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2198 Commits

Author SHA1 Message Date
Michael Hudson-Doyle
b92a0a8969 cmd/internal/gc, cmd/go: fix value of importpath symbol
In https://golang.org/cl/7797 I attempted to use myimportpath to set the value
of the go.importpath.$foo. symbol for the module being compiled, but I messed
it up and only set the name (which the linker rewrites anyway). This lead to
the importpath for the module being compiled being "". This was hard to notice,
because all modules that import another define the importpath for their
imported modules correctly -- but main is not imported, and this meant that the
reflect module saw all fields of all types defined in the main module as
exported.

The fix is to do what I meant to do the first time, add a test and change the
go tool to compile main packages with -p main and not -p
command-line-arguments.

Fixes #10332

Change-Id: I5fc6e9b1dc2b26f058641e382f9a56a526eca291
Reviewed-on: https://go-review.googlesource.com/8481
Reviewed-by: Russ Cox <rsc@golang.org>
2015-04-19 20:14:59 +00:00
Dmitry Vyukov
24f246c1b6 cmd/gc: fix crash during escape analysis
Fixes #10441

Compiler crashed as:

panic: runtime error: invalid memory address or nil pointer dereference
goroutine 1 [running]:
cmd/internal/gc.haspointers(0x0, 0xffffffffffffffff)
    src/cmd/internal/gc/reflect.go:623 +0x1f
cmd/internal/gc.escwalk(0x20c82dc00, 0xffffffffffffffff, 0x20c82dda0, 0x20c835520)
    src/cmd/internal/gc/esc.go:1291 +0x14aa
cmd/internal/gc.escwalk(0x20c82dc00, 0xffffffffffffffff, 0x20c82dda0, 0x20beac340)
    src/cmd/internal/gc/esc.go:1386 +0x836

while evaluating haspointers of the fake OADDR node here:

	leaks = level <= 0 && dst.Escloopdepth < src.Escloopdepth || level < 0 && dst == &e.funcParam && haspointers(src.Type)

Change-Id: I13c23fced52e8fcd0ae1df81b374df8632eb7790
Reviewed-on: https://go-review.googlesource.com/8932
Reviewed-by: David Chase <drchase@google.com>
Run-TryBot: Dmitry Vyukov <dvyukov@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2015-04-14 15:45:26 +00:00
Ian Lance Taylor
607d5158c1 test: add gcc65755.go for http://gcc.gnu.org/PR65755
Change-Id: Ic35dff4c9a7fc6716ef9d5553a7b1769bed9be01
Reviewed-on: https://go-review.googlesource.com/8892
Reviewed-by: Minux Ma <minux@golang.org>
2015-04-13 23:24:30 +00:00
Shenghou Ma
399b3e3230 test: add gccgo test case for #10407
Change-Id: I8d17e2b0fbc529ca7958c75222964a5e419aa3db
Reviewed-on: https://go-review.googlesource.com/8717
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2015-04-10 22:51:46 +00:00
Dmitry Vyukov
7647741246 test: add -update_errors flag to run script
The flag updates error annotations in test files from actual compiler output.
This is useful when doing compiler changes that add/remove/change lots of errors,
or when adding lots of new tests.
Also I noticed at least 2 cases where annotation were sub-optimal:
1. The annotation was "leaking param p" when the actual error is
"leaking param p to result ~r1".
2. The annotation was "leaking param m" when the actual errors
are "leaking param m" and "leaking param mv1".

For now it works only for errorcheck mode.

Also, apply the update to escape and liveness tests.
Some files have gccgo-specific errors of the form "gc error|gccgo error",
so it is risky to run update on all files. Gccgo-specific error
does not necessary contain '|', it can be just truncated.

Change-Id: Iaaae767f859dcb8321a8cb4970b2b70969e8a345
Reviewed-on: https://go-review.googlesource.com/5310
Run-TryBot: Dmitry Vyukov <dvyukov@google.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2015-04-10 11:33:42 +00:00
Dmitry Vyukov
878a86a129 cmd/gc: fix escape analysis of closures
Fixes #10353

See test/escape2.go:issue10353. Previously new(int) did not escape to heap,
and so heap-allcated closure was referencing a stack var. This breaks
the invariant that heap must not contain pointers to stack.

Look at the following program:

package main

func main() {
	foo(new(int))
	bar(new(int))
}

func foo(x *int) func() {
	return func() {
		println(*x)
	}
}

// Models what foo effectively does.
func bar(x *int) *C {
	return &C{x}
}

type C struct {
	x *int
}

Without this patch escape analysis works as follows:

$ go build -gcflags="-m -m -m -l" esc.go
escflood:1: dst ~r1 scope:foo[0]
escwalk: level:0 depth:0  func literal( l(9) f(1) esc(no) ld(1)) scope:foo[1]
/tmp/live2.go:9: func literal escapes to heap
escwalk: level:0 depth:1 	 x( l(8) class(PPARAM) f(1) esc(no) ld(1)) scope:foo[1]
/tmp/live2.go:8: leaking param: x to result ~r1

escflood:2: dst ~r1 scope:bar[0]
escwalk: level:0 depth:0  &C literal( l(15) esc(no) ld(1)) scope:bar[1]
/tmp/live2.go:15: &C literal escapes to heap
escwalk: level:-1 depth:1 	 &C literal( l(15)) scope:bar[0]
escwalk: level:-1 depth:2 		 x( l(14) class(PPARAM) f(1) esc(no) ld(1)) scope:bar[1]
/tmp/live2.go:14: leaking param: x

/tmp/live2.go:5: new(int) escapes to heap
/tmp/live2.go:4: main new(int) does not escape

new(int) does not escape while being captured by the closure.
With this patch escape analysis of foo and bar works similarly:

$ go build -gcflags="-m -m -m -l" esc.go
escflood:1: dst ~r1 scope:foo[0]
escwalk: level:0 depth:0  &(func literal)( l(9)) scope:foo[0]
escwalk: level:-1 depth:1 	 func literal( l(9) f(1) esc(no) ld(1)) scope:foo[1]
/tmp/live2.go:9: func literal escapes to heap
escwalk: level:-1 depth:2 		 x( l(8) class(PPARAM) f(1) esc(no) ld(1)) scope:foo[1]
/tmp/live2.go:8: leaking param: x

escflood:2: dst ~r1 scope:bar[0]
escwalk: level:0 depth:0  &C literal( l(15) esc(no) ld(1)) scope:bar[1]
/tmp/live2.go:15: &C literal escapes to heap
escwalk: level:-1 depth:1 	 &C literal( l(15)) scope:bar[0]
escwalk: level:-1 depth:2 		 x( l(14) class(PPARAM) f(1) esc(no) ld(1)) scope:bar[1]
/tmp/live2.go:14: leaking param: x

/tmp/live2.go:4: new(int) escapes to heap
/tmp/live2.go:5: new(int) escapes to heap

Change-Id: Ifd14b7ae3fc11820e3b5eb31eb07f35a22ed0932
Reviewed-on: https://go-review.googlesource.com/8408
Reviewed-by: Russ Cox <rsc@golang.org>
Run-TryBot: Dmitry Vyukov <dvyukov@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2015-04-09 09:56:27 +00:00
Shenghou Ma
63d72f6901 cmd/7g: enable peephole optimizer
Based on cmd/9g/peep.go.

