The Transport's writer to the remote server is wrapped in a
bufio.Writer to suppress many small writes while writing headers and
trailers. However, when writing the request body, the buffering may get
in the way if the request body is arriving slowly.

Because the io.Copy from the Request.Body to the writer is already
buffered, the outer bufio.Writer is unnecessary and prevents small
Request.Body.Reads from going to the server right away. (and the
io.Reader contract does say to return when you've got something,
instead of blocking waiting for more). After the body is finished, the
Transport's bufio.Writer is still used for any trailers following.

A previous attempted fix for this made the chunk writer always flush
if the underlying type was a bufio.Writer, but that is not quite
correct. This CL instead makes it opt-in by using a private sentinel
type (wrapping a *bufio.Writer) to the chunk writer that requests
Flushes after each chunk body (the chunk header & chunk body are still
buffered together into one write).

Fixes #6574

Change-Id: Icefcdf17130c9e285c80b69af295bfd3e72c3a70
Reviewed-on: https://go-review.googlesource.com/10021Reviewed-by: Andrew Gerrand <adg@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

I was previously setting GOARM=arm5 (due to confusion with previously
seeing buildall.sh's temporary of "arm5" as a GOARCH and
misremembernig), but GOARM=arm5 was acting like GOARM=5 only on
accident. See https://go-review.googlesource.com/#/c/10023/

Instead, fail if GOARM is not a known value.

Change-Id: I9ba4fd7268df233d40b09f0431f37cd85a049847
Reviewed-on: https://go-review.googlesource.com/10024Reviewed-by: Minux Ma <minux@golang.org>

Fixes #10735.

Change-Id: I5c6e424653657c89da176136ac56597c7565abe5
Reviewed-on: https://go-review.googlesource.com/10039Reviewed-by: Rob Pike <r@golang.org>

Fixes #10749

Change-Id: I9d5f6f179fd117b0c358d7c8042daf5985b645c0
Reviewed-on: https://go-review.googlesource.com/10022Reviewed-by: Dave Cheney <dave@cheney.net>

Change-Id: I6bda19877ae5148ad349cfb8929f1103740422bb
Reviewed-on: https://go-review.googlesource.com/10005Reviewed-by: Ian Lance Taylor <iant@golang.org>

Fixes #10796.

Change-Id: Ifcd2e771c64114e210fbfc5efaaceb53c534f745
Reviewed-on: https://go-review.googlesource.com/10007Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

'env' command is not available on some android devices.

Change-Id: I68b1152ef7ea248c8e80c7f71e97da76e3ec6394
Reviewed-on: https://go-review.googlesource.com/9999Reviewed-by: Minux Ma <minux@golang.org>

Was otherwise absent unless bound to an exported symbol,
as in the BUG with strings.Title.

Fixes #10781.

Change-Id: I1543137073a9dee9e546bc9d648ca54fc9632dde
Reviewed-on: https://go-review.googlesource.com/9899Reviewed-by: Russ Cox <rsc@golang.org>

Change-Id: Ic8ebbe81eb788626c01bfab238d54236e6e5ef2b
Reviewed-on: https://go-review.googlesource.com/9964
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>

The code generated for a slice x[i:j] or x[i:j:k] computes the entire
new slice (base, len, cap) and then uses it as the evaluation of the
slice expression.

If the slice is part of an update x = x[i:j] or x = x[i:j:k], there are
opportunities to avoid computing some of these fields.

For x = x[0:i], we know that only the len is changing;
base can be ignored completely, and cap can be left unmodified.

For x = x[0:i:j], we know that only len and cap are changing;
base can be ignored completely.

For x = x[i:i], we know that the resulting cap is zero, and we don't
adjust the base during a slice producing a zero-cap result,
so again base can be ignored completely.

No write to base, no write barrier.

The old slice code was trying to work at a Go syntax level, mainly
because that was how you wrote code just once instead of once
per architecture. Now the compiler is factored a bit better and we
can implement slice during code generation but still have one copy
of the code. So the new code is working at that lower level.
(It must, to update only parts of the result.)

