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Commit Graph

2651 Commits

Author SHA1 Message Date
Matthew Dempsky
ec5b6406b7 cmd/compile: improve not enough / too many arguments errors
Use "have" and "want" and multiple lines like other similar error
messages. Also, fix handling of ... and multi-value function calls.

Fixes #17650.

Change-Id: I4850e79c080eac8df3b92a4accf9e470dff63c9a
Reviewed-on: https://go-review.googlesource.com/32261
Reviewed-by: Robert Griesemer <gri@golang.org>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-10-28 21:53:07 +00:00
Austin Clements
c39918a049 cmd/compile: disable various write barrier optimizations
Several of our current write barrier elision optimizations are invalid
with the hybrid barrier. Eliding the hybrid barrier requires that
*both* the current and new pointer be already shaded and, since we
don't have the flow analysis to figure out anything about the slot's
current value, for now we have to just disable several of these
optimizations.

This has a slight impact on binary size. On linux/amd64, the go tool
binary increases by 0.7% and the compile binary increases by 1.5%.

It also has a slight impact on performance, as one would expect. We'll
win some of this back in subsequent commits.

name                      old time/op    new time/op    delta
BinaryTree17-12              2.38s ± 1%     2.40s ± 1%  +0.82%  (p=0.000 n=18+20)
Fannkuch11-12                2.84s ± 1%     2.70s ± 0%  -4.97%  (p=0.000 n=18+18)
FmtFprintfEmpty-12          44.2ns ± 1%    46.4ns ± 2%  +4.89%  (p=0.000 n=16+18)
FmtFprintfString-12          131ns ± 0%     134ns ± 1%  +2.05%  (p=0.000 n=12+19)
FmtFprintfInt-12             114ns ± 1%     117ns ± 1%  +3.26%  (p=0.000 n=19+20)
FmtFprintfIntInt-12          176ns ± 1%     181ns ± 1%  +3.25%  (p=0.000 n=20+20)
FmtFprintfPrefixedInt-12     185ns ± 1%     190ns ± 1%  +2.77%  (p=0.000 n=19+18)
FmtFprintfFloat-12           249ns ± 1%     254ns ± 1%  +1.71%  (p=0.000 n=18+20)
FmtManyArgs-12               747ns ± 1%     743ns ± 1%  -0.58%  (p=0.000 n=19+18)
GobDecode-12                6.57ms ± 1%    6.61ms ± 0%  +0.73%  (p=0.000 n=19+20)
GobEncode-12                5.58ms ± 1%    5.60ms ± 0%  +0.27%  (p=0.001 n=18+18)
Gzip-12                      223ms ± 1%     223ms ± 1%    ~     (p=0.351 n=19+20)
Gunzip-12                   37.9ms ± 0%    37.9ms ± 1%    ~     (p=0.095 n=16+20)
HTTPClientServer-12         77.8µs ± 1%    78.5µs ± 1%  +0.97%  (p=0.000 n=19+20)
JSONEncode-12               14.8ms ± 1%    14.8ms ± 1%    ~     (p=0.079 n=20+19)
JSONDecode-12               53.7ms ± 1%    54.2ms ± 1%  +0.92%  (p=0.000 n=20+19)
Mandelbrot200-12            3.81ms ± 1%    3.81ms ± 0%    ~     (p=0.916 n=19+18)
GoParse-12                  3.19ms ± 1%    3.19ms ± 1%    ~     (p=0.175 n=20+19)
RegexpMatchEasy0_32-12      71.9ns ± 1%    70.6ns ± 1%  -1.87%  (p=0.000 n=19+20)
RegexpMatchEasy0_1K-12       946ns ± 0%     944ns ± 0%  -0.22%  (p=0.000 n=19+16)
RegexpMatchEasy1_32-12      67.3ns ± 2%    66.8ns ± 1%  -0.72%  (p=0.008 n=20+20)
RegexpMatchEasy1_1K-12       374ns ± 1%     384ns ± 1%  +2.69%  (p=0.000 n=18+20)
RegexpMatchMedium_32-12      107ns ± 1%     107ns ± 1%    ~     (p=1.000 n=20+20)
RegexpMatchMedium_1K-12     34.3µs ± 1%    34.6µs ± 1%  +0.90%  (p=0.000 n=20+20)
RegexpMatchHard_32-12       1.78µs ± 1%    1.80µs ± 1%  +1.45%  (p=0.000 n=20+19)
RegexpMatchHard_1K-12       53.6µs ± 0%    54.5µs ± 1%  +1.52%  (p=0.000 n=19+18)
Revcomp-12                   417ms ± 5%     391ms ± 1%  -6.42%  (p=0.000 n=16+19)
Template-12                 61.1ms ± 1%    64.2ms ± 0%  +5.07%  (p=0.000 n=19+20)
TimeParse-12                 302ns ± 1%     305ns ± 1%  +0.90%  (p=0.000 n=18+18)
TimeFormat-12                319ns ± 1%     315ns ± 1%  -1.25%  (p=0.000 n=18+18)
[Geo mean]                  54.0µs         54.3µs       +0.58%

name         old time/op  new time/op  delta
XGarbage-12  2.24ms ± 2%  2.28ms ± 1%  +1.68%  (p=0.000 n=18+17)
XHTTP-12     11.4µs ± 1%  11.6µs ± 2%  +1.63%  (p=0.000 n=18+18)
XJSON-12     11.6ms ± 0%  12.5ms ± 0%  +7.84%  (p=0.000 n=18+17)

Updates #17503.

Change-Id: I1899f8e35662971e24bf692b517dfbe2b533c00c
Reviewed-on: https://go-review.googlesource.com/31572
Reviewed-by: Keith Randall <khr@golang.org>
2016-10-28 20:05:58 +00:00
Martin Möhrmann
b679665a18 cmd/