Go 1 benchmark comparison:
benchmark                          old ns/op       new ns/op       delta
BenchmarkBinaryTree17              24328574000     18351639000     -24.57%
BenchmarkFannkuch11                17029365000     10817758000     -36.48%
BenchmarkFmtFprintfEmpty           291             223             -23.37%
BenchmarkFmtFprintfString          1073            799             -25.54%
BenchmarkFmtFprintfInt             1024            778             -24.02%
BenchmarkFmtFprintfIntInt          1654            1277            -22.79%
BenchmarkFmtFprintfPrefixedInt     1360            1083            -20.37%
BenchmarkFmtFprintfFloat           2272            1415            -37.72%
BenchmarkFmtManyArgs               5933            4742            -20.07%
BenchmarkGobDecode                 53166003        38584736        -27.43%
BenchmarkGobEncode                 37930156        30074874        -20.71%
BenchmarkGzip                      1880638900      1286832100      -31.57%
BenchmarkGunzip                    386343633       292194480       -24.37%
BenchmarkHTTPClientServer          237077          179776          -24.17%
BenchmarkJSONEncode                101731690       73116925        -28.13%
BenchmarkJSONDecode                344655360       241277600       -29.99%
BenchmarkMandelbrot200             28329778        12950809        -54.29%
BenchmarkGoParse                   21670755        16554244        -23.61%
BenchmarkRegexpMatchEasy0_32       557             484             -13.11%
BenchmarkRegexpMatchEasy0_1K       4687            4832            +3.09%
BenchmarkRegexpMatchEasy1_32       539             483             -10.39%
BenchmarkRegexpMatchEasy1_1K       5100            5080            -0.39%
BenchmarkRegexpMatchMedium_32      796             651             -18.22%
BenchmarkRegexpMatchMedium_1K      233099          182047          -21.90%
BenchmarkRegexpMatchHard_32        13202           9897            -25.03%
BenchmarkRegexpMatchHard_1K        401027          303602          -24.29%
BenchmarkRevcomp                   3837679666      2816546600      -26.61%
BenchmarkTemplate                  440608300       324831040       -26.28%
BenchmarkTimeParse                 1460            1019            -30.21%
BenchmarkTimeFormat                1609            1174            -27.04%

benchmark                         old MB/s     new MB/s     speedup
BenchmarkGobDecode                14.44        19.89        1.38x
BenchmarkGobEncode                20.24        25.52        1.26x
BenchmarkGzip                     10.32        15.08        1.46x
BenchmarkGunzip                   50.23        66.41        1.32x
BenchmarkJSONEncode               19.07        26.54        1.39x
BenchmarkJSONDecode               5.63         8.04         1.43x
BenchmarkGoParse                  2.67         3.50         1.31x
BenchmarkRegexpMatchEasy0_32      57.38        66.05        1.15x
BenchmarkRegexpMatchEasy0_1K      218.47       211.91       0.97x
BenchmarkRegexpMatchEasy1_32      59.29        66.21        1.12x
BenchmarkRegexpMatchEasy1_1K      200.76       201.54       1.00x
BenchmarkRegexpMatchMedium_32     1.26         1.53         1.21x
BenchmarkRegexpMatchMedium_1K     4.39         5.62         1.28x
BenchmarkRegexpMatchHard_32       2.42         3.23         1.33x
BenchmarkRegexpMatchHard_1K       2.55         3.37         1.32x
BenchmarkRevcomp                  66.23        90.24        1.36x
BenchmarkTemplate                 4.40         5.97         1.36x

Fixes #10105.

Change-Id: I353cc9fdf922e431821508c9dbbe4d9a85d64bd4
Signed-off-by: Shenghou Ma <minux@golang.org>
Reviewed-on: https://go-review.googlesource.com/8471
Reviewed-by: Dave Cheney <dave@cheney.net>
2015-04-08 08:16:54 +00:00
Matthew Dempsky
4f2a73011f cmd/internal/gc, cmd/yacc: restore remaining custom error messages
This CL extends cmd/yacc to expose a yyErrorVerbose variable that
changes the error messages from just "syntax error" to "syntax error:
unexpected ${tokname}".

It also moves the yyToknames table generation to after rules have been
processed so that entries can be generated for tokens that aren't
mentioned in the preamble (e.g., '.' in the case of go.y).

Lastly, it restores gc's old code for applying yytfix to yyToknames,
except that substituting "LLITERAL" with litbuf happens in Yyerror.

Fixes #9968.

Change-Id: Icec188d11fdabc1dae31b8a471c35b5c7f6deec7
Reviewed-on: https://go-review.googlesource.com/8432
Reviewed-by: Russ Cox <rsc@golang.org>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2015-04-03 23:40:40 +00:00
David Crawshaw
ca0adeddd5 cmd/7g: reserve registers R26 to R32
These registers are not available for programs to use. Prior to this
change, the compiler would crash attempting to use ZR as a general
purpose register. Other programs would compile but on execution would
overwrite the G register and cause havoc.

Fixes linux/arm64 build.
Fixes #10304
Fixes #10320

Change-Id: I5cf51d3b77cfe3db7dd6377324950cafb02f8d8b
Reviewed-on: https://go-review.googlesource.com/8456
Reviewed-by: Minux Ma <minux@golang.org>
2015-04-03 18:25:09 +00:00
Robert Griesemer
a51d5f27e8 cmd/internal/gc: use 512 bits (rather than 464) for multi-precision arithmetic
The original implementation used 16 int "words" but only 29 bits per word
for a total of 16*29 = 464 bits, with a space consumption of 16*64 = 1024
bits on a 64 bit machine. Switching to 512 bits increases precision while
still using (in the worst case) half the amount of memory per mp value on
a 64 bit machine.

Also: Decreased permitted number of least-significant mantissa bits which
may be incorrect when considering if a precise floating-point constant is
an integer from 29 to 16 bits.

Change-Id: Iee9287056f0e9aa4f06ceac0724ff4674f710c53
Reviewed-on: https://go-review.googlesource.com/8429
Reviewed-by: Russ Cox <rsc@golang.org>
2015-04-03 17:13:07 +00:00
Robert Griesemer
5bb89eb009 cmd/internal/gc: use big.Float to represent Mpflt bits
All multi-precision arithmetic is now based on math/big.

- passes all.bash
- added test cases for fixed bugs

Fixes #7740.
Fixes #6866.

Change-Id: I67268b91766970ced3b928260053ccdce8753d58
Reviewed-on: https://go-review.googlesource.com/7912
Reviewed-by: Russ Cox <rsc@golang.org>
2015-04-02 22:49:47 +00:00
Matthew Dempsky
398bf9d5a0 cmd/internal/gc, cmd/yacc: restore custom syntax error messages
This restores go.errors from before 3af0d79 along with a fixed up
version of the bisonerrors AWK script, translated to Go.

However, this means Yyerror needs access to the yacc parser's state,
which is currently private.  To workaround that, add a "state"
accessor method like the Lookahead method added in c7fa3c6.

Update issue #9968.

Change-Id: Ib868789e92fdb7d135442120a392457923e50121
Reviewed-on: https://go-review.googlesource.com/7270
Reviewed-by: Russ Cox <rsc@golang.org>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2015-04-02 21:56:24 +00:00
David Crawshaw
33448d963c cmd/7g: fix ACMP entry in progtable
On arm64, CMP $foo, R is encoded as from=$foo, reg=R, not as from=$foo,
to=R. The progtable entry for ACMP incorrectly described the latter
form. Because of this, the registerizer was not accounting the registers
used in CMP instructions and was incorrectly re-assigning those registers.

This was an old problem, but it only became apparent after b115c35
(cmd/internal/gc: move cgen, regalloc, et al to portable code). Previous
to this commit, the compiler used a slightly larger register set for the
temps than it used for register variables. Since it had plenty registers
dedicated to temps, the registers used in CMP instruction never clashed
with registers assigned to register variables.

Fixes #10253

Change-Id: Iedf4bd882bd59440dff310ac0f81e0f53d80d7ed
Reviewed-on: https://go-review.googlesource.com/8387
Reviewed-by: Aram Hăvărneanu <aram@mgk.ro>
Reviewed-by: Rob Pike <r@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
Reviewed-by: Minux Ma <minux@golang.org>
2015-04-02 20:18:28 +00:00
Shenghou Ma
73c026e6fe test: add testcase for gccgo-specific issue 10284
Change-Id: I624b336a9eb27fbbc8ef13f141023b4f60966245
Reviewed-on: https://go-review.googlesource.com/8240
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2015-03-30 19:31:35 +00:00
David Chase
2270133981 cmd/gc: allocate backing storage for non-escaping interfaces on stack
Extend escape analysis to convT2E and conT2I. If the interface value
does not escape supply runtime with a stack buffer for the object copy.

This is a straight port from .c to .go of Dmitry's patch

Change-Id: Ic315dd50d144d94dd3324227099c116be5ca70b6
Reviewed-on: https://go-review.googlesource.com/8201
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
2015-03-30 16:11:22 +00:00
Dmitry Vyukov
d593f4a4d5 test: add tests for escape analysis of function parameters
False positives (var incorrectly escapes) are marked with BAD.

Change-Id: I002ac5965ec6748adafa2c4c657c97d8f7ff75d0
Reviewed-on: https://go-review.googlesource.com/5311
Reviewed-by: Keith Randall <khr@golang.org>
2015-03-30 10:12:05 +00:00
Dmitry Vyukov
edcc062bdc test: add tests for escape analysis of interface conversions
The false positives (var incorrectly escapes) are marked with BAD.

