1
0
mirror of https://github.com/golang/go synced 2024-11-13 17:50:23 -07:00
Commit Graph

2693 Commits

Author SHA1 Message Date
Cherry Zhang
8ff4260777 cmd/compile: intrinsify Ctz, Bswap on ARM
Atomic ops on ARM are implemented with kernel calls, so they are
not intrinsified.

Change-Id: I0e7cc2e5526ae1a3d24b4b89be1bd13db071f8ef
Reviewed-on: https://go-review.googlesource.com/28977
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
2016-09-12 19:26:31 +00:00
Josh Bleecher Snyder
dfc56a4cd3 cmd/compile: statically initialize some interface values
When possible, emit static data rather than
init functions for interface values.

This:

* cuts 32k off cmd/go
* removes several error values from runtime init
* cuts the size of the image/color/palette compiled package from 103k to 34k
* reduces the time to build the package in #15520 from 8s to 1.5s

Fixes #6289
Fixes #15528

Change-Id: I317112da17aadb180c958ea328ab380f83e640b4
Reviewed-on: https://go-review.googlesource.com/26668
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2016-09-12 14:31:26 +00:00
Josh Bleecher Snyder
1fe4c81282 cmd/compile: don't crash on complex(0())
Fixes #17038.

Change-Id: Iaf6294361050040830af1d60cd48f263223d9356
Reviewed-on: https://go-review.googlesource.com/28966
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2016-09-11 20:43:51 +00:00
Cherry Zhang
4354ffd38b cmd/compile: intrinsify Ctz, Bswap, and some atomics on ARM64
Change-Id: Ia5bf72b70e6f6522d6fb8cd050e78f862d37b5ae
Reviewed-on: https://go-review.googlesource.com/27936
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2016-09-08 19:45:25 +00:00
Keith Randall
83c73a85db cmd/compile: ignore contentEscapes for marking nodes as escaping
Redo of CL 28575 with fixed test.
We're in a pre-KeepAlive world for a bit yet, the old tests
were in a client which was in a post-KeepAlive world.

Change-Id: I114fd630339d761ab3306d1d99718d3cb973678d
Reviewed-on: https://go-review.googlesource.com/28582
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2016-09-07 06:59:22 +00:00
Brad Fitzpatrick
bdb3b790c6 Revert of cmd/compile: ignore contentEscapes for marking nodes as escaping
Reason for revert: broke the build due to cherrypick;
relies on an unsubmitted parent CL.

Original issue's description:
> cmd/compile: ignore contentEscapes for marking nodes as escaping
> 
> We can still stack allocate and VarKill nodes which don't
> escape but their content does.
> 
> Fixes #16996
> 
> Change-Id: If8aa0fcf2c327b4cb880a3d5af8d213289e6f6bf
> Reviewed-on: https://go-review.googlesource.com/28575
> Run-TryBot: Keith Randall <khr@golang.org>
> TryBot-Result: Gobot Gobot <gobot@golang.org>
> Reviewed-by: David Chase <drchase@google.com>
> 

Change-Id: Ie1a325209de14d70af6acb2d78269b7a0450da7a
Reviewed-on: https://go-review.googlesource.com/28578
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2016-09-07 03:23:44 +00:00
Keith Randall
923a74ce77 cmd/compile: ignore contentEscapes for marking nodes as escaping
We can still stack allocate and VarKill nodes which don't
escape but their content does.

Fixes #16996

Change-Id: If8aa0fcf2c327b4cb880a3d5af8d213289e6f6bf
Reviewed-on: https://go-review.googlesource.com/28575
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
2016-09-07 02:07:03 +00:00
David Chase
a6edffb286 cmd/compile: add BVC/BVS to branch ops in ppc64/prog.go
Includes test case shown to fail with unpatched compiler.

Fixes #17005.

Change-Id: I49b7b1a3f02736d85846a2588018b73f68d50320
Reviewed-on: https://go-review.googlesource.com/28573
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Minux Ma <minux@golang.org>
2016-09-07 01:30:34 +00:00
David Chase
0e0ab20334 cmd/compile: remove ld/st-followed nil checks for PPC64
Enabled checks (except for DUFF-ops which aren't implemented yet).
Added ppc64le to relevant test.

Also updated register list to reflect no-longer-reserved-
for-constants status (file was missed in that change).

Updates #16010.

Change-Id: I31b1aac19e14994f760f2ecd02edbeb1f78362e7
Reviewed-on: https://go-review.googlesource.com/28548
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2016-09-06 18:52:13 +00:00
Cherry Zhang
644c16c76c cmd/compile: fix intrinsifying sync/atomic.Swap* on AMD64
It should alias to Xchg instead of Swap. Found when testing #16985.

Change-Id: If9fd734a1f89b8b2656f421eb31b9d1b0d95a49f
Reviewed-on: https://go-review.googlesource.com/28512
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2016-09-06 14:44:50 +00:00
Cherry Zhang
f1ef5a06d2 cmd/compile: mark some AMD64 atomic ops as clobberFlags
Fixes #16985.

Change-Id: I5954db28f7b70dd3ac7768e471d5df871a5b20f9
Reviewed-on: https://go-review.googlesource.com/28510
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2016-09-06 14:26:18 +00:00
Josh Bleecher Snyder
be8a1c6139 test: add test for issue 15895
It was fixed earlier in the Go 1.8 cycle.
Add a test.

Fixes #15895

Change-Id: I5834831235d99b9fcf21b435932cdd7ac6dc2c6e
Reviewed-on: https://go-review.googlesource.com/28476
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-09-04 00:15:41 +00:00
Martin Möhrmann
8895a99c9f cmd/compile: disallow typed non-integer constant len and cap make arguments
make(T, n, m) returns a slice of type T with length n and capacity m
where "The size arguments n and m must be of integer type or untyped."
https://tip.golang.org/ref/spec#Making_slices_maps_and_channels

The failure to reject typed non-integer size arguments in make
during compile time was uncovered after https://golang.org/cl/27851
changed the generation of makeslice calls.

Fixes   #16940
Updates #16949

Change-Id: Ib1e3576f0e6ad199c9b16b7a50c2db81290c63b4
Reviewed-on: https://go-review.googlesource.com/28301
Reviewed-by: Joe Tsai <thebrokentoaster@gmail.com>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
2016-09-01 20:29:03 +00:00
Cherry Zhang
1c53a1b197 cmd/compile: fix scheduling of memory-producing tuple ops
Intrinsified atomic op produces <value,memory>. Make sure this
memory is considered in the store chain calculation.

Fixes #16948.

Change-Id: I029f164b123a7e830214297f8373f06ea0bf1e26
Reviewed-on: https://go-review.googlesource.com/28350
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2016-09-01 14:25:46 +00:00
Martin Möhrmann
0dae9dfb08 cmd/compile: improve string iteration performance
Generate a for loop for ranging over strings that only needs to call
the runtime function charntorune for non ASCII characters.

This provides faster iteration over ASCII characters and slightly
faster iteration for other characters.

The runtime function charntorune is changed to take an index from where
to start decoding and returns the index after the last byte belonging
to the decoded rune.

All call sites of charntorune in the runtime are replaced by a for loop
that will be transformed by the compiler instead of calling the charntorune
function directly.

go binary size decreases by 80 bytes.
godoc binary size increases by around 4 kilobytes.

runtime:

name                           old time/op  new time/op  delta
RuneIterate/range/ASCII-4      43.7ns ± 3%  10.3ns ± 4%  -76.33%  (p=0.000 n=44+45)
RuneIterate/range/Japanese-4   72.5ns ± 2%  62.8ns ± 2%  -13.41%  (p=0.000 n=49+50)
RuneIterate/range1/ASCII-4     43.5ns ± 2%  10.4ns ± 3%  -76.18%  (p=0.000 n=50+50)
RuneIterate/range1/Japanese-4  72.5ns ± 2%  62.9ns ± 2%  -13.26%  (p=0.000 n=50+49)
RuneIterate/range2/ASCII-4     43.5ns ± 3%  10.3ns ± 2%  -76.22%  (p=0.000 n=48+47)
RuneIterate/range2/Japanese-4  72.4ns ± 2%  62.7ns ± 2%  -13.47%  (p=0.000 n=50+50)

strings:

name                 old time/op    new time/op    delta
IndexRune-4            64.7ns ± 5%    22.4ns ± 3%  -65.43%  (p=0.000 n=25+21)
MapNoChanges-4          269ns ± 2%     157ns ± 2%  -41.46%  (p=0.000 n=23+24)
Fields-4               23.0ms ± 2%    19.7ms ± 2%  -14.35%  (p=0.000 n=25+25)
FieldsFunc-4           23.1ms ± 2%    19.6ms ± 2%  -14.94%  (p=0.000 n=25+24)

name                 old speed      new speed      delta
Fields-4             45.6MB/s ± 2%  53.2MB/s ± 2%  +16.87%  (p=0.000 n=24+25)
FieldsFunc-4         45.5MB/s ± 2%  53.5MB/s ± 2%  +17.57%  (p=0.000 n=25+24)

Updates #13162

Change-Id: I79ffaf828d82bf9887592f08e5cad883e9f39701
Reviewed-on: https://go-review.googlesource.com/27853
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
Run-TryBot: Martin Möhrmann <martisch@uos.de>
2016-08-30 18:17:20 +00:00
Martin Möhrmann
e6f9f39ce5 cmd/compile: generate makeslice calls with int arguments
Where possible generate calls to runtime makeslice with int arguments
during compile time instead of makeslice with int64 arguments.

This eliminates converting arguments for calls to makeslice with
int64 arguments for platforms where int64 values do not fit into
arguments of type int.

godoc 386 binary shrinks by approximately 12 kilobyte.

amd64:
name         old time/op  new time/op  delta
MakeSlice-2  29.8ns ± 1%  29.8ns ± 1%   ~     (p=1.000 n=24+24)

386:
name         old time/op  new time/op  delta
MakeSlice-2  52.3ns ± 0%  45.9ns ± 0%  -12.17%  (p=0.000 n=25+22)

Fixes  #15357

Change-Id: Icb8701bb63c5a83877d26c8a4b78e782ba76de7c
Reviewed-on: https://go-review.googlesource.com/27851
Run-TryBot: Martin Möhrmann <martisch@uos.de>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
2016-08-29 18:25:33 +00:00
Cherry Zhang
7f27f1dfdd cmd/compile: add MIPS64 optimizations, SSA on by default
Add the following optimizations:
- fold constants
- fold address into load/store
- simplify extensions and conditional branches
- remove nil checks

Turn on SSA on MIPS64 by default, and toggle the tests.

Fixes #16359.

Change-Id: I7f1e38c2509e22e42cd024e712990ebbe47176bd
Reviewed-on: https://go-review.googlesource.com/27870
Run-TryBot: Cherry Zhang <cherryyz@google.com>
Reviewed-by: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-08-26 19:45:06 +00:00
David Crawshaw
14efaa0dc3 cmd/compile: qualify unexported fields of unnamed types
The compiler was canonicalizing unnamed types of the form

	struct { i int }

across packages, even though an unexported field i should not be
accessible from other packages.

The fix requires both qualifying the field name in the string used by
the compiler to distinguish the type, and ensuring the struct's pkgpath
is set in the rtype version of the data when the type being written is
not part of the localpkg.

Fixes #16616

Change-Id: Ibab160b8b5936dfa47b17dbfd48964a65586785b
Reviewed-on: https://go-review.googlesource.com/27791
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
2016-08-26 11:46:15 +00:00
Josh Bleecher Snyder
0bc94a8864 cmd/compile: when inlining ==, don’t take the address of the values
This CL reworks walkcompare for clarity and concision.
It also makes one significant functional change.
(The functional change is hard to separate cleanly
from the cleanup, so I just did them together.)
When inlining and unrolling an equality comparison
for a small struct or array, compare the elements like:

a[0] == b[0] && a[1] == b[1]

rather than

pa := &a
pb := &b
pa[0] == pb[0] && pa[1] == pb[1]

The result is the same, but taking the address
and working through the indirect
forces the backends to generate less efficient code.

This is only an improvement with the SSA backend.
However, every port but s390x now has a working
SSA backend, and switching to the SSA backend
by default everywhere is a priority for Go 1.8.
It thus seems reasonable to start to prioritize
SSA performance over the old backend.

Updates #15303


Sample code:

type T struct {
	a, b int8
}

func g(a T) bool {
	return a == T{1, 2}
}


SSA before:

"".g t=1 size=80 args=0x10 locals=0x8
	0x0000 00000 (badeq.go:7)	TEXT	"".g(SB), $8-16
	0x0000 00000 (badeq.go:7)	SUBQ	$8, SP
	0x0004 00004 (badeq.go:7)	FUNCDATA	$0, gclocals·23e8278e2b69a3a75fa59b23c49ed6ad(SB)
	0x0004 00004 (badeq.go:7)	FUNCDATA	$1, gclocals·33cdeccccebe80329f1fdbee7f5874cb(SB)
	0x0004 00004 (badeq.go:8)	MOVBLZX	"".a+16(FP), AX
	0x0009 00009 (badeq.go:8)	MOVB	AL, "".autotmp_0+6(SP)
	0x000d 00013 (badeq.go:8)	MOVBLZX	"".a+17(FP), AX
	0x0012 00018 (badeq.go:8)	MOVB	AL, "".autotmp_0+7(SP)
	0x0016 00022 (badeq.go:8)	MOVB	$0, "".autotmp_1+4(SP)
	0x001b 00027 (badeq.go:8)	MOVB	$1, "".autotmp_1+4(SP)
	0x0020 00032 (badeq.go:8)	MOVB	$2, "".autotmp_1+5(SP)
	0x0025 00037 (badeq.go:8)	MOVBLZX	"".autotmp_0+6(SP), AX
	0x002a 00042 (badeq.go:8)	MOVBLZX	"".autotmp_1+4(SP), CX
	0x002f 00047 (badeq.go:8)	CMPB	AL, CL
	0x0031 00049 (badeq.go:8)	JNE	70
	0x0033 00051 (badeq.go:8)	MOVBLZX	"".autotmp_0+7(SP), AX
	0x0038 00056 (badeq.go:8)	CMPB	AL, $2
	0x003a 00058 (badeq.go:8)	SETEQ	AL
	0x003d 00061 (badeq.go:8)	MOVB	AL, "".~r1+24(FP)
	0x0041 00065 (badeq.go:8)	ADDQ	$8, SP
	0x0045 00069 (badeq.go:8)	RET
	0x0046 00070 (badeq.go:8)	MOVB	$0, AL
	0x0048 00072 (badeq.go:8)	JMP	61

SSA after:

"".g t=1 size=32 args=0x10 locals=0x0
	0x0000 00000 (badeq.go:7)	TEXT	"".g(SB), $0-16
	0x0000 00000 (badeq.go:7)	NOP
	0x0000 00000 (badeq.go:7)	NOP
	0x0000 00000 (badeq.go:7)	FUNCDATA	$0, gclocals·23e8278e2b69a3a75fa59b23c49ed6ad(SB)
	0x0000 00000 (badeq.go:7)	FUNCDATA	$1, gclocals·33cdeccccebe80329f1fdbee7f5874cb(SB)
	0x0000 00000 (badeq.go:8)	MOVBLZX	"".a+8(FP), AX
	0x0005 00005 (badeq.go:8)	CMPB	AL, $1
	0x0007 00007 (badeq.go:8)	JNE	25
	0x0009 00009 (badeq.go:8)	MOVBLZX	"".a+9(FP), CX
	0x000e 00014 (badeq.go:8)	CMPB	CL, $2
	0x0011 00017 (badeq.go:8)	SETEQ	AL
	0x0014 00020 (badeq.go:8)	MOVB	AL, "".~r1+16(FP)
	0x0018 00024 (badeq.go:8)	RET
	0x0019 00025 (badeq.go:8)	MOVB	$0, AL
	0x001b 00027 (badeq.go:8)	JMP	20


Change-Id: I120185d58012b7bbcdb1ec01225b5b08d0855d86
Reviewed-on: https://go-review.googlesource.com/22277
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2016-08-25 17:51:10 +00:00
Josh Bleecher Snyder
6286188986 cmd/compile: optimize integer "in range" expressions
Use unsigned comparisons to reduce from
two comparisons to one for integer "in range"
checks, such as a <= b && b < c.
We already do this for bounds checks.
Extend it to user code.

This is much easier to do in the front end than SSA.
A back end optimization would be more powerful,
but this is a good start.

This reduces the power of some of SSA prove
inferences (#16653), but those regressions appear
to be rare and not worth holding this CL for.

Fixes #15844.
Fixes #16697.

strconv benchmarks:

name                          old time/op  new time/op   delta
Atof64Decimal-8               41.4ns ± 3%   38.9ns ± 2%   -5.89%  (p=0.000 n=24+25)
Atof64Float-8                 48.5ns ± 0%   46.8ns ± 3%   -3.64%  (p=0.000 n=20+23)
Atof64FloatExp-8              97.7ns ± 4%   93.5ns ± 1%   -4.25%  (p=0.000 n=25+20)
Atof64Big-8                    187ns ± 8%    162ns ± 2%  -13.54%  (p=0.000 n=24+22)
Atof64RandomBits-8             250ns ± 6%    233ns ± 5%   -6.76%  (p=0.000 n=25+25)
Atof64RandomFloats-8           160ns ± 0%    152ns ± 0%   -5.00%  (p=0.000 n=21+22)
Atof32Decimal-8               41.1ns ± 1%   38.7ns ± 2%   -5.86%  (p=0.000 n=24+24)
Atof32Float-8                 46.1ns ± 1%   43.5ns ± 3%   -5.63%  (p=0.000 n=21+24)
Atof32FloatExp-8               101ns ± 4%    100ns ± 2%   -1.59%  (p=0.000 n=24+23)
Atof32Random-8                 136ns ± 3%    133ns ± 3%   -2.83%  (p=0.000 n=22+22)
Atoi-8                        33.8ns ± 3%   30.6ns ± 3%   -9.51%  (p=0.000 n=24+25)
AtoiNeg-8                     31.6ns ± 3%   29.1ns ± 2%   -8.05%  (p=0.000 n=23+24)
Atoi64-8                      48.6ns ± 1%   43.8ns ± 1%   -9.81%  (p=0.000 n=20+23)
Atoi64Neg-8                   47.1ns ± 4%   42.0ns ± 2%  -10.83%  (p=0.000 n=25+25)
FormatFloatDecimal-8           177ns ± 9%    178ns ± 6%     ~     (p=0.460 n=25+25)
FormatFloat-8                  282ns ± 6%    282ns ± 3%     ~     (p=0.954 n=25+22)
FormatFloatExp-8               259ns ± 7%    255ns ± 6%     ~     (p=0.089 n=25+24)
FormatFloatNegExp-8            253ns ± 6%    254ns ± 6%     ~     (p=0.941 n=25+24)
FormatFloatBig-8               340ns ± 6%    341ns ± 8%     ~     (p=0.600 n=22+25)
AppendFloatDecimal-8          79.4ns ± 0%   80.6ns ± 6%     ~     (p=0.861 n=20+25)
AppendFloat-8                  175ns ± 3%    174ns ± 0%     ~     (p=0.722 n=25+20)
AppendFloatExp-8               142ns ± 4%    142ns ± 2%     ~     (p=0.948 n=25+24)
AppendFloatNegExp-8            137ns ± 2%    138ns ± 2%   +0.70%  (p=0.001 n=24+25)
AppendFloatBig-8               218ns ± 3%    218ns ± 4%     ~     (p=0.596 n=25+25)
AppendFloatBinaryExp-8        80.0ns ± 4%   78.0ns ± 1%   -2.43%  (p=0.000 n=24+21)
AppendFloat32Integer-8        82.3ns ± 3%   79.3ns ± 4%   -3.69%  (p=0.000 n=24+25)
AppendFloat32ExactFraction-8   143ns ± 2%    143ns ± 0%     ~     (p=0.177 n=23+19)
AppendFloat32Point-8           175ns ± 3%    175ns ± 3%     ~     (p=0.062 n=24+25)
AppendFloat32Exp-8             139ns ± 2%    137ns ± 4%   -1.05%  (p=0.001 n=24+24)
AppendFloat32NegExp-8          134ns ± 0%    137ns ± 4%   +2.06%  (p=0.000 n=22+25)
AppendFloat64Fixed1-8         97.8ns ± 0%   98.6ns ± 3%     ~     (p=0.711 n=20+25)
AppendFloat64Fixed2-8          110ns ± 3%    110ns ± 5%   -0.45%  (p=0.037 n=24+24)
AppendFloat64Fixed3-8          102ns ± 3%    102ns ± 3%     ~     (p=0.684 n=24+24)
AppendFloat64Fixed4-8          112ns ± 3%    110ns ± 0%   -1.43%  (p=0.000 n=25+18)
FormatInt-8                   3.18µs ± 4%   3.10µs ± 6%   -2.54%  (p=0.001 n=24+25)
AppendInt-8                   1.81µs ± 5%   1.80µs ± 5%     ~     (p=0.648 n=25+25)
FormatUint-8                   812ns ± 6%    816ns ± 6%     ~     (p=0.777 n=25+25)
AppendUint-8                   536ns ± 4%    538ns ± 3%     ~     (p=0.798 n=20+22)
Quote-8                        605ns ± 6%    602ns ± 9%     ~     (p=0.573 n=25+25)
QuoteRune-8                   99.5ns ± 8%  100.2ns ± 7%     ~     (p=0.432 n=25+25)
AppendQuote-8                  361ns ± 3%    363ns ± 4%     ~     (p=0.085 n=25+25)
AppendQuoteRune-8             23.3ns ± 3%   22.4ns ± 2%   -3.79%  (p=0.000 n=25+24)
UnquoteEasy-8                  146ns ± 4%    145ns ± 5%     ~     (p=0.112 n=24+24)
UnquoteHard-8                  804ns ± 6%    771ns ± 6%   -4.10%  (p=0.000 n=25+24)

Change-Id: Ibd384e46e90f1cfa40503c8c6352a54c65b72980
Reviewed-on: https://go-review.googlesource.com/27652
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-08-25 03:49:16 +00:00
Keith Randall
3e270ab80b cmd/compile: clean up ctz ops
Now that we have ops that can return 2 results, have BSF return a result
and flags.  We can then get rid of the redundant comparison and use CMOV
instead of CMOVconst ops.

