This behavior is the same as in Go: constants can be coerced to int
and whether overflow occurs depends on how big an int is, but
this surprises people sometimes, so document it again here.

Fixes #25833.

Change-Id: I557995f1a1e8e871b21004953923d16f36cb9037
Reviewed-on: https://go-review.googlesource.com/c/141378Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Nothing is changing but the documentation, which did not mention
this property of these functions.

Fixes #27587.

Change-Id: I75bcee4a1dd9ec8cd82826c9a6e02ba7d599f719
Reviewed-on: https://go-review.googlesource.com/c/141377Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

This CL optimize ADDLconstmodifyidx4 to INCL/DECL, when the
constant is +1/-1.

1. The total size of pkg/linux_386/ decreases 28 bytes, excluding
cmd/compile.

2. There is no regression in the go1 benchmark test, excluding noise.
name                     old time/op    new time/op    delta
BinaryTree17-4              3.25s ± 2%     3.23s ± 3%  -0.70%  (p=0.040 n=30+30)
Fannkuch11-4                3.50s ± 1%     3.47s ± 1%  -0.68%  (p=0.000 n=30+30)
FmtFprintfEmpty-4          44.6ns ± 3%    44.8ns ± 3%  +0.46%  (p=0.029 n=30+30)
FmtFprintfString-4         79.0ns ± 3%    78.7ns ± 3%    ~     (p=0.053 n=30+30)
FmtFprintfInt-4            89.2ns ± 2%    89.4ns ± 3%    ~     (p=0.665 n=30+29)
FmtFprintfIntInt-4          142ns ± 3%     142ns ± 3%    ~     (p=0.435 n=30+30)
FmtFprintfPrefixedInt-4     182ns ± 2%     182ns ± 2%    ~     (p=0.964 n=30+30)
FmtFprintfFloat-4           407ns ± 3%     411ns ± 4%    ~     (p=0.080 n=30+30)
FmtManyArgs-4               597ns ± 3%     593ns ± 4%    ~     (p=0.222 n=30+30)
GobDecode-4                7.09ms ± 6%    7.07ms ± 7%    ~     (p=0.633 n=30+30)
GobEncode-4                6.81ms ± 9%    6.81ms ± 8%    ~     (p=0.982 n=30+30)
Gzip-4                      398ms ± 4%     400ms ± 6%    ~     (p=0.177 n=30+30)
Gunzip-4                   41.3ms ± 3%    40.6ms ± 4%  -1.71%  (p=0.005 n=30+30)
HTTPClientServer-4         63.4µs ± 3%    63.4µs ± 4%    ~     (p=0.646 n=30+28)
JSONEncode-4               16.0ms ± 3%    16.1ms ± 3%    ~     (p=0.057 n=30+30)
JSONDecode-4               63.3ms ± 8%    63.1ms ± 7%    ~     (p=0.786 n=30+30)
Mandelbrot200-4            5.17ms ± 3%    5.15ms ± 8%    ~     (p=0.654 n=30+30)
GoParse-4                  3.24ms ± 3%    3.23ms ± 2%    ~     (p=0.091 n=30+30)
RegexpMatchEasy0_32-4       103ns ± 4%     103ns ± 4%    ~     (p=0.575 n=30+30)
RegexpMatchEasy0_1K-4       823ns ± 2%     821ns ± 3%    ~     (p=0.827 n=30+30)
RegexpMatchEasy1_32-4       113ns ± 3%     112ns ± 3%    ~     (p=0.076 n=30+30)
RegexpMatchEasy1_1K-4      1.02µs ± 4%    1.01µs ± 5%    ~     (p=0.087 n=30+30)
RegexpMatchMedium_32-4      129ns ± 3%     127ns ± 4%  -1.55%  (p=0.009 n=30+30)
RegexpMatchMedium_1K-4     39.3µs ± 4%    39.7µs ± 3%    ~     (p=0.054 n=30+30)
RegexpMatchHard_32-4       2.15µs ± 4%    2.15µs ± 4%    ~     (p=0.712 n=30+30)
RegexpMatchHard_1K-4       66.0µs ± 3%    65.1µs ± 3%  -1.32%  (p=0.002 n=30+30)
Revcomp-4                   1.85s ± 2%     1.85s ± 3%    ~     (p=0.168 n=30+30)
Template-4                 69.5ms ± 7%    68.9ms ± 6%    ~     (p=0.250 n=28+28)
TimeParse-4                 434ns ± 3%     432ns ± 4%    ~     (p=0.629 n=30+30)
TimeFormat-4                403ns ± 4%     408ns ± 3%  +1.23%  (p=0.019 n=30+29)
[Geo mean]                 65.5µs         65.3µs       -0.20%

