 (x.go:7)	RET
      
      Change-Id: Icc7db50a7820fb9a3da8a816d6b6940d7f8e193e
      Reviewed-on: https://go-review.googlesource.com/108942
      Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
      TryBot-Result: Gobot Gobot <gobot@golang.org>
      Reviewed-by: 's avatarKeith Randall <khr@golang.org>
      c5f0104d
    • Josh Bleecher Snyder's avatar
      cmd/compile: optimize LeadingZeros(16|32) on amd64 · 1d321ada
      Josh Bleecher Snyder authored
      Introduce Len8 and Len16 ops and provide optimized lowerings for them.
      amd64 only for this CL, although it wouldn't surprise me
      if other architectures also admit of optimized lowerings.
      
      Also use and optimize the Len32 lowering, along the same lines.
      
      Leave Len8 unused for the moment; a subsequent CL will enable it.
      
      For 16 and 32 bits, this leads to a speed-up.
      
      name              old time/op  new time/op  delta
      LeadingZeros16-8  1.42ns ± 5%  1.23ns ± 5%  -13.42%  (p=0.000 n=20+20)
      LeadingZeros32-8  1.25ns ± 5%  1.03ns ± 5%  -17.63%  (p=0.000 n=20+16)
      
      Code:
      
      func f16(x uint16) { z = bits.LeadingZeros16(x) }
      func f32(x uint32) { z = bits.LeadingZeros32(x) }
      
      Before:
      
      "".f16 STEXT nosplit size=38 args=0x8 locals=0x0
      	0x0000 00000 (x.go:8)	TEXT	"".f16(SB), NOSPLIT, $0-8
      	0x0000 00000 (x.go:8)	FUNCDATA	$0, gclocals·2a5305abe05176240e61b8620e19a815(SB)
      	0x0000 00000 (x.go:8)	FUNCDATA	$1, gclocals·33cdeccccebe80329f1fdbee7f5874cb(SB)
      	0x0000 00000 (x.go:8)	MOVWLZX	"".x+8(SP), AX
      	0x0005 00005 (x.go:8)	MOVWLZX	AX, AX
      	0x0008 00008 (x.go:8)	BSRQ	AX, AX
      	0x000c 00012 (x.go:8)	MOVQ	$-1, CX
      	0x0013 00019 (x.go:8)	CMOVQEQ	CX, AX
      	0x0017 00023 (x.go:8)	ADDQ	$-15, AX
      	0x001b 00027 (x.go:8)	NEGQ	AX
      	0x001e 00030 (x.go:8)	MOVQ	AX, "".z(SB)
      	0x0025 00037 (x.go:8)	RET
      
      "".f32 STEXT nosplit size=34 args=0x8 locals=0x0
      	0x0000 00000 (x.go:9)	TEXT	"".f32(SB), NOSPLIT, $0-8
      	0x0000 00000 (x.go:9)	FUNCDATA	$0, gclocals·2a5305abe05176240e61b8620e19a815(SB)
      	0x0000 00000 (x.go:9)	FUNCDATA	$1, gclocals·33cdeccccebe80329f1fdbee7f5874cb(SB)
      	0x0000 00000 (x.go:9)	MOVL	"".x+8(SP), AX
      	0x0004 00004 (x.go:9)	BSRQ	AX, AX
      	0x0008 00008 (x.go:9)	MOVQ	$-1, CX
      	0x000f 00015 (x.go:9)	CMOVQEQ	CX, AX
      	0x0013 00019 (x.go:9)	ADDQ	$-31, AX
      	0x0017 00023 (x.go:9)	NEGQ	AX
      	0x001a 00026 (x.go:9)	MOVQ	AX, "".z(SB)
      	0x0021 00033 (x.go:9)	RET
      
      After:
      
      "".f16 STEXT nosplit size=30 args=0x8 locals=0x0
      	0x0000 00000 (x.go:8)	TEXT	"".f16(SB), NOSPLIT, $0-8
      	0x0000 00000 (x.go:8)	FUNCDATA	$0, gclocals·2a5305abe05176240e61b8620e19a815(SB)
      	0x0000 00000 (x.go:8)	FUNCDATA	$1, gclocals·33cdeccccebe80329f1fdbee7f5874cb(SB)
      	0x0000 00000 (x.go:8)	MOVWLZX	"".x+8(SP), AX
      	0x0005 00005 (x.go:8)	MOVWLZX	AX, AX
      	0x0008 00008 (x.go:8)	LEAL	1(AX)(AX*1), AX
      	0x000c 00012 (x.go:8)	BSRL	AX, AX
      	0x000f 00015 (x.go:8)	ADDQ	$-16, AX
      	0x0013 00019 (x.go:8)	NEGQ	AX
      	0x0016 00022 (x.go:8)	MOVQ	AX, "".z(SB)
      	0x001d 00029 (x.go:8)	RET
      
      "".f32 STEXT nosplit size=28 args=0x8 locals=0x0
      	0x0000 00000 (x.go:9)	TEXT	"".f32(SB), NOSPLIT, $0-8
      	0x0000 00000 (x.go:9)	FUNCDATA	$0, gclocals·2a5305abe05176240e61b8620e19a815(SB)
      	0x0000 00000 (x.go:9)	FUNCDATA	$1, gclocals·33cdeccccebe80329f1fdbee7f5874cb(SB)
      	0x0000 00000 (x.go:9)	MOVL	"".x+8(SP), AX
      	0x0004 00004 (x.go:9)	LEAQ	1(AX)(AX*1), AX
      	0x0009 00009 (x.go:9)	BSRQ	AX, AX
      	0x000d 00013 (x.go:9)	ADDQ	$-32, AX
      	0x0011 00017 (x.go:9)	NEGQ	AX
      	0x0014 00020 (x.go:9)	MOVQ	AX, "".z(SB)
      	0x001b 00027 (x.go:9)	RET
      
      Change-Id: I6c93c173752a7bfdeab8be30777ae05a736e1f4b
      Reviewed-on: https://go-review.googlesource.com/108941
      Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
      TryBot-Result: Gobot Gobot <gobot@golang.org>
      Reviewed-by: 's avatarGiovanni Bajo <rasky@develer.com>
      Reviewed-by: 's avatarKeith Randall <khr@golang.org>
      1d321ada
    • Josh Bleecher Snyder's avatar
      cmd/compile: optimize TrailingZeros(8|16) on amd64 · 54dbab52
      Josh Bleecher Snyder authored
      Introduce Ctz8 and Ctz16 ops and provide optimized lowerings for them.
      amd64 only for this CL, although it wouldn't surprise me
      if other architectures also admit of optimized lowerings.
      