Change-Id: If64fabb6ea96de44a1177d9ab12e2ccc579fe0c4
Reviewed-on: https://go-review.googlesource.com/5294
Reviewed-by: Keith Randall <khr@golang.org>
2015-03-28 16:15:27 +00:00
Dmitry Vyukov
8a2545744b test: add tests for escape analysis of closure arguments
10 false positives (var incorrectly escapes to heap) are marked with BAD.

Change-Id: I773b13a18ff55aaa499a2a28a979118422cc5322
Reviewed-on: https://go-review.googlesource.com/5293
Reviewed-by: Keith Randall <khr@golang.org>
2015-03-28 15:08:09 +00:00
Dmitry Vyukov
8205bfb566 test: fix build
Fix build after http://golang.org/cl/5297
The compiler was changed to not print implicit map capacity in error messages.

Change-Id: I852f668680c3c69c5eecc7964e46202a97014d6a
Reviewed-on: https://go-review.googlesource.com/8212
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
2015-03-28 15:02:39 +00:00
Dmitry Vyukov
6d9fd7e65b test: add tests for indirection level computation in escape analysis
The false positive (var incorrectly escapes to heap) is marked with BAD.

Change-Id: I11877fa8e976094b31a221abd88ae32d351c85ee
Reviewed-on: https://go-review.googlesource.com/5292
Reviewed-by: Keith Randall <khr@golang.org>
2015-03-28 13:43:27 +00:00
Dmitry Vyukov
130538bb9a test: add escape analysis tests form maps
False positives (var incorrectly escapes) are marked with BAD.

Change-Id: I8383fa3f77e2156d781d994968636ba9a17bb975
Reviewed-on: https://go-review.googlesource.com/5297
Reviewed-by: Keith Randall <khr@golang.org>
2015-03-28 13:41:09 +00:00
Dmitry Vyukov
a21537ff74 test: add tests for escape analysis when assigning to indirections
False positives (var incorrectly escapes) are marked with BAD.

Change-Id: I0114d87ee467fe1e3b27642f8c5a04d4a9664211
Reviewed-on: https://go-review.googlesource.com/5295
Reviewed-by: Keith Randall <khr@golang.org>
2015-03-28 13:38:45 +00:00
Dmitry Vyukov
097b1e0b73 test: add escape analysis tests for fields
False positives (var incorrectly escapes) are marked with BAD.

Change-Id: I3027b6e0f5b48325e6169599400cc59e1394809f
Reviewed-on: https://go-review.googlesource.com/5431
Reviewed-by: Keith Randall <khr@golang.org>
2015-03-28 13:31:26 +00:00
Dmitry Vyukov
0558f12123 test: add tests for escape analysis of slices
False positives (var incorrectly escapes) are marked with BAD.

Change-Id: I9e9a3f71b060520103bcf289829a2efdf6f2b517
Reviewed-on: https://go-review.googlesource.com/5298
Reviewed-by: Keith Randall <khr@golang.org>
2015-03-28 13:18:42 +00:00
Dmitry Vyukov
1f5617e37c test: add additional ... tests for escape analysis
False positives (var incorrectly escapes) are marked with BAD.

Change-Id: I646a29ffe24d963c63db09cba81dbc101d7c7242
Reviewed-on: https://go-review.googlesource.com/5296
Reviewed-by: Keith Randall <khr@golang.org>
2015-03-28 13:07:19 +00:00
Russ Cox
4224d81fae cmd/internal/gc: inline x := y.(*T) and x, ok := y.(*T)
These can be implemented with just a compare and a move instruction.
Do so, avoiding the overhead of a call into the runtime.

These assertions are a significant cost in Go code that uses interface{}
as a safe alternative to C's void* (or unsafe.Pointer), such as the
current version of the Go compiler.

*T here includes pointer to T but also any Go type represented as
a single pointer (chan, func, map). It does not include [1]*T or struct{*int}.
That requires more work in other parts of the compiler; there is a TODO.

Change-Id: I7ff681c20d2c3eb6ad11dd7b3a37b1f3dda23965
Reviewed-on: https://go-review.googlesource.com/7862
Reviewed-by: Rob Pike <r@golang.org>
2015-03-20 20:05:37 +00:00
Dave Cheney
1f3fe91066 test: fix recover4 test on 64kb systems
Fix recover4.go to work on 64kb systems.

Change-Id: I211cb048de1268a8bbac77c6f3a1e0b8c8277594
Reviewed-on: https://go-review.googlesource.com/7673
Reviewed-by: Minux Ma <minux@golang.org>
2015-03-17 05:25:01 +00:00
Dave Cheney
3eaea873b4 Revert "test: disable recover4 test to fix ppc64 builds"
This reverts commit 1313e7982f.

Change-Id: I96cc58baf71156fdfbf8fd61332744bcc3ea52e5
Reviewed-on: https://go-review.googlesource.com/7670
Reviewed-by: Dave Cheney <dave@cheney.net>
2015-03-17 03:38:38 +00:00
Dave Cheney
1313e7982f test: disable recover4 test to fix ppc64 builds
Updates #10180

Temporarily disable this test on ppc64 systems as all our builders use 64k page size.

We need a portable way to get the page size of the host so we can correctly size the mmap hole.

Change-Id: Ibd36ebe2f54cf75a44667e2070c385f0daaca481
Reviewed-on: https://go-review.googlesource.com/7652
Reviewed-by: Andrew Gerrand <adg@golang.org>
2015-03-17 02:58:17 +00:00
Russ Cox
0c31992eb3 test: add test that variables captured by deferred funcs are current on fault
This came up in private mail.
It works today and I want to make sure it stays working.

Change-Id: I13ebdc2dfadb3c72d7f179be89883137320c05d0
Reviewed-on: https://go-review.googlesource.com/7390
Reviewed-by: Austin Clements <austin@google.com>
Reviewed-by: Rob Pike <r@golang.org>
2015-03-16 23:07:06 +00:00
Aram Hăvărneanu
ddf6d8005d test: fix nosplit test, and disable nilptr3 test on arm64
Change-Id: I5d40e04395de743a8fdcfa8bdc0e580729bc66a3
Reviewed-on: https://go-review.googlesource.com/7147
Reviewed-by: Minux Ma <minux@golang.org>
Reviewed-by: Dave Cheney <dave@cheney.net>
Reviewed-by: Russ Cox <rsc@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2015-03-16 18:46:35 +00:00
Ian Lance Taylor
362f7bfa68 test: add test that gccgo failed to compile
Change-Id: I9ea6d4d8a9c1c63de36f2f3871dd5ac9201c0aac
Reviewed-on: https://go-review.googlesource.com/7523
Reviewed-by: Minux Ma <minux@golang.org>
2015-03-13 22:05:23 +00:00
Shenghou Ma
0d6a0d6c3f runtime: don't return a slice with nil ptr but non-zero len from growslice
Fixes #10135.

Change-Id: Ic4c5ab15bcb7b9c3fcc685a788d3b59c60c26e1e
Signed-off-by: Shenghou Ma <minux@golang.org>
Reviewed-on: https://go-review.googlesource.com/7400
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2015-03-12 00:08:38 +00:00
Chris Manghane
09b49bf18d test: add testcase for gccgo-specific issue 10047.
Change-Id: Ia5115b15a79e1b2b53036646f1ed4b08225b220f
Reviewed-on: https://go-review.googlesource.com/7051
Run-TryBot: Chris Manghane <cmang@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2015-03-06 22:29:08 +00:00
Shenghou Ma
f09887cdce cmd/internal/gc: do not show original expression for constants in export data
Fixes #10066.

Change-Id: I43c423793dd094989e921e163a06b12181a35719
Signed-off-by: Shenghou Ma <minux@golang.org>
Reviewed-on: https://go-review.googlesource.com/6750
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Chris Manghane <cmang@golang.org>
2015-03-05 03:40:42 +00:00
Russ Cox
77ccb16eb1 cmd/internal/gc: transitive inlining
Inlining refuses to inline bodies containing an actual function call, so that
if that call or a child uses runtime.Caller it cannot observe
the inlining.

However, inlining was also refusing to inline bodies that contained
function calls that were themselves inlined away. For example:

	func f() int {
		return f1()
	}

	func f1() int {
		return f2()
	}

	func f2() int {
		return 2
	}

The f2 call in f1 would be inlined, but the f1 call in f would not,
because f1's call to f2 blocked the inlining, despite itself eventually
being inlined away.

Account properly for this kind of transitive inlining and enable.

Also bump the inlining budget a bit, so that the runtime's
heapBits.next is inlined.

