To reduce delta for the upcoming liblink CL.
Just code movement, no semantic changes.

LGTM=rsc
R=rsc, iant
CC=golang-codereviews
https://golang.org/cl/124830043

LGTM=rsc
R=rsc, iant
CC=golang-codereviews
https://golang.org/cl/117670045

After CL 117670045, cmd/dist will expect to have a cmd/9g directory.

LGTM=rsc, dave
R=rsc, iant, dave
CC=golang-codereviews
https://golang.org/cl/126780043

No modifications other than adding copyright header to each file, and
concatenating several cmd/9l files together to form the liblink files.

LGTM=rsc
R=rsc, iant
CC=golang-codereviews
https://golang.org/cl/123840043

LGTM=rsc
R=rsc, iant
CC=golang-codereviews
https://golang.org/cl/125760043

LGTM=minux
R=minux
CC=golang-codereviews
https://golang.org/cl/124820043

Causes server 500 error, so don't do it.

TBR=minux
CC=golang-codereviews
https://golang.org/cl/125770043

hg insists that we not list explicit files for a merge.

for benefit of other tools reading logs, include branch prefix
at start of every commit message.

LGTM=minux
R=minux
CC=golang-codereviews
https://golang.org/cl/124780044

1) The arrayindexof lookup function is O(n). Replace with O(1) lookups.

2) The checkptxt function is O(n²) and is purely for debugging.
Only run when the debugging flags are turned on.

3) Iterating over sparse bitmaps can be done faster word by word.
Introduce and use bvnext for that.

Run times before and after, on my 2.5 GHz Core i5 MacBook Pro.

x.go       9.48  0.84  issue 8259

x100.go    0.01  0.01  issue 8354
x1000.go   0.10  0.10
x2000.go   0.62  0.19
x3000.go   1.33  0.34
x4000.go   2.29  0.49
x5000.go   3.89  0.67
x6000.go   5.00  0.90
x7000.go   6.70  1.13
x8000.go   9.44  1.38
x9000.go  11.23  1.87
x10000.go 13.78  2.09

Fixes #8259.
Fixes #8354.

LGTM=iant, r
R=golang-codereviews, iant, r
CC=golang-codereviews
https://golang.org/cl/125720043

LGTM=minux
R=minux
CC=golang-codereviews
https://golang.org/cl/124810043

LGTM=minux
R=minux
CC=golang-codereviews
https://golang.org/cl/118690043

LGTM=minux
R=minux
CC=golang-codereviews
https://golang.org/cl/124800043

LGTM=minux
R=minux
CC=golang-codereviews
https://golang.org/cl/120690043

The linker currently produces the DWARF 3 DW_TAG_unspecified_type tag, however the Reader in debug/dwarf will panic whenever that tag is encountered.

Fixes #8437.

LGTM=rsc
R=golang-codereviews, bradfitz, iant, rsc
CC=golang-codereviews
https://golang.org/cl/117280043

Generated by a+c.

R=gobot
CC=golang-codereviews
https://golang.org/cl/125750043

LGTM=dave, minux, aram
R=minux, dave, bradfitz, aram
CC=golang-codereviews
https://golang.org/cl/119470043

This is an experiment. See mail on golang-dev
(subject: "an experiment: development branches").

LGTM=minux
R=minux
CC=golang-codereviews
https://golang.org/cl/117660043

It can happen legitimately if a profiling signal arrives at just the wrong moment.
It's harmless.

Fixes #8153.

LGTM=minux
R=golang-codereviews, minux
CC=golang-codereviews, iant, r
https://golang.org/cl/118670043

Revised version of https://golang.org/cl/81260045/

LGTM=agl
R=golang-codereviews, gobot, agl, ox
CC=golang-codereviews
https://golang.org/cl/107400043

Fixes #8478.

LGTM=iant
R=iant
CC=golang-codereviews
https://golang.org/cl/122150043

Left over from cl/119490044.