This CL by itself:
name                   old mean              new mean              delta
BinaryTree17            5.81s × (0.98,1.03)   5.71s × (0.96,1.05)     ~    (p=0.101)
Fannkuch11              4.35s × (1.00,1.00)   4.39s × (1.00,1.00)   +0.79% (p=0.000)
FmtFprintfEmpty        86.0ns × (0.94,1.11)  82.6ns × (0.98,1.04)   -3.86% (p=0.048)
FmtFprintfString        276ns × (0.98,1.04)   273ns × (0.98,1.02)     ~    (p=0.235)
FmtFprintfInt           274ns × (0.98,1.06)   270ns × (0.99,1.01)     ~    (p=0.119)
FmtFprintfIntInt        506ns × (0.99,1.01)   475ns × (0.99,1.01)   -6.02% (p=0.000)
FmtFprintfPrefixedInt   391ns × (0.99,1.01)   393ns × (1.00,1.01)     ~    (p=0.139)
FmtFprintfFloat         566ns × (0.99,1.01)   574ns × (1.00,1.01)   +1.33% (p=0.001)
FmtManyArgs            1.91µs × (0.99,1.01)  1.87µs × (0.99,1.02)   -1.83% (p=0.000)
GobDecode              15.3ms × (0.99,1.02)  15.0ms × (0.98,1.05)   -1.84% (p=0.042)
GobEncode              11.5ms × (0.97,1.03)  11.4ms × (0.99,1.03)     ~    (p=0.152)
Gzip                    645ms × (0.99,1.01)   647ms × (0.99,1.01)     ~    (p=0.265)
Gunzip                  142ms × (1.00,1.00)   143ms × (1.00,1.01)   +0.90% (p=0.000)
HTTPClientServer       90.5µs × (0.97,1.04)  88.5µs × (0.99,1.03)   -2.27% (p=0.014)
JSONEncode             32.0ms × (0.98,1.03)  29.6ms × (0.98,1.01)   -7.51% (p=0.000)
JSONDecode              114ms × (0.99,1.01)   104ms × (1.00,1.01)   -8.60% (p=0.000)
Mandelbrot200          6.04ms × (1.00,1.01)  6.02ms × (1.00,1.00)     ~    (p=0.057)
GoParse                6.47ms × (0.97,1.05)  6.37ms × (0.97,1.04)     ~    (p=0.105)
RegexpMatchEasy0_32     171ns × (0.93,1.07)   152ns × (0.99,1.01)  -11.09% (p=0.000)
RegexpMatchEasy0_1K     550ns × (0.98,1.01)   530ns × (1.00,1.00)   -3.78% (p=0.000)
RegexpMatchEasy1_32     135ns × (0.99,1.02)   134ns × (0.99,1.01)   -1.33% (p=0.002)
RegexpMatchEasy1_1K     879ns × (1.00,1.01)   865ns × (1.00,1.00)   -1.58% (p=0.000)
RegexpMatchMedium_32    243ns × (1.00,1.00)   233ns × (1.00,1.00)   -4.30% (p=0.000)
RegexpMatchMedium_1K   70.3µs × (1.00,1.00)  69.5µs × (1.00,1.00)   -1.13% (p=0.000)
RegexpMatchHard_32     3.82µs × (1.00,1.01)  3.74µs × (1.00,1.00)   -1.95% (p=0.000)
RegexpMatchHard_1K      117µs × (1.00,1.00)   115µs × (1.00,1.00)   -1.69% (p=0.000)
Revcomp                 917ms × (0.97,1.04)   920ms × (0.97,1.04)     ~    (p=0.786)
Template                114ms × (0.99,1.01)   117ms × (0.99,1.01)   +2.58% (p=0.000)
TimeParse               622ns × (0.99,1.01)   615ns × (0.99,1.00)   -1.06% (p=0.000)
TimeFormat              665ns × (0.99,1.01)   654ns × (0.99,1.00)   -1.70% (p=0.000)

