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2811 Commits

Author SHA1 Message Date
Robert Griesemer
912a638b0c cmd/compile: check labels and branches during parse time
Instead of a separate check control flow pass (checkcfg.go)
operating on nodes, perform this check at parse time on the
new syntax tree. Permits this check to be done concurrently,
and doesn't depend on the specifics of the symbol's dclstack
implementation anymore. The remaining dclstack uses will be
removed in a follow-up change.

- added CheckBranches Mode flag (so we can turn off the check
  if we only care about syntactic correctness, e.g. for tests)

- adjusted test/goto.go error messages: the new branches
  checker only reports if a goto jumps into a block, but not
  which block (we may want to improve this again, eventually)

- also, the new branches checker reports one variable that
  is being jumped over by a goto, but it may not be the first
  one declared (this is fine either way)

- the new branches checker reports additional errors for
  fixedbugs/issue14006.go (not crucial to avoid those errors)

- the new branches checker now correctly reports only
  variable declarations being jumped over, rather than
  all declarations (issue 8042). Added respective tests.

Fixes #8042.

Change-Id: I53b6e1bda189748e1e1fb5b765a8a64337c27d40
Reviewed-on: https://go-review.googlesource.com/39998
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2017-04-19 00:36:34 +00:00
Matthew Dempsky
1e3570ac86 cmd/internal/objabi: extract shared functionality from obj
Now only cmd/asm and cmd/compile depend on cmd/internal/obj. Changing
the assembler backends no longer requires reinstalling cmd/link or
cmd/addr2line.

There's also now one canonical definition of the object file format in
cmd/internal/objabi/doc.go, with a warning to update all three
implementations.

objabi is still something of a grab bag of unrelated code (e.g., flag
and environment variable handling probably belong in a separate "tool"
package), but this is still progress.

Fixes #15165.
Fixes #20026.

Change-Id: Ic4b92fac7d0d35438e0d20c9579aad4085c5534c
Reviewed-on: https://go-review.googlesource.com/40972
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
2017-04-19 00:00:09 +00:00
David Lazar
0ea120a70c runtime: skip logical frames in runtime.Caller
This rewrites runtime.Caller in terms of stackExpander, which already
handles inlined frames and partially skipped frames. This also has the
effect of making runtime.Caller understand cgo frames if there is a cgo
symbolizer.

Updates #19348.

Change-Id: Icdf4df921aab5aa394d4d92e3becc4dd169c9a6e
Reviewed-on: https://go-review.googlesource.com/40270
Run-TryBot: David Lazar <lazard@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
2017-04-18 19:56:30 +00:00
Josh Bleecher Snyder
dffe5ac9f2 cmd/compile: eliminate dead code in if statements after typechecking
This is a more thorough and cleaner fix
than doing dead code elimination separately
during inlining, escape analysis, and export.

Unfortunately, it does add another full walk of the AST.
The performance impact is very small, but not non-zero.

If a label or goto is present in the dead code, it is not eliminated.
This restriction can be removed once label/goto checking occurs
much earlier in the compiler. In practice, it probably doesn't
matter much.

Updates #19699
Fixes #19705

name       old alloc/op      new alloc/op      delta
Template        39.2MB ± 0%       39.3MB ± 0%  +0.28%  (p=0.008 n=5+5)
Unicode         29.8MB ± 0%       29.8MB ± 0%    ~     (p=1.000 n=5+5)
GoTypes          113MB ± 0%        113MB ± 0%  -0.55%  (p=0.008 n=5+5)
SSA             1.25GB ± 0%       1.25GB ± 0%  +0.02%  (p=0.008 n=5+5)
Flate           25.3MB ± 0%       25.3MB ± 0%  -0.24%  (p=0.032 n=5+5)
GoParser        31.7MB ± 0%       31.8MB ± 0%  +0.31%  (p=0.008 n=5+5)
Reflect         78.2MB ± 0%       78.3MB ± 0%    ~     (p=0.421 n=5+5)
Tar             26.6MB ± 0%       26.7MB ± 0%  +0.21%  (p=0.008 n=5+5)
XML             42.2MB ± 0%       42.2MB ± 0%    ~     (p=0.056 n=5+5)

name       old allocs/op     new allocs/op     delta
Template          385k ± 0%         387k ± 0%  +0.51%  (p=0.016 n=5+5)
Unicode           321k ± 0%         321k ± 0%    ~     (p=1.000 n=5+5)
GoTypes          1.14M ± 0%        1.14M ± 0%    ~     (p=1.000 n=5+5)
SSA              9.71M ± 0%        9.72M ± 0%  +0.10%  (p=0.008 n=5+5)
Flate             234k ± 1%         234k ± 1%    ~     (p=0.690 n=5+5)
GoParser          315k ± 0%         317k ± 0%  +0.71%  (p=0.008 n=5+5)
Reflect           980k ± 0%         983k ± 0%  +0.30%  (p=0.032 n=5+5)
Tar               251k ± 0%         252k ± 0%  +0.55%  (p=0.016 n=5+5)
XML               392k ± 0%         393k ± 0%  +0.30%  (p=0.008 n=5+5)

Change-Id: Ia10ff4bbf5c6eae782582cc9cbc9785494d4fb83
Reviewed-on: https://go-review.googlesource.com/38773
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2017-04-18 17:13:30 +00:00
Alberto Donizetti
6266b0f08f cmd/compile: add test for Issue 12536
The fixedbugs/issue12536.go file was erroneously deleted just before
committing the patch that fixed the issue (CL 14400).

That's an easy test and there's a small reproducer in the issue, add
it back.

Updates #12536

Change-Id: Ib7b0cd245588299e9a5469e1d75805fd0261ce1a
Reviewed-on: https://go-review.googlesource.com/40712
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2017-04-14 14:16:09 +00:00
Brad Fitzpatrick
dc09a7af2e test: disable flaky test/fixedbugs/issue10958.go
Updates #18589

Change-Id: I2c3bbc8257c68295051bd2e63e1e11794d0609c3
Reviewed-on: https://go-review.googlesource.com/40651
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-04-13 18:28:29 +00:00
Alberto Donizetti
2e60882fc7 cmd/compile: do not print duplicate error on ideal->float{32,64} overflow
Also adjust truncfltlit to make it more similar to trunccmplxlit, and
make it report an error for bad Etypes.

Fixes #19947

Change-Id: I6684523e989c2293b8a8e85bd2bfb9c399c5ea36
Reviewed-on: https://go-review.googlesource.com/40453
Reviewed-by: Robert Griesemer <gri@golang.org>
2017-04-12 21:00:15 +00:00
Alberto Donizetti
10a200e560 cmd/compile: diagnose constant division by complex zero
When casting an ideal to complex{64,128}, for example during the
evaluation of

  var a = complex64(0) / 1e-50

we want the compiler to report a division-by-zero error if a divisor
would be zero after the cast.

We already do this for floats; for example

  var b = float32(0) / 1e-50

generates a 'division by zero' error at compile time (because
float32(1e-50) is zero, and the cast is done before performing the
division).

There's no such check in the path for complex{64,128} expressions, and
no cast is performed before the division in the evaluation of

  var a = complex64(0) / 1e-50

which compiles just fine.

This patch changes the convlit1 function so that complex ideals
components (real and imag) are correctly truncated to float{32,64}
when doing an ideal -> complex{64, 128} cast.

Fixes #11674

Change-Id: Ic5f8ee3c8cfe4c3bb0621481792c96511723d151
Reviewed-on: https://go-review.googlesource.com/37891
Run-TryBot: Alberto Donizetti <alb.donizetti@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
2017-04-12 17:29:28 +00:00
Daniel Martí
2923b14a7b cmd/compile/internal/gc: don't panic on continue in switch
Continues outside of a loop are not allowed. Most of these possibilities
were tested in label1.go, but one was missing - a plain continue in a
switch/select but no enclosing loop.

This used to error with a "continue not in loop" in 1.8, but recently
was broken by c03e75e5. In particular, innerloop does not only account
for loops, but also for switches and selects. Swap it by bools that
track whether breaks and continues should be allowed.

While at it, improve the wording of errors for breaks that are not where
they should be. Change "loop" by "loop, switch, or select" since they
can be used in any of those.

And add tests to make sure this isn't broken again. Use a separate func
since I couldn't get the compiler to crash on f() itself, possibly due
to the recursive call on itself.

Fixes #19934.

Change-Id: I8f09c6c2107fd95cac50efc2a8cb03cbc128c35e
Reviewed-on: https://go-review.googlesource.com/40357
Run-TryBot: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Robert Griesemer <gri@golang.org>
2017-04-12 14:27:45 +00:00
Josh Bleecher Snyder
423e7e6037 cmd/compile: skip array bounds errors when type is broken
This avoids false positives
like those found in #19880.

Fixes #19880

Change-Id: I583c16cc3c71e7462a72500db9ea2547c468f8c1
Reviewed-on: https://go-review.googlesource.com/40255
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-04-10 20:57:08 +00:00
Josh Bleecher Snyder
b83a916f71 cmd/compile: make iface == iface const evaluation respect !=
Fixes #19911

Change-Id: Ib2b2505fe31ce00c6ffc021a0fe5df510633b44b
Reviewed-on: https://go-review.googlesource.com/40251
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2017-04-10 20:05:56 +00:00
Todd Neal
0d33dc3105 runtime: improve output of panic(x) where x is numeric
Fixes #19658

Change-Id: I41e46073b75c7674e2ed9d6a90ece367ce92166b
Reviewed-on: https://go-review.googlesource.com/39650
Run-TryBot: Todd Neal <todd@tneal.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2017-04-09 22:40:33 +00:00
Josh Bleecher Snyder
c9446398e8 cmd/compile: allow composite literal structs with _ fields
Given code such as

type T struct {
  _ string
}

func f() {
  var x = T{"space"}
  // ...
}

the compiler rewrote the 'var x' line as

var x T
x._ = "space"

The compiler then rejected the assignment to
a blank field, thus rejecting valid code.

It also failed to catch a number of invalid assignments.
And there were insufficient checks for validity
when emitting static data, leading to ICEs.

To fix, check earlier for explicit blanks field names,
explicitly handle legit blanks in sinit,
and don't try to emit static data for nodes
for which typechecking has failed.

Fixes #19482

Change-Id: I594476171d15e6e8ecc6a1749e3859157fe2c929
Reviewed-on: https://go-review.googlesource.com/38006
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-04-07 22:01:18 +00:00
Ilya Tocar
e4a500ce14 cmd/compile/internal/gc: improve comparison with constant strings
Currently we expand comparison with small constant strings into len check
and a sequence of byte comparisons. Generate 16/32/64-bit comparisons,
instead of bytewise on 386 and amd64. Also increase limits on what is
considered small constant string.
Shaves ~30kb (0.5%) from go executable.

This also updates test/prove.go to keep test case valid.

Change-Id: I99ae8871a1d00c96363c6d03d0b890782fa7e1d9
Reviewed-on: https://go-review.googlesource.com/38776
Run-TryBot: Ilya Tocar <ilya.tocar@intel.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
2017-04-07 15:40:25 +00:00
Russ Cox
92cf05daf3 test: deflake locklinear again
Fixes #19276.

Change-Id: I64f8f80331d09956b6698c0b004ed7f7d70857fc
Reviewed-on: https://go-review.googlesource.com/39591
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
2017-04-05 18:46:31 +00:00
Cherry Zhang
a1cedf0842 cmd/link: canonicalize the "package" of dupok text symbols
Dupok symbols may be defined in multiple packages. Its associated
package is chosen sort of arbitrarily (the first containing package
that the linker loads). Canonicalize its package to the package
with which it will be laid down in text, which is the first package
in dependency order that defines the symbol. So later passes (for
example, trampoline insertion pass) know that the dupok symbol
is laid down along with the package.

Fixes #19764.

Change-Id: I7cbc7474ff3016d5069c8b7be04af934abab8bc3
Reviewed-on: https://go-review.googlesource.com/39150
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Lynn Boger <laboger@linux.vnet.ibm.com>
Reviewed-by: David Chase <drchase@google.com>
2017-04-02 03:25:02 +00:00
Josh Bleecher Snyder
5272a2cdc5 cmd/compile: avoid infinite loops in dead blocks during phi insertion
Now that we no longer generate dead code,
it is possible to follow block predecessors
into infinite loops with no variable definitions,
causing an infinite loop during phi insertion.

To fix that, check explicitly whether the predecessor
is dead in lookupVarOutgoing, and if so, bail.

The loop in lookupVarOutgoing is very hot code,
so I am wary of adding anything to it.
However, a long, CPU-only benchmarking run shows no
performance impact at all.

Fixes #19783

Change-Id: I8ef8d267e0b20a29b5cb0fecd7084f76c6f98e47
Reviewed-on: https://go-review.googlesource.com/38913
Reviewed-by: David Chase <drchase@google.com>
2017-03-30 17:06:08 +00:00
David Chase
24e94766c0 cmd/compile: added special case for reflect header fields to esc
The uintptr-typed Data field in reflect.SliceHeader and
reflect.StringHeader needs special treatment because it is
really a pointer.  Add the special treatment in walk for
bug #19168 to escape analysis.

Includes extra debugging that was helpful.

Fixes #19743.

Change-Id: I6dab5002f0d436c3b2a7cdc0156e4fc48a43d6fe
Reviewed-on: https://go-review.googlesource.com/38738
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2017-03-29 17:39:59 +00:00
David Lazar
83843b1610 cmd/compile: fix names of inlined methods from other packages
Previously, an inlined call to wg.Done() in package main would have the
following incorrect symbol name:

    main.(*sync.WaitGroup).Done

This change modifies methodname to return the correct symbol name:

    sync.(*WaitGroup).Done

This fix was suggested by @mdempsky.

Fixes #19467.

Change-Id: I0117838679ac5353789299c618ff8c326712d94d
Reviewed-on: https://go-review.googlesource.com/37866
Reviewed-by: Austin Clements <austin@google.com>
2017-03-29 17:27:49 +00:00
David Lazar
7bf0adc6ad runtime: include inlined calls in result of CallersFrames
Change-Id: If1a3396175f2afa607d56efd1444181334a9ae3e
Reviewed-on: https://go-review.googlesource.com/37862
Reviewed-by: Austin Clements <austin@google.com>
2017-03-29 17:27:38 +00:00
David Lazar
ee97216a17 runtime: handle inlined calls in runtime.Callers
The `skip` argument passed to runtime.Caller and runtime.Callers should
be interpreted as the number of logical calls to skip (rather than the
number of physical stack frames to skip). This changes runtime.Callers
to skip inlined calls in addition to physical stack frames.

The result value of runtime.Callers is a slice of program counters
([]uintptr) representing physical stack frames. If the `skip` parameter
to runtime.Callers skips part-way into a physical frame, there is no
convenient way to encode that in the resulting slice. To avoid changing
the API in an incompatible way, our solution is to store the number of
skipped logical calls of the first frame in the _second_ uintptr
returned by runtime.Callers. Since this number is a small integer, we
encode it as a valid PC value into a small symbol called:

    runtime.skipPleaseUseCallersFrames

For example, if f() calls g(), g() calls `runtime.Callers(2, pcs)`, and
g() is inlined into f, then the frame for f will be partially skipped,
resulting in the following slice:

    pcs = []uintptr{pc_in_f, runtime.skipPleaseUseCallersFrames+1, ...}

We store the skip PC in pcs[1] instead of pcs[0] so that `pcs[i:]` will
truncate the captured stack trace rather than grow it for all i.

Updates #19348.

Change-Id: I1c56f89ac48c29e6f52a5d085567c6d77d499cf1
Reviewed-on: https://go-review.googlesource.com/37854
Run-TryBot: David Lazar <lazard@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
2017-03-29 17:22:08 +00:00
David Lazar
f3f5b10e06 test: allow flags in run action
Previously, we could not run tests with -l=4 on NaCl since the buildrun
action is not supported on NaCl. This lets us run tests with build flags
on NaCl.

Change-Id: I103370c7b823b4ff46f47df97e802da0dc2bc7c3
Reviewed-on: https://go-review.googlesource.com/38170
Run-TryBot: David Lazar <lazard@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
2017-03-29 17:22:00 +00:00
Ian Lance Taylor
835b17c85f test: add test for gccgo compiler crash
Gccgo crashed compiling a function that returned multiple zero-sized values.

Change-Id: I499112cc310e4a4f649962f4d2bc9fee95dee1b6
Reviewed-on: https://go-review.googlesource.com/38772
Reviewed-by: Than McIntosh <thanm@google.com>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-03-28 20:05:34 +00:00
Ilya Tocar
4b50c81356 test/fixedbugs: add a test for 19201
This was cherry-picked to 1.8 as CL 38587, but on master issue was fixed
by CL 37661. Add still relevant part (test) and close issue, since test passes.

Fixes #19201

Change-Id: I6415792e2c465dc6d9bd6583ba1e54b107bcf5cc
Reviewed-on: https://go-review.googlesource.com/37376
Run-TryBot: Ilya Tocar <ilya.tocar@intel.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
Reviewed-by: Keith Randall <khr@golang.org>
2017-03-28 19:07:23 +00:00
Josh Bleecher Snyder
8dafdb1be1 cmd/compile: add Type.WidthCalculated
Prior to this CL, Type.Width != 0 was the mark
of a Type whose Width had been calculated.
As a result, dowidth always recalculated
the width of struct{}.
This, combined with the prohibition on calculating
the width of a FuncArgsStruct and the use of
struct{} as a function argument,
meant that there were circumstances in which
it was forbidden to call dowidth on a type.
This inhibits refactoring to call dowidth automatically,
rather than explicitly.
Instead add a helper method, Type.WidthCalculated,
and implement as Type.Align > 0.
Type.Width is not a good candidate for tracking
whether the width has been calculated;
0 is a value type width, and Width is subject to
too much magic value game-playing.

For good measure, add a test for #11354.

Change-Id: Ie9a9fb5d924e7a2010c1904ae5e38ed4a38eaeb2
Reviewed-on: https://go-review.googlesource.com/38468
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2017-03-28 18:06:09 +00:00
Emmanuel Odeke
e76d6a456b cmd/compile: add test for non interface type switch
Ensure that we have a test for when the compiler
encounters a type switch on a non-interface value.

Change-Id: Icb222f986894d0190e1241ca65396b4950e7d14f
Reviewed-on: https://go-review.googlesource.com/38661
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-03-25 22:52:54 +00:00
Robert Griesemer
5e954047bc cmd/compile: be slightly more tolerant in case of certain syntax errors
Avoid construction of incorrect syntax trees in presence of errors.

For #19663.

Change-Id: I43025a3cf0fe02cae9a57e8bb9489b5f628c3fd7
Reviewed-on: https://go-review.googlesource.com/38604
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2017-03-24 20:07:15 +00:00
Josh Bleecher Snyder
e00e57d67c cmd/compile: ignore all unreachable values during simple phi insertion
Simple phi insertion already had a heuristic to check
for dead blocks, namely having no predecessors.
When we stopped generating code for dead blocks,
we eliminated some values contained in more subtle
dead blocks, which confused phi insertion.
Compensate by beefing up the reachability check.