name                     old speed      new speed      delta
GobDecode-4               108MB/s ± 6%   109MB/s ± 6%    ~     (p=0.636 n=30+30)
GobEncode-4               113MB/s ±10%   113MB/s ± 9%    ~     (p=0.982 n=30+30)
Gzip-4                   48.8MB/s ± 4%  48.6MB/s ± 5%    ~     (p=0.178 n=30+30)
Gunzip-4                  470MB/s ± 3%   479MB/s ± 4%  +1.72%  (p=0.006 n=30+30)
JSONEncode-4              121MB/s ± 3%   120MB/s ± 3%    ~     (p=0.057 n=30+30)
JSONDecode-4             30.7MB/s ± 8%  30.8MB/s ± 8%    ~     (p=0.784 n=30+30)
GoParse-4                17.9MB/s ± 3%  17.9MB/s ± 2%    ~     (p=0.090 n=30+30)
RegexpMatchEasy0_32-4     309MB/s ± 4%   309MB/s ± 3%    ~     (p=0.530 n=30+30)
RegexpMatchEasy0_1K-4    1.24GB/s ± 2%  1.25GB/s ± 3%    ~     (p=0.976 n=30+30)
RegexpMatchEasy1_32-4     282MB/s ± 3%   284MB/s ± 3%  +0.81%  (p=0.041 n=30+30)
RegexpMatchEasy1_1K-4    1.00GB/s ± 3%  1.01GB/s ± 4%    ~     (p=0.091 n=30+30)
RegexpMatchMedium_32-4   7.71MB/s ± 3%  7.84MB/s ± 4%  +1.71%  (p=0.000 n=30+30)
RegexpMatchMedium_1K-4   26.1MB/s ± 4%  25.8MB/s ± 3%    ~     (p=0.051 n=30+30)
RegexpMatchHard_32-4     14.9MB/s ± 4%  14.9MB/s ± 4%    ~     (p=0.712 n=30+30)
RegexpMatchHard_1K-4     15.5MB/s ± 3%  15.7MB/s ± 3%  +1.34%  (p=0.003 n=30+30)
Revcomp-4                 138MB/s ± 2%   137MB/s ± 3%    ~     (p=0.174 n=30+30)
Template-4               28.0MB/s ± 6%  28.2MB/s ± 6%    ~     (p=0.251 n=28+28)
[Geo mean]               82.3MB/s       82.6MB/s       +0.36%

Change-Id: I389829699ffe9500a013fcf31be58a97e98043e1
Reviewed-on: https://go-review.googlesource.com/c/140701
Run-TryBot: Ben Shi <powerman1st@163.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>

Forgot to do this for golang.org/cl/76312.

Change-Id: Ic20fef3eeff14a805f608221aff1fa03934be3ca
Reviewed-on: https://go-review.googlesource.com/c/141357
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

It's long-desired but was blocked by #26835. That is now fixed, so
it's easy. When -src is off, we behave as before. But with -src
set, initialize the go/doc package to preserve the original AST and
things flow very easily.

With -src, since you're seeing inside the package source anyway it
shows unexported fields and constants: you see the original source.
But you still need -u to ask about them.