This CL and previous CL (append) combined:
name                   old mean              new mean              delta
BinaryTree17            5.68s × (0.97,1.04)   5.71s × (0.96,1.05)     ~    (p=0.638)
Fannkuch11              4.41s × (0.98,1.03)   4.39s × (1.00,1.00)     ~    (p=0.474)
FmtFprintfEmpty        92.7ns × (0.91,1.16)  82.6ns × (0.98,1.04)  -10.89% (p=0.004)
FmtFprintfString        281ns × (0.96,1.08)   273ns × (0.98,1.02)     ~    (p=0.078)
FmtFprintfInt           288ns × (0.97,1.06)   270ns × (0.99,1.01)   -6.37% (p=0.000)
FmtFprintfIntInt        493ns × (0.97,1.04)   475ns × (0.99,1.01)   -3.53% (p=0.002)
FmtFprintfPrefixedInt   423ns × (0.97,1.04)   393ns × (1.00,1.01)   -7.07% (p=0.000)
FmtFprintfFloat         598ns × (0.99,1.01)   574ns × (1.00,1.01)   -4.02% (p=0.000)
FmtManyArgs            1.89µs × (0.98,1.05)  1.87µs × (0.99,1.02)     ~    (p=0.305)
GobDecode              14.8ms × (0.98,1.03)  15.0ms × (0.98,1.05)     ~    (p=0.237)
GobEncode              12.3ms × (0.98,1.01)  11.4ms × (0.99,1.03)   -6.95% (p=0.000)
Gzip                    656ms × (0.99,1.05)   647ms × (0.99,1.01)     ~    (p=0.101)
Gunzip                  142ms × (1.00,1.00)   143ms × (1.00,1.01)   +0.58% (p=0.001)
HTTPClientServer       91.2µs × (0.97,1.04)  88.5µs × (0.99,1.03)   -3.02% (p=0.003)
JSONEncode             32.6ms × (0.97,1.08)  29.6ms × (0.98,1.01)   -9.10% (p=0.000)
JSONDecode              114ms × (0.97,1.05)   104ms × (1.00,1.01)   -8.74% (p=0.000)
Mandelbrot200          6.11ms × (0.98,1.04)  6.02ms × (1.00,1.00)     ~    (p=0.090)
GoParse                6.66ms × (0.97,1.04)  6.37ms × (0.97,1.04)   -4.41% (p=0.000)
RegexpMatchEasy0_32     159ns × (0.99,1.00)   152ns × (0.99,1.01)   -4.69% (p=0.000)
RegexpMatchEasy0_1K     538ns × (1.00,1.01)   530ns × (1.00,1.00)   -1.57% (p=0.000)
RegexpMatchEasy1_32     138ns × (1.00,1.00)   134ns × (0.99,1.01)   -2.91% (p=0.000)
RegexpMatchEasy1_1K     869ns × (0.99,1.01)   865ns × (1.00,1.00)   -0.51% (p=0.012)
RegexpMatchMedium_32    252ns × (0.99,1.01)   233ns × (1.00,1.00)   -7.85% (p=0.000)
RegexpMatchMedium_1K   72.7µs × (1.00,1.00)  69.5µs × (1.00,1.00)   -4.43% (p=0.000)
RegexpMatchHard_32     3.85µs × (1.00,1.00)  3.74µs × (1.00,1.00)   -2.74% (p=0.000)
RegexpMatchHard_1K      118µs × (1.00,1.00)   115µs × (1.00,1.00)   -2.24% (p=0.000)
Revcomp                 920ms × (0.97,1.07)   920ms × (0.97,1.04)     ~    (p=0.998)
Template                129ms × (0.98,1.03)   117ms × (0.99,1.01)   -9.79% (p=0.000)
TimeParse               619ns × (0.99,1.01)   615ns × (0.99,1.00)   -0.57% (p=0.011)
TimeFormat              661ns × (0.98,1.04)   654ns × (0.99,1.00)     ~    (p=0.223)

Change-Id: If054d81ab2c71d8d62cf54b5b1fac2af66b387fc
Reviewed-on: https://go-review.googlesource.com/9813Reviewed-by: David Chase <drchase@google.com>
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

The spec explains later in the "Operator precedence" section that *
has a higher precedence than +, but the current production rule
requires that "1 + 2 * 3" be parsed as "(1 + 2) * 3", instead of the
intended "1 + (2 * 3)".

The new production rule better matches cmd/internal/gc/go.y's grammar:

    expr:
            uexpr
    |       expr LOROR expr
    |       expr LANDAND expr
    |       ...

Fixes #10151.

Change-Id: I13c9635d6ddf1263cafe7cc63e68f3e5779e24ba
Reviewed-on: https://go-review.googlesource.com/9163Reviewed-by: Robert Griesemer <gri@golang.org>

Set overflowing integer constants to 1 rather than 0 to avoid
spurious div-zero errors in subsequent constant expressions.

Also: Exclude new test case from go/types test since it's
running too long (go/types doesn't have an upper constant
size limit at the moment).

Fixes #7746.