Fixes #19678

Change-Id: I0081e4a46f7ce2f69b131a34a0553874a0cb373e
Reviewed-on: https://go-review.googlesource.com/38602
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2017-03-24 18:00:15 +00:00
Josh Bleecher Snyder
ad8c17b703 cmd/compile: don't export dead code in inlineable fuctions
CL 37499 allows inlining more functions by ignoring dead code.
However, that dead code can contain non-exportable constructs.
Teach the exporter not to export dead code.

Fixes #19679 

Change-Id: Idb1d3794053514544b6f1035d29262aa6683e1e7
Reviewed-on: https://go-review.googlesource.com/38601
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
2017-03-24 17:21:05 +00:00
Keith Randall
a69754e30c cmd/compile: unnamed parameters do not escape
Fixes #19687

Change-Id: I2e4769b4ec5812506df4ac5dc6bc6a7c5774ecb0
Reviewed-on: https://go-review.googlesource.com/38600
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
2017-03-24 17:14:00 +00:00
Josh Bleecher Snyder
7202341de9 cmd/compile: only SSA [0]T when T is SSA-able
Almost never happens in practice.
The compiler will generate reasonable code anyway,
since assignments involving [0]T never do any work.

Fixes #19696
Fixes #19671

Change-Id: I350d2e0c5bb326c4789c74a046ab0486b2cee49c
Reviewed-on: https://go-review.googlesource.com/38599
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-03-24 16:53:22 +00:00
Robert Griesemer
b5e1ae46ad cmd/compile: don't crash when reporting some syntax errors
Fixes #19667.

Change-Id: Iaa71e2020af123c1bd3ac25e0b760956688e8bdf
Reviewed-on: https://go-review.googlesource.com/38458
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2017-03-23 04:54:27 +00:00
Jason Travis
19040ac871 test/bench/go1: fix typo in parserdata_test.go comment
Change-Id: Iaca02660bdc8262db2b003a94aca661b5cec5576
Reviewed-on: https://go-review.googlesource.com/38437
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2017-03-22 03:23:16 +00:00
Matthew Dempsky
051cbf3f37 cmd/compile: add regress test for issue 19632
Updates #19632.

Change-Id: I1411dd997c8c6a789d17d0dcc0bfbd2281447b16
Reviewed-on: https://go-review.googlesource.com/38401
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Daniel Martí <mvdan@mvdan.cc>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-03-21 19:52:45 +00:00
Hugues Bruant
5d6b7fcaa1 runtime: add mapdelete_fast*
Add benchmarks for map delete with int32/int64/string key

Benchmark results on darwin/amd64

name                 old time/op  new time/op  delta
MapDelete/Int32/1-8   151ns ± 8%    99ns ± 3%  -34.39%  (p=0.008 n=5+5)
MapDelete/Int32/2-8   128ns ± 2%   111ns ±15%  -13.40%  (p=0.040 n=5+5)
MapDelete/Int32/4-8   128ns ± 5%   114ns ± 2%  -10.82%  (p=0.008 n=5+5)
MapDelete/Int64/1-8   144ns ± 0%   104ns ± 3%  -27.53%  (p=0.016 n=4+5)
MapDelete/Int64/2-8   153ns ± 1%   126ns ± 3%  -17.17%  (p=0.008 n=5+5)
MapDelete/Int64/4-8   178ns ± 3%   136ns ± 2%  -23.60%  (p=0.008 n=5+5)
MapDelete/Str/1-8     187ns ± 3%   171ns ± 3%   -8.54%  (p=0.008 n=5+5)
MapDelete/Str/2-8     221ns ± 3%   206ns ± 4%   -7.18%  (p=0.016 n=5+4)
MapDelete/Str/4-8     256ns ± 5%   232ns ± 2%   -9.36%  (p=0.016 n=4+5)

name                     old time/op    new time/op    delta
BinaryTree17-8              2.78s ± 7%     2.70s ± 1%    ~     (p=0.151 n=5+5)
Fannkuch11-8                3.21s ± 2%     3.19s ± 1%    ~     (p=0.310 n=5+5)
FmtFprintfEmpty-8          49.1ns ± 3%    50.2ns ± 2%    ~     (p=0.095 n=5+5)
FmtFprintfString-8         78.6ns ± 4%    80.2ns ± 5%    ~     (p=0.460 n=5+5)
FmtFprintfInt-8            79.7ns ± 1%    81.0ns ± 3%    ~     (p=0.103 n=5+5)
FmtFprintfIntInt-8          117ns ± 2%     119ns ± 0%    ~     (p=0.079 n=5+4)
FmtFprintfPrefixedInt-8     153ns ± 1%     146ns ± 3%  -4.19%  (p=0.024 n=5+5)
FmtFprintfFloat-8           239ns ± 1%     237ns ± 1%    ~     (p=0.246 n=5+5)
FmtManyArgs-8               506ns ± 2%     509ns ± 2%    ~     (p=0.238 n=5+5)
GobDecode-8                7.06ms ± 4%    6.86ms ± 1%    ~     (p=0.222 n=5+5)
GobEncode-8                6.01ms ± 5%    5.87ms ± 2%    ~     (p=0.222 n=5+5)
Gzip-8                      246ms ± 4%     236ms ± 1%  -4.12%  (p=0.008 n=5+5)
Gunzip-8                   37.7ms ± 4%    37.3ms ± 1%    ~     (p=0.841 n=5+5)
HTTPClientServer-8         64.9µs ± 1%    64.4µs ± 0%  -0.80%  (p=0.032 n=5+4)
JSONEncode-8               16.0ms ± 2%    16.2ms ±11%    ~     (p=0.548 n=5+5)
JSONDecode-8               53.2ms ± 2%    53.1ms ± 4%    ~     (p=1.000 n=5+5)
Mandelbrot200-8            4.33ms ± 2%    4.32ms ± 2%    ~     (p=0.841 n=5+5)
GoParse-8                  3.24ms ± 2%    3.27ms ± 4%    ~     (p=0.690 n=5+5)
RegexpMatchEasy0_32-8      86.2ns ± 1%    85.2ns ± 3%    ~     (p=0.286 n=5+5)
RegexpMatchEasy0_1K-8       198ns ± 2%     199ns ± 1%    ~     (p=0.310 n=5+5)
RegexpMatchEasy1_32-8      82.6ns ± 2%    81.8ns ± 1%    ~     (p=0.294 n=5+5)
RegexpMatchEasy1_1K-8       359ns ± 2%     354ns ± 1%  -1.39%  (p=0.048 n=5+5)
RegexpMatchMedium_32-8      123ns ± 2%     123ns ± 1%    ~     (p=0.905 n=5+5)
RegexpMatchMedium_1K-8     38.2µs ± 2%    38.6µs ± 8%    ~     (p=0.690 n=5+5)
RegexpMatchHard_32-8       1.92µs ± 2%    1.91µs ± 5%    ~     (p=0.460 n=5+5)
RegexpMatchHard_1K-8       57.6µs ± 1%    57.0µs ± 2%    ~     (p=0.310 n=5+5)
Revcomp-8                   483ms ± 7%     441ms ± 1%  -8.79%  (p=0.016 n=5+4)
Template-8                 58.0ms ± 1%    58.2ms ± 7%    ~     (p=0.310 n=5+5)
TimeParse-8                 324ns ± 6%     312ns ± 2%    ~     (p=0.087 n=5+5)
TimeFormat-8                330ns ± 1%     329ns ± 1%    ~     (p=0.968 n=5+5)

name                     old speed      new speed      delta
GobDecode-8               109MB/s ± 4%   112MB/s ± 1%    ~     (p=0.222 n=5+5)
GobEncode-8               128MB/s ± 5%   131MB/s ± 2%    ~     (p=0.222 n=5+5)
Gzip-8                   78.9MB/s ± 4%  82.3MB/s ± 1%  +4.25%  (p=0.008 n=5+5)
Gunzip-8                  514MB/s ± 4%   521MB/s ± 1%    ~     (p=0.841 n=5+5)
JSONEncode-8              121MB/s ± 2%   120MB/s ±10%    ~     (p=0.548 n=5+5)
JSONDecode-8             36.5MB/s ± 2%  36.6MB/s ± 4%    ~     (p=1.000 n=5+5)
GoParse-8                17.9MB/s ± 2%  17.7MB/s ± 4%    ~     (p=0.730 n=5+5)
RegexpMatchEasy0_32-8     371MB/s ± 1%   375MB/s ± 3%    ~     (p=0.310 n=5+5)
RegexpMatchEasy0_1K-8    5.15GB/s ± 1%  5.13GB/s ± 1%    ~     (p=0.548 n=5+5)
RegexpMatchEasy1_32-8     387MB/s ± 2%   391MB/s ± 1%    ~     (p=0.310 n=5+5)
RegexpMatchEasy1_1K-8    2.85GB/s ± 2%  2.89GB/s ± 1%    ~     (p=0.056 n=5+5)
RegexpMatchMedium_32-8   8.07MB/s ± 2%  8.06MB/s ± 1%    ~     (p=0.730 n=5+5)
RegexpMatchMedium_1K-8   26.8MB/s ± 2%  26.6MB/s ± 7%    ~     (p=0.690 n=5+5)
RegexpMatchHard_32-8     16.7MB/s ± 2%  16.7MB/s ± 5%    ~     (p=0.421 n=5+5)
RegexpMatchHard_1K-8     17.8MB/s ± 1%  18.0MB/s ± 2%    ~     (p=0.310 n=5+5)
Revcomp-8                 527MB/s ± 6%   577MB/s ± 1%  +9.44%  (p=0.016 n=5+4)
Template-8               33.5MB/s ± 1%  33.4MB/s ± 7%    ~     (p=0.310 n=5+5)

Updates #19495

Change-Id: Ib9ece1690813d9b4788455db43d30891e2138df5
Reviewed-on: https://go-review.googlesource.com/38172
Reviewed-by: Hugues Bruant <hugues.bruant@gmail.com>
Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-03-21 06:07:24 +00:00
Matthew Dempsky
ee272bbf36 cmd/compile/internal/gc: export interface embedding information
Fixes #16369.

Change-Id: I23f8c36370d0da37ac5b5126d012d22f78782782
Reviewed-on: https://go-review.googlesource.com/38392
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
2017-03-21 02:35:40 +00:00
Matthew Dempsky
07de3465be cmd/compile/internal/gc: handle recursive interfaces better
Previously, we handled recursive interfaces by deferring typechecking
of interface methods, while eagerly expanding interface embeddings.

This CL switches to eagerly evaluating interface methods, and
deferring expanding interface embeddings to dowidth. This allows us to
detect recursive interface embeddings with the same mechanism used for
detecting recursive struct embeddings.

Updates #16369.

Change-Id: If4c0320058047f8a2d9b52b9a79de47eb9887f95
Reviewed-on: https://go-review.googlesource.com/38391
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
2017-03-21 01:56:25 +00:00
Robert Griesemer
422c7fea70 cmd/compile: don't permit declarations in post statement of for loop
Report syntax error that was missed when moving to new parser.

Fixes #19610.

Change-Id: Ie5625f907a84089dc56fcccfd4f24df546042783
Reviewed-on: https://go-review.googlesource.com/38375
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-03-20 20:02:34 +00:00
Robert Griesemer
3c7a812485 cmd/compile: eliminate "assignment count mismatch" - not needed anymore
See https://go-review.googlesource.com/#/c/38313/ for background.
It turns out that only a few tests checked for this.

The new error message is shorter and very clear.

Change-Id: I8ab4ad59fb023c8b54806339adc23aefd7dc7b07
Reviewed-on: https://go-review.googlesource.com/38314
Run-TryBot: Robert Griesemer <gri@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2017-03-17 00:31:35 +00:00
Keith Randall
d5dc490519 cmd/compile: intrinsics for math/bits.TrailingZerosX
Implement math/bits.TrailingZerosX using intrinsics.

Generally reorganize the intrinsic spec a bit.
The instrinsics data structure is now built at init time.
This will make doing the other functions in math/bits easier.

Update sys.CtzX to return int instead of uint{64,32} so it
matches math/bits.TrailingZerosX.

Improve the intrinsics a bit for amd64.  We don't need the CMOV
for <64 bit versions.

Update #18616

Change-Id: Ic1c5339c943f961d830ae56f12674d7b29d4ff39
Reviewed-on: https://go-review.googlesource.com/38155
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
2017-03-16 02:44:16 +00:00
Martin Möhrmann
16200c7333 runtime: make complex division c99 compatible
- changes tests to check that the real and imaginary part of the go complex
  division result is equal to the result gcc produces for c99
- changes complex division code to satisfy new complex division test
- adds float functions isNan, isFinite, isInf, abs and copysign
  in the runtime package

Fixes #14644.

name                   old time/op  new time/op  delta
Complex128DivNormal-4  21.8ns ± 6%  13.9ns ± 6%  -36.37%  (p=0.000 n=20+20)
Complex128DivNisNaN-4  14.1ns ± 1%  15.0ns ± 1%   +5.86%  (p=0.000 n=20+19)
Complex128DivDisNaN-4  12.5ns ± 1%  16.7ns ± 1%  +33.79%  (p=0.000 n=19+20)
Complex128DivNisInf-4  10.1ns ± 1%  13.0ns ± 1%  +28.25%  (p=0.000 n=20+19)
Complex128DivDisInf-4  11.0ns ± 1%  20.9ns ± 1%  +90.69%  (p=0.000 n=16+19)
ComplexAlgMap-4        86.7ns ± 1%  86.8ns ± 2%     ~     (p=0.804 n=20+20)

Change-Id: I261f3b4a81f6cc858bc7ff48f6fd1b39c300abf0
Reviewed-on: https://go-review.googlesource.com/37441
Reviewed-by: Robert Griesemer <gri@golang.org>
2017-03-15 22:45:17 +00:00
Josh Bleecher Snyder
604455a46c cmd/compile: ensure TESTQconst AuxInt is in range
Fixes #19555

Change-Id: I7aa0551a90f6bb630c0ba721f3525a8a9cf793fd
Reviewed-on: https://go-review.googlesource.com/38164
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2017-03-15 21:44:08 +00:00
Philip Hofer
710f4d3e7e cmd/compile/internal/gc: mark generated wrappers as DUPOK
Interface wrapper functions now get compiled eagerly in some cases.
Consequently, they may be present in multiple translation units.
Mark them as DUPOK, just like closures.

Fixes #19548
Fixes #19550

Change-Id: Ibe74adb5a62dbf6447db37fde22dcbb3479969ef
Reviewed-on: https://go-review.googlesource.com/38156
Reviewed-by: David Chase <drchase@google.com>
2017-03-15 00:27:13 +00:00
Cherry Zhang
8a44c8efae cmd/compile: don't spill rematerializeable value when resolving merge edges
Fixes #19515.

Change-Id: I4bcce152cef52d00fbb5ab4daf72a6e742bae27c
Reviewed-on: https://go-review.googlesource.com/38158
Reviewed-by: Keith Randall <khr@golang.org>
2017-03-14 22:55:52 +00:00
philhofer
295307ae78 cmd/compile: de-virtualize interface calls
With this change, code like

    h := sha1.New()
    h.Write(buf)
    sum := h.Sum()

gets compiled into static calls rather than
interface calls, because the compiler is able
to prove that 'h' is really a *sha1.digest.

The InterCall re-write rule hits a few dozen times
during make.bash, and hundreds of times during all.bash.

The most common pattern identified by the compiler
is a constructor like

    func New() Interface { return &impl{...} }

where the constructor gets inlined into the caller,
and the result is used immediately. Examples include
{sha1,md5,crc32,crc64,...}.New, base64.NewEncoder,
base64.NewDecoder, errors.New, net.Pipe, and so on.

Some existing benchmarks that change on darwin/amd64:

Crc64/ISO4KB-8        2.67µs ± 1%    2.66µs ± 0%  -0.36%  (p=0.015 n=10+10)
Crc64/ISO1KB-8         694ns ± 0%     690ns ± 1%  -0.59%  (p=0.001 n=10+10)
Adler32KB-8            473ns ± 1%     471ns ± 0%  -0.39%  (p=0.010 n=10+9)

On architectures like amd64, the reduction in code size
appears to contribute more to benchmark improvements than just
removing the indirect call, since that branch gets predicted
accurately when called in a loop.

Updates #19361

Change-Id: I57d4dc21ef40a05ec0fbd55a9bb0eb74cdc67a3d
Reviewed-on: https://go-review.googlesource.com/38139
Run-TryBot: Philip Hofer <phofer@umich.edu>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
2017-03-14 18:49:23 +00:00
Hugues Bruant
ec091b6af2 runtime: add mapassign_fast*
Add benchmarks for map assignment with int32/int64/string key