This reduces the time for '6g *.go' in html/template by around 12% (!).
(For what it's worth, closing Chrome reduces the time by about 17%.)

Change-Id: If1aa673bf3e583082dcfb5f223e67355c984bfc1
Reviewed-on: https://go-review.googlesource.com/5952
Reviewed-by: Austin Clements <austin@google.com>
2015-02-26 17:36:00 +00:00
Chris Manghane
77d7771a82 cmd/internal/gc: omit non-explicit capacity in errors with map/chan make
Fixes #9083.

Change-Id: Ifbdebafb39a73a1dacf7e67171e8e88028d1f10b
Reviewed-on: https://go-review.googlesource.com/1219
Reviewed-by: Russ Cox <rsc@golang.org>
Run-TryBot: Chris Manghane <cmang@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2015-02-25 20:04:22 +00:00
Chris Manghane
c7e1453e3d cmd/internal/gc: do not show computed value in type error
Fixes #9076.

Change-Id: Ib41a452fa9aa9fecf19f65c36d13715923548041
Reviewed-on: https://go-review.googlesource.com/1250
Reviewed-by: Minux Ma <minux@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
Run-TryBot: Chris Manghane <cmang@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2015-02-25 19:49:49 +00:00
Chris Manghane
b59dd94f33 cmd/internal/gc: method selector should not auto-deref named pointer type
Fixes #9017.

Change-Id: I26cb1e7d6e137ff145773169cfe2d8bd4e1b339c
Reviewed-on: https://go-review.googlesource.com/1252
Reviewed-by: Russ Cox <rsc@golang.org>
Run-TryBot: Chris Manghane <cmang@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2015-02-25 19:27:30 +00:00
Russ Cox
5b94a47b7f [dev.cc] test: disable syntax error tests
These don't work with the new compiler, because the
new compiler doesn't have the custom syntax errors
that I built for the old compiler. It will, just not yet.
(Issue #9968.)

Change-Id: I658f7dab2c7f855340a501f9ae4479c097b28cd3
Reviewed-on: https://go-review.googlesource.com/5632
Reviewed-by: Rob Pike <r@golang.org>
2015-02-23 19:56:11 +00:00
Russ Cox
b4a7806724 [dev.cc] all: merge master (5868ce3) into dev.cc
This time for sure!

Change-Id: I7e7ea24edb7c2f711489e162fb97237a87533089
2015-02-20 10:28:36 -05:00
Russ Cox
d7eb51e70e [dev.cc] test: disable rotate tests
They use too much memory in the current Go compiler draft.
This should fix some builders.

Reenabling is #9933.

Change-Id: Ib5ef348b2c55d2012ffed765f2a6df99dec171f4
Reviewed-on: https://go-review.googlesource.com/5302
Reviewed-by: Russ Cox <rsc@golang.org>
2015-02-19 20:14:21 +00:00
Ian Lance Taylor
5aa448ff8c test: add test case for issue 4365
This is an update of http://golang.org/cl/151410043 by Tim Shen.

Change-Id: I43ab7fcedd785059c535f45a3c8cdb7b618c1499
Reviewed-on: https://go-review.googlesource.com/4873
Reviewed-by: David Crawshaw <crawshaw@golang.org>
2015-02-14 16:02:10 +00:00
Brad Fitzpatrick
b5b11bdbc6 test: deflake init1.go test, tighten its bounds
Per the comment at top, this test is about whether the GC runs during
init, but it was testing more than that, and testing how much the GC
collected in a certain amount of time.

Instead, loosen this test to just see whether it ran at all and not
how well it did.

Fixes #9848

Change-Id: I31da7dd769140d7b49aa6c149a543fae6076aa5e
Reviewed-on: https://go-review.googlesource.com/4820
Reviewed-by: Rick Hudson <rlh@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2015-02-13 22:13:56 +00:00
Dmitry Vyukov
c4ee44b7b9 cmd/gc: transform closure calls to function calls
Currently we always create context objects for closures that capture variables.
However, it is completely unnecessary for direct calls of closures
(whether it is func()(), defer func()() or go func()()).
This change transforms any OCALLFUNC(OCLOSURE) to normal function call.
Closed variables become function arguments.
This transformation is especially beneficial for go func(),
because we do not need to allocate context object on heap.
But it makes direct closure calls a bit faster as well (see BenchmarkClosureCall).

On implementation level it required to introduce yet another compiler pass.
However, the pass iterates only over xtop, so it should not be an issue.
Transformation consists of two parts: closure transformation and call site
transformation. We can't run these parts on different sides of escape analysis,
because tree state is inconsistent. We can do both parts during typecheck,
we don't know how to capture variables and don't have call site.
We can't do both parts during walk of OCALLFUNC, because we can walk
OCLOSURE body earlier.
So now capturevars pass only decides how to capture variables
(this info is required for escape analysis). New transformclosure
pass, that runs just before order/walk, does all transformations
of a closure. And later walk of OCALLFUNC(OCLOSURE) transforms call site.

benchmark                            old ns/op     new ns/op     delta
BenchmarkClosureCall                 4.89          3.09          -36.81%
BenchmarkCreateGoroutinesCapture     1634          1294          -20.81%

benchmark                            old allocs     new allocs     delta
BenchmarkCreateGoroutinesCapture     6              2              -66.67%

benchmark                            old bytes     new bytes     delta
BenchmarkCreateGoroutinesCapture     176           48            -72.73%

Change-Id: Ic85e1706e18c3235cc45b3c0c031a9c1cdb7a40e
Reviewed-on: https://go-review.googlesource.com/4050
Reviewed-by: Russ Cox <rsc@golang.org>
2015-02-13 12:12:18 +00:00
Josh Bleecher Snyder
77a2113925 cmd/gc: evaluate concrete == interface without allocating
Consider an interface value i of type I and concrete value c of type C.

Prior to this CL, i==c was evaluated as
	I(c) == i

Evaluating I(c) can allocate.

This CL changes the evaluation of i==c to
	x, ok := i.(C); ok && x == c

The new generated code is shorter and does not allocate directly.

If C is small, as it is in every instance in the stdlib,
the new code also uses less stack space
and makes one runtime call instead of two.

If C is very large, the original implementation is used.
The cutoff for "very large" is 1<<16,
following the stack vs heap cutoff used elsewhere.

This kind of comparison occurs in 38 places in the stdlib,
mostly in the net and os packages.

benchmark                     old ns/op     new ns/op     delta
BenchmarkEqEfaceConcrete      29.5          7.92          -73.15%
BenchmarkEqIfaceConcrete      32.1          7.90          -75.39%
BenchmarkNeEfaceConcrete      29.9          7.90          -73.58%
BenchmarkNeIfaceConcrete      35.9          7.90          -77.99%

Fixes #9370.

Change-Id: I7c4555950bcd6406ee5c613be1f2128da2c9a2b7
Reviewed-on: https://go-review.googlesource.com/2096
Reviewed-by: Russ Cox <rsc@golang.org>
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
2015-02-12 22:23:38 +00:00
Dmitry Vyukov
b3be360f16 cmd/gc: allocate non-escaping maps on stack
Extend escape analysis to make(map[k]v).
If it does not escape, allocate temp buffer for hmap and one bucket on stack.

There are 75 cases of non-escaping maps in std lib.

benchmark                                    old allocs     new allocs     delta
BenchmarkConcurrentStmtQuery                 16161          15161          -6.19%
BenchmarkConcurrentTxQuery                   17658          16658          -5.66%
BenchmarkConcurrentTxStmtQuery               16157          15156          -6.20%
BenchmarkConcurrentRandom                    13637          13114          -3.84%
BenchmarkManyConcurrentQueries               22             20             -9.09%
BenchmarkDecodeComplex128Slice               250            188            -24.80%
BenchmarkDecodeFloat64Slice                  250            188            -24.80%
BenchmarkDecodeInt32Slice                    250            188            -24.80%
BenchmarkDecodeStringSlice                   2250           2188           -2.76%
BenchmarkNewEmptyMap                         1              0              -100.00%
BenchmarkNewSmallMap                         2              0              -100.00%

benchmark                old ns/op     new ns/op     delta
BenchmarkNewEmptyMap     124           55.7          -55.08%
BenchmarkNewSmallMap     317           148           -53.31%

benchmark                old allocs     new allocs     delta
BenchmarkNewEmptyMap     1              0              -100.00%
BenchmarkNewSmallMap     2              0              -100.00%

benchmark                old bytes     new bytes     delta
BenchmarkNewEmptyMap     48            0             -100.00%
BenchmarkNewSmallMap     192           0             -100.00%

Fixes #5449

Change-Id: I24fa66f949d2f138885d9e66a0d160240dc9e8fa
Reviewed-on: https://go-review.googlesource.com/3508
Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: Dmitry Vyukov <dvyukov@google.com>
2015-02-12 09:53:52 +00:00
Dmitry Vyukov
9568126f35 cmd/gc: allocate buffers for non-escaping string conversions on stack
Support the following conversions in escape analysis:
[]rune("foo")
[]byte("foo")
string([]rune{})

If the result does not escape, allocate temp buffer on stack
and pass it to runtime functions.