Change-Id: I3768488ad9909a3cf995247b81ee78a8eb5a1e41
Reviewed-on: https://go-review.googlesource.com/9165
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>

One important use case is a pipeline computation that pass values
from one Goroutine to the next and then exits or is placed in a
wait state. If GOMAXPROCS > 1 a Goroutine running on P1 will enable
another Goroutine and then immediately make P1 available to execute
it. We need to prevent other Ps from stealing the G that P1 is about
to execute. Otherwise the Gs can thrash between Ps causing unneeded
synchronization and slowing down throughput.

Fix this by changing the stealing logic so that when a P attempts to
steal the only G on some other P's run queue, it will pause
momentarily to allow the victim P to schedule the G.

As part of optimizing stealing we also use a per P victim queue
move stolen gs. This eliminates the zeroing of a stack local victim
queue which turned out to be expensive.

This CL is a necessary but not sufficient prerequisite to changing
the default value of GOMAXPROCS to something > 1 which is another
CL/discussion.

For highly serialized programs, such as GoroutineRing below this can
make a large difference. For larger and more parallel programs such
as the x/benchmarks there is no noticeable detriment.

~/work/code/src/rsc.io/benchstat/benchstat old.txt new.txt
name                old mean              new mean              delta
GoroutineRing       30.2µs × (0.98,1.01)  30.1µs × (0.97,1.04)     ~    (p=0.941)
GoroutineRing-2      113µs × (0.91,1.07)    30µs × (0.98,1.03)  -73.17% (p=0.004)
GoroutineRing-4      144µs × (0.98,1.02)    32µs × (0.98,1.01)  -77.69% (p=0.000)
GoroutineRingBuf    32.7µs × (0.97,1.03)  32.5µs × (0.97,1.02)     ~    (p=0.795)
GoroutineRingBuf-2   120µs × (0.92,1.08)    33µs × (1.00,1.00)  -72.48% (p=0.004)
GoroutineRingBuf-4   138µs × (0.92,1.06)    33µs × (1.00,1.00)  -76.21% (p=0.003)

The bench benchmarks show little impact.
    	  	      old  	 new
garbage	      	      7032879	 7011696
httpold		        25509	   25301
splayold	      1022073	 1019499
jsonold		     28230624   28081433

Change-Id: I228c48fed8d85c9bbef16a7edc53ab7898506f50
Reviewed-on: https://go-review.googlesource.com/9872Reviewed-by: Austin Clements <austin@google.com>

Fixes #10787.

Change-Id: I35c96808a713dafb1f0fea301fa3f3528fe6a5bf
Reviewed-on: https://go-review.googlesource.com/9948Reviewed-by: Alex Brainman <alex.brainman@gmail.com>

FileConn and FilePacketConn APIs accept user-configured socket
descriptors to make them work together with runtime-integrated network
poller, but there's a limitation. The APIs reject protocol sockets that
are not supported by standard library. It's very hard for the net,
syscall packages to look after all platform, feature-specific sockets.

This change allows various platform, feature-specific socket descriptors
to use runtime-integrated network poller by using SocketConn,
SocketPacketConn APIs that bridge between the net, syscall packages and
platforms.

New exposed APIs:
pkg net, func SocketConn(*os.File, SocketAddr) (Conn, error)
pkg net, func SocketPacketConn(*os.File, SocketAddr) (PacketConn, error)
pkg net, type SocketAddr interface { Addr, Raw }
pkg net, type SocketAddr interface, Addr([]uint8) Addr
pkg net, type SocketAddr interface, Raw(Addr) []uint8

Fixes #10565.

Change-Id: Iec57499b3d84bb5cb0bcf3f664330c535eec11e3
Reviewed-on: https://go-review.googlesource.com/9275Reviewed-by: Ian Lance Taylor <iant@golang.org>

If __LP64__ is defined then the type "long" is 64-bits, and there is
no need to explicitly request _FILE_OFFSET_BITS == 64.  This changes
the definitions of F_GETLK, F_SETLK, and F_SETLKW on PPC to the values
that the kernel requires.  The values used in C when _FILE_OFFSET_BITS
== 64 are corrected by the glibc fcntl function before making the
system call.

With this change, regenerate ppc64le files on Ubuntu trusty.

Change-Id: I8dddbd8a6bae877efff818f5c5dd06291ade3238
Reviewed-on: https://go-review.googlesource.com/9962Reviewed-by: Minux Ma <minux@golang.org>

On android the generated header files are located in
pkg/$(go env GOOS)_$(go env GOARCH)_testcshared.
The test was broken since https://go-review.googlesource.com/9798.