Get rid of a bunch of the ops we don't use.  Ctz{8,16}, plus all the Clzs,
and CMOVNEs.  I don't think we'll ever use them, and they would be easy
to add back if needed.

Change-Id: I8858a1d017903474ea7e4002fc76a6a86e7bd487
Reviewed-on: https://go-review.googlesource.com/27630
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
2016-08-23 23:45:12 +00:00
Robert Griesemer
6394eb378e cmd/compile: export package for _ (blank) struct fields
Blank struct fields are regular unexported fields. Two
blank fields are different if they are from different
packages. In order to correctly differentiate them, the
compiler needs the package information. Add it to the
export data.

Fixes #15514.

Change-Id: I421aaca22b542fcd0d66b2d2db777249cad78df6
Reviewed-on: https://go-review.googlesource.com/27639
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2016-08-23 23:40:36 +00:00
Than McIntosh
78fac02cfd test: add test for gccgo issue #15722
Change-Id: I4faf9a55414e217f0c48528efb13ab8fdcd9bb16
Reviewed-on: https://go-review.googlesource.com/24845
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
2016-08-23 20:43:59 +00:00
Martin Möhrmann
9aea69d6dc cmd/compile: fix binary import of unsafe.Pointer literals
Add a type conversion to uintptr for untyped constants
before the conversion to unsafe.Pointer.

Fixes #16317

Change-Id: Ib85feccad1019e687e7eb6135890b64b82fb87fb
Reviewed-on: https://go-review.googlesource.com/27441
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Robert Griesemer <gri@golang.org>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-08-23 18:03:07 +00:00
Ian Lance Taylor
25d18954f6 test: add test case that gccgo miscompiled
Change-Id: I384eac632a4a87c12977e56a7d7bad7614305c51
Reviewed-on: https://go-review.googlesource.com/25143
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2016-08-23 14:19:45 +00:00
Josh Bleecher Snyder
e26499153e cmd/compile: use a map to track const switch cases
This is simpler than the sorting technique.
It also allows us to simplify or eliminate
some of the sorting decisions.

Most important, sorting will not work when case clauses
represent ranges of integers: There is no correct
sort order that allows overlap detection by comparing
neighbors. Using a map allows of a cheap, simple
approach to ranges, namely to insert every int
in the map. The equivalent approach for sorting
means juggling temporary Nodes for every int,
which is a lot more expensive.

Change-Id: I84df3cb805992a1b04d14e0e4b2334f943e0ce05
Reviewed-on: https://go-review.googlesource.com/26766
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2016-08-23 05:28:33 +00:00
Josh Bleecher Snyder
bd2838be77 cmd/compile: use a map to detect duplicate type switch cases
This is a bit simpler than playing sorting games,
and it is clearer that it generates errors
in the correct (source) order.

It also allows us to simplify sorting.

It also prevents quadratic error messages for
(pathological) inputs with many duplicate type cases.

While we’re here, refactoring deduping into separate functions.

Negligible compilebench impact.

Fixes #15912.

Change-Id: I6cc19edd38875389a70ccbdbdf0d9b7d5ac5946f
Reviewed-on: https://go-review.googlesource.com/26762
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2016-08-23 05:17:05 +00:00
Josh Bleecher Snyder
1a3006b035 test: expand switch dead code test to include a range
Change-Id: If443ffb50b140c466dcf4cc5340f44948bfa46a9
Reviewed-on: https://go-review.googlesource.com/26765
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2016-08-23 05:12:39 +00:00
Josh Bleecher Snyder
cf20525bf4 cmd/compile: set correct line number for multiple defaults in switch error
Fixes #15911.

Change-Id: I500533484de61aa09abe4cecb010445e3176324e
Reviewed-on: https://go-review.googlesource.com/26760
TryBot-Result: Gobot Gobot <gobot@golang.org>
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2016-08-22 19:56:06 +00:00
Martin Möhrmann
6a393dc64f cmd/compile: fix compilation of math.Sqrt when used as a statement
Fixes #16804

Change-Id: I669c2c24d3135cd35e15a464894ac66945847d0c
Reviewed-on: https://go-review.googlesource.com/27437
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-08-21 16:49:48 +00:00
Matthew Dempsky
70544c91ff cmd/compile/internal/syntax: match old parser errors and line numbers
This makes a bunch of changes to package syntax to tweak line numbers
for AST nodes. For example, short variable declaration statements are
now associated with the location of the ":=" token, and function calls
are associated with the location of the final ")" token. These help
satisfy many unit tests that assume the old parser's behavior.

Because many of these changes are questionable, they're guarded behind
a new "gcCompat" const to make them easy to identify and revisit in
the future.

A handful of remaining tests are too difficult to make behave
identically. These have been updated to execute with -newparser=0 and
comments explaining why they need to be fixed.

all.bash now passes with both the old and new parsers.

Change-Id: Iab834b71ca8698d39269f261eb5c92a0d55a3bf4
Reviewed-on: https://go-review.googlesource.com/27199
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
2016-08-19 01:10:21 +00:00
David Chase
5b9ff11c3d cmd/compile: ppc64le working, not optimized enough
This time with the cherry-pick from the proper patch of
the old CL.

Stack size increased.
Corrected NaN-comparison glitches.
Marked g register as clobbered by calls.
Fixed shared libraries.

live_ssa.go still disabled because of differences.
Presumably turning on more optimization will fix
both the stack size and the live_ssa.go glitches.

Enhanced debugging output for shared libs test.

Rebased onto master.

Updates #16010.

Change-Id: I40864faf1ef32c118fb141b7ef8e854498e6b2c4
Reviewed-on: https://go-review.googlesource.com/27159
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2016-08-18 16:34:47 +00:00
Cherry Zhang
3d5cf72ca9 cmd/compile: CSE copied tuple selectors
In CSE if a tuple generator is CSE'd to a different block, its
selectors are copied to the same block. In this case, also CES
the copied selectors.

Test copied from Keith's CL 27202.

Fixes #16741.

Change-Id: I2fc8b9513d430f10d6104275cfff5fb75d3ef3d9
Reviewed-on: https://go-review.googlesource.com/27236
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
Reviewed-by: Keith Randall <khr@golang.org>
2016-08-17 21:03:26 +00:00
Cherry Zhang
04e76f295f test: add test for CL 26831
Test nil check removal for access of PAUTOHEAP.

Change-Id: Id739a9cda7cd3ff173bdcccfedcad93ee90711ef
Reviewed-on: https://go-review.googlesource.com/27232
Run-TryBot: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-08-17 14:50:34 +00:00
Josh Bleecher Snyder
615a52b95b cmd/compile: inline x, ok := y.(T) where T is a scalar
When T is a scalar, there are no runtime calls
required, which makes this a clear win.

encoding/binary:
WriteInts-8                958ns ± 3%     864ns ± 2%   -9.80%  (p=0.000 n=15+15)

This also considerably shrinks a core fmt
routine:

Before: "".(*pp).printArg t=1 size=3952 args=0x20 locals=0xf0
After:  "".(*pp).printArg t=1 size=2624 args=0x20 locals=0x98

Unfortunately, I find it very hard to get stable
numbers out of the fmt benchmarks due to thermal scaling.

Change-Id: I1278006b030253bf8e48dc7631d18985cdaa143d
Reviewed-on: https://go-review.googlesource.com/26659
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Keith Randall <khr@golang.org>
2016-08-17 01:12:01 +00:00
Keith Randall
a16a189fb9 test: remove unused variable
ssaMain is no longer needed.

Change-Id: I0b77f0bcd482329d73018bd80a6e068e622e191b
Reviewed-on: https://go-review.googlesource.com/27190
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-08-16 21:46:54 +00:00
Keith Randall
64214792e2 cmd/compile: allow unsafe.Pointer(nil) as static data
Fixes #16306

Change-Id: If8e2f411fe9a5a5c198f10765fee7261ba8feaf2
Reviewed-on: https://go-review.googlesource.com/24836
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
2016-08-16 17:47:50 +00:00
Robert Griesemer
c7b9bd7456 cmd/compile: don't crash when exporting self-recursive interfaces
For #16369.

Change-Id: I4c9f5a66b95558adcc1bcface164b9b2b4382d2f
Reviewed-on: https://go-review.googlesource.com/24979
Reviewed-by: Alan Donovan <adonovan@google.com>
2016-08-16 17:07:03 +00:00
Keith Randall
d251030fa6 cmd/compile: don't fold >32bit constants into a MULQ
Don't fold constant factors into a multiply
beyond the capacity of a MULQ instruction (32 bits).

Fixes #16733

Change-Id: Idc213c6cb06f7c94008a8cf9e60a9e77d085fd89
Reviewed-on: https://go-review.googlesource.com/27160
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-08-16 16:46:48 +00:00
Cherry Zhang
d99cee79b9 [dev.ssa] cmd/compile, etc.: more ARM64 optimizations, and enable SSA by default
Add more ARM64 optimizations:
- use hardware zero register when it is possible.
- use shifted ops.
  The assembler supports shifted ops but not documented, nor knows
  how to print it. This CL adds them.
- enable fast division.
  This was disabled because it makes the old backend generate slower
  code. But with SSA it generates faster code.

Turn on SSA by default, also adjust tests.

Change-Id: I7794479954c83bb65008dcb457bc1e21d7496da6
Reviewed-on: https://go-review.googlesource.com/26950
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
2016-08-15 03:37:34 +00:00
Keith Randall
c069bc4996 [dev.ssa] cmd/compile: implement GO386=387
Last part of the 386 SSA port.

Modify the x86 backend to simulate SSE registers and
instructions with 387 registers and instructions.
The simulation isn't terribly performant, but it works,
and the old implementation wasn't very performant either.
Leaving to people who care about 387 to optimize if they want.

Turn on SSA backend for 386 by default.

Fixes #16358

Change-Id: I678fb59132620b2c47e993c1c10c4c21135f70c0
Reviewed-on: https://go-review.googlesource.com/25271
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2016-08-10 17:41:01 +00:00
Keith Randall
69a755b602 [dev.ssa] cmd/compile: port SSA backend to amd64p32
It's not a new backend, just a PtrSize==4 modification
of the existing AMD64 backend.

Change-Id: Icc63521a5cf4ebb379f7430ef3f070894c09afda
Reviewed-on: https://go-review.googlesource.com/25586
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
2016-08-09 15:48:26 +00:00
Keith Randall
d2286ea284 [dev.ssa] Merge remote-tracking branch 'origin/master' into mergebranch
Semi-regular merge from tip into dev.ssa.

Change-Id: Iadb60e594ef65a99c0e1404b14205fa67c32a9e9
2016-08-04 10:08:20 -07:00
Cherry Zhang
111d590f86 cmd/compile: fix possible spill of invalid pointer with DUFFZERO on AMD64
SSA compiler on AMD64 may spill Duff-adjusted address as scalar. If
the object is on stack and the stack moves, the spilled address become
invalid.

Making the spill pointer-typed does not work. The Duff-adjusted address
points to the memory before the area to be zeroed and may be invalid.
This may cause stack scanning code panic.

Fix it by doing Duff-adjustment in genValue, so the intermediate value
is not seen by the reg allocator, and will not be spilled.

Add a test to cover both cases. As it depends on allocation, it may
be not always triggered.

Fixes #16515.

Change-Id: Ia81d60204782de7405b7046165ad063384ede0db
Reviewed-on: https://go-review.googlesource.com/25309
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
2016-07-29 01:09:55 +00:00
Cherry Zhang
6b6de15d32 [dev.ssa] cmd/compile: support NaCl in SSA for ARM
NaCl code runs in sandbox and there are restrictions for its
instruction uses
(https://developer.chrome.com/native-client/reference/sandbox_internals/arm-32-bit-sandbox).

Like the legacy backend, on NaCl,
- don't use R9, which is used as NaCl's "thread pointer".
- don't use Duff's device.
- don't use indexed load/stores.
- the assembler rewrites DIV/MOD to runtime calls, which on NaCl
  clobbers R12, so R12 is marked as clobbered for DIV/MOD.
- other restrictions are satisfied by the assembler.

Enable SSA specific tests on nacl/arm, and disable non-SSA ones.

Updates #15365.

Change-Id: I9262693ec6756b89ca29d3ae4e52a96fe5403b02
Reviewed-on: https://go-review.googlesource.com/24859
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
2016-07-16 03:13:45 +00:00
Keith Randall
efefd11725 [dev.ssa] Merge remote-tracking branch 'origin/master' into mergebranch
Semi-regular merge of tip into dev.ssa.

Change-Id: I855817c4746237792a2dab6eaf471087a3646be4
2016-07-13 11:12:44 -07:00
Ian Lance Taylor
bbe5da4260 cmd/compile, syscall: add //go:uintptrescapes comment, and use it
This new comment can be used to declare that the uintptr arguments to a
function may be converted from pointers, and that those pointers should
be considered to escape. This is used for the Call methods in
dll_windows.go that take uintptr arguments, because they call Syscall.

We can't treat these functions as we do syscall.Syscall, because unlike
Syscall they may cause the stack to grow. For Syscall we can assume that
stack arguments can remain on the stack, but for these functions we need
them to escape.

Fixes #16035.

Change-Id: Ia0e5b4068c04f8d303d95ab9ea394939f1f57454
Reviewed-on: https://go-review.googlesource.com/24551
Reviewed-by: David Chase <drchase@google.com>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-07-06 20:48:41 +00:00
Cherry Zhang
42181ad852 [dev.ssa] cmd/compile: enable SSA on ARM by default
As Josh mentioned in CL 24716, there has been requests for using SSA
for ARM. SSA can still be disabled by setting -ssa=0 for cmd/compile,
or partially enabled with GOSSAFUNC, GOSSAPKG, and GOSSAHASH.

Not enable SSA by default on NaCl, which is not supported yet.

Enable SSA-specific tests on ARM: live_ssa.go and nilptr3_ssa.go;
disable non-SSA tests: live.go, nilptr3.go, and slicepot.go.

Updates #15365.

Change-Id: Ic2ca8d166aeca8517b9d262a55e92f2130683a16
Reviewed-on: https://go-review.googlesource.com/23953
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: David Chase <drchase@google.com>
2016-07-06 15:05:50 +00:00
Ian Lance Taylor
519b469795 cmd/compile: mark live heap-allocated pparamout vars as needzero
If we don't mark them as needzero, we have a live pointer variable
containing possible garbage, which will baffle the GC.

Fixes #16249.

Change-Id: I7c423ceaca199ddd46fc2c23e5965e7973f07584
Reviewed-on: https://go-review.googlesource.com/24715
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2016-07-02 00:40:40 +00:00
Konstantin Shaposhnikov
85a4f44745 cmd/vet: make checking example names in _test packages more robust
Prior to this change package "foo" had to be installed in order to check
example names in "foo_test" package.

However by the time "foo_test" package is checked a parsed "foo" package
has been already constructed. Use it to check example names.

Also change TestDivergentPackagesExamples test to pass directory of the
package to the vet tool as it is the most common way to invoke it. This
requires changes to errchk to add support for grabbing source files from
a directory.

Fixes #16189

Change-Id: Ief103d07b024822282b86c24250835cc591793e8
Reviewed-on: https://go-review.googlesource.com/24488
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-06-28 22:09:00 +00:00
Ian Lance Taylor
e0f986bf26 cmd/compile: avoid function literal name collision with "glob"
The compiler was treating all global function literals as occurring in a
function named "glob", which caused a symbol name collision when there
was an actual function named "glob".  Fixed by adding a period.

Fixes #16193.

Change-Id: I67792901a8ca04635ba41d172bfaee99944f594d
Reviewed-on: https://go-review.googlesource.com/24500
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
2016-06-27 21:05:28 +00:00
Keith Randall
6effdd28de cmd/compile: keep heap pointer for escaping output parameters live
Make sure the pointer to the heap copy of an output parameter is kept
live throughout the function.  The function could panic at any point,
and then a defer could recover.  Thus, we need the pointer to the heap
copy always available so the post-deferreturn code can copy the return
value back to the stack.

Before this CL, the pointer to the heap copy could be considered dead in
certain situations, like code which is reverse dominated by a panic call.

Fixes #16095.

Change-Id: Ic3800423e563670e5b567b473bf4c84cddb49a4c
Reviewed-on: https://go-review.googlesource.com/24213
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
2016-06-27 16:48:48 +00:00
Robert Griesemer
1f446432dd cmd/compile: fix error msg mentioning different packages with same name
This is a regression from 1.6. The respective code in importimport
(export.go) was not exactly replicated with the new importer. Also
copied over the missing cyclic import check.

Added test cases.

Fixes #16133.

Change-Id: I1e0a39ff1275ca62a8054874294d400ed83fb26a
Reviewed-on: https://go-review.googlesource.com/24312
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Robert Griesemer <gri@golang.org>
2016-06-22 00:12:55 +00:00
Robert Griesemer
845992eeed test: add -s flag to commands understood by run.go
If -s is specified, each file is considered a separate
package even if multiple files have the same package names.

For instance, the action and flag "errorcheckdir -s"
will compile all files in the respective directory as
individual packages.

Change-Id: Ic5c2f9e915a669433f66c2d3fe0ac068227a502f
Reviewed-on: https://go-review.googlesource.com/24313
Run-TryBot: Robert Griesemer <gri@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-06-22 00:06:19 +00:00
Ian Lance Taylor
09834d1c08 runtime: panic with the right error on iface conversion
A straight conversion from a type T to an interface type I, where T does
not implement I, should always panic with an interface conversion error
that shows the missing method.  This was not happening if the conversion
was done once using the comma-ok form (the result would not be OK) and
then again in a straight conversion.  Due to an error in the runtime
package the second conversion was failing with a nil pointer
dereference.

Fixes #16130.

Change-Id: I8b9fca0f1bb635a6181b8b76de8c2385bb7ac2d2
Reviewed-on: https://go-review.googlesource.com/24284
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Michel Lespinasse <walken@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Andrew Gerrand <adg@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2016-06-21 01:43:42 +00:00
Ian Lance Taylor
e1a6e71e74 test: add missing copyright notice
Change-Id: I2a5353203ca2958fa37fc7a5ea3f22ad4fc62b0e
Reviewed-on: https://go-review.googlesource.com/24282
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
2016-06-20 23:46:33 +00:00
David Crawshaw
af0fc83985 cmd/compile, etc: handle many struct fields
This adds 8 bytes of binary size to every type that has methods. It is
the smallest change I could come up with for 1.7.

