Commits · 6dc9e31f5e86112737bb60e54b6f903929ca11d8 · Kirill Smelkov / go

03 Feb, 2017 14 commits

cmd/go: split out cmd/go/internal/base · 6dc9e31f

Russ Cox authored Jan 13, 2017

This is one CL in a long sequence of changes to break up the
go command from one package into a plausible group of packages.

This sequence is concerned only with moving code, not changing
or cleaning up code. There will still be more cleanup after this sequence.

The entire sequence will be submitted together: it is not a goal
for the tree to build at every step.

For #18653.

Change-Id: I7c5dde6e7fe4f390e6607303b4d42535c674eac3
Reviewed-on: https://go-review.googlesource.com/36193Reviewed-by: David Crawshaw <crawshaw@golang.org>

6dc9e31f

cmd/dist: move cmd/go z files to cmd/go/internal/cfg · b60e61ab

Russ Cox authored Jan 18, 2017

This is one CL in a long sequence of changes to break up the
go command from one package into a plausible group of packages.

This sequence is concerned only with moving code, not changing
or cleaning up code. There will still be more cleanup after this sequence.

The entire sequence will be submitted together: it is not a goal
for the tree to build at every step.

For #18653.

Change-Id: I6ee5b053683034ea9462a9a0a4ea4f5ad24fa5a1
Reviewed-on: https://go-review.googlesource.com/36192Reviewed-by: David Crawshaw <crawshaw@golang.org>

b60e61ab

cmd/go: split out cmd/go/internal/cfg · a918864c

Russ Cox authored Jan 13, 2017

This is one CL in a long sequence of changes to break up the
go command from one package into a plausible group of packages.

This sequence is concerned only with moving code, not changing
or cleaning up code. There will still be more cleanup after this sequence.

The entire sequence will be submitted together: it is not a goal
for the tree to build at every step.

For #18653.

Change-Id: Icb3f168ade91e7da5fcab89ac75b768daefff359
Reviewed-on: https://go-review.googlesource.com/36191Reviewed-by: David Crawshaw <crawshaw@golang.org>

a918864c

cmd/go: split out cmd/go/internal/str · 762eb408

Russ Cox authored Jan 13, 2017

This is one CL in a long sequence of changes to break up the
go command from one package into a plausible group of packages.

This sequence is concerned only with moving code, not changing
or cleaning up code. There will still be more cleanup after this sequence.

The entire sequence will be submitted together: it is not a goal
for the tree to build at every step.

For #18653.

Change-Id: I63f578f5ac99c707b599ac5659293c46b275567d
Reviewed-on: https://go-review.googlesource.com/36190Reviewed-by: David Crawshaw <crawshaw@golang.org>

762eb408

cmd/go: break a few dependencies · d9e6835b

Russ Cox authored Jan 13, 2017

This CL makes a few naming changes to break dependencies
between different parts of the go command, to make it easier
to split into different packages.

This is the first CL in a long sequence of changes to break up the
go command from one package into a plausible group of packages.

This sequence is concerned only with moving code, not changing
or cleaning up code. There will still be more cleanup after this sequence.

The entire sequence will be submitted together: it is not a goal
for the tree to build at every step.

For #18653.

Change-Id: I69a98b9ea48e61b1e1cda95273d29860b525415f
Reviewed-on: https://go-review.googlesource.com/36129Reviewed-by: David Crawshaw <crawshaw@golang.org>

d9e6835b

runtime: handle SIGPIPE in c-archive and c-shared programs · 78074f68

Elias Naur authored Jan 29, 2017

Before this CL, Go programs in c-archive or c-shared buildmodes
would not handle SIGPIPE. That leads to surprising behaviour where
writes on a closed pipe or socket would raise SIGPIPE and terminate
the program. This CL changes the Go runtime to handle
SIGPIPE regardless of buildmode. In addition, SIGPIPE from non-Go
code is forwarded.

This is a refinement of CL 32796 that fixes the case where a non-default
handler for SIGPIPE is installed by the host C program.

Fixes #17393

Change-Id: Ia41186e52c1ac209d0a594bae9904166ae7df7de
Reviewed-on: https://go-review.googlesource.com/35960
Run-TryBot: Elias Naur <elias.naur@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

78074f68

cmd/compile: make liveness more efficient · b612ab3a

Josh Bleecher Snyder authored Jan 14, 2017

When the number of variables in a function is very large,
liveness analysis gets less efficient, since every bit vector
is O(number of variables).

Improve the situation by returning a sparse representation
from progeffects. In all scenarios, progeffects either
returns a slice that is shared function-wide,
and which is usually small, or a slice that is guaranteed
to have at most three values.

Reduces compilation time for the code in #8225 Comment 1 by ~10%.
Minor effects on regular packages (below).

Passes toolstash -cmp.

