These used to be necessary when racing with updates to the mark bit,
but since the mark bit is no longer in the bitmap and the checkmark is
only updated with the world stopped, we can now always use regular
writes to update the type information in the heap bitmap.

Somewhat surprisingly, this has basically no overall performance
effect beyond the usual noise, but it does clean up the code.

Change-Id: I3933d0b4c0bc1c9bcf6313613515c0b496212105
Reviewed-on: https://go-review.googlesource.com/29277
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Rick Hudson <rlh@golang.org>

Change-Id: I808fab97076493a95b0b5eb0ad15645099f54aee
Reviewed-on: https://go-review.googlesource.com/29492Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

This change fixes the broken build caused by CL 23780.

Change-Id: I142cf8a1af033d036d57ac56e9e21ea925d922d4
Reviewed-on: https://go-review.googlesource.com/29490
Run-TryBot: Mikio Hara <mikioh.mikioh@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Change-Id: I6634f70d6bd1a4eced47eda69a2d9b207d222a1b
Reviewed-on: https://go-review.googlesource.com/29470
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>

Change-Id: Idcb5a8d6676aa38b4ebd0975edd2068386f5ca83
Reviewed-on: https://go-review.googlesource.com/29449
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

It is possible (and common) for Windows systems to use a different codepage
for console applications from that used on normal windowed application
(called ANSI codepage); for instance, most of the western Europe uses
CP850 for console (for backward compatibility with MS-DOS), while
windowed applications use a different codepage depending on the country
(eg: CP1252 aka Latin-1). The usage being changed with this commit is
specifically related to decoding input coming from the console, so the
previous usage of the ANSI codepage was wrong.

Also fixes an issue that previous did convert bytes as NFD. Go is
designed to handle single Unicode code point. This fix change behaivor
to NFC.

Fixes #16857.

Change-Id: I4f41ae83ece47321b6e9a79a2087ecbb8ac066dd
Reviewed-on: https://go-review.googlesource.com/27575Reviewed-by: Hiroshi Ioka <hirochachacha@gmail.com>
Reviewed-by: Alex Brainman <alex.brainman@gmail.com>

Updates #16360

Change-Id: I80b981aa291a8e16d2986d4a2dfd84d3819bf488
Reviewed-on: https://go-review.googlesource.com/29443
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Joe Tsai <thebrokentoaster@gmail.com>

Fixes #17170

Change-Id: I939f087df133710495fdf6f09040051cb9b176d7
Reviewed-on: https://go-review.googlesource.com/29442Reviewed-by: Ian Lance Taylor <iant@golang.org>

Move a value to the block which is the lowest common ancestor in the
dominator tree of all of its uses.  Make sure not to move a value into a
loop.

Makes the tighten pass on average (across go1 benchmarks) 40% slower.
Still not a big contributor to overall compile time.

Binary size is just a tad smaller.

