Use AVX if available on 4th generation of Intel(TM) Core(TM) processors.

(collected on E5 2609v3 @1.9GHz)
name                        old speed      new speed       delta
Memmove/1-6                  158MB/s ± 0%    172MB/s ± 0%    +9.09% (p=0.000 n=16+16)
Memmove/2-6                  316MB/s ± 0%    345MB/s ± 0%    +9.09% (p=0.000 n=18+16)
Memmove/3-6                  517MB/s ± 0%    517MB/s ± 0%      ~ (p=0.445 n=16+16)
Memmove/4-6                  687MB/s ± 1%    690MB/s ± 0%    +0.35% (p=0.000 n=20+17)
Memmove/5-6                  729MB/s ± 0%    729MB/s ± 0%    +0.01% (p=0.000 n=16+18)
Memmove/6-6                  875MB/s ± 0%    875MB/s ± 0%    +0.01% (p=0.000 n=18+18)
Memmove/7-6                 1.02GB/s ± 0%   1.02GB/s ± 1%      ~ (p=0.139 n=19+20)
Memmove/8-6                 1.26GB/s ± 0%   1.26GB/s ± 0%    +0.00% (p=0.000 n=18+18)
Memmove/9-6                 1.42GB/s ± 0%   1.42GB/s ± 0%    +0.00% (p=0.000 n=17+18)
Memmove/10-6                1.58GB/s ± 0%   1.58GB/s ± 0%    +0.00% (p=0.000 n=19+19)
Memmove/11-6                1.74GB/s ± 0%   1.74GB/s ± 0%    +0.00% (p=0.001 n=18+17)
Memmove/12-6                1.90GB/s ± 0%   1.90GB/s ± 0%    +0.00% (p=0.000 n=19+19)
Memmove/13-6                2.05GB/s ± 0%   2.05GB/s ± 0%    +0.00% (p=0.000 n=18+19)
Memmove/14-6                2.21GB/s ± 0%   2.21GB/s ± 0%    +0.00% (p=0.000 n=16+20)
Memmove/15-6                2.37GB/s ± 0%   2.37GB/s ± 0%    +0.00% (p=0.004 n=19+20)
Memmove/16-6                2.53GB/s ± 0%   2.53GB/s ± 0%    +0.00% (p=0.000 n=16+16)
Memmove/32-6                4.67GB/s ± 0%   4.67GB/s ± 0%    +0.00% (p=0.000 n=17+17)
Memmove/64-6                8.67GB/s ± 0%   8.64GB/s ± 0%    -0.33% (p=0.000 n=18+17)
Memmove/128-6               12.6GB/s ± 0%   11.6GB/s ± 0%    -8.05% (p=0.000 n=16+19)
Memmove/256-6               16.3GB/s ± 0%   16.6GB/s ± 0%    +1.66% (p=0.000 n=20+18)
Memmove/512-6               21.5GB/s ± 0%   24.4GB/s ± 0%   +13.35% (p=0.000 n=18+17)
Memmove/1024-6              24.7GB/s ± 0%   33.7GB/s ± 0%   +36.12% (p=0.000 n=18+18)
Memmove/2048-6              27.3GB/s ± 0%   43.3GB/s ± 0%   +58.77% (p=0.000 n=19+17)
Memmove/4096-6              37.5GB/s ± 0%   50.5GB/s ± 0%   +34.56% (p=0.000 n=19+19)
MemmoveUnalignedDst/1-6      135MB/s ± 0%    146MB/s ± 0%    +7.69% (p=0.000 n=16+14)
MemmoveUnalignedDst/2-6      271MB/s ± 0%    292MB/s ± 0%    +7.69% (p=0.000 n=18+18)
MemmoveUnalignedDst/3-6      438MB/s ± 0%    438MB/s ± 0%      ~ (p=0.352 n=16+19)
MemmoveUnalignedDst/4-6      584MB/s ± 0%    584MB/s ± 0%      ~ (p=0.876 n=17+17)
MemmoveUnalignedDst/5-6      631MB/s ± 1%    632MB/s ± 0%    +0.25% (p=0.000 n=20+17)
MemmoveUnalignedDst/6-6      759MB/s ± 0%    759MB/s ± 0%    +0.00% (p=0.000 n=19+16)
MemmoveUnalignedDst/7-6      885MB/s ± 0%    883MB/s ± 1%      ~ (p=0.647 n=18+20)
MemmoveUnalignedDst/8-6     1.08GB/s ± 0%   1.08GB/s ± 0%    +0.00% (p=0.035 n=19+18)
MemmoveUnalignedDst/9-6     1.22GB/s ± 0%   1.22GB/s ± 0%      ~ (p=0.251 n=18+17)
MemmoveUnalignedDst/10-6    1.35GB/s ± 0%   1.35GB/s ± 0%      ~ (p=0.327 n=17+18)
MemmoveUnalignedDst/11-6    1.49GB/s ± 0%   1.49GB/s ± 0%      ~ (p=0.531 n=18+19)