      name               old time/op  new time/op  delta
      TrailingZeros8-8   1.33ns ± 6%  0.84ns ± 3%  -36.90%  (p=0.000 n=20+20)
      TrailingZeros16-8  1.26ns ± 5%  0.84ns ± 5%  -33.50%  (p=0.000 n=20+18)
      
      Code:
      
      func f8(x uint8)   { z = bits.TrailingZeros8(x) }
      func f16(x uint16) { z = bits.TrailingZeros16(x) }
      
      Before:
      
      "".f8 STEXT nosplit size=34 args=0x8 locals=0x0
      	0x0000 00000 (x.go:7)	TEXT	"".f8(SB), NOSPLIT, $0-8
      	0x0000 00000 (x.go:7)	FUNCDATA	$0, gclocals·2a5305abe05176240e61b8620e19a815(SB)
      	0x0000 00000 (x.go:7)	FUNCDATA	$1, gclocals·33cdeccccebe80329f1fdbee7f5874cb(SB)
      	0x0000 00000 (x.go:7)	MOVBLZX	"".x+8(SP), AX
      	0x0005 00005 (x.go:7)	MOVBLZX	AL, AX
      	0x0008 00008 (x.go:7)	BTSQ	$8, AX
      	0x000d 00013 (x.go:7)	BSFQ	AX, AX
      	0x0011 00017 (x.go:7)	MOVL	$64, CX
      	0x0016 00022 (x.go:7)	CMOVQEQ	CX, AX
      	0x001a 00026 (x.go:7)	MOVQ	AX, "".z(SB)
      	0x0021 00033 (x.go:7)	RET
      
      "".f16 STEXT nosplit size=34 args=0x8 locals=0x0
      	0x0000 00000 (x.go:8)	TEXT	"".f16(SB), NOSPLIT, $0-8
      	0x0000 00000 (x.go:8)	FUNCDATA	$0, gclocals·2a5305abe05176240e61b8620e19a815(SB)
      	0x0000 00000 (x.go:8)	FUNCDATA	$1, gclocals·33cdeccccebe80329f1fdbee7f5874cb(SB)
      	0x0000 00000 (x.go:8)	MOVWLZX	"".x+8(SP), AX
      	0x0005 00005 (x.go:8)	MOVWLZX	AX, AX
      	0x0008 00008 (x.go:8)	BTSQ	$16, AX
      	0x000d 00013 (x.go:8)	BSFQ	AX, AX
      	0x0011 00017 (x.go:8)	MOVL	$64, CX
      	0x0016 00022 (x.go:8)	CMOVQEQ	CX, AX
      	0x001a 00026 (x.go:8)	MOVQ	AX, "".z(SB)
      	0x0021 00033 (x.go:8)	RET
      
      After:
      
      "".f8 STEXT nosplit size=20 args=0x8 locals=0x0
      	0x0000 00000 (x.go:7)	TEXT	"".f8(SB), NOSPLIT, $0-8
      	0x0000 00000 (x.go:7)	FUNCDATA	$0, gclocals·2a5305abe05176240e61b8620e19a815(SB)
      	0x0000 00000 (x.go:7)	FUNCDATA	$1, gclocals·33cdeccccebe80329f1fdbee7f5874cb(SB)
      	0x0000 00000 (x.go:7)	MOVBLZX	"".x+8(SP), AX
      	0x0005 00005 (x.go:7)	BTSL	$8, AX
      	0x0009 00009 (x.go:7)	BSFL	AX, AX
      	0x000c 00012 (x.go:7)	MOVQ	AX, "".z(SB)
      	0x0013 00019 (x.go:7)	RET
      
      "".f16 STEXT nosplit size=20 args=0x8 locals=0x0
      	0x0000 00000 (x.go:8)	TEXT	"".f16(SB), NOSPLIT, $0-8
      	0x0000 00000 (x.go:8)	FUNCDATA	$0, gclocals·2a5305abe05176240e61b8620e19a815(SB)
      	0x0000 00000 (x.go:8)	FUNCDATA	$1, gclocals·33cdeccccebe80329f1fdbee7f5874cb(SB)
      	0x0000 00000 (x.go:8)	MOVWLZX	"".x+8(SP), AX
      	0x0005 00005 (x.go:8)	BTSL	$16, AX
      	0x0009 00009 (x.go:8)	BSFL	AX, AX
      	0x000c 00012 (x.go:8)	MOVQ	AX, "".z(SB)
      	0x0013 00019 (x.go:8)	RET
      
      Change-Id: I0551e357348de2b724737d569afd6ac9f5c3aa11
      Reviewed-on: https://go-review.googlesource.com/108940
      Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
      TryBot-Result: Gobot Gobot <gobot@golang.org>
      Reviewed-by: 's avatarGiovanni Bajo <rasky@develer.com>
      Reviewed-by: 's avatarKeith Randall <khr@golang.org>
      54dbab52
    • Russ Cox's avatar
      cmd/go/internal/load: split test logic out of pkg.go into test.go · 90083e65
      Russ Cox authored
      It's going to grow.
      
      Change-Id: I4f5d3cce6e03250508d1ae0981a6d82a4192ae31
      Reviewed-on: https://go-review.googlesource.com/107915
      Run-TryBot: Russ Cox <rsc@golang.org>
      Reviewed-by: 's avatarBryan C. Mills <bcmills@google.com>
      90083e65
    • Russ Cox's avatar
      cmd/go: add go list -deps · 90e860f1
      Russ Cox authored
      This gives an easy way to query properties of all the deps
      of a set of packages, in a single go list invocation.
      Go list has already done the hard work of loading these
      packages, so exposing them is more efficient than
      requiring a second invocation.
      
      This will be helpful for tools asking cmd/go about build
      information.
      
      Change-Id: I90798e386246b24aad92dd13cb9e3788c7d30e91
      Reviewed-on: https://go-review.googlesource.com/107776
      Run-TryBot: Russ Cox <rsc@golang.org>
      TryBot-Result: Gobot Gobot <gobot@golang.org>
      Reviewed-by: 's avatarBryan C. Mills <bcmills@google.com>
      90e860f1
    • Ian Lance Taylor's avatar
      misc/cgo/test: log error value in testSigprocmask · 9c9ed9aa
      Ian Lance Taylor authored
      The test has been flaky, probably due to EAGAIN, but let's find out
      for sure.
      