Updates #8225

name old time/op new time/op delta
Template 215ms ± 2% 212ms ± 4% -1.31% (p=0.001 n=30+30)
Unicode 98.3ms ± 3% 98.4ms ± 5% ~ (p=0.971 n=30+30)
GoTypes 657ms ± 3% 651ms ± 2% -0.98% (p=0.001 n=30+27)
Compiler 2.78s ± 2% 2.77s ± 2% -0.60% (p=0.006 n=30+30)
Flate 130ms ± 4% 130ms ± 4% ~ (p=0.712 n=29+30)
GoParser 159ms ± 5% 158ms ± 3% ~ (p=0.331 n=29+30)
Reflect 406ms ± 3% 404ms ± 3% -0.69% (p=0.041 n=29+30)
Tar 117ms ± 4% 117ms ± 3% ~ (p=0.886 n=30+29)
XML 219ms ± 2% 217ms ± 2% ~ (p=0.091 n=29+24)

name old user-ns/op new user-ns/op delta
Template 272user-ms ± 3% 270user-ms ± 3% -1.03% (p=0.004 n=30+30)
Unicode 138user-ms ± 2% 138user-ms ± 3% ~ (p=0.902 n=29+29)
GoTypes 891user-ms ± 2% 883user-ms ± 2% -0.95% (p=0.000 n=29+29)
Compiler 3.85user-s ± 2% 3.84user-s ± 2% ~ (p=0.236 n=30+30)
Flate 167user-ms ± 2% 166user-ms ± 4% ~ (p=0.511 n=28+30)
GoParser 211user-ms ± 4% 210user-ms ± 3% ~ (p=0.287 n=29+30)
Reflect 539user-ms ± 3% 536user-ms ± 2% -0.59% (p=0.034 n=29+30)
Tar 154user-ms ± 3% 155user-ms ± 4% ~ (p=0.786 n=30+30)
XML 289user-ms ± 3% 288user-ms ± 4% ~ (p=0.249 n=30+26)

name old alloc/op new alloc/op delta
Template 40.7MB ± 0% 40.8MB ± 0% +0.09% (p=0.001 n=30+30)
Unicode 30.8MB ± 0% 30.8MB ± 0% ~ (p=0.112 n=30+30)
GoTypes 123MB ± 0% 124MB ± 0% +0.09% (p=0.000 n=30+30)
Compiler 473MB ± 0% 473MB ± 0% +0.05% (p=0.000 n=30+30)
Flate 26.5MB ± 0% 26.5MB ± 0% ~ (p=0.186 n=29+30)
GoParser 32.3MB ± 0% 32.4MB ± 0% +0.07% (p=0.021 n=28+30)
Reflect 84.4MB ± 0% 84.6MB ± 0% +0.21% (p=0.000 n=30+30)
Tar 27.3MB ± 0% 27.3MB ± 0% +0.09% (p=0.010 n=30+28)
XML 44.7MB ± 0% 44.7MB ± 0% +0.07% (p=0.002 n=30+30)

name old allocs/op new allocs/op delta
Template 401k ± 1% 400k ± 1% ~ (p=0.321 n=30+30)
Unicode 331k ± 1% 331k ± 1% ~ (p=0.357 n=30+28)
GoTypes 1.24M ± 0% 1.24M ± 1% -0.19% (p=0.001 n=30+30)
Compiler 4.27M ± 0% 4.27M ± 0% -0.13% (p=0.000 n=30+30)
Flate 252k ± 1% 251k ± 1% -0.30% (p=0.005 n=30+30)
GoParser 325k ± 1% 325k ± 1% ~ (p=0.224 n=28+30)
Reflect 1.06M ± 0% 1.05M ± 0% -0.34% (p=0.000 n=30+30)
Tar 266k ± 1% 266k ± 1% ~ (p=0.333 n=30+30)
XML 416k ± 1% 415k ± 1% ~ (p=0.144 n=30+29)

Change-Id: I6ba67a9203516373062a2618122306da73333d98
Reviewed-on: https://go-review.googlesource.com/36211
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>

b612ab3a

readme: add attribution for the Gopher image · ef259390

Chris Broadfoot authored Feb 02, 2017

Change-Id: I3b1317f0ab46e03d8c5a0af74c83183710a75055
Reviewed-on: https://go-review.googlesource.com/36214Reviewed-by: Russ Cox <rsc@golang.org>
Reviewed-by: Rob Pike <r@golang.org>

ef259390

time: record monotonic clock reading in time.Now, for more accurate comparisons · 0e335590

Russ Cox authored Feb 02, 2017

See https://golang.org/design/12914-monotonic for details.

Fixes #12914.

Change-Id: I80edc2e6c012b4ace7161c84cf067d444381a009
Reviewed-on: https://go-review.googlesource.com/36255
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Caleb Spare <cespare@gmail.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

0e335590

cmd/compile: make sure output params are live if there is a defer · 8179b9b4

Keith Randall authored Jan 30, 2017

If there is a defer, and that defer recovers, then the caller
can see all of the output parameters.  That means that we must
mark all the output parameters live at any point which might panic.

If there is no defer then this is not necessary.  This is implemented.

We could also detect whether there is a recover in any of the defers.
If not, we would need to mark only output params that the defer
actually references (and the closure mechanism already does that).
This is not implemented.

Fixes #18860.

Change-Id: If984fe6686eddce9408bf25e725dd17fc16b8578
Reviewed-on: https://go-review.googlesource.com/36030Reviewed-by: Austin Clements <austin@google.com>
Reviewed-by: Russ Cox <rsc@golang.org>

8179b9b4

cmd/compile: optimize (ZeroExt (Const [c])) · 12c58bbf

Josh Bleecher Snyder authored Feb 02, 2017

These rules trigger 116 times while running make.bash.
And at least for the sample code at
https://github.com/golang/go/issues/18906#issuecomment-277174241
they are providing optimizations not already present
in amd64.