MemmoveUnalignedDst/12-6    1.63GB/s ± 0%   1.63GB/s ± 0%      ~ (p=0.886 n=19+18)
MemmoveUnalignedDst/13-6    1.76GB/s ± 0%   1.76GB/s ± 1%    -0.24% (p=0.006 n=18+20)
MemmoveUnalignedDst/14-6    1.90GB/s ± 0%   1.90GB/s ± 0%      ~ (p=0.818 n=20+19)
MemmoveUnalignedDst/15-6    2.03GB/s ± 0%   2.03GB/s ± 0%      ~ (p=0.294 n=17+16)
MemmoveUnalignedDst/16-6    2.17GB/s ± 0%   2.17GB/s ± 0%      ~ (p=0.602 n=16+18)
MemmoveUnalignedDst/32-6    4.05GB/s ± 0%   4.05GB/s ± 0%    +0.00% (p=0.010 n=18+17)
MemmoveUnalignedDst/64-6    7.59GB/s ± 0%   7.59GB/s ± 0%    +0.00% (p=0.022 n=18+16)
MemmoveUnalignedDst/128-6   11.1GB/s ± 0%   11.4GB/s ± 0%    +2.79% (p=0.000 n=18+17)
MemmoveUnalignedDst/256-6   16.4GB/s ± 0%   16.7GB/s ± 0%    +1.59% (p=0.000 n=20+17)
MemmoveUnalignedDst/512-6   15.7GB/s ± 0%   21.3GB/s ± 0%   +35.87% (p=0.000 n=18+20)
MemmoveUnalignedDst/1024-6  16.0GB/s ±20%   31.5GB/s ± 0%   +96.93% (p=0.000 n=20+14)
MemmoveUnalignedDst/2048-6  19.6GB/s ± 0%   42.1GB/s ± 0%  +115.16% (p=0.000 n=17+18)
MemmoveUnalignedDst/4096-6  6.41GB/s ± 0%  33.18GB/s ± 0%  +417.56% (p=0.000 n=17+18)
MemmoveUnalignedSrc/1-6      171MB/s ± 0%    166MB/s ± 0%    -3.33% (p=0.000 n=19+16)
MemmoveUnalignedSrc/2-6      343MB/s ± 0%    342MB/s ± 1%    -0.41% (p=0.000 n=17+20)
MemmoveUnalignedSrc/3-6      508MB/s ± 0%    493MB/s ± 1%    -2.90% (p=0.000 n=17+17)
MemmoveUnalignedSrc/4-6      677MB/s ± 0%    660MB/s ± 2%    -2.55% (p=0.000 n=17+20)
MemmoveUnalignedSrc/5-6      790MB/s ± 0%    790MB/s ± 0%      ~ (p=0.139 n=17+17)
MemmoveUnalignedSrc/6-6      948MB/s ± 0%    946MB/s ± 1%      ~ (p=0.330 n=17+19)
MemmoveUnalignedSrc/7-6     1.11GB/s ± 0%   1.11GB/s ± 0%    -0.05% (p=0.026 n=17+17)
MemmoveUnalignedSrc/8-6     1.38GB/s ± 0%   1.38GB/s ± 0%      ~ (p=0.091 n=18+16)
MemmoveUnalignedSrc/9-6     1.42GB/s ± 0%   1.40GB/s ± 1%    -1.04% (p=0.000 n=19+20)
MemmoveUnalignedSrc/10-6    1.58GB/s ± 0%   1.56GB/s ± 1%    -1.15% (p=0.000 n=18+19)
MemmoveUnalignedSrc/11-6    1.73GB/s ± 0%   1.71GB/s ± 1%    -1.30% (p=0.000 n=20+20)
MemmoveUnalignedSrc/12-6    1.89GB/s ± 0%   1.87GB/s ± 1%    -1.18% (p=0.000 n=17+20)
MemmoveUnalignedSrc/13-6    2.05GB/s ± 0%   2.02GB/s ± 1%    -1.18% (p=0.000 n=17+20)
MemmoveUnalignedSrc/14-6    2.21GB/s ± 0%   2.18GB/s ± 1%    -1.14% (p=0.000 n=17+20)
MemmoveUnalignedSrc/15-6    2.36GB/s ± 0%   2.34GB/s ± 1%    -1.04% (p=0.000 n=17+20)
MemmoveUnalignedSrc/16-6    2.52GB/s ± 0%   2.49GB/s ± 1%    -1.26% (p=0.000 n=19+20)
MemmoveUnalignedSrc/32-6    4.82GB/s ± 0%   4.61GB/s ± 0%    -4.40% (p=0.000 n=19+20)
MemmoveUnalignedSrc/64-6    5.03GB/s ± 4%   7.97GB/s ± 0%   +58.55% (p=0.000 n=20+16)
MemmoveUnalignedSrc/128-6   11.1GB/s ± 0%   11.2GB/s ± 0%    +0.52% (p=0.000 n=17+18)
MemmoveUnalignedSrc/256-6   16.5GB/s ± 0%   16.4GB/s ± 0%    -0.10% (p=0.000 n=20+18)
MemmoveUnalignedSrc/512-6   21.0GB/s ± 0%   22.1GB/s ± 0%    +5.48% (p=0.000 n=14+17)
MemmoveUnalignedSrc/1024-6  24.9GB/s ± 0%   31.9GB/s ± 0%   +28.20% (p=0.000 n=19+20)
MemmoveUnalignedSrc/2048-6  23.3GB/s ± 0%   33.8GB/s ± 0%   +45.22% (p=0.000 n=17+19)
MemmoveUnalignedSrc/4096-6  37.3GB/s ± 0%   42.7GB/s ± 0%   +14.30% (p=0.000 n=17+17)