Benchmark results on darwin/amd64

name                  old time/op  new time/op  delta
MapAssignInt32_255-8  24.7ns ± 3%  17.4ns ± 2%  -29.75%  (p=0.000 n=10+10)
MapAssignInt32_64k-8  45.5ns ± 4%  37.6ns ± 4%  -17.18%  (p=0.000 n=10+10)
MapAssignInt64_255-8  26.0ns ± 3%  17.9ns ± 4%  -31.03%  (p=0.000 n=10+10)
MapAssignInt64_64k-8  46.9ns ± 5%  38.7ns ± 2%  -17.53%  (p=0.000 n=9+10)
MapAssignStr_255-8    47.8ns ± 3%  24.8ns ± 4%  -48.01%  (p=0.000 n=10+10)
MapAssignStr_64k-8    83.0ns ± 3%  51.9ns ± 3%  -37.45%  (p=0.000 n=10+9)

name                     old time/op    new time/op    delta
BinaryTree17-8              3.11s ±19%     2.78s ± 3%    ~     (p=0.095 n=5+5)
Fannkuch11-8                3.26s ± 1%     3.21s ± 2%    ~     (p=0.056 n=5+5)
FmtFprintfEmpty-8          50.3ns ± 1%    50.8ns ± 2%    ~     (p=0.246 n=5+5)
FmtFprintfString-8         82.7ns ± 4%    80.1ns ± 5%    ~     (p=0.238 n=5+5)
FmtFprintfInt-8            82.6ns ± 2%    81.9ns ± 3%    ~     (p=0.508 n=5+5)
FmtFprintfIntInt-8          124ns ± 4%     121ns ± 3%    ~     (p=0.111 n=5+5)
FmtFprintfPrefixedInt-8     158ns ± 6%     160ns ± 2%    ~     (p=0.341 n=5+5)
FmtFprintfFloat-8           249ns ± 2%     245ns ± 2%    ~     (p=0.095 n=5+5)
FmtManyArgs-8               513ns ± 2%     519ns ± 3%    ~     (p=0.151 n=5+5)
GobDecode-8                7.48ms ±12%    7.11ms ± 2%    ~     (p=0.222 n=5+5)
GobEncode-8                6.25ms ± 1%    6.03ms ± 2%  -3.56%  (p=0.008 n=5+5)
Gzip-8                      252ms ± 4%     252ms ± 4%    ~     (p=1.000 n=5+5)
Gunzip-8                   38.4ms ± 3%    38.6ms ± 2%    ~     (p=0.690 n=5+5)
HTTPClientServer-8         76.9µs ±41%    66.4µs ± 6%    ~     (p=0.310 n=5+5)
JSONEncode-8               16.5ms ± 3%    16.7ms ± 3%    ~     (p=0.421 n=5+5)
JSONDecode-8               54.6ms ± 1%    54.3ms ± 2%    ~     (p=0.548 n=5+5)
Mandelbrot200-8            4.45ms ± 3%    4.47ms ± 1%    ~     (p=0.841 n=5+5)
GoParse-8                  3.43ms ± 1%    3.32ms ± 2%  -3.28%  (p=0.008 n=5+5)
RegexpMatchEasy0_32-8      88.2ns ± 3%    89.4ns ± 2%    ~     (p=0.333 n=5+5)
RegexpMatchEasy0_1K-8       205ns ± 1%     206ns ± 1%    ~     (p=0.905 n=5+5)
RegexpMatchEasy1_32-8      85.1ns ± 1%    85.5ns ± 5%    ~     (p=0.690 n=5+5)
RegexpMatchEasy1_1K-8       365ns ± 1%     371ns ± 9%    ~     (p=1.000 n=5+5)
RegexpMatchMedium_32-8      129ns ± 2%     128ns ± 3%    ~     (p=0.730 n=5+5)
RegexpMatchMedium_1K-8     39.8µs ± 0%    39.7µs ± 4%    ~     (p=0.730 n=4+5)
RegexpMatchHard_32-8       1.99µs ± 3%    2.05µs ±16%    ~     (p=0.794 n=5+5)
RegexpMatchHard_1K-8       59.3µs ± 1%    60.3µs ± 7%    ~     (p=1.000 n=5+5)
Revcomp-8                   1.36s ±63%     0.52s ± 5%    ~     (p=0.095 n=5+5)
Template-8                 62.6ms ±14%    60.5ms ± 5%    ~     (p=0.690 n=5+5)
TimeParse-8                 330ns ± 2%     324ns ± 2%    ~     (p=0.087 n=5+5)
TimeFormat-8                350ns ± 3%     340ns ± 1%  -2.86%  (p=0.008 n=5+5)

name                     old speed      new speed      delta
GobDecode-8               103MB/s ±11%   108MB/s ± 2%    ~     (p=0.222 n=5+5)
GobEncode-8               123MB/s ± 1%   127MB/s ± 2%  +3.71%  (p=0.008 n=5+5)
Gzip-8                   77.1MB/s ± 4%  76.9MB/s ± 3%    ~     (p=1.000 n=5+5)
Gunzip-8                  505MB/s ± 3%   503MB/s ± 2%    ~     (p=0.690 n=5+5)
JSONEncode-8              118MB/s ± 3%   116MB/s ± 3%    ~     (p=0.421 n=5+5)
JSONDecode-8             35.5MB/s ± 1%  35.8MB/s ± 2%    ~     (p=0.397 n=5+5)
GoParse-8                16.9MB/s ± 1%  17.4MB/s ± 2%  +3.45%  (p=0.008 n=5+5)
RegexpMatchEasy0_32-8     363MB/s ± 3%   358MB/s ± 2%    ~     (p=0.421 n=5+5)
RegexpMatchEasy0_1K-8    4.98GB/s ± 1%  4.97GB/s ± 1%    ~     (p=0.548 n=5+5)
RegexpMatchEasy1_32-8     376MB/s ± 1%   375MB/s ± 5%    ~     (p=0.690 n=5+5)
RegexpMatchEasy1_1K-8    2.80GB/s ± 1%  2.76GB/s ± 9%    ~     (p=0.841 n=5+5)
RegexpMatchMedium_32-8   7.73MB/s ± 1%  7.76MB/s ± 3%    ~     (p=0.730 n=5+5)
RegexpMatchMedium_1K-8   25.8MB/s ± 0%  25.8MB/s ± 4%    ~     (p=0.651 n=4+5)
RegexpMatchHard_32-8     16.1MB/s ± 3%  15.7MB/s ±14%    ~     (p=0.794 n=5+5)
RegexpMatchHard_1K-8     17.3MB/s ± 1%  17.0MB/s ± 7%    ~     (p=0.984 n=5+5)
Revcomp-8                 273MB/s ±83%   488MB/s ± 5%    ~     (p=0.095 n=5+5)
Template-8               31.1MB/s ±13%  32.1MB/s ± 5%    ~     (p=0.690 n=5+5)

Updates #19495

Change-Id: I116e9a2a4594769318b22d736464de8a98499909
Reviewed-on: https://go-review.googlesource.com/38091
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-03-13 23:43:16 +00:00
David Chase
b59a405656 Revert "cmd/compile: de-virtualize interface calls"
This reverts commit 4e0c7c3f61.

Reason for revert: The presence-of-optimization test program is fragile, breaks under noopt, and might break if the Go libraries are tweaked.  It needs to be (re)written without reference to other packages.

Change-Id: I3aaf1ab006a1a255f961a978e9c984341740e3c7
Reviewed-on: https://go-review.googlesource.com/38097
Reviewed-by: Keith Randall <khr@golang.org>
2017-03-13 21:15:32 +00:00
khr
a51e4cc9ce cmd/compile: zero return parameters earlier
Move the zeroing of results earlier.  In particular, they need to
come before any move-to-heap operations, as those require allocation.
Those allocations are points at which the GC can see the uninitialized
result slots.

For the function:

func f() (x, y, z *int) {
  defer(){}()
  escape(&y)
  return
}

We used to generate code like this:

x = nil
y = nil
&y = new(int)
z = nil

Now we will generate:

x = nil
y = nil
z = nil
&y = new(int)

Since the fix for #18860, the return slots are always live if there
is a defer, so the former ordering allowed the GC to see junk
in the z slot.

Fixes #19078

Change-Id: I71554ae437549725bb79e13b2c100b2911d47ed4
Reviewed-on: https://go-review.googlesource.com/38133
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2017-03-13 19:39:15 +00:00
Philip Hofer
4e0c7c3f61 cmd/compile: de-virtualize interface calls
With this change, code like

    h := sha1.New()
    h.Write(buf)
    sum := h.Sum()

gets compiled into static calls rather than
interface calls, because the compiler is able
to prove that 'h' is really a *sha1.digest.

The InterCall re-write rule hits a few dozen times
during make.bash, and hundreds of times during all.bash.

The most common pattern identified by the compiler
is a constructor like

    func New() Interface { return &impl{...} }

where the constructor gets inlined into the caller,
and the result is used immediately. Examples include
{sha1,md5,crc32,crc64,...}.New, base64.NewEncoder,
base64.NewDecoder, errors.New, net.Pipe, and so on.

Some existing benchmarks that change on darwin/amd64:

Crc64/ISO4KB-8        2.67µs ± 1%    2.66µs ± 0%  -0.36%  (p=0.015 n=10+10)
Crc64/ISO1KB-8         694ns ± 0%     690ns ± 1%  -0.59%  (p=0.001 n=10+10)
Adler32KB-8            473ns ± 1%     471ns ± 0%  -0.39%  (p=0.010 n=10+9)

On architectures like amd64, the reduction in code size
appears to contribute more to benchmark improvements than just
removing the indirect call, since that branch gets predicted
accurately when called in a loop.

Updates #19361

Change-Id: Ia9d30afdd5f6b4d38d38b14b88f308acae8ce7ed
Reviewed-on: https://go-review.googlesource.com/37751
Run-TryBot: Philip Hofer <phofer@umich.edu>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2017-03-13 18:24:57 +00:00
Robert Griesemer
2a5cf48f91 cmd/compile: print columns (not just lines) in error messages
Compiler errors now show the exact line and line byte offset (sometimes
called "column") of where an error occured. For `go tool compile x.go`:

	package p
	const c int = false
	//line foo.go:123
	type t intg

reports

	x.go:2:7: cannot convert false to type int
	foo.go:123[x.go:4:8]: undefined: intg

(Some errors use the "wrong" position for the error message; arguably
the byte offset for the first error should be 15, the position of 'false',
rathen than 7, the position of 'c'. But that is an indepedent issue.)

The byte offset (column) values are measured in bytes; they start at 1,
matching the convention used by editors and IDEs.

Positions modified by //line directives show the line offset only for the
actual source location (in square brackets), not for the "virtual" file and
line number because that code is likely generated and the //line directive
only provides line information.

Because the new format might break existing tools or scripts, printing
of line offsets can be disabled with the new compiler flag -C. We plan
to remove this flag eventually.

Fixes #10324.

Change-Id: I493f5ee6e78457cf7b00025aba6b6e28e50bb740
Reviewed-on: https://go-review.googlesource.com/37970
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2017-03-09 23:29:49 +00:00
David Chase
d71f36b5aa cmd/compile: check loop rescheduling with stack bound, not counter
After benchmarking with a compiler modified to have better
spill location, it became clear that this method of checking
was actually faster on (at least) two different architectures
(ppc64 and amd64) and it also provides more timely interruption
of loops.

This change adds a modified FOR loop node "FORUNTIL" that
checks after executing the loop body instead of before (i.e.,
always at least once).  This ensures that a pointer past the
end of a slice or array is not made visible to the garbage
collector.

Without the rescheduling checks inserted, the restructured
loop from this  change apparently provides a 1% geomean
improvement on PPC64 running the go1 benchmarks; the
improvement on AMD64 is only 0.12%.

Inserting the rescheduling check exposed some peculiar bug
with the ssa test code for s390x; this was updated based on
initial code actually generated for GOARCH=s390x to use
appropriate OpArg, OpAddr, and OpVarDef.

NaCl is disabled in testing.

Change-Id: Ieafaa9a61d2a583ad00968110ef3e7a441abca50
Reviewed-on: https://go-review.googlesource.com/36206
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2017-03-08 18:52:12 +00:00
Matthew Dempsky
c310c688ff cmd/compile, runtime: simplify multiway select implementation
This commit reworks multiway select statements to use normal control
flow primitives instead of the previous setjmp/longjmp-like behavior.
This simplifies liveness analysis and should prevent issues around
"returns twice" function calls within SSA passes.

test/live.go is updated because liveness analysis's CFG is more
representative of actual control flow. The case bodies are the only
real successors of the selectgo call, but previously the selectsend,
selectrecv, etc. calls were included in the successors list too.

Updates #19331.

Change-Id: I7f879b103a4b85e62fc36a270d812f54c0aa3e83
Reviewed-on: https://go-review.googlesource.com/37661
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2017-03-07 20:14:17 +00:00
Alberto Donizetti
e99dafc4a8 cmd/compile: fix misleading "truncated to int" messages
When defining an int const, the compiler tries to cast the RHS
expression to int. The cast may fail for three reasons:

  1. expr is an integer constant that overflows int
  2. expr is a floating point constant
  3. expr is a complex constant, or not a number

In the second case, in order to print a sensible error message, we
must distinguish between a floating point constant that should be
included in the error message and a floating point constant that
cannot be reasonably formatted for inclusion in an error message.

For example, in:

  const a int = 1.1
  const b int = 1 + 1e-100

a is in the former group, while b is in the latter, since the floating
point value resulting from the evaluation of the rhs of the assignment
(1.00...01) is too long to be fully printed in an error message, and
cannot be shortened without making the error message misleading
(rounding or truncating it would result in a "1", which looks like an
integer constant, and it makes little sense in an error message about
an invalid floating point expression).

To fix this problem, we try to format the float value using fconv
(which is used by the error reporting mechanism to format float
arguments), and then parse the resulting string back to a
big.Float. If the result is an integer, we assume that expr is a float
value that cannot be reasonably be formatted as a string, and we emit
an error message that does not include its string representation.

Also, change the error message for overflows to a more conservative
"integer too large", which does not mention overflows that are only
caused by an internal implementation restriction.

Also, change (*Mpint) SetFloat so that it returns a bool (instead of
0/-1 for success/failure).

Fixes #11371

Change-Id: Ibbc73e2ed2eaf41f07827b0649d0eb637150ecaa
Reviewed-on: https://go-review.googlesource.com/35411
Run-TryBot: Alberto Donizetti <alb.donizetti@gmail.com>
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
2017-03-07 19:34:22 +00:00
Robert Griesemer
cf710949a9 Revert "cmd/compile: improve error message if init is directly invoked"
This reverts commit cb6e0639fb.

The fix is incorrect as it's perfectly fine to refer to an
identifier 'init' inside a function, and 'init' may even be
a variable of function value. Misspelling 'init' in that
context would lead to an incorrect error message.

Reopened #8481.

Change-Id: I49787fdf7738213370ae6f0cab54013e9e3394a8
Reviewed-on: https://go-review.googlesource.com/37876
Run-TryBot: Robert Griesemer <gri@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2017-03-06 23:48:37 +00:00
Quentin Smith
4b261a1410 test/fixedbugs: add test for #19403
Change-Id: Ie52dac8eb4daed95e049ad74d5ae101e8a5cb854
Reviewed-on: https://go-review.googlesource.com/37725
Run-TryBot: Quentin Smith <quentin@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2017-03-06 21:39:00 +00:00
Russ Cox
06a6b3a413 test/locklinear: deflake again
On overloaded machines once we get to big N, the machine slowness dominates.
But we only retry once we get to a big N.
Instead, retry for small N too, and die on the first big N that fails.

Change-Id: I3ab9cfb88832ad86e2ba1389a926045091268aeb
Reviewed-on: https://go-review.googlesource.com/37543
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2017-03-06 15:05:42 +00:00
Giovanni Bajo
4fc45ae879 cmd/compile: improve generic rules for BCE based on AND operations.
Match more patterns generated by the compiler where the index for
a bound check is bounded through a AND operation, with different
register sizes.

These rules trigger a dozen of times in a bootstrap.

Change-Id: Ic9fff16f21d08580f19a366c3ee1a372e58357d1
Reviewed-on: https://go-review.googlesource.com/37442
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2017-03-04 16:13:07 +00:00
David Lazar
1c6ef9aeed cmd/compile: copy literals when inlining
Without this, literals keep their original source positions through
inlining, which results in strange jumps in line numbers of inlined
function bodies. By copying literals, inlining can update their source
position like other nodes.

Fixes #15453.

Change-Id: Iad5d9bbfe183883794213266dc30e31bab89ee69
Reviewed-on: https://go-review.googlesource.com/37232
Run-TryBot: David Lazar <lazard@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Russ Cox <rsc@golang.org>
2017-03-03 21:29:32 +00:00
Josh Bleecher Snyder
04fc887761 runtime: delay marking maps as writing until after first alg call
Fixes #19359

Change-Id: I196b47cf0471915b6dc63785e8542aa1876ff695
Reviewed-on: https://go-review.googlesource.com/37665
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2017-03-02 17:38:30 +00:00
Matthew Dempsky
0ee9c46cb1 cmd/compile: add missing WBs for reflect.{Slice,String}Header.Data
Fixes #19168.

Change-Id: I3f4fcc0b189c53819ac29ef8de86fdad76a17488
Reviewed-on: https://go-review.googlesource.com/37663
Reviewed-by: Keith Randall <khr@golang.org>
2017-03-02 17:21:50 +00:00
Josh Bleecher Snyder
542a60fbde cmd/compile: don't crash when slicing non-slice
Fixes #19323

Change-Id: I92d1bdefb15de6178a577a4fa0f0dc004f791904
Reviewed-on: https://go-review.googlesource.com/37584
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2017-03-02 15:48:19 +00:00
Matthew Dempsky
b6c600fc9a cmd/compile/internal/gc: separate builtin and real runtime packages
The builtin runtime package definitions intentionally diverge from the
actual runtime package's, but this only works as long as they never
overlap.

To make it easier to expand the builtin runtime package, this CL now
loads their definitions into a logically separate "go.runtime"
package.  By resetting the package's Prefix field to "runtime", any
references to builtin definitions will still resolve against the real
package runtime.

Fixes #14482.

Passes toolstash -cmp.

Change-Id: I539c0994deaed4506a331f38c5b4d6bc8c95433f
Reviewed-on: https://go-review.googlesource.com/37538
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
2017-03-01 01:06:32 +00:00
philhofer
379567aad1 cmd/compile/ssa: more aggressive constant folding
Add rewrite rules that canonicalize the location
of constants in expressions, and fold conststants
that appear in operations that can be trivially
reassociated.

After this change, the compiler constant-folds
expressions like "4 + x - 1" and "4 & x & 1"

Benchmarks affected on darwin/amd64:

name                     old time/op    new time/op    delta
FmtFprintfInt-8            82.1ns ± 1%    81.7ns ± 1%  -0.46%  (p=0.023 n=8+9)
FmtFprintfIntInt-8          122ns ± 2%     120ns ± 2%  -1.48%  (p=0.047 n=10+10)
FmtManyArgs-8               493ns ± 0%     486ns ± 1%  -1.37%  (p=0.000 n=8+10)
Gzip-8                      230ms ± 0%     229ms ± 1%  -0.46%  (p=0.001 n=10+9)
HTTPClientServer-8         74.5µs ± 1%    73.7µs ± 1%  -1.11%  (p=0.000 n=10+10)
JSONDecode-8               51.7ms ± 0%    51.9ms ± 1%  +0.42%  (p=0.017 n=10+9)
RegexpMatchEasy0_32-8      82.6ns ± 1%    81.7ns ± 0%  -1.02%  (p=0.000 n=9+8)
RegexpMatchMedium_32-8      121ns ± 1%     120ns ± 1%  -1.48%  (p=0.001 n=10+10)
Revcomp-8                   426ms ± 1%     400ms ± 1%  -6.16%  (p=0.000 n=10+10)
TimeFormat-8                330ns ± 1%     327ns ± 0%  -0.82%  (p=0.000 n=10+10)

name                     old speed      new speed      delta
Gzip-8                   84.4MB/s ± 0%  84.8MB/s ± 1%  +0.47%  (p=0.001 n=10+9)
JSONDecode-8             37.6MB/s ± 0%  37.4MB/s ± 1%  -0.42%  (p=0.016 n=10+9)
RegexpMatchEasy0_32-8     387MB/s ± 1%   392MB/s ± 0%  +1.06%  (p=0.000 n=9+8)
RegexpMatchMedium_32-8   8.21MB/s ± 1%  8.34MB/s ± 1%  +1.58%  (p=0.000 n=10+9)
Revcomp-8                 597MB/s ± 1%   636MB/s ± 1%  +6.57%  (p=0.000 n=10+10)

Change-Id: Ie37ff91605b76a984a8400dfd1e34f50bf61c864
Reviewed-on: https://go-review.googlesource.com/37290
Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-02-28 20:25:33 +00:00
Josh Bleecher Snyder
504bc3ed24 cmd/compile, runtime: specialize convT2x, don't alloc for zero vals
Prior to this CL, all runtime conversions
from a concrete value to an interface went
through one of two runtime calls: convT2E or convT2I.
However, in practice, basic types are very common.
Specializing convT2x for those basic types allows
for a more efficient implementation for those types.
For basic scalars and strings, allocation and copying
can use the same methods as normal code.
For pointer-free types, allocation can occur without
zeroing, and copying can take place without GC calls.
For slices, copying is cheaper and simpler.