      Updates #25078
      
      Change-Id: I5a5b14bfc52cb43f25f07ca7d207b61ae9d4f944
      Reviewed-on: https://go-review.googlesource.com/109359
      Run-TryBot: Ian Lance Taylor <iant@golang.org>
      Reviewed-by: 's avatarBryan C. Mills <bcmills@google.com>
      9c9ed9aa
    • Russ Cox's avatar
      cmd/compile: fix format error · d3ff5090
      Russ Cox authored
      Found by pending CL to make cmd/vet auto-detect printf wrappers.
      
      Change-Id: I6b5ba8f9c301dd2d7086c152cf2e54a68b012208
      Reviewed-on: https://go-review.googlesource.com/109345
      Run-TryBot: Russ Cox <rsc@golang.org>
      Reviewed-by: 's avatarRobert Griesemer <gri@golang.org>
      TryBot-Result: Gobot Gobot <gobot@golang.org>
      d3ff5090
    • Russ Cox's avatar
      encoding/base64: fix format error · 50a58396
      Russ Cox authored
      Found by pending CL to make cmd/vet auto-detect printf wrappers.
      
      Change-Id: I2ad06647b7b41cf68859820a60eeac2e689ca2e6
      Reviewed-on: https://go-review.googlesource.com/109344
      Run-TryBot: Russ Cox <rsc@golang.org>
      Reviewed-by: 's avatarRobert Griesemer <gri@golang.org>
      TryBot-Result: Gobot Gobot <gobot@golang.org>
      50a58396
    • Russ Cox's avatar
      go/types: fix format errors · 932794cb
      Russ Cox authored
      Found by pending CL to make cmd/vet auto-detect printf wrappers.
      
      Change-Id: I1928a5bcd7885cdd950ce81b7d0ba07fbad3bf88
      Reviewed-on: https://go-review.googlesource.com/109343
      Run-TryBot: Russ Cox <rsc@golang.org>
      Reviewed-by: 's avatarRobert Griesemer <gri@golang.org>
      TryBot-Result: Gobot Gobot <gobot@golang.org>
      932794cb
    • Russ Cox's avatar
      cmd/go: fix go list .Stale computation · 9e0e6981
      Russ Cox authored
      If X depends on Y and X was installed but Y is only present in the cache
      (as happens when you "go install X") then we should report X as up-to-date,
      not as stale.
      
      This applies whether X is a package or a main binary.
      
      Fixes #24558.
      Fixes #23818.
      
      Change-Id: I26a0b375b1f7f7ac909cc0db68e92f4e04529208
      Reviewed-on: https://go-review.googlesource.com/107957
      Run-TryBot: Russ Cox <rsc@golang.org>
      TryBot-Result: Gobot Gobot <gobot@golang.org>
      Reviewed-by: 's avatarBryan C. Mills <bcmills@google.com>
      9e0e6981
    • Matthew Dempsky's avatar
      cmd/compile/internal/types: remove Field.Funarg · 7500b299
      Matthew Dempsky authored
      Passes toolstash-check.
      
      Change-Id: Idc00f15e369cad62cb8f7a09fd0ef09abd3fcdef
      Reviewed-on: https://go-review.googlesource.com/109356
      Run-TryBot: Matthew Dempsky <mdempsky@google.com>
      Reviewed-by: 's avatarBrad Fitzpatrick <bradfitz@golang.org>
      TryBot-Result: Gobot Gobot <gobot@golang.org>
      7500b299
    • Robert Griesemer's avatar
      go/types: use correct (file) scopes when computing interface method sets · 73becbf9
      Robert Griesemer authored
      This was already partially fixed by commit 99843e22
      (https://go-review.googlesource.com/c/go/+/96376); but
      we missed a couple of places where we also need to
      propagate the scope.
      
      Fixes #25008.
      
      Change-Id: I041fa74d1f6d3b5a8edb922efa126ff1dacd7900
      Reviewed-on: https://go-review.googlesource.com/109139Reviewed-by: 's avatarAlan Donovan <adonovan@google.com>
      73becbf9
    • Russ Cox's avatar
      cmd/go: avoid infinite loop in go list -json -e on import cycle · f2df0ec7
      Russ Cox authored
      Don't chase import cycles forever preparing list JSON.
      
      Fixes #24086.
      
      Change-Id: Ia1139d0c8d813d068c367a8baee59d240a545617
      Reviewed-on: https://go-review.googlesource.com/108016
      Run-TryBot: Russ Cox <rsc@golang.org>
      TryBot-Result: Gobot Gobot <gobot@golang.org>
      Reviewed-by: 's avatarBryan C. Mills <bcmills@google.com>
      f2df0ec7
    • Ilya Tocar's avatar
      cmd/compile/internal/ssa: tweak branchelim cost model on amd64 · 25813f9f
      Ilya Tocar authored
      Currently branchelim is too aggressive in converting branches to
      conditinal movs. On most x86 cpus resulting cmov* are more expensive than
      most simple instructions, because they have a latency of 2, instead of 1,
      So by teaching branchelim to limit number of CondSelects and consider possible
      need to recalculate flags, we can archive huge speed-ups (fix big regressions).
      In package strings:
      
      ToUpper/#00-6                              10.9ns ± 1%  11.8ns ± 1%   +8.29%  (p=0.000 n=10+10)
      ToUpper/ONLYUPPER-6                        27.9ns ± 0%  27.8ns ± 1%     ~     (p=0.106 n=9+10)
      ToUpper/abc-6                              90.3ns ± 2%  90.3ns ± 1%     ~     (p=0.956 n=10+10)
      ToUpper/AbC123-6                            110ns ± 1%   113ns ± 2%   +3.19%  (p=0.000 n=10+10)
      ToUpper/azAZ09_-6                           109ns ± 2%   110ns ± 1%     ~     (p=0.174 n=10+10)
      ToUpper/longStrinGwitHmixofsmaLLandcAps-6   228ns ± 1%   233ns ± 2%   +2.11%  (p=0.000 n=10+10)
      ToUpper/longɐstringɐwithɐnonasciiⱯchars-6   907ns ± 1%   709ns ± 2%  -21.85%  (p=0.000 n=10+10)
      ToUpper/ɐɐɐɐɐ-6                             793ns ± 2%   562ns ± 2%  -29.06%  (p=0.000 n=10+10)
      