Fixes #16037

Change-Id: Ibe15c3165854a21768596967757864b880dbfeed
Reviewed-on: https://go-review.googlesource.com/24070
Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-06-14 15:32:34 +00:00
David Chase
595426c0d9 cmd/compile: fix OASWB rewriting in racewalk
Special case for rewriting OAS inits omitted OASWB, added
that and OAS2FUNC.  The special case cannot be default case,
that causes racewalk to fail in horrible ways.

Fixes #16008.

Change-Id: Ie0d2f5735fe9d8255a109597b36d196d4f86703a
Reviewed-on: https://go-review.googlesource.com/23954
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-06-12 23:58:25 +00:00
Keith Randall
e3f1c66f31 cmd/compile: for tail calls in stubs, ensure args are alive
The generated code for interface stubs sometimes just messes
with a few of the args and then tail-calls to the target routine.
The args that aren't explicitly modified appear to not be used.
But they are used, by the thing we're tail calling.

Fixes #16016

Change-Id: Ib9b3a8311bb714a201daee002885fcb59e0463fa
Reviewed-on: https://go-review.googlesource.com/23960
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
2016-06-09 19:32:51 +00:00
Cherry Zhang
f3689d1382 cmd/compile: nilcheck interface value in go/defer interface call for SSA
This matches the behavior of the legacy backend.

Fixes #15975 (if this is the intended behavior)

Change-Id: Id277959069b8b8bf9958fa8f2cbc762c752a1a19
Reviewed-on: https://go-review.googlesource.com/23820
Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-06-08 20:35:53 +00:00
Keith Randall
afad74ec30 cmd/compile: cgen_append can handle complex targets
Post-liveness fix, the slices on both sides can now be
indirects of & variables.  The cgen code handles those
cases just fine.

Fixes #15988

Change-Id: I378ad1d5121587e6107a9879c167291a70bbb9e4
Reviewed-on: https://go-review.googlesource.com/23863
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
2016-06-08 00:01:09 +00:00
Keith Randall
2f088884ae cmd/compile: use fake package for allocating autos
Make sure auto names don't conflict with function names. Before this CL,
we confused name a.len (the len field of the slice a) with a.len (the function
len declared on a).

Fixes #15961

Change-Id: I14913de697b521fb35db9a1b10ba201f25d552bb
Reviewed-on: https://go-review.googlesource.com/23789
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-06-07 06:04:23 +00:00
Ian Lance Taylor
6901b08482 cmd/link: avoid name collision with DWARF .def suffix
Adding a .def suffix for DWARF info collided with the DWARF info,
without the suffix, for a method named def. Change the suffix to ..def
instead.

Fixes #15926.

Change-Id: If1bf1bcb5dff1d7f7b79f78e3f7a3bbfcd2201bb
Reviewed-on: https://go-review.googlesource.com/23733
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
2016-06-03 16:56:29 +00:00
Robert Griesemer
bbd1dcdf7d cmd/compile: correctly export underlying type of predecl. error type
Fixes #15920.

Change-Id: I78cd79b91a58d0f7218b80f9445417f4ee071a6e
Reviewed-on: https://go-review.googlesource.com/23606
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-06-01 21:32:46 +00:00
Keith Randall
52fe472472 cmd/compile: for arm, zero unaligned memory 1 byte at a time
If memory might be unaligned, zero it one byte at a time
instead of 4 bytes at a time.

Fixes #15902

Change-Id: I4eff0840e042e2f137c1a4028f08793eb7dfd703
Reviewed-on: https://go-review.googlesource.com/23587
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Minux Ma <minux@golang.org>
2016-06-01 14:14:13 +00:00
Josh Bleecher Snyder
8003e79154 test: add more switch error handling tests
Some of these errors are reported in the wrong places.
That’s issue #15911 and #15912.

Change-Id: Ia09d7f89be4d15f05217a542a61b6ac08090dd87
Reviewed-on: https://go-review.googlesource.com/23588
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-05-31 22:29:36 +00:00
Josh Bleecher Snyder
0e13dbc1a9 cmd/compile: disallow multiple nil cases in a type switch
Fixes #15898.

Change-Id: I66e2ad21f283563c7142aa820f0354711d964768
Reviewed-on: https://go-review.googlesource.com/23573
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Keith Randall <khr@golang.org>
2016-05-31 20:31:00 +00:00
Russ Cox
b6dc3e6f66 cmd/compile: fix liveness computation for heap-escaped parameters
The liveness computation of parameters generally was never
correct, but forcing all parameters to be live throughout the
function covered up that problem. The new SSA back end is
too clever: even though it currently keeps the parameter values live
throughout the function, it may find optimizations that mean
the current values are not written back to the original parameter
stack slots immediately or ever (for example if a parameter is set
to nil, SSA constant propagation may replace all later uses of the
parameter with a constant nil, eliminating the need to write the nil
value back to the stack slot), so the liveness code must now
track the actual operations on the stack slots, exposing these
problems.

One small problem in the handling of arguments is that nodarg
can return ONAME PPARAM nodes with adjusted offsets, so that
there are actually multiple *Node pointers for the same parameter
in the instruction stream. This might be possible to correct, but
not in this CL. For now, we fix this by using n.Orig instead of n
when considering PPARAM and PPARAMOUT nodes.

The major problem in the handling of arguments is general
confusion in the liveness code about the meaning of PPARAM|PHEAP
and PPARAMOUT|PHEAP nodes, especially as contrasted with PAUTO|PHEAP.
The difference between these two is that when a local variable "moves"
to the heap, it's really just allocated there to start with; in contrast,
when an argument moves to the heap, the actual data has to be copied
there from the stack at the beginning of the function, and when a
result "moves" to the heap the value in the heap has to be copied
back to the stack when the function returns
This general confusion is also present in the SSA back end.

The PHEAP bit worked decently when I first introduced it 7 years ago (!)
in 391425ae. The back end did nothing sophisticated, and in particular
there was no analysis at all: no escape analysis, no liveness analysis,
and certainly no SSA back end. But the complications caused in the
various downstream consumers suggest that this should be a detail
kept mainly in the front end.

This CL therefore eliminates both the PHEAP bit and even the idea of
"heap variables" from the back ends.

First, it replaces the PPARAM|PHEAP, PPARAMOUT|PHEAP, and PAUTO|PHEAP
variable classes with the single PAUTOHEAP, a pseudo-class indicating
a variable maintained on the heap and available by indirecting a
local variable kept on the stack (a plain PAUTO).

Second, walkexpr replaces all references to PAUTOHEAP variables
with indirections of the corresponding PAUTO variable.
The back ends and the liveness code now just see plain indirected
variables. This may actually produce better code, but the real goal
here is to eliminate these little-used and somewhat suspect code
paths in the back end analyses.

The OPARAM node type goes away too.

A followup CL will do the same to PPARAMREF. I'm not sure that
the back ends (SSA in particular) are handling those right either,
and with the framework established in this CL that change is trivial
and the result clearly more correct.

Fixes #15747.

Change-Id: I2770b1ce3cbc93981bfc7166be66a9da12013d74
Reviewed-on: https://go-review.googlesource.com/23393
Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-05-27 03:19:52 +00:00
Robert Griesemer
30282b091d cmd/compile: correctly import labels, gotos, and fallthroughs
The importer had several bugs with respect to labels and gotos:
- it didn't create a new ONAME node for label names (label dcl,
  goto, continue, and break)
- it overwrote the symbol for gotos with the dclstack
- it didn't set the dclstack for labels

In the process changed export format slightly to always assume
a label name for labels and gotos, and never assume a label for
fallthroughs.

For fallthroughs and switch cases, now also set Xoffset like in
the parser. (Not setting it, i.e., using 0 was ok since this is
only used for verifying correct use of fallthroughs, which was
checked already. But it's an extra level of verification of the
import.)

Fixes #15838.

Change-Id: I3637f6314b8651c918df0c8cd70cd858c92bd483
Reviewed-on: https://go-review.googlesource.com/23445
Run-TryBot: Robert Griesemer <gri@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-05-26 00:32:03 +00:00
Russ Cox
85e3c9e6b8 cmd/compile, go/types: omit needless word in error message
CL 21462 and CL 21463 made this message say explicitly that the problem
was a struct field in a map, but the word "directly" is unnecessary,
sounds wrong, and makes the error long.

Change-Id: I2fb68cdaeb8bd94776b8022cf3eae751919ccf6f
Reviewed-on: https://go-review.googlesource.com/23373
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: David Chase <drchase@google.com>
2016-05-24 15:07:16 +00:00
Robert Griesemer
448246adff cmd/compile: don't exit early because of hidden error messages
Non-syntax errors are always counted to determine if to exit
early, but then deduplication eliminates them. This can lead
to situations which report "too many errors" and only one
error is shown.

De-duplicate non-syntax errors early, at least the ones that
appear consecutively, and only count the ones actually being
shown. This doesn't work perfectly as they may not appear in
sequence, but it's cheap and good enough.

Fixes #14136.

Change-Id: I7b11ebb2e1e082f0d604b88e544fe5ba967af1d7
Reviewed-on: https://go-review.googlesource.com/23259
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2016-05-19 23:17:54 +00:00
Keith Randall
d603c27c6b cmd/compile: large ptr literals must escape
They get rewritten to NEWs, and they must be marked as escaping
so walk doesn't try to allocate them back onto the stack.

Fixes #15733

Change-Id: I433033e737c3de51a9e83a5a273168dbc9110b74
Reviewed-on: https://go-review.googlesource.com/23223
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
2016-05-19 15:12:01 +00:00
Keith Randall
075880a8e8 cmd/compile: fix build
Run live vars test only on ssa builds.
We can't just drop KeepAlive ops during regalloc.  We need
to replace them with copies.

Change-Id: Ib4b3b1381415db88fdc2165fc0a9541b73ad9759
Reviewed-on: https://go-review.googlesource.com/23225
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2016-05-18 20:44:00 +00:00
Keith Randall
3572c6418b cmd/compile: keep pointer input arguments live throughout function
Introduce a KeepAlive op which makes sure that its argument is kept
live until the KeepAlive.  Use KeepAlive to mark pointer input
arguments as live after each function call and at each return.

We do this change only for pointer arguments.  Those are the
critical ones to handle because they might have finalizers.
Doing compound arguments (slices, structs, ...) is more complicated
because we would need to track field liveness individually (we do
that for auto variables now, but inputs requires extra trickery).

Turn off the automatic marking of args as live.  That way, when args
are explicitly nulled, plive will know that the original argument is
dead.

The KeepAlive op will be the eventual implementation of
runtime.KeepAlive.

Fixes #15277

Change-Id: I5f223e65d99c9f8342c03fbb1512c4d363e903e5
Reviewed-on: https://go-review.googlesource.com/22365
Reviewed-by: David Chase <drchase@google.com>
Reviewed-by: Russ Cox <rsc@golang.org>
2016-05-18 19:25:27 +00:00
Matthew Dempsky
c65647d620 cmd/compile: handle unsafe.Pointer(f()) correctly
Previously statements like

    f(unsafe.Pointer(g()), int(h()))

would be reordered into a sequence of statements like

    autotmp_g := g()
    autotmp_h := h()
    f(unsafe.Pointer(autotmp_g), int(autotmp_h))

which can leave g's temporary value on the stack as a uintptr, rather
than an unsafe.Pointer. Instead, recognize uintptr-to-unsafe.Pointer
conversions when reordering function calls to instead produce:

    autotmp_g := unsafe.Pointer(g())
    autotmp_h := h()
    f(autotmp_g, int(autotmp_h))

Fixes #15329.

Change-Id: I2cdbd89d233d0d5c94791513a9fd5fd958d11ed5
Reviewed-on: https://go-review.googlesource.com/22273
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2016-05-18 14:01:22 +00:00
Robert Griesemer
aff4889089 cmd/compile: clean up encoding of method expressions and add test
Fixes #15646.

Change-Id: Ic13d1adc0a358149209195cdb03811eeee506fb8
Reviewed-on: https://go-review.googlesource.com/23052
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2016-05-11 19:23:04 +00:00
Keith Randall
9e96ad851d test: add test for unlowered ITab
See #15604.  This was a bug in a CL that has since been
rolled back.  Adding a test to challenge the next attempter.

Change-Id: Ic43be254ea6eaab0071018cdc61d9b1c21f19cbf
Reviewed-on: https://go-review.googlesource.com/23000
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2016-05-10 16:30:34 +00:00
David Chase
3c09001917 cmd/compile: correct sparseSet probes in regalloc to avoid index error
In regalloc, a sparse map is preallocated for later use by
spill-in-loop sinking.  However, variables (spills) are added
during register allocation before spill sinking, and a map
query involving any of these new variables will index out of
bounds in the map.

To fix:
1) fix the queries to use s.orig[v.ID].ID instead, to ensure
proper indexing.  Note that s.orig will be nil for values
that are not eligible for spilling (like memory and flags).

2) add a test.

Fixes #15585.

Change-Id: I8f2caa93b132a0f2a9161d2178320d5550583075
Reviewed-on: https://go-review.googlesource.com/22911
Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-05-09 18:35:44 +00:00
Russ Cox
feb6131b1a cmd/compile: add -linkobj flag to allow writing object file in two parts
This flag is experimental and the semantics may change
even after Go 1.7 is released. There are no changes to code
not using the flag.

The first part is for reading by future compiles.
The second part is for reading by the final link step.
Splitting the file this way allows distributed build systems
to ship the compile-input part only to compile steps and
the linker-input part only to linker steps.

The first part is basically just the export data,
and the second part is basically everything else.
The overall files still have the same broad structure,
so that existing tools will work with both halves.
It's just that various pieces are empty in the two halves.

This also copies the two bits of data the linker needed from
export data into the object header proper, so that the linker
doesn't need any export data at all. That eliminates a TODO
that was left for switching to the binary export data.
(Now the linker doesn't need to know about the switch.)

The default is still to write out a combined output file.
Nothing changes unless you pass -linkobj to the compiler.
There is no support in the go command for -linkobj,
since the go command doesn't copy objects around.
The expectation is that other build systems (like bazel, say)
might take advantage of this.

The header adjustment and the option for the split output
was intended as part of the zip archives, but the zip archives
have been cut from Go 1.7. Doing this to the current archives
both unblocks one step in the switch to binary export data
and enables alternate build systems to experiment with the
new flag using the Go 1.7 release.

Change-Id: I8b6eab25b8a22b0a266ba0ac6d31e594f3d117f3
Reviewed-on: https://go-review.googlesource.com/22500
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
2016-05-09 17:31:45 +00:00
Robert Griesemer
87a2ae1fa2 cmd/compile: fix binary export of composite literals with implicit types
Also:
- replaced remaining panics with Fatal calls
- more comments

Fixes #15572.

Change-Id: Ifb27e80b66700f5692a84078764a1e928d4b310d
Reviewed-on: https://go-review.googlesource.com/22935
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2016-05-09 06:16:07 +00:00
Josh Bleecher Snyder
3696e469e5 test: add test for issue 15602
The problem was fixed by the rollback in CL 22930.
This CL just adds a test to prevent regressions.

Fixes #15602

Change-Id: I37453f6e18ca43081266fe7f154c6d63fbaffd9b
Reviewed-on: https://go-review.googlesource.com/22931
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2016-05-08 22:59:43 +00:00
Matthew Dempsky
55546efeee Revert "cmd/compile: properly handle map assignments for OAS2DOTTYPE"
This reverts commit 9d7c9b4384.

For #15602.

Change-Id: I464184b05babe4cb8dedab6161efa730cea6ee2d
Reviewed-on: https://go-review.googlesource.com/22930
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-05-08 20:15:04 +00:00
Robert Griesemer
394ac818b0 cmd/compile: add and enable (internal) option to only track named types
The new export format keeps track of all types that are exported.
If a type is seen that was exported before, only a reference to
that type is emitted. The importer maintains a list of all the
seen types and uses that list to resolve type references.

The existing compiler infrastructure's invariants assumes that
only named types are referred to before they are fully set up.
Referring to unnamed incomplete types causes problems. One of
the issues was #15548.

Added a new internal flag 'trackAllTypes' to enable/disable
this type tracking. With this change only named types are
tracked.

Verified that this fix also addresses #15548, even w/o the
prior fix for that issue (in fact that prior fix is turned
off if trackAllTypes is disabled because it's not needed).

The test for #15548 covers also this change.

For #15548.

Change-Id: Id0b3ff983629703d025a442823f99649fd728a56
Reviewed-on: https://go-review.googlesource.com/22839
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2016-05-07 23:56:02 +00:00
Tal Shprecher
9d7c9b4384 cmd/compile: properly handle map assignments for OAS2DOTTYPE
The boolean destination in an OAS2DOTTYPE expression craps out during
compilation when trying to assign to a map entry because, unlike slice entries,
map entries are not directly addressable in memory. The solution is to
properly order the boolean destination node so that map entries are set
via autotmp variables.

Fixes #14678

Change-Id: If344e8f232b5bdac1b53c0f0d21eeb43ab17d3de
Reviewed-on: https://go-review.googlesource.com/22833
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-05-07 08:00:39 +00:00
Robert Griesemer
d68f800620 test: update test for issue 15548
Accidentally checked in the version of file c.go that doesn't
exhibit the bug - hence the test was not testing the bug fix.
Double-checked that this version exposes the bug w/o the fix.

Change-Id: Ie4dc455229d1ac802a80164b5d549c2ad4d971f5
Reviewed-on: https://go-review.googlesource.com/22837
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Minux Ma <minux@golang.org>
2016-05-06 02:50:42 +00:00
Robert Griesemer
8650c23034 cmd/compile: verify imported types after they are fully imported
Fixes #15548.

Change-Id: I1dfa9c8739a4b6d5e4c737c1a1e09e80e045b7aa
Reviewed-on: https://go-review.googlesource.com/22803
Reviewed-by: Alan Donovan <adonovan@google.com>
2016-05-05 20:31:30 +00:00
Cherry Zhang
04a30025db test: enable fixedbugs/issue10607.go test on linux/mips64x
external linking is now supported.

Change-Id: I13e90c39dad86e60781adecdbe8e6bc9e522f740
Reviewed-on: https://go-review.googlesource.com/19811
Reviewed-by: Minux Ma <minux@golang.org>
2016-05-04 16:42:08 +00:00
Emmanuel Odeke
53fd522c0d all: make copyright headers consistent with one space after period
Follows suit with https://go-review.googlesource.com/#/c/20111.

Generated by running
$ grep -R 'Go Authors.  All' * | cut -d":" -f1 | while read F;do perl -pi -e 's/Go
Authors.  All/Go Authors. All/g' $F;done

The code in cmd/internal/unvendor wasn't changed.

Fixes #15213

Change-Id: I4f235cee0a62ec435f9e8540a1ec08ae03b1a75f
Reviewed-on: https://go-review.googlesource.com/21819
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-05-02 13:43:18 +00:00
David Chase
d8d33514f9 cmd/compile: Move divconst_test out of test/bench/go1
This is necessary to avoid disrupting the go1 suite and gives
us a place to put other tests of basic compiler function and
correctness.

Change-Id: I36933819ff2bfe6a2121fff2be9a98efd2123d9a
Reviewed-on: https://go-review.googlesource.com/22597
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2016-04-29 16:20:18 +00:00
Robert Griesemer
d954f9c4d1 test: added test case for (fixed) issue 15470
Follow-up to https://golang.org/cl/22543.

Change-Id: I873b4fa6616ac2aea8faada2fccd126233bbc07f
Reviewed-on: https://go-review.googlesource.com/22583
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2016-04-29 00:42:13 +00:00
Austin Clements
b49b71ae19 runtime: don't rescan globals
Currently the runtime rescans globals during mark 2 and mark
termination. This costs as much as 500µs/MB in STW time, which is
enough to surpass the 10ms STW limit with only 20MB of globals.