This CL adds twelve runtime routines:

convT2E16, convT2I16
convT2E32, convT2I32
convT2E64, convT2I64
convT2Estring, convT2Istring
convT2Eslice, convT2Islice
convT2Enoptr, convT2Inoptr

While compiling make.bash, 93% of all convT2x calls
are now to one of these specialized convT2x call.

Within specialized convT2x routines, it is cheap to check
for a zero value, in a way that it is not in general.
When we detect a zero value there, we return a pointer
to zeroVal, rather than allocating.

name                         old time/op  new time/op  delta
ConvT2Ezero/zero/16-8        17.9ns ± 2%   3.0ns ± 3%  -83.20%  (p=0.000 n=56+56)
ConvT2Ezero/zero/32-8        17.8ns ± 2%   3.0ns ± 3%  -83.15%  (p=0.000 n=59+60)
ConvT2Ezero/zero/64-8        20.1ns ± 1%   3.0ns ± 2%  -84.98%  (p=0.000 n=57+57)
ConvT2Ezero/zero/str-8       32.6ns ± 1%   3.0ns ± 4%  -90.70%  (p=0.000 n=59+60)
ConvT2Ezero/zero/slice-8     36.7ns ± 2%   3.0ns ± 2%  -91.78%  (p=0.000 n=59+59)
ConvT2Ezero/zero/big-8       91.9ns ± 2%  85.9ns ± 2%   -6.52%  (p=0.000 n=57+57)
ConvT2Ezero/nonzero/16-8     17.7ns ± 2%  12.7ns ± 3%  -28.38%  (p=0.000 n=55+60)
ConvT2Ezero/nonzero/32-8     17.8ns ± 1%  12.7ns ± 1%  -28.44%  (p=0.000 n=54+57)
ConvT2Ezero/nonzero/64-8     20.0ns ± 1%  15.0ns ± 1%  -24.90%  (p=0.000 n=56+58)
ConvT2Ezero/nonzero/str-8    32.6ns ± 1%  25.7ns ± 1%  -21.17%  (p=0.000 n=58+55)
ConvT2Ezero/nonzero/slice-8  36.8ns ± 2%  30.4ns ± 1%  -17.32%  (p=0.000 n=60+52)
ConvT2Ezero/nonzero/big-8    92.1ns ± 2%  85.9ns ± 2%   -6.70%  (p=0.000 n=57+59)

Benchmarks on a real program (the compiler):

name       old time/op      new time/op      delta
Template        227ms ± 5%       221ms ± 2%  -2.48%  (p=0.000 n=30+26)
Unicode         102ms ± 5%       100ms ± 3%  -1.30%  (p=0.009 n=30+26)
GoTypes         656ms ± 5%       659ms ± 4%    ~     (p=0.208 n=30+30)
Compiler        2.82s ± 2%       2.82s ± 1%    ~     (p=0.614 n=29+27)
Flate           128ms ± 2%       128ms ± 5%    ~     (p=0.783 n=27+28)
GoParser        158ms ± 3%       158ms ± 3%    ~     (p=0.261 n=28+30)
Reflect         408ms ± 7%       401ms ± 3%    ~     (p=0.075 n=30+30)
Tar             123ms ± 6%       121ms ± 8%    ~     (p=0.287 n=29+30)
XML             220ms ± 2%       220ms ± 4%    ~     (p=0.805 n=29+29)

name       old user-ns/op   new user-ns/op   delta
Template   281user-ms ± 4%  279user-ms ± 3%  -0.87%  (p=0.044 n=28+28)
Unicode    142user-ms ± 4%  141user-ms ± 3%  -1.04%  (p=0.015 n=30+27)
GoTypes    884user-ms ± 3%  886user-ms ± 2%    ~     (p=0.532 n=30+30)
Compiler   3.94user-s ± 3%  3.92user-s ± 1%    ~     (p=0.185 n=30+28)
Flate      165user-ms ± 2%  165user-ms ± 4%    ~     (p=0.780 n=27+29)
GoParser   209user-ms ± 2%  208user-ms ± 3%    ~     (p=0.453 n=28+30)
Reflect    533user-ms ± 6%  526user-ms ± 3%    ~     (p=0.057 n=30+30)
Tar        156user-ms ± 6%  154user-ms ± 6%    ~     (p=0.133 n=29+30)
XML        288user-ms ± 4%  288user-ms ± 4%    ~     (p=0.633 n=30+30)

name       old alloc/op     new alloc/op     delta
Template       41.0MB ± 0%      40.9MB ± 0%  -0.11%  (p=0.000 n=29+29)
Unicode        32.6MB ± 0%      32.6MB ± 0%    ~     (p=0.572 n=29+30)
GoTypes         122MB ± 0%       122MB ± 0%  -0.10%  (p=0.000 n=30+30)
Compiler        482MB ± 0%       481MB ± 0%  -0.07%  (p=0.000 n=30+29)
Flate          26.6MB ± 0%      26.6MB ± 0%    ~     (p=0.096 n=30+30)
GoParser       32.7MB ± 0%      32.6MB ± 0%  -0.06%  (p=0.011 n=28+28)
Reflect        84.2MB ± 0%      84.1MB ± 0%  -0.17%  (p=0.000 n=29+30)
Tar            27.7MB ± 0%      27.7MB ± 0%  -0.05%  (p=0.032 n=27+28)
XML            44.7MB ± 0%      44.7MB ± 0%    ~     (p=0.131 n=28+30)

name       old allocs/op    new allocs/op    delta
Template         373k ± 1%        370k ± 1%  -0.76%  (p=0.000 n=30+30)
Unicode          325k ± 1%        325k ± 1%    ~     (p=0.383 n=29+30)
GoTypes         1.16M ± 0%       1.15M ± 0%  -0.75%  (p=0.000 n=29+30)
Compiler        4.15M ± 0%       4.13M ± 0%  -0.59%  (p=0.000 n=30+29)
Flate            238k ± 1%        237k ± 1%  -0.62%  (p=0.000 n=30+30)
GoParser         304k ± 1%        302k ± 1%  -0.64%  (p=0.000 n=30+28)
Reflect         1.00M ± 0%       0.99M ± 0%  -1.10%  (p=0.000 n=29+30)
Tar              245k ± 1%        244k ± 1%  -0.59%  (p=0.000 n=27+29)
XML              391k ± 1%        389k ± 1%  -0.59%  (p=0.000 n=29+30)

Change-Id: Id7f456d690567c2b0a96b0d6d64de8784b6e305f
Reviewed-on: https://go-review.googlesource.com/36476
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2017-02-28 19:23:33 +00:00
Martin Möhrmann
a8f07310e3 cmd/compile: fix assignment order in string range loop
Fixes #18376.

Change-Id: I4fe24f479311cd4cd1bdad9a966b681e50e3d500
Reviewed-on: https://go-review.googlesource.com/35955
Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: Martin Möhrmann <moehrmann@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-02-28 08:23:52 +00:00
Josh Bleecher Snyder
1e29cd8c2b cmd/compile: ignore some dead code during escape analysis
This is the escape analysis analog of CL 37499.

Fixes #12397
Fixes #16871

The only "moved to heap" decisions eliminated by this
CL in std+cmd are:

cmd/compile/internal/gc/const.go:1514: moved to heap: ac
cmd/compile/internal/gc/const.go:1515: moved to heap: bd
cmd/compile/internal/gc/const.go:1516: moved to heap: bc
cmd/compile/internal/gc/const.go:1517: moved to heap: ad
cmd/compile/internal/gc/const.go:1546: moved to heap: ac
cmd/compile/internal/gc/const.go:1547: moved to heap: bd
cmd/compile/internal/gc/const.go:1548: moved to heap: bc
cmd/compile/internal/gc/const.go:1549: moved to heap: ad
cmd/compile/internal/gc/const.go:1550: moved to heap: cc_plus
cmd/compile/internal/gc/export.go:162: moved to heap: copy
cmd/compile/internal/gc/mpfloat.go:66: moved to heap: b
cmd/compile/internal/gc/mpfloat.go:97: moved to heap: b

Change-Id: I0d420b69c84a41ba9968c394e8957910bab5edea
Reviewed-on: https://go-review.googlesource.com/37508
Reviewed-by: David Chase <drchase@google.com>
2017-02-27 21:31:04 +00:00
David Chase
febafe60d4 cmd/compile: added cheapexpr call to simplify operand of CONVIFACE
New special case for booleans and byte-sized integer types
converted to interfaces needs to ensure that the operand is
not too complex, if it were to appear in a parameter list
for example.

Added test, also increased the recursive node dump depth to
a level that was actually useful for an actual bug.

Fixes #19275.

Change-Id: If36ac3115edf439e886703f32d149ee0a46eb2a5
Reviewed-on: https://go-review.googlesource.com/37470
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
2017-02-25 04:53:23 +00:00
Russ Cox
349b7820eb test: deflake locklinear a little
This should help on the openbsd systems where the test mostly passes.

I don't expect it to help on s390x where the test reliably fails.
But it should give more information when it does fail.

For #19276.

Change-Id: I496c291f2b4b0c747b8dd4315477d87d03010059
Reviewed-on: https://go-review.googlesource.com/37348
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2017-02-24 21:18:21 +00:00
Russ Cox
0b8c983ece runtime/pprof/internal/profile: move internal/pprof/profile here
Nothing needs internal/pprof anymore except the runtime/pprof tests.
Move the package here to prevent new dependencies.

Change-Id: Ia119af91cc2b980e0fa03a15f46f69d7f71d2926
Reviewed-on: https://go-review.googlesource.com/37165
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Michael Matloob <matloob@golang.org>
2017-02-24 20:45:21 +00:00
Josh Bleecher Snyder
d9270ecb3a cmd/compile: evaluate zero-sized values converted to interfaces
CL 35562 substituted zerobase for the pointer for
interfaces containing zero-sized values.
However, it failed to evaluate the zero-sized value
expression for side-effects. Fix that.

The other similar interface value optimizations
are not affected, because they all actually use the
value one way or another.

Fixes #19246

Change-Id: I1168a99561477c63c29751d5cd04cf81b5ea509d
Reviewed-on: https://go-review.googlesource.com/37395
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2017-02-24 19:09:41 +00:00
Robert Griesemer
f8ae30c4a2 cmd/compile/internal/parser: improved a couple of error messages
The new syntax tree introduced with 1.8 represents send statements
(ch <- x) as statements; the old syntax tree represented them as
expressions (and parsed them as such) but complained if they were
used in expression context. As a consequence, some of the errors
that in the past were of the form "ch <- x used as value" now look
like "unexpected <- ..." because a "<-" is not valid according to
Go syntax in those situations. Accept the new error message.

Also: Fine-tune handling of misformed for loop headers.

Also: Minor cleanups/better comments.

Fixes #17590.

Change-Id: Ia541dea1f2f015c1b21f5b3ae44aacdec60a8aba
Reviewed-on: https://go-review.googlesource.com/37386
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2017-02-24 18:54:36 +00:00
David Chase
abdb2c35b6 cmd/compile: repaired loop-finder to handle trickier nesting
The loop-A-encloses-loop-C code did not properly handle the
case where really C was already known to be enclosed by B,
and A was nearest-outer to B, not C.

Fixes #19217.

Change-Id: I755dd768e823cb707abdc5302fed39c11cdb34d4
Reviewed-on: https://go-review.googlesource.com/37340
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2017-02-23 22:28:44 +00:00
David R. Jenni
d55f528826 cmd/compile: silence superfluous assignment error message
Avoid printing a second error message when a field of an undefined
variable is accessed.

Fixes #8440.

Change-Id: I3fe0b11fa3423cec3871cb01b5951efa8ea7451a
Reviewed-on: https://go-review.googlesource.com/36751
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-02-23 21:06:11 +00:00
Emmanuel Odeke
19d2061d50 cmd/compile: suppress callsite signatures if any type is unknown
Fixes #19012.

Fallback to return signatures without detailed types.
These error message will be of the form of issue:
* https://golang.org/issues/4215
* https://golang.org/issues/6750

So:
func f(x int, y uint) {
    return x > y
}

f(10, "a" < 3)

will give errors:
too many errors to return
too many arguments in call to f

instead of:

too many errors to return
  have (<T>)
  want ()
too many arguments in call to f
  have (number, <T>)
  want (number, number)

Change-Id: I680abc7cdd8444400e234caddf3ff49c2d69f53d
Reviewed-on: https://go-review.googlesource.com/36806
Reviewed-by: Robert Griesemer <gri@golang.org>
2017-02-22 17:55:45 +00:00
David Chase
11b283092a cmd/compile: add opcode flag hasSideEffects for do-not-remove
Added a flag to generic and various architectures' atomic
operations that are judged to have observable side effects
and thus cannot be dead-code-eliminated.

Test requires GOMAXPROCS > 1 without preemption in loop.

Fixes #19182.

Change-Id: Id2230031abd2cca0bbb32fd68fc8a58fb912070f
Reviewed-on: https://go-review.googlesource.com/37333
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2017-02-22 15:15:47 +00:00
Cherry Zhang
6464e5dc4b cmd/compile: do not fold offset into load/store for args on ARM64
Args may be not at 8-byte aligned offset to SP. When the stack
frame is large, folding the offset of args may cause large
unaligned offsets that does not fit in a machine instruction on
ARM64. Therefore disable folding offsets for args.

This has small performance impact (see below). A better fix would
be letting the assembler backend fix up the offset by loading it
into a register if it doesn't fit into an instruction. And the
compiler can simply generate large load/stores with offset. Since
in most of the cases the offset is aligned or the stack frame is
small, it can fit in an instruction and no fixup is needed. But
this is too complicated for Go 1.8.

name                     old time/op    new time/op    delta
BinaryTree17-8              8.30s ± 0%     8.31s ± 0%    ~     (p=0.579 n=10+10)
Fannkuch11-8                6.14s ± 0%     6.18s ± 0%  +0.53%  (p=0.000 n=9+10)
FmtFprintfEmpty-8           117ns ± 0%     117ns ± 0%    ~     (all equal)
FmtFprintfString-8          196ns ± 0%     197ns ± 0%  +0.72%  (p=0.000 n=10+10)
FmtFprintfInt-8             204ns ± 0%     205ns ± 0%  +0.49%  (p=0.000 n=9+10)
FmtFprintfIntInt-8          302ns ± 0%     307ns ± 1%  +1.46%  (p=0.000 n=10+10)
FmtFprintfPrefixedInt-8     329ns ± 2%     326ns ± 0%    ~     (p=0.083 n=10+10)
FmtFprintfFloat-8           540ns ± 0%     542ns ± 0%  +0.46%  (p=0.000 n=8+7)
FmtManyArgs-8              1.20µs ± 1%    1.19µs ± 1%  -1.02%  (p=0.000 n=10+10)
GobDecode-8                17.3ms ± 1%    17.8ms ± 0%  +2.75%  (p=0.000 n=10+7)
GobEncode-8                15.3ms ± 1%    15.4ms ± 0%  +0.57%  (p=0.004 n=9+10)
Gzip-8                      789ms ± 0%     803ms ± 0%  +1.78%  (p=0.000 n=9+10)
Gunzip-8                    128ms ± 0%     130ms ± 0%  +1.73%  (p=0.000 n=10+9)
HTTPClientServer-8          202µs ± 6%     201µs ±10%    ~     (p=0.739 n=10+10)
JSONEncode-8               42.0ms ± 0%    42.1ms ± 0%  +0.19%  (p=0.028 n=10+9)
JSONDecode-8                159ms ± 0%     161ms ± 0%  +1.05%  (p=0.000 n=9+10)
Mandelbrot200-8            10.1ms ± 0%    10.1ms ± 0%  -0.07%  (p=0.000 n=10+9)
GoParse-8                  8.46ms ± 1%    8.61ms ± 1%  +1.77%  (p=0.000 n=10+10)
RegexpMatchEasy0_32-8       227ns ± 1%     226ns ± 0%  -0.35%  (p=0.001 n=10+9)
RegexpMatchEasy0_1K-8      1.63µs ± 0%    1.63µs ± 0%  -0.13%  (p=0.000 n=10+9)
RegexpMatchEasy1_32-8       250ns ± 0%     249ns ± 0%  -0.40%  (p=0.001 n=8+9)
RegexpMatchEasy1_1K-8      2.07µs ± 0%    2.08µs ± 0%  +0.05%  (p=0.027 n=9+9)
RegexpMatchMedium_32-8      350ns ± 0%     350ns ± 0%    ~     (p=0.412 n=9+8)
RegexpMatchMedium_1K-8      104µs ± 0%     104µs ± 0%  +0.31%  (p=0.000 n=10+7)
RegexpMatchHard_32-8       5.82µs ± 0%    5.82µs ± 0%    ~     (p=0.937 n=9+9)
RegexpMatchHard_1K-8        176µs ± 0%     176µs ± 0%  +0.03%  (p=0.000 n=9+8)
Revcomp-8                   1.36s ± 1%     1.37s ± 1%    ~     (p=0.218 n=10+10)
Template-8                  151ms ± 1%     156ms ± 1%  +3.21%  (p=0.000 n=10+10)
TimeParse-8                 737ns ± 0%     758ns ± 2%  +2.74%  (p=0.000 n=10+10)
TimeFormat-8                801ns ± 2%     789ns ± 1%  -1.51%  (p=0.000 n=10+10)
[Geo mean]                  142µs          143µs       +0.50%

Fixes #19137.

Change-Id: Ib8a21ea98c0ffb2d282a586535b213cc163e1b67
Reviewed-on: https://go-review.googlesource.com/37251
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
2017-02-21 19:39:08 +00:00
Cherry Zhang
3557d54609 cmd/compile: check both syms when folding address into load/store on ARM64
The rules for folding addresses into load/stores checks sym1 is
not on stack (because the stack offset is not known at that point).
But sym1 could be nil, which invalidates the check. Check merged
sym instead.

Fixes #19137.

Change-Id: I8574da22ced1216bb5850403d8f08ec60a8d1005
Reviewed-on: https://go-review.googlesource.com/37145
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
2017-02-17 21:23:24 +00:00
Cherry Zhang
98061fa5f3 cmd/compile: re-enable nilcheck removal in same block
Nil check removal in the same block is disabled due to issue 18725:
because the values are not ordered, a nilcheck may influence a
value that is logically before it. This CL re-enables same-block
nilcheck removal by ordering values in store order first.

Updates #18725.

Change-Id: I287a38525230c14c5412cbcdbc422547dabd54f6
Reviewed-on: https://go-review.googlesource.com/35496
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
2017-02-17 19:19:59 +00:00
Robert Griesemer
1693e7b6f2 cmd/compile/internal/syntax: better errors and recovery for invalid character literals
Fixes #15611.

Change-Id: I352b145026466cafef8cf87addafbd30716bda24
Reviewed-on: https://go-review.googlesource.com/37138
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2017-02-16 21:46:43 +00:00
Russ Cox
990124da2a runtime: use balanced tree for addr lookup in semaphore implementation
CL 36792 fixed #17953, a linear scan caused by n goroutines piling into
two different locks that hashed to the same bucket in the semaphore table.
In that CL, n goroutines contending for 2 unfortunately chosen locks
went from O(n²) to O(n).