Fixes #18807

Change-Id: I473e90323b4eff0735360274dc0d2d9dba16ff8b
Reviewed-on: https://go-review.googlesource.com/c/140959Reviewed-by: Andrew Gerrand <adg@golang.org>
Run-TryBot: Andrew Gerrand <adg@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

To save memory in godoc, this package routinely clears fields of
the AST to avoid keeping data that godoc no longer needs. For other
programs, such as cmd/doc, this behavior is unfortunate. Also, one
should be able to tell any package like this, "don't change my
data".

Add a Mode bit, defaulting to off to preserve existing behavior,
that allows a client to specify that the AST is inviolate.

This is necessary to address some of the outstanding issues
in cmd/doc that require, for example, looking at function bodies.

Fixes #26835

Change-Id: I01cc97c6addc5ab6abff885fff4bd53454a03bbc
Reviewed-on: https://go-review.googlesource.com/c/140958Reviewed-by: Robert Griesemer <gri@golang.org>

Prior to stack tracing, inlining could cause
dead pointers to be kept alive in some loops.
See #18336 and CL 31674.

The adjustment removed by this change preserved the inlining status quo
in the face of Node structure changes, to avoid creating new problems.
Now that stack tracing provides precision, these hacks can be removed.

Of course, our inlining code model is already hacky (#17566),
but at least now there will be fewer epicyclical hacks.

Newly inline-able functions in std cmd as a result of this change:

hash/adler32/adler32.go:65:6: can inline (*digest).UnmarshalBinary
hash/fnv/fnv.go:281:6: can inline (*sum32).UnmarshalBinary
hash/fnv/fnv.go:292:6: can inline (*sum32a).UnmarshalBinary
reflect/value.go:1298:6: can inline Value.OverflowComplex
compress/bzip2/bit_reader.go:25:6: can inline newBitReader
encoding/xml/xml.go:365:6: can inline (*Decoder).switchToReader
vendor/golang_org/x/crypto/cryptobyte/builder.go:77:6: can inline (*Builder).AddUint16
crypto/x509/x509.go:1851:58: can inline buildExtensions.func2.1.1
crypto/x509/x509.go:1871:58: can inline buildExtensions.func2.3.1
crypto/x509/x509.go:1883:58: can inline buildExtensions.func2.4.1
cmd/vet/internal/cfg/builder.go:463:6: can inline (*builder).labeledBlock
crypto/tls/handshake_messages.go:1450:6: can inline (*newSessionTicketMsg).marshal
crypto/tls/handshake_server.go:769:6: can inline (*serverHandshakeState).clientHelloInfo
crypto/tls/handshake_messages.go:1171:6: can inline (*nextProtoMsg).unmarshal
cmd/link/internal/amd64/obj.go:40:6: can inline Init
cmd/link/internal/ppc64/obj.go:40:6: can inline Init
net/http/httputil/persist.go:54:6: can inline NewServerConn
net/http/fcgi/child.go:83:6: can inline newResponse
cmd/compile/internal/ssa/poset.go:245:6: can inline (*poset).newnode

Change-Id: I19e8e383a6273849673d35189a9358870665f82f
Reviewed-on: https://go-review.googlesource.com/c/141117
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ilya Tocar <ilya.tocar@intel.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>

These marker comments are in every other zsyscall_*.go file generated by
mksyscall.pl. Also add them to the files generated by mksyscall_libc.pl
used for aix and solaris.

Change-Id: I7fd125df3549d83c658bbe7424861c76c024f2e5
Reviewed-on: https://go-review.googlesource.com/c/141037
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

This commit adds AIX operating system to net package for ppc64
architecture.

Updates: #25893

Change-Id: I46bbc7b03931019beb969443cb3f9a756956c66c
Reviewed-on: https://go-review.googlesource.com/c/138724
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

Do []byte(string) conversions more efficiently when the string
is a constant. Instead of calling stringtobyteslice, allocate
just the space we need and encode the initialization directly.