LGTM=bradfitz
R=rsc, bradfitz
CC=golang-codereviews
https://golang.org/cl/125730043

Full spans can't be passed to UncacheSpan since we get rid of free.

LGTM=rsc
R=golang-codereviews
CC=golang-codereviews, khr, rsc
https://golang.org/cl/119490044

Since CL 115060044, mkanames declares an empty
array in anames8.c and anames6.c, which is not
valid for the Plan 9 compiler.

char* cnames8[] = {
};

This change makes mkanames not declaring the
cnames array when no C_ constants are found.

LGTM=iant
R=minux, iant
CC=golang-codereviews
https://golang.org/cl/117680043

LGTM=dvyukov
R=golang-codereviews, dvyukov
CC=golang-codereviews
https://golang.org/cl/117670043

Broke freebsd/amd64 due to exposure of a latent bug.

««« original CL description
cmd/ld: fix operator precedence

LGTM=rsc
R=rsc, iant
CC=golang-codereviews
https://golang.org/cl/114420043
»»»

TBR=dfc
R=dave
CC=golang-codereviews
https://golang.org/cl/120630043

LGTM=rsc
R=golang-codereviews, gobot, rsc
CC=golang-codereviews
https://golang.org/cl/118480046

The helps certain diagnostics and also removed duplicated enums as a side effect.

LGTM=dave, rsc
R=rsc, dave
CC=golang-codereviews
https://golang.org/cl/115060044

LGTM=rsc
R=rsc, iant
CC=golang-codereviews
https://golang.org/cl/118610043

LGTM=rsc
R=rsc, iant
CC=golang-codereviews
https://golang.org/cl/120220043

LGTM=rsc
R=rsc, iant
CC=golang-codereviews
https://golang.org/cl/115300044

LGTM=rsc
R=rsc, iant
CC=golang-codereviews
https://golang.org/cl/114420043

The manpages says SA_RESTORER is obsolete, and indeed, not every architecture
support it. However, sadly it's required on x86_64, see http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/tree/arch/x86/kernel/signal.c?id=26bcd8b72563b4c54892c4c2a409f6656fb8ae8b#n430, so only use it on x86.

LGTM=rsc
R=rsc, iant
CC=golang-codereviews
https://golang.org/cl/115450043

Rather than switch on thechar.

LGTM=rsc, dave
R=rsc, iant, dave
CC=golang-codereviews
https://golang.org/cl/119330043

LGTM=bradfitz, dave, ruiu
R=rsc, iant, bradfitz, dave, ruiu
CC=golang-codereviews
https://golang.org/cl/116610043

Fixes build for nacl/386.

LGTM=dave
R=khr, bradfitz, dave, dan.kortschak, rsc
CC=golang-codereviews
https://golang.org/cl/121080043

Encode MOV $0, %ax as XOR %eax, %eax instead of
XOR %rax, %rax. If an operand register does not
need REX.w bit (i.e. not one of R8-R15), it is
encoded in 2 bytes instead of 3 bytes.

LGTM=rsc
R=golang-codereviews, gobot, rsc
CC=golang-codereviews
https://golang.org/cl/115580044

Instead of immediately completing pointer type mappings, add them to
a queue to allow them to be completed later.  This fixes issues	caused
by Type() returning arbitrary in-progress type mappings.

Fixes #8368.
Fixes #8441.

LGTM=iant
R=golang-codereviews, iant
CC=golang-codereviews
https://golang.org/cl/122850043

Instead of including <sys/types.h> to get size_t, instead include
the ISO C standard <stddef.h> header, which defines fewer additional
types at risk of colliding with the user code.  In particular, this
prevents collisions between <sys/types.h>'s userspace definitions with
the kernel definitions needed by defs_linux.go.

Also, -cdefs mode uses #pragma pack, so we can keep misaligned fields.

Fixes #8477.

LGTM=iant
R=golang-codereviews, iant
CC=golang-codereviews
https://golang.org/cl/120610043