      In fmt:
      
      SprintfQuoteString-6   272ns ± 2%   195ns ± 4%  -28.39%  (p=0.000 n=10+10)
      
      And in archive/zip:
      
      CompressedZipGarbage-6       4.00ms ± 0%    4.03ms ± 0%   +0.71%  (p=0.000 n=10+10)
      Zip64Test-6                  27.5ms ± 1%    24.2ms ± 0%  -12.01%  (p=0.000 n=10+10)
      Zip64TestSizes/4096-6        10.4µs ±12%    10.7µs ± 8%     ~     (p=0.068 n=10+8)
      Zip64TestSizes/1048576-6     79.0µs ± 3%    70.2µs ± 2%  -11.14%  (p=0.000 n=10+10)
      Zip64TestSizes/67108864-6    4.64ms ± 1%    4.11ms ± 1%  -11.43%  (p=0.000 n=10+10)
      
      As far as I can tell, no cases with significant gain from cmov have regressed.
      
      On go1 it looks like most changes are unrelated, but I've verified that
      TimeFormat really switched from cmov to branch in a hot spot.
      Fill results below:
      
      name                     old time/op    new time/op    delta
      BinaryTree17-6              4.42s ± 1%     4.44s ± 1%    ~     (p=0.075 n=10+10)
      Fannkuch11-6                4.23s ± 0%     4.18s ± 0%  -1.16%  (p=0.000 n=8+10)
      FmtFprintfEmpty-6          67.5ns ± 2%    67.5ns ± 0%    ~     (p=0.950 n=10+7)
      FmtFprintfString-6          117ns ± 2%     119ns ± 1%  +1.07%  (p=0.045 n=9+10)
      FmtFprintfInt-6             122ns ± 0%     123ns ± 2%    ~     (p=0.825 n=8+10)
      FmtFprintfIntInt-6          188ns ± 1%     187ns ± 1%  -0.85%  (p=0.001 n=10+10)
      FmtFprintfPrefixedInt-6     223ns ± 1%     226ns ± 1%  +1.40%  (p=0.000 n=9+10)
      FmtFprintfFloat-6           380ns ± 1%     379ns ± 0%    ~     (p=0.350 n=9+7)
      FmtManyArgs-6               784ns ± 0%     790ns ± 1%  +0.81%  (p=0.000 n=10+9)
      GobDecode-6                10.7ms ± 1%    10.8ms ± 0%  +0.68%  (p=0.000 n=10+10)
      GobEncode-6                8.95ms ± 0%    8.94ms ± 0%    ~     (p=0.436 n=10+10)
      Gzip-6                      378ms ± 0%     378ms ± 0%    ~     (p=0.696 n=8+10)
      Gunzip-6                   60.5ms ± 0%    60.9ms ± 0%  +0.73%  (p=0.000 n=8+10)
      HTTPClientServer-6          109µs ± 3%     111µs ± 2%  +2.53%  (p=0.000 n=10+10)
      JSONEncode-6               20.2ms ± 0%    20.2ms ± 0%    ~     (p=0.382 n=8+8)
      JSONDecode-6               85.9ms ± 1%    84.5ms ± 0%  -1.59%  (p=0.000 n=10+8)
      Mandelbrot200-6            6.89ms ± 0%    6.85ms ± 1%  -0.49%  (p=0.000 n=9+10)
      GoParse-6                  5.49ms ± 0%    5.40ms ± 0%  -1.63%  (p=0.000 n=8+10)
      RegexpMatchEasy0_32-6       126ns ± 1%     129ns ± 1%  +2.14%  (p=0.000 n=10+10)
      RegexpMatchEasy0_1K-6       320ns ± 1%     317ns ± 2%    ~     (p=0.089 n=10+10)
      RegexpMatchEasy1_32-6       119ns ± 2%     121ns ± 4%    ~     (p=0.591 n=10+10)
      RegexpMatchEasy1_1K-6       544ns ± 1%     541ns ± 0%  -0.67%  (p=0.020 n=8+8)
      RegexpMatchMedium_32-6      184ns ± 1%     184ns ± 1%    ~     (p=0.360 n=10+10)
      RegexpMatchMedium_1K-6     57.7µs ± 2%    58.3µs ± 1%  +1.12%  (p=0.022 n=10+10)
      RegexpMatchHard_32-6       2.72µs ± 5%    2.70µs ± 0%    ~     (p=0.166 n=10+8)
      RegexpMatchHard_1K-6       80.2µs ± 0%    81.0µs ± 0%  +1.01%  (p=0.000 n=8+10)
      Revcomp-6                   607ms ± 0%     601ms ± 2%  -1.00%  (p=0.006 n=8+10)
      Template-6                 93.1ms ± 1%    92.6ms ± 0%  -0.56%  (p=0.000 n=9+9)
      TimeParse-6                 472ns ± 0%     470ns ± 0%  -0.28%  (p=0.001 n=9+9)
      TimeFormat-6                546ns ± 0%     511ns ± 0%  -6.41%  (p=0.001 n=7+7)
      [Geo mean]                 76.4µs         76.3µs       -0.12%
      
      name                     old speed      new speed      delta
      GobDecode-6              71.5MB/s ± 1%  71.1MB/s ± 0%  -0.68%  (p=0.000 n=10+10)
      GobEncode-6              85.8MB/s ± 0%  85.8MB/s ± 0%    ~     (p=0.425 n=10+10)
      Gzip-6                   51.3MB/s ± 0%  51.3MB/s ± 0%    ~     (p=0.680 n=8+10)
      Gunzip-6                  321MB/s ± 0%   318MB/s ± 0%  -0.73%  (p=0.000 n=8+10)
      JSONEncode-6             95.9MB/s ± 0%  96.0MB/s ± 0%    ~     (p=0.367 n=8+8)
      JSONDecode-6             22.6MB/s ± 1%  22.9MB/s ± 0%  +1.62%  (p=0.000 n=10+8)
      GoParse-6                10.6MB/s ± 0%  10.7MB/s ± 0%  +1.64%  (p=0.000 n=8+10)
      RegexpMatchEasy0_32-6     252MB/s ± 1%   247MB/s ± 1%  -2.22%  (p=0.000 n=10+10)
      RegexpMatchEasy0_1K-6    3.19GB/s ± 1%  3.22GB/s ± 2%    ~     (p=0.105 n=10+10)
      RegexpMatchEasy1_32-6     267MB/s ± 2%   264MB/s ± 4%    ~     (p=0.481 n=10+10)
      RegexpMatchEasy1_1K-6    1.88GB/s ± 1%  1.89GB/s ± 0%  +0.62%  (p=0.038 n=8+8)
      RegexpMatchMedium_32-6   5.41MB/s ± 2%  5.43MB/s ± 0%    ~     (p=0.339 n=10+8)
      RegexpMatchMedium_1K-6   17.8MB/s ± 1%  17.6MB/s ± 1%  -1.12%  (p=0.029 n=10+10)
      RegexpMatchHard_32-6     11.8MB/s ± 5%  11.8MB/s ± 0%    ~     (p=0.163 n=10+8)
      RegexpMatchHard_1K-6     12.8MB/s ± 0%  12.6MB/s ± 0%  -1.06%  (p=0.000 n=7+10)
      Revcomp-6                 419MB/s ± 0%   423MB/s ± 2%  +1.02%  (p=0.006 n=8+10)
      Template-6               20.9MB/s ± 0%  21.0MB/s ± 0%  +0.53%  (p=0.000 n=8+8)
      [Geo mean]               77.0MB/s       77.0MB/s       +0.05%
      
