With dup3, we can avoid an extra system call on some machines
while holding syscall.ForkLock. Currently we have to
syscall.Dup + syscall.CloseOnExec.

On machines with Linux and a new enough kernel, this can just
be dup3.

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/12170045

Fixes #5953

R=golang-dev, dsymonds
CC=golang-dev
https://golang.org/cl/12117043

More functions needs to be marked as no stack split.

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/11963044

(Replacement for CL 11884043.)

1) Explain a[i] and a[i:j] where a is of type *A as
   shortcut for (*a)[i] and (*a)[i:j], respectively.

2) Together with 1), because len() of nil slices is
   well defined, there's no need to special case nil
   operands anymore.

3) The result of indexing or slicing a constant string
   is always a non-constant byte or string value.

4) The result of slicing an untyped string is a value
   of type string.

5) If the operand of a valid slice a[i:j] is nil (i, j
   must be 0 for it to be valid - this already follows
   from the in-range rules), the result is a nil slice.

Fixes #4913.
Fixes #5951.

R=r, rsc, iant, ken
CC=golang-dev
https://golang.org/cl/12198043

These are moved to code.google.com/p/go.tools/cmd/godoc.

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/12220043

Mark the 386 one too for consistency,
although most of that code is no longer used.

TBR=dvyukov
CC=golang-dev
https://golang.org/cl/12227043

Preemption during the software floating point code
could cause m (R9) to change, so that when the
original registers were restored at the end of the
floating point handler, the changed and correct m
would be replaced by the old and incorrect m.

TBR=dvyukov
CC=golang-dev
https://golang.org/cl/11883045

R=golang-dev, dave, dsymonds
CC=golang-dev
https://golang.org/cl/12225043

See also https://golang.org/cl/12180043/

R=adg
CC=golang-dev
https://golang.org/cl/12213043

R=golang-dev
CC=golang-dev
https://golang.org/cl/12222043

The godoc command now lives at code.google.com/p/go.tools/cmd/godoc.

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/12206044

Also suggest "go get" if godoc not found when running "go doc".

R=golang-dev, r, rsc
CC=golang-dev
https://golang.org/cl/12214043

Fixes #5998.

R=golang-dev, khr
CC=golang-dev
https://golang.org/cl/12149043

R=golang-dev, dsymonds
CC=golang-dev
https://golang.org/cl/12208043

Breaks all ELF builds.

««« original CL description
       cmd/ld: report pclntab, funcdata sizes in 6l -v output
       Also move chatty recent additions to -v -v.

       For what it's worth:

       $ go build -o /dev/null -ldflags -v cmd/godoc
       ...
        0.73 pclntab=1259976 bytes, funcdata total 79788 bytes
       ...
       $

R=ken2
CC=cshapiro, golang-dev
https://golang.org/cl/12193043
»»»

R=rsc
CC=golang-dev
https://golang.org/cl/12202043

Operations on int64 are very stack consuming with 5c.
Fixes netbsd/arm build.

Before: TEXT    runtime.timediv+0(SB),7,$52-16
After:  TEXT    runtime.timediv+0(SB),7,$44-16

The stack usage is unchanged on 386:
        TEXT    runtime.timediv+0(SB),7,$8-16

R=golang-dev, dvyukov, bradfitz
CC=golang-dev
https://golang.org/cl/12182044

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/12174043

1. They are FIFOs.
2. They are safe for concurrent access.

Fixes #5911.

R=golang-dev, dvyukov, adg
CC=golang-dev
https://golang.org/cl/11549043

Fixes #4940.

R=golang-dev, bradfitz, gri
CC=golang-dev
https://golang.org/cl/12021044

CL submitted prematurely by mistake.

««« original CL description
spec: clarify index and selector expressions

1) Explain a[i] and a[i:j] where a is of type *A as
   shortcut for (*a)[i] and (*a)[i:j], respectively.

2) Together with 1), because len() of nil slices is
   well defined, there's no need to special case nil
   operands anymore.

3) The result of indexing or slicing a constant string
   is always a non-constant byte or string value.

4) The result of slicing an untyped string is a value
   of type string.

5) If the operand of a valid slice a[i:j] is nil (i, j
   must be 0 for it to be valid - this already follows
   from the in-range rules), the result is a nil slice.

Fixes #4913.
Fixes #5951.

R=rsc, r, iant, ken
CC=golang-dev
https://golang.org/cl/11884043
»»»

R=r
CC=golang-dev
https://golang.org/cl/12170046

1) Explain a[i] and a[i:j] where a is of type *A as
   shortcut for (*a)[i] and (*a)[i:j], respectively.

2) Together with 1), because len() of nil slices is
   well defined, there's no need to special case nil
   operands anymore.

3) The result of indexing or slicing a constant string
   is always a non-constant byte or string value.

4) The result of slicing an untyped string is a value
   of type string.

5) If the operand of a valid slice a[i:j] is nil (i, j
   must be 0 for it to be valid - this already follows
   from the in-range rules), the result is a nil slice.

Fixes #4913.
Fixes #5951.

