With this change the compiler emits a bitmap for each function
covering its stack frame arguments area.  If an argument word
is known to contain a pointer, a bit is set.  The garbage
collector reads this information when scanning the stack by
frames and uses it to ignores locations known to not contain a
pointer.

R=golang-dev, bradfitz, daniel.morsing, dvyukov, khr, khr, iant, cshapiro
CC=golang-dev
https://golang.org/cl/9223046

This depends on: 9791044: runtime: allocate page table lazily
Once page table is moved out of heap, the heap becomes small.
This removes unnecessary dereferences during heap access.
No logical changes.

R=golang-dev, khr
CC=golang-dev
https://golang.org/cl/9802043

This removes the 256MB memory allocation at startup,
which conflicts with ulimit.
Also will allow to eliminate an unnecessary memory dereference in GC,
because the page table is usually mapped at known address.
Update #5049.
Update #5236.

R=golang-dev, khr, r, khr, rsc
CC=golang-dev
https://golang.org/cl/9791044

we need it for GC anyway.

R=golang-dev, khr, dave, khr
CC=golang-dev
https://golang.org/cl/9728044

Currently the test closes random files descriptors,
which leads to hang (in particular if netpoll fd is closed).
Try to open only fd 3, since the parent process expects it to be fd 3 anyway.
Fixes #5571.

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/9778048

The 'n' variable is used during rescan initiation in GC_END case,
but it's overwritten with chan capacity in GC_CHAN case.
As the result rescan is done with the wrong object size.
Fixes #5554.

R=golang-dev, khr
CC=golang-dev
https://golang.org/cl/9831043

also don't clobber R9 if it is about to crash.

In response to https://golang.org/cl/9251043/#msg2.

R=golang-dev, khr, khr, dave
CC=golang-dev
https://golang.org/cl/9778046

multiple failures on amd64

««« original CL description
runtime: introduce helper persistentalloc() function
It is a caching wrapper around SysAlloc() that can allocate small chunks.
Use it for symtab allocations. Reduces number of symtab walks from 4 to 3
(reduces buildfuncs time from 10ms to 7.5ms on a large binary,
reduces initial heap size by 680K on the same binary).
Also can be used for type info allocation, itab allocation.
There are also several places in GC where we do the same thing,
they can be changed to use persistentalloc().
Also can be used in FixAlloc, because each instance of FixAlloc allocates
in 128K regions, which is too eager.

R=golang-dev, daniel.morsing, khr
CC=golang-dev
https://golang.org/cl/9805043
»»»

R=golang-dev
CC=golang-dev
https://golang.org/cl/9822043

benchmark                    old ns/op    new ns/op    delta
BenchmarkMalloc8                    68           62   -8.63%
BenchmarkMalloc16                   75           69   -7.94%
BenchmarkMallocTypeInfo8           102           98   -3.73%
BenchmarkMallocTypeInfo16          108          103   -4.63%

R=golang-dev, dave, khr
CC=golang-dev
https://golang.org/cl/9790043

It is a caching wrapper around SysAlloc() that can allocate small chunks.
Use it for symtab allocations. Reduces number of symtab walks from 4 to 3
(reduces buildfuncs time from 10ms to 7.5ms on a large binary,
reduces initial heap size by 680K on the same binary).
Also can be used for type info allocation, itab allocation.
There are also several places in GC where we do the same thing,
they can be changed to use persistentalloc().
Also can be used in FixAlloc, because each instance of FixAlloc allocates
in 128K regions, which is too eager.

R=golang-dev, daniel.morsing, khr
CC=golang-dev
https://golang.org/cl/9805043

R=golang-dev, minux.ma
CC=golang-dev
https://golang.org/cl/9808043

In preparation for CL 9249043 (already submitted).

Fixes #5553.

R=golang-dev, iant, capnm9, dave
CC=golang-dev
https://golang.org/cl/9251043

R=golang-dev, dsymonds
CC=golang-dev
https://golang.org/cl/9648044

Variables in data sections of 32-bit executables interfere with
garbage collector's ability to free objects and/or unnecessarily
slow down the garbage collector.

This changeset moves some static variables to .noptr sections.
'files' in symtab.c is now allocated dynamically.

R=golang-dev, dvyukov, minux.ma
CC=golang-dev
https://golang.org/cl/9786044

This fixes two intra-page "type assertion" links that were broken in
different ways.

R=golang-dev, dsymonds
CC=golang-dev
https://golang.org/cl/9797043

Generated by addca.

R=gobot
CC=golang-dev
https://golang.org/cl/9797044

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/9665046

R=golang-dev, iant
CC=golang-dev
https://golang.org/cl/9574043

This text is added to doc.go:

        Explicit argument indexes:

        In Printf, Sprintf, and Fprintf, the default behavior is for each
        formatting verb to format successive arguments passed in the call.
        However, the notation [n] immediately before the verb indicates that the
        nth one-indexed argument is to be formatted instead. The same notation
        before a '*' for a width or precision selects the argument index holding
        the value. After processing a bracketed expression [n], arguments n+1,
        n+2, etc. will be processed unless otherwise directed.