      diff --git a/src/cmd/compile/internal/ssa/branchelim.go b/src/cmd/compile/internal/ssa/branchelim.go
      
      Change-Id: Ibdffa9ea9b4c72668617ce3202ec4a83a1cd59be
      Reviewed-on: https://go-review.googlesource.com/107936
      Run-TryBot: Ilya Tocar <ilya.tocar@intel.com>
      TryBot-Result: Gobot Gobot <gobot@golang.org>
      Reviewed-by: 's avatarKeith Randall <khr@golang.org>
      25813f9f
    • Russ Cox's avatar
      cmd/vet/all: fix whitelist for CL 108557 · 01a74875
      Russ Cox authored
      Change-Id: I831775db5de92d211495acc012fc4366c7c84851
      Reviewed-on: https://go-review.googlesource.com/109335
      Run-TryBot: Russ Cox <rsc@golang.org>
      Reviewed-by: 's avatarRuss Cox <rsc@golang.org>
      01a74875
    • Daniel Martí's avatar
      cmd/vet: use type information in isLocalType · 85146fab
      Daniel Martí authored
      Now that vet always has type information, there's no reason to use
      string handling on type names to gather information about them, such as
      whether or not they are a local type.
      
      The semantics remain the same - the only difference should be that the
      implementation is less fragile and simpler.
      
      Change-Id: I71386b4196922e4c9f2653d90abc382efbf01b3c
      Reviewed-on: https://go-review.googlesource.com/95915
      Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
      TryBot-Result: Gobot Gobot <gobot@golang.org>
      Reviewed-by: 's avatarAlan Donovan <adonovan@google.com>
      85146fab
    • Martin Möhrmann's avatar
      internal/cpu: remove redundant build tag · 74f9432b
      Martin Möhrmann authored
      The file name suffix arm64 already limits the file to be build only on arm64.
      
      Change-Id: I33db713041b6dec9eb00889bac3b54c727e90743
      Reviewed-on: https://go-review.googlesource.com/108986
      Run-TryBot: Martin Möhrmann <moehrmann@google.com>
      Reviewed-by: 's avatarBrad Fitzpatrick <bradfitz@golang.org>
      TryBot-Result: Gobot Gobot <gobot@golang.org>
      74f9432b
    • Russ Cox's avatar
      sync: hide test of misuse of Cond from vet · eca7a134
      Russ Cox authored
      The test wants to check that copies of Cond are detected at runtime.
      Make a copy that isn't detected by vet at compile time.
      
      Change-Id: I933ab1003585f75ba96723563107f1ba8126cb72
      Reviewed-on: https://go-review.googlesource.com/108557Reviewed-by: 's avatarIan Lance Taylor <iant@golang.org>
      eca7a134
    • Russ Cox's avatar
      doc: update "go get" HTTPS answer to mention .netrc · 09d36a81
      Russ Cox authored
      The existing text makes it seem like there's no way
      to use GitHub over HTTPS. There is. Explain that.
      
      Also, the existing text suggests explicit checkout into $GOPATH,
      which is not going to work in the new module world.
      Drop that alternative.
      
      Also, the existing text uses pushInsteadOf instead of insteadOf,
      which would have the effect of being able to push to a private
      repo but not clone it in the first place. That seems not helpful,
      so suggest insteadOf instead.
      
      Fixes #18927.
      
      Change-Id: Ic358b66f88064b53067d174a2a1591ac8bf96c88
      Reviewed-on: https://go-review.googlesource.com/107775
      Run-TryBot: Russ Cox <rsc@golang.org>
      Reviewed-by: 's avatarIan Lance Taylor <iant@golang.org>
      09d36a81
    • Russ Cox's avatar
      os: fix type check error in benchmark · e9bc0c5d
      Russ Cox authored
      Previously, 's' was only written to, never read,
      which is disallowed by the spec. cmd/compile
      has a bug where it doesn't notice this when a
      closure is involved, but go/types does notice,
      which was making "go vet" fail.
      
      This CL moves the variable into the closure
      and also makes sure to use it.
      
      Change-Id: I2d83fb6b5c1c9018df03533e966cbdf455f83bf9
      Reviewed-on: https://go-review.googlesource.com/108556
      Run-TryBot: Russ Cox <rsc@golang.org>
      Reviewed-by: 's avatarIan Lance Taylor <iant@golang.org>
      e9bc0c5d
    • Ian Lance Taylor's avatar
      cmd/cgo: don't use absolute paths in the export header file · be012e1e
      Ian Lance Taylor authored
      We were using absolute paths in the #line directives in the export
      header file. This makes the header file change if you move GOPATH.
      The absolute paths aren't helpful for the final user, which is some C
      program elsewhere.
      