name                      old time/op    new time/op    delta
BinaryTree17-12              2.77s ± 9%     2.76s ± 9%     ~     (p=0.878 n=8+8)
Fannkuch11-12                2.75s ± 1%     2.74s ± 1%     ~     (p=0.232 n=8+7)
FmtFprintfEmpty-12          48.9ns ± 9%    47.7ns ± 0%     ~     (p=0.431 n=8+8)
FmtFprintfString-12          143ns ± 8%     142ns ± 1%     ~     (p=0.257 n=8+7)
FmtFprintfInt-12             123ns ± 1%     122ns ± 1%   -1.04%  (p=0.026 n=7+8)
FmtFprintfIntInt-12          195ns ± 7%     185ns ± 0%   -5.32%  (p=0.000 n=8+8)
FmtFprintfPrefixedInt-12     194ns ± 4%     195ns ± 0%   +0.81%  (p=0.015 n=7+7)
FmtFprintfFloat-12           267ns ± 0%     268ns ± 0%   +0.37%  (p=0.001 n=7+6)
FmtManyArgs-12               800ns ± 0%     762ns ± 1%   -4.78%  (p=0.000 n=8+8)
GobDecode-12                7.67ms ± 2%    7.60ms ± 2%     ~     (p=0.234 n=8+8)
GobEncode-12                6.55ms ± 0%    6.57ms ± 1%     ~     (p=0.336 n=7+8)
Gzip-12                      237ms ± 0%     238ms ± 0%   +0.40%  (p=0.017 n=7+7)
Gunzip-12                   40.8ms ± 0%    40.2ms ± 0%   -1.52%  (p=0.000 n=7+8)
HTTPClientServer-12          208µs ± 3%     209µs ± 3%     ~     (p=0.955 n=8+7)
JSONEncode-12               16.2ms ± 1%    17.2ms ±11%   +5.80%  (p=0.001 n=7+8)
JSONDecode-12               57.3ms ±12%    55.5ms ± 3%     ~     (p=0.867 n=8+7)
Mandelbrot200-12            4.68ms ± 6%    4.46ms ± 1%     ~     (p=0.442 n=8+8)
GoParse-12                  4.27ms ±44%    3.42ms ± 1%  -19.95%  (p=0.005 n=8+8)
RegexpMatchEasy0_32-12      75.1ns ± 0%    75.8ns ± 1%   +0.99%  (p=0.002 n=7+7)
RegexpMatchEasy0_1K-12       963ns ± 0%    1021ns ± 6%   +5.98%  (p=0.001 n=7+7)
RegexpMatchEasy1_32-12      72.4ns ±11%    70.8ns ± 1%     ~     (p=0.368 n=8+8)
RegexpMatchEasy1_1K-12       394ns ± 1%     399ns ± 0%   +1.23%  (p=0.000 n=8+7)
RegexpMatchMedium_32-12      114ns ± 0%     115ns ± 1%   +0.63%  (p=0.021 n=7+7)
RegexpMatchMedium_1K-12     35.9µs ± 0%    37.6µs ± 1%   +4.72%  (p=0.000 n=7+8)
RegexpMatchHard_32-12       1.93µs ± 2%    1.91µs ± 0%   -0.91%  (p=0.001 n=7+7)
RegexpMatchHard_1K-12       60.2µs ± 3%    61.2µs ±10%     ~     (p=0.442 n=8+8)
Revcomp-12                   404ms ± 1%     406ms ± 1%     ~     (p=0.054 n=8+7)
Template-12                 64.6ms ± 1%    63.5ms ± 1%   -1.66%  (p=0.000 n=8+8)
TimeParse-12                 347ns ± 8%     309ns ± 0%  -11.13%  (p=0.000 n=8+7)
TimeFormat-12                343ns ± 4%     331ns ± 0%   -3.34%  (p=0.000 n=8+7)

Change-Id: Id6da1239ddd4d0cb074ff29cffb06302d1c6d08f
Reviewed-on: https://go-review.googlesource.com/28712
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>

Change-Id: If2cf3c5a29afc6cf74c3b08b9745e950231ead37
Reviewed-on: https://go-review.googlesource.com/29441Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Don't panic, crash, or return references to uninitialized memory when
ParseDirent is passed invalid input.

Move common dirent parsing to syscall.go with minimal platform-specific
functions in syscall_$GOOS.go.

Fixes #15653

Change-Id: I5602475e02321fe381064488401c14b33bec6886
Reviewed-on: https://go-review.googlesource.com/23780
Run-TryBot: Damien Neil <dneil@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Issue #17099 shows a failure that indicates we rescanned a stack twice
concurrently during mark termination, which suggests that the rescan
list became inconsistent. Add a simple check when we dequeue something
from the rescan list that it claims to be at the index where we found
it.

Change-Id: I6a267da4154a2e7b7d430cb4056e6bae978eaf62
Reviewed-on: https://go-review.googlesource.com/29280
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Rick Hudson <rlh@golang.org>

The comment block at the end of the heap profile includes *almost*
everything from MemStats. Add the missing fields. These are useful for
debugging RSS that has gone to GC-internal data structures.

Change-Id: I0ee8a918d49629e28fd8fd2bf6861c4529461c24
Reviewed-on: https://go-review.googlesource.com/29276
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Rick Hudson <rlh@golang.org>

On ARM, DIV, DIVU, MOD, MODU are pseudo instructions that makes
runtime calls _div/_udiv/_mod/_umod, which themselves are wrappers
of udiv. The udiv function does the real thing.

Instead of generating these pseudo instructions, call to udiv
directly. This removes one layer of wrappers (which has an awkward
way of passing argument), and also allows combining DIV and MOD
if both results are needed.

Change-Id: I118afc3986db3a1daabb5c1e6e57430888c91817
Reviewed-on: https://go-review.googlesource.com/29390Reviewed-by: David Chase <drchase@google.com>

Tracing happens at the http.Trace level. Fix the example to demostrate
tracing in the lifecycle of a RoundTrip.