Updates #18906

Change-Id: I410a480f566f5ab176fc573fb5ac74f9cffec225
Reviewed-on: https://go-review.googlesource.com/36217
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

12c58bbf

cmd/compile: speed up hot phi insertion code · 61fb2f6d

Josh Bleecher Snyder authored Jan 19, 2017

This speeds up compilation of the code in #8225 by 25%-30%.
The complexity of the algorithm is unchanged,
but this shrinks the constant factor so much that it doesn't matter,
even the size of the giant type switch gets scaled up dramatically.

name old time/op new time/op delta
Template 218ms ± 5% 217ms ±10% ~ (p=0.163 n=27+30)
Unicode 98.2ms ± 6% 97.7ms ±10% ~ (p=0.150 n=27+29)
GoTypes 654ms ± 5% 650ms ± 5% ~ (p=0.350 n=30+30)
Compiler 2.70s ± 4% 2.68s ± 3% ~ (p=0.128 n=30+29)

name old user-ns/op new user-ns/op delta
Template 276user-ms ± 6% 271user-ms ± 7% -1.83% (p=0.003 n=29+28)
Unicode 138user-ms ± 5% 137user-ms ± 4% ~ (p=0.071 n=27+27)
GoTypes 881user-ms ± 4% 877user-ms ± 4% ~ (p=0.423 n=30+30)
Compiler 3.76user-s ± 4% 3.72user-s ± 2% -0.84% (p=0.028 n=30+29)

name old alloc/op new alloc/op delta
Template 40.7MB ± 0% 40.7MB ± 0% ~ (p=0.936 n=30+30)
Unicode 30.8MB ± 0% 30.8MB ± 0% ~ (p=0.859 n=28+30)
GoTypes 123MB ± 0% 123MB ± 0% ~ (p=0.273 n=30+30)
Compiler 472MB ± 0% 472MB ± 0% ~ (p=0.432 n=30+30)

name old allocs/op new allocs/op delta
Template 401k ± 1% 401k ± 1% ~ (p=0.859 n=30+30)
Unicode 331k ± 0% 331k ± 1% ~ (p=0.823 n=28+30)
GoTypes 1.24M ± 0% 1.24M ± 0% ~ (p=0.286 n=30+30)
Compiler 4.26M ± 0% 4.26M ± 0% ~ (p=0.359 n=30+30)

Change-Id: Ia850065a9a84c07a5b0b4e23c1758b5679498da7
Reviewed-on: https://go-review.googlesource.com/36112
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>

61fb2f6d

runtime: darwin/amd64, don't depend on outarg slots being unmodified · 69e16349

Keith Randall authored Feb 02, 2017

sigtramp was calling sigtrampgo and depending on the fact that
the 3rd argument slot will not be modified on return.  Our calling
convention doesn't guarantee that.  Avoid that assumption.

There's no actual bug here, as sigtrampgo does not in fact modify its
argument slots.  But I found this while working on the dead stack slot
clobbering tool.  https://go-review.googlesource.com/c/23924/

Change-Id: Ia7e791a2b4c1c74fff24cba8169e7840b4b06ffc
Reviewed-on: https://go-review.googlesource.com/36216
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

69e16349

net/http: fix dns hijacking test · 64c52808

Russ Cox authored Feb 02, 2017

The name lookups are unrooted; the test should be unrooted too.
Correctly skips the tests if the DNS config specifies a domain
suffix that has a wildcard entry causing all unrooted names to resolve.

Change-Id: I80470326a5d332f3b8d64663f765fd304c5e0811
Reviewed-on: https://go-review.googlesource.com/36253
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

64c52808

02 Feb, 2017 26 commits

cmd/compile: add reusable []Location to ssa.Config · 57546d67

Josh Bleecher Snyder authored Jan 27, 2017

name old time/op new time/op delta
Template 218ms ± 3% 214ms ± 3% -1.70% (p=0.000 n=30+30)
Unicode 100ms ± 3% 100ms ± 4% ~ (p=0.614 n=29+30)
GoTypes 657ms ± 1% 660ms ± 3% +0.46% (p=0.046 n=29+30)
Compiler 2.80s ± 2% 2.80s ± 1% ~ (p=0.451 n=28+29)
Flate 131ms ± 2% 132ms ± 4% ~ (p=1.000 n=29+29)
GoParser 159ms ± 3% 160ms ± 5% ~ (p=0.341 n=28+30)
Reflect 406ms ± 3% 408ms ± 4% ~ (p=0.511 n=28+30)
Tar 118ms ± 4% 118ms ± 4% ~ (p=0.827 n=29+30)
XML 222ms ± 6% 222ms ± 3% ~ (p=0.532 n=30+30)

name old user-ns/op new user-ns/op delta
Template 274user-ms ± 3% 272user-ms ± 3% -0.87% (p=0.015 n=29+30)
Unicode 140user-ms ± 4% 140user-ms ± 3% ~ (p=0.735 n=29+30)
GoTypes 890user-ms ± 1% 897user-ms ± 2% +0.88% (p=0.002 n=29+30)
Compiler 3.88user-s ± 2% 3.89user-s ± 1% ~ (p=0.132 n=30+29)
Flate 168user-ms ± 2% 157user-ms ± 4% -6.21% (p=0.000 n=25+28)
GoParser 211user-ms ± 2% 213user-ms ± 5% ~ (p=0.086 n=28+30)
Reflect 539user-ms ± 2% 541user-ms ± 3% ~ (p=0.267 n=27+29)
Tar 156user-ms ± 7% 155user-ms ± 5% ~ (p=0.708 n=30+30)
XML 291user-ms ± 5% 294user-ms ± 3% +0.83% (p=0.029 n=29+30)