It's also basically unnecessary. The compiler already generates write
barriers for global -> heap pointer updates and the regular write
barrier doesn't check whether the slot is a global or in the heap.
Some less common write barriers do cause problems.
heapBitsBulkBarrier, which is used by typedmemmove and related
functions, currently depends on having access to the pointer bitmap
and as a result ignores writes to globals. Likewise, the
reflect-related write barriers reflect_typedmemmovepartial and
callwritebarrier ignore non-heap destinations; though it appears they
can never be called with global pointers anyway.

This commit makes heapBitsBulkBarrier issue write barriers for writes
to global pointers using the data and BSS pointer bitmaps, removes the
inheap checks from the reflection write barriers, and eliminates the
rescans during mark 2 and mark termination. It also adds a test that
writes to globals have write barriers.

Programs with large data+BSS segments (with pointers) aren't common,
but for programs that do have large data+BSS segments, this
significantly reduces pause time:

name \ 95%ile-time/markTerm              old         new  delta
LargeBSS/bss:1GB/gomaxprocs:4  148200µs ± 6%  302µs ±52%  -99.80% (p=0.008 n=5+5)

This very slightly improves the go1 benchmarks:

name                      old time/op    new time/op    delta
BinaryTree17-12              2.62s ± 3%     2.62s ± 4%    ~     (p=0.904 n=20+20)
Fannkuch11-12                2.15s ± 1%     2.13s ± 0%  -1.29%  (p=0.000 n=18+20)
FmtFprintfEmpty-12          48.3ns ± 2%    47.6ns ± 1%  -1.52%  (p=0.000 n=20+16)
FmtFprintfString-12          152ns ± 0%     152ns ± 1%    ~     (p=0.725 n=18+18)
FmtFprintfInt-12             150ns ± 1%     149ns ± 1%  -1.14%  (p=0.000 n=19+20)
FmtFprintfIntInt-12          250ns ± 0%     244ns ± 1%  -2.12%  (p=0.000 n=20+18)
FmtFprintfPrefixedInt-12     219ns ± 1%     217ns ± 1%  -1.20%  (p=0.000 n=19+20)
FmtFprintfFloat-12           280ns ± 0%     281ns ± 1%  +0.47%  (p=0.000 n=19+19)
FmtManyArgs-12               928ns ± 0%     923ns ± 1%  -0.53%  (p=0.000 n=19+18)
GobDecode-12                7.21ms ± 1%    7.24ms ± 2%    ~     (p=0.091 n=19+19)
GobEncode-12                6.07ms ± 1%    6.05ms ± 1%  -0.36%  (p=0.002 n=20+17)
Gzip-12                      265ms ± 1%     265ms ± 1%    ~     (p=0.496 n=20+19)
Gunzip-12                   39.6ms ± 1%    39.3ms ± 1%  -0.85%  (p=0.000 n=19+19)
HTTPClientServer-12         74.0µs ± 2%    73.8µs ± 1%    ~     (p=0.569 n=20+19)
JSONEncode-12               15.4ms ± 1%    15.3ms ± 1%  -0.25%  (p=0.049 n=17+17)
JSONDecode-12               53.7ms ± 2%    53.0ms ± 1%  -1.29%  (p=0.000 n=18+17)
Mandelbrot200-12            3.97ms ± 1%    3.97ms ± 0%    ~     (p=0.072 n=17+18)
GoParse-12                  3.35ms ± 2%    3.36ms ± 1%  +0.51%  (p=0.005 n=18+20)
RegexpMatchEasy0_32-12      72.7ns ± 2%    72.2ns ± 1%  -0.70%  (p=0.005 n=19+19)
RegexpMatchEasy0_1K-12       246ns ± 1%     245ns ± 0%  -0.60%  (p=0.000 n=18+16)
RegexpMatchEasy1_32-12      72.8ns ± 1%    72.5ns ± 1%  -0.37%  (p=0.011 n=18+18)
RegexpMatchEasy1_1K-12       380ns ± 1%     385ns ± 1%  +1.34%  (p=0.000 n=20+19)
RegexpMatchMedium_32-12      115ns ± 2%     115ns ± 1%  +0.44%  (p=0.047 n=20+20)
RegexpMatchMedium_1K-12     35.4µs ± 1%    35.5µs ± 1%    ~     (p=0.079 n=18+19)
RegexpMatchHard_32-12       1.83µs ± 0%    1.80µs ± 1%  -1.76%  (p=0.000 n=18+18)
RegexpMatchHard_1K-12       55.1µs ± 0%    54.3µs ± 1%  -1.42%  (p=0.000 n=18+19)
Revcomp-12                   386ms ± 1%     381ms ± 1%  -1.14%  (p=0.000 n=18+18)
Template-12                 61.5ms ± 2%    61.5ms ± 2%    ~     (p=0.647 n=19+20)
TimeParse-12                 338ns ± 0%     336ns ± 1%  -0.72%  (p=0.000 n=14+19)
TimeFormat-12                350ns ± 0%     357ns ± 0%  +2.05%  (p=0.000 n=19+18)
[Geo mean]                  55.3µs         55.0µs       -0.41%

Change-Id: I57e8720385a1b991aeebd111b6874354308e2a6b
Reviewed-on: https://go-review.googlesource.com/20829
Run-TryBot: Austin Clements <austin@google.com>
Reviewed-by: Rick Hudson <rlh@golang.org>
2016-04-27 18:48:16 +00:00
Zhongwei Yao
74a9bad638 cmd/compile: enable const division for arm64
performance:
benchmark                   old ns/op     new ns/op     delta
BenchmarkDivconstI64-8      8.28          2.70          -67.39%
BenchmarkDivconstU64-8      8.28          4.69          -43.36%
BenchmarkDivconstI32-8      8.28          6.39          -22.83%
BenchmarkDivconstU32-8      8.28          4.43          -46.50%
BenchmarkDivconstI16-8      5.17          5.17          +0.00%
BenchmarkDivconstU16-8      5.33          5.34          +0.19%
BenchmarkDivconstI8-8       3.50          3.50          +0.00%
BenchmarkDivconstU8-8       3.51          3.50          -0.28%

Fixes #15382

Change-Id: Ibce7b28f0586d593b33c4d4ecc5d5e7e7c905d13
Reviewed-on: https://go-review.googlesource.com/22292
Reviewed-by: Michael Munday <munday@ca.ibm.com>
Reviewed-by: David Chase <drchase@google.com>
2016-04-27 17:47:49 +00:00
Matthew Dempsky
e48a2958d1 cmd/compile: treat empty and absent struct field tags as identical
Fixes #15439.

Change-Id: I5a32384c46e20f8db6968e5a9e854c45ab262fe4
Reviewed-on: https://go-review.googlesource.com/22429
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-04-25 21:28:45 +00:00
Alexandru Moșoi
8b92397bcd cmd/compile: introduce bool operations.
Introduce OrB, EqB, NeqB, AndB to handle bool operations.

Change-Id: I53e4d5125a8090d5eeb4576db619103f19fff58d
Reviewed-on: https://go-review.googlesource.com/22412
Reviewed-by: Keith Randall <khr@golang.org>
2016-04-25 20:43:04 +00:00
Josh Bleecher Snyder
9dcbc43f4f test: add test for issue 15084
The underlying issues have been fixed.
All the individual fixes have their own tests,
but it's still useful to have a plain source test.

Fixes #15084

Change-Id: I06c485a7d0716201bd57d1f3be53668dddd7ec14
Reviewed-on: https://go-review.googlesource.com/22426
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
2016-04-25 19:20:40 +00:00
Josh Bleecher Snyder
3de87bc4d9 test: add test that required algs get generated
This is a follow-up to CLs 19769 and 19770.

Change-Id: Ia9b71055613b80df4ce62b34fcc4f479f04f72fd
Reviewed-on: https://go-review.googlesource.com/22399
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
2016-04-24 21:36:52 +00:00
Keith Randall
934c359964 cmd/compile: reorder how slicelit initializes a slice
func f(x, y, z *int) {
    a := []*int{x,y,z}
    ...
  }

We used to use:
  var tmp [3]*int
  a := tmp[:]
  a[0] = x
  a[1] = y
  a[2] = z

Now we do:
  var tmp [3]*int
  tmp[0] = x
  tmp[1] = y
  tmp[2] = z
  a := tmp[:]

Doesn't sound like a big deal, but the compiler has trouble
eliminating write barriers when using the former method because it
doesn't know that the slice points to the stack.  In the latter
method, the compiler knows the array is on the stack and as a result
doesn't emit any write barriers.

This turns out to be extremely common when building ... args, like
for calls fmt.Printf.

Makes go binaries ~1% smaller.

Doesn't have a measurable effect on the go1 fmt benchmarks,
unfortunately.

Fixes #14263
Update #6853

Change-Id: I9074a2788ec9e561a75f3b71c119b69f304d6ba2
Reviewed-on: https://go-review.googlesource.com/22395
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
2016-04-24 18:15:41 +00:00
Alexandru Moșoi
caef4496fc cmd/compile: convert some Phis into And8.
See discussion at [1]. True value must have a fixed non-zero
representation meaning that a && b can be implemented as a & b.

[1] https://groups.google.com/forum/#!topic/golang-dev/xV0vPuFP9Vg

This change helps with m := a && b, but it's more common to see
if a && b { do something } which is not handled.

Change-Id: Ib6f9ff898a0a8c05d12466e2464e4fe781035394
Reviewed-on: https://go-review.googlesource.com/22313
Run-TryBot: Alexandru Moșoi <alexandru@mosoi.ro>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2016-04-22 17:22:03 +00:00
Keith Randall
3c1a4c1902 cmd/compile: don't nilcheck newobject and return values from mapaccess{1,2}
They are guaranteed to be non-nil, no point in inserting
nil checks for them.

Fixes #15390

Change-Id: I3b9a0f2319affc2139dcc446d0a56c6785ae5a86
Reviewed-on: https://go-review.googlesource.com/22291
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
2016-04-22 16:18:42 +00:00
Tal Shprecher
75b886ab79 cmd/compile: reject embedded unsafe.Pointer values
Fixes #14729

Change-Id: Ied819aa7b23e25de30aa8cde049c97297b4cab11
Reviewed-on: https://go-review.googlesource.com/22325
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-04-21 00:32:01 +00:00
David Crawshaw
7acb642e4f test: print output on link -X failure
(Split out from CL 22205.)

Change-Id: Iab66ac2a1cd3716966d8e59c570931bce95aba9b
Reviewed-on: https://go-review.googlesource.com/22297
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2016-04-20 17:37:35 +00:00
Alexandru Moșoi
8b20fd000d cmd/compile: transform some Phis into Or8.
func f(a, b bool) bool {
          return a || b
}

is now a single instructions (excluding loading and unloading the arguments):
      v10 = ORB <bool> v11 v12 : AX

Change-Id: Iff63399410cb46909f4318ea1c3f45a029f4aa5e
Reviewed-on: https://go-review.googlesource.com/21872
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
2016-04-19 22:04:30 +00:00
Ian Lance Taylor
f5423a63df cmd/compile: a dot expression can not be a struct literal key
Passes toolstash -cmp.

Fixes #15311.

Change-Id: I1d67f5c9de38e899ab2d6c8986fabd6f197df23a
Reviewed-on: https://go-review.googlesource.com/22162
Reviewed-by: David Crawshaw <crawshaw@golang.org>
2016-04-18 15:09:47 +00:00
Keith Randall
ac8127d7e6 cmd/compile: fix register size for ODOTPTR result
The result of ODOTPTR, as well as a bunch of other ops,
should be the type of the result, not always a pointer type.

This fixes an amd64p32 bug where we were incorrectly truncating
a 64-bit slice index to 32 bits, and then barfing on a weird
load-64-bits-but-then-truncate-to-32-bits op that doesn't exist.

Fixes #15252

Change-Id: Ie62f4315fffd79f233e5449324ccc0879f5ac343
Reviewed-on: https://go-review.googlesource.com/22094
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-04-14 21:19:12 +00:00
Josh Bleecher Snyder
644493f109 cmd/compile: clear hidden value at end of channel range body
While we’re here, clean up a few comments.

Fixes #15281

Change-Id: Ia6173e9941133db08f57bc80bdd3c5722122bfdb
Reviewed-on: https://go-review.googlesource.com/22082
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
2016-04-14 19:20:26 +00:00
Michael Munday
24bd465bca test: use correct value in error message in init1.go
Print numGC followed by numGC1, rather than printing numGC twice.

Change-Id: I8e7144b6a11d4ae9be0d82d88b86fed04b906e2f
Reviewed-on: https://go-review.googlesource.com/22087
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2016-04-14 18:35:09 +00:00
Tal Shprecher
24967ec122 cmd/compile: make enqueued map keys fail validation on forward types
Map keys are currently validated in multiple locations but share
a common validation routine. The problem is that early validations
should be lenient enough to allow for forward types while the final
validations should not. The final validations should fail on forward
types since they've already settled.

This change also separates the key type checking from the creation
of the map via typMap. Instead of the mapqueue being populated in
copytype() by checking the map line number, it's populated in the
same block that validates the key type. This isolates key validation
logic while type checking.

Fixes #14988

Change-Id: Ia47cf6213585d6c63b3a35249104c0439feae658
Reviewed-on: https://go-review.googlesource.com/21830
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-04-13 08:43:12 +00:00
Matthew Dempsky
0e01db4b8d cmd/compile: fix crash on bare package name in constant declarations
Fixes #11361.

Change-Id: I70b8808f97f0e07de680e7e6ede1322ea0fdbbc0
Reviewed-on: https://go-review.googlesource.com/21936
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2016-04-13 06:37:39 +00:00
Alexandru Moșoi
6c6089b3fd cmd/compile: bce when max and limit are consts
Removes 49 more bound checks in make.bash. For example:

var a[100]int
for i := 0; i < 50; i++ {
  use a[i+25]
}

Change-Id: I85e0130ee5d07f0ece9b17044bba1a2047414ce7
Reviewed-on: https://go-review.googlesource.com/21379
Reviewed-by: David Chase <drchase@google.com>
Run-TryBot: Alexandru Moșoi <alexandru@mosoi.ro>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-04-11 16:01:22 +00:00
David Chase
c3b3e7b4ef cmd/compile: insert instrumentation more carefully in racewalk
Be more careful about inserting instrumentation in racewalk.
If the node being instrumented is an OAS, and it has a non-
empty Ninit, then append instrumentation to the Ninit list
rather than letting it be inserted before the OAS (and the
compilation of its init list).  This deals with the case that
the Ninit list defines a variable used in the RHS of the OAS.

Fixes #15091.

Change-Id: Iac91696d9104d07f0bf1bd3499bbf56b2e1ef073
Reviewed-on: https://go-review.googlesource.com/21771
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
Run-TryBot: David Chase <drchase@google.com>
2016-04-08 21:06:39 +00:00
Michael Munday
dae98d5c3b test: skip nilptr3 test on s390x
Fails for the same reason as ppc64 and mips64 (incomplete
optimization).

Change-Id: Ieb4d997fc27d4f2b756e63dd7f588abe10c0213a
Reviewed-on: https://go-review.googlesource.com/20963
Reviewed-by: Bill O'Farrell <billotosyr@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2016-04-08 17:51:46 +00:00
Keith Randall
68ac1f7746 cmd/compile: Fix constant-folding of unsigned shifts
Make sure the results of unsigned constant-folded
shifts are sign-extended into the AuxInt field.

Fixes #15175

Change-Id: I3490d1bc3d9b2e1578ed30964645508577894f58
Reviewed-on: https://go-review.googlesource.com/21586
Reviewed-by: Alexandru Moșoi <alexandru@mosoi.ro>
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-04-07 21:39:32 +00:00
Alexandru Moșoi
8448d3aace cmd/compile: fold CMPconst and SHR
Fold the comparison when the SHR result is small.

Useful for:
- murmur mix like hashing where higher bits are desirable, i.e. hash = uint32(i * C) >> 18
- integer log2 via DeBruijn sequence: http://graphics.stanford.edu/~seander/bithacks.html#IntegerLogDeBruijn

Change-Id: If70ae18cb86f4cc83ab6213f88ced03cc4986156
Reviewed-on: https://go-review.googlesource.com/21514
Run-TryBot: Alexandru Moșoi <alexandru@mosoi.ro>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
2016-04-07 13:28:13 +00:00
Richard Miller
a25e368f44 test: make goprint.go wait for goroutine termination
Test goprint.go sometimes failed on a slow builder (plan9_arm)
because of timing dependency.  Instead of sleeping for a fixed
time to allow the child goroutine to finish, wait explicitly for
child termination by calling runtime.NumGoroutine until the
returned value is 1.

Fixes #15097

Change-Id: Ib3ef5ec3c8277083c774542f48bcd4ff2f79efde
Reviewed-on: https://go-review.googlesource.com/21603
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
2016-04-06 18:45:00 +00:00
Keith Randall
309144b7f1 cmd/compile: fix x=x assignments
No point in doing anything for x=x assignments.
In addition, skipping these assignments prevents generating:
    VARDEF x
    COPY x -> x
which is bad because x is incorrectly considered
dead before the vardef.

Fixes #14904

Change-Id: I6817055ec20bcc34a9648617e0439505ee355f82
Reviewed-on: https://go-review.googlesource.com/21470
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Dave Cheney <dave@cheney.net>
2016-04-06 15:04:32 +00:00
David Chase
d8c815d8b5 cmd/compile: note escape of parts of closured-capture vars
Missed a case for closure calls (OCALLFUNC && indirect) in
esc.go:esccall.

Cleanup to runtime code for windows to more thoroughly hide
a technical escape.  Also made code pickier about failing
to late non-optional kernel32.dll.

Fixes #14409.

Change-Id: Ie75486a2c8626c4583224e02e4872c2875f7bca5
Reviewed-on: https://go-review.googlesource.com/20102
Run-TryBot: David Chase <drchase@google.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2016-04-05 18:10:09 +00:00
Alexandru Moșoi
1747788c56 cmd/compile: add a pass to print bound checks
Since BCE happens over several passes (opt, loopbce, prove)
it's easy to regress especially with rewriting.

The pass is only activated with special debug flag.

Change-Id: I46205982e7a2751156db8e875d69af6138068f59
Reviewed-on: https://go-review.googlesource.com/21510
Run-TryBot: Alexandru Moșoi <alexandru@mosoi.ro>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
2016-04-05 12:46:59 +00:00
Caio Marcelo de Oliveira Filho
f229e46783 cmd/compile: better error when assigning to struct field in map
Identify this assignment case and instead of the more general error

    prog.go:6: cannot assign to students["sally"].age

produce

    prog.go:6: cannot directly assign to struct field students["sally"].age in map

that explains why the assignment is not possible.

Fixes #13779.

Change-Id: I90c10b445f907834fc1735aa66e44a0f447aa74f
Reviewed-on: https://go-review.googlesource.com/21462
Reviewed-by: David Chase <drchase@google.com>
2016-04-04 14:07:47 +00:00
Eric Engestrom
7a8caf7d43 all: fix spelling mistakes
Signed-off-by: Eric Engestrom <eric@engestrom.ch>

Change-Id: I91873aaebf79bdf1c00d38aacc1a1fb8d79656a7
Reviewed-on: https://go-review.googlesource.com/21433
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-04-03 17:03:15 +00:00
Alexandru Moșoi
27ebc84716 cmd/compile: handle non-negatives in prove
Handle this case:
if 0 <= i && i < len(a) {
        use a[i]
}

Shaves about 5k from pkg/tools/linux_amd64/*.

Change-Id: I6675ff49aa306b0d241b074c5738e448204cd981
Reviewed-on: https://go-review.googlesource.com/21431
Run-TryBot: Alexandru Moșoi <alexandru@mosoi.ro>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2016-04-02 20:34:38 +00:00
Todd Neal
ac8d97b679 cmd/compile: fix inlining of switch issue
The issue was seen when inlining an exported function that contained
a fallthrough statement.

Fixes #15071

Change-Id: I1e8215ad49d57673dba7e8f8bd2ed8ad290dc452
Reviewed-on: https://go-review.googlesource.com/21452
Reviewed-by: Dave Cheney <dave@cheney.net>
2016-04-02 12:38:00 +00:00
Alexandru Moșoi
b91cc53033 cmd/compile/internal/ssa: BCE for induction variables
There are 5293 loop in the main go repository.
A survey of the top most common for loops:

     18 for __k__ := 0; i < len(sa.Addr); i++ {
     19 for __k__ := 0; ; i++ {
     19 for __k__ := 0; i < 16; i++ {
     25 for __k__ := 0; i < length; i++ {
     30 for __k__ := 0; i < 8; i++ {
     49 for __k__ := 0; i < len(s); i++ {
     67 for __k__ := 0; i < n; i++ {
    376 for __k__ := range __slice__ {
    685 for __k__, __v__ := range __slice__ {
   2074 for __, __v__ := range __slice__ {

The algorithm to find induction variables handles all cases
with an upper limit. It currently doesn't find related induction
variables such as c * ind or c + ind.