This CL fixes a different linear scan, when n goroutines are contending for
n/2 different locks that all hash to the same bucket in the semaphore table.
In this CL, n goroutines contending for n/2 unfortunately chosen locks
goes from O(n²) to O(n log n). This case is much less likely, but any linear
scan eventually hurts, so we might as well fix it while the problem is fresh
in our minds.

The new test in this CL checks for both linear scans.

The effect of this CL on the sync benchmarks is negligible
(but it fixes the new test).

name                      old time/op    new time/op    delta
Cond1-48                     576ns ±10%     575ns ±13%     ~     (p=0.679 n=71+71)
Cond2-48                    1.59µs ± 8%    1.61µs ± 9%     ~     (p=0.107 n=73+69)
Cond4-48                    4.56µs ± 7%    4.55µs ± 7%     ~     (p=0.670 n=74+72)
Cond8-48                    9.87µs ± 9%    9.90µs ± 7%     ~     (p=0.507 n=69+73)
Cond16-48                   20.4µs ± 7%    20.4µs ±10%     ~     (p=0.588 n=69+71)
Cond32-48                   45.4µs ±10%    45.4µs ±14%     ~     (p=0.944 n=73+73)
UncontendedSemaphore-48     19.7ns ±12%    19.7ns ± 8%     ~     (p=0.589 n=65+63)
ContendedSemaphore-48       55.4ns ±26%    54.9ns ±32%     ~     (p=0.441 n=75+75)
MutexUncontended-48         0.63ns ± 0%    0.63ns ± 0%     ~     (all equal)
Mutex-48                     210ns ± 6%     213ns ±10%   +1.30%  (p=0.035 n=70+74)
MutexSlack-48                210ns ± 7%     211ns ± 9%     ~     (p=0.184 n=71+72)
MutexWork-48                 299ns ± 5%     300ns ± 5%     ~     (p=0.678 n=73+75)
MutexWorkSlack-48            302ns ± 6%     300ns ± 5%     ~     (p=0.149 n=74+72)
MutexNoSpin-48               135ns ± 6%     135ns ±10%     ~     (p=0.788 n=67+75)
MutexSpin-48                 693ns ± 5%     689ns ± 6%     ~     (p=0.092 n=65+74)
Once-48                     0.22ns ±25%    0.22ns ±24%     ~     (p=0.882 n=74+73)
Pool-48                     5.88ns ±36%    5.79ns ±24%     ~     (p=0.655 n=69+69)
PoolOverflow-48             4.79µs ±18%    4.87µs ±20%     ~     (p=0.233 n=75+75)
SemaUncontended-48          0.80ns ± 1%    0.82ns ± 8%   +2.46%  (p=0.000 n=60+74)
SemaSyntNonblock-48          103ns ± 4%     102ns ± 5%   -1.11%  (p=0.003 n=75+75)
SemaSyntBlock-48             104ns ± 4%     104ns ± 5%     ~     (p=0.231 n=71+75)
SemaWorkNonblock-48          128ns ± 4%     129ns ± 6%   +1.51%  (p=0.000 n=63+75)
SemaWorkBlock-48             129ns ± 8%     130ns ± 7%     ~     (p=0.072 n=75+74)
RWMutexUncontended-48       2.35ns ± 1%    2.35ns ± 0%     ~     (p=0.144 n=70+55)
RWMutexWrite100-48           139ns ±18%     141ns ±21%     ~     (p=0.071 n=75+73)
RWMutexWrite10-48            145ns ± 9%     145ns ± 8%     ~     (p=0.553 n=75+75)
RWMutexWorkWrite100-48       297ns ±13%     297ns ±15%     ~     (p=0.519 n=75+74)
RWMutexWorkWrite10-48        588ns ± 7%     585ns ± 5%     ~     (p=0.173 n=73+70)
WaitGroupUncontended-48     0.87ns ± 0%    0.87ns ± 0%     ~     (all equal)
WaitGroupAddDone-48         63.2ns ± 4%    62.7ns ± 4%   -0.82%  (p=0.027 n=72+75)
WaitGroupAddDoneWork-48      109ns ± 5%     109ns ± 4%     ~     (p=0.233 n=75+75)
WaitGroupWait-48            0.17ns ± 0%    0.16ns ±16%   -8.55%  (p=0.000 n=56+75)
WaitGroupWaitWork-48        1.78ns ± 1%    2.08ns ± 5%  +16.92%  (p=0.000 n=74+70)
WaitGroupActuallyWait-48    52.0ns ± 3%    50.6ns ± 5%   -2.70%  (p=0.000 n=71+69)

https://perf.golang.org/search?q=upload:20170215.1

Change-Id: Ia29a8bd006c089e401ec4297c3038cca656bcd0a
Reviewed-on: https://go-review.googlesource.com/37103
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-02-16 17:52:15 +00:00
Robert Griesemer
d390283ff4 cmd/compile/internal/syntax: compiler directives must start at beginning of line
- ignore them, if they don't.
- added tests

Fixes #18393.

Change-Id: I13f87b81ac6b9138ab5031bb3dd6bebc4c548156
Reviewed-on: https://go-review.googlesource.com/37020
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2017-02-15 06:49:21 +00:00
Robert Griesemer
2770c507a5 cmd/compile: fix position for "missing type in composite literal" error
Fixes #18231.

Change-Id: If1615da4db0e6f0516369a1dc37340d80c78f237
Reviewed-on: https://go-review.googlesource.com/37018
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2017-02-15 01:33:44 +00:00
Robert Griesemer
5267ac2732 cmd/compile/internal/syntax: establish principled position information
Until now, the parser set the position for each Node to the position of
the first token belonging to that node. For compatibility with the now
defunct gc parser, in many places that position information was modified
when the gcCompat flag was set (which it was, by default). Furthermore,
in some places, position information was not set at all.

This change removes the gcCompat flag and all associated code, and sets
position information for all nodes in a more principled way, as proposed
by mdempsky (see #16943 for details). Specifically, the position of a
node may not be at the very beginning of the respective production. For
instance for an Operation `a + b`, the position associated with the node
is the position of the `+`. Thus, for `a + b + c` we now get different
positions for the two additions.

This change does not pass toolstash -cmp because position information
recorded in export data and pcline tables is different. There are no
other functional changes.

Added test suite testing the position of all nodes.

Fixes #16943.

Change-Id: I3fc02bf096bc3b3d7d2fa655dfd4714a1a0eb90c
Reviewed-on: https://go-review.googlesource.com/37017
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2017-02-15 01:33:03 +00:00
Cherry Zhang
78200799a2 cmd/compile: undo special handling of zero-valued STRUCTLIT
CL 35261 introduces special handling of zero-valued STRUCTLIT for
efficient struct zeroing. But it didn't cover all use cases, for
example, CONVNOP STRUCTLIT is not handled.

On the other hand, CL 34566 handles zeroing earlier, so we don't
need the change in CL 35261 for efficient zeroing. Other uses of
zero-valued struct literals are very rare. So undo the change in
walk.go in CL 35261.

Add a test for efficient zeroing.

Fixes #19084.

Change-Id: I0807f7423fb44d47bf325b3c1ce9611a14953853
Reviewed-on: https://go-review.googlesource.com/36955
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Keith Randall <khr@golang.org>
2017-02-14 18:57:56 +00:00
Robert Griesemer
efb3cab960 cmd/compile/internal/syntax: generalize error about var decls in init clauses
Change-Id: I62f9748b97bec245338ebf9686fbf6ad6dc6a9c2
Reviewed-on: https://go-review.googlesource.com/36931
Run-TryBot: Robert Griesemer <gri@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2017-02-13 23:15:32 +00:00
Robert Griesemer
f823d30514 cmd/compile/internal/syntax: better error for malformed 'if' statements
Use distinction between explicit and automatically inserted semicolons
to provide a better error message if the condition in an 'if' statement
is missing.

For #18747.

Change-Id: Iac167ae4e5ad53d2dc73f746b4dee9912434bb59
Reviewed-on: https://go-review.googlesource.com/36930
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2017-02-13 22:02:36 +00:00
Robert Griesemer
ee2f5fafd8 cmd/compile/internal/parser: don't crash after unexpected token
Added missing nil-check. We will get rid of the gcCompat corrections
shortly but it's still worthwhile having the new test case added.

Fixes #19056.

Change-Id: I35bd938a4d789058da15724e34c05e5e631ecad0
Reviewed-on: https://go-review.googlesource.com/36908
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2017-02-13 18:03:43 +00:00
Josh Bleecher Snyder
2c91bb4c8a cmd/compile: make panicwrap argument-free
When code defines a method on T,
the compiler generates a corresponding wrapper method on *T.
The first thing the wrapper does is check whether
the pointer is nil and if so, call panicwrap.
This is done to provide a useful error message.

The existing implementation gets its information
from arguments set up by the compiler.
However, with some trouble, this information can
be extracted from the name of the wrapper method itself.

Removing the arguments to panicwrap simplifies and
shrinks the wrapper method.
It also means that the call to panicwrap does not
require any stack space.
This enables a further optimization on amd64/x86,
which is to skip the function prologue if nothing
else in the method requires stack space.
This is frequently the case in simple, hot methods,
such as Less and Swap in sort.Interface implementations.

Fixes #19040.

Benchmarks for package sort on amd64:

name                  old time/op  new time/op  delta
SearchWrappers-8       104ns ± 1%   104ns ± 1%    ~     (p=0.286 n=27+27)
SortString1K-8         128µs ± 1%   128µs ± 1%  -0.44%  (p=0.004 n=30+30)
SortString1K_Slice-8   118µs ± 2%   117µs ± 1%    ~     (p=0.106 n=30+30)
StableString1K-8      18.6µs ± 1%  18.6µs ± 1%    ~     (p=0.446 n=28+26)
SortInt1K-8           65.9µs ± 1%  60.7µs ± 1%  -7.96%  (p=0.000 n=28+30)
StableInt1K-8         75.3µs ± 2%  72.8µs ± 1%  -3.41%  (p=0.000 n=30+30)
StableInt1K_Slice-8   57.7µs ± 1%  57.7µs ± 1%    ~     (p=0.515 n=30+30)
SortInt64K-8          6.28ms ± 1%  6.01ms ± 1%  -4.19%  (p=0.000 n=28+28)
SortInt64K_Slice-8    5.04ms ± 1%  5.04ms ± 1%    ~     (p=0.927 n=28+27)
StableInt64K-8        6.65ms ± 1%  6.38ms ± 1%  -3.97%  (p=0.000 n=26+30)
Sort1e2-8             37.9µs ± 1%  37.2µs ± 1%  -1.89%  (p=0.000 n=29+27)
Stable1e2-8           77.0µs ± 1%  74.7µs ± 1%  -3.06%  (p=0.000 n=27+30)
Sort1e4-8             8.21ms ± 2%  7.98ms ± 1%  -2.77%  (p=0.000 n=29+30)
Stable1e4-8           24.8ms ± 1%  24.3ms ± 1%  -2.31%  (p=0.000 n=28+30)
Sort1e6-8              1.27s ± 4%   1.22s ± 1%  -3.42%  (p=0.000 n=30+29)
Stable1e6-8            5.06s ± 1%   4.92s ± 1%  -2.77%  (p=0.000 n=25+29)
[Geo mean]             731µs        714µs       -2.29%

Before/after assembly for sort.(*intPairs).Less follows.
It can be optimized further, but that's for a follow-up CL.

Before:

"".(*intPairs).Less t=1 size=214 args=0x20 locals=0x38
	0x0000 00000 (<autogenerated>:1)	TEXT	"".(*intPairs).Less(SB), $56-32
	0x0000 00000 (<autogenerated>:1)	MOVQ	(TLS), CX
	0x0009 00009 (<autogenerated>:1)	CMPQ	SP, 16(CX)
	0x000d 00013 (<autogenerated>:1)	JLS	204
	0x0013 00019 (<autogenerated>:1)	SUBQ	$56, SP
	0x0017 00023 (<autogenerated>:1)	MOVQ	BP, 48(SP)
	0x001c 00028 (<autogenerated>:1)	LEAQ	48(SP), BP
	0x0021 00033 (<autogenerated>:1)	MOVQ	32(CX), BX
	0x0025 00037 (<autogenerated>:1)	TESTQ	BX, BX
	0x0028 00040 (<autogenerated>:1)	JEQ	55
	0x002a 00042 (<autogenerated>:1)	LEAQ	64(SP), DI
	0x002f 00047 (<autogenerated>:1)	CMPQ	(BX), DI
	0x0032 00050 (<autogenerated>:1)	JNE	55
	0x0034 00052 (<autogenerated>:1)	MOVQ	SP, (BX)
	0x0037 00055 (<autogenerated>:1)	NOP
	0x0037 00055 (<autogenerated>:1)	FUNCDATA	$0, gclocals·4032f753396f2012ad1784f398b170f4(SB)
	0x0037 00055 (<autogenerated>:1)	FUNCDATA	$1, gclocals·69c1753bd5f81501d95132d08af04464(SB)
	0x0037 00055 (<autogenerated>:1)	MOVQ	""..this+64(FP), AX
	0x003c 00060 (<autogenerated>:1)	TESTQ	AX, AX
	0x003f 00063 (<autogenerated>:1)	JEQ	$0, 135
	0x0041 00065 (<autogenerated>:1)	MOVQ	(AX), CX
	0x0044 00068 (<autogenerated>:1)	MOVQ	8(AX), AX
	0x0048 00072 (<autogenerated>:1)	MOVQ	"".i+72(FP), DX
	0x004d 00077 (<autogenerated>:1)	CMPQ	DX, AX
	0x0050 00080 (<autogenerated>:1)	JCC	$0, 128
	0x0052 00082 (<autogenerated>:1)	SHLQ	$4, DX
	0x0056 00086 (<autogenerated>:1)	MOVQ	(CX)(DX*1), DX
	0x005a 00090 (<autogenerated>:1)	MOVQ	"".j+80(FP), BX
	0x005f 00095 (<autogenerated>:1)	CMPQ	BX, AX
	0x0062 00098 (<autogenerated>:1)	JCC	$0, 128
	0x0064 00100 (<autogenerated>:1)	SHLQ	$4, BX
	0x0068 00104 (<autogenerated>:1)	MOVQ	(CX)(BX*1), AX
	0x006c 00108 (<autogenerated>:1)	CMPQ	DX, AX
	0x006f 00111 (<autogenerated>:1)	SETLT	AL
	0x0072 00114 (<autogenerated>:1)	MOVB	AL, "".~r2+88(FP)
	0x0076 00118 (<autogenerated>:1)	MOVQ	48(SP), BP
	0x007b 00123 (<autogenerated>:1)	ADDQ	$56, SP
	0x007f 00127 (<autogenerated>:1)	RET
	0x0080 00128 (<autogenerated>:1)	PCDATA	$0, $1
	0x0080 00128 (<autogenerated>:1)	CALL	runtime.panicindex(SB)
	0x0085 00133 (<autogenerated>:1)	UNDEF
	0x0087 00135 (<autogenerated>:1)	LEAQ	go.string."sort_test"(SB), AX
	0x008e 00142 (<autogenerated>:1)	MOVQ	AX, (SP)
	0x0092 00146 (<autogenerated>:1)	MOVQ	$9, 8(SP)
	0x009b 00155 (<autogenerated>:1)	LEAQ	go.string."intPairs"(SB), AX
	0x00a2 00162 (<autogenerated>:1)	MOVQ	AX, 16(SP)
	0x00a7 00167 (<autogenerated>:1)	MOVQ	$8, 24(SP)
	0x00b0 00176 (<autogenerated>:1)	LEAQ	go.string."Less"(SB), AX
	0x00b7 00183 (<autogenerated>:1)	MOVQ	AX, 32(SP)
	0x00bc 00188 (<autogenerated>:1)	MOVQ	$4, 40(SP)
	0x00c5 00197 (<autogenerated>:1)	PCDATA	$0, $1
	0x00c5 00197 (<autogenerated>:1)	CALL	runtime.panicwrap(SB)
	0x00ca 00202 (<autogenerated>:1)	UNDEF
	0x00cc 00204 (<autogenerated>:1)	NOP
	0x00cc 00204 (<autogenerated>:1)	PCDATA	$0, $-1
	0x00cc 00204 (<autogenerated>:1)	CALL	runtime.morestack_noctxt(SB)
	0x00d1 00209 (<autogenerated>:1)	JMP	0

After:

"".(*intPairs).Swap t=1 size=147 args=0x18 locals=0x8
	0x0000 00000 (<autogenerated>:1)	TEXT	"".(*intPairs).Swap(SB), $8-24
	0x0000 00000 (<autogenerated>:1)	MOVQ	(TLS), CX
	0x0009 00009 (<autogenerated>:1)	SUBQ	$8, SP
	0x000d 00013 (<autogenerated>:1)	MOVQ	BP, (SP)
	0x0011 00017 (<autogenerated>:1)	LEAQ	(SP), BP
	0x0015 00021 (<autogenerated>:1)	MOVQ	32(CX), BX
	0x0019 00025 (<autogenerated>:1)	TESTQ	BX, BX
	0x001c 00028 (<autogenerated>:1)	JEQ	43
	0x001e 00030 (<autogenerated>:1)	LEAQ	16(SP), DI
	0x0023 00035 (<autogenerated>:1)	CMPQ	(BX), DI
	0x0026 00038 (<autogenerated>:1)	JNE	43
	0x0028 00040 (<autogenerated>:1)	MOVQ	SP, (BX)
	0x002b 00043 (<autogenerated>:1)	NOP
	0x002b 00043 (<autogenerated>:1)	FUNCDATA	$0, gclocals·e6397a44f8e1b6e77d0f200b4fba5269(SB)
	0x002b 00043 (<autogenerated>:1)	FUNCDATA	$1, gclocals·69c1753bd5f81501d95132d08af04464(SB)
	0x002b 00043 (<autogenerated>:1)	MOVQ	""..this+16(FP), AX
	0x0030 00048 (<autogenerated>:1)	TESTQ	AX, AX
	0x0033 00051 (<autogenerated>:1)	JEQ	$0, 140
	0x0035 00053 (<autogenerated>:1)	MOVQ	(AX), CX
	0x0038 00056 (<autogenerated>:1)	MOVQ	8(AX), AX
	0x003c 00060 (<autogenerated>:1)	MOVQ	"".i+24(FP), DX
	0x0041 00065 (<autogenerated>:1)	CMPQ	DX, AX
	0x0044 00068 (<autogenerated>:1)	JCC	$0, 133
	0x0046 00070 (<autogenerated>:1)	SHLQ	$4, DX
	0x004a 00074 (<autogenerated>:1)	MOVQ	8(CX)(DX*1), BX
	0x004f 00079 (<autogenerated>:1)	MOVQ	(CX)(DX*1), SI
	0x0053 00083 (<autogenerated>:1)	MOVQ	"".j+32(FP), DI
	0x0058 00088 (<autogenerated>:1)	CMPQ	DI, AX
	0x005b 00091 (<autogenerated>:1)	JCC	$0, 133
	0x005d 00093 (<autogenerated>:1)	SHLQ	$4, DI
	0x0061 00097 (<autogenerated>:1)	MOVQ	8(CX)(DI*1), AX
	0x0066 00102 (<autogenerated>:1)	MOVQ	(CX)(DI*1), R8
	0x006a 00106 (<autogenerated>:1)	MOVQ	R8, (CX)(DX*1)
	0x006e 00110 (<autogenerated>:1)	MOVQ	AX, 8(CX)(DX*1)
	0x0073 00115 (<autogenerated>:1)	MOVQ	SI, (CX)(DI*1)
	0x0077 00119 (<autogenerated>:1)	MOVQ	BX, 8(CX)(DI*1)
	0x007c 00124 (<autogenerated>:1)	MOVQ	(SP), BP
	0x0080 00128 (<autogenerated>:1)	ADDQ	$8, SP
	0x0084 00132 (<autogenerated>:1)	RET
	0x0085 00133 (<autogenerated>:1)	PCDATA	$0, $1
	0x0085 00133 (<autogenerated>:1)	CALL	runtime.panicindex(SB)
	0x008a 00138 (<autogenerated>:1)	UNDEF
	0x008c 00140 (<autogenerated>:1)	PCDATA	$0, $1
	0x008c 00140 (<autogenerated>:1)	CALL	runtime.panicwrap(SB)
	0x0091 00145 (<autogenerated>:1)	UNDEF

Change-Id: I15bb8435f0690badb868799f313ed8817335efd3
Reviewed-on: https://go-review.googlesource.com/36809
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2017-02-11 23:27:35 +00:00
Dhananjay Nakrani
1cde87b312 cmd/compile: Ensure left-to-right assignment
Add temporaries to reorder the assignment for OAS2XXX nodes.
This makes orderstmt(), rewrite
  a, b, c = ...
as
  tmp1, tmp2, tmp3 = ...
  a, b, c = tmp1, tmp2, tmp3
and
  a, ok = ...
as
  t1, t2 = ...
  a  = t1
  ok = t2

Fixes #13433.