Change-Id: Iab488d93a293cdf573ab5cd89b95a818bbb5d531
Reviewed-on: https://go-review.googlesource.com/22515
Run-TryBot: Denis Nagorny <denis.nagorny@intel.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>

This partially reverts commit 4e24e1d9.
Since in release 1.7 VPSHUFD support negative constant as an argument,
removing it as part of 4e24e1d9 was wrong.
Add it back.

Change-Id: Id1a3e062fe8fb4cf538edb3f9970f0664f3f545f
Reviewed-on: https://go-review.googlesource.com/27712
Run-TryBot: Ilya Tocar <ilya.tocar@intel.com>
Reviewed-by: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Major reorganization of the crc32 code:

 - The arch-specific files now implement a well-defined interface
   (documented in crc32.go). They no longer have the responsibility of
   initializing and falling back to a non-accelerated implementation;
   instead, that happens in the higher level code.

 - The non-accelerated algorithms are moved to a separate file with no
   dependencies on other code.

 - The "cutoff" optimization for slicing-by-8 is moved inside the
   algorithm itself (as opposed to every callsite).

Tests are significantly improved:
 - direct tests for the non-accelerated algorithms.
 - "cross-check" tests for arch-specific implementations (all archs).
 - tests for misaligned buffers for both IEEE and Castagnoli.

Fixes #16909.

Change-Id: I9b6dd83b7a57cd615eae901c0a6d61c6b8091c74
Reviewed-on: https://go-review.googlesource.com/27935Reviewed-by: Keith Randall <khr@golang.org>

J0-4            71.9ns ± 1%  54.6ns ± 0%  -24.08%  (p=0.000 n=20+18)
J1-4            71.6ns ± 0%  55.4ns ± 0%  -22.60%  (p=0.000 n=19+20)
Jn-4             153ns ± 0%   118ns ± 1%  -22.71%  (p=0.000 n=20+20)
Y0-4            70.8ns ± 0%  53.9ns ± 0%  -23.87%  (p=0.000 n=19+19)
Y1-4            70.8ns ± 0%  54.1ns ± 0%  -23.54%  (p=0.000 n=20+20)
Yn-4             149ns ± 0%   116ns ± 0%  -22.15%  (p=0.000 n=19+20)

Fixes #16889

Change-Id: Ie88496407b42f6acb918ffae1226b1b4c0500cb9
Reviewed-on: https://go-review.googlesource.com/28086
Run-TryBot: Ilya Tocar <ilya.tocar@intel.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>

cmd/go links mingwex and mingw32 libraries to every package it builds.
This breaks when 2 different packages call same gcc standard library
function pow. gcc linker appends pow implementation to the compiled
package, and names that function "pow". But when these 2 compiled
packages are linked together into the final executable, linker
complains, because it finds two "pow" functions with the same name.