name old alloc/op new alloc/op delta
Template 40.7MB ± 0% 39.4MB ± 0% -3.26% (p=0.000 n=29+26)
Unicode 30.8MB ± 0% 30.7MB ± 0% -0.40% (p=0.000 n=28+30)
GoTypes 123MB ± 0% 119MB ± 0% -3.47% (p=0.000 n=30+29)
Compiler 472MB ± 0% 455MB ± 0% -3.60% (p=0.000 n=30+30)
Flate 26.5MB ± 0% 25.6MB ± 0% -3.21% (p=0.000 n=28+30)
GoParser 32.3MB ± 0% 31.4MB ± 0% -2.98% (p=0.000 n=29+30)
Reflect 84.4MB ± 0% 82.1MB ± 0% -2.83% (p=0.000 n=30+30)
Tar 27.3MB ± 0% 26.5MB ± 0% -2.70% (p=0.000 n=29+29)
XML 44.6MB ± 0% 43.1MB ± 0% -3.49% (p=0.000 n=30+30)

name old allocs/op new allocs/op delta
Template 401k ± 1% 399k ± 0% -0.35% (p=0.000 n=30+28)
Unicode 331k ± 0% 331k ± 1% ~ (p=0.907 n=28+30)
GoTypes 1.24M ± 0% 1.23M ± 0% -0.43% (p=0.000 n=30+30)
Compiler 4.26M ± 0% 4.25M ± 0% -0.34% (p=0.000 n=29+30)
Flate 252k ± 1% 251k ± 1% -0.41% (p=0.000 n=30+30)
GoParser 325k ± 1% 324k ± 1% -0.31% (p=0.000 n=27+30)
Reflect 1.06M ± 0% 1.05M ± 0% -0.69% (p=0.000 n=30+30)
Tar 266k ± 1% 265k ± 1% -0.51% (p=0.000 n=29+30)
XML 416k ± 1% 415k ± 1% -0.36% (p=0.002 n=30+30)

Change-Id: I8f784001324df83b2764c44f0e83a540e5beab34
Reviewed-on: https://go-review.googlesource.com/36212
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

57546d67

runtime: skip flaky TestGdbPythonCgo on MIPS · f69a6def

Cherry Zhang authored Feb 02, 2017

It seems the problem is on gdb and the dynamic linker. Skip the
test for now until we figure out what's going on with the system.

Updates #18784.

Change-Id: Ic9320ffd463f6c231b2c4192652263b1cf7f4231
Reviewed-on: https://go-review.googlesource.com/36250
Run-TryBot: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

f69a6def

doc: consistently link to the SettingGOPATH page · ecbf9084

Jaana Burcu Dogan authored Feb 02, 2017

Change-Id: I4fdd81aa7c9b180cb72ec4af3e7d9d803c99ecac
Reviewed-on: https://go-review.googlesource.com/36033Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

ecbf9084

cmd/compile: simplify IsNonNil ConstNil · 6ad2d6aa

Cherry Zhang authored Jan 20, 2017

Change-Id: I9ed5a2065cef06708e319b16c801da2eff42004e
Reviewed-on: https://go-review.googlesource.com/35497
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>

6ad2d6aa

cmd/compile: remove nil check for Zero/Move on 386, AMD64, S390X · fddc0045

Cherry Zhang authored Nov 21, 2016

Fixes #18003.

Change-Id: Iadcc5c424c64badecfb5fdbd4dbd9197df56182c
Reviewed-on: https://go-review.googlesource.com/33421
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>

fddc0045

cmd/compile: provide line number for cgo directive error (fix a TODO) · c1363b2d

Robert Griesemer authored Feb 01, 2017

Also: Remove double "go:" prefix in related error message.

Fixes #18882.

Change-Id: Ifbbd8e2f7529b43f035d3dbf7ca4a91f212bc6b6
Reviewed-on: https://go-review.googlesource.com/36121
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>

c1363b2d

runtime: use mach_absolute_time for runtime.nanotime · e546b295

Lars Wiegman authored Jan 17, 2017

The existing darwin/amd64 implementation of runtime.nanotime returns the
wallclock time, which results in timers not functioning properly when
system time runs backwards. By implementing the algorithm used by the
darwin syscall mach_absolute_time, timers will function as expected.

The algorithm is described at
https://opensource.apple.com/source/xnu/xnu-3248.60.10/libsyscall/wrappers/mach_absolute_time.s

Fixes #17610

Change-Id: I9c8d35240d48249a6837dca1111b1406e2686f67
Reviewed-on: https://go-review.googlesource.com/35292Reviewed-by: Russ Cox <rsc@golang.org>
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

e546b295

cmd/compile: skip convT2E for empty structs · 8958d8ce

Josh Bleecher Snyder authored Jan 22, 2017

Fixes #18402

Change-Id: I5af800857fb2e365ce4224eece9171277106ec7d
Reviewed-on: https://go-review.googlesource.com/35562
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>

8958d8ce

cmd/compile: better implementation of Slicemask · 3d5eb4a6

Keith Randall authored Jan 24, 2017

Use (-x)>>63 instead of ((x-1)>>63)^-1 to get a mask that
is 0 when x is 0 and all ones when x is positive.

Saves one instruction when slicing.

Change-Id: Ib46d53d3aac6530ac481fa2f265a6eadf3df0567
Reviewed-on: https://go-review.googlesource.com/35641
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>

3d5eb4a6

cmd/compile, runtime: convert byte-sized values to interfaces without allocation · 03583675

Josh Bleecher Snyder authored Jan 21, 2017

Based in part on khr's CL 2500.

