(x<<1 | x>>31).

Fixes #5084.

On the SHA3 benchmark proposals at
https://golang.org/cl/7760044/

benchmark                       old ns/op    new ns/op    delta
BenchmarkPermutationFunction         1288         1191   -7.53%
BenchmarkSingleByteWrite             5795         5811   +0.28%
BenchmarkBlockWrite512                178          179   +0.56%
BenchmarkBlockWrite384                230          233   +1.30%
BenchmarkBlockWrite256                282          286   +1.42%
BenchmarkBlockWrite224                301          306   +1.66%
BenchmarkBulkHashSHA3_512          326885       304548   -6.83%
BenchmarkBulkHashSHA3_384          234839       220074   -6.29%
BenchmarkBulkHashSHA3_256          186969       175790   -5.98%
BenchmarkBulkHashSHA3_224          178133       167489   -5.98%

For a function like

func g() {
        x = a[3]<<20 | a[3]>>12
}

the asm goes from

0006 (main.go:10) TEXT    g+0(SB),$0-0
0007 (main.go:10) MOVL    a+12(SB),BP
0008 (main.go:10) LOCALS  ,$0
0009 (main.go:11) MOVL    BP,BX
0010 (main.go:11) SHLL    $20,BX
0011 (main.go:11) SHRL    $12,BP
0012 (main.go:11) ORL     BP,BX
0013 (main.go:11) MOVL    BX,x+0(SB)
0014 (main.go:12) RET     ,

to

0006 (main.go:10) TEXT    g+0(SB),$0-0
0007 (main.go:10) LOCALS  ,$0
0008 (main.go:11) MOVL    a+12(SB),BX
0009 (main.go:11) ROLL    $20,BX
0010 (main.go:11) MOVL    BX,x+0(SB)
0011 (main.go:12) RET     ,

R=rsc, iant, remyoudompheng
CC=golang-dev, jcb
https://golang.org/cl/7944043

Mention support for NetBSD, OpenBSD, and cgo for linux/arm.

R=golang-dev, dvyukov, r, minux.ma, adg, bradfitz, adg
CC=golang-dev
https://golang.org/cl/8152043

Doing grow work on reads is not multithreaded safe.
Changed code to do grow work only on inserts & deletes.

This is a short-term fix, eventually we'll want to do
grow work in parallel to recover the space of the old
table.

Fixes #5120.

R=bradfitz, khr
CC=golang-dev
https://golang.org/cl/8242043

Fixes #5176.

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/8118046

The text is printed only if the test fails or -test.v is set.
Document this behavior in the testing package and 'go help test'.
Also put a 'go install' into mkdoc.sh so I don't get tricked by the
process of updating the documentation ever again.

Fixes #5174.

R=golang-dev, dsymonds
CC=golang-dev
https://golang.org/cl/8118047

Fixes #5024.

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/8222045

Fixes #4730.

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/8229043

use MOVW.NE instead of BEQ and MOVW.

R=golang-dev, dave, rsc, daniel.morsing
CC=golang-dev
https://golang.org/cl/7718043

Eliminates a format consistency warning.

R=gloang-dev, r
CC=golang-dev
https://golang.org/cl/8217043

Permits specifying the linker to use, and trailing flags to
pass to that linker, when linking in external mode.  External
mode linking is used when building a package that uses cgo, as
described in the cgo docs.

Also document -linkmode and -tmpdir.

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/8225043

Reusing it when multiple comparisons occurred in the same
function call led to bad overwriting.

Fixes #5162.

R=golang-dev, daniel.morsing
CC=golang-dev
https://golang.org/cl/8174047

Currently crashes, so disabled.

Update #5179

R=golang-dev, khr
CC=golang-dev
https://golang.org/cl/8222044

If a package was listed as a dependency from multiple places, it
could have been cleaned repeatedly.

R=golang-dev, dave, rsc, seed, bradfitz
CC=golang-dev, minux.ma
https://golang.org/cl/7482043

Fixes #5149.

R=golang-dev, dave, minux.ma
CC=golang-dev
https://golang.org/cl/8136043

<stdint.h> does not seem to be needed.

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/8178044

Closes the API documentation gap between platforms.

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/8063044

Closes the API documentation gap between platforms.
Also makes the code textual representation same between platforms.

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/8148043

Closes the API documentation gap between platforms.
Also makes the code textual representation same between platforms.

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/8147043

Closes the API documentation gap between platforms.

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/8143044

Since we can't properly handle anything except 100, treat all
1xx informational responses as sketchy and don't reuse the
connection for future requests.

The only other 1xx response code currently in use in the wild
is WebSockets' use of "101 Switching Protocols", but our
code.google.com/p/go.net/websockets doesn't use Client or
Transport: it uses ReadResponse directly, so is unaffected by
this CL.  (and its tests still pass)

So this CL is entirely just future-proofing paranoia.
Also: the Internet is weird.