This CL stops linking of mingwex and mingw32 during package build -
that leaves pow function reference unresolved. pow reference gets
resolved as final executable is built, by having both internal and
external linker use mingwex and mingw32 libraries.

Fixes #8756

Change-Id: I50ddc79529ea5463c67118d668488345ecf069bc
Reviewed-on: https://go-review.googlesource.com/26670
Run-TryBot: Alex Brainman <alex.brainman@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

TestGetfsstat is failing on OS X 10.8.

Not sure why. Add more debug info.

Change-Id: I7dabb70dd7aeffda7e8959103db9e4886b84741e
Reviewed-on: https://go-review.googlesource.com/28220Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

The goal for these examples is to show how to mirror the
functionality of the sha256sum Unix utility, a common checksumming
tool, using the Go standard library.

Add a newline at the end of the input, so users will get the same
output if they type `echo 'hello world' | sha256sum`, since the
builtin shell echo appends a newline by default. Also use hex output
(instead of the shorter base64) since this is the default output
encoding for shasum/sha256sum.

Change-Id: I0036874b3cc5ba85432bfcb86f81b51c4e0238fd
Reviewed-on: https://go-review.googlesource.com/24868Reviewed-by: Emmanuel Odeke <emm.odeke@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Change-Id: I01bfab595c50582c5adf958dcecbd58524dbc28f
Reviewed-on: https://go-review.googlesource.com/28212
Run-TryBot: Dave Cheney <dave@cheney.net>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

In the event of an unexpected error, we should always flush available
decompressed data to the user.

Fixes #16924

Change-Id: I0bc0824c3201f3149e84e6a26e3dbcba72a1aae5
Reviewed-on: https://go-review.googlesource.com/28216
Run-TryBot: Joe Tsai <thebrokentoaster@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>

Change-Id: I0a3726f841122643bd1680ef6bd450c2039f362b
Reviewed-on: https://go-review.googlesource.com/28213Reviewed-by: Rob Pike <r@golang.org>

As @pmarks-net said in the bug, this is something of a prisoner's
dilemma, but it does help people who occasionally report problems.

This is temporary. IPv6 is happening regardless of our decision here,
so we'll do this for now.

Fixes #15324

Change-Id: I8cc29c6efa56222970996c71182fc9ee89d78539
Reviewed-on: https://go-review.googlesource.com/28077
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Andrew Gerrand <adg@golang.org>

Fix bug in UnknownAuthorityError.Error that would never allow Org
Name to be inserted into error message if the Common Name was empty.
Create tests for all three paths in UnknownAuthorityError.Error

Change-Id: Id8afc444e897ef549df682d93a8563fd9de22a2b
Reviewed-on: https://go-review.googlesource.com/27992
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Change-Id: I37706ff0a3486827c5b072c95ad890ea87ede847
Reviewed-on: https://go-review.googlesource.com/28210
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

On ARM64, MIPS64, and PPC64, some floating point registers were
reserved for constants 0, 1, 2, 0.5, etc. This CL removes them.

On ARM64, they are never used. On MIPS64 and PPC64, the only use
case is a multiplication-by-2 in the old backend of the compiler,
which is replaced with an addition.

Change-Id: I737cbf43283756e3408964fc88c567a938c57036
Reviewed-on: https://go-review.googlesource.com/28095
Run-TryBot: Cherry Zhang <cherryyz@google.com>
Reviewed-by: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Recognize runtime.newobject and don't Zero or NilCheck it.

Fixes #15914 (?)
Updates #15390.

TBD: add test

Change-Id: Ia3bfa5c2ddbe2c27c92d9f68534a713b5ce95934
Reviewed-on: https://go-review.googlesource.com/27930
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>

This change makes sure that tests are run with the correct
version of the go tool.  The correct version is the one that
we invoked with "go test", not the one that is first in our path.