Updates #17725
Updates #18121

Change-Id: I744e1f92fc2104e6c5bd883a898c30b2eea8cc31
Reviewed-on: https://go-review.googlesource.com/35555
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>

03583675

cmd/compile: convert constants to interfaces without allocating · c682d323

Josh Bleecher Snyder authored Jan 21, 2017

The order pass is responsible for ensuring that
values passed to runtime functions, including
convT2E/convT2I, are addressable.

Prior to this CL, this was always accomplished
by creating a temp, which frequently escaped to
the heap, causing allocations, perhaps most
notably in code like:

fmt.Println(1, 2, 3) // allocates three times

None of the runtime routines modify the contents
of the pointers they receive, so in the case of
constants, instead of creating a temp value,
we can create a static value.

(Marking the static value as read-only provides
protection against accidental attempts by the runtime
to modify the constant data.)

This improves code generation for code like:

panic("abc")
c <- 2 // c is a chan int

which can now simply refer to "abc" and 2,
rather than going by way of a temporary.

It also allows us to optimize convT2E/convT2I,
by recognizing static readonly values
and directly constructing the interface.

This CL adds ~0.5% to binary size, despite
decreasing the size of many functions,
because it also adds many static symbols.

This binary size regression could be recovered in
future (but currently unplanned) work.

There is a lot of content-duplication in these
symbols; this statement generates six new symbols,
three containing an int 1 and three containing
a pointer to the string "a":

fmt.Println(1, 1, 1, "a", "a", "a")

These symbols could be made content-addressable.

Furthermore, these symbols are small, so the
alignment and naming overhead is large.
As with the go.strings section, these symbols
could be hidden and have their alignment reduced.

The changes to test/live.go make it impossible
(at least with current optimization techniques)
to place the values being passed to the runtime
in static symbols, preserving autotmp creation.

Fixes #18704

Benchmarks from fmt and go-kit's logging package:

github.com/go-kit/kit/log

name old time/op new time/op delta
JSONLoggerSimple-8 1.91µs ± 2% 2.11µs ±22% ~ (p=1.000 n=9+10)
JSONLoggerContextual-8 2.60µs ± 6% 2.43µs ± 2% -6.29% (p=0.000 n=9+10)
Discard-8 101ns ± 2% 34ns ±14% -66.33% (p=0.000 n=10+9)
OneWith-8 161ns ± 1% 102ns ±16% -36.78% (p=0.000 n=10+10)
TwoWith-8 175ns ± 3% 106ns ± 7% -39.36% (p=0.000 n=10+9)
TenWith-8 293ns ± 3% 227ns ±15% -22.44% (p=0.000 n=9+10)
LogfmtLoggerSimple-8 704ns ± 2% 608ns ± 2% -13.65% (p=0.000 n=10+9)
LogfmtLoggerContextual-8 962ns ± 1% 860ns ±17% -10.57% (p=0.003 n=9+10)
NopLoggerSimple-8 188ns ± 1% 120ns ± 1% -36.39% (p=0.000 n=9+10)
NopLoggerContextual-8 379ns ± 1% 243ns ± 0% -35.77% (p=0.000 n=9+10)
ValueBindingTimestamp-8 577ns ± 1% 499ns ± 1% -13.51% (p=0.000 n=10+10)
ValueBindingCaller-8 898ns ± 2% 844ns ± 2% -6.00% (p=0.000 n=10+10)

name old alloc/op new alloc/op delta
JSONLoggerSimple-8 904B ± 0% 872B ± 0% -3.54% (p=0.000 n=10+10)
JSONLoggerContextual-8 1.20kB ± 0% 1.14kB ± 0% -5.33% (p=0.000 n=10+10)
Discard-8 64.0B ± 0% 32.0B ± 0% -50.00% (p=0.000 n=10+10)
OneWith-8 96.0B ± 0% 64.0B ± 0% -33.33% (p=0.000 n=10+10)
TwoWith-8 160B ± 0% 128B ± 0% -20.00% (p=0.000 n=10+10)
TenWith-8 672B ± 0% 640B ± 0% -4.76% (p=0.000 n=10+10)
LogfmtLoggerSimple-8 128B ± 0% 96B ± 0% -25.00% (p=0.000 n=10+10)
LogfmtLoggerContextual-8 304B ± 0% 240B ± 0% -21.05% (p=0.000 n=10+10)
NopLoggerSimple-8 128B ± 0% 96B ± 0% -25.00% (p=0.000 n=10+10)
NopLoggerContextual-8 304B ± 0% 240B ± 0% -21.05% (p=0.000 n=10+10)
ValueBindingTimestamp-8 159B ± 0% 127B ± 0% -20.13% (p=0.000 n=10+10)
ValueBindingCaller-8 112B ± 0% 80B ± 0% -28.57% (p=0.000 n=10+10)

name old allocs/op new allocs/op delta
JSONLoggerSimple-8 19.0 ± 0% 17.0 ± 0% -10.53% (p=0.000 n=10+10)
JSONLoggerContextual-8 25.0 ± 0% 21.0 ± 0% -16.00% (p=0.000 n=10+10)
Discard-8 3.00 ± 0% 1.00 ± 0% -66.67% (p=0.000 n=10+10)
OneWith-8 3.00 ± 0% 1.00 ± 0% -66.67% (p=0.000 n=10+10)
TwoWith-8 3.00 ± 0% 1.00 ± 0% -66.67% (p=0.000 n=10+10)
TenWith-8 3.00 ± 0% 1.00 ± 0% -66.67% (p=0.000 n=10+10)
LogfmtLoggerSimple-8 4.00 ± 0% 2.00 ± 0% -50.00% (p=0.000 n=10+10)
LogfmtLoggerContextual-8 7.00 ± 0% 3.00 ± 0% -57.14% (p=0.000 n=10+10)
NopLoggerSimple-8 4.00 ± 0% 2.00 ± 0% -50.00% (p=0.000 n=10+10)
NopLoggerContextual-8 7.00 ± 0% 3.00 ± 0% -57.14% (p=0.000 n=10+10)
ValueBindingTimestamp-8 5.00 ± 0% 3.00 ± 0% -40.00% (p=0.000 n=10+10)
ValueBindingCaller-8 4.00 ± 0% 2.00 ± 0% -50.00% (p=0.000 n=10+10)