Update #2184
Update #3665

R=golang-dev, dsymonds
CC=golang-dev
https://golang.org/cl/8208043

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/8201043

Whoops. I'm surprised it even worked before. (Need two pipes,
not one.)

Also, remove the whole pipe registration business, since it
wasn't even required in the previous version. (I'd later fixed
it at the end of send100Response, but forgot to delete it)

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/8191044

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/8198043

R=golang-dev, minux.ma
CC=golang-dev
https://golang.org/cl/8187045

Some packages, like popwin.el, change display behaviour based on
the buffer's mode, so we should enable compilation-mode before
displaying the buffer.

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/8155043

src/cmd/gc/closure.c:133 param declared and not used: nowrap
src/cmd/gc/const.c:1139 set and not used: t1
src/cmd/ld/data.c:652 format mismatch #llx INT, arg 7
src/cmd/ld/data.c:652 format mismatch #llx INT, arg 8
src/cmd/ld/data.c:1230 set and not used: datsize

R=dave, golang-dev, lucio.dere, remyoudompheng, bradfitz
CC=golang-dev
https://golang.org/cl/8182043

src/cmd/6g/peep.c:471 set and not used: r
src/cmd/6g/peep.c:560 overspecified class: regconsttyp GLOBL STATIC
src/cmd/6g/peep.c:761 more arguments than format IND STRUCT Prog
src/cmd/6g/reg.c:185 set and not used: r1
src/cmd/6g/reg.c:786 format mismatch d VLONG, arg 3
src/cmd/6g/reg.c:1064 format mismatch d VLONG, arg 5

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/8197044

R=golang-dev, bradfitz, minux.ma
CC=golang-dev
https://golang.org/cl/8193043

Add missing getgoextlinkenabled(void) declaration
in Plan 9 libc.h. This function was added as part
of CL #8183043.

R=golang-dev, minux.ma
CC=golang-dev
https://golang.org/cl/8191043

R=golang-dev, minux
CC=golang-dev
https://golang.org/cl/8174045

This CL ensures we use the correct socket options for
passive and active open sockets.

For the passive open sockets created by Listen functions,
additional SO_REUSEADDR, SO_REUSEPORT options are required
for the quick service restart and/or multicasting.

For the active open sockets created by Dial functions, no
additional options are required.

R=golang-dev, dave, bradfitz, rsc
CC=golang-dev
https://golang.org/cl/7795050

R=dsymonds, mikioh.mikioh
CC=golang-dev
https://golang.org/cl/8094047

"There are only two hard problems in computer science:
cache invalidation, naming things, and off-by-one errors."

The HTTP server code already strips Expect: 100-continue on
requests, so httputil.ReverseProxy should be unaffected, but
some servers send unsolicited HTTP/1.1 100 Continue responses,
so we need to skip over them if they're seen to avoid getting
off-by-one on Transport requests/responses.

This does change the behavior of people who were using Client
or Transport directly and explicitly setting "Expect: 100-continue"
themselves, but it didn't work before anyway. Now instead of the
user code seeing a 100 response and then things blowing up, now
it basically works, except the Transport will still blast away
the full request body immediately.  That's the part that needs
to be finished to close this issue.

This is the safe quick fix.

Update #3665

R=golang-dev, dsymonds, dave, jgrahamc
CC=golang-dev
https://golang.org/cl/8166045

Change build system to set GO_EXTLINK_ENABLED=0 by default for
OS X 10.6, since the system linker has a bug and can not
handle the object files generated by 6l.

Fixes #5130.

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/8183043

This benchmark verifies that CL #8173043 reduces time spent
sliding the Buffer's contents.

Results without and with CL #8173043 applied:
benchmark                        old ns/op    new ns/op    delta
BenchmarkBufferFullSmallReads       755336       175054  -76.82%

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/8174043

Generated by addca.

R=gobot
CC=golang-dev
https://golang.org/cl/8176043

Do a little reformatting too.
Fixes #5152.

R=golang-dev, bradfitz, gri
CC=golang-dev
https://golang.org/cl/8157044

For the future.

Update #5147

R=khr, r
CC=golang-dev
https://golang.org/cl/8165044

benchmark                           old ns/op    new ns/op    delta
BenchmarkBufferNotEmptyWriteRead       848416       819983   -3.35%

Update #5154

R=golang-dev, gri, robryk
CC=golang-dev
https://golang.org/cl/8173043

Also added a new benchmark from the same test:

benchmark                           old ns/op    new ns/op    delta
BenchmarkBufferNotEmptyWriteRead      2643698       709189  -73.17%

Fixes #5154

R=golang-dev, r, gri
CC=golang-dev
https://golang.org/cl/8164043