Fixes #16577

Change-Id: If22c8f8c3ec9e7c35d094362873819f2fbb8559b
Reviewed-on: https://go-review.googlesource.com/28089Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Use terms like "equal" and "identical types" to match the Go spec,
rather than inventing a new explanation. See also discussion on
golang.org/cl/27170.

Updates #16348.

Change-Id: I0fe0bd01c0d1da3c8937a579c2ba44cf1eb16b71
Reviewed-on: https://go-review.googlesource.com/28054Reviewed-by: Rob Pike <r@golang.org>

Change-Id: I2d01f692ae30a166079976b86bf0b7a439f05d5c
Reviewed-on: https://go-review.googlesource.com/28178
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Fixes C compiler warning:

./main.go:54:1: warning: control reaches end of non-void function [-Wreturn-type]

Should help fix the linux builders
that broke due to CL 23005.

Change-Id: Ib0630798125e35a12f99d666b7ffe7b3196f0ecc
Reviewed-on: https://go-review.googlesource.com/28176
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

It's only needed for a check that can be pushed up into bimport.go,
where it makes more sense anyway.

Change-Id: I6ef381ff4f29627b0f390ce27fef08902932bea6
Reviewed-on: https://go-review.googlesource.com/28177
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Change-Id: Icb1671187d70edd962e2bda2cc45771b17a8e770
Reviewed-on: https://go-review.googlesource.com/28175
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Change-Id: Idd3e677dec00eb36a2cf7baa34e772335e1f2bc8
Reviewed-on: https://go-review.googlesource.com/28173
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Consider a switch statement like:

switch x {
case 1:
  // ...
case 2, 3, 4, 5, 6:
  // ...
case 5:
  // ...
}

Prior to this CL, the generated code treated
2, 3, 4, 5, and 6 independently in a binary search.
With this CL, the generated code checks whether
2 <= x && x <= 6.
walkinrange then optimizes that range check
into a single unsigned comparison.

Experiments suggest that the best min range size
is 2, using binary size as a proxy for optimization.

Binary sizes before/after this CL:

cmd/compile: 14209728 / 14165360
cmd/go:       9543100 /  9539004

Change-Id: If2f7fb97ca80468fa70351ef540866200c4c996c
Reviewed-on: https://go-review.googlesource.com/26770
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>

This is a follow-up to the discussion
in CL 27853.

During make.bash, trigger count:

24 rewrite generic.rules:57
22 rewrite generic.rules:69
10 rewrite generic.rules:54
10 rewrite generic.rules:58
10 rewrite generic.rules:67
 7 rewrite generic.rules:66
 4 rewrite generic.rules:59
 3 rewrite generic.rules:50
 3 rewrite generic.rules:51
 3 rewrite generic.rules:52
 1 rewrite generic.rules:64

Change-Id: Id96cb6a707a4a564831f763c2d4d0e180c94bbef
Reviewed-on: https://go-review.googlesource.com/28088
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Martin Möhrmann <martisch@uos.de>

These were a hack abstraction for before FuncType existed.

The result value from calling FuncType() could be saved, but this
maintains the current idiom of consistently using t.FuncType().foo
everywhere in case we choose to evolve the API further.

Change-Id: I81f19aaeab6fb7caa2d4da8bf0bbbc358ab970d0
Reviewed-on: https://go-review.googlesource.com/28150
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>

Current code assumes there are not ".." in the Clean(path).
That's not true. Clean doesn't handle leading "..", so we need to stop
normalization if we see "..".

Fixes #16793

Change-Id: I0a7901bedac17f1210b134d593ebd9f5e8483775
Reviewed-on: https://go-review.googlesource.com/27410Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Alex Brainman <alex.brainman@gmail.com>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Change-Id: I6c48683b620b0f119d7f0ae4a88502773202756b
Reviewed-on: https://go-review.googlesource.com/28170Reviewed-by: Matthew Dempsky <mdempsky@google.com>

Change-Id: Iff2b1507dce08ef7c27085c8e0f45d0e3e88c476
Reviewed-on: https://go-review.googlesource.com/28152
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

For #15323.

Change-Id: I23192a05ce57012aa2f96909d90d6a33b913766b
Reviewed-on: https://go-review.googlesource.com/28151
Run-TryBot: Robert Griesemer <gri@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>

Ordering fix: this CL swaps the order of the log write and the channel close
in WroteRequest. I could reproduce the bug by putting a sleep between the two
when the channel close was first. It needs to happen after the log.