Change-Id: Id0f5956e3a254d0a6f4b89b5f7b0e055b1f0e21f
Reviewed-on: https://go-review.googlesource.com/34713
Run-TryBot: Dhananjay Nakrani <dhananjayn@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2017-02-11 21:46:21 +00:00
Robert Griesemer
3fd3171c2c cmd/compile/internal/syntax: removed gcCompat code needed to pass orig. tests
The gcCompat mode was introduced to match the new parser's node position
setup exactly with the positions used by the original parser. Some of the
gcCompat adjustments were required to satisfy syntax error test cases,
and the rest were required to make toolstash cmp pass.

This change removes the former gcCompat adjustments and instead adjusts
the respective test cases as necessary. In some cases this makes the error
lines consistent with the ones reported by gccgo.

Where it has changed, the position associated with a given syntactic construct
is the position (line/col number) of the left-most token belonging to the
construct.

Change-Id: I5b60c00c5999a895c4d6d6e9b383c6405ccf725c
Reviewed-on: https://go-review.googlesource.com/36695
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2017-02-10 01:22:30 +00:00
Robert Griesemer
3c22e5ca27 cmd/compile/internal/parser: improved syntax error for incorrect if/for/switch header
Starting the error message with "expecting" rather than "missing"
causes the syntax error mechanism to add additional helpful info
(it recognizes "expecting" but not "missing").

Fixes #17328.

Change-Id: I8482ca5e5a6a6b22e0ed0d831b7328e264156334
Reviewed-on: https://go-review.googlesource.com/36637
Run-TryBot: Robert Griesemer <gri@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-02-09 03:54:47 +00:00
Robert Griesemer
9799622f09 cmd/compile/internal/syntax: differentiate between ';' and '\n' in syntax errors
Towards better syntax error messages: With this change, the parser knows whether
a semicolon was an actual ';' in the source, or whether it was an automatically
inserted semicolon as result of a '\n' or EOF. Using this information in error
messages makes them more understandable.

For #17328.

Change-Id: I8cd9accee8681b62569d0ecef922d38682b401eb
Reviewed-on: https://go-review.googlesource.com/36636
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2017-02-09 01:45:17 +00:00
Cherry Zhang
a146dd3a2f cmd/compile: handle DOT STRUCTLIT for zero-valued struct in SSA
CL 35261 makes SSA handle zero-valued STRUCTLIT, but DOT operation
was not handled.

Fixes #18994.

Change-Id: Ic7976036acca1523b0b14afac4d170797e8aee20
Reviewed-on: https://go-review.googlesource.com/36565
Run-TryBot: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-02-08 21:01:51 +00:00
David Lazar
e3efdffacd cmd/compile: include linknames in export data
This lets the compiler inline functions that contain a linknamed symbol.
Previously, the net/http tests would fail to build with -l=4 because
the compiler inlined functions that call net.byteIndex (which is
linknamed to strings.IndexByte).

This changes only the compiler-specific export data, so we don't need to
bump the export format version number.

The following benchmark results show how the size of package export data
is impacted by this change. These benchmarks were created by compiling
the go1 benchmark and running `go tool pack x` to extract the export
data from the resulting .a files.

name                                          old bytes   new bytes   delta
bufio                                        3.48k ± 0%  3.58k ± 0%  +2.90%
bytes                                        5.05k ± 0%  5.16k ± 0%  +2.16%
compress/bzip2                               2.61k ± 0%  2.68k ± 0%  +2.68%
compress/flate                               5.07k ± 0%  5.14k ± 0%  +1.40%
compress/gzip                                8.26k ± 0%  8.40k ± 0%  +1.70%
container/list                               1.69k ± 0%  1.76k ± 0%  +4.07%
context                                      3.93k ± 0%  4.01k ± 0%  +1.86%
crypto                                       1.03k ± 0%  1.03k ± 0%  +0.39%
crypto/aes                                     475 ± 0%    475 ± 0%  +0.00%
crypto/cipher                                1.18k ± 0%  1.18k ± 0%  +0.00%
crypto/des                                     502 ± 0%    502 ± 0%  +0.00%
crypto/dsa                                   5.71k ± 0%  5.77k ± 0%  +1.16%
crypto/ecdsa                                 6.67k ± 0%  6.75k ± 0%  +1.08%
crypto/elliptic                              6.28k ± 0%  6.35k ± 0%  +1.07%
crypto/hmac                                    464 ± 0%    464 ± 0%  +0.00%
crypto/internal/cipherhw                       313 ± 0%    313 ± 0%  +0.00%
crypto/md5                                     691 ± 0%    695 ± 0%  +0.58%
crypto/rand                                  5.37k ± 0%  5.43k ± 0%  +1.23%
crypto/rc4                                     512 ± 0%    512 ± 0%  +0.00%
crypto/rsa                                   7.05k ± 0%  7.12k ± 0%  +1.05%
crypto/sha1                                    756 ± 0%    760 ± 0%  +0.53%
crypto/sha256                                  523 ± 0%    523 ± 0%  +0.00%
crypto/sha512                                  662 ± 0%    662 ± 0%  +0.00%
crypto/subtle                                  835 ± 0%    873 ± 0%  +4.55%
crypto/tls                                   28.1k ± 0%  28.5k ± 0%  +1.30%
crypto/x509                                  17.7k ± 0%  17.9k ± 0%  +1.04%
crypto/x509/pkix                             9.75k ± 0%  9.90k ± 0%  +1.50%
encoding                                       473 ± 0%    473 ± 0%  +0.00%
encoding/asn1                                1.41k ± 0%  1.42k ± 0%  +1.00%
encoding/base64                              1.67k ± 0%  1.69k ± 0%  +0.90%
encoding/binary                              2.65k ± 0%  2.76k ± 0%  +4.07%
encoding/gob                                 13.3k ± 0%  13.5k ± 0%  +1.65%
encoding/hex                                   854 ± 0%    857 ± 0%  +0.35%
encoding/json                                11.9k ± 0%  12.1k ± 0%  +1.71%
encoding/pem                                   484 ± 0%    484 ± 0%  +0.00%
errors                                         360 ± 0%    361 ± 0%  +0.28%
flag                                         7.32k ± 0%  7.42k ± 0%  +1.48%
fmt                                          1.42k ± 0%  1.42k ± 0%  +0.00%
go/ast                                       15.7k ± 0%  15.8k ± 0%  +1.07%
go/parser                                    7.48k ± 0%  7.59k ± 0%  +1.55%
go/scanner                                   3.88k ± 0%  3.94k ± 0%  +1.39%
go/token                                     3.51k ± 0%  3.53k ± 0%  +0.60%
hash                                           507 ± 0%    507 ± 0%  +0.00%
hash/crc32                                     685 ± 0%    685 ± 0%  +0.00%
internal/nettrace                              474 ± 0%    474 ± 0%  +0.00%
internal/pprof/profile                       8.29k ± 0%  8.36k ± 0%  +0.89%
internal/race                                  511 ± 0%    511 ± 0%  +0.00%
internal/singleflight                          966 ± 0%    969 ± 0%  +0.31%
internal/syscall/unix                          427 ± 0%    427 ± 0%  +0.00%
io                                           3.48k ± 0%  3.52k ± 0%  +1.15%
io/ioutil                                    5.30k ± 0%  5.38k ± 0%  +1.53%
log                                          4.46k ± 0%  4.53k ± 0%  +1.59%
math                                         3.72k ± 0%  3.75k ± 0%  +0.75%
math/big                                     8.91k ± 0%  9.01k ± 0%  +1.15%
math/rand                                    1.29k ± 0%  1.30k ± 0%  +0.46%
mime                                         2.59k ± 0%  2.63k ± 0%  +1.55%
mime/multipart                               3.61k ± 0%  3.68k ± 0%  +1.80%
mime/quotedprintable                         2.20k ± 0%  2.25k ± 0%  +2.50%
net                                          21.1k ± 0%  21.3k ± 0%  +1.10%
net/http                                     56.6k ± 0%  57.3k ± 0%  +1.28%
net/http/httptest                            33.6k ± 0%  34.1k ± 0%  +1.38%
net/http/httptrace                           14.4k ± 0%  14.5k ± 0%  +1.29%
net/http/internal                            2.70k ± 0%  2.77k ± 0%  +2.59%
net/textproto                                4.51k ± 0%  4.60k ± 0%  +1.82%
net/url                                      1.71k ± 0%  1.73k ± 0%  +1.41%
os                                           11.3k ± 0%  11.4k ± 0%  +1.36%
path                                           587 ± 0%    589 ± 0%  +0.34%
path/filepath                                4.46k ± 0%  4.55k ± 0%  +1.88%
reflect                                      6.39k ± 0%  6.43k ± 0%  +0.72%
regexp                                       5.82k ± 0%  5.88k ± 0%  +1.12%
regexp/syntax                                3.22k ± 0%  3.24k ± 0%  +0.62%
runtime                                      12.9k ± 0%  13.2k ± 0%  +1.94%
runtime/cgo                                    229 ± 0%    229 ± 0%  +0.00%
runtime/debug                                3.66k ± 0%  3.72k ± 0%  +1.86%
runtime/internal/atomic                        905 ± 0%    905 ± 0%  +0.00%
runtime/internal/sys                         2.00k ± 0%  2.05k ± 0%  +2.55%
runtime/pprof                                4.16k ± 0%  4.23k ± 0%  +1.66%
runtime/pprof/internal/protopprof            11.5k ± 0%  11.7k ± 0%  +1.27%
runtime/trace                                  354 ± 0%    354 ± 0%  +0.00%
sort                                         1.63k ± 0%  1.68k ± 0%  +2.94%
strconv                                      1.84k ± 0%  1.85k ± 0%  +0.54%
strings                                      3.87k ± 0%  3.97k ± 0%  +2.48%
sync                                         1.51k ± 0%  1.52k ± 0%  +0.33%
sync/atomic                                  1.58k ± 0%  1.60k ± 0%  +1.27%
syscall                                      53.2k ± 0%  53.3k ± 0%  +0.20%
testing                                      8.14k ± 0%  8.26k ± 0%  +1.49%
testing/internal/testdeps                      597 ± 0%    598 ± 0%  +0.17%
text/tabwriter                               3.09k ± 0%  3.14k ± 0%  +1.85%
text/template                                15.4k ± 0%  15.7k ± 0%  +1.89%
text/template/parse                          8.90k ± 0%  9.12k ± 0%  +2.46%
time                                         5.75k ± 0%  5.86k ± 0%  +1.86%
unicode                                      4.62k ± 0%  4.62k ± 0%  +0.07%
unicode/utf16                                  693 ± 0%    706 ± 0%  +1.88%
unicode/utf8                                 1.05k ± 0%  1.07k ± 0%  +1.14%
vendor/golang_org/x/crypto/chacha20poly1305  1.25k ± 0%  1.26k ± 0%  +0.64%
vendor/golang_org/x/crypto/curve25519          392 ± 0%    392 ± 0%  +0.00%
vendor/golang_org/x/crypto/poly1305            426 ± 0%    426 ± 0%  +0.00%
vendor/golang_org/x/net/http2/hpack          4.19k ± 0%  4.26k ± 0%  +1.69%
vendor/golang_org/x/net/idna                   355 ± 0%    355 ± 0%  +0.00%
vendor/golang_org/x/net/lex/httplex            609 ± 0%    615 ± 0%  +0.99%
vendor/golang_org/x/text/transform           1.31k ± 0%  1.31k ± 0%  +0.08%
vendor/golang_org/x/text/unicode/norm        5.78k ± 0%  5.90k ± 0%  +2.06%
vendor/golang_org/x/text/width               1.24k ± 0%  1.24k ± 0%  +0.16%
[Geo mean]                                    2.49k       2.52k       +1.10%

Fixes #18167.

Change-Id: Ia5b7e70adc9652c7ee9954ca2efc1c59fa79be2b
Reviewed-on: https://go-review.googlesource.com/33911
Run-TryBot: David Lazar <lazard@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
Reviewed-by: David Chase <drchase@google.com>
2017-02-08 20:59:45 +00:00
Cherry Zhang
160914e33c cmd/compile: do not use "oaslit" for global
The compiler did not emit write barrier for assigning global with
struct literal, like global = T{} where T contains pointer.

The relevant code path is:
walkexpr OAS var_ OSTRUCTLIT
    oaslit
        anylit OSTRUCTLIT
            walkexpr OAS var_ nil
            return without adding write barrier
    return true
break (without adding write barrier)

This CL makes oaslit not apply to globals. See also CL
https://go-review.googlesource.com/c/36355/ for an alternative
fix.

The downside of this is that it generates static data for zeroing
struct now. Also this only covers global. If there is any lurking
bug with implicit zeroing other than globals, this doesn't fix.

Fixes #18956.

Change-Id: Ibcd27e4fae3aa38390ffa94a32a9dd7a802e4b37
Reviewed-on: https://go-review.googlesource.com/36410
Reviewed-by: Russ Cox <rsc@golang.org>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-02-07 17:23:23 +00:00
Shintaro Kaneko
936749efb0 test: improve output format of issue10607a.go test
Change-Id: Iad5ff820a95f5082b75aa5260e40c33c7b0ecf22
Reviewed-on: https://go-review.googlesource.com/35990
Reviewed-by: Russ Cox <rsc@golang.org>
2017-02-07 14:00:27 +00:00
Robert Griesemer
3b68a64769 cmd/compile/internal/syntax: make a parser error "1.7 compliant"
For code such as

	if a := 10 { ...

the 1.7 compiler reported

	a := 10 used as value

while the 1.8 compiler reported

	invalid condition, tag, or type switch guard

Changed the error message to match the 1.7 compiler.

Fixes #18915.

Change-Id: I01308862e461922e717f9f8295a9db53d5a914eb
Reviewed-on: https://go-review.googlesource.com/36470
Run-TryBot: Robert Griesemer <gri@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-02-06 23:33:07 +00:00
Keith Randall
807c80fce3 cmd/compile: using CONV instead of CONVNOP for interface conversions
We shouldn't use CONVNOP for conversions between two different
nonempty interface types, because we want to update the itab
in those situations.

Fixes #18595

After this CL, we are guaranteed that itabs are unique, that is
there is only one itab per compile-time-type/concrete type pair.
See also the tests in CL 35115 and 35116 which make sure this
invariant holds even for shared libraries and plugins.

Unique itabs are required for CL 34810 (faster type switch code).

R=go1.9

Change-Id: Id27d2e01ded706680965e4cb69d7c7a24ac2161b
Reviewed-on: https://go-review.googlesource.com/35119
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2017-02-06 20:00:05 +00:00
Cherry Zhang
b53f0f8c96 cmd/compile: do not fold large offset on ARM64
Fixes #18933.

Change-Id: I8bb98e95bb4486a086d93bcf99e3a37488e77b03
Reviewed-on: https://go-review.googlesource.com/36318
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2017-02-04 16:46:11 +00:00
Michael Munday
ddf807fce8 cmd/compile: fix type propagation through s390x SSA rules
This CL fixes two issues:

1. Load ops were initially always lowered to unsigned loads, even
   for signed types. This was fine by itself however LoadReg ops
   (used to re-load spilled values) were lowered to signed loads
   for signed types. This meant that spills could invalidate
   optimizations that assumed the original unsigned load.

2. Types were not always being maintained correctly through rules
   designed to eliminate unnecessary zero and sign extensions.

Fixes #18906.

Change-Id: I95785dcadba03f7e3e94524677e7d8d3d3b9b737
Reviewed-on: https://go-review.googlesource.com/36256
Run-TryBot: Michael Munday <munday@ca.ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2017-02-03 21:27:21 +00:00
Keith Randall
8179b9b462 cmd/compile: make sure output params are live if there is a defer
If there is a defer, and that defer recovers, then the caller
can see all of the output parameters.  That means that we must
mark all the output parameters live at any point which might panic.

If there is no defer then this is not necessary.  This is implemented.

We could also detect whether there is a recover in any of the defers.
If not, we would need to mark only output params that the defer
actually references (and the closure mechanism already does that).
This is not implemented.

Fixes #18860.

Change-Id: If984fe6686eddce9408bf25e725dd17fc16b8578
Reviewed-on: https://go-review.googlesource.com/36030
Reviewed-by: Austin Clements <austin@google.com>
Reviewed-by: Russ Cox <rsc@golang.org>
2017-02-03 15:21:47 +00:00
Cherry Zhang
fddc004537 cmd/compile: remove nil check for Zero/Move on 386, AMD64, S390X
Fixes #18003.

Change-Id: Iadcc5c424c64badecfb5fdbd4dbd9197df56182c
Reviewed-on: https://go-review.googlesource.com/33421
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2017-02-02 21:28:38 +00:00
Robert Griesemer
c1363b2d91 cmd/compile: provide line number for cgo directive error (fix a TODO)
Also: Remove double "go:" prefix in related error message.

Fixes #18882.

Change-Id: Ifbbd8e2f7529b43f035d3dbf7ca4a91f212bc6b6
Reviewed-on: https://go-review.googlesource.com/36121
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2017-02-02 21:24:50 +00:00
Josh Bleecher Snyder
c682d3239e cmd/compile: convert constants to interfaces without allocating
The order pass is responsible for ensuring that
values passed to runtime functions, including
convT2E/convT2I, are addressable.