Change-Id: I1d075907eab8b0109ad7ad1878104b02b3d5c690
Reviewed-on: https://go-review.googlesource.com/3590
Reviewed-by: Russ Cox <rsc@golang.org>
2015-02-12 08:29:53 +00:00
Josh Bleecher Snyder
4ce06f4b5c cmd/gc: eliminate dead code in switch statements
Ordinary switch statements are rewritten
into a sequence of if statements.
Staticly dead cases were not being eliminated
because the rewrite introduced a temporary,
which hid the fact that the case was a constant.
Stop doing that.

This eliminates dead code in the standard library at:

runtime/cgocall.go:219
runtime/cgocall.go:269
debug/gosym/pclntab.go:175
debug/macho/file.go:208
math/big/nat.go:635
math/big/nat.go:850
math/big/nat.go:1058
cmd/pprof/internal/commands/commands.go:86
net/sock_bsd.go:19
cmd/go/build.go:2657
cmd/go/env.go:90

Fixes #9608.

Change-Id: Ic23a05dfbb1ad91d5f62a6506b35a13e51b33e38
Reviewed-on: https://go-review.googlesource.com/3980
Reviewed-by: Keith Randall <khr@golang.org>
2015-02-06 19:05:47 +00:00
Péter Surányi
9b6ccb1323 all: don't refer to code.google.com/p/go{,-wiki}/
Only documentation / comment changes. Update references to
point to golang.org permalinks or go.googlesource.com/go.
References in historical release notes under doc are left as is.

Change-Id: Icfc14e4998723e2c2d48f9877a91c5abef6794ea
Reviewed-on: https://go-review.googlesource.com/4060
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2015-02-06 14:41:47 +00:00
Rahul Chaudhry
8581d48c15 test: check for build constraints only upto the first blank line
The main issue is that the misc/cgo/{stdio,life} tests are silently
getting skipped when invoked from run.bash.

run.go should ignore any build tags after the first blank line in
source file. It already checks for test actions only upto the first
blank line. Build tags must be specified in the same block.

See http://golang.org/cl/3675 for background.

Change-Id: Id8abf000119e3335f7250d8ef34aac7811fc9dff
Reviewed-on: https://go-review.googlesource.com/3812
Reviewed-by: Minux Ma <minux@golang.org>
2015-02-06 05:36:26 +00:00
Rahul Chaudhry
d81cc374be test: chdir before running go tool, cleanup afterwards.
issue9355 generated a file a.[568] in test/ directory and left it there.
For tests like these, it is best to chdir to a test specific directory
before generating any temporary files, since the tests are running
in parallel and might otherwise race with each other for the same files.

Change-Id: I58d96256d4d8ee3fda70d81077f19006064a7425
Reviewed-on: https://go-review.googlesource.com/3813
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2015-02-06 05:16:34 +00:00
Dmitry Vyukov
eaa872009d cmd/gc: fix capturing by value for range statements
Kindly detected by race builders by failing TestRaceRange.
ORANGE typecheck does not increment decldepth around body.

Change-Id: I0df5f310cb3370a904c94d9647a9cf0f15729075
Reviewed-on: https://go-review.googlesource.com/3507
Reviewed-by: Russ Cox <rsc@golang.org>
2015-02-03 15:48:48 +00:00
Dmitry Vyukov
8e2423a67d cmd/gc: typecheck type switch variables
Type switch variables was not typechecked.
Previously it lead only to a minor consequence:

switch unsafe.Sizeof = x.(type) {

generated an inconsistent error message.
But capturing by value functionality now requries typechecking of all ONAMEs.

Fixes #9731

Change-Id: If037883cba53d85028fb97b1328696091b3b7ddd
Reviewed-on: https://go-review.googlesource.com/3600
Reviewed-by: Russ Cox <rsc@golang.org>
2015-02-03 15:44:06 +00:00
Austin Clements
3c0fee10db cmd/6g, liblink, runtime: support saving base pointers
This adds a "framepointer" GOEXPERIMENT that that makes the amd64
toolchain maintain base pointer chains in the same way that gcc
-fno-omit-frame-pointer does.  Go doesn't use these saved base
pointers, but this does enable external tools like Linux perf and
VTune to unwind Go stacks when collecting system-wide profiles.

This requires support in the compilers to not clobber BP, support in
liblink for generating the BP-saving function prologue and unwinding
epilogue, and support in the runtime to save BPs across preemption, to
skip saved BPs during stack unwinding and, and to adjust saved BPs
during stack moving.

As with other GOEXPERIMENTs, everything from the toolchain to the
runtime must be compiled with this experiment enabled.  To do this,
run make.bash (or all.bash) with GOEXPERIMENT=framepointer.

Change-Id: I4024853beefb9539949e5ca381adfdd9cfada544
Reviewed-on: https://go-review.googlesource.com/2992
Reviewed-by: Russ Cox <rsc@golang.org>
2015-02-02 19:36:05 +00:00
Shenghou Ma
3bf005cea3 cmd/gc: always treat the output parameters as having been assigned in capturevars.
Fixes #9738.

Change-Id: Iab75de2d78335d4e31c3dce6a0e1826d8cddf5f3
Reviewed-on: https://go-review.googlesource.com/3690
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
2015-02-02 14:14:21 +00:00
Robert Griesemer
4a1756824f test/closure2.go: correctly "use" tmp
cmd/go doesn't complain (this is an open issue), but go/types does

Change-Id: I2caec1f7aec991a9500d2c3504c29e4ab718c138
Reviewed-on: https://go-review.googlesource.com/3541
Reviewed-by: Alan Donovan <adonovan@google.com>
2015-01-29 22:22:14 +00:00
Dmitry Vyukov
0e80b2e082 cmd/gc: capture variables by value
Language specification says that variables are captured by reference.
And that is what gc compiler does. However, in lots of cases it is
possible to capture variables by value under the hood without
affecting visible behavior of programs. For example, consider
the following typical pattern:

	func (o *Obj) requestMany(urls []string) []Result {
		wg := new(sync.WaitGroup)
		wg.Add(len(urls))
		res := make([]Result, len(urls))
		for i := range urls {
			i := i
			go func() {
				res[i] = o.requestOne(urls[i])
				wg.Done()
			}()
		}
		wg.Wait()
		return res
	}

Currently o, wg, res, and i are captured by reference causing 3+len(urls)
allocations (e.g. PPARAM o is promoted to PPARAMREF and moved to heap).
But all of them can be captured by value without changing behavior.

This change implements simple strategy for capturing by value:
if a captured variable is not addrtaken and never assigned to,
then it is captured by value (it is effectively const).
This simple strategy turned out to be very effective:
~80% of all captures in std lib are turned into value captures.
The remaining 20% are mostly in defers and non-escaping closures,
that is, they do not cause allocations anyway.