fmt

name old time/op new time/op delta
SprintfPadding-8 88.9ns ± 3% 79.1ns ± 1% -11.09% (p=0.000 n=10+7)
SprintfEmpty-8 12.6ns ± 3% 12.8ns ± 3% ~ (p=0.136 n=10+10)
SprintfString-8 38.7ns ± 5% 26.9ns ± 6% -30.65% (p=0.000 n=10+10)
SprintfTruncateString-8 56.7ns ± 2% 47.0ns ± 3% -17.05% (p=0.000 n=10+10)
SprintfQuoteString-8 164ns ± 2% 153ns ± 2% -7.01% (p=0.000 n=10+10)
SprintfInt-8 38.9ns ±15% 26.5ns ± 2% -31.93% (p=0.000 n=10+9)
SprintfIntInt-8 60.3ns ± 9% 38.2ns ± 1% -36.67% (p=0.000 n=10+8)
SprintfPrefixedInt-8 58.6ns ±13% 51.2ns ±11% -12.66% (p=0.001 n=10+10)
SprintfFloat-8 71.4ns ± 3% 64.2ns ± 3% -10.08% (p=0.000 n=8+10)
SprintfComplex-8 175ns ± 3% 159ns ± 2% -9.03% (p=0.000 n=10+10)
SprintfBoolean-8 33.5ns ± 4% 25.7ns ± 5% -23.28% (p=0.000 n=10+10)
SprintfHexString-8 65.3ns ± 3% 51.7ns ± 5% -20.86% (p=0.000 n=10+9)
SprintfHexBytes-8 67.2ns ± 5% 67.9ns ± 4% ~ (p=0.383 n=10+10)
SprintfBytes-8 129ns ± 7% 124ns ± 7% ~ (p=0.074 n=9+10)
SprintfStringer-8 127ns ± 4% 126ns ± 8% ~ (p=0.506 n=9+10)
SprintfStructure-8 357ns ± 3% 359ns ± 3% ~ (p=0.469 n=10+10)
ManyArgs-8 203ns ± 6% 126ns ± 3% -37.94% (p=0.000 n=10+10)
FprintInt-8 119ns ±10% 74ns ± 3% -37.54% (p=0.000 n=10+10)
FprintfBytes-8 122ns ± 4% 120ns ± 3% ~ (p=0.124 n=10+10)
FprintIntNoAlloc-8 78.2ns ± 5% 74.1ns ± 3% -5.28% (p=0.000 n=10+10)
ScanInts-8 349µs ± 1% 349µs ± 0% ~ (p=0.606 n=9+8)
ScanRecursiveInt-8 43.8ms ± 7% 40.1ms ± 2% -8.42% (p=0.000 n=10+10)
ScanRecursiveIntReaderWrapper-8 43.5ms ± 4% 40.4ms ± 2% -7.16% (p=0.000 n=10+9)

name old alloc/op new alloc/op delta
SprintfPadding-8 24.0B ± 0% 16.0B ± 0% -33.33% (p=0.000 n=10+10)
SprintfEmpty-8 0.00B 0.00B ~ (all equal)
SprintfString-8 21.0B ± 0% 5.0B ± 0% -76.19% (p=0.000 n=10+10)
SprintfTruncateString-8 32.0B ± 0% 16.0B ± 0% -50.00% (p=0.000 n=10+10)
SprintfQuoteString-8 48.0B ± 0% 32.0B ± 0% -33.33% (p=0.000 n=10+10)
SprintfInt-8 16.0B ± 0% 1.0B ± 0% -93.75% (p=0.000 n=10+10)
SprintfIntInt-8 24.0B ± 0% 3.0B ± 0% -87.50% (p=0.000 n=10+10)
SprintfPrefixedInt-8 72.0B ± 0% 64.0B ± 0% -11.11% (p=0.000 n=10+10)
SprintfFloat-8 16.0B ± 0% 8.0B ± 0% -50.00% (p=0.000 n=10+10)
SprintfComplex-8 48.0B ± 0% 32.0B ± 0% -33.33% (p=0.000 n=10+10)
SprintfBoolean-8 8.00B ± 0% 4.00B ± 0% -50.00% (p=0.000 n=10+10)
SprintfHexString-8 96.0B ± 0% 80.0B ± 0% -16.67% (p=0.000 n=10+10)
SprintfHexBytes-8 112B ± 0% 112B ± 0% ~ (all equal)
SprintfBytes-8 96.0B ± 0% 96.0B ± 0% ~ (all equal)
SprintfStringer-8 32.0B ± 0% 32.0B ± 0% ~ (all equal)
SprintfStructure-8 256B ± 0% 256B ± 0% ~ (all equal)
ManyArgs-8 80.0B ± 0% 0.0B -100.00% (p=0.000 n=10+10)
FprintInt-8 8.00B ± 0% 0.00B -100.00% (p=0.000 n=10+10)
FprintfBytes-8 32.0B ± 0% 32.0B ± 0% ~ (all equal)
FprintIntNoAlloc-8 0.00B 0.00B ~ (all equal)
ScanInts-8 15.2kB ± 0% 15.2kB ± 0% ~ (p=0.248 n=9+10)
ScanRecursiveInt-8 21.6kB ± 0% 21.6kB ± 0% ~ (all equal)
ScanRecursiveIntReaderWrapper-8 21.7kB ± 0% 21.7kB ± 0% ~ (all equal)