Updates #17152.

Change-Id: Ic7d7bcc550176189206185482e8962dbf1504ff1
Reviewed-on: https://go-review.googlesource.com/29431Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

This time in elf.go.

Change-Id: Ifaf71742ebbc9aadc8606c39ea2d417ae5cc7e0d
Reviewed-on: https://go-review.googlesource.com/29450
Run-TryBot: Michael Hudson-Doyle <michael.hudson@canonical.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

Change-Id: Iee8f773355870f2333637a093e51c5fd36e5a6e5
Reviewed-on: https://go-review.googlesource.com/29349
Run-TryBot: Michael Hudson-Doyle <michael.hudson@canonical.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

Specifically Addstring, Addbytes and Symgrow.

Change-Id: Ia74093bfcf9f360bf223accbc8feef54a7f059c9
Reviewed-on: https://go-review.googlesource.com/29348
Run-TryBot: Michael Hudson-Doyle <michael.hudson@canonical.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

Change-Id: I25d9f74cb52e6fd4f2ad4b1c8b7102efadbc7481
Reviewed-on: https://go-review.googlesource.com/29344
Run-TryBot: Michael Hudson-Doyle <michael.hudson@canonical.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

Done with two eg templates:

package p

import (
	"cmd/link/internal/ld"
)

func before(ctxt *ld.Link, name string, v int) *ld.Symbol {
	return ld.Linklookup(ctxt, name, v)
}
func after(ctxt *ld.Link, name string, v int) *ld.Symbol {
	return ctxt.Syms.Lookup(name, v)
}

package p

import (
	"cmd/link/internal/ld"
)

func before(ctxt *ld.Link, name string, v int) *ld.Symbol {
	return ld.Linkrlookup(ctxt, name, v)
}
func after(ctxt *ld.Link, name string, v int) *ld.Symbol {
	return ctxt.Syms.ROLookup(name, v)
}

Change-Id: I00647dbf62294557bd24c29ad1f108fc786335f1
Reviewed-on: https://go-review.googlesource.com/29343
Run-TryBot: Michael Hudson-Doyle <michael.hudson@canonical.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

Mostly done with sed.

Change-Id: Ic8c534a3fdd332b5420d062ee85bb77a30ad1efb
Reviewed-on: https://go-review.googlesource.com/29346
Run-TryBot: Michael Hudson-Doyle <michael.hudson@canonical.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

Mechanical refactorings to follow.

Change-Id: I9b98e69a58c3cba7c7d1d3e3f600d4ed99d4fce2
Reviewed-on: https://go-review.googlesource.com/29342
Run-TryBot: Michael Hudson-Doyle <michael.hudson@canonical.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

This makes it possible for cmd/compile, when run with -dynlink on
darwin/amd64, to generate TLS_LE relocations which the linker then
turns into the appropriate PC-relative GOT load.

Change-Id: I1a71da432608bdb108ff66c22de600100209c873
Reviewed-on: https://go-review.googlesource.com/29393Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Change-Id: I58253a6cd2d77a9319c0783afb0d92cd5a88a7f7
Reviewed-on: https://go-review.googlesource.com/29370
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Michael Hudson-Doyle <michael.hudson@canonical.com>

Instead of using ctxt.Cursym, Errorf takes an explicit *Symbol
parameter. This removes most uses of Cursym and means the *Link
context object is needed in fewer parts of the linker.

All transformations done manually, as wiring Cursym is tricky.

Change-Id: Ief88b00b73904224675c0035684c3a84c19249d7
Reviewed-on: https://go-review.googlesource.com/29369Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Michael Hudson-Doyle <michael.hudson@canonical.com>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Change-Id: Icfb38f492ae71432858b7104fcba18a9ba835192
Reviewed-on: https://go-review.googlesource.com/29410Reviewed-by: Ian Lance Taylor <iant@golang.org>

At least, I assume it's meant to be here. It makes no sense at all where it
currently is.