Prior to this CL, this was always accomplished
by creating a temp, which frequently escaped to
the heap, causing allocations, perhaps most
notably in code like:

fmt.Println(1, 2, 3) // allocates three times

None of the runtime routines modify the contents
of the pointers they receive, so in the case of
constants, instead of creating a temp value,
we can create a static value.

(Marking the static value as read-only provides
protection against accidental attempts by the runtime
to modify the constant data.)

This improves code generation for code like:

panic("abc")
c <- 2 // c is a chan int

which can now simply refer to "abc" and 2,
rather than going by way of a temporary.

It also allows us to optimize convT2E/convT2I,
by recognizing static readonly values
and directly constructing the interface.

This CL adds ~0.5% to binary size, despite
decreasing the size of many functions,
because it also adds many static symbols.

This binary size regression could be recovered in
future (but currently unplanned) work.

There is a lot of content-duplication in these
symbols; this statement generates six new symbols,
three containing an int 1 and three containing
a pointer to the string "a":

fmt.Println(1, 1, 1, "a", "a", "a")

These symbols could be made content-addressable.

Furthermore, these symbols are small, so the
alignment and naming overhead is large.
As with the go.strings section, these symbols
could be hidden and have their alignment reduced.

The changes to test/live.go make it impossible
(at least with current optimization techniques)
to place the values being passed to the runtime
in static symbols, preserving autotmp creation.

Fixes #18704

Benchmarks from fmt and go-kit's logging package:

github.com/go-kit/kit/log

name                      old time/op    new time/op    delta
JSONLoggerSimple-8          1.91µs ± 2%    2.11µs ±22%     ~     (p=1.000 n=9+10)
JSONLoggerContextual-8      2.60µs ± 6%    2.43µs ± 2%   -6.29%  (p=0.000 n=9+10)
Discard-8                    101ns ± 2%      34ns ±14%  -66.33%  (p=0.000 n=10+9)
OneWith-8                    161ns ± 1%     102ns ±16%  -36.78%  (p=0.000 n=10+10)
TwoWith-8                    175ns ± 3%     106ns ± 7%  -39.36%  (p=0.000 n=10+9)
TenWith-8                    293ns ± 3%     227ns ±15%  -22.44%  (p=0.000 n=9+10)
LogfmtLoggerSimple-8         704ns ± 2%     608ns ± 2%  -13.65%  (p=0.000 n=10+9)
LogfmtLoggerContextual-8     962ns ± 1%     860ns ±17%  -10.57%  (p=0.003 n=9+10)
NopLoggerSimple-8            188ns ± 1%     120ns ± 1%  -36.39%  (p=0.000 n=9+10)
NopLoggerContextual-8        379ns ± 1%     243ns ± 0%  -35.77%  (p=0.000 n=9+10)
ValueBindingTimestamp-8      577ns ± 1%     499ns ± 1%  -13.51%  (p=0.000 n=10+10)
ValueBindingCaller-8         898ns ± 2%     844ns ± 2%   -6.00%  (p=0.000 n=10+10)

name                      old alloc/op   new alloc/op   delta
JSONLoggerSimple-8            904B ± 0%      872B ± 0%   -3.54%  (p=0.000 n=10+10)
JSONLoggerContextual-8      1.20kB ± 0%    1.14kB ± 0%   -5.33%  (p=0.000 n=10+10)
Discard-8                    64.0B ± 0%     32.0B ± 0%  -50.00%  (p=0.000 n=10+10)
OneWith-8                    96.0B ± 0%     64.0B ± 0%  -33.33%  (p=0.000 n=10+10)
TwoWith-8                     160B ± 0%      128B ± 0%  -20.00%  (p=0.000 n=10+10)
TenWith-8                     672B ± 0%      640B ± 0%   -4.76%  (p=0.000 n=10+10)
LogfmtLoggerSimple-8          128B ± 0%       96B ± 0%  -25.00%  (p=0.000 n=10+10)
LogfmtLoggerContextual-8      304B ± 0%      240B ± 0%  -21.05%  (p=0.000 n=10+10)
NopLoggerSimple-8             128B ± 0%       96B ± 0%  -25.00%  (p=0.000 n=10+10)
NopLoggerContextual-8         304B ± 0%      240B ± 0%  -21.05%  (p=0.000 n=10+10)
ValueBindingTimestamp-8       159B ± 0%      127B ± 0%  -20.13%  (p=0.000 n=10+10)
ValueBindingCaller-8          112B ± 0%       80B ± 0%  -28.57%  (p=0.000 n=10+10)

name                      old allocs/op  new allocs/op  delta
JSONLoggerSimple-8            19.0 ± 0%      17.0 ± 0%  -10.53%  (p=0.000 n=10+10)
JSONLoggerContextual-8        25.0 ± 0%      21.0 ± 0%  -16.00%  (p=0.000 n=10+10)
Discard-8                     3.00 ± 0%      1.00 ± 0%  -66.67%  (p=0.000 n=10+10)
OneWith-8                     3.00 ± 0%      1.00 ± 0%  -66.67%  (p=0.000 n=10+10)
TwoWith-8                     3.00 ± 0%      1.00 ± 0%  -66.67%  (p=0.000 n=10+10)
TenWith-8                     3.00 ± 0%      1.00 ± 0%  -66.67%  (p=0.000 n=10+10)
LogfmtLoggerSimple-8          4.00 ± 0%      2.00 ± 0%  -50.00%  (p=0.000 n=10+10)
LogfmtLoggerContextual-8      7.00 ± 0%      3.00 ± 0%  -57.14%  (p=0.000 n=10+10)
NopLoggerSimple-8             4.00 ± 0%      2.00 ± 0%  -50.00%  (p=0.000 n=10+10)
NopLoggerContextual-8         7.00 ± 0%      3.00 ± 0%  -57.14%  (p=0.000 n=10+10)
ValueBindingTimestamp-8       5.00 ± 0%      3.00 ± 0%  -40.00%  (p=0.000 n=10+10)
ValueBindingCaller-8          4.00 ± 0%      2.00 ± 0%  -50.00%  (p=0.000 n=10+10)

fmt

name                             old time/op    new time/op    delta
SprintfPadding-8                   88.9ns ± 3%    79.1ns ± 1%   -11.09%  (p=0.000 n=10+7)
SprintfEmpty-8                     12.6ns ± 3%    12.8ns ± 3%      ~     (p=0.136 n=10+10)
SprintfString-8                    38.7ns ± 5%    26.9ns ± 6%   -30.65%  (p=0.000 n=10+10)
SprintfTruncateString-8            56.7ns ± 2%    47.0ns ± 3%   -17.05%  (p=0.000 n=10+10)
SprintfQuoteString-8                164ns ± 2%     153ns ± 2%    -7.01%  (p=0.000 n=10+10)
SprintfInt-8                       38.9ns ±15%    26.5ns ± 2%   -31.93%  (p=0.000 n=10+9)
SprintfIntInt-8                    60.3ns ± 9%    38.2ns ± 1%   -36.67%  (p=0.000 n=10+8)
SprintfPrefixedInt-8               58.6ns ±13%    51.2ns ±11%   -12.66%  (p=0.001 n=10+10)
SprintfFloat-8                     71.4ns ± 3%    64.2ns ± 3%   -10.08%  (p=0.000 n=8+10)
SprintfComplex-8                    175ns ± 3%     159ns ± 2%    -9.03%  (p=0.000 n=10+10)
SprintfBoolean-8                   33.5ns ± 4%    25.7ns ± 5%   -23.28%  (p=0.000 n=10+10)
SprintfHexString-8                 65.3ns ± 3%    51.7ns ± 5%   -20.86%  (p=0.000 n=10+9)
SprintfHexBytes-8                  67.2ns ± 5%    67.9ns ± 4%      ~     (p=0.383 n=10+10)
SprintfBytes-8                      129ns ± 7%     124ns ± 7%      ~     (p=0.074 n=9+10)
SprintfStringer-8                   127ns ± 4%     126ns ± 8%      ~     (p=0.506 n=9+10)
SprintfStructure-8                  357ns ± 3%     359ns ± 3%      ~     (p=0.469 n=10+10)
ManyArgs-8                          203ns ± 6%     126ns ± 3%   -37.94%  (p=0.000 n=10+10)
FprintInt-8                         119ns ±10%      74ns ± 3%   -37.54%  (p=0.000 n=10+10)
FprintfBytes-8                      122ns ± 4%     120ns ± 3%      ~     (p=0.124 n=10+10)
FprintIntNoAlloc-8                 78.2ns ± 5%    74.1ns ± 3%    -5.28%  (p=0.000 n=10+10)
ScanInts-8                          349µs ± 1%     349µs ± 0%      ~     (p=0.606 n=9+8)
ScanRecursiveInt-8                 43.8ms ± 7%    40.1ms ± 2%    -8.42%  (p=0.000 n=10+10)
ScanRecursiveIntReaderWrapper-8    43.5ms ± 4%    40.4ms ± 2%    -7.16%  (p=0.000 n=10+9)

name                             old alloc/op   new alloc/op   delta
SprintfPadding-8                    24.0B ± 0%     16.0B ± 0%   -33.33%  (p=0.000 n=10+10)
SprintfEmpty-8                      0.00B          0.00B           ~     (all equal)
SprintfString-8                     21.0B ± 0%      5.0B ± 0%   -76.19%  (p=0.000 n=10+10)
SprintfTruncateString-8             32.0B ± 0%     16.0B ± 0%   -50.00%  (p=0.000 n=10+10)
SprintfQuoteString-8                48.0B ± 0%     32.0B ± 0%   -33.33%  (p=0.000 n=10+10)
SprintfInt-8                        16.0B ± 0%      1.0B ± 0%   -93.75%  (p=0.000 n=10+10)
SprintfIntInt-8                     24.0B ± 0%      3.0B ± 0%   -87.50%  (p=0.000 n=10+10)
SprintfPrefixedInt-8                72.0B ± 0%     64.0B ± 0%   -11.11%  (p=0.000 n=10+10)
SprintfFloat-8                      16.0B ± 0%      8.0B ± 0%   -50.00%  (p=0.000 n=10+10)
SprintfComplex-8                    48.0B ± 0%     32.0B ± 0%   -33.33%  (p=0.000 n=10+10)
SprintfBoolean-8                    8.00B ± 0%     4.00B ± 0%   -50.00%  (p=0.000 n=10+10)
SprintfHexString-8                  96.0B ± 0%     80.0B ± 0%   -16.67%  (p=0.000 n=10+10)
SprintfHexBytes-8                    112B ± 0%      112B ± 0%      ~     (all equal)
SprintfBytes-8                      96.0B ± 0%     96.0B ± 0%      ~     (all equal)
SprintfStringer-8                   32.0B ± 0%     32.0B ± 0%      ~     (all equal)
SprintfStructure-8                   256B ± 0%      256B ± 0%      ~     (all equal)
ManyArgs-8                          80.0B ± 0%      0.0B       -100.00%  (p=0.000 n=10+10)
FprintInt-8                         8.00B ± 0%     0.00B       -100.00%  (p=0.000 n=10+10)
FprintfBytes-8                      32.0B ± 0%     32.0B ± 0%      ~     (all equal)
FprintIntNoAlloc-8                  0.00B          0.00B           ~     (all equal)
ScanInts-8                         15.2kB ± 0%    15.2kB ± 0%      ~     (p=0.248 n=9+10)
ScanRecursiveInt-8                 21.6kB ± 0%    21.6kB ± 0%      ~     (all equal)
ScanRecursiveIntReaderWrapper-8    21.7kB ± 0%    21.7kB ± 0%      ~     (all equal)

name                             old allocs/op  new allocs/op  delta
SprintfPadding-8                     2.00 ± 0%      1.00 ± 0%   -50.00%  (p=0.000 n=10+10)
SprintfEmpty-8                       0.00           0.00           ~     (all equal)
SprintfString-8                      2.00 ± 0%      1.00 ± 0%   -50.00%  (p=0.000 n=10+10)
SprintfTruncateString-8              2.00 ± 0%      1.00 ± 0%   -50.00%  (p=0.000 n=10+10)
SprintfQuoteString-8                 2.00 ± 0%      1.00 ± 0%   -50.00%  (p=0.000 n=10+10)
SprintfInt-8                         2.00 ± 0%      1.00 ± 0%   -50.00%  (p=0.000 n=10+10)
SprintfIntInt-8                      3.00 ± 0%      1.00 ± 0%   -66.67%  (p=0.000 n=10+10)
SprintfPrefixedInt-8                 2.00 ± 0%      1.00 ± 0%   -50.00%  (p=0.000 n=10+10)
SprintfFloat-8                       2.00 ± 0%      1.00 ± 0%   -50.00%  (p=0.000 n=10+10)
SprintfComplex-8                     2.00 ± 0%      1.00 ± 0%   -50.00%  (p=0.000 n=10+10)
SprintfBoolean-8                     2.00 ± 0%      1.00 ± 0%   -50.00%  (p=0.000 n=10+10)
SprintfHexString-8                   2.00 ± 0%      1.00 ± 0%   -50.00%  (p=0.000 n=10+10)
SprintfHexBytes-8                    2.00 ± 0%      2.00 ± 0%      ~     (all equal)
SprintfBytes-8                       2.00 ± 0%      2.00 ± 0%      ~     (all equal)
SprintfStringer-8                    4.00 ± 0%      4.00 ± 0%      ~     (all equal)
SprintfStructure-8                   7.00 ± 0%      7.00 ± 0%      ~     (all equal)
ManyArgs-8                           8.00 ± 0%      0.00       -100.00%  (p=0.000 n=10+10)
FprintInt-8                          1.00 ± 0%      0.00       -100.00%  (p=0.000 n=10+10)
FprintfBytes-8                       1.00 ± 0%      1.00 ± 0%      ~     (all equal)
FprintIntNoAlloc-8                   0.00           0.00           ~     (all equal)
ScanInts-8                          1.60k ± 0%     1.60k ± 0%      ~     (all equal)
ScanRecursiveInt-8                  1.71k ± 0%     1.71k ± 0%      ~     (all equal)
ScanRecursiveIntReaderWrapper-8     1.71k ± 0%     1.71k ± 0%      ~     (all equal)

Change-Id: I7ba72a25fea4140a0ba40a9f443103ed87cc69b5
Reviewed-on: https://go-review.googlesource.com/35554
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2017-02-02 21:02:23 +00:00
Keith Randall
73f92f9b04 cmd/compile: use len(s)<=cap(s) to remove more bounds checks
When we discover a relation x <= len(s), also discover the relation
x <= cap(s).  That way, in situations like:

a := s[x:]  // tests 0 <= x <= len(s)
b := s[:x]  // tests 0 <= x <= cap(s)

the second check can be eliminated.

Fixes #16813

Change-Id: Ifc037920b6955e43bac1a1eaf6bac63a89cfbd44
Reviewed-on: https://go-review.googlesource.com/33633
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Alexandru Moșoi <alexandru@mosoi.ro>
Reviewed-by: David Chase <drchase@google.com>
2017-02-02 17:45:58 +00:00
Keith Randall
6317f92f6e cmd/compile: fix CSE with commutative ops
CSE opportunities were being missed for commutative ops. We used to
order the args of commutative ops (by arg ID) once at the start of CSE.
But that may not be enough.

i1 = (Load ptr mem)
i2 = (Load ptr mem)
x1 = (Add i1 j)
x2 = (Add i2 j)

Equivalent commutative ops x1 and x2 may not get their args ordered in
the same way because because at the start of CSE, we don't know that
the i values will be CSEd. If x1 and x2 get opposite orders we won't
CSE them.

Instead, (re)order the args of commutative operations by their
equivalence class IDs each time we partition an equivalence class.

Change-Id: Ic609fa83b85299782a5e85bf93dc6023fccf4b0c
Reviewed-on: https://go-review.googlesource.com/33632
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Todd Neal <todd@tneal.org>
2017-02-02 17:45:43 +00:00
Emmanuel Odeke
34b563f447 cmd/compile: improve error for wrong type in switch
Fixes #10561.

Provides a better diagnostic message for failed type switch
satisfaction in the case that a value receiver is being used
in place of the pointer receiver that implements and satisfies
the interface.

Change-Id: If8c13ba13f2a8d81bf44bac7c3a66c12921ba921
Reviewed-on: https://go-review.googlesource.com/35235
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-02-02 17:36:43 +00:00
Emmanuel Odeke
cb6e0639fb cmd/compile: improve error message if init is directly invoked
Fixes #8481.

Inform the user that init functions cannot be directly invoked
in user code, as mandated by the spec at:
http://golang.org/ref/spec#Program_initialization_and_execution.

Change-Id: Ib12c0c08718ffd48b76b6f9b13c76bb6612d2e7b
Reviewed-on: https://go-review.googlesource.com/34790
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-02-02 05:55:03 +00:00
Emmanuel Odeke
dba0d38298 cmd/compile: fix conversion error message for printed slices
Fixes #15055.

Updates exprfmt printing using fmt verb "%v" to check that n.Left
is non-nil before attempting to print it, otherwise we'll print
the nodes in the list using verb "%.v".

Credit to @mdempsky for this approach and for finding
the root cause of the issue.

Change-Id: I20a6464e916dc70d5565e145164bb9553e5d3865
Reviewed-on: https://go-review.googlesource.com/25361
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-02-02 05:10:22 +00:00
Josh Bleecher Snyder
b443babad4 test: add extra test for issue18661
Make sure that the lack of an lvalue doesn't
cause extra side-effects.

Updates #18661
Updates #18739

Change-Id: I52eb4b4a5c6f8ff5cddd2115455f853c18112c19
Reviewed-on: https://go-review.googlesource.com/36126
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2017-02-02 04:57:33 +00:00
Matthew Dempsky
16dd0624c2 cmd/compile/internal/gc: add comment and test for #15550
When switching to the new parser, I changed cmd/compile to handle iota
per an intuitive interpretation of how nested constant declarations
should work (which also matches go/types).

Note: if we end up deciding that the current spec wording is
intentional (i.e., confirming gccgo's current behavior), the test will
need to be updated to expect 4 instead of 1.

Updates #15550.

Change-Id: I441f5f13209f172b73ef75031f2a9daa5e985277
Reviewed-on: https://go-review.googlesource.com/36122
Reviewed-by: David Crawshaw <crawshaw@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-02-02 04:25:23 +00:00
Matthew Dempsky
a27b78141b cmd/compile/internal/gc: inline typedcl0 and typedcl1
It's easier to understand what's happening after inlining these into
noder.typeDecl.

Change-Id: I7beed5a1e18047bf09f2d4ddf64b9646c324d8d6
Reviewed-on: https://go-review.googlesource.com/36111
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
2017-02-01 22:52:32 +00:00
Alberto Donizetti
871300308a cmd/compile: never report "truncated to real" for toint calls
Whoever called toint() is expecting the {Mpint, Mpflt, Mpcplx} arg to
be converted to an integer expression, so it never makes sense to
report an error as "constant X truncated to real".