The installation path differs based on codegenArgs
(around src/cmd/go/build.go line 389), and the codegenArgs
is platform dependent.

Change-Id: I01ae9cb957fb7676e399f3b8c067f24c5bd20b9d
Reviewed-on: https://go-review.googlesource.com/9980Reviewed-by: Ian Lance Taylor <iant@golang.org>

Fixes #10794.

Change-Id: Id91485394ddbadc28c800e1d0c3ec281ba6cd098
Reviewed-on: https://go-review.googlesource.com/9990Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

This will skip system call numbers that are ifdef'ed out in unistd.h,
as occurs on PPC.

Change-Id: I88e640e4621c7a8cc266433f34a7b4be71543ec9
Reviewed-on: https://go-review.googlesource.com/9966Reviewed-by: Minux Ma <minux@golang.org>

Running these tests on the system stack is problematic because they
allocate Ps, which are large enough to overflow the system stack if
they are stack-allocated. It used to be necessary to run these tests
on the system stack because they were written in C, but since this is
no longer the case, we can fix this problem by simply not running the
tests on the system stack.

This also means we no longer need the hack in one of these tests that
forces the allocated Ps to escape to the heap, so eliminate that as
well.

Change-Id: I9064f5f8fd7f7b446ff39a22a70b172cfcb2dc57
Reviewed-on: https://go-review.googlesource.com/9923Reviewed-by: Rick Hudson <rlh@golang.org>
Run-TryBot: Austin Clements <austin@google.com>

The line in cgen.go was lost during the ginscmp CL.
The ggen.go change is not strictly necessary, but
it makes the 5g -S output for x[0] match what it said
before the ginscmp CL.

Change-Id: I5890a9ec1ac69a38509416eda5aea13b8b12b94a
Reviewed-on: https://go-review.googlesource.com/9929Reviewed-by: Russ Cox <rsc@golang.org>

Fix bug on Linux SysProcAttr handling: setting both Pdeathsig and
Credential caused Pdeathsig to be ignored. This is because the kernel
clears the deathsignal field when performing a setuid/setgid
system call.

Avoid this by moving Pdeathsig handling after Credential handling.

Fixes #9686

Change-Id: Id01896ad4e979b8c448e0061f00aa8762ca0ac94
Reviewed-on: https://go-review.googlesource.com/3290Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

The code generated for x = append(x, v) is roughly:

	t := x
	if len(t)+1 > cap(t) {
		t = grow(t)
	}
	t[len(t)] = v
	len(t)++
	x = t

We used to generate this code as Go pseudocode during walk.
Generate it instead as actual instructions during gen.

Doing so lets us apply a few optimizations. The most important
is that when, as in the above example, the source slice and the
destination slice are the same, the code can instead do:

	t := x
	if len(t)+1 > cap(t) {
		t = grow(t)
		x = {base(t), len(t)+1, cap(t)}
	} else {
		len(x)++
	}
	t[len(t)] = v

That is, in the fast path that does not reallocate the array,
only the updated length needs to be written back to x,
not the array pointer and not the capacity. This is more like
what you'd write by hand in C. It's faster in general, since
the fast path elides two of the three stores, but it's especially
faster when the form of x is such that the base pointer write
would turn into a write barrier. No write, no barrier.