      Fixes #24945
      
      Change-Id: I2da32c9b477df578bd5087435a03fe97abe462e3
      Reviewed-on: https://go-review.googlesource.com/108315
      Run-TryBot: Ian Lance Taylor <iant@golang.org>
      TryBot-Result: Gobot Gobot <gobot@golang.org>
      Reviewed-by: 's avatarBrad Fitzpatrick <bradfitz@golang.org>
      be012e1e
    • Matthew Dempsky's avatar
      go/types: fix lhs/rhs mixup in docs · a5f19812
      Matthew Dempsky authored
      Change-Id: Ifd51636c9254de51b8a21371d7507a9481bcca0a
      Reviewed-on: https://go-review.googlesource.com/109142Reviewed-by: 's avatarRobert Griesemer <gri@golang.org>
      a5f19812
  3. 24 Apr, 2018 16 commits
    • Keith Randall's avatar
      cmd/compile: update SSA TODO file · ae26d57f
      Keith Randall authored
      Get rid of a bunch of stuff we've already done.
      
      Change-Id: Ibae4be7535ddb58590a072a2390c5f3e948c2fd7
      Reviewed-on: https://go-review.googlesource.com/109136Reviewed-by: 's avatarBrad Fitzpatrick <bradfitz@golang.org>
      ae26d57f
    • Matthew Dempsky's avatar
      cmd/compile/internal/types: replace Type.Val with Type.Elem · 2083b5d6
      Matthew Dempsky authored
      This reduces the API surface of Type slightly (for #25056), but also
      makes it more consistent with the reflect and go/types APIs.
      
      Passes toolstash-check.
      
      Change-Id: Ief9a8eb461ae6e88895f347e2a1b7b8a62423222
      Reviewed-on: https://go-review.googlesource.com/109138
      Run-TryBot: Matthew Dempsky <mdempsky@google.com>
      TryBot-Result: Gobot Gobot <gobot@golang.org>
      Reviewed-by: 's avatarBrad Fitzpatrick <bradfitz@golang.org>
      2083b5d6
    • Matthew Dempsky's avatar
      cmd/compile/internal/types: remove ElemType wrapper · e10ee798
      Matthew Dempsky authored
      This was an artifact from when we had a separate ssa.Type interface to
      break circular dependency between packages ssa and gc. It's no longer
      needed now that package ssa directly uses package types.
      
      Change-Id: I6a93e5d79082815f7f0eb89507381969cc6cb403
      Reviewed-on: https://go-review.googlesource.com/109137
      Run-TryBot: Matthew Dempsky <mdempsky@google.com>
      TryBot-Result: Gobot Gobot <gobot@golang.org>
      Reviewed-by: 's avatarJosh Bleecher Snyder <josharian@gmail.com>
      e10ee798
    • Hana Kim's avatar
      cmd/trace: distinguish task endTimestamp and lastTimestamp · 011f6c5f
      Hana Kim authored
      A task may have other user annotation events after the task ends.
      So far, task.lastTimestamp returned the task end event if the
      event available. This change introduces task.endTimestamp for that
      and makes task.lastTimestamp returns the "last" seen event's timestamp
      if the task is ended.
      
      If the task is not ended, both returns the last timestamp of the entire
      trace assuming the task is still active.
      
      This fixes the task-oriented trace view mode not to drop user
      annotation instances when they appear outside a task's lifespan.
      Adds a test.
      
      Change-Id: Iba1062914f224edd521b9ee55c6cd5e180e55359
      Reviewed-on: https://go-review.googlesource.com/109175Reviewed-by: 's avatarHeschi Kreinick <heschi@google.com>
      011f6c5f
    • erifan01's avatar
      internal/bytealg: optimize IndexString on arm64 · d4e936cf
      erifan01 authored
      This CL adjusts the order of the branch instructions of the
      code to make it easier for the LIKELY branch to happen.
      
      Benchmarks:
      name                            old time/op    new time/op    delta
      pkg:strings goos:linux goarch:arm64
      IndexHard2-8                      2.17ms ± 1%    1.23ms ± 0%  -43.34%  (p=0.008 n=5+5)
      CountHard2-8                      2.13ms ± 1%    1.21ms ± 2%  -43.31%  (p=0.008 n=5+5)
      
      pkg:bytes goos:linux goarch:arm64
      IndexRune/4M-8                     661µs ±22%     513µs ± 0%  -22.32%  (p=0.008 n=5+5)
      IndexEasy/4M-8                     672µs ±23%     513µs ± 0%  -23.71%  (p=0.016 n=5+4)
      
      Change-Id: Ib96f095edf77747edc8a971e79f5c1428e5808ce
      Reviewed-on: https://go-review.googlesource.com/109015Reviewed-by: 's avatarCherry Zhang <cherryyz@google.com>
      Run-TryBot: Cherry Zhang <cherryyz@google.com>
      TryBot-Result: Gobot Gobot <gobot@golang.org>
      d4e936cf
    • Heschi Kreinick's avatar
      cmd/link: fix TestRuntimeTypeAttr on ppc64,solaris · 5d4267e4
      Heschi Kreinick authored
      For ppc64, skip -linkmode=external per
      https://go-review.googlesource.com/c/go/+/106775#message-f95b9bd716e3d9ebb3f47a50492cde9f2972e859
      
      For Solaris, apparently type.* isn't the same as runtime.types. I don't
      know why, but runtime.types is what goes into moduledata, and so it's
      definitely the more correct thing to use.
      
      Fixes: #24983
      
      Change-Id: I6b465ac7b8f91ce55a63acbd7fe76e4a2dbb6f22
      Reviewed-on: https://go-review.googlesource.com/108955
      Run-TryBot: Heschi Kreinick <heschi@google.com>
      Reviewed-by: 's avatarBrad Fitzpatrick <bradfitz@golang.org>
      TryBot-Result: Gobot Gobot <gobot@golang.org>
      5d4267e4
    • Josh Bleecher Snyder's avatar
      cmd/compile: improve regalloc live values debug printing · 3d6647d6
      Josh Bleecher Snyder authored
      Before:
      
      live values at end of each block
        b1: v3 v2 v7 avoid=0
        b2: v3 v13 avoid=81
        b3: v19[AX] v3 avoid=81
        b6: avoid=0
        b7: avoid=0
        b5: avoid=0
        b4: v3 v18 avoid=81
      
      After:
      
      live values at end of each block
        b1: v3 v2 v7
        b2: v3 v13 avoid=AX DI
        b3: v19[AX] v3 avoid=AX DI
        b6:
        b7:
        b5:
        b4: v3 v18 avoid=AX DI
      