[]byte("foo") rewrites to the following pseudocode:

var s [3]byte // on heap or stack, depending on whether b escapes
s = *(*[3]byte)(&"foo"[0]) // initialize s from the string
b = s[:]

which generates this assembly:

	0x001d 00029 (tmp1.go:9)	LEAQ	type.[3]uint8(SB), AX
	0x0024 00036 (tmp1.go:9)	MOVQ	AX, (SP)
	0x0028 00040 (tmp1.go:9)	CALL	runtime.newobject(SB)
	0x002d 00045 (tmp1.go:9)	MOVQ	8(SP), AX
	0x0032 00050 (tmp1.go:9)	MOVBLZX	go.string."foo"+2(SB), CX
	0x0039 00057 (tmp1.go:9)	MOVWLZX	go.string."foo"(SB), DX
	0x0040 00064 (tmp1.go:9)	MOVW	DX, (AX)
	0x0043 00067 (tmp1.go:9)	MOVB	CL, 2(AX)
// Then the slice is b = {AX, 3, 3}

The generated code is still not optimal, as it still does load/store
from read-only memory instead of constant stores.  Next CL...

Update #26498
Fixes #10170

Change-Id: I4b990b19f9a308f60c8f4f148934acffefe0a5bd
Reviewed-on: https://go-review.googlesource.com/c/140698
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

This commit adds AIX operating system to mime package for ppc64
architecture.

Updates: #25893

Change-Id: I1b81a9204446c8c76ae24ea5c6fd33077c373ae4
Reviewed-on: https://go-review.googlesource.com/c/138723
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

This commit adds AIX operating system to crypto package for ppc64
architecture.

Updates: #25893

Change-Id: I20047ff2fef0051b8b235ec15b064c4a95c2b9c3
Reviewed-on: https://go-review.googlesource.com/c/138722
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

This commit adds AIX operating system to time package for ppc64
architecture.

Updates: #25893

Change-Id: I4fb6fb47eae7671bf4e22729d6d160f557083c44
Reviewed-on: https://go-review.googlesource.com/c/138721
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

This change makes use of a VSX instruction to generate the
float 0 value instead of generating a constant in memory and
loading it from there.

This uses 1 instruction instead of 2 and avoids a memory reference.
in the +0 case, uses 2 instructions in the -0 case but avoids
the memory reference.

Since this is done in the assembler for ppc64x, an update has
been made to the assembler test.

Change-Id: Ief7dddcb057bfb602f78215f6947664e8c841464
Reviewed-on: https://go-review.googlesource.com/c/139420Reviewed-by: Michael Munday <mike.munday@ibm.com>

This commit adds AIX operating system to syscall package for ppc64
architecture.
It also adds the file syscall_aix.go in the runtime package for
syscalls needed during fork and exec.

Updates: #25893

Change-Id: I301b1051b178a3efb7bbc39cdbd8e00b594d65ef
Reviewed-on: https://go-review.googlesource.com/c/138720
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

The previous ReverseProxy change, CL 137335, introduced a bug which could cause
a race and/or a crash.

This reliably crashed before:

$ go test -short -race -v -run=TestReverseProxyFlushInterval -count=20 net/http/httputil

The problem was a goroutine was running http.ResponseWriter.Flush
after the http.Handler's ServeHTTP completed. There was code to
prevent that (a deferred stop call) but the stop call didn't consider
the case where time.AfterFunc had already fired off a new goroutine
but that goroutine hadn't yet scheduled.

Change-Id: I06357908465a3b953efc33e63c70dec19a501adf
Reviewed-on: https://go-review.googlesource.com/c/140977
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Dmitri Shuralyov <dmitshur@golang.org>

If the test has already completed when a go routine with a panic
handler reports an error the location of the error call is lost.

Added logDepth to be able to log location of failure at different
depths down the stack.