name                   old mean              new mean              delta
BinaryTree17            5.68s × (0.97,1.04)   5.81s × (0.98,1.03)   +2.35% (p=0.023)
Fannkuch11              4.41s × (0.98,1.03)   4.35s × (1.00,1.00)     ~    (p=0.090)
FmtFprintfEmpty        92.7ns × (0.91,1.16)  86.0ns × (0.94,1.11)   -7.31% (p=0.038)
FmtFprintfString        281ns × (0.96,1.08)   276ns × (0.98,1.04)     ~    (p=0.219)
FmtFprintfInt           288ns × (0.97,1.06)   274ns × (0.98,1.06)   -4.94% (p=0.002)
FmtFprintfIntInt        493ns × (0.97,1.04)   506ns × (0.99,1.01)   +2.65% (p=0.009)
FmtFprintfPrefixedInt   423ns × (0.97,1.04)   391ns × (0.99,1.01)   -7.52% (p=0.000)
FmtFprintfFloat         598ns × (0.99,1.01)   566ns × (0.99,1.01)   -5.27% (p=0.000)
FmtManyArgs            1.89µs × (0.98,1.05)  1.91µs × (0.99,1.01)     ~    (p=0.231)
GobDecode              14.8ms × (0.98,1.03)  15.3ms × (0.99,1.02)   +3.01% (p=0.000)
GobEncode              12.3ms × (0.98,1.01)  11.5ms × (0.97,1.03)   -5.93% (p=0.000)
Gzip                    656ms × (0.99,1.05)   645ms × (0.99,1.01)     ~    (p=0.055)
Gunzip                  142ms × (1.00,1.00)   142ms × (1.00,1.00)   -0.32% (p=0.034)
HTTPClientServer       91.2µs × (0.97,1.04)  90.5µs × (0.97,1.04)     ~    (p=0.468)
JSONEncode             32.6ms × (0.97,1.08)  32.0ms × (0.98,1.03)     ~    (p=0.190)
JSONDecode              114ms × (0.97,1.05)   114ms × (0.99,1.01)     ~    (p=0.887)
Mandelbrot200          6.11ms × (0.98,1.04)  6.04ms × (1.00,1.01)     ~    (p=0.167)
GoParse                6.66ms × (0.97,1.04)  6.47ms × (0.97,1.05)   -2.81% (p=0.014)
RegexpMatchEasy0_32     159ns × (0.99,1.00)   171ns × (0.93,1.07)   +7.19% (p=0.002)
RegexpMatchEasy0_1K     538ns × (1.00,1.01)   550ns × (0.98,1.01)   +2.30% (p=0.000)
RegexpMatchEasy1_32     138ns × (1.00,1.00)   135ns × (0.99,1.02)   -1.60% (p=0.000)
RegexpMatchEasy1_1K     869ns × (0.99,1.01)   879ns × (1.00,1.01)   +1.08% (p=0.000)
RegexpMatchMedium_32    252ns × (0.99,1.01)   243ns × (1.00,1.00)   -3.71% (p=0.000)
RegexpMatchMedium_1K   72.7µs × (1.00,1.00)  70.3µs × (1.00,1.00)   -3.34% (p=0.000)
RegexpMatchHard_32     3.85µs × (1.00,1.00)  3.82µs × (1.00,1.01)   -0.81% (p=0.000)
RegexpMatchHard_1K      118µs × (1.00,1.00)   117µs × (1.00,1.00)   -0.56% (p=0.000)
Revcomp                 920ms × (0.97,1.07)   917ms × (0.97,1.04)     ~    (p=0.808)
Template                129ms × (0.98,1.03)   114ms × (0.99,1.01)  -12.06% (p=0.000)
TimeParse               619ns × (0.99,1.01)   622ns × (0.99,1.01)     ~    (p=0.062)
TimeFormat              661ns × (0.98,1.04)   665ns × (0.99,1.01)     ~    (p=0.524)

See next CL for combination with a similar optimization for slice.
The benchmarks that are slower in this CL are still faster overall
with the combination of the two.

Change-Id: I2a7421658091b2488c64741b4db15ab6c3b4cb7e
Reviewed-on: https://go-review.googlesource.com/9812Reviewed-by: David Chase <drchase@google.com>

This lets us abstract away which arguments can be constants and so on
and lets the back ends reverse the order of arguments if that helps.

Change-Id: I283ec1d694f2dd84eba22e5eb4aad78a2d2d9eb0
Reviewed-on: https://go-review.googlesource.com/9810Reviewed-by: David Chase <drchase@google.com>

Messages that are too big are rejected when read, so they should
be rejected when written too.

Fixes #10518.

Change-Id: I96678fbe2d94f51b957fe26faef33cd8df3823dd
Reviewed-on: https://go-review.googlesource.com/9965Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

The status buffer built by the exit function
was not nil-terminated.

Fixes #10789.

Change-Id: I2d34ac50a19d138176c4b47393497ba7070d5b61
Reviewed-on: https://go-review.googlesource.com/9953Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>

Once added to the signal queue, the pointer passed to the
signal handler could no longer be valid. Instead of passing
the pointer to the note string, we recopy the value of the
note string to a static array in the signal queue.

Fixes #10784.