      Change-Id: Ibec5c76a16151832b8d49a21c640699fdc9a9d28
      Reviewed-on: https://go-review.googlesource.com/109000
      Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
      TryBot-Result: Gobot Gobot <gobot@golang.org>
      Reviewed-by: 's avatarBrad Fitzpatrick <bradfitz@golang.org>
      3d6647d6
    • Hana Kim's avatar
      runtime/trace: add simple benchmarks for user annotation · 3bf16444
      Hana Kim authored
      Also, avoid Region creation when tracing is disabled.
      Unfortunate side-effect of this change is that we no longer trace
      pre-existing regions in tracing, but we can add the feature in
      the future when we find it useful and justifiable. Until then,
      let's avoid the overhead from this low-level api use as much as
      possible.
      
      goos: linux
      goarch: amd64
      pkg: runtime/trace
      
      // Trace disabled
      BenchmarkStartRegion-12 2000000000	         0.66 ns/op	       0 B/op	       0 allocs/op
      BenchmarkNewTask-12    	30000000	        40.4 ns/op	      56 B/op	       2 allocs/op
      
      // Trace enabled, -trace=/dev/null
      BenchmarkStartRegion-12  5000000	       287 ns/op	      32 B/op	       1 allocs/op
      BenchmarkNewTask-12    	 5000000	       283 ns/op	      56 B/op	       2 allocs/op
      
      Also, skip other tests if tracing is already enabled.
      
      Change-Id: Id3028d60b5642fcab4b09a74fd7d79361a3861e5
      Reviewed-on: https://go-review.googlesource.com/109115Reviewed-by: 's avatarPeter Weinberger <pjw@google.com>
      3bf16444
    • Hana Kim's avatar
      runtime/trace: rename "Span" with "Region" · c2d10243
      Hana Kim authored
      "Span" is a commonly used term in many distributed tracing systems
      (Dapper, OpenCensus, OpenTracing, ...). They use it to refer to a
      period of time, not necessarily tied into execution of underlying
      processor, thread, or goroutine, unlike the "Span" of runtime/trace
      package.
      
      Since distributed tracing and go runtime execution tracing are
      already similar enough to cause confusion, this CL attempts to avoid
      using the same word if possible.
      
      "Region" is being used in a certain tracing system to refer to a code
      region which is pretty close to what runtime/trace.Span currently
      refers to. So, replace that.
      https://software.intel.com/en-us/itc-user-and-reference-guide-defining-and-recording-functions-or-regions
      
      This CL also tweaks APIs a bit based on jbd and heschi's comments:
      
        NewContext -> NewTask
          and it now returns a Task object that exports End method.
      
        StartSpan -> StartRegion
          and it now returns a Region object that exports End method.
      
      Also, changed WithSpan to WithRegion and it now takes func() with no
      context. Another thought is to get rid of WithRegion. It is a nice
      concept but in practice, it seems problematic (a lot of code churn,
      and polluting stack trace). Already, the tracing concept is very low
      level, and we hope this API to be used with great care.
      
      Recommended usage will be
         defer trace.StartRegion(ctx, "someRegion").End()
      
      Left old APIs untouched in this CL. Once the usage of them are cleaned
      up, they will be removed in a separate CL.
      
      Change-Id: I73880635e437f3aad51314331a035dd1459b9f3a
      Reviewed-on: https://go-review.googlesource.com/108296
      Run-TryBot: Hyang-Ah Hana Kim <hyangah@gmail.com>
      TryBot-Result: Gobot Gobot <gobot@golang.org>
      Reviewed-by: 's avatarJBD <jbd@google.com>
      c2d10243
    • Ilya Tocar's avatar
      cmd/compile/internal/ssa: fix endless compile loop on AMD64 · fb017c60
      Ilya Tocar authored
      We currently rewrite
      (TESTQ (MOVQconst [c] x)) into (TESTQconst [c] x)
      and (TESTQconst [-1] x) into (TESTQ x x)
      if x is a (MOVQconst [-1]) we will be stuck in the endless rewrite loop.
      Don't perform the rewrite in such cases.
      
      Fixes #25006
      
      Change-Id: I77f561ba2605fc104f1e5d5c57f32e9d67a2c000
      Reviewed-on: https://go-review.googlesource.com/108879
      Run-TryBot: Ilya Tocar <ilya.tocar@intel.com>
      TryBot-Result: Gobot Gobot <gobot@golang.org>
      Reviewed-by: 's avatarKeith Randall <khr@golang.org>
      fb017c60
    • Hana (Hyang-Ah) Kim's avatar
      runtime/pprof: introduce "allocs" profile · cd037bce
      Hana (Hyang-Ah) Kim authored
      The Go's heap profile contains four kinds of samples
      (inuse_space, inuse_objects, alloc_space, and alloc_objects).
      The pprof tool by default chooses the inuse_space (the bytes
      of live, in-use objects). When analyzing the current memory
      usage the choice of inuse_space as the default may be useful,
      but in some cases, users are more interested in analyzing the
      total allocation statistics throughout the program execution.
      For example, when we analyze the memory profile from benchmark
      or program test run, we are more likely interested in the whole
      allocation history than the live heap snapshot at the end of
      the test or benchmark.
      
      The pprof tool provides flags to control which sample type
      to be used for analysis. However, it is one of the less-known
      features of pprof and we believe it's better to choose the
      right type of samples as the default when producing the profile.
      
      This CL introduces a new type of profile, "allocs", which is
      the same as the "heap" profile but marks the alloc_space
      as the default type unlike heap profiles that use inuse_space
      as the default type.
      
      'go test -memprofile=...' command is changed to use the new
      "allocs" profile type instead of the traditional "heap" profile.
      
      Fixes #24443
      
      Change-Id: I012dd4b6dcacd45644d7345509936b8380b6fbd9
      Reviewed-on: https://go-review.googlesource.com/102696
      Run-TryBot: Hyang-Ah Hana Kim <hyangah@gmail.com>
      Reviewed-by: 's avatarRuss Cox <rsc@golang.org>
      cd037bce
    • quasilyte's avatar
      cmd/internal/obj/x86: forbid mem args for MOV_DR and MOV_CR · 70c5839f
      quasilyte authored
      Memory arguments for debug/control register moves are a
      minefield for programmer: not useful, but can lead to errors.
      
      See referenced issue for detailed explanation.
      