Fixes #26720

Change-Id: I8b7789ddae757ef6f4bd315cb20356709f4fadec
Reviewed-on: https://go-review.googlesource.com/c/127596
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

AIX and Solaris both requires libc to make any syscalls and their
implementation is really similar.
Therefore, Solaris files reused by AIX have their name changed to *_libc.

exec_libc.go is also adapted to AIX.

Updates: #25893

Change-Id: I50d1d7b964831637013d5e64799187cd9565c42b
Reviewed-on: https://go-review.googlesource.com/c/138719
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

Fixes #28095

Change-Id: Id8668d52986c9805213e8847f49fe42dfde2e01a
Reviewed-on: https://go-review.googlesource.com/c/140797
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

Previously, erroneous usage would produce error messages like:

	FAIL: testdata/script/mod_tidy_replace.txt:4: usage: stdout [-count=N] 'pattern' file

where the “file” argument is not actually valid for the stdout command.

Change-Id: I74100960f4d25da122faa6c82620995a3fbfc75f
Reviewed-on: https://go-review.googlesource.com/c/140858
Run-TryBot: Bryan C. Mills <bcmills@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

The empty string is never a valid package path.
Passing an empty string to a function that expects a package path
indicates some missing validation step further up the call chain —
typically (and most easily) a missed error check.

Change-Id: I78a2403d95b473bacb0d40814cd9d477ecfd5351
Reviewed-on: https://go-review.googlesource.com/c/140857
Run-TryBot: Bryan C. Mills <bcmills@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

Major cleanup to structure the code more similarly to go/constant.

Passes "toolstash -cmp" on std cmd.

Change-Id: I3ec7a7a24e313f119b0da4095001aad02e317894
Reviewed-on: https://go-review.googlesource.com/c/139901
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>

Fixes #28044

Change-Id: I0052e078dd34dc3546204416bcc5a99e3146c535
Reviewed-on: https://go-review.googlesource.com/c/140317
Run-TryBot: Dmitri Shuralyov <dmitshur@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>

gosweepdone is another anachronism from the time when the sweeper was
implemented in C. Rename it to "isSweepDone" for the modern era.

Change-Id: I8472aa6f52478459c3f2edc8a4b2761e73c4c2dd
Reviewed-on: https://go-review.googlesource.com/c/138658
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

gosweepone just switches to the system stack and calls sweepone.
sweepone doesn't need to run on the system stack, so this is pretty
pointless.

Historically, this was necessary because the sweeper was written in C
and hence needed to run on the system stack. gosweepone was the
function that Go code (specifically, bgsweep) used to call into the C
sweeper implementation. This probably became unnecessary in 2014 with
CL golang.org/cl/167540043, which ported the sweeper to Go.

This CL changes all callers of gosweepone to call sweepone and
eliminates gosweepone.

Change-Id: I26b8ef0c7d060b4c0c5dedbb25ecfc936acc7269
Reviewed-on: https://go-review.googlesource.com/c/138657
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

For unclear reasons, cacheSpan and uncacheSpan compute the number of
elements in a span by dividing its size by the element size. This
number is simply available in the mspan structure, so just use it.

Change-Id: If2e5de6ecec39befd3324bf1da4a275ad000932f
Reviewed-on: https://go-review.googlesource.com/c/138656
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Lazy mcache flushing (golang.org/cl/134783) made it so that moving a
span from an mcache to an mcentral was sometimes responsible for
sweeping the span. However, it did a "preserving" sweep, which meant
it retained ownership, even if the sweeper swept all objects in the
span. As a result, we could put a completely unused span back in the
mcentral.

Fix this by first taking back ownership of the span into the mcentral
and moving it to the right mcentral list, and then doing a
non-preserving sweep. The non-preserving sweep will move the span to
the heap if it sweeps all objects.

Change-Id: I244b1893b44b8c00264f0928ac9239449775f617
Reviewed-on: https://go-review.googlesource.com/c/140597
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Michael Knyszek <mknyszek@google.com>

Lazy mcache flushing (golang.org/cl/134783) introduced a second value
for sweepgen that indicates a span has been swept. I missed adding
this case to a sanity check in sweepone, so it can now panic if it
finds a non-in-use spans that's been swept *and* put in an mcache.

