Skip to content

G
golang
Switch branch/tag
  1. 10 Mar, 2016 27 commits
  3. 09 Mar, 2016 13 commits
    • Andrew Gerrand's avatar
      doc: add doc.Example.Unordered to go1.7.txt · c2400e31
      Andrew Gerrand authored 
      Change-Id: I142a9f97303e3bfbd9522fd061530c0a91305389
Reviewed-on: https://go-review.googlesource.com/20500Reviewed-by: 's avatarMinux Ma <minux@golang.org>
      c2400e31
    • Josh Bleecher Snyder's avatar
      cmd/compile: make alg gen prologue/epilogue match · e0032df8
      Josh Bleecher Snyder authored 
      With this, the start and end of geneq and genhash
are parallel. This removes a few rare nilchecks
from generated hash functions, but nothing
to write home about.

Change-Id: I3b4836111d04daa6f6834a579bbec374a3f42c70
Reviewed-on: https://go-review.googlesource.com/20456
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: 's avatarDavid Crawshaw <crawshaw@golang.org>
      e0032df8
    • Ian Lance Taylor's avatar
      cmd/compile: remove remaining nodeSeqIterate calls · cd6619d2
      Ian Lance Taylor authored 
      Mix in several other minor cleanups, including adding some new methods
to Nodes: Index, Addr, SetIndex, SetNodes.

Passes toolstash -cmp.

Update #14473.

Change-Id: I8bd4ae3fde7c5e20ba66e7dd1654fbc70c3ddeb8
Reviewed-on: https://go-review.googlesource.com/20491Reviewed-by: 's avatarBrad Fitzpatrick <bradfitz@golang.org>
      cd6619d2
    • David Crawshaw's avatar
      cmd/link: prune unused methods · 862b9ddd
      David Crawshaw authored 
      Today the linker keeps all methods of reachable types. This is
necessary if a program uses reflect.Value.Call. But while use of
reflection is widespread in Go for encoders and decoders, using
it to call a method is rare.

This CL looks for the use of reflect.Value.Call in a program, and
if it is absent, adopts a (reasonably conservative) method pruning
strategy as part of dead code elimination. Any method that is
directly called is kept, and any method that matches a used
interface's method signature is kept.

Whether or not a method body is kept is determined by the relocation
from its receiver's *rtype to its *rtype. A small change in the
compiler marks these relocations as R_METHOD so they can be easily
collected and manipulated by the linker.

As a bonus, this technique removes the text segment of methods that
have been inlined. Looking at the output of building cmd/objdump with
-ldflags=-v=2 shows that inlined methods like
runtime.(*traceAllocBlockPtr).ptr are removed from the program.

Relatively little work is necessary to do this. Linking two
examples, jujud and cmd/objdump show no more than +2% link time.

Binaries that do not use reflect.Call.Value drop 4 - 20% in size:

	addr2line: -793KB (18%)
	asm:       -346KB (8%)
	cgo:       -490KB (10%)
	compile:   -564KB (4%)
	dist:      -736KB (17%)
	fix:       -404KB (12%)
	link:      -328KB (7%)
	nm:        -827KB (19%)
	objdump:   -712KB (16%)
	pack:      -327KB (14%)
	yacc:      -350KB (10%)

Binaries that do use reflect.Call.Value see a modest size decrease
of 2 - 6% thanks to pruning of unexported methods:

	api:    -151KB (3%)
	cover:  -222KB (4%)
	doc:    -106KB (2.5%)
	pprof:  -314KB (3%)
	trace:  -357KB (4%)
	vet:    -187KB (2.7%)
	jujud:  -4.4MB (5.8%)
	cmd/go: -384KB (3.4%)

The trivial Hello example program goes from 2MB to 1.68MB:

	package main

	import "fmt"

	func main() {
		fmt.Println("Hello, 世界")
	}

Method pruning also helps when building small binaries with
"-ldflags=-s -w". The above program goes from 1.43MB to 1.2MB.