        For example,
                fmt.Sprintf("%[2]d %[1]d\n", 11, 22)
        will yield "22, 11", while
                fmt.Sprintf("%[3]*[2].*[1]f", 12.0, 2, 6),
        equivalent to
                fmt.Sprintf("%6.2f", 12.0),
        will yield " 12.00". Because an explicit index affects subsequent verbs,
        this notation can be used to print the same values multiple times
        by resetting the index for the first argument to be repeated:
                fmt.Sprintf("%d %d %#[1]x %#x", 16, 17)
        will yield "16 17 0x10 0x11".

The notation chosen differs from that in C, but I believe it's easier to read
and to remember (we're indexing the arguments), and compatibility with
C's printf was never a strong goal anyway.

While we're here, change the word "field" to "arg" or "argument" in the
code; it was being misused and was confusing.

R=rsc, bradfitz, rogpeppe, minux.ma, peter.armitage
CC=golang-dev
https://golang.org/cl/9680043

Set $status as null to prevent rc from exiting
on the last --no-banner argument checking when
used with rc -e. It allows all.rc to not exit
before executing run.rc

R=golang-dev, lucio.dere, rsc
CC=golang-dev
https://golang.org/cl/9611045

This is a file of hints, not a file of polished text.
Let's not try to do polished text until we start the
release process.

R=golang-dev, gri
CC=golang-dev
https://golang.org/cl/9750043

crypto/x509 has ended up with a variety of error formats. This change makes them all start with "x509: ".

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/9736043

It doesn't work, it's not portable, it's not part of the released
binaries, and a better tool is due.

Fixes #1319.
Fixes #4621.

R=golang-dev, bradfitz, dave, rsc
CC=golang-dev
https://golang.org/cl/9681044

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/9713044

According to X.690, only 0 and 255 are allowed as values
for encoded booleans. Also added some test for parsing
booleans

R=golang-dev, agl, r
CC=golang-dev
https://golang.org/cl/9692043

Generated by addca.

R=gobot
CC=golang-dev
https://golang.org/cl/9734043

The problem was that server handlers block on done<-,
the goroutine that reads from done blocks on count<-,
and the main goroutine that is supposed to read from count
waits for server handlers to exit.
Fixes #5547.

R=golang-dev, dave, bradfitz
CC=golang-dev
https://golang.org/cl/9722043

R=golang-dev, minux.ma, capnm9
CC=golang-dev
https://golang.org/cl/9717043

Fixes build.

R=golang-dev
CC=golang-dev
https://golang.org/cl/9667047

Fixes #5548.

R=golang-dev, minux.ma
CC=golang-dev
https://golang.org/cl/9643044

R=golang-dev, dsymonds
CC=golang-dev
https://golang.org/cl/9656045

benchmark                old ns/op    new ns/op    delta
BenchmarkMapIter               191          190   -0.52%
BenchmarkMapIterEmpty           22            4  -78.96%

R=golang-dev, minux.ma, dvyukov, iant, khr
CC=golang-dev
https://golang.org/cl/9637043

Generated by addca.

R=gobot
CC=golang-dev
https://golang.org/cl/9669044

R=golang-dev, dsymonds
CC=golang-dev
https://golang.org/cl/9695045

Operations like gofmt and go-remove-unused-imports delete entire
lines of text. Previously this put them on the kill-ring,
negatively affecting user experience.

R=adonovan
CC=gobot, golang-dev
https://golang.org/cl/9605043

This only affects calls where both ReaderFrom and WriterTo are implemented. WriterTo can issue one large write, while ReaderFrom must Read until EOF, potentially reallocating when out of memory. With one large Write, the Writer only needs to allocate once.

This also helps in ioutil.Discard since we can avoid copying memory when the Reader implements WriterTo.

R=golang-dev, dsymonds, remyoudompheng, bradfitz
CC=golang-dev, minux.ma
https://golang.org/cl/9462044

This change contains an implementation of the RSASSA-PSS signature
algorithm described in RFC 3447.

R=agl, agl
CC=gobot, golang-dev, r
https://golang.org/cl/9438043

This CL adds missing IPv6 socket options which are required
to control IPv6 as described in RFC 3493, RFC 3542.

Update #5538

R=golang-dev, dave, iant
CC=golang-dev
https://golang.org/cl/9373046

Fixes #5042.

R=golang-dev, adg, rsc
CC=golang-dev
https://golang.org/cl/7786047

R=adg, bradfitz, r
CC=golang-dev
https://golang.org/cl/9626045