Fix this by adding the second sweepgen case to this check.

Fixes #27997.

Change-Id: I568d9f2cc8923396ca897a37d154cd2c859c7bef
Reviewed-on: https://go-review.googlesource.com/c/140697
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

Since atomic.Or8 is now an intrinsic (and has been for some time),
markBits.setMarked is inlinable. Undo the manual inlining of it.

Change-Id: I8e37ccf0851ad1d3088d9c8ae0f6f0c439d7eb2d
Reviewed-on: https://go-review.googlesource.com/c/138659
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

freeSpan currently takes a mysterious "acct int32" argument. This is
really just a boolean and actually just needs to match the "large"
argument to alloc in order to balance out accounting.

To make this clearer, replace acct with a "large bool" argument that
must match the call to mheap.alloc.

Change-Id: Ibc81faefdf9f0583114e1953fcfb362e9c3c76de
Reviewed-on: https://go-review.googlesource.com/c/138655
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

* Rewrite the flushing code to not use a persistent goroutine, which
  also simplifies testing.
* Define the meaning of a negative flush interval. Its meaning doesn't
  change, but now it's locked in, and then we can use it to optimize
  the performance of the non-buffered case to avoid use of an AfterFunc.
* Support (internal-only) special casing of FlushInterval values per
  request/response.
* For now, treat Server-Sent Event responses as unbuffered. (or rather,
  immediately flushed from the buffer per-write)

Fixes #27816

Change-Id: Ie0f975c997daa3db539504137c741a96d7022665
Reviewed-on: https://go-review.googlesource.com/c/137335
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Dmitri Shuralyov <dmitshur@golang.org>

Change-Id: I098b3c627c2142affd4e800a2c1f37e00f3775c5
Reviewed-on: https://go-review.googlesource.com/c/140777Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

According to https://tools.ietf.org/html/rfc6962#section-3.3, the SCT
must be at least one byte long. The parsing code correctly checks for
this condition, but rarely the test does generate an empty SCT.

Change-Id: If36a34985b4470a5a9f96affc159195c04f6bfad
Reviewed-on: https://go-review.googlesource.com/c/129755Reviewed-by: Filippo Valsorda <filippo@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

BSFQ/BSRQ/BSFL/BSRL/SQRTSD have similar logic in amd64's assembly
generator. This CL combines them together while does not impact
generated amd64 code. The total size of
pkg/linux_amd64/cmd/compile/internal decreases about 1.8KB.

Change-Id: I5f3210c5178c20ac9108877c69f17234baf5b6b7
Reviewed-on: https://go-review.googlesource.com/c/140438
Run-TryBot: Ben Shi <powerman1st@163.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>

This CL implements indexed memory operands for the following instructions.
(ADD|SUB|MUL|AND|OR|XOR)Lload -> (ADD|SUB|MUL|AND|OR|XOR)Lloadidx4
(ADD|SUB|AND|OR|XOR)Lmodify -> (ADD|SUB|AND|OR|XOR)Lmodifyidx4
(ADD|AND|OR|XOR)Lconstmodify -> (ADD|AND|OR|XOR)Lconstmodifyidx4