842 out of 22954 bound checks are removed for src/make.bash.
1957 out of 42952 bounds checks are removed for src/all.bash.

Things to do in follow-up CLs:
* Find the associated pointer for `for _, v := range a {}`
* Drop the NilChecks on the pointer.
* Replace the implicit induction variable by a loop over the pointer

Generated garbage can be reduced if we share the sdom between passes.

% benchstat old.txt new.txt
name       old time/op     new time/op     delta
Template       337ms ± 3%      333ms ± 3%    ~             (p=0.258 n=9+9)
GoTypes        1.11s ± 2%      1.10s ± 2%    ~           (p=0.912 n=10+10)
Compiler       5.25s ± 1%      5.29s ± 2%    ~             (p=0.077 n=9+9)
MakeBash       33.5s ± 1%      34.1s ± 2%  +1.85%          (p=0.011 n=9+9)

name       old alloc/op    new alloc/op    delta
Template      63.6MB ± 0%     63.9MB ± 0%  +0.52%         (p=0.000 n=10+9)
GoTypes        218MB ± 0%      219MB ± 0%  +0.59%         (p=0.000 n=10+9)
Compiler       978MB ± 0%      985MB ± 0%  +0.69%        (p=0.000 n=10+10)

name       old allocs/op   new allocs/op   delta
Template        582k ± 0%       583k ± 0%  +0.10%        (p=0.000 n=10+10)
GoTypes        1.78M ± 0%      1.78M ± 0%  +0.12%        (p=0.000 n=10+10)
Compiler       7.68M ± 0%      7.69M ± 0%  +0.05%        (p=0.000 n=10+10)

name       old text-bytes  new text-bytes  delta
HelloSize       581k ± 0%       581k ± 0%  -0.08%        (p=0.000 n=10+10)
CmdGoSize      6.40M ± 0%      6.39M ± 0%  -0.08%        (p=0.000 n=10+10)

name       old data-bytes  new data-bytes  delta
HelloSize      3.66k ± 0%      3.66k ± 0%    ~     (all samples are equal)
CmdGoSize       134k ± 0%       134k ± 0%    ~     (all samples are equal)

name       old bss-bytes   new bss-bytes   delta
HelloSize       126k ± 0%       126k ± 0%    ~     (all samples are equal)
CmdGoSize       149k ± 0%       149k ± 0%    ~     (all samples are equal)

name       old exe-bytes   new exe-bytes   delta
HelloSize       947k ± 0%       946k ± 0%  -0.01%        (p=0.000 n=10+10)
CmdGoSize      9.92M ± 0%      9.91M ± 0%  -0.06%        (p=0.000 n=10+10)

Change-Id: Ie74bdff46fd602db41bb457333d3a762a0c3dc4d
Reviewed-on: https://go-review.googlesource.com/20517
Reviewed-by: David Chase <drchase@google.com>
Run-TryBot: Alexandru Moșoi <alexandru@mosoi.ro>
2016-04-01 09:37:58 +00:00
David Chase
b64f549ba9 cmd/compile: ignore OXXX nodes in closure captured vars list
Added a debug flag "-d closure" to explain compilation of
closures (should this be done some other way? Should we
rewrite the "-m" flag to "-d escapes"?)  Used this to
discover that cause was an OXXX node in the captured vars
list, and in turn noticed that OXXX nodes are explicitly
ignored in all other processing of captured variables.

Couldn't figure out a reproducer, did verify that this OXXX
was not caused by an unnamed return value (which is one use
of these).  Verified lack of heap allocation by examining -S
output.

Assembly:
(runtime/mgc.go:1371) PCDATA $0, $2
(runtime/mgc.go:1371) CALL "".notewakeup(SB)
(runtime/mgc.go:1377) LEAQ "".gcBgMarkWorker.func1·f(SB), AX
(runtime/mgc.go:1404) MOVQ AX, (SP)
(runtime/mgc.go:1404) MOVQ "".autotmp_2242+88(SP), CX
(runtime/mgc.go:1404) MOVQ CX, 8(SP)
(runtime/mgc.go:1404) LEAQ go.string."GC worker (idle)"(SB), AX
(runtime/mgc.go:1404) MOVQ AX, 16(SP)
(runtime/mgc.go:1404) MOVQ $16, 24(SP)
(runtime/mgc.go:1404) MOVB $20, 32(SP)
(runtime/mgc.go:1404) MOVQ $0, 40(SP)
(runtime/mgc.go:1404) PCDATA $0, $2
(runtime/mgc.go:1404) CALL "".gopark(SB)

Added a check for compiling_runtime to ensure that this is
caught in the future.  Added a test to test the check.
Verified that 1.5.3 did NOT reject the test case when
compiled with -+ flag, so this is not a recently added bug.

Cause of bug is two-part -- there was no leaking closure
detection ever, and instead it relied on capture-of-variables
to trigger compiling_runtime test, but closures improved in
1.5.3 so that mere capture of a value did not also capture
the variable, which thus allowed closures to escape, as well
as this case where the escape was spurious.  In
fixedbugs/issue14999.go, compare messages for f and g;
1.5.3 would reject g, but not f.  1.4 rejects both because
1.4 heap-allocates parameter x for both.

Fixes #14999.

Change-Id: I40bcdd27056810628e96763a44f2acddd503aee1
Reviewed-on: https://go-review.googlesource.com/21322
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2016-04-01 02:08:56 +00:00
Ian Lance Taylor
92bb694a49 cmd/compile: s.f aliases itself
The change in 20907 fixed varexpr but broke aliased.  After that change,
a reference to a field in a struct would not be seen as aliasing itself.
Before that change, it would, but only because all fields in a struct
aliased everything.

This CL changes the compiler to consider all references to a field as
aliasing all other fields in that struct.  This is imperfect--a
reference to one field does not alias another field--but is a simple fix
for the immediate problem.  A better fix would require tracking the
specific fields as well.

Fixes #15042.

Change-Id: I5c95c0dd7b0699e53022fce9bae2e8f50d6d1d04
Reviewed-on: https://go-review.googlesource.com/21390
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2016-04-01 00:47:56 +00:00
Keith Randall
4a7aba775d cmd/compile: better job of naming compound types
Compound AUTO types weren't named previously.  That was because live
variable analysis (plive.go) doesn't handle spilling to compound types.
It can't handle them because there is no valid place to put VARDEFs when
regalloc is spilling compound types.

compound types = multiword builtin types: complex, string, slice, and
interface.

Instead, we split named AUTOs into individual one-word variables.  For
example, a string s gets split into a byte ptr s.ptr and an integer
s.len.  Those two variables can be spilled to / restored from
independently.  As a result, live variable analysis can handle them
because they are one-word objects.

This CL will change how AUTOs are described in DWARF information.
Consider the code:

func f(s string, i int) int {
    x := s[i:i+5]
    g()
    return lookup(x)
}

The old compiler would spill x to two consecutive slots on the stack,
both named x (at offsets 0 and 8).  The new compiler spills the pointer
of x to a slot named x.ptr.  It doesn't spill x.len at all, as it is a
constant (5) and can be rematerialized for the call to lookup.

So compound objects may not be spilled in their entirety, and even if
they are they won't necessarily be contiguous.  Such is the price of
optimization.

Re-enable live variable analysis tests.  One test remains disabled, it
fails because of #14904.

Change-Id: I8ef2b5ab91e43a0d2136bfc231c05d100ec0b801
Reviewed-on: https://go-review.googlesource.com/21233
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
2016-03-31 22:18:26 +00:00
Keith Randall
47c9e139ae cmd/compile: extend prove pass to handle constant comparisons
Find comparisons to constants and propagate that information
down the dominator tree.  Use it to resolve other constant
comparisons on the same variable.

So if we know x >= 7, then a x > 4 condition must return true.

This change allows us to use "_ = b[7]" hints to eliminate bounds checks.

Fixes #14900

Change-Id: Idbf230bd5b7da43de3ecb48706e21cf01bf812f7
Reviewed-on: https://go-review.googlesource.com/21008
Reviewed-by: Alexandru Moșoi <alexandru@mosoi.ro>
2016-03-31 21:16:23 +00:00
Keith Randall
4b95575bd4 cmd/compile: fix build
Pushed from an old client by mistake.  These are the
missing changes.

Change-Id: Ia8d61c5c0bde907369366ea9ea98711823342803
Reviewed-on: https://go-review.googlesource.com/21349
Reviewed-by: Todd Neal <todd@tneal.org>
2016-03-31 18:00:36 +00:00
Keith Randall
b81f2f106f cmd/compile: place combined loads at the location of the last byte load
We need to make sure all the bounds checks pass before issuing
a load which combines several others.  We do this by issuing the
combined load at the last load's block, where "last" = closest to
the leaf of the dominator tree.

Fixes #15002

Change-Id: I7358116db1e039a072c12c0a73d861f3815d72af
Reviewed-on: https://go-review.googlesource.com/21246
Reviewed-by: Todd Neal <todd@tneal.org>
2016-03-31 17:21:33 +00:00
Matthew Dempsky
e6066711a0 cmd/compile, runtime: fix pedantic int->string conversions
Previously, cmd/compile rejected constant int->string conversions if
the integer value did not fit into an "int" value. Also, runtime
incorrectly truncated 64-bit values to 32-bit before checking if
they're a valid Unicode code point. According to the Go spec, both of
these cases should instead yield "\uFFFD".

Fixes #15039.

Change-Id: I3c8a3ad9a0780c0a8dc1911386a523800fec9764
Reviewed-on: https://go-review.googlesource.com/21344
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2016-03-31 10:28:23 +00:00
Brad Fitzpatrick
758447cdc9 test/fixedbugs: add test for divide by zero being optimized away
This only tests amd64 because it's currently broken on non-SSA
backends.

Fixes #8613

Change-Id: I6bc501c81c395e533bb9c7335789750e0c6b7a8f
Reviewed-on: https://go-review.googlesource.com/21325
Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-03-31 06:12:38 +00:00
Alexandru Moșoi
d8f1f8d856 cmd/compile: generalize strength reduction of mulq
* This is an improved version of an earlier patch.
* Verified with gcc up to 100.
* Limited to two instructions based on costs from
https://gmplib.org/~tege/x86-timing.pdf

Change-Id: Ib7c37de6fd8e0ba554459b15c7409508cbcf6728
Reviewed-on: https://go-review.googlesource.com/21103
Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: Alexandru Moșoi <alexandru@mosoi.ro>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-03-30 22:27:13 +00:00
Ian Lance Taylor
777a77b4d2 cmd/compile: don't skip PPARAMOUT in esccall after varargs
Fixes bug I introduced in CL 21202.

Fixes #15013.

Change-Id: I2344d7e22b8273425a0a56f4a77588b5c6e4d8c6
Reviewed-on: https://go-review.googlesource.com/21270
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2016-03-30 02:43:08 +00:00
David Chase
8eec2bbfbc cmd/compile: added some intrinsics to SSA back end
One intrinsic was needed to help get the very best
performance out of a future GC; as long as that one was
being added, I also added Bswap since that is sometimes
a handy thing to have.  I had intended to fill out the
bit-scan intrinsic family, but the mismatch between the
"scan forward" instruction and "count leading zeroes"
was large enough to cause me to leave it out -- it poses
a dilemma that I'd rather dodge right now.

These intrinsics are not exposed for general use.
That's a separate issue requiring an API proposal change
( https://github.com/golang/proposal )

All intrinsics are tested, both that they are substituted
on the appropriate architecture, and that they produce the
expected result.

Change-Id: I5848037cfd97de4f75bdc33bdd89bba00af4a8ee
Reviewed-on: https://go-review.googlesource.com/20564
Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-03-28 16:29:59 +00:00
Robert Griesemer
c12e1b0b2e cmd/compile: update vendored math/big to latest version
This makes the rounding bug fix in math/big for issue 14651 available
to the compiler.

- changes to cmd/compile/internal/big fully automatic via script
- added test case for issue
- updated old test case with correct test data

Fixes #14651.

Change-Id: Iea37a2cd8d3a75f8c96193748b66156a987bbe40
Reviewed-on: https://go-review.googlesource.com/20818
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2016-03-22 17:09:29 +00:00
Keith Randall
d4663e1353 cmd/compile: don't write back unchanged slice results
Don't write back parts of a slicing operation if they
are unchanged from the source of the slice.  For example:

x.s = x.s[0:5]         // don't write back pointer or cap
x.s = x.s[:5]          // don't write back pointer or cap
x.s = x.s[:5:7]        // don't write back pointer

There is more to be done here, for example:

x.s = x.s[:len(x.s):7] // don't write back ptr or len

This CL can't handle that one yet.

Fixes #14855

Change-Id: Id1e1a4fa7f3076dc1a76924a7f1cd791b81909bb
Reviewed-on: https://go-review.googlesource.com/20954
Reviewed-by: Austin Clements <austin@google.com>
Run-TryBot: Keith Randall <khr@golang.org>
2016-03-21 23:40:18 +00:00
Todd Neal
e41f527f4d cmd/compile: allow inlining of functions with switch statements
Allow inlining of functions with switch statements as long as they don't
contain a break or type switch.

Fixes #13071

Change-Id: I057be351ea4584def1a744ee87eafa5df47a7f6d
Reviewed-on: https://go-review.googlesource.com/20824
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2016-03-21 23:05:10 +00:00
Michael Munday
4402ee9fa3 test: add s390x case to nosplit test
Fixes this test on s390x.

Change-Id: Ie5b70e8191169867765ec9248d827ca12c6405f4
Reviewed-on: https://go-review.googlesource.com/20964
Reviewed-by: Minux Ma <minux@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-03-21 08:14:51 +00:00
Michael Munday
1a82946ea5 test/fixedbugs: add s390x case to issue11656
An instruction consisting of all 0s causes an illegal instruction
signal on s390x. Since 0s are the default in this test this CL just
makes it explicit.

Change-Id: Id6e060eed1a588f4b10a4e4861709fcd19b434ac
Reviewed-on: https://go-review.googlesource.com/20962
Reviewed-by: Minux Ma <minux@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-03-21 07:09:36 +00:00
Todd Neal
fc6bcdee79 cmd/compile: allow inlining of functions that declare a const
Consider functions with an ODCLCONST for inlining and modify exprfmt to
ignore those nodes when exporting. Don't add symbols to the export list
if there is no definition.  This occurs when OLITERAL symbols are looked
up via Pkglookup for non-exported symbols.

Fixes #7655

Change-Id: I1de827850f4c69e58107447314fe7433e378e069
Reviewed-on: https://go-review.googlesource.com/20773
Run-TryBot: Todd Neal <todd@tneal.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
2016-03-18 23:26:36 +00:00
Marcel van Lohuizen
5c83e651ad testing: prepare for the introduction of Run methods
The biggest change is that each test is now responsible for managing
the starting and stopping of its parallel subtests.

The "Main" test could be run as a tRunner as well. This shows that
the introduction of subtests is merely a generalization of and
consistent with the current semantics.

Change-Id: Ibf8388c08f85d4b2c0df69c069326762ed36a72e
Reviewed-on: https://go-review.googlesource.com/18893
Reviewed-by: Russ Cox <rsc@golang.org>
2016-03-18 11:25:54 +00:00
Keith Randall
15ed37d7b7 cmd/compile: enforce nowritebarrier in SSA compiler
Make sure we don't generate write barriers in runtime
code that is marked to forbid write barriers.

Implement the optimization that if we're writing a sliced
slice back to the location it came from, we don't need a
write barrier.

Fixes #14784

Change-Id: I04b6a3b2ac303c19817e932a36a3b006de103aaa
Reviewed-on: https://go-review.googlesource.com/20791
Reviewed-by: Austin Clements <austin@google.com>
2016-03-17 20:13:24 +00:00
David Chase
2d56dee61b cmd/compile: escape analysis explanations added to -m -m output
This should probably be considered "experimental" at this stage, but
what it needs is feedback from adventurous adopters.  I think the data
structure used for describing escape reasons might be extendable to
allow a cleanup of the underlying algorithms, which suffers from
insufficiently separated concerns (the graph does not deal well with
escape level adjustments, so it is augmented by a second custom-walk
portion of the "flood" phase. It would be better to put it all,
including level adjustments, in a single graph structure, and then
simply flood the graph.

Tweaked to avoid allocations in the no-logging case.

Modified run.go to ignore lines with leading "#" in the output (since
it can never match a line), and in -update_errors to ignore leading
tabs in output lines and to normalize embedded filenames.

Currently requires -m -m because otherwise the noise/update
burden for the other escape tests is considerable.

There is a partial test.  Existing escape analysis tests seem to
cover all except the panic case and what looks like it might be
unreachable code in escape analysis.

Fixes #10526.

Change-Id: I2524fdec54facae48b00b2548e25d9e46fcaf832
Reviewed-on: https://go-review.googlesource.com/18041
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2016-03-17 13:29:48 +00:00
Keith Randall
56e0ecc5ea cmd/compile: keep value use counts in SSA
Keep track of how many uses each Value has.  Each appearance in
Value.Args and in Block.Control counts once.

The number of uses of a value is generically useful to
constrain rewrite rules.  For instance, we might want to
prevent merging index operations into loads if the same
index expression is used lots of times.

But I have one use in particular for which the use count is required.
We must make sure we don't combine ops with loads if the load has
more than one use.  Otherwise, we may split a single load
into multiple loads and that breaks perceived behavior in
the presence of races.  In particular, the load of m.state
in sync/mutex.go:Lock can't be done twice.  (I have a separate
CL which triggers the mutex failure.  This CL has a test which
demonstrates a similar failure.)

Change-Id: Icaafa479239f48632a069d0c3f624e6ebc6b1f0e
Reviewed-on: https://go-review.googlesource.com/20790
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Todd Neal <todd@tneal.org>
2016-03-17 04:20:02 +00:00
Matthew Dempsky
b2b5e779f5 cmd/compile: ignore receiver parameters in Eqtype
Receiver parameters generally aren't relevant to the function
signature type. In particular:

  1. When checking whether a type's method implements an interface's
     method, we specifically want to ignore the receiver parameters,
     because they'll be different.

  2. When checking interface type equality, interface methods always
     use the same "fakethis" *struct{} type as their receiver.

  3. Finally, method expressions and method values degenerate into
     receiver-less function types.

The only case where we care about receiver types matching is in
addmethod, which is easily handled by adding an extra Eqtype check of
the receiver parameters. Also, added a test for this, since
(surprisingly) there weren't any.

As precedence, go/types.Identical ignores receiver parameters when
comparing go/types.Signature values.

Notably, this allows us to slightly simplify the "implements"
function, which is used for checking whether type/interface t
implements interface iface. Currently, cmd/compile actually works
around Eqtype's receiver parameter checking by creating new throwaway
TFUNC Types without the receiver parameter.

(Worse, the compiler currently only provides APIs to build TFUNC Types
from Nod syntax trees, so building those throwaway types also involves
first building throwaway syntax trees.)

Passes toolstash -cmp.

Change-Id: Ib07289c66feacee284e016bc312e8c5ff674714f
Reviewed-on: https://go-review.googlesource.com/20602
Reviewed-by: Robert Griesemer <gri@golang.org>
2016-03-17 00:38:15 +00:00
Austin Clements
3e54ca9a46 cmd/compile: omit write barrier when assigning global function
Currently we generate write barriers when the right side of an
assignment is a global function. This doesn't fall into the existing
case of storing an address of a global because we haven't lowered the
function to a pointer yet.

This write barrier is unnecessary, so eliminate it.

Fixes #13901.