Unfortunately the linker can only tell if reflect.Value.Call has been
statically linked, not if it is dynamically used. And while use is
rare, it is linked into a very common standard library package,
text/template. The result is programs like cmd/go, which don't use
reflect.Value.Call, see limited benefit from this CL. If binary size
is important enough it may be possible to address this in future work.

For #6853.

Change-Id: Iabe90e210e813b08c3f8fd605f841f0458973396
Reviewed-on: https://go-review.googlesource.com/20483Reviewed-by: 's avatarRuss Cox <rsc@golang.org>
      862b9ddd
    • Brad Fitzpatrick's avatar
      doc: fix bogus HTML in contribute.html · f02dc513
      Brad Fitzpatrick authored 
      Introduced in https://golang.org/cl/20462

Change-Id: I6c55f87228f0980058a10f204b57ead7594e3492
Reviewed-on: https://go-review.googlesource.com/20490Reviewed-by: 's avatarAndrew Gerrand <adg@golang.org>
      f02dc513
    • Brad Fitzpatrick's avatar
      cmd/compile: shrink tables · 0ac0e22f
      Brad Fitzpatrick authored 
      Drops cmd/binary size from 14.41 MiB to 11.42 MiB.

Before:

   text    data     bss     dec     hex filename
8121210 3521696  737960 12380866         bceac2 ../pkg/tool/linux_amd64/compile

bradfitz@dev-bradfitz-debian2:~/go/src$ ls -l ../pkg/tool/linux_amd64/compile
-rwxr-xr-x 1 bradfitz bradfitz 15111272 Mar  8 23:32 ../pkg/tool/linux_amd64/compile

  a2afc0      51312 R html.statictmp_0085
  6753f0      56592 T cmd/internal/obj/x86.doasm
  625480      58080 T cmd/compile/internal/gc.typecheck1
  f34c40      65688 D runtime.trace
  be0a20     133552 D cmd/compile/internal/ppc64.varianttable
  c013e0     265856 D cmd/compile/internal/arm.progtable
  c42260     417280 D cmd/compile/internal/amd64.progtable
  ca8060     417280 D cmd/compile/internal/x86.progtable
  f44ce0     500640 D cmd/internal/obj/arm64.oprange
  d0de60     534208 D cmd/compile/internal/ppc64.progtable
  d90520     667520 D cmd/compile/internal/arm64.progtable
  e334a0     790368 D cmd/compile/internal/mips64.progtable
  a3e8c0    1579362 r runtime.pclntab

After:

   text    data     bss     dec     hex filename
8128226  375954  246432 8750612  858614 ../pkg/tool/linux_amd64/compile

-rwxr-xr-x 1 bradfitz bradfitz 11971432 Mar  8 23:35 ../pkg/tool/linux_amd64/compile

  6436d0      43936 T cmd/compile/internal/gc.walkexpr
  c13ca0      45056 D cmd/compile/internal/ssa.opcodeTable
  5d8ea0      50256 T cmd/compile/internal/gc.(*state).expr
  818c50      50448 T cmd/compile/internal/ssa.rewriteValueAMD64_OpMove
  a2d0e0      51312 R html.statictmp_0085
  6753d0      56592 T cmd/internal/obj/x86.doasm
  625460      58080 T cmd/compile/internal/gc.typecheck1
  c38fe0      65688 D runtime.trace
  a409e0    1578810 r runtime.pclntab

Fixes #14703

Change-Id: I2177596d5c7fd67db0a3c423cd90801cf52adb12
Reviewed-on: https://go-review.googlesource.com/20450Reviewed-by: 's avatarMatthew Dempsky <mdempsky@google.com>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
      0ac0e22f
    • Martin Möhrmann's avatar
      fmt: refactor pointer formatting and improve tests · 8e231567
      Martin Möhrmann authored 
      Uses a switch statement for direct format function selection
similar to other types verb handling in fmt.