      Fixes #24981
      
      Change-Id: I918e81cd4a8b1dfcfc9023cdfc3de45abe29e749
      Reviewed-on: https://go-review.googlesource.com/107075
      Run-TryBot: Iskander Sharipov <iskander.sharipov@intel.com>
      TryBot-Result: Gobot Gobot <gobot@golang.org>
      Reviewed-by: 's avatarCherry Zhang <cherryyz@google.com>
      70c5839f
    • isharipo's avatar
      cmd/compile/internal/ssa: add Op{SP,SB} type checks to check.go · cb44c8de
      isharipo authored
      gc/ssa.go initilizes SP and SB values with TUINTPTR type.
      Assign same type in SSA tests and modify check.go to catch
      mismatching types for those ops.
      
      This makes SSA tests more consistent.
      
      Change-Id: I798440d57d00fb949d1a0cd796759c9b82a934bd
      Reviewed-on: https://go-review.googlesource.com/106658
      Run-TryBot: Iskander Sharipov <iskander.sharipov@intel.com>
      TryBot-Result: Gobot Gobot <gobot@golang.org>
      Reviewed-by: 's avatarKeith Randall <khr@golang.org>
      cb44c8de
    • ludweeg's avatar
      crypto/md5: unnecessary conversion · d18f186b
      ludweeg authored
      Fixes go lint warning.
      
      Change-Id: I5a7485a4c8316b81e6aa50b95fe75e424f2fcedc
      Reviewed-on: https://go-review.googlesource.com/109055Reviewed-by: 's avatarBrad Fitzpatrick <bradfitz@golang.org>
      Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
      TryBot-Result: Gobot Gobot <gobot@golang.org>
      d18f186b
    • Andrei Tudor Călin's avatar
      net: add support for splice(2) in (*TCPConn).ReadFrom on Linux · f2316c27
      Andrei Tudor Călin authored
      This change adds support for the splice system call on Linux,
      for the purpose of optimizing (*TCPConn).ReadFrom by reducing
      copies of data from and to userspace. It does so by creating a
      temporary pipe and splicing data from the source connection to the
      pipe, then from the pipe to the destination connection. The pipe
      serves as an in-kernel buffer for the data transfer.
      
      No new API is added to package net, but a new Splice function is
      added to package internal/poll, because using splice requires help
      from the network poller. Users of the net package should benefit
      from the change transparently.
      
      This change only enables the optimization if the Reader in ReadFrom
      is a TCP connection. Since splice is a more general interface, it
      could, in theory, also be enabled if the Reader were a unix socket,
      or the read half of a pipe.
      
      However, benchmarks show that enabling it for unix sockets is most
      likely not a net performance gain. The tcp <- unix case is also
      fairly unlikely to be used very much by users of package net.
      
      Enabling the optimization for pipes is also problematic from an
      implementation perspective, since package net cannot easily get at
      the *poll.FD of an *os.File. A possible solution to this would be
      to dup the pipe file descriptor, register the duped descriptor with
      the network poller, and work on that *poll.FD instead of the original.
      However, this seems too intrusive, so it has not been done. If there
      was a clean way to do it, it would probably be worth doing, since
      splicing from a pipe to a socket can be done directly.
      
      Therefore, this patch only enables the optimization for what is likely
      the most common use case: tcp <- tcp.
      
      The following benchmark compares the performance of the previous
      userspace genericReadFrom code path to the new optimized code path.
      The sub-benchmarks represent chunk sizes used by the writer on the
      other end of the Reader passed to ReadFrom.
      
      benchmark                          old ns/op     new ns/op     delta
      BenchmarkTCPReadFrom/1024-4        4727          4954          +4.80%
      BenchmarkTCPReadFrom/2048-4        4389          4301          -2.01%
      BenchmarkTCPReadFrom/4096-4        4606          4534          -1.56%
      BenchmarkTCPReadFrom/8192-4        5219          4779          -8.43%
      BenchmarkTCPReadFrom/16384-4       8708          8008          -8.04%
      BenchmarkTCPReadFrom/32768-4       16349         14973         -8.42%
      BenchmarkTCPReadFrom/65536-4       35246         27406         -22.24%
      BenchmarkTCPReadFrom/131072-4      72920         52382         -28.17%
      BenchmarkTCPReadFrom/262144-4      149311        95094         -36.31%
      BenchmarkTCPReadFrom/524288-4      306704        181856        -40.71%
      BenchmarkTCPReadFrom/1048576-4     674174        357406        -46.99%
      
      benchmark                          old MB/s     new MB/s     speedup
      BenchmarkTCPReadFrom/1024-4        216.62       206.69       0.95x
      BenchmarkTCPReadFrom/2048-4        466.61       476.08       1.02x
      BenchmarkTCPReadFrom/4096-4        889.09       903.31       1.02x
      BenchmarkTCPReadFrom/8192-4        1569.40      1714.06      1.09x
      BenchmarkTCPReadFrom/16384-4       1881.42      2045.84      1.09x
      BenchmarkTCPReadFrom/32768-4       2004.18      2188.41      1.09x
      BenchmarkTCPReadFrom/65536-4       1859.38      2391.25      1.29x
      BenchmarkTCPReadFrom/131072-4      1797.46      2502.21      1.39x
      BenchmarkTCPReadFrom/262144-4      1755.69      2756.68      1.57x
      BenchmarkTCPReadFrom/524288-4      1709.42      2882.98      1.69x
      BenchmarkTCPReadFrom/1048576-4     1555.35      2933.84      1.89x
      
      Fixes #10948
      
      Change-Id: I3ce27f21f7adda8b696afdc48a91149998ae16a5
      Reviewed-on: https://go-review.googlesource.com/107715
      Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
      Run-TryBot: Ian Lance Taylor <iant@golang.org>
      TryBot-Result: Gobot Gobot <gobot@golang.org>
      Reviewed-by: 's avatarIan Lance Taylor <iant@golang.org>
      f2316c27
    • Wèi Cōngruì's avatar
      runtime: fix errno sign for epollctl on mips, mips64 and ppc64 · cc880923
      Wèi Cōngruì authored
      The caller of epollctl expects it to return a negative errno value,
      but it returns a positive errno value on mips, mips64 and ppc64.
      The change fixes this.
      
      Updates #23446
      
      Change-Id: Ie6372eca6c23de21964caaaa433c9a45ef93531e
      Reviewed-on: https://go-review.googlesource.com/89235Reviewed-by: 's avatarCarlos Eduardo Seo <cseo@linux.vnet.ibm.com>
      Reviewed-by: 's avatarIan Lance Taylor <iant@golang.org>
      Run-TryBot: Ian Lance Taylor <iant@golang.org>
      TryBot-Result: Gobot Gobot <gobot@golang.org>
      cc880923