Change-Id: Ibc10e00a8803db0fd75224b66ab94c3737842a79
Reviewed-on: https://go-review.googlesource.com/20772
Run-TryBot: Austin Clements <austin@google.com>
Reviewed-by: Keith Randall <khr@golang.org>
2016-03-16 22:42:45 +00:00
Robert Griesemer
bb3b10214d cmd/compile: faster parameter parsing with no OKEY nodes
Step 2 of stream-lining parameter parsing

- do parameter validity checks in parser
- two passes instead of multiple (and theoretically quadratic) passes
  when checking parameters
- removes the need for OKEY and some ONONAME nodes in those passes

This removes allocation of ~123K OKEY (incl. some ONONAME) nodes
out of a total of ~10M allocated nodes when running make.bash, or
a reduction of the number of alloacted nodes by ~1.2%.

Change-Id: I4a8ec578d0ee2a7b99892ac6b92e56f8e0415f03
Reviewed-on: https://go-review.googlesource.com/20748
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Run-TryBot: Robert Griesemer <gri@golang.org>
2016-03-16 18:54:31 +00:00
Alexandru Moșoi
cd798dcb88 cmd/compile/internal/ssa: generalize prove to all booleans
* Refacts a bit saving and restoring parents restrictions
* Shaves ~100k from pkg/tools/linux_amd64,
but most of the savings come from the rewrite rules.
* Improves on the following artificial test case:
func f1(a4 bool, a6 bool) bool {
  return a6 || (a6 || (a6 || a4)) || (a6 || (a4 || a6 || (false || a6)))
}

Change-Id: I714000f75a37a3a6617c6e6834c75bd23674215f
Reviewed-on: https://go-review.googlesource.com/20306
Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: Alexandru Moșoi <alexandru@mosoi.ro>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-03-13 12:05:41 +00:00
David Crawshaw
e2836935bb cmd/link: treat reflect.Value.Method like Call
Fixes #14740

Change-Id: Iad8d971c21977b0a1f4ef55a08bb180a8125e976
Reviewed-on: https://go-review.googlesource.com/20562
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-03-11 22:07:02 +00:00
David Crawshaw
5aa5db7593 cmd/compile: use bufio.Reader directly in lexer
Removes an intermediate layer of functions that was clogging up a
corner of the compiler's profile graph.

I can't measure a performance improvement running a large build
like jujud, but the profile reports less total time spent in
gc.(*lexer).getr.

Change-Id: I3000585cfcb0f9729d3a3859e9023690a6528591
Reviewed-on: https://go-review.googlesource.com/20565
Reviewed-by: Robert Griesemer <gri@golang.org>
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-03-11 21:27:23 +00:00
David Crawshaw
cc158403d6 cmd/compile: track reflect.Type.Method in deadcode
In addition to reflect.Value.Call, exported methods can be invoked
by the Func value in the reflect.Method struct. This CL has the
compiler track what functions get access to a legitimate reflect.Method
struct by looking for interface calls to either of:

	Method(int) reflect.Method
	MethodByName(string) (reflect.Method, bool)

This is a little overly conservative. If a user implements a type
with one of these methods without using the underlying calls on
reflect.Type, the linker will assume the worst and include all
exported methods. But it's cheap.

No change to any of the binary sizes reported in cl/20483.

For #14740

Change-Id: Ie17786395d0453ce0384d8b240ecb043b7726137
Reviewed-on: https://go-review.googlesource.com/20489
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2016-03-11 21:19:20 +00:00
Keith Randall
31d13f479a cmd/compile: don't use PPARAMOUT names for temps
The location of VARDEFs is incorrect for PPARAMOUT variables
which are also used as temporary locations.  We put in VARDEFs
when setting the variable at return time, but when the location
is also used as a temporary the lifetime values are wrong.

Fix copyelim to update the names map properly.  This is a
real name bug fix which, as a result, allows me to
write a reasonable test to trigger the PPARAMOUT bug.

This is kind of a band-aid fix for #14591.  A more pricipled
fix (which allows values to be stored in the return variable
earlier than the return point) will be harder.

Fixes #14591

Change-Id: I7df8ae103a982d1f218ed704c080d7b83cdcfdd9
Reviewed-on: https://go-review.googlesource.com/20457
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
2016-03-11 00:56:04 +00:00
Keith Randall
ddc6b64444 cmd/compile: fix defer/deferreturn
Make sure we do any just-before-return cleanup on all paths out of a
function, including when recovering.  Each exit path should include
deferreturn (if there are any defers) and then the exit
code (e.g. copying heap-escaping return values back to the stack).

Introduce a Defer SSA block type which has two outgoing edges - one the
fallthrough edge (the defer was queued successfully) and one which
immediately returns (the defer had a successful recover() call and
normal execution should resume at the return point).

Fixes #14725

Change-Id: Iad035c9fd25ef8b7a74dafbd7461cf04833d981f
Reviewed-on: https://go-review.googlesource.com/20486
Reviewed-by: David Chase <drchase@google.com>
2016-03-10 22:33:49 +00:00
Matthew Dempsky
49dad0f571 cmd/compile: support arbitrarily deep embedded fields
Fixes #13337.

Change-Id: Ie74d00390111796619150287d3f7a147750ab456
Reviewed-on: https://go-review.googlesource.com/19932
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-03-10 06:33:52 +00:00
David Chase
4c8589c328 cmd/compile: attach correct line number for fallthru-return
Fixes #14646.

Change-Id: I0bb82ed6d3533633cd8369ba37aa467948bbe155
Reviewed-on: https://go-review.googlesource.com/20381
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2016-03-08 19:23:25 +00:00
Caio Marcelo de Oliveira Filho
c97ddf9c10 cmd/compile: don't emit conversion error in non-numeric increment/decrement
In increment and decrement statements, explicit check that the type
of operand is numeric earlier. This avoids a related but less clear
error about converting "1" to be emitted.

So, when compiling

	package main

	func main() {
		var x bool
		x++
	}

instead of emitting two errors

	prog.go:5: cannot convert 1 to type bool
	prog.go:5: invalid operation: x++ (non-numeric type bool)

just emits the second error.

Fixes #12525.

Change-Id: I6e81330703765bef0d6eb6c57098c1336af7c799
Reviewed-on: https://go-review.googlesource.com/20245
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2016-03-07 14:34:58 +00:00
Matthew Dempsky
3da1a26fba cmd/compile: stop leaking 'any' type into user package
The new check corresponds to the (etype != TANY || Debug['A'] != 0)
that was lost in golang.org/cl/19936.

Fixes #14652.

Change-Id: Iec3788ff02529b3b0f0d4dd92ec9f3ef20aec849
Reviewed-on: https://go-review.googlesource.com/20271
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-03-05 02:13:04 +00:00
Rhys Hiltner
3375974e0d cmd/link/internal/ld: don't panic on short buildid
When the linker was written in C, command line arguments were passed
around as null-terminated byte arrays which encouraged checking
characters one at a time. In Go, that can easily lead to
out-of-bounds panics.

Use the more idiomatic strings.HasPrefix when checking cmd/link's -B
argument to avoid the panic, and replace the manual hex decode with
use of the encoding/hex package.

Fixes #14636

Change-Id: I45f765bbd8cf796fee1a9a3496178bf76b117827
Reviewed-on: https://go-review.googlesource.com/20211
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2016-03-04 21:20:09 +00:00
Robert Griesemer
646939c0e3 cmd/compile: re-vendor math/big to pick up bug fix
The changes to internal/big are completely automatic
by running vendor.bash in that directory.

Also added respective test case.

For #14553.

Change-Id: I98b124bcc9ad9e9bd987943719be27864423cb5d
Reviewed-on: https://go-review.googlesource.com/20199
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2016-03-04 17:40:16 +00:00
Keith Randall
9d854fd44a Merge branch 'dev.ssa' into mergebranch
Merge dev.ssa branch back into master.

Change-Id: Ie6fac3f8d355ab164f934415fe4fc7fcb8c3db16
2016-03-01 12:50:17 -08:00
David Chase
6b3462c784 [dev.ssa] cmd/compile: adjust branch likeliness for calls/loops
Static branch predictions (which guide block ordering) are
adjusted based on:

loop/not-loop     (favor looping)
abnormal-exit/not (avoid panic)
call/not-call     (avoid call)
ret/default       (treat returns as rare)

This appears to make no difference in performance of real
code, meaning the compiler itself.  The earlier version of
this has been stripped down to help make the cost of this
only-aesthetic-on-Intel phase be as cheap as possible (we
probably want information about inner loops for improving
register allocation, but because register allocation follows
close behind this pass, conceivably the information could be
reused -- so we might do this anyway just to normalize
output).

For a ./make.bash that takes 200 user seconds, about .75
second is reported in likelyadjust (summing nanoseconds
reported with -d=ssa/likelyadjust/time ).

Upstream predictions are respected.
Includes test, limited to build on amd64 only.
Did several iterations on the debugging output to allow
some rough checks on behavior.
Debug=1 logging notes agree/disagree with earlier passes,
allowing analysis like the following:

Run on make.bash:
GO_GCFLAGS=-d=ssa/likelyadjust/debug \
   ./make.bash >& lkly5.log

grep 'ranch prediction' lkly5.log | wc -l
   78242 // 78k predictions

grep 'ranch predi' lkly5.log | egrep -v 'agrees with' | wc -l
   29633 // 29k NEW predictions

grep 'disagrees' lkly5.log | wc -l
     444 // contradicted 444 times

grep '< exit' lkly5.log | wc -l
   10212 // 10k exit predictions

grep '< exit' lkly5.log | egrep 'disagrees' | wc -l
       5 // 5 contradicted by previous prediction

grep '< exit' lkly5.log | egrep -v 'agrees' | wc -l
     702 // 702-5 redundant with previous prediction

grep '< call' lkly5.log | egrep -v 'agrees' | wc -l
   16699 // 16k new call predictions

grep 'stay in loop' lkly5.log | egrep -v 'agrees' | wc -l
    3951 // 4k new "remain in loop" predictions

Fixes #11451.

Change-Id: Iafb0504f7030d304ef4b6dc1aba9a5789151a593
Reviewed-on: https://go-review.googlesource.com/19995
Run-TryBot: David Chase <drchase@google.com>
Reviewed-by: Keith Randall <khr@golang.org>
2016-03-01 20:09:41 +00:00
Alexandru Moșoi
e197f467d5 [dev.ssa] cmd/compile/internal/ssa: simplify boolean phis
* Decreases the generated code slightly.
* Similar to phiopt pass from gcc, except it only handles
booleans. Handling Eq/Neq had no impact on the generated code.

name       old time/op     new time/op     delta
Template       453ms ± 4%      451ms ± 4%    ~           (p=0.468 n=24+24)
GoTypes        1.55s ± 1%      1.55s ± 2%    ~           (p=0.287 n=24+25)
Compiler       6.53s ± 2%      6.56s ± 1%  +0.46%        (p=0.050 n=23+23)
MakeBash       45.8s ± 2%      45.7s ± 2%    ~           (p=0.866 n=24+25)

name       old text-bytes  new text-bytes  delta
HelloSize       676k ± 0%       676k ± 0%    ~     (all samples are equal)
CmdGoSize      8.07M ± 0%      8.07M ± 0%  -0.03%        (p=0.000 n=25+25)

Change-Id: Ia62477b7554127958a14cb27f85849b095d63663
Reviewed-on: https://go-review.googlesource.com/20090
Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: Alexandru Moșoi <alexandru@mosoi.ro>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-03-01 17:56:13 +00:00
Gerrit Code Review
acdb0da47d Merge "[dev.ssa] Merge remote-tracking branch 'origin/master' into ssamerge" into dev.ssa 2016-02-29 23:19:17 +00:00
Keith Randall
4fffd4569d [dev.ssa] Merge remote-tracking branch 'origin/master' into ssamerge
(Last?) Semi-regular merge from tip to dev.ssa.

Conflicts:
	src/cmd/compile/internal/gc/closure.go
	src/cmd/compile/internal/gc/gsubr.go
	src/cmd/compile/internal/gc/lex.go
	src/cmd/compile/internal/gc/pgen.go
	src/cmd/compile/internal/gc/syntax.go
	src/cmd/compile/internal/gc/walk.go
	src/cmd/internal/obj/pass.go

Change-Id: Ib5ea8bf74d420f4902a9c6208761be9f22371ae7
2016-02-29 13:32:20 -08:00
Robert Griesemer
ed1a5e5da6 cmd/compile: cleanup number lexing
Change-Id: Ib0dd458d4ab1c58a2baf36491e288ac32e2ff99e
Reviewed-on: https://go-review.googlesource.com/19962
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-02-29 19:00:10 +00:00
Alexandru Moșoi
bdea1d58cf [dev.ssa] cmd/compile/internal/ssa: remove proven redundant controls.
* It does very simple bounds checking elimination. E.g.
removes the second check in for i := range a { a[i]++; a[i++]; }
* Improves on the following redundant expression:
return a6 || (a6 || (a6 || a4)) || (a6 || (a4 || a6 || (false || a6)))
* Linear in the number of block edges.

I patched in CL 12960 that does bounds, nil and constant propagation
to make sure this CL is not just redundant. Size of pkg/tool/linux_amd64/*
(excluding compile which is affected by this change):

With IsInBounds and IsSliceInBounds
-this -12960 92285080
+this -12960 91947416
-this +12960 91978976
+this +12960 91923088

Gain is ~110% of 12960.

Without IsInBounds and IsSliceInBounds (older run)
-this -12960 95515512
+this -12960 95492536
-this +12960 95216920
+this +12960 95204440

Shaves 22k on its own.

* Can we handle IsInBounds better with this? In
for i := range a { a[i]++; } the bounds checking at a[i]
is not eliminated.

Change-Id: I98957427399145fb33693173fd4d5a8d71c7cc20
Reviewed-on: https://go-review.googlesource.com/19710
Reviewed-by: David Chase <drchase@google.com>
Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: Alexandru Moșoi <alexandru@mosoi.ro>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-02-28 19:48:20 +00:00
Matthew Dempsky
af558acc47 cmd/compile: fix contrived line number errors
If a general comment contains multiple newline characters, we can't
simply unread one and then re-lex it via the general whitespace lexing
phase, because then we'll reset lineno to the line before the "*/"
marker, rather than keeping it where we found the "/*" marker.

Also, for processing imports, call importfile before advancing the
lexer with p.next(), so that lineno reflects the line where we found
the import path, and not the token afterwards.

Fixes #14520.

Change-Id: I785a2d83d632280113d4b757de0d57c88ba2caf4
Reviewed-on: https://go-review.googlesource.com/19934
Reviewed-by: Robert Griesemer <gri@golang.org>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-02-26 21:25:43 +00:00
Keith Randall
b462744e70 [dev.ssa] test: remove extra tests from non-SSA builds
non-SSA backends are all over the map as to whether nil checks
get removed or not.  amd64, 386, 386/387, arm are all subtly different.
Remove these extra checks for now, they are in nilptr3_ssa.go so they
won't get lost.

Change-Id: I2e0051f488fb2cb7278c6fdd44cb9d68b5778345
Reviewed-on: https://go-review.googlesource.com/19961
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2016-02-26 19:07:16 +00:00
Keith Randall
4a346e7489 [dev.ssa] cmd/compile: get rid of nil checks before float loads/stores
Just like we do for integer loads/stores.

Update #14511

Change-Id: Ic6ca6b54301438a5701ea5fb0be755451cb24d45
Reviewed-on: https://go-review.googlesource.com/19923
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
Run-TryBot: Keith Randall <khr@golang.org>
2016-02-26 04:33:46 +00:00
Keith Randall
d3f15ff6bc [dev.ssa] cmd/compile: shrink stack guard
Our stack frame sizes look pretty good now.  Lower the stack
guard from 1024 to 720.
Tip is currently using 720.
We could go lower (to 640 at least) except PPC doesn't like that.

Change-Id: Ie5f96c0e822435638223f1e8a2bd1a1eed68e6aa
Reviewed-on: https://go-review.googlesource.com/19922
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
2016-02-25 22:32:48 +00:00
Robert Griesemer
539aa05a64 cmd/compile: towards simpler and faster lexing: always use getr
Always reading runes (rather than bytes) has negligible overhead
(a simple if at the moment - it can be eliminated eventually) but
simplifies the lexer logic and opens up the door for speedups.
In the process remove many int conversions that are now not needed
anymore.

Also, because identifiers are now more easily recognized, remove
talph label and move identifier lexing "in place".

Also, instead of accepting all chars < 0x80 and then check for
"frogs", only permit valid characters in the first place. Removes
an extra call for common simple tokens and leads to simpler logic.

`time go build -a net/http` (best of 5 runs) seems 1% faster.
Assuming this is in the noise, there is no noticeable performance
degradation with this change.

Change-Id: I3454c9bf8b91808188cf7a5f559341749da9a1eb
Reviewed-on: https://go-review.googlesource.com/19847
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-02-24 04:36:25 +00:00
Keith Randall
80bc512449 [dev.ssa] Merge remote-tracking branch 'origin/master' into mergebranch
Semi-regular merge from tip to dev.ssa.

Change-Id: If7d2269f267bcbc0ecd3a483d349951044470e3f
2016-02-23 14:42:20 -08:00
Robert Griesemer
d1cc7f70cd cmd/compile: give informative error instead of "stupid shift"
Fixes #13940.

Change-Id: I00fe377c949e5be4cbc035f6ca18e547e326bfba
Reviewed-on: https://go-review.googlesource.com/19856
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-02-23 22:31:35 +00:00
Matthew Dempsky
7d3a40978a cmd/compile: refactor export data parsing
Merge push_parser and pop_parser into a single parse_import function
and inline unimportfile. Shake out function boundaries a little bit so
that the symmetry is readily visible.

Move the import_package call into parse_import (and inline
import_there into import_package).  This means importfile no longer
needs to provide fake import data to be needlessly lexed/parsed every
time it's called.

Also, instead of indicating import success/failure by whether the next
token is "package", import_spec can just check whether importpkg is
non-nil.

Tangentially, this somehow alters the diagnostics produced for
test/fixedbugs/issue11610.go.  However, the new diagnostics are more
consistent with those produced when the empty import statement is
absent, which seems more desirable than maintaining the previous
errors.

Change-Id: I5cd1c22aa14da8a743ef569ff084711d137279d5
Reviewed-on: https://go-review.googlesource.com/19650
Reviewed-by: Robert Griesemer <gri@golang.org>
2016-02-20 04:31:42 +00:00
David Chase
fb2af2b35b cmd/compile: don't walk field-name syntax in esc.go
Walking the field name as if it were an expression
caused a called to haspointers with a TFIELD, which panics.
Trigger was a field at a large offset within a large struct,
combined with a struct literal expression mentioning that
field.

Fixes #14405

Change-Id: I4589badae27cf3d7cf365f3a66c13447512f41f9
Reviewed-on: https://go-review.googlesource.com/19699
Reviewed-by: Russ Cox <rsc@golang.org>
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-02-19 19:40:49 +00:00
Tal Shprecher
5c5e8d4105 cmd/compile: avoid leak of dottype expression if type does not contain pointers.
Fixes #13805

Change-Id: Ica9aae2e054b74f67d28ab27f72c52a3f03eeb59
Reviewed-on: https://go-review.googlesource.com/19489
Run-TryBot: Michael Matloob <matloob@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
2016-02-19 16:10:14 +00:00
Russ Cox
51b624e6a2 cmd/link: remove alternate -X flag spelling
The Go 1.6 release notes say we'll remove the “-X name value” form
(in favor of the “-X name=value” form) in Go 1.7.
Do that.

Also establish the doc/go1.7.txt file.

Change-Id: Ie4565a6bc5dbcf155181754d8d92bfbb23c75338
Reviewed-on: https://go-review.googlesource.com/19614
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-02-19 01:35:25 +00:00
Russ Cox
feb2a5d610 cmd/compile: print struct tags in var decl in inlined func body
This bug was introduced in golang.org/cl/18217,
while trying to fix #13777.

Originally I wanted to just disable inlining for the case
being handled incorrectly, but it's fairly difficult to detect
and much easier just to fix. Since the case being handled
incorrectly was inlined correctly in Go 1.5, not inlining it
would also be somewhat of a regression.
So just fix it.

Test case copied from Ian's CL 19520.

The mistake to worry about in this CL would be relaxing
the condition too much (we now print the note more often
than we did yesterday). To confirm that we'd catch this mistake,
I checked that changing (!fmtbody || !t.Funarg) to (true) does
cause fixedbugs/issue13777.go to fail. And putting it back
to what is written in this CL makes that test pass again
as well as the new fixedbugs/issue14331.go.
So I believe that the new condition is correct for both constraints.