benchmark                                    old allocs     new allocs     delta
BenchmarkCompressedZipGarbage                153            126            -17.65%
BenchmarkEncodeDigitsSpeed1e4                91             69             -24.18%
BenchmarkEncodeDigitsSpeed1e5                178            129            -27.53%
BenchmarkEncodeDigitsSpeed1e6                1510           1051           -30.40%
BenchmarkEncodeDigitsDefault1e4              100            75             -25.00%
BenchmarkEncodeDigitsDefault1e5              193            139            -27.98%
BenchmarkEncodeDigitsDefault1e6              1420           985            -30.63%
BenchmarkEncodeDigitsCompress1e4             100            75             -25.00%
BenchmarkEncodeDigitsCompress1e5             193            139            -27.98%
BenchmarkEncodeDigitsCompress1e6             1420           985            -30.63%
BenchmarkEncodeTwainSpeed1e4                 109            81             -25.69%
BenchmarkEncodeTwainSpeed1e5                 211            151            -28.44%
BenchmarkEncodeTwainSpeed1e6                 1588           1097           -30.92%
BenchmarkEncodeTwainDefault1e4               103            77             -25.24%
BenchmarkEncodeTwainDefault1e5               199            143            -28.14%
BenchmarkEncodeTwainDefault1e6               1324           917            -30.74%
BenchmarkEncodeTwainCompress1e4              103            77             -25.24%
BenchmarkEncodeTwainCompress1e5              190            137            -27.89%
BenchmarkEncodeTwainCompress1e6              1327           919            -30.75%
BenchmarkConcurrentDBExec                    16223          16220          -0.02%
BenchmarkConcurrentStmtQuery                 17687          16182          -8.51%
BenchmarkConcurrentStmtExec                  5191           5186           -0.10%
BenchmarkConcurrentTxQuery                   17665          17661          -0.02%
BenchmarkConcurrentTxExec                    15154          15150          -0.03%
BenchmarkConcurrentTxStmtQuery               17661          16157          -8.52%
BenchmarkConcurrentTxStmtExec                3677           3673           -0.11%
BenchmarkConcurrentRandom                    14000          13614          -2.76%
BenchmarkManyConcurrentQueries               25             22             -12.00%
BenchmarkDecodeComplex128Slice               318            252            -20.75%
BenchmarkDecodeFloat64Slice                  318            252            -20.75%
BenchmarkDecodeInt32Slice                    318            252            -20.75%
BenchmarkDecodeStringSlice                   2318           2252           -2.85%
BenchmarkDecode                              11             8              -27.27%
BenchmarkEncodeGray                          64             56             -12.50%
BenchmarkEncodeNRGBOpaque                    64             56             -12.50%
BenchmarkEncodeNRGBA                         67             58             -13.43%
BenchmarkEncodePaletted                      68             60             -11.76%
BenchmarkEncodeRGBOpaque                     64             56             -12.50%
BenchmarkGoLookupIP                          153            139            -9.15%
BenchmarkGoLookupIPNoSuchHost                508            466            -8.27%
BenchmarkGoLookupIPWithBrokenNameServer      245            226            -7.76%
BenchmarkClientServer                        62             59             -4.84%
BenchmarkClientServerParallel4               62             59             -4.84%
BenchmarkClientServerParallel64              62             59             -4.84%
BenchmarkClientServerParallelTLS4            79             76             -3.80%
BenchmarkClientServerParallelTLS64           112            109            -2.68%
BenchmarkCreateGoroutinesCapture             10             6              -40.00%
BenchmarkAfterFunc                           1006           1005           -0.10%

Fixes #6632.

Change-Id: I0cd51e4d356331d7f3c5f447669080cd19b0d2ca
Reviewed-on: https://go-review.googlesource.com/3166
Reviewed-by: Russ Cox <rsc@golang.org>
2015-01-29 13:07:30 +00:00
Dmitry Vyukov
4ce4d8b2c4 cmd/gc: allocate stack buffer for ORUNESTR
If result of string(i) does not escape,
allocate a [4]byte temp on stack for it.

Change-Id: If31ce9447982929d5b3b963fd0830efae4247c37
Reviewed-on: https://go-review.googlesource.com/3411
Reviewed-by: Russ Cox <rsc@golang.org>
2015-01-28 20:37:20 +00:00
Dmitry Vyukov
e6fac08146 cmd/gc: allocate buffers for non-escaped strings on stack
Currently we always allocate string buffers in heap.
For example, in the following code we allocate a temp string
just for comparison:

	if string(byteSlice) == "abc" { ... }

This change extends escape analysis to cover []byte->string
conversions and string concatenation. If the result of operations
does not escape, compiler allocates a small buffer
on stack and passes it to slicebytetostring and concatstrings.
Then runtime uses the buffer if the result fits into it.

Size of the buffer is 32 bytes. There is no fundamental theory
behind this number. Just an observation that on std lib
tests/benchmarks frequency of string allocation is inversely
proportional to string length; and there is significant number
of allocations up to length 32.

benchmark                                    old allocs     new allocs     delta
BenchmarkFprintfBytes                        2              1              -50.00%
BenchmarkDecodeComplex128Slice               318            316            -0.63%
BenchmarkDecodeFloat64Slice                  318            316            -0.63%
BenchmarkDecodeInt32Slice                    318            316            -0.63%
BenchmarkDecodeStringSlice                   2318           2316           -0.09%
BenchmarkStripTags                           11             5              -54.55%
BenchmarkDecodeGray                          111            102            -8.11%
BenchmarkDecodeNRGBAGradient                 200            188            -6.00%
BenchmarkDecodeNRGBAOpaque                   165            152            -7.88%
BenchmarkDecodePaletted                      319            309            -3.13%
BenchmarkDecodeRGB                           166            157            -5.42%
BenchmarkDecodeInterlacing                   279            268            -3.94%
BenchmarkGoLookupIP                          153            135            -11.76%
BenchmarkGoLookupIPNoSuchHost                508            466            -8.27%
BenchmarkGoLookupIPWithBrokenNameServer      245            226            -7.76%
BenchmarkClientServerParallel4               62             61             -1.61%
BenchmarkClientServerParallel64              62             61             -1.61%
BenchmarkClientServerParallelTLS4            79             78             -1.27%
BenchmarkClientServerParallelTLS64           112            111            -0.89%

benchmark                                    old ns/op      new ns/op      delta
BenchmarkFprintfBytes                        381            311            -18.37%
BenchmarkStripTags                           2615           2351           -10.10%
BenchmarkDecodeNRGBAGradient                 3715887        3635096        -2.17%
BenchmarkDecodeNRGBAOpaque                   3047645        2928644        -3.90%
BenchmarkGoLookupIP                          153            135            -11.76%
BenchmarkGoLookupIPNoSuchHost                508            466            -8.27%

Change-Id: I9ec01da816945c3329d7be3c7794b520418c3f99
Reviewed-on: https://go-review.googlesource.com/3120
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2015-01-28 20:12:38 +00:00
Dmitry Vyukov
22c16b4b92 cmd/gc: ignore re-slicing in escape analysis
Escape analysis treats everything assigned to OIND/ODOTPTR as escaping.
As the result b escapes in the following code:

	func (b *Buffer) Foo() {
		n, m := ...
		b.buf = b.buf[n:m]
	}

This change recognizes such assignments and ignores them.

Update issue #9043.
Update issue #7921.

There are two similar cases in std lib that benefit from this optimization.
First is in archive/zip:

type readBuf []byte
func (b *readBuf) uint32() uint32 {
	v := binary.LittleEndian.Uint32(*b)
	*b = (*b)[4:]
	return v
}

Second is in time:

type data struct {
	p     []byte
	error bool
}

func (d *data) read(n int) []byte {
	if len(d.p) < n {
		d.p = nil
		d.error = true
		return nil
	}
	p := d.p[0:n]
	d.p = d.p[n:]
	return p
}

benchmark                         old ns/op     new ns/op     delta
BenchmarkCompressedZipGarbage     32431724      32217851      -0.66%

benchmark                         old allocs     new allocs     delta
BenchmarkCompressedZipGarbage     153            143            -6.54%

Change-Id: Ia6cd32744e02e36d6d8c19f402f8451101711626
Reviewed-on: https://go-review.googlesource.com/3162
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2015-01-28 17:37:55 +00:00
Dmitry Vyukov
1b87f01239 cmd/gc: improve escape analysis for &T{...}
Currently all PTRLIT element initializers escape. There is no reason for that.
This change links STRUCTLIT to PTRLIT; STRUCTLIT element initializers are
already linked to the STRUCTLIT. As the result, PTRLIT element initializers
escape when PTRLIT itself escapes.

Change-Id: I89ecd8677cbf81addcfd469cd2fd461c0e9bf7dd
Reviewed-on: https://go-review.googlesource.com/3031
Reviewed-by: Russ Cox <rsc@golang.org>
2015-01-28 16:59:01 +00:00
Dmitry Vyukov
b581ca5956 cmd/gc: allow map index expressions in for range statements
Fixes #9691.

Change-Id: I22bfc82e05497e91a7b18a668913aed6c723365d
Reviewed-on: https://go-review.googlesource.com/3282
Reviewed-by: Russ Cox <rsc@golang.org>
2015-01-28 15:14:04 +00:00
Ian Lance Taylor
ec0ebc2281 cmd/gc: treat non-local vars inlined into wrapper as escaping
The compiler has a phase ordering problem.  Escape analysis runs
before wrapper generation.  When a generated wrapper calls a method
defined in a different package, if that call is inlined, there will be
no escape information for the variables defined in the inlined call.
Those variables will be placed on the stack, which fails if they
actually do escape.