R=rsc, r, iant, ken
CC=golang-dev
https://golang.org/cl/11884043

This patch introduces specialized functions for initial
and final permutations, and precomputes the output of the
third permutation on the S-box elements.

benchmark           old ns/op    new ns/op    delta
BenchmarkEncrypt         3581         1226  -65.76%
BenchmarkDecrypt         3590         1224  -65.91%

benchmark            old MB/s     new MB/s  speedup
BenchmarkEncrypt         2.23         6.52    2.92x
BenchmarkDecrypt         2.23         6.53    2.93x

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/12072045

       Also move chatty recent additions to -v -v.

       For what it's worth:

       $ go build -o /dev/null -ldflags -v cmd/godoc
       ...
	0.73 pclntab=1259976 bytes, funcdata total 79788 bytes
       ...
       $

R=ken2
CC=cshapiro, golang-dev
https://golang.org/cl/12193043

Update #5139.
Double wakeup on Note was reported several times,
but no reliable reproducer.
There also was a strange report about weird value of epoll fd.
Maybe it's corruption of global data...

R=golang-dev, bradfitz
CC=golang-dev
https://golang.org/cl/12182043

Sysmon thread parks if no goroutines are running (runtime.sched.npidle ==
runtime.gomaxprocs).
Currently it's unparked when a goroutine enters syscall, it was enough
to retake P's from blocking syscalls.
But it's not enough for reliable goroutine preemption. We need to ensure that
sysmon runs if any goroutines are running.

R=rsc
CC=golang-dev
https://golang.org/cl/12176043

Submitted with some unrelated changes that were not intended to go in.

««« original CL description
runtime: do not park sysmon thread if any goroutines are running
Sysmon thread parks if no goroutines are running (runtime.sched.npidle == runtime.gomaxprocs).
Currently it's unparked when a goroutine enters syscall, it was enough
to retake P's from blocking syscalls.
But it's not enough for reliable goroutine preemption. We need to ensure that
sysmon runs if any goroutines are running.

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/12167043
»»»

R=rsc
CC=golang-dev
https://golang.org/cl/12171044

This is required to properly unwind reflect.methodValueCall/makeFuncStub.
Fixes #5954.
Stats for 'go install std':
61849 total INSTCALL
24655 currently have ArgSize metadata
27278 have ArgSize metadata with this change
godoc size before: 11351888, after: 11364288

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/12163043

Sysmon thread parks if no goroutines are running (runtime.sched.npidle == runtime.gomaxprocs).
Currently it's unparked when a goroutine enters syscall, it was enough
to retake P's from blocking syscalls.
But it's not enough for reliable goroutine preemption. We need to ensure that
sysmon runs if any goroutines are running.

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/12167043

I don't know why the memstats code is flaky.

TBR=bradfitz
CC=golang-dev
https://golang.org/cl/12160043

Fixes #5668.

R=golang-dev, rsc, r
CC=golang-dev
https://golang.org/cl/12001056

Fixes #5730.

R=dsymonds, r, kamil.kisiel
CC=golang-dev
https://golang.org/cl/11998044

Adds layout cases with seconds for stdISO8601 and stdNumTZ with and without colons. Update time.Format to append seconds for those cases.

Fixes #4934.

R=golang-dev, r, bradfitz
CC=golang-dev
https://golang.org/cl/8132044

Generated by addca.

R=gobot
CC=golang-dev
https://golang.org/cl/12146043

This means that printing a Node will produce output that can be used as valid input.
It won't be exactly the same - some spacing may be different - but it will mean the same.

Fixes #4593.

R=golang-dev, dsymonds
CC=golang-dev
https://golang.org/cl/12006047

When scanning input and "white space" is permitted, a carriage return
followed immediately by a newline (\r\n) is treated exactly the same
as a plain newline (\n). I hope this makes it work better on Windows.

We do it everywhere, not just on Windows, since why not?

Fixes #5391.

R=golang-dev, dsymonds
CC=golang-dev
https://golang.org/cl/12142043

When comparing strings, check these (in order):
- length mismatch => not equal
- string pointer equal => equal
- if length is short:
  - memeq on body
- if length is long:
  - compare first&last few bytes, if different => not equal
  - save entry as a possible match
  - after checking every entry, if there is only one possible
    match, use memeq on that entry.  Otherwise, fallback to hash.

benchmark                 old ns/op    new ns/op    delta
BenchmarkSameLengthMap           43            4  -89.77%

Fixes #5194.
Update #3885.

R=golang-dev, bradfitz, khr, rsc
CC=golang-dev
https://golang.org/cl/12128044

The prefix was not uniformly applied and is probably better left off anyway.

Fixes #4944.

R=golang-dev, dsymonds
CC=golang-dev
https://golang.org/cl/12140043

Fixes #5730.

R=golang-dev, dsymonds
CC=golang-dev
https://golang.org/cl/12141043

R=golang-dev, dave
CC=golang-dev
https://golang.org/cl/12090043

This is what I get for being talked into a test.

TBR=bradfitz
CC=golang-dev
https://golang.org/cl/12045044