Applies padding also to nil pointers formatted with %v.

Guards against "slice bounds out of range" panic in TestSprintf
when a pointer test results in a formatted string s
that is shorter than the index i the pointer should appear in.

Adds more and rearranges tests.

Fixes #14712
Fixes #14714

Change-Id: Iaf5ae37b7e6ba7d27d528d199f2b2eb9d5829b8c
Reviewed-on: https://go-review.googlesource.com/20371
Run-TryBot: Rob Pike <r@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: 's avatarRob Pike <r@golang.org>
      8e231567
    • Alexandru Moșoi's avatar
      cmd/compile: constant fold more of IsInBounds and IsSliceInBounds · bbd3ffbd
      Alexandru Moșoi authored 
      Fixes #14721

Change-Id: Id1d5a819e5c242b91a37c4e464ed3f00c691aff5
Reviewed-on: https://go-review.googlesource.com/20482Reviewed-by: 's avatarKeith Randall <khr@golang.org>
Run-TryBot: Alexandru Moșoi <alexandru@mosoi.ro>
TryBot-Result: Gobot Gobot <gobot@golang.org>
      bbd3ffbd
    • Matthew Dempsky's avatar
      cmd/compile: switch Eqtype and (*Type).Compare to use recvParamsResults · b594b8b0
      Matthew Dempsky authored 
      Change-Id: I5365b94b815bfb4795db643415c2df51fc815ea1
Reviewed-on: https://go-review.googlesource.com/20459
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: 's avatarDave Cheney <dave@cheney.net>
      b594b8b0
    • Richard Miller's avatar
      runtime: Plan 9 - prevent preemption by GC while exiting · 6b59d618
      Richard Miller authored 
      On Plan 9, there's no "kill all threads" system call, so exit is done
by sending a "go: exit" note to each OS process.  If concurrent GC
occurs during this loop, deadlock sometimes results.  Prevent this by
incrementing m.locks before sending notes.

Change-Id: I31aa15134ff6e42d9a82f9f8a308620b3ad1b1b1
Reviewed-on: https://go-review.googlesource.com/20477Reviewed-by: 's avatarBrad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
      6b59d618
    • Richard Miller's avatar
      syscall: add NO_LOCAL_POINTERS to syscall.exit in plan9_arm · 87103a1a
      Richard Miller authored 
      This prevents a fatal "missing stackmap" error if garbage collection
occurs during exit.

Also annotate argument sizes for "go vet".

Change-Id: I2473e0ef6aef8f26d0bbeaee9bd8f8a52eaaf941
Reviewed-on: https://go-review.googlesource.com/20476Reviewed-by: 's avatarBrad Fitzpatrick <bradfitz@golang.org>
      87103a1a
    • Alexandru Moșoi's avatar
      cmd/compile/internal/ssa: lower builtins much later · dfcb853d
      Alexandru Moșoi authored 
      * Move lowering into a separate pass.
* SliceLen/SliceCap is now available to various intermediate passes
which use useful for bounds checking.
* Add a second opt pass to handle the new opportunities

Decreases the code size of binaries in pkg/tool/linux_amd64
by ~45K.

Updates #14564 #14606

Change-Id: I5b2bd6202181c50623a3585fbf15c0d6db6d4685
Reviewed-on: https://go-review.googlesource.com/20172
Run-TryBot: Alexandru Moșoi <alexandru@mosoi.ro>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: 's avatarDavid Chase <drchase@google.com>
      dfcb853d
    • Matthew Dempsky's avatar
      cmd/compile: eliminate IterParams · aa3650f0
      Matthew Dempsky authored 
      It's only used once, so just make the caller responsible for iterating
both the receiver and input params.

Change-Id: Icb34f3f0cf96e80fbe27f3f49d12eddc26599b92
Reviewed-on: https://go-review.googlesource.com/20454Reviewed-by: 's avatarDave Cheney <dave@cheney.net>
      aa3650f0