Change-Id: Iddd6837b58a14dfaa16b069308ae28a7b8e0965b
Reviewed-on: https://go-review.googlesource.com/9950Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

This slows down more things than I expected, but it also speeds things up,
and it reduces stack frame sizes and the load on the optimizer, so it's still
likely a net win.

name                                    old mean                new mean        delta
BenchmarkBinaryTree17              13.2s × (0.98,1.03)     13.2s × (0.98,1.02)  ~ (p=0.795)
BenchmarkFannkuch11                4.41s × (1.00,1.00)     4.45s × (0.99,1.01)  +0.88% (p=0.000)
BenchmarkFmtFprintfEmpty          86.4ns × (0.99,1.01)    90.1ns × (0.95,1.05)  +4.31% (p=0.000)
BenchmarkFmtFprintfString          318ns × (0.96,1.07)     337ns × (0.98,1.03)  +6.05% (p=0.000)
BenchmarkFmtFprintfInt             332ns × (0.97,1.04)     320ns × (0.97,1.02)  -3.42% (p=0.000)
BenchmarkFmtFprintfIntInt          562ns × (0.96,1.04)     574ns × (0.96,1.06)  +2.00% (p=0.013)
BenchmarkFmtFprintfPrefixedInt     442ns × (0.96,1.06)     450ns × (0.97,1.05)  +1.73% (p=0.039)
BenchmarkFmtFprintfFloat           640ns × (0.99,1.02)     659ns × (0.99,1.03)  +3.01% (p=0.000)
BenchmarkFmtManyArgs              2.19µs × (0.97,1.06)    2.21µs × (0.98,1.02)  ~ (p=0.104)
BenchmarkGobDecode                20.0ms × (0.98,1.03)    19.7ms × (0.97,1.04)  -1.35% (p=0.035)
BenchmarkGobEncode                17.8ms × (0.96,1.04)    18.0ms × (0.96,1.06)  ~ (p=0.131)
BenchmarkGzip                      653ms × (0.99,1.02)     652ms × (0.99,1.01)  ~ (p=0.572)
BenchmarkGunzip                    143ms × (0.99,1.02)     142ms × (1.00,1.01)  -0.52% (p=0.005)
BenchmarkHTTPClientServer          110µs × (0.98,1.03)     108µs × (0.99,1.02)  -1.90% (p=0.000)
BenchmarkJSONEncode               40.0ms × (0.98,1.05)    41.5ms × (0.97,1.06)  +3.89% (p=0.000)
BenchmarkJSONDecode                118ms × (0.99,1.01)     118ms × (0.98,1.01)  +0.69% (p=0.010)
BenchmarkMandelbrot200            6.03ms × (1.00,1.01)    6.03ms × (1.00,1.01)  ~ (p=0.924)
BenchmarkGoParse                  8.43ms × (0.92,1.11)    8.56ms × (0.93,1.05)  ~ (p=0.242)
BenchmarkRegexpMatchEasy0_32       180ns × (0.91,1.07)     163ns × (1.00,1.00)  -9.33% (p=0.000)
BenchmarkRegexpMatchEasy0_1K       550ns × (0.98,1.02)     558ns × (0.99,1.01)  +1.44% (p=0.000)
BenchmarkRegexpMatchEasy1_32       152ns × (0.94,1.05)     139ns × (0.98,1.02)  -8.51% (p=0.000)
BenchmarkRegexpMatchEasy1_1K       909ns × (0.98,1.06)     868ns × (0.99,1.02)  -4.52% (p=0.000)
BenchmarkRegexpMatchMedium_32      262ns × (0.97,1.03)     253ns × (0.99,1.02)  -3.31% (p=0.000)
BenchmarkRegexpMatchMedium_1K     73.8µs × (0.98,1.04)    72.7µs × (1.00,1.01)  -1.61% (p=0.001)
BenchmarkRegexpMatchHard_32       3.87µs × (0.99,1.02)    3.87µs × (1.00,1.01)  ~ (p=0.791)
BenchmarkRegexpMatchHard_1K        118µs × (0.98,1.04)     117µs × (0.99,1.02)  ~ (p=0.110)
BenchmarkRevcomp                   1.00s × (0.94,1.10)     0.99s × (0.94,1.09)  ~ (p=0.433)
BenchmarkTemplate                  140ms × (0.97,1.04)     140ms × (0.99,1.01)  ~ (p=0.303)
BenchmarkTimeParse                 622ns × (0.99,1.02)     625ns × (0.99,1.01)  +0.51% (p=0.001)
BenchmarkTimeFormat                731ns × (0.98,1.04)     719ns × (0.99,1.01)  -1.66% (p=0.000)

Change-Id: Ibc3edb59a178adafda50156f46a341f69a17d83f
Reviewed-on: https://go-review.googlesource.com/9721Reviewed-by: David Chase <drchase@google.com>

Today's earlier fix can stay, but it's a band-aid over the real problem,
which is that bad code was slipping through the type checker
into the back end (and luckily causing a type error there).