Change-Id: Ic6a6c112c3dcf1318256d7d602168c3446b55412
Reviewed-on: https://go-review.googlesource.com/29339
Run-TryBot: Michael Hudson-Doyle <michael.hudson@canonical.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

Example on linux_amd64 for 'go tool vet -h':

Before:
	Usage of /usr/local/go/pkg/tool/linux_amd64/vet:
After:
	Usage of vet:

Change-Id: I11cb16b656bd097062d57a8c7441fbe66caaef78
Reviewed-on: https://go-review.googlesource.com/29294Reviewed-by: Rob Pike <r@golang.org>

The code scanned for an integer after a decimal point, which
meant things could overflow if the number was very precise
(0.1234123412341234123412342134s). This fix changes the
parser to stop adding precision once we run out of bits, rather
than trigger an erroneous overflow.

We could parse durations using floating-point arithmetic,
but since the type is int64 and float64 has only has 53 bits
of precision, that would be imprecise.

Fixes #15011.

Change-Id: If85e22b8f6cef12475e221169bb8f493bb9eb590
Reviewed-on: https://go-review.googlesource.com/29338Reviewed-by: Costin Chirvasuta <costinc@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Also adds the 'find leftmost one' instruction (FLOGR) and replaces the
WORD-encoded use of FLOGR in math/big with it.

Change-Id: I18e7cd19e75b8501a6ae8bd925471f7e37ded206
Reviewed-on: https://go-review.googlesource.com/29372Reviewed-by: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Michael Munday <munday@ca.ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

The current implementation for Power architecture does not include the vector
(Altivec) registers.  This adds the 32 VMX registers and the most commonly used
instructions: X-form loads/stores; VX-form logical operations, add/sub,
rotate/shift, count, splat, SHA Sigma and AES cipher; VC-form compare; and
VA-form permute, shift, add/sub and select.

Fixes #15619

Change-Id: I544b990631726e8fdfcce8ecca0aeeb72faae9aa
Reviewed-on: https://go-review.googlesource.com/25600
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Lynn Boger <laboger@linux.vnet.ibm.com>
Reviewed-by: David Chase <drchase@google.com>

Updates #16360.

Change-Id: I75714d2b5f095fe39fd81edfa6dd9e44d7c44da1
Reviewed-on: https://go-review.googlesource.com/29375
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

We're dropping this behavior in favor of runtime.KeepAlive.
Implement runtime.KeepAlive as an intrinsic.

Update #15843

Change-Id: Ib60225bd30d6770ece1c3c7d1339a06aa25b1cbc
Reviewed-on: https://go-review.googlesource.com/28310
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>

Change-Id: Ie1b08215c02ce3ec72a4752f4b800f23345ff99d
Reviewed-on: https://go-review.googlesource.com/29362Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

We compute a lot of stuff based off the CFG: postorder traversal,
dominators, dominator tree, loop nest.  Multiple phases use this
information and we end up recomputing some of it.  Add a cache
for this information so if the CFG hasn't changed, we can reuse
the previous computation.

Change-Id: I9b5b58af06830bd120afbee9cfab395a0a2f74b2
Reviewed-on: https://go-review.googlesource.com/29356Reviewed-by: David Chase <drchase@google.com>

Change-Id: I571f03af6f791e78e7e18addcc310eb25747cdcf
Reviewed-on: https://go-review.googlesource.com/29351Reviewed-by: David Chase <drchase@google.com>
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

No point in calling a function when we can build the interface
using a known type (or itab) and the address of a local.

Get rid of third arg (preallocated stack space) to convT2{I,E}.

Makes go binary smaller by 0.2%

benchmark                   old ns/op     new ns/op     delta
BenchmarkEfaceInteger-8     16.7          10.1          -39.52%

Update #17118
Update #15375

Change-Id: I9724a1f802bfa1e3957bf1856b55558278e198a2
Reviewed-on: https://go-review.googlesource.com/29373
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>

Was missing a title in the documentation, so it formatted wrong.

Fixes #17124

Change-Id: Ie8a9c36fbc54eed7d8a761f89a088e582b8c062d
Reviewed-on: https://go-review.googlesource.com/29340Reviewed-by: Andrew Gerrand <adg@golang.org>

They are trivially available in the few places they are needed.

Change-Id: I6544692e9027076ec9e6e9a295c66457039e55e1
Reviewed-on: https://go-review.googlesource.com/29332
Run-TryBot: Michael Hudson-Doyle <michael.hudson@canonical.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

Doing this revealed some dead code.

Change-Id: I5202fcc3f73e3dfddfea3ec7b772e16da51195da
Reviewed-on: https://go-review.googlesource.com/29331
Run-TryBot: Michael Hudson-Doyle <michael.hudson@canonical.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>