Fixes #14331.

Change-Id: I91f75a4d5d07c53af5caea1855c780d9874b8df6
Reviewed-on: https://go-review.googlesource.com/19514
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-02-16 19:39:10 +00:00
Keith Randall
e3033fc535 cmd/compile: add write barrier to type switch
Type switches need write barriers if the written-to
variable is heap allocated.

For the added needwritebarrier call, the right arg doesn't
really matter, I just pass something that will never disqualify
the write barrier.  The left arg is the one that matters.

Fixes #14306

Change-Id: Ic2754167cce062064ea2eeac2944ea4f77cc9c3b
Reviewed-on: https://go-review.googlesource.com/19481
Reviewed-by: Russ Cox <rsc@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-02-12 21:07:21 +00:00
Keith Randall
eb0cff9a76 [dev.ssa] Merge remote-tracking branch 'origin/master' into mergebranch
Semi-regular merge from tip to dev.ssa.

Two fixes:
1) Mark selectgo as not returning.  This caused problems
   because there are no VARKILL ops on the selectgo path,
   causing things to be marked live that shouldn't be.
2) Tell the amd64 assembler that addressing modes like
   name(SP)(AX*4) are ok.

Change-Id: I9ca81c76391b1a65cc47edc8610c70ff1a621913
2016-02-10 09:31:41 -08:00
Robert Griesemer
d37d76af43 cmd/compile: fix parsing of inlined interface types with unexported methods
Fixes #14164.

Change-Id: Ib1d1d29674c99cf88e0ae12724823a31f5dbb95c
Reviewed-on: https://go-review.googlesource.com/19087
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2016-02-01 20:29:19 +00:00
Keith Randall
6a96a2fe5a [dev.ssa] cmd/compile: make cse faster
It is one of the slowest compiler phases right now, and we
run two of them.

Instead of using a map to make the initial partition, use a sort.
It is much less memory intensive.

Do a few optimizations to avoid work for size-1 equivalence classes.

Implement -N.

Change-Id: I1d2d85d3771abc918db4dd7cc30b0b2d854b15e1
Reviewed-on: https://go-review.googlesource.com/19024
Reviewed-by: David Chase <drchase@google.com>
2016-01-28 20:59:20 +00:00
Keith Randall
3c26c0db39 [dev.ssa] cmd/compile: short-circuit empty blocks
Empty blocks are introduced to remove critical edges.
After regalloc, we can remove any of the added blocks
that are still empty.

Change-Id: I0b40e95ac3a6cc1e632a479443479532b6c5ccd9
Reviewed-on: https://go-review.googlesource.com/18833
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
2016-01-22 22:12:12 +00:00
Robert Griesemer
5395846890 cmd/compile: don't print (empty) package name in errors referring to built-ins
Fixes #14010.

Change-Id: Idfd4b063eecf453fe00f3e798099023707a65963
Reviewed-on: https://go-review.googlesource.com/18738
Reviewed-by: Russ Cox <rsc@golang.org>
Run-TryBot: Robert Griesemer <gri@golang.org>
2016-01-20 04:43:43 +00:00
Keith Randall
23d5810c8f [dev.ssa] Merge remote-tracking branch 'origin/master' into mergebranch
Semi-regular merge from tip to dev.ssa.

Conflicts:
	src/runtime/sys_windows_amd64.s

Change-Id: I5f733130049c810e6ceacd46dad85faebca52b29
2016-01-19 14:13:16 -08:00
Robert Griesemer
7ce2402bae cmd/compile: don't crash on invalid labeled statement
Fixes #14006.

Change-Id: Ia819073677ad6993c02255e23760ee21598427b4
Reviewed-on: https://go-review.googlesource.com/18736
Run-TryBot: Robert Griesemer <gri@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-01-19 21:34:28 +00:00
Russ Cox
1ac637c766 cmd/compile: recognize Syscall-like functions for liveness analysis
Consider this code:

	func f(*int)

	func g() {
		p := new(int)
		f(p)
	}

where f is an assembly function.
In general liveness analysis assumes that during the call to f, p is dead
in this frame. If f has retained p, p will be found alive in f's frame and keep
the new(int) from being garbage collected. This is all correct and works.
We use the Go func declaration for f to give the assembly function
liveness information (the arguments are assumed live for the entire call).

Now consider this code:

	func h1() {
		p := new(int)
		syscall.Syscall(1, 2, 3, uintptr(unsafe.Pointer(p)))
	}

Here syscall.Syscall is taking the place of f, but because its arguments
are uintptr, the liveness analysis and the garbage collector ignore them.
Since p is no longer live in h once the call starts, if the garbage collector
scans the stack while the system call is blocked, it will find no reference
to the new(int) and reclaim it. If the kernel is going to write to *p once
the call finishes, reclaiming the memory is a mistake.

We can't change the arguments or the liveness information for
syscall.Syscall itself, both for compatibility and because sometimes the
arguments really are integers, and the garbage collector will get quite upset
if it finds an integer where it expects a pointer. The problem is that
these arguments are fundamentally untyped.

The solution we have taken in the syscall package's wrappers in past
releases is to insert a call to a dummy function named "use", to make
it look like the argument is live during the call to syscall.Syscall:

	func h2() {
		p := new(int)
		syscall.Syscall(1, 2, 3, uintptr(unsafe.Pointer(p)))
		use(unsafe.Pointer(p))
	}

Keeping p alive during the call means that if the garbage collector
scans the stack during the system call now, it will find the reference to p.

Unfortunately, this approach is not available to users outside syscall,
because 'use' is unexported, and people also have to realize they need
to use it and do so. There is much existing code using syscall.Syscall
without a 'use'-like function. That code will fail very occasionally in
mysterious ways (see #13372).

This CL fixes all that existing code by making the compiler do the right
thing automatically, without any code modifications. That is, it takes h1
above, which is incorrect code today, and makes it correct code.

Specifically, if the compiler sees a foreign func definition (one
without a body) that has uintptr arguments, it marks those arguments
as "unsafe uintptrs". If it later sees the function being called
with uintptr(unsafe.Pointer(x)) as an argument, it arranges to mark x
as having escaped, and it makes sure to hold x in a live temporary
variable until the call returns, so that the garbage collector cannot
reclaim whatever heap memory x points to.

For now I am leaving the explicit calls to use in package syscall,
but they can be removed early in a future cycle (likely Go 1.7).

The rule has no effect on escape analysis, only on liveness analysis.

Fixes #13372.

Change-Id: I2addb83f70d08db08c64d394f9d06ff0a063c500
Reviewed-on: https://go-review.googlesource.com/18584
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-01-14 01:16:45 +00:00
David Chase
e779bfa5d2 cmd/compile: better modeling of escape across loop levels
Brief background on "why heap allocate".  Things can be
forced to the heap for the following reasons:

1) address published, hence lifetime unknown.
2) size unknown/too large, cannot be stack allocated
3) multiplicity unknown/too large, cannot be stack allocated
4) reachable from heap (not necessarily published)

The bug here is a case of failing to enforce 4) when an
object Y was reachable from a heap allocation X forced
because of 3).  It was found in the case of a closure
allocated within a loop (X) and assigned to a variable
outside the loop (multiplicity unknown) where the closure
also captured a map (Y) declared outside the loop (reachable
from heap). Note the variable declared outside the loop (Y)
is not published, has known size, and known multiplicity
(one). The only reason for heap allocation is that it was
reached from a heap allocated item (X), but because that was
not forced by publication, it has to be tracked by loop
level, but escape-loop level was not tracked and thus a bug
results.

The fix is that when a heap allocation is newly discovered,
use its looplevel as the minimum loop level for downstream
escape flooding.

Every attempt to generalize this bug to X-in-loop-
references-Y-outside loop succeeded, so the fix was aimed
to be general.  Anywhere that loop level forces heap
allocation, the loop level is tracked.  This is not yet
tested for all possible X and Y, but it is correctness-
conservative and because it caused only one trivial
regression in the escape tests, it is probably also
performance-conservative.

The new test checks the following:
1) in the map case, that if fn escapes, so does the map.
2) in the map case, if fn does not escape, neither does the map.
3) in the &x case, that if fn escapes, so does &x.
4) in the &x case, if fn does not escape, neither does &x.

Fixes #13799.

Change-Id: Ie280bef2bb86ec869c7c206789d0b68f080c3fdb
Reviewed-on: https://go-review.googlesource.com/18234
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2016-01-13 04:01:00 +00:00
Russ Cox
20d745c57c encoding/base64: fix streaming decode of padding-free base64
Fixes #13384.

Change-Id: Id9e827acddc8de139f93c5de0c6486bc4334c7d4
Reviewed-on: https://go-review.googlesource.com/18330
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-01-08 15:07:45 +00:00
Matthew Dempsky
27691fa467 cmd/compile: recognize !typedbool is typed
Adding the evconst(n) call for OANDAND and OOROR in
golang.org/cl/18262 was originally just to parallel the above iscmp
branch, but upon further inspection it seemed odd that removing it
caused test/fixedbugs/issue6671.go's

    var b mybool
    // ...
    b = bool(true) && true // ERROR "cannot use"

to start failing (i.e., by not emitting the expected "cannot use"
error).

The problem is that evconst(n)'s settrue and setfalse paths always
reset n.Type to idealbool, even for logical operators where n.Type
should preserve the operand type.  Adding the evconst(n) call for
OANDAND/OOROR inadvertantly worked around this by turning the later
evconst(n) call at line 2167 into a noop, so the "n.Type = t"
assignment at line 739 would preserve the operand type.

However, that means evconst(n) was still clobbering n.Type for ONOT,
so declarations like:

    const _ bool = !mybool(true)

were erroneously accepted.

Update #13821.

Change-Id: I18e37287f05398fdaeecc0f0d23984e244f025da
Reviewed-on: https://go-review.googlesource.com/18362
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2016-01-07 21:43:47 +00:00
Keith Randall
b386c34ef9 [dev.ssa] Merge remote-tracking branch 'origin/master' into mergebranch
Semi-regular merge from tip into dev.ssa.

Change-Id: I1627d7c7e6892cd4f1f5da5f3e07389ff1d677ce
2016-01-07 10:01:08 -08:00
Russ Cox
bb91a7e2fd test/bench/shootout: delete
We don't use these for benchmarking anymore.
Now we have the go1 dir and the benchmarks subrepo.
Some have problematic copyright notices, so move out of main repo.

Preserved in golang.org/x/exp/shootout.

Fixes #12688.
Fixes #13584.

Change-Id: Ic0b71191ca1a286d33d7813aca94bab1617a1c82
Reviewed-on: https://go-review.googlesource.com/18320
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-01-06 17:58:27 +00:00
Matthew Dempsky
be20948e27 cmd/compile: recognize bool(true) as a constant expression
Fixes #13821.

Change-Id: I4a28a92d137edac3061537af25ac9d7aba411a66
Reviewed-on: https://go-review.googlesource.com/18262
Reviewed-by: Russ Cox <rsc@golang.org>
2016-01-06 14:38:33 +00:00
Kevin Vu
aaabe3d849 cmd/compile/internal/gc: fix initialization logic
Also add relevant test.

Fixes #13343.

Change-Id: Ib1e65af1d643d501de89adee3618eddbf6c69c9e
Reviewed-on: https://go-review.googlesource.com/18159
Reviewed-by: Russ Cox <rsc@golang.org>
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-01-06 02:10:52 +00:00
David Chase
ab5d2bf92f cmd/compile: suppress export of Note field within exported bodies
Added a format option to inhibit output of .Note field in
printing, and enabled that option during export.
Added test.

Fixes #13777.

Change-Id: I739f9785eb040f2fecbeb96d5a9ceb8c1ca0f772
Reviewed-on: https://go-review.googlesource.com/18217
Reviewed-by: Russ Cox <rsc@golang.org>
Run-TryBot: David Chase <drchase@google.com>
2016-01-05 15:42:12 +00:00
Ian Lance Taylor
bbb88f9091 test: add test that gccgo miscompiled
Change-Id: Ic3f006f86a86de628e14b107f88a5923ea856a58
Reviewed-on: https://go-review.googlesource.com/18093
Reviewed-by: David Symonds <dsymonds@golang.org>
2015-12-22 00:03:45 +00:00
Robert Griesemer
d6a203ecab cmd/compile: const name and label name may match
Fixes #13684.

Change-Id: I3977119b6eb1d6b7dc2ea1e7d6656a8f0d421bc1
Reviewed-on: https://go-review.googlesource.com/18060
Run-TryBot: Robert Griesemer <gri@golang.org>
Reviewed-by: Rob Pike <r@golang.org>
2015-12-21 20:21:28 +00:00
Shenghou Ma
63f0aac586 test: fix linkmain test
Change-Id: Ie8ec4cfc68abef51e52090a75245f96af874c74a
Reviewed-on: https://go-review.googlesource.com/18000
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2015-12-17 23:36:13 +00:00
Russ Cox
c7b1ef9918 cmd/link: reject non-package main toplevel.a file, remove dead code
The test for non-package main top-level inputs is done while parsing
the export data. Issue #13468 happened because we were not parsing
the export data when using compiler-generated archives
(that is, when using go tool compile -pack).

Fix this by parsing the export data even for archives.

However, that turns up a different problem: the export data check
reports (one assumes spurious) skew errors now, because it has
not been run since Go 1.2.
(Go 1.3 was the first release to use go tool compile -pack.)

Since the code hasn't run since Go 1.2, it can't be that important.
Since it doesn't work today, just delete it.

Figuring out how to make this code work with Robert's export
format was one of the largest remaining TODOs for that format.
Now we don't have to.

Fixes #13468 and makes the world a better place.

Change-Id: I40a4b284cf140d49d48b714bd80762d6889acdb9
Reviewed-on: https://go-review.googlesource.com/17976
Reviewed-by: Robert Griesemer <gri@golang.org>
2015-12-17 20:59:51 +00:00
Russ Cox
03c8164849 cmd/compile: fix magic multiply smashing AX
Fixes #12411.

Change-Id: I2202a754c7750e3b2119e3744362c98ca0d2433e
Reviewed-on: https://go-review.googlesource.com/17818
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2015-12-16 20:58:17 +00:00
Russ Cox
63a6f305ef cmd/compile: diagnose invalid switch interface{} case earlier
Fixes #11737.

Change-Id: Id231b502ac5a44035dc3a02515b43bf665cb1e87
Reviewed-on: https://go-review.googlesource.com/17816
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2015-12-16 20:58:00 +00:00
Russ Cox
91c8e5f80b cmd/compile: fix export type conversion loss in inlined func body
Fixes #12677.

Change-Id: I72012f55615fcf5f4a16c054706c9bcd82e49ccd
Reviewed-on: https://go-review.googlesource.com/17817
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2015-12-16 20:30:04 +00:00
Matthew Dempsky
85dd62d5dd cmd/compile: add missing write barriers for return statements
Copying return values to heap-escaped result parameters requires write
barriers.

Fixes #13587.

Change-Id: Ifa04ff7fa4adcc6393acdd82e527beb8f2a00a8b
Reviewed-on: https://go-review.googlesource.com/17762
Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2015-12-12 06:46:56 +00:00
Robert Griesemer
732e2cd746 cmd/compile: don't truncate tiny float constants to 0 in error messages
Fixes #13559.

Change-Id: I6fe8b5083192e8eb6c1b3ca1919fde81a00ccb7e
Reviewed-on: https://go-review.googlesource.com/17695
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Alan Donovan <adonovan@google.com>
2015-12-10 16:39:46 +00:00
Robert Griesemer
c488548967 cmd/compile: recognize labels even if they have the same name as packages
Another (historic) artifact due to partially resolving symbols too early.

Fixes #13539.

Change-Id: Ie720c491cfa399599454f384b3a9735e75d4e8f1
Reviewed-on: https://go-review.googlesource.com/17600
Run-TryBot: Robert Griesemer <gri@golang.org>
Reviewed-by: Damien Neil <dneil@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2015-12-09 02:02:11 +00:00
Didier Spezia
70da2d0a2a cmd/compile/internal/gc: fix internal compiler error on invalid declaration
Following an empty import, a declaration involving a ? symbol
generates an internal compiler error when the name of the
symbol (in newname function).

package a
import""
var?

go.go:2: import path is empty
go.go:3: internal compiler error: newname nil

Make sure dclname is not called when the symbol is nil.
The error message is now:

go.go:2: import path is empty
go.go:3: invalid declaration
go.go:4: syntax error: unexpected EOF

This CL was initially meant to be applied to the old parser,
and has been updated to apply to the new parser.

Fixes #11610

Change-Id: I75e07622fb3af1d104e3a38c89d9e128e3b94522
Reviewed-on: https://go-review.googlesource.com/15268
Reviewed-by: Russ Cox <rsc@golang.org>
2015-12-07 20:21:21 +00:00
Robert Griesemer
715f63778d cmd/compile: avoid converting huge floats to integers
Fixes #13471.

Change-Id: I232ad1729343d020254e313cfff182695ad6fc54
Reviewed-on: https://go-review.googlesource.com/17401
Reviewed-by: Russ Cox <rsc@golang.org>
2015-12-07 20:20:56 +00:00
Didier Spezia
7ebb96a489 cmd/compile/internal/gc: fix panic in Type Stringer
The following code:

func n() {(interface{int})}

generates:

3: interface contains embedded non-interface int
3: type %!v(PANIC=runtime error: invalid memory address or nil pointer dereference) is not an expression

It is because the corresponding symbol (Sym field in Type object)
is nil, resulting in a panic in typefmt.

Just skip the symbol if it is nil, so that the error message becomes:

3: interface contains embedded non-interface int
3: type interface { int } is not an expression

Fixes #11614

Change-Id: I219ae7eb01edca264fad1d4a1bd261d026294b00
Reviewed-on: https://go-review.googlesource.com/14015
Reviewed-by: Russ Cox <rsc@golang.org>
Run-TryBot: Russ Cox <rsc@golang.org>
2015-12-07 20:18:03 +00:00
Russ Cox
05390a0793 misc/cgo/stdio: reenable tests
The build tags are necessary to keep "go build" in that directory
building only stdio.go, but we have to arrange for test/run.go to
treat them as satisfied.

Fixes #12625.

Change-Id: Iec0cb2fdc2c9b24a4e0530be25e940aa0cc9552e
Reviewed-on: https://go-review.googlesource.com/17454
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2015-12-05 21:24:30 +00:00
Matthew Dempsky
336c998291 cmd/compile: reject slice/map/func comparisons against converted nil
Fixes #13480.

Change-Id: Icbf4f83e965e84f7020f56c3f346193f8b91e7bf
Reviewed-on: https://go-review.googlesource.com/17461
Reviewed-by: Russ Cox <rsc@golang.org>
2015-12-05 05:46:48 +00:00
Håvard Haugen
8a34cf7ee0 cmd/compile: don't allow blank method declarations on builtins
Move test for isblank into addmethod so that most of the type checking
for methods is also performed for blank methods.

Fixes #11366.

Change-Id: I13d554723bf96d906d0b3ff390d7b7c87c1a5020
Reviewed-on: https://go-review.googlesource.com/16866
Reviewed-by: Robert Griesemer <gri@golang.org>
2015-12-02 18:26:38 +00:00
Robert Griesemer
e18cd34c76 cmd/compile: use correct line number for := (LCOLAS)
- use same local variable name (lno) for line number for LCOLAS everywhere
- remove now unneeded assignment of line number to yylval.i in lexer

Fix per suggestion of mdempsky.

Fixes #13415.

Change-Id: Ie3c7f5681615042a12b81b26724b3a5d8a979c25
Reviewed-on: https://go-review.googlesource.com/17248
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2015-11-28 03:36:00 +00:00
Robert Griesemer
c7a3403140 cmd/compile: clearer error for invalid array/slice literal elements
Fixes #13365.

Change-Id: I5a447ff806dbbb11c8c75e2b5cfa7fd4a845fb92
Reviewed-on: https://go-review.googlesource.com/17206
Run-TryBot: Robert Griesemer <gri@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2015-11-25 19:49:38 +00:00
Michael Hudson-Doyle
0ae57c3b0b test: add ability to run tests with dynamic linking
This is a bit ugly but it's a useful test. Run go install -buildmode=shared std
and then go run run.go -linkshared (it passes on linux/amd64).