1. The total size of pkg/linux_386/ decreases about 2.5KB, excluding
cmd/compile/ .

2. There is little regression in the go1 benchmark test, excluding noise.
name                     old time/op    new time/op    delta
BinaryTree17-4              3.25s ± 3%     3.25s ± 3%    ~     (p=0.218 n=40+40)
Fannkuch11-4                3.53s ± 1%     3.53s ± 1%    ~     (p=0.303 n=40+40)
FmtFprintfEmpty-4          44.9ns ± 3%    45.6ns ± 3%  +1.48%  (p=0.030 n=40+36)
FmtFprintfString-4         78.7ns ± 5%    80.1ns ± 7%    ~     (p=0.217 n=36+40)
FmtFprintfInt-4            90.2ns ± 6%    89.8ns ± 5%    ~     (p=0.659 n=40+38)
FmtFprintfIntInt-4          140ns ± 5%     141ns ± 5%  +1.00%  (p=0.027 n=40+40)
FmtFprintfPrefixedInt-4     185ns ± 3%     183ns ± 3%    ~     (p=0.104 n=40+40)
FmtFprintfFloat-4           411ns ± 4%     406ns ± 3%  -1.37%  (p=0.005 n=40+40)
FmtManyArgs-4               590ns ± 4%     598ns ± 4%  +1.35%  (p=0.008 n=40+40)
GobDecode-4                7.16ms ± 5%    7.10ms ± 5%    ~     (p=0.335 n=40+40)
GobEncode-4                6.85ms ± 7%    6.74ms ± 9%    ~     (p=0.058 n=38+40)
Gzip-4                      400ms ± 4%     399ms ± 2%  -0.34%  (p=0.003 n=40+33)
Gunzip-4                   41.4ms ± 3%    41.4ms ± 4%  -0.12%  (p=0.020 n=40+40)
HTTPClientServer-4         64.1µs ± 4%    63.5µs ± 2%  -1.07%  (p=0.000 n=39+37)
JSONEncode-4               15.9ms ± 2%    15.9ms ± 3%    ~     (p=0.103 n=40+40)
JSONDecode-4               62.2ms ± 4%    61.6ms ± 3%  -0.98%  (p=0.006 n=39+40)
Mandelbrot200-4            5.18ms ± 3%    5.14ms ± 4%    ~     (p=0.125 n=40+40)
GoParse-4                  3.29ms ± 2%    3.27ms ± 2%  -0.66%  (p=0.006 n=40+40)
RegexpMatchEasy0_32-4       103ns ± 4%     103ns ± 4%    ~     (p=0.632 n=40+40)
RegexpMatchEasy0_1K-4       830ns ± 3%     828ns ± 3%    ~     (p=0.563 n=40+40)
RegexpMatchEasy1_32-4       113ns ± 4%     113ns ± 4%    ~     (p=0.494 n=40+40)
RegexpMatchEasy1_1K-4      1.03µs ± 4%    1.03µs ± 4%    ~     (p=0.665 n=40+40)
RegexpMatchMedium_32-4      130ns ± 4%     129ns ± 3%    ~     (p=0.458 n=40+40)
RegexpMatchMedium_1K-4     39.4µs ± 3%    39.7µs ± 3%    ~     (p=0.825 n=40+40)
RegexpMatchHard_32-4       2.16µs ± 4%    2.15µs ± 4%    ~     (p=0.137 n=40+40)
RegexpMatchHard_1K-4       65.2µs ± 3%    65.4µs ± 4%    ~     (p=0.160 n=40+40)
Revcomp-4                   1.87s ± 2%     1.87s ± 1%  +0.17%  (p=0.019 n=33+33)
Template-4                 69.4ms ± 3%    69.8ms ± 3%  +0.60%  (p=0.009 n=40+40)
TimeParse-4                 437ns ± 4%     438ns ± 4%    ~     (p=0.234 n=40+40)
TimeFormat-4                408ns ± 3%     408ns ± 3%    ~     (p=0.904 n=40+40)
[Geo mean]                 65.7µs         65.6µs       -0.08%