There are probably various complex ways to fix this.  This is a simple
way to avoid it: when a generated wrapper calls a method defined in a
different package, treat all local variables as escaping.

Fixes #9537.

Change-Id: I530f39346de16ad173371c6c3f69cc189351a4e9
Reviewed-on: https://go-review.googlesource.com/3092
Reviewed-by: Russ Cox <rsc@golang.org>
2015-01-22 03:25:12 +00:00
Chris Manghane
f5b8813e93 cmd/gc: don't unpack struct arguments to append
Fixes #9634.

Change-Id: I7b18f26c2fb812978fc7adc5bfd39ebfffe48701
Reviewed-on: https://go-review.googlesource.com/3080
Reviewed-by: Minux Ma <minux@golang.org>
2015-01-20 22:55:56 +00:00
Keith Randall
c3b459d328 test: generate tests for arithmetic on narrow types
Fixes #9607
Related to #9604
Inadvertently found #9609

Change-Id: I8a8ddf84ac72d3e18986fd8e9288734459f3f174
Reviewed-on: https://go-review.googlesource.com/2962
Reviewed-by: Minux Ma <minux@golang.org>
2015-01-17 21:00:15 +00:00
Keith Randall
daa64ddfe6 cmd/5g: make sure we normalize after unary ops on small types
We were failing ^uint16(0xffff) == 0, as we computed 0xffff0000 instead.

I could only trigger a failure for the above case, the other two tests
^uint16(0xfffe) == 1 and -uint16(0xffff) == 1 didn't seem to fail
previously.  Somehow they get MOVHUs inserted for other reasons (used
by CMP instead of TST?).  I fixed OMINUS anyway, better safe than
sorry.

Fixes #9604

Change-Id: I4c2d5bdc667742873ac029fdbe3db0cf12893c27
Reviewed-on: https://go-review.googlesource.com/2940
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Minux Ma <minux@golang.org>
2015-01-15 23:50:01 +00:00
Rob Pike
3b63b69d2f test: comment the behavior and use of cmplxdivide*
The various files are confusingly named and their operation
not easy to see. Add a comment to cmplxdivide.c, one of the few
C files that will endure in the repository, to explain how to build
and run the test.

Change-Id: I1fd5c564a14217e1b9815b09bc24cc43c54c096f
Reviewed-on: https://go-review.googlesource.com/2850
Reviewed-by: Russ Cox <rsc@golang.org>
2015-01-15 00:00:06 +00:00
Shenghou Ma
fcff3ba740 cmd/gc: don't recurse infinitely when a recursive type references itself more than once
Fixes #9432

Change-Id: I08c92481afa7c7fac890aa780efc1cb2fabad528
Reviewed-on: https://go-review.googlesource.com/2115
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Russ Cox <rsc@golang.org>
2015-01-12 02:09:50 +00:00
Josh Bleecher Snyder
f03c9202c4 cmd/gc: optimize memclr of slices and arrays
Recognize loops of the form

for i := range a {
	a[i] = zero
}

in which the evaluation of a is free from side effects.
Replace these loops with calls to memclr.
This occurs in the stdlib in 18 places.

The motivating example is clearing a byte slice:

benchmark                old ns/op     new ns/op     delta
BenchmarkGoMemclr5       3.31          3.26          -1.51%
BenchmarkGoMemclr16      13.7          3.28          -76.06%
BenchmarkGoMemclr64      50.8          4.14          -91.85%
BenchmarkGoMemclr256     157           6.02          -96.17%

Update #5373.

Change-Id: I99d3e6f5f268e8c6499b7e661df46403e5eb83e4
Reviewed-on: https://go-review.googlesource.com/2520
Reviewed-by: Keith Randall <khr@golang.org>
2015-01-09 22:35:25 +00:00
Rick Hudson
db7fd1c142 runtime: increase GC concurrency.
run GC in its own background goroutine making the
caller runnable if resources are available. This is
critical in single goroutine applications.
Allow goroutines that allocate a lot to help out
the GC and in doing so throttle their own allocation.
Adjust test so that it only detects that a GC is run
during init calls and not whether the GC is memory
efficient. Memory efficiency work will happen later
in 1.5.

Change-Id: I4306f5e377bb47c69bda1aedba66164f12b20c2b
Reviewed-on: https://go-review.googlesource.com/2349
Reviewed-by: Russ Cox <rsc@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
2015-01-08 20:34:56 +00:00
Keith Randall
fcfbeb3adf test: shorten test runtime
This test was taking a long time, reduce its zealousness.

Change-Id: Ib824247b84b0039a9ec690f72336bef3738d4c44
Reviewed-on: https://go-review.googlesource.com/2502
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Minux Ma <minux@golang.org>
2015-01-08 04:49:43 +00:00
Josh Bleecher Snyder
43e6923131 cmd/gc: optimize existence-only map lookups
The compiler converts 'val, ok = m[key]' to

        tmp, ok = <runtime call>
        val = *tmp

For lookups of the form '_, ok = m[key]',
the second statement is unnecessary.
By not generating it we save a nil check.

Change-Id: I21346cc195cb3c62e041af8b18770c0940358695
Reviewed-on: https://go-review.googlesource.com/1975
Reviewed-by: Russ Cox <rsc@golang.org>
2015-01-07 22:36:06 +00:00
Josh Bleecher Snyder
60801c4853 test: delete testlib
It is unused as of e7173dfd.

Change-Id: I3e4ea3fc66cf0a768ff28172a151b244952eefc9
Reviewed-on: https://go-review.googlesource.com/2093
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2015-01-07 21:48:48 +00:00
Matthew Dempsky
537ddc9456 runtime: fix slicecopy return value for zero-width elements
Fixes #8620

Change-Id: Idb49e586919d21d07e94a39ed9ebb0562f403460
Reviewed-on: https://go-review.googlesource.com/2221
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2015-01-04 01:59:59 +00:00
Josh Bleecher Snyder
8bbd80063b cmd/go: put user ldflags at the end of the linker invocation
If the user provided a key but no value via -ldflag -X,
another linker flag was used as the value.

Placing the user's flags at the end avoids this problem.
It also provides the user the opportunity to
override existing linker flags.

Fixes #8810.

Change-Id: I96f4190713dc9a9c29142e56658446fba7fb6bc8
Reviewed-on: https://go-review.googlesource.com/2242
Reviewed-by: Minux Ma <minux@golang.org>
2015-01-02 18:36:44 +00:00
Shenghou Ma
cb1897a58c cmd/gc: give an error if only one argument is given to complex()
Fixes #8501

Change-Id: I0dbbdded7f7924351c3d1841d60cb5c934b295b7
Reviewed-on: https://go-review.googlesource.com/2143
Reviewed-by: Chris Manghane <cmang@golang.org>
2015-01-02 02:52:56 +00:00
Chris Manghane
5cc29ab95e cmd/gc: logical operators should produce untyped bool for untyped
operands

Fixes #6671 for cmd/gc.

Change-Id: I4907655b6e243960f2ceb544c63ea16513c7bd68
Reviewed-on: https://go-review.googlesource.com/1251
Reviewed-by: Robert Griesemer <gri@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2014-12-29 23:36:30 +00:00
Chris Manghane
edf7258416 test: add fixed GoSmith bugs reported on the gcc Bugzilla
Change-Id: I36b57f3e299a4f96b8b5aa55c9c224d888229684
Reviewed-on: https://go-review.googlesource.com/1790
Reviewed-by: Minux Ma <minux@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2014-12-29 23:21:10 +00:00
Shenghou Ma
958e0792b5 test/fixedbugs/issue9355: fix build on arm and power64
Change-Id: I1ef770184ad1d42bcb58714d559f2cc866a919ab
Signed-off-by: Shenghou Ma <minux@golang.org>
Reviewed-on: https://go-review.googlesource.com/1880
Reviewed-by: Keith Randall <khr@golang.org>
2014-12-24 00:07:46 +00:00
David du Colombier
fbdf59a7c4 test: disable bug248 and bug345 tests on Plan 9
These tests were enabled as part of change 1774.
They depend on the errchk tool, which is a Perl
script. However, Perl is not available on Plan 9.

Change-Id: I82707aae16013acc9a3800d39b0084588b852b53
Reviewed-on: https://go-review.googlesource.com/2031
Reviewed-by: Minux Ma <minux@golang.org>
2014-12-23 10:28:39 +00:00
Josh Bleecher Snyder
209dd4cdc1 test: fix windows build
Broken by e7173dfdfd

Fix by simply disabling the relevant tests.