name old allocs/op new allocs/op delta
SprintfPadding-8 2.00 ± 0% 1.00 ± 0% -50.00% (p=0.000 n=10+10)
SprintfEmpty-8 0.00 0.00 ~ (all equal)
SprintfString-8 2.00 ± 0% 1.00 ± 0% -50.00% (p=0.000 n=10+10)
SprintfTruncateString-8 2.00 ± 0% 1.00 ± 0% -50.00% (p=0.000 n=10+10)
SprintfQuoteString-8 2.00 ± 0% 1.00 ± 0% -50.00% (p=0.000 n=10+10)
SprintfInt-8 2.00 ± 0% 1.00 ± 0% -50.00% (p=0.000 n=10+10)
SprintfIntInt-8 3.00 ± 0% 1.00 ± 0% -66.67% (p=0.000 n=10+10)
SprintfPrefixedInt-8 2.00 ± 0% 1.00 ± 0% -50.00% (p=0.000 n=10+10)
SprintfFloat-8 2.00 ± 0% 1.00 ± 0% -50.00% (p=0.000 n=10+10)
SprintfComplex-8 2.00 ± 0% 1.00 ± 0% -50.00% (p=0.000 n=10+10)
SprintfBoolean-8 2.00 ± 0% 1.00 ± 0% -50.00% (p=0.000 n=10+10)
SprintfHexString-8 2.00 ± 0% 1.00 ± 0% -50.00% (p=0.000 n=10+10)
SprintfHexBytes-8 2.00 ± 0% 2.00 ± 0% ~ (all equal)
SprintfBytes-8 2.00 ± 0% 2.00 ± 0% ~ (all equal)
SprintfStringer-8 4.00 ± 0% 4.00 ± 0% ~ (all equal)
SprintfStructure-8 7.00 ± 0% 7.00 ± 0% ~ (all equal)
ManyArgs-8 8.00 ± 0% 0.00 -100.00% (p=0.000 n=10+10)
FprintInt-8 1.00 ± 0% 0.00 -100.00% (p=0.000 n=10+10)
FprintfBytes-8 1.00 ± 0% 1.00 ± 0% ~ (all equal)
FprintIntNoAlloc-8 0.00 0.00 ~ (all equal)
ScanInts-8 1.60k ± 0% 1.60k ± 0% ~ (all equal)
ScanRecursiveInt-8 1.71k ± 0% 1.71k ± 0% ~ (all equal)
ScanRecursiveIntReaderWrapper-8 1.71k ± 0% 1.71k ± 0% ~ (all equal)

Change-Id: I7ba72a25fea4140a0ba40a9f443103ed87cc69b5
Reviewed-on: https://go-review.googlesource.com/35554
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>

c682d323

io: fix test when MultiReader is inlined with -l=3 · f395e878

David Lazar authored Jan 27, 2017

This ensures there isn't a live reference to buf1 on our stack
when MultiReader is inlined.

Fixes #18819.

Change-Id: I96a8cdc1ffad8f8a10c0ddcbf0299005f3176b61
Reviewed-on: https://go-review.googlesource.com/35931
Run-TryBot: David Lazar <lazard@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
Reviewed-by: Russ Cox <rsc@golang.org>

f395e878

cmd/compile: reduce slice growth in fuseBlockPlain · 16e430e1

Josh Bleecher Snyder authored Jan 11, 2017

Instead of always appending to c.Values,
choose whichever slice is larger;
b.Values will be set to nil anyway.

Appending once instead of in a loop also
limits slice growth to once per function call
and is more efficient.

Reduces max rss for the program in #18602 by 6.5%,
and eliminates fuseBlockPlain from the alloc_space
pprof output. fuseBlockPlain previously accounted
for 16.74% of allocated memory.

Updates #18602.

Change-Id: I417b03722d011a59a679157da43dc91f4425210e
Reviewed-on: https://go-review.googlesource.com/35114
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Keith Randall <khr@golang.org>
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16e430e1

cmd/compile: move rotate instruction generation to SSA · 01c8719f

Keith Randall authored Dec 08, 2016

Remove rotate generation from walk.  Remove OLROT and ssa.Lrot* opcodes.
Generate rotates during SSA lowering for architectures that have them.

This CL will allow rotates to be generated in more situations,
like when the shift values are determined to be constant
only after some analysis.

Fixes #18254

Change-Id: I8d6d684ff5ce2511aceaddfda98b908007851079
Reviewed-on: https://go-review.googlesource.com/34232
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>

01c8719f

cmd/compile: allow inlining of functions with intrinsics in them · 8a9dc053

Keith Randall authored Dec 09, 2016

Intrinsics are ok to inline as they don't rewrite to actual calls.

Change-Id: Ieb19c834c61579823c62c6d1a1b425d6c4d4de23
Reviewed-on: https://go-review.googlesource.com/34272
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>

8a9dc053

cmd/compile: use len(s)<=cap(s) to remove more bounds checks · 73f92f9b

Keith Randall authored Nov 27, 2016

When we discover a relation x <= len(s), also discover the relation
x <= cap(s).  That way, in situations like:

a := s[x:]  // tests 0 <= x <= len(s)
b := s[:x]  // tests 0 <= x <= cap(s)

the second check can be eliminated.