Data race: use the log buffer's mutex when reading too. Not really
important once the ordering fix above is fixed (since nobody is
concurrently writing anymore), but for consistency.

Fixes #16414

Change-Id: If6657884e67be90b4455c8f5a6f7bc6981999ee4
Reviewed-on: https://go-review.googlesource.com/28078
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

Generate a for loop for ranging over strings that only needs to call
the runtime function charntorune for non ASCII characters.

This provides faster iteration over ASCII characters and slightly
faster iteration for other characters.

The runtime function charntorune is changed to take an index from where
to start decoding and returns the index after the last byte belonging
to the decoded rune.

All call sites of charntorune in the runtime are replaced by a for loop
that will be transformed by the compiler instead of calling the charntorune
function directly.

go binary size decreases by 80 bytes.
godoc binary size increases by around 4 kilobytes.

runtime:

name                           old time/op  new time/op  delta
RuneIterate/range/ASCII-4      43.7ns ± 3%  10.3ns ± 4%  -76.33%  (p=0.000 n=44+45)
RuneIterate/range/Japanese-4   72.5ns ± 2%  62.8ns ± 2%  -13.41%  (p=0.000 n=49+50)
RuneIterate/range1/ASCII-4     43.5ns ± 2%  10.4ns ± 3%  -76.18%  (p=0.000 n=50+50)
RuneIterate/range1/Japanese-4  72.5ns ± 2%  62.9ns ± 2%  -13.26%  (p=0.000 n=50+49)
RuneIterate/range2/ASCII-4     43.5ns ± 3%  10.3ns ± 2%  -76.22%  (p=0.000 n=48+47)
RuneIterate/range2/Japanese-4  72.4ns ± 2%  62.7ns ± 2%  -13.47%  (p=0.000 n=50+50)

strings:

name                 old time/op    new time/op    delta
IndexRune-4            64.7ns ± 5%    22.4ns ± 3%  -65.43%  (p=0.000 n=25+21)
MapNoChanges-4          269ns ± 2%     157ns ± 2%  -41.46%  (p=0.000 n=23+24)
Fields-4               23.0ms ± 2%    19.7ms ± 2%  -14.35%  (p=0.000 n=25+25)
FieldsFunc-4           23.1ms ± 2%    19.6ms ± 2%  -14.94%  (p=0.000 n=25+24)

name                 old speed      new speed      delta
Fields-4             45.6MB/s ± 2%  53.2MB/s ± 2%  +16.87%  (p=0.000 n=24+25)
FieldsFunc-4         45.5MB/s ± 2%  53.5MB/s ± 2%  +17.57%  (p=0.000 n=25+24)

Updates #13162

Change-Id: I79ffaf828d82bf9887592f08e5cad883e9f39701
Reviewed-on: https://go-review.googlesource.com/27853
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
Run-TryBot: Martin Möhrmann <martisch@uos.de>

noescape is now 0 instructions with the SSA backend.
fast atomics are no longer a TODO (at least for amd64).

Change-Id: Ib6e06f7471bef282a47ba236d8ce95404bb60a42
Reviewed-on: https://go-review.googlesource.com/28087
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Internal objects that satisfy the Printable interface can print
directly to a printer w/o going through the conversion to a string
first.

Made printer.f understand and special-case %v so that Printable
objects use the printer directly.

This is work in progress and we may end up doing something else
eventually (perhaps using fmt.Formatter) - or even undo these
changes if this exploration doesn't get us to a significantly
better place.

Allocations numbers relative to commit c85b77c2 (still up, but
reduced from most recent change):

name       old time/op     new time/op     delta
Template       307ms ± 4%      315ms ± 4%   +2.55%        (p=0.000 n=29+29)
Unicode        164ms ± 4%      165ms ± 4%     ~           (p=0.057 n=30+30)
GoTypes        1.01s ± 3%      1.03s ± 3%   +1.72%        (p=0.000 n=30+30)
Compiler       5.49s ± 1%      5.62s ± 2%   +2.31%        (p=0.000 n=30+28)