* bug248 and bug345 require errchk, but we can't
  rely on perl being available.
* bug369 is disabled anyway.

Change-Id: Idf73ebccb066943e3fe17c2f662b37238ec74dfe
Reviewed-on: https://go-review.googlesource.com/2052
Reviewed-by: Alex Brainman <alex.brainman@gmail.com>
2014-12-23 01:12:30 +00:00
Ian Lance Taylor
02f56bfb5c test: add test case that gccgo failed to link
Gccgo creates a struct to hold the arguments for the deferred
function.  In this example the struct holds a type defined in a
different package.  The bug was that gccgo tried to create an equality
function for this struct, and it implemented that function by calling
the equality function for the type defined in the other package.
Since that type is not exported, the reference to the equality
function failed at link time.  Normally it is impossible for a struct
to directly contain a member that is an unexported type from another
package, but in this specific case it was possible.  Fixed in gccgo
with https://codereview.appspot.com/183500043 .

Change-Id: I8ec3a33631225b9ac2a4ac060cb4d10b4635e60b
Reviewed-on: https://go-review.googlesource.com/1690
Reviewed-by: Russ Cox <rsc@golang.org>
Reviewed-by: Minux Ma <minux@golang.org>
2014-12-22 23:07:10 +00:00
Josh Bleecher Snyder
e7173dfdfd test: migrate remaining tests to run.go
* bug248, bug345, bug369, and bug429 were ported from bash commands to run scripts. bug369 remains disabled.
* bug395 is a test for issue 1909, which is still open. It is marked as skip now and will be usable with compile with run.go when issue 1909 is fixed.

Fixes #4139

Updates #1909

Change-Id: Ibb5fbfb5cf72ddc285829245318eeacd3fb5a636
Reviewed-on: https://go-review.googlesource.com/1774
Reviewed-by: Russ Cox <rsc@golang.org>
2014-12-22 22:41:34 +00:00
Shenghou Ma
c5089a7a81 test/fixedbugs/issue9355: fix build on windows and skip on nacl
Change-Id: If367cc1e8c2d744569513bc71da6e6c454c74e9a
Signed-off-by: Shenghou Ma <minux@golang.org>
Reviewed-on: https://go-review.googlesource.com/1802
Reviewed-by: Alex Brainman <alex.brainman@gmail.com>
2014-12-19 01:06:33 +00:00
Keith Randall
2fc29a83ae cmd/gc: resolve static addresses of the form &x.f at link time
When we do y = &x for global variables x and y, y gets initialized
at link time.  Do the same for y = &x.f if x is a struct and y=&x[5]
if x is an array.

fixes #9217
fixes #9355

Change-Id: Iea3c0ce2ce1b309e2b760e345608fd95460b5713
Reviewed-on: https://go-review.googlesource.com/1691
Reviewed-by: Minux Ma <minux@golang.org>
2014-12-18 21:53:03 +00:00
Josh Bleecher Snyder
8e0686a071 test: add missing linkx test
This test was added in CL 151000043.
It got lost in CL 144630044.

Change-Id: I318ab11be8e3e7489fc1395457c029c8bdb2aa41
Reviewed-on: https://go-review.googlesource.com/1773
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2014-12-18 17:41:27 +00:00
Ian Lance Taylor
6cd4d59db6 test: add bug494: test case miscompiled by gccgo
Gccgo incorrectly executed functions multiple times when they appeared
in a composite literal that required a conversion between different
interface types.

Change-Id: I7b40e76ed23fa8440ffa03b262041265c109adf7
Reviewed-on: https://go-review.googlesource.com/1710
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Minux Ma <minux@golang.org>
2014-12-18 02:45:00 +00:00
Ian Lance Taylor
60ea2c594b test: add test that gccgo failed to compile
Gccgo failed to create the type descriptor for the type used to
allocate the nil value passed to append as the second argument when
append is called with only one argument.  Calling append with only one
argument is unusual but obviously should not cause a compiler crash.

Change-Id: I530821847dfd68f0302de6ca6a84dfbc79653935
Reviewed-on: https://go-review.googlesource.com/1692
Reviewed-by: Minux Ma <minux@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2014-12-17 02:22:57 +00:00
Keith Randall
50bc3d5bbc runtime: fix deadlock in runtime.Stack
It shouldn't semacquire() inside an acquirem(), the runtime
thinks that means deadlock.  It actually isn't a deadlock, but it
looks like it because acquirem() does m.locks++.

Candidate for inclusion in 1.4.1.  runtime.Stack with all=true
is pretty unuseable in GOMAXPROCS>1 environment.

fixes #9321

Change-Id: Iac6b664217d24763b9878c20e49229a1ecffc805
Reviewed-on: https://go-review.googlesource.com/1600
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
2014-12-16 17:04:45 +00:00
Shenghou Ma
e8f13700b7 test/fixedbugs/bug302: fix test on windows.
Change-Id: I74c2578d1620b37a6486eca00a774b9a736a8899
Reviewed-on: https://go-review.googlesource.com/1222
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2014-12-09 05:23:35 +00:00
Ian Lance Taylor
c5de72b213 test: write Go wrapper code so that bug302 can be run by run.go
Issue #4139.

Change-Id: I50d85a65b22c0cfb4d2a078cee45cf7adb23ba77
Reviewed-on: https://go-review.googlesource.com/1210
Reviewed-by: Russ Cox <rsc@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
2014-12-09 01:07:27 +00:00
Robert Griesemer
779682107f Fix whitespace (use blanks consistently).
Change-Id: I73ecfe8f1e46e4821dafc6ed5788f48a1f0deeea
Reviewed-on: https://go-review.googlesource.com/1213
Reviewed-by: Alan Donovan <adonovan@google.com>
2014-12-08 22:22:58 +00:00
Keith Randall
212914f573 runtime: test for linear enqueue/dequeue behavior
Make sure dequeueing from a channel queue does not exhibit quadratic time behavior.

Change-Id: Ifb7c709b026f74c7e783610d4914dd92909a441b
Reviewed-on: https://go-review.googlesource.com/1212
Reviewed-by: Russ Cox <rsc@golang.org>
2014-12-08 22:18:17 +00:00
Robert Griesemer
8d5fe682b0 test/fibo: a stand-alone bignum/allocation benchmark and test
Usage:
fibo <n>        compute fibonacci(n), n must be >= 0
fibo -bench     benchmark fibonacci computation (takes about 1 min)

Additional flags:
-half           add values using two half-digit additions
-opt            optimize memory allocation through reuse
-short          only print the first 10 digits of very large fibonacci numbers

This change was reviewed in detail as https://codereview.appspot.com/168480043 .

Change-Id: I7c86d49c5508532ea6206d00f424cf2117d2fe41
Reviewed-on: https://go-review.googlesource.com/1211
Reviewed-by: Russ Cox <rsc@golang.org>
2014-12-08 20:57:31 +00:00
Russ Cox
31457cef6d all: merge dev.garbage (d1238958d4ae) into default branch
When we start work on Gerrit, ppc64 and garbage collection
work will continue in the master branch, not the dev branches.

(We may still use dev branches for other things later, but
these are ready to be merged, and doing it now, before moving
to Git means we don't have to have dev branches working
in the Gerrit workflow on day one.)

TBR=rlh
CC=golang-codereviews
https://golang.org/cl/183140043
2014-12-05 20:34:45 -05:00
Russ Cox
db40624110 [dev.garbage] runtime: raise StackGuard limit for Windows (again)
640 bytes ought to be enough for anybody.

We'll bring this back down before Go 1.5. That's issue 9214.

TBR=rlh
CC=golang-codereviews
https://golang.org/cl/188730043
2014-12-05 19:50:09 -05:00
Russ Cox
09d92b6bbf all: power64 is now ppc64
Fixes #8654.

LGTM=austin
R=austin
CC=golang-codereviews
https://golang.org/cl/180600043
2014-12-05 19:13:20 -05:00
Russ Cox
b8540fc288 [dev.garbage] all: merge dev.cc (493ad916c3b1) into dev.garbage
TBR=austin
CC=golang-codereviews
https://golang.org/cl/179290043
2014-11-24 12:07:11 -05:00
Russ Cox
50e0749f87 [dev.cc] all: merge default (e4ab8f908aac) into dev.cc
TBR=austin
CC=golang-codereviews
https://golang.org/cl/179040044
2014-11-20 11:48:08 -05:00