Change-Id: I5684c79cd03817fa1fc399788b7320f8535c08da
Reviewed-on: https://go-review.googlesource.com/16343
Reviewed-by: Russ Cox <rsc@golang.org>
2015-11-24 17:15:43 +00:00
Robert Griesemer
c28a8e4553 test: add test case for issue 13268
See https://go-review.googlesource.com/#/c/17047/ for the bug fix.

Change-Id: Id5b0a37439d0f8f1e668f7c2ac84335b37f3a300
Reviewed-on: https://go-review.googlesource.com/17177
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2015-11-24 04:14:39 +00:00
Caleb Spare
9216d3e344 test: remove dead branch from run.go
It relates to an obsolete notion of 'skipped-but-okay' tests.

Fixes #12394

Change-Id: Ib7e6444dc8565e1390bd42d65d30fac136593f78
Reviewed-on: https://go-review.googlesource.com/17000
Run-TryBot: Caleb Spare <cespare@gmail.com>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Dmitri Shuralyov <shurcool@gmail.com>
2015-11-24 03:20:56 +00:00
Robert Griesemer
aad18b849b cmd/compile: address several more 1.6 TODOs in parser
- fix/check location of popdcl calls where questioned
- remove unnecessary handling of ... (LDDD) in ntype (couldn't be reached)
- inlined and fnret_type and simplified fnres as a consequence
- leave handling of ... (LDDD) in arg_list alone (remove TODO)
- verify that parser requires a ';' after last statement in a case/default
  (added test case)

Fixes #13243.

Change-Id: Iad94b498591a5e85f4cb15bbc01e8e101415560d
Reviewed-on: https://go-review.googlesource.com/17155
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Chris Manghane <cmang@golang.org>
2015-11-21 07:21:23 +00:00
Robert Griesemer
64cd86798b cmd/compile: better syntax error recovery
Use a combination of follow- and stop-token lists and nesting levels
to better synchronize parser after a syntax error.

Fixes #13319.

Change-Id: I9592e0b5b3ba782fb9f9315fea16163328e204f7
Reviewed-on: https://go-review.googlesource.com/17080
Reviewed-by: Chris Manghane <cmang@golang.org>
2015-11-20 19:56:27 +00:00
Robert Griesemer
7218b79f23 cmd/compile: match markdcl and popdcl even in case of errors
Change-Id: I22a8a233bc157fa09cd0283fcd4bc14d90faed70
Reviewed-on: https://go-review.googlesource.com/17066
Reviewed-by: Chris Manghane <cmang@golang.org>
2015-11-20 19:56:11 +00:00
Ian Lance Taylor
f4ccddddae test: add another test that gccgo failed to compile
Change-Id: Ife9e019063473bb0a976cfef4b6e78d951fcb09e
Reviewed-on: https://go-review.googlesource.com/17081
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Minux Ma <minux@golang.org>
2015-11-20 13:31:30 +00:00
Robert Griesemer
fe762b6466 cmd/compile/internal/gc: better error message for parenthesized go/defer exprs
Change-Id: Ie24d56422ae2196198a6c306716fa867c1442d6e
Reviewed-on: https://go-review.googlesource.com/17043
Reviewed-by: Chris Manghane <cmang@golang.org>
2015-11-18 22:26:07 +00:00
Robert Griesemer
5500d46914 cmd/compile/internal/gc: fix incorrect parsing of &(T{}) when followed by {
Handling of &(T{}) assumed that the parser would not introduce ()'s.

Also: Better comments around handling of OPAREN syntax tree optimization.

Fixes #13261.

Change-Id: Ifc5047a0448f5e7d74cd42f6608b87dcc9c2f2fb
Reviewed-on: https://go-review.googlesource.com/17040
Reviewed-by: Chris Manghane <cmang@golang.org>
2015-11-18 22:25:48 +00:00
Robert Griesemer
1a111ea2c7 cmd/compile/internal/gc: fix parsing of <-x (recv op vs recv-only chan)
Also:
- better error messages in some cases
- factored out function to produce syntax error at given line number

Fixes #13273.

Change-Id: I0192a94731cc23444680a26bd0656ef663e6da0b
Reviewed-on: https://go-review.googlesource.com/16992
Reviewed-by: Chris Manghane <cmang@golang.org>
2015-11-18 22:22:56 +00:00
Russ Cox
918a2644f2 cmd/compile: fix Val vs Opt collision
Fixes #12686.

Change-Id: I7a9f49dbd1f60b1d0240de57787753b425f9548c
Reviewed-on: https://go-review.googlesource.com/17031
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2015-11-18 18:31:27 +00:00
Keith Randall
4304fbc4d0 [dev.ssa] Merge remote-tracking branch 'origin/master' into mergebranch
Conflicts:
	src/cmd/compile/internal/gc/racewalk.go
	src/cmd/internal/obj/stack.go
	src/cmd/internal/obj/x86/obj6.go
	src/runtime/stack.go
	test/nilptr3.go
	test/nosplit.go

Change-Id: Ie6053eb1577fd73e8243651f25c0f1fc765ae660
2015-11-16 17:19:42 -08:00
Robert Griesemer
48a14663f8 test: add test case for issue #13248
Issue #13248 was fixed by https://go-review.googlesource.com/#/c/16930/.
This is the corresponding test case (original offending program).

Change-Id: I7c99783db74a5422704409cea7e5073094beadd3
Reviewed-on: https://go-review.googlesource.com/16973
Reviewed-by: Chris Manghane <cmang@golang.org>
2015-11-17 01:05:51 +00:00
Robert Griesemer
0133d24c94 cmd/compile/internal/gc: don't ignore EOF in new parser
Fixes #13274.
Fixes #13272.

Change-Id: Ie67a2c4671ee2b49831898fff7677cd65d780942
Reviewed-on: https://go-review.googlesource.com/16972
Reviewed-by: Chris Manghane <cmang@golang.org>
2015-11-17 01:05:39 +00:00
Robert Griesemer
a20556bf56 cmd/compile/internal/gc: correctly use internal call to error reporting
Fixes #13266.

Change-Id: I31da922e0599989e52acf346374c2077b157ebb7
Reviewed-on: https://go-review.googlesource.com/16971
Reviewed-by: Chris Manghane <cmang@golang.org>
2015-11-17 01:05:07 +00:00
Robert Griesemer
fbe855ba29 test: fix test case
Issue introduced by https://go-review.googlesource.com/#/c/16920/ .

TBR=rsc

Change-Id: I2a0e0c81f641f869568230837c566913f6538f37
Reviewed-on: https://go-review.googlesource.com/16990
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
2015-11-16 23:49:54 +00:00
Russ Cox
2c11164db5 cmd/compile: fix value range check for complex constants
Fixes #11590.

Change-Id: I4144107334604a2cc98c7984df3b5d4cde3d30af
Reviewed-on: https://go-review.googlesource.com/16920
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2015-11-16 20:48:47 +00:00
Russ Cox
292ad59291 cmd/compile: do not emit args_stackmap for func _
Fixes #11699.

Change-Id: I01bf506d76260bcdf828bbde52791e328aa441a5
Reviewed-on: https://go-review.googlesource.com/16921
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2015-11-16 20:38:52 +00:00
Russ Cox
247959d9b8 cmd/compile: reject identifiers beginning with non-ASCII digit
Fixes #11359.

Change-Id: I0fdfa410939f7e42020cbb19d74a67e1cc3cd610
Reviewed-on: https://go-review.googlesource.com/16919
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2015-11-16 20:38:42 +00:00
Robert Griesemer
b569b87ca1 cmd/compile/internal/gc: recursive-descent parser
This is a translation of the yacc-based parser with adjustements
to make the grammar work for a recursive-descent parser followed
by cleanups and simplifications.

The yacc actions were mostly literally copied for correctness
with better temporary names.

A few of the syntax tests were adjusted for slightly different
error messages (it is very difficult to match the yacc-based
error messages in all cases, and sometimes the new parser could
produce better errors).

The new parser is enabled by default.
To switch back to the yacc-based parser, set -oldparser.
To hardwire the switch back, uncomment "oldparser = 1" in lex.go.

- passes all.bash
- ~18% reduced parse time per file on average for make.bash
- ~3% reduced compile time for building cmd/compile

Change-Id: Icb5651bb9d8b9f66261762d2c94a03793050d4ce
Reviewed-on: https://go-review.googlesource.com/16665
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2015-11-13 14:53:57 +00:00
Michael Hudson-Doyle
c1b6e392f5 cmd/internal/obj, cmd/link, runtime: increase stack limit to accommodate larger frames on ppc64x
Larger stack frames mean nosplit functions use more stack and so the limit
needs to increase.

The change to test/nosplit.go is a bit ugly but I can't really think of a
way to make it nicer.

Change-Id: I2616b58015f0b62abbd62951575fcd0d2d8643c2
Reviewed-on: https://go-review.googlesource.com/16504
Reviewed-by: Russ Cox <rsc@golang.org>
2015-11-12 22:32:16 +00:00
Austin Clements
a9ca2137aa test: really force heap profile update in heapsampling.go
The heap profile is only guaranteed to be up-to-date after two GC
cycles, so force two GCs instead of just one.

Updates #13098.

Change-Id: I4fb9287b698f4a3b90b8af9fc6a2efb3b082bfe5
Reviewed-on: https://go-review.googlesource.com/16848
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
2015-11-12 18:32:13 +00:00
Austin Clements
b5a0c67fcc test: force heap profile update in heapsampling.go test
The heapsampling.go test occasionally fails on some architectures
because it finds zero heap samples in main.alloc. This happens because
the byte and object counts are only updated at a GC. Hence, if a GC
happens part way through allocInterleaved, but then doesn't happen
after we start calling main.alloc, checkAllocations will see buckets
for the lines in main.alloc (which are created eagerly), but the
object and byte counts will be zero.

Fix this by forcing a GC to update the profile before we collect it.

Fixes #13098.

Change-Id: Ia7a9918eea6399307f10499dd7abefd4f6d13cf6
Reviewed-on: https://go-review.googlesource.com/16846
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
2015-11-12 16:58:52 +00:00
Yao Zhang
15676b51a5 test: fix nosplit.go, fixedbugs/issue11656.go and skip two tests for mips64{,le}
Skip fixedbugs/issue10607.go because external linking is not supported
yet.

Skip nilptr3.go because of issue #9058 (same as ppc64).

Change-Id: Ib3dfbd9a03ee4052871cf57c74b3cc5e745e1f80
Reviewed-on: https://go-review.googlesource.com/14461
Reviewed-by: Minux Ma <minux@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Minux Ma <minux@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2015-11-12 04:52:31 +00:00
Keith Randall
e410a527b2 runtime: simplify chan ops, take 2
This change is the same as CL #9345 which was reverted,
except for a small bug fix.

The only change is to the body of sendDirect and its callsite.
Also added a test.

The problem was during a channel send operation.  The target
of the send was a sleeping goroutine waiting to receive.  We
basically do:
1) Read the destination pointer out of the sudog structure
2) Copy the value we're sending to that destination pointer
Unfortunately, the previous change had a goroutine suspend
point between 1 & 2 (the call to sendDirect).  At that point
the destination goroutine's stack could be copied (shrunk).
The pointer we read in step 1 is no longer valid for step 2.

Fixed by not allowing any suspension points between 1 & 2.
I suspect the old code worked correctly basically by accident.

Fixes #13169

The original 9345:

This change removes the retry mechanism we use for buffered channels.
Instead, any sender waking up a receiver or vice versa completes the
full protocol with its counterpart.  This means the counterpart does
not need to relock the channel when it wakes up.  (Currently
buffered channels need to relock on wakeup.)

For sends on a channel with waiting receivers, this change replaces
two copies (sender->queue, queue->receiver) with one (sender->receiver).
For receives on channels with a waiting sender, two copies are still required.

This change unifies to a large degree the algorithm for buffered
and unbuffered channels, simplifying the overall implementation.

Fixes #11506

Change-Id: I57dfa3fc219cffa4d48301ee15fe5479299efa09
Reviewed-on: https://go-review.googlesource.com/16740
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2015-11-08 23:20:25 +00:00
Keith Randall
4b7d5f0b94 runtime: memmove/memclr pointers atomically
Make sure that we're moving or zeroing pointers atomically.
Anything that is a multiple of pointer size and at least
pointer aligned might have pointers in it.  All the code looks
ok except for the 1-pointer-sized moves.

Fixes #13160
Update #12552

Change-Id: Ib97d9b918fa9f4cc5c56c67ed90255b7fdfb7b45
Reviewed-on: https://go-review.googlesource.com/16668
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2015-11-07 02:42:12 +00:00
Keith Randall
ffb20631fc runtime: teach peephole optimizer that duffcopy clobbers X0
Duffcopy now uses X0, as of 5cf281a.  Teach the peephole
optimizer that duffcopy clobbers X0 so that it does not
rename registers use X0 across the duffcopy instruction.

Fixes #13171

Change-Id: I389cbf1982cb6eb2f51e6152ac96736a8589f085
Reviewed-on: https://go-review.googlesource.com/16715
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: Minux Ma <minux@golang.org>
Reviewed-by: Ilya Tocar <ilya.tocar@intel.com>
2015-11-06 15:11:42 +00:00
Michael Hudson-Doyle
10c0753761 cmd/internal/obj/ppc64: fix assembly of SRADCC with immediate
sradi and sradi. hide the top bit of their immediate argument apart from the
rest of it, but the code only handled the sradi case.

I'm pretty sure this is the only instruction missing (a couple of the rotate
instructions encode their immediate the same way but their handling looks OK).

This fixes the failure of "GOARCH=amd64 ~/go/bin/go install -v runtime" as
reported in the bug.

Fixes #11987

Change-Id: I0cdefcd7a04e0e8fce45827e7054ffde9a83f589
Reviewed-on: https://go-review.googlesource.com/16710
Reviewed-by: Minux Ma <minux@golang.org>
2015-11-05 22:54:21 +00:00
Dmitry Vyukov
bf606094ee runtime: fix finalization and profiling of tiny allocations
Handling of special records for tiny allocations has two problems:
1. Once we queue a finalizer we mark the object. As the result any
   subsequent finalizers for the same object will not be queued
   during this GC cycle. If we have 16 finalizers setup (the worst case),
   finalization will take 16 GC cycles. This is what caused misbehave
   of tinyfin.go. The actual flakiness was caused by the fact that fing
   is asynchronous and don't always run before the check.
2. If a tiny block has both finalizer and profile specials,
   it is possible that we both queue finalizer, preserve the object live
   and free the profile record. As the result heap profile can be skewed.

Fix both issues by analyzing all special records for a single object at once.

Also, make tinyfin test stricter and remove reliance on real time.

Also, add a test for the problem 2. Currently heap profile missed about
a half of live memory.

Fixes #13100

Change-Id: I9ae4dc1c44893724138a4565ca5cae29f2e97544
Reviewed-on: https://go-review.googlesource.com/16591
Reviewed-by: Austin Clements <austin@google.com>
Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: Dmitry Vyukov <dvyukov@google.com>
2015-11-03 18:57:18 +00:00
Todd Neal
e3e0122ae2 test: use go:noinline consistently
Replace various implementations of inlining prevention with
"go:noinline"

Change-Id: Iac90895c3a62d6f4b7a6c72e11e165d15a0abfa4
Reviewed-on: https://go-review.googlesource.com/16510
Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: Todd Neal <todd@tneal.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2015-11-03 02:01:34 +00:00
Brad Fitzpatrick
d2fa937a21 test: update tinyfin test
* use new(int32) to be pedantic about documented SetFinalizer rules:
  "The argument x must be a pointer to an object allocated by calling
  new or by taking the address of a composite literal"

* remove the amd64-only restriction. The GC is fully precise everywhere
  now, even on 32-bit. (keep the gccgo restriction, though)

* remove a data race (perhaps the actual bug) and use atomic.LoadInt32
  for the final check. The race detector is now happy, too.

Updates #13100

Change-Id: I8d05c0ac4f046af9ba05701ad709c57984b34893
Reviewed-on: https://go-review.googlesource.com/16535
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2015-11-02 16:08:33 +00:00
Ian Lance Taylor
a4fb8c13db test: add gcc6798, valid code that caused gccgo to crash
Change-Id: I288bd3091ea81db7b616747cbec8958a31d98b7e
Reviewed-on: https://go-review.googlesource.com/16532
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2015-11-01 21:17:01 +00:00
Brad Fitzpatrick
7c167f2708 test: disable flaky heapsampling test for now
Flaky tests do more harm than good.

Updates #13098

Change-Id: I179ed810b49bbb96c8df462bfa20b70231b26772
Reviewed-on: https://go-review.googlesource.com/16521
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2015-10-30 20:48:03 +00:00
David Chase
729abfa35c [dev.ssa] cmd/compile: default compile+test with SSA
Some tests disabled, some bifurcated into _ssa and not,
with appropriate logging added to compiler.

"tests/live.go" in particular needs attention.

SSA-specific testing removed, since it's all SSA now.

Added "-run_skips" option to tests/run.go to simplify
checking whether a test still fails (or how it fails)
on a skipped platform.

The compiler now compiles with SSA by default.
If you don't want SSA, specify GOSSAHASH=n (or N) as
an environment variable.  Function names ending in "_ssa"
are always SSA-compiled.

GOSSAFUNC=fname retains its "SSA for fname, log to ssa.html"
GOSSAPKG=pkg only has an effect when GOSSAHASH=n
GOSSAHASH=10101 etc retains its name-hash-matching behavior
for purposes of debugging.

See #13068

Change-Id: I8217bfeb34173533eaeb391b5f6935483c7d6b43
Reviewed-on: https://go-review.googlesource.com/16299
Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: David Chase <drchase@google.com>
2015-10-30 20:35:20 +00:00
Todd Neal
a92543e1a1 cmd/compile: add support for a go:noinline directive
Some tests need to disable inlining of a function.  It's currently done
in one of a few ways (adding a function call, an empty switch, or a
defer).  Add support for a less fragile 'go:noinline' directive that
prevents inlining.

Fixes #12312

Change-Id: Ife444e13361b4a927709d81aa41e448f32eec8d4
Reviewed-on: https://go-review.googlesource.com/13911
Run-TryBot: Todd Neal <todd@tneal.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
2015-10-29 23:16:27 +00:00
David Chase
e99dd52066 [dev.ssa] cmd/compile: enhance SSA filtering, add OpConvert
Modified GOSSA{HASH.PKG} environment variable filters to
make it easier to make/run with all SSA for testing.
Disable attempts at SSA for architectures that are not
amd64 (avoid spurious errors/unimplementeds.)

Removed easy out for unimplemented features.

Add convert op for proper liveness in presence of uintptr
to/from unsafe.Pointer conversions.

Tweaked stack sizes to get a pass on windows;
1024 instead 768, was observed to pass at least once.

Change-Id: Ida3800afcda67d529e3b1cf48ca4a3f0fa48b2c5
Reviewed-on: https://go-review.googlesource.com/16201
Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: David Chase <drchase@google.com>
2015-10-23 19:32:57 +00:00
acanino
b60c8203ea cmd/compile: "invalid variable name x in type switch", where x is a name of a constant
Small fix: looks like a short variable declaration with a type switch
checks to make sure the variable used had valid shape (ONAME, OTYPE, or
ONONAME) and rejects everything else. Then a new variable is declared.
If the symbol contained in the declaration was a named OLITERAL (still a
valid identifier obviously) it would be rejected, even though a new
variable would have been declared.

Fix adds this case to the check.

Added a test case from issue12413.

Fixes #12413

Change-Id: I150dadafa8ee5612c867d58031027f2dca8c6ebc
Reviewed-on: https://go-review.googlesource.com/15760
Reviewed-by: Minux Ma <minux@golang.org>
Run-TryBot: Minux Ma <minux@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2015-10-21 04:21:16 +00:00
Robert Griesemer
76285213b8 cmd/compile/internal/gc: there are no -0 floating-point constants
Fixes #12577.

Change-Id: Id469cd92f5f9436b0ef948ee1a252ed1842bc7aa
Reviewed-on: https://go-review.googlesource.com/16133
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2015-10-20 22:11:11 +00:00