I discovered this because my new append does not use the same
temporaries and failed the test as written.

Fixes #9521.

Change-Id: I7e33e2ea15743406e15c6f3fdf73e1edecda69bd
Reviewed-on: https://go-review.googlesource.com/9921Reviewed-by: Ian Lance Taylor <iant@golang.org>

Any Git branch can be the default branch not only master. Removing
hardwired 'checkout master', and using 'checkout {tag}' is the best
choice. It works with and without a master branch. Furthermore it
resolves the Github default branch issue. Changing Github default
branch is effectively changing HEAD.

Fixes #9032

Change-Id: I19a1221bcefe0806e7556c124c6da7ac0c2160b5
Reviewed-on: https://go-review.googlesource.com/5312Reviewed-by: Russ Cox <rsc@golang.org>

registry.ReadSubKeyNames requires QUERY access right in addition to
ENUMERATE_SUB_KEYS.

This was making TestLocalZoneAbbr fail on Windows 7 in Paris/Madrid
timezone. It succeeded on Windows 8 because timezone name changed from
"Paris/Madrid" to "Romance Standard Time", the latter being matched by
an abbrs entry.

Change-Id: I791287ba9d1b3556246fa4e9e1604a1fbba1f5e6
Reviewed-on: https://go-review.googlesource.com/9809Reviewed-by: Alex Brainman <alex.brainman@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

TestAcceptIgnoreSomeErrors was created to test that network
accept function ignores some errors. But conditions created
by the test also affects network reads. Change the test to
ignore these read errors when acceptable.

Fixes #10785

Change-Id: I3da85cb55bd3e78c1980ad949e53e82391f9b41e
Reviewed-on: https://go-review.googlesource.com/9942Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Change-Id: I58c6e914d0e977d5748c87d277e30c933ed86f99
Reviewed-on: https://go-review.googlesource.com/9924Reviewed-by: Ian Lance Taylor <iant@golang.org>

This:

1) Defines the ABI hash of a package (as the SHA1 of the __.PKGDEF)
2) Defines the ABI hash of a shared library (sort the packages by import
   path, concatenate the hashes of the packages and SHA1 that)
3) When building a shared library, compute the above value and define a
   global symbol that points to a go string that has the hash as its value.
4) When linking against a shared library, read the abi hash from the
   library and put both the value seen at link time and a reference
   to the global symbol into the moduledata.
5) During runtime initialization, check that the hash seen at link time
   still matches the hash the global symbol points to.

Change-Id: Iaa54c783790e6dde3057a2feadc35473d49614a5
Reviewed-on: https://go-review.googlesource.com/8773Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Michael Hudson-Doyle <michael.hudson@canonical.com>

addmoduledata is called from a .init_array function and need to follow the
platform ABI. It contains accesses to global data which are rewritten to use
R15 by the assembler, and as R15 is callee-save we need to save it.

Change-Id: I03893efb1576aed4f102f2465421f256f3bb0f30
Reviewed-on: https://go-review.googlesource.com/9941Reviewed-by: Ian Lance Taylor <iant@golang.org>

Change-Id: I9b058472f5b4943db6e6f1c1243411ce61624c18
Reviewed-on: https://go-review.googlesource.com/9916Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Change-Id: I89778988baec1cf4a35d9342c7dbe8c4c08ff3cd
Reviewed-on: https://go-review.googlesource.com/9893
Run-TryBot: Hyang-Ah Hana Kim <hyangah@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Hyang-Ah Hana Kim <hyangah@gmail.com>

Change-Id: I4b1ce33253890de9bc64fee9b476fe52eec87fc0
Reviewed-on: https://go-review.googlesource.com/9920Reviewed-by: Russ Cox <rsc@golang.org>
Reviewed-by: Rob Pike <r@golang.org>

Fixes #4943
Fixes #4687
Fixes #7079

Change-Id: Ia96f07d650a3af935cd75fd7e3253f4af2977429
Reviewed-on: https://go-review.googlesource.com/7890Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>

Fixes #10770.
Fixes #10771.

This time maybe for sure?

Change-Id: I43d6e5fd6846cf58427fec183832d500a932df59
Reviewed-on: https://go-review.googlesource.com/9896Reviewed-by: Russ Cox <rsc@golang.org>