Fixes #11580

Change-Id: Iadcb105f0802358a7f77188c2b1e63fe80c5580c
Reviewed-on: https://go-review.googlesource.com/34638
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
Run-TryBot: Robert Griesemer <gri@golang.org>
2017-02-01 21:22:50 +00:00
Russ Cox
47ce87877b all: merge dev.inline into master
Change-Id: I7715581a04e513dcda9918e853fa6b1ddc703770
2017-02-01 09:47:23 -05:00
Russ Cox
c47df7ae17 all: merge dev.typealias into master
For #18130.

f8b4123613 [dev.typealias] spec: use term 'embedded field' rather than 'anonymous field'
9ecc3ee252 [dev.typealias] cmd/compile: avoid false positive cycles from type aliases
49b7af8a30 [dev.typealias] reflect: add test for type aliases
9bbb07ddec [dev.typealias] cmd/compile, reflect: fix struct field names for embedded byte, rune
43c7094386 [dev.typealias] reflect: fix StructOf use of StructField to match StructField docs
9657e0b077 [dev.typealias] cmd/doc: update for type alias
de2e5459ae [dev.typealias] cmd/compile: declare methods after resolving receiver type
9259f3073a [dev.typealias] test: match gccgo error messages on alias2.go
5d92916770 [dev.typealias] cmd/compile: change Func.Shortname to *Sym
a7c884efc1 [dev.typealias] go/internal/gccgoimporter: support for type aliases
5802cfd900 [dev.typealias] cmd/compile: export/import test cases for type aliases
d7cabd40dd [dev.typealias] go/types: clarified doc string
cc2dcce3d7 [dev.typealias] cmd/compile: a few better comments related to alias types
5c160b28ba [dev.typealias] cmd/compile: improved error message for cyles involving type aliases
b2386dffa1 [dev.typealias] cmd/compile: type-check type alias declarations
ac8421f9a5 [dev.typealias] cmd/compile: various minor cleanups
f011e0c6c3 [dev.typealias] cmd/compile, go/types, go/importer: various alias related fixes
49de5f0351 [dev.typealias] cmd/compile, go/importer: define export format and implement importing of type aliases
5ceec42dc0 [dev.typealias] go/types: export TypeName.IsAlias so clients can use it
aa1f0681bc [dev.typealias] go/types: improved Object printing
c80748e389 [dev.typealias] go/types: remove some more vestiges of prior alias implementation
80d8b69e95 [dev.typealias] go/types: implement type aliases
a917097b5e [dev.typealias] go/build: add go1.9 build tag
3e11940437 [dev.typealias] cmd/compile: recognize type aliases but complain for now (not yet supported)
e0a05c274a [dev.typealias] cmd/gofmt: added test cases for alias type declarations
2e5116bd99 [dev.typealias] go/ast, go/parser, go/printer, go/types: initial type alias support

Change-Id: Ia65f2e011fd7195f18e1dce67d4d49b80a261203
2017-01-31 13:01:31 -05:00
Michael Munday
96ea0918e6 cmd/compile: use CMPWU for 32-bit or smaller unsigned Geq on ppc64{,le}
Fixes #18808.

Change-Id: I49b266380b9d6804c9f6563ebac9c7c0e05f37f6
Reviewed-on: https://go-review.googlesource.com/35890
Run-TryBot: Michael Munday <munday@ca.ibm.com>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2017-01-27 16:04:04 +00:00
Matthew Dempsky
9ecc3ee252 [dev.typealias] cmd/compile: avoid false positive cycles from type aliases
For #18130.
Fixes #18640.

Change-Id: I26cf1d1b78cca6ef207cc4333f30a9011ef347c9
Reviewed-on: https://go-review.googlesource.com/35831
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
2017-01-26 18:35:13 +00:00
Matthew Dempsky
de2e5459ae [dev.typealias] cmd/compile: declare methods after resolving receiver type
For #18130.
Fixes #18655.

Change-Id: I58e2f076b9d8273f128cc033bba9edcd06c81567
Reviewed-on: https://go-review.googlesource.com/35575
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
2017-01-25 08:04:17 +00:00
Ian Lance Taylor
9259f3073a [dev.typealias] test: match gccgo error messages on alias2.go
For #18130.

Change-Id: I9561ee2b8a9f7b11f0851f281a899f78b9e9703e
Reviewed-on: https://go-review.googlesource.com/35640
Reviewed-by: Robert Griesemer <gri@golang.org>
2017-01-24 22:51:50 +00:00
Keith Randall
256a605faa cmd/compile: don't use nilcheck information until the next block
When nilcheck runs, the values in a block are not in any particular
order.  So any facts derived from examining the blocks shouldn't be
used until we reach the next block.

This is suboptimal as it won't eliminate nil checks within a block.
But it's probably a better fix for now as it is a much smaller change
than other strategies for fixing this bug.

nilptr3.go changes are mostly because for this pattern:
  _ = *p
  _ = *p
either nil check is fine to keep, and this CL changes which one
the compiler tends to keep.
There are a few regressions from code like this:
  _ = *p
  f()
  _ = *p
For this pattern, after this CL we issue 2 nil checks instead of one.
(For the curious, this happens because intra-block nil check
 elimination now falls to CSE, not nilcheck proper.  The former
 pattern has two nil checks with the same store argument.  The latter
 pattern has two nil checks with different store arguments.)

Fixes #18725

Change-Id: I3721b494c8bc9ba1142dc5c4361ea55c66920ac8
Reviewed-on: https://go-review.googlesource.com/35485
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2017-01-20 20:21:55 +00:00
Robert Griesemer
5802cfd900 [dev.typealias] cmd/compile: export/import test cases for type aliases
Plus a few minor changes.

For #18130.

Change-Id: Ica6503fe9c888cc05c15b46178423f620c087491
Reviewed-on: https://go-review.googlesource.com/35233
Reviewed-by: Alan Donovan <adonovan@google.com>
2017-01-20 05:55:53 +00:00
Josh Bleecher Snyder
5b708a6b6a cmd/compile: lvalues are only required for == when calling runtime fns
Fixes #18661.

Change-Id: I865802a9b88ab22560c9914a70901d1924242bdc
Reviewed-on: https://go-review.googlesource.com/35236
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2017-01-16 05:40:45 +00:00
Robert Griesemer
b2386dffa1 [dev.typealias] cmd/compile: type-check type alias declarations
Known issues:
- needs many more tests
- duplicate method declarations via type alias names are not detected
- type alias cycle error messages need to be improved
- need to review setup of byte/rune type aliases

For #18130.

Change-Id: Icc2fefad6214e5e56539a9dcb3fe537bf58029f8
Reviewed-on: https://go-review.googlesource.com/35121
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2017-01-12 21:58:33 +00:00
David Chase
d9a0579156 cmd/compile: disable flaky test
The test is inherently racy and vulnerable to starvation,
and within all.bash on some platforms that means it flakes.
Test is kept because it can be useful standalone to verify
behavior of GOEXPERIMENT=preeemptibleloops, and there is
likely to be further development of this feature in the
future.

There's also some question as to why it is flaking, because
though technically this is permitted, it's very odd in this
simple case.

Fixes #18589.

Change-Id: Ia0dd9037285c4a03122da4012c96981c9cc43b60
Reviewed-on: https://go-review.googlesource.com/35051
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2017-01-10 17:29:46 +00:00
Robert Griesemer
3e11940437 [dev.typealias] cmd/compile: recognize type aliases but complain for now (not yet supported)
Added test file.

For #18130.

Change-Id: Ifcfd7cd1acf9dd6a2f4f3d85979d232bb6b8c6b1
Reviewed-on: https://go-review.googlesource.com/34988
Run-TryBot: Robert Griesemer <gri@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-01-10 00:10:11 +00:00
David Chase
7f1ff65c39 cmd/compile: insert scheduling checks on loop backedges
Loop breaking with a counter.  Benchmarked (see comments),
eyeball checked for sanity on popular loops.  This code
ought to handle loops in general, and properly inserts phi
functions in cases where the earlier version might not have.

Includes test, plus modifications to test/run.go to deal with
timeout and killing looping test.  Tests broken by the addition
of extra code (branch frequency and live vars) for added
checks turn the check insertion off.

If GOEXPERIMENT=preemptibleloops, the compiler inserts reschedule
checks on every backedge of every reducible loop.  Alternately,
specifying GO_GCFLAGS=-d=ssa/insert_resched_checks/on will
enable it for a single compilation, but because the core Go
libraries contain some loops that may run long, this is less
likely to have the desired effect.

This is intended as a tool to help in the study and diagnosis
of GC and other latency problems, now that goal STW GC latency
is on the order of 100 microseconds or less.

Updates #17831.
Updates #10958.

Change-Id: I6206c163a5b0248e3f21eb4fc65f73a179e1f639
Reviewed-on: https://go-review.googlesource.com/33910
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2017-01-09 21:01:29 +00:00
Robert Griesemer
f412bd31ce cmd/compile: file line number for //go:xxx directives
Minimally invasive; fixes a regression from 1.7.

Fixes #18459.

Change-Id: I93b3b5c05706eaff8ae97a237f770838c1f8778c
Reviewed-on: https://go-review.googlesource.com/34721
Reviewed-by: David Chase <drchase@google.com>
Reviewed-by: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2017-01-09 19:39:56 +00:00
David Chase
41d2278eef cmd/compile: rewrite literal.method to ensure full initialization
CALLPART of STRUCTLIT did not check for incomplete initialization
of struct; modify PTRLIT treatment to force zeroing.

Test for structlit, believe this might have also failed for
arraylit.

Fixes #18410.

Change-Id: I511abf8ef850e300996d40568944665714efe1fc
Reviewed-on: https://go-review.googlesource.com/34622
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2017-01-06 20:35:52 +00:00
Emmanuel Odeke
b03dce927b cmd/compile: avoid n.Right nil dereference on non-existent interface methods
Fixes #18392.

Avoid nil dereferencing n.Right when dealing with non-existent
self referenced interface methods e.g.
type A interface{
  Fn(A.Fn)
}

Instead, infer the symbol name from n.Sym itself.

Change-Id: I60d5f8988e7318693e5c8da031285d8d7347b771
Reviewed-on: https://go-review.googlesource.com/34817
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2017-01-05 22:09:25 +00:00
Emmanuel Odeke
5bfba30d33 cmd/compile: lock-in test for repeated variables in range declaration
Fixes #6772.

Lock-in test for invalid range loop: repeated variables in range declaration.

Change-Id: I37dd8b1cd7279abe7810deaf8a5d485c5c3b73ca
Reviewed-on: https://go-review.googlesource.com/34714
Reviewed-by: Keith Randall <khr@golang.org>
2016-12-24 22:37:11 +00:00
Emmanuel Odeke
c8f1436948 test: lock in test for _ assignment evaluation/zerodivide panic
Fixes #5790.
Fixes #18421.

* Lock in _ = x1/x2 divide by zero runtime panics since
it is actually evaluated and not discarded as in previous
versions before Go1.8.
* Update a test that was skipping over zerodivide tests
that expected runtime panics, enabling us to check for
the expected panics.

Change-Id: I0af0a6ecc19345fa9763ab2e35b275fb2d9d0194
Reviewed-on: https://go-review.googlesource.com/34712
Reviewed-by: Keith Randall <khr@golang.org>
2016-12-23 17:35:24 +00:00
Vladimir Stefanovic
0cd2bf4f98 test: add mipsx case to nosplit.go
Change-Id: I496bceacb6b3f417e36dc725d988b12c59a200d5
Reviewed-on: https://go-review.googlesource.com/34412
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-12-15 22:43:28 +00:00
Ian Lance Taylor
6e542dce21 test: add test gcc78763.go that caused a gccgo compiler crash
Change-Id: I0d990d494ee8eebfc804b526f5ced71944572b4d
Reviewed-on: https://go-review.googlesource.com/34491
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-12-15 22:42:33 +00:00
Vladimir Stefanovic
01b006fc18 test/fixedbugs: add mipsx case to issue11656
Change-Id: Ifcbd2ea19fc7fa832cd88aa857a5704c32eb4765
Reviewed-on: https://go-review.googlesource.com/34511
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-12-15 16:57:20 +00:00
Vladimir Stefanovic
49e5bdfe79 test: enable fixedbugs/issue10607 test on GOARCH=mips{,le}
Change-Id: I00c97c36e8fdc79582eaed21877e4c8f44568666
Reviewed-on: https://go-review.googlesource.com/34316
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-12-15 00:12:31 +00:00
Vladimir Stefanovic
48b42d29dc test/bench/go1: reduce fasta data size for mips{,64}
Change-Id: I15887ee454acfdb36334dd9f0b59cc520b2b0286
Reviewed-on: https://go-review.googlesource.com/34311
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2016-12-13 22:04:23 +00:00
Robert Griesemer
4b8895e2dd [dev.inline] cmd/compile/internal/syntax: remove gcCompat uses in scanner
- make the scanner unconditionally gc compatible
- consistently use "invalid" instead "illegal" in errors

Reviewed in and cherry-picked from https://go-review.googlesource.com/#/c/33896/.

Change-Id: I4c4253e7392f3311b0d838bbe503576c9469b203
Reviewed-on: https://go-review.googlesource.com/34237
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2016-12-09 01:35:23 +00:00
Brad Fitzpatrick
4c4201f0e2 all: make spelling consistent
Fixes #17938

Change-Id: Iad12155f4976846bd4a9a53869f89e40e5b3deb3
Reviewed-on: https://go-review.googlesource.com/34147
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Joe Tsai <thebrokentoaster@gmail.com>
2016-12-08 23:22:37 +00:00
Ian Lance Taylor
51a6d3e074 test: add bug501.go, a gccgo compiler crash
Change-Id: I271707dee03fd97cd37bfb116eb00a5532034b57
Reviewed-on: https://go-review.googlesource.com/34020
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2016-12-07 21:55:00 +00:00
Matthew Dempsky
749720a036 cmd/compile: fix static-initialization compilation failure
Fixes #13263.

Change-Id: Ie1cafc62b6bfe6c5381c35d9a95563267b4cc9b0
Reviewed-on: https://go-review.googlesource.com/33970
Reviewed-by: Robert Griesemer <gri@golang.org>
Reviewed-by: Emmanuel Odeke <emm.odeke@gmail.com>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-12-06 06:14:59 +00:00
Ian Lance Taylor
6270c5ac28 test: add test case for which gccgo generated incorrect GC info
Change-Id: I5e33db9e63f70706882b85ab124a48509797b05a
Reviewed-on: https://go-review.googlesource.com/33790
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2016-12-02 21:29:37 +00:00
Robert Griesemer
2d136ae82e cmd/compile: correctly parse //line filename:line where filename contains ':'
This was a regression from 1.7. See the issue for details.

Fixes #18149.

Change-Id: Ic8f5a35d14edf9254b1275400316cff7aff32a27
Reviewed-on: https://go-review.googlesource.com/33799
Run-TryBot: Robert Griesemer <gri@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-12-01 22:01:33 +00:00
David Lazar
5d1b53a944 cmd/compile: generate code that type checks when inlining variadic functions
This fixes a bug in -l=3 or higher.

To inline a variadic function, the compiler generates code that constructs
a slice of arguments for the variadic parameter. Consider the function

  func Foo(xs ...string)

and the call Foo("hello", "world"). To inline the call to Foo, the
compiler used to generate

  xs := [2]string{"hello", "world"}[:]

which doesn't type check:

  invalid operation [2]string literal[:] (slice of unaddressable value).

Now, the compiler generates

  xs := []string{"hello", "world"}

which does type check.

Fixes #18116.

Change-Id: I0ee531ef2e6cc276db6fb12602b25a46d6d5db21
Reviewed-on: https://go-review.googlesource.com/33671
Reviewed-by: Keith Randall <khr@golang.org>
2016-11-30 19:46:00 +00:00
Robert Griesemer
8fa0d85b38 cmd/compile: don't panic on syntax error in select statement
Fixes #18092.

Change-Id: I54e2da2e0f168c068f5e4a1b22ba508d78259168
Reviewed-on: https://go-review.googlesource.com/33658
TryBot-Result: Gobot Gobot <gobot@golang.org>
Run-TryBot: Robert Griesemer <gri@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2016-11-29 16:47:34 +00:00
Brad Fitzpatrick
c2bb52b830 test: remove amd64 build tag from test
It was supposed to be testing SSA, not amd64.

For #18024

Change-Id: Ibe65d7eb6bed9bc4b3eda68e1eaec5fa39fe8f76
Reviewed-on: https://go-review.googlesource.com/33491
Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
2016-11-23 22:01:32 +00:00
Philip Hofer
a34fddf46c cmd/compile: in cse, allow for new ssa values
The table of rewrites in ssa/cse is not sized appropriately for
ssa IDs that are created during copying of selects into new blocks.

Fixes #17918

Change-Id: I65fe86c6aab5efa679aa473aadc4ee6ea882cd41
Reviewed-on: https://go-review.googlesource.com/33240
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Reviewed-by: David Chase <drchase@google.com>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-11-18 16:31:27 +00:00
Ian Lance Taylor
4d1fdd8b5e test: add test case that failed when built with gccgo
Change-Id: Ie7512cc27436cde53b58686b32a0389849a365e4
Reviewed-on: https://go-review.googlesource.com/33249
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2016-11-15 21:25:44 +00:00
Dmitri Shuralyov
d8264de868 all: spell "marshal" and "unmarshal" consistently
The tree is inconsistent about single l vs double l in those
words in documentation, test messages, and one error value text.

	$ git grep -E '[Mm]arshall(|s|er|ers|ed|ing)' | wc -l
	      42
	$ git grep -E '[Mm]arshal(|s|er|ers|ed|ing)' | wc -l
	    1694

Make it consistently a single l, per earlier decisions. This means
contributors won't be confused by misleading precedence, and it helps
consistency.

Change the spelling in one error value text in newRawAttributes of
crypto/x509 package to be consistent.

This change was generated with:

	perl -i -npe 's,([Mm]arshal)l(|s|er|ers|ed|ing),$1$2,' $(git grep -l -E '[Mm]arshall' | grep -v AUTHORS | grep -v CONTRIBUTORS)

Updates #12431.
Follows https://golang.org/cl/14150.

Change-Id: I85d28a2d7692862ccb02d6a09f5d18538b6049a2
Reviewed-on: https://go-review.googlesource.com/33017
Run-TryBot: Minux Ma <minux@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2016-11-12 00:13:35 +00:00
Michael Munday
6c2a35ae0c test/fixedbugs: enable issue 10607 test on ppc64le
ppc64le supports both internal and external linking so I don't
think there is any reason for it to skip this test.

Change-Id: I05c80cc25909c0364f0a1fb7d20766b011ea1ebb
Reviewed-on: https://go-review.googlesource.com/32854
Reviewed-by: Lynn Boger <laboger@linux.vnet.ibm.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-11-07 18:42:57 +00:00
Robert Griesemer
8e970536df cmd/compile: revert user-visible changes related to aliases
Reason: Decision to back out current alias implementation.

Leaving import/export related code in place for now.

For #16339.

TBR=mdempsky

Change-Id: Ib0897cab2c1c3dc8a541f2efb9893271b0b0efe2
Reviewed-on: https://go-review.googlesource.com/32757
Reviewed-by: Robert Griesemer <gri@golang.org>
2016-11-04 23:44:15 +00:00