Fixes #16813

Change-Id: Ifc037920b6955e43bac1a1eaf6bac63a89cfbd44
Reviewed-on: https://go-review.googlesource.com/33633
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Alexandru Moșoi <alexandru@mosoi.ro>
Reviewed-by: David Chase <drchase@google.com>

73f92f9b

cmd/compile: fix CSE with commutative ops · 6317f92f

Keith Randall authored Nov 27, 2016

CSE opportunities were being missed for commutative ops. We used to
order the args of commutative ops (by arg ID) once at the start of CSE.
But that may not be enough.

i1 = (Load ptr mem)
i2 = (Load ptr mem)
x1 = (Add i1 j)
x2 = (Add i2 j)

Equivalent commutative ops x1 and x2 may not get their args ordered in
the same way because because at the start of CSE, we don't know that
the i values will be CSEd. If x1 and x2 get opposite orders we won't
CSE them.

Instead, (re)order the args of commutative operations by their
equivalence class IDs each time we partition an equivalence class.

Change-Id: Ic609fa83b85299782a5e85bf93dc6023fccf4b0c
Reviewed-on: https://go-review.googlesource.com/33632
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Todd Neal <todd@tneal.org>

6317f92f

cmd/compile: improve error for wrong type in switch · 34b563f4

Emmanuel Odeke authored Jan 14, 2017

Fixes #10561.

Provides a better diagnostic message for failed type switch
satisfaction in the case that a value receiver is being used
in place of the pointer receiver that implements and satisfies
the interface.

Change-Id: If8c13ba13f2a8d81bf44bac7c3a66c12921ba921
Reviewed-on: https://go-review.googlesource.com/35235Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
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34b563f4

cmd/cgo: don't track same node twice in guessKinds · ba1a65fc

Hiroshi Ioka authored Feb 02, 2017

Change-Id: Ib2c1490a42e3485913a05a0b2fecdcc425d42871
Reviewed-on: https://go-review.googlesource.com/36083
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
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ba1a65fc

misc/cgo/testshared: remove unused flag.Parse() · 329fff0d

Daniel Martí authored Nov 26, 2016

TestMain doesn't make use of any flags.

Change-Id: I98ec582fb004045a5067618f605ccfeb1f9f4bbb
Reviewed-on: https://go-review.googlesource.com/33613Reviewed-by: David Crawshaw <crawshaw@golang.org>
Run-TryBot: David Crawshaw <crawshaw@golang.org>
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329fff0d

misc/ios: allow exit code 0 to mean test success · 312ea5bf

Elias Naur authored Feb 01, 2017

Tests that use TestMain might never call m.Run(), and simply return
from TestMain. In that case, the iOS test harness never sees the
PASS from the testing framework and assumes the test failed.

Allow an exit with exit code 0 to also mean test success, thereby
fixing the objdump test on iOS.

Change-Id: I1fe9077b05931aa0905e41b88945cd153c5b35b6
Reviewed-on: https://go-review.googlesource.com/36065Reviewed-by: David Crawshaw <crawshaw@golang.org>
Run-TryBot: Elias Naur <elias.naur@gmail.com>
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312ea5bf

cmd/compile: improve error message if init is directly invoked · cb6e0639

Emmanuel Odeke authored Jan 01, 2017

Fixes #8481.

Inform the user that init functions cannot be directly invoked
in user code, as mandated by the spec at:
http://golang.org/ref/spec#Program_initialization_and_execution.

Change-Id: Ib12c0c08718ffd48b76b6f9b13c76bb6612d2e7b
Reviewed-on: https://go-review.googlesource.com/34790Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
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cb6e0639

cmd/compile: intrinsify math.Sqrt by using only the ssa backend · dbd51ce9

Martin Möhrmann authored Nov 02, 2016

Change-Id: If3cb64f52fe0fd7331b6f1acf3d15dd705dfd633
Reviewed-on: https://go-review.googlesource.com/32591
Run-TryBot: Martin Möhrmann <moehrmann@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>

dbd51ce9

cmd/compile: fix conversion error message for printed slices · dba0d382

Emmanuel Odeke authored Jul 30, 2016

Fixes #15055.

Updates exprfmt printing using fmt verb "%v" to check that n.Left
is non-nil before attempting to print it, otherwise we'll print
the nodes in the list using verb "%.v".

Credit to @mdempsky for this approach and for finding
the root cause of the issue.

Change-Id: I20a6464e916dc70d5565e145164bb9553e5d3865
Reviewed-on: https://go-review.googlesource.com/25361Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
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dba0d382

test: add extra test for issue18661 · b443baba

Josh Bleecher Snyder authored Jan 21, 2017

Make sure that the lack of an lvalue doesn't
cause extra side-effects.

Updates #18661
Updates #18739

Change-Id: I52eb4b4a5c6f8ff5cddd2115455f853c18112c19
Reviewed-on: https://go-review.googlesource.com/36126
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
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b443baba

cmd/compile: skip reexporting types in reexportdep · edad59cf

Matthew Dempsky authored Feb 01, 2017

The binary export format embeds type definitions inline as necessary,
so there's no need to add them to exportlist. Also, constants are
embedded directly by value, so they can be omitted too.

Change-Id: Id1879eb97c298a5a52f615cf9883c346c7f7bd69
Reviewed-on: https://go-review.googlesource.com/36170
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
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Reviewed-by: Robert Griesemer <gri@golang.org>

edad59cf