name       old user-ns/op  new user-ns/op  delta
Template        397M ± 3%       406M ± 6%   +2.21%        (p=0.000 n=28+30)
Unicode         225M ± 4%       226M ± 3%     ~           (p=0.230 n=29+30)
GoTypes        1.31G ± 3%      1.34G ± 5%   +2.79%        (p=0.000 n=30+30)
Compiler       7.39G ± 2%      7.50G ± 2%   +1.43%        (p=0.000 n=30+29)

name       old alloc/op    new alloc/op    delta
Template      46.8MB ± 0%     47.5MB ± 0%   +1.48%        (p=0.000 n=29+28)
Unicode       37.8MB ± 0%     38.1MB ± 0%   +0.64%        (p=0.000 n=30+28)
GoTypes        143MB ± 0%      145MB ± 0%   +1.72%        (p=0.000 n=30+30)
Compiler       683MB ± 0%      706MB ± 0%   +3.31%        (p=0.000 n=30+29)

name       old allocs/op   new allocs/op   delta
Template        444k ± 0%       481k ± 0%   +8.38%        (p=0.000 n=30+30)
Unicode         369k ± 0%       379k ± 0%   +2.74%        (p=0.000 n=30+30)
GoTypes        1.35M ± 0%      1.50M ± 0%  +10.78%        (p=0.000 n=30+30)
Compiler       5.66M ± 0%      6.25M ± 0%  +10.31%        (p=0.000 n=29+29)

For #16897.

Change-Id: I37f95ab60508018ee6d29a98d238482b60e3e4b5
Reviewed-on: https://go-review.googlesource.com/28072Reviewed-by: Matthew Dempsky <mdempsky@google.com>

I was confused by the current wording. This wording
answers the question more clearly.

Thanks to Robert Griesemer for suggestions.

Fixes #16916

Change-Id: I50187c8df2db661b9581f4b3c5d5c279d2f9af41
Reviewed-on: https://go-review.googlesource.com/28052Reviewed-by: Robert Griesemer <gri@golang.org>

Uses the same implementation as runtime/internal/atomic.

Reorganize the intrinsic detector to make it more table-driven.

Also works on amd64p32.

Change-Id: I7a5238951d6018d7d5d1bc01f339f6ee9282b2d0
Reviewed-on: https://go-review.googlesource.com/28076Reviewed-by: Cherry Zhang <cherryyz@google.com>

Avoid new'ing memory that will be overwritten by assignment.

name              old time/op    new time/op    delta
Call-4               160ns ± 4%     155ns ± 2%  -3.19%        (p=0.003 n=10+10)
FieldByName1-4      94.5ns ± 2%    95.2ns ± 1%  +0.65%          (p=0.026 n=9+9)
FieldByName2-4      3.09µs ± 4%    3.13µs ± 2%    ~           (p=0.165 n=10+10)
FieldByName3-4      19.8µs ± 1%    19.9µs ± 1%    ~            (p=0.395 n=10+8)
InterfaceBig-4      11.6ns ± 0%    11.7ns ± 0%  +0.86%          (p=0.000 n=8+9)
InterfaceSmall-4    11.7ns ± 0%    11.7ns ± 0%    ~     (all samples are equal)
New-4               26.6ns ± 0%    26.4ns ± 0%  -0.64%         (p=0.000 n=10+9)

name              old alloc/op   new alloc/op   delta
Call-4              0.00B ±NaN%    0.00B ±NaN%    ~     (all samples are equal)

name              old allocs/op  new allocs/op  delta
Call-4               0.00 ±NaN%     0.00 ±NaN%    ~     (all samples are equal)

Change-Id: I12c85d4e65245598669dd6f66beb0744ec9b9d6d
Reviewed-on: https://go-review.googlesource.com/28011
Run-TryBot: Dave Cheney <dave@cheney.net>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Fixes #14698

Change-Id: I82fa781bf136c30e900d8e910ff576ba8b218acb
Reviewed-on: https://go-review.googlesource.com/23005
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

Change-Id: I84faeae69f294b9a70e545faac6a070feba67770
Reviewed-on: https://go-review.googlesource.com/28074
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Andrew Gerrand <adg@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>

Change-Id: I8434925661dc11396380af65c192c9f0dc191287
Reviewed-on: https://go-review.googlesource.com/27973Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Updates #14595

Change-Id: Idf60b3004c7a0ebb59dd48389ab62c854069e09f
Reviewed-on: https://go-review.googlesource.com/28073
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Andrew Gerrand <adg@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>