name                     old speed      new speed      delta
GobDecode-4               107MB/s ± 5%   108MB/s ± 5%    ~     (p=0.336 n=40+40)
GobEncode-4               112MB/s ± 6%   114MB/s ± 9%  +1.95%  (p=0.036 n=37+40)
Gzip-4                   48.5MB/s ± 4%  48.6MB/s ± 2%  +0.28%  (p=0.003 n=40+33)
Gunzip-4                  469MB/s ± 4%   469MB/s ± 4%  +0.11%  (p=0.021 n=40+40)
JSONEncode-4              122MB/s ± 2%   122MB/s ± 3%    ~     (p=0.105 n=40+40)
JSONDecode-4             31.2MB/s ± 4%  31.5MB/s ± 4%  +0.99%  (p=0.007 n=39+40)
GoParse-4                17.6MB/s ± 2%  17.7MB/s ± 2%  +0.66%  (p=0.007 n=40+40)
RegexpMatchEasy0_32-4     310MB/s ± 4%   310MB/s ± 4%    ~     (p=0.384 n=40+40)
RegexpMatchEasy0_1K-4    1.23GB/s ± 3%  1.24GB/s ± 3%    ~     (p=0.186 n=40+40)
RegexpMatchEasy1_32-4     283MB/s ± 3%   281MB/s ± 4%    ~     (p=0.855 n=40+40)
RegexpMatchEasy1_1K-4    1.00GB/s ± 4%  1.00GB/s ± 4%    ~     (p=0.665 n=40+40)
RegexpMatchMedium_32-4   7.68MB/s ± 4%  7.73MB/s ± 3%    ~     (p=0.359 n=40+40)
RegexpMatchMedium_1K-4   26.0MB/s ± 3%  25.8MB/s ± 3%    ~     (p=0.825 n=40+40)
RegexpMatchHard_32-4     14.8MB/s ± 3%  14.9MB/s ± 4%    ~     (p=0.136 n=40+40)
RegexpMatchHard_1K-4     15.7MB/s ± 3%  15.7MB/s ± 4%    ~     (p=0.150 n=40+40)
Revcomp-4                 136MB/s ± 1%   136MB/s ± 1%  -0.09%  (p=0.028 n=32+33)
Template-4               28.0MB/s ± 3%  27.8MB/s ± 3%  -0.59%  (p=0.010 n=40+40)
[Geo mean]               82.1MB/s       82.3MB/s       +0.25%

Change-Id: Ifa387a251056678326d3508aa02753b70bf7e5d0
Reviewed-on: https://go-review.googlesource.com/c/140303
Run-TryBot: Ben Shi <powerman1st@163.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>

Change-Id: Ie5b2ef0087dbc7b8191de8c8b4190396631e3c7f
Reviewed-on: https://go-review.googlesource.com/c/137215
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

The commit 0e4c013b changed the syscall package so it uses the
asynchronous functions of Node.js's fs module.

This commit adapts the stubs of the fs module which are used when using
a browser instead of Node.js.

Fixes #28068.

Change-Id: Ic3a6a8aebb0db06402383bc2fea7642a4501e02c
Reviewed-on: https://go-review.googlesource.com/c/140537Reviewed-by: Agniva De Sarker <agniva.quicksilver@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

The spec used the term "conversion" somewhat indiscriminately for
explicit conversions that appear literally in the source, and implicit
conversions that are implied by the context of an expression.
Be clearer about it by defining the terms.

Also, state that integer to string conversions of the form string(x)
are never implicit. This clarifies situations where implicit conversions
might require an integer to change to a string (but don't and never have
done so). See line 3948.

Fixes #26313.

Change-Id: I8939466df6b5950933ae7c987662ef9f88827fda
Reviewed-on: https://go-review.googlesource.com/c/139099Reviewed-by: Rob Pike <r@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

Similarly to CL 138676, skip TestUnixConnLocalWindows on windows/arm.

Fixes #28061

Change-Id: I2270d2f9d268e85ea567be0c0c37c48e4d482282
Reviewed-on: https://go-review.googlesource.com/c/140397
Run-TryBot: Alex Brainman <alex.brainman@gmail.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

Change-Id: I94cebca86706e072fbe3be782d3edbe0e22b9432
GitHub-Last-Rev: 8e15a40545704fb21b41a8768079f2da19341ef3
GitHub-Pull-Request: golang/go#28067
Reviewed-on: https://go-review.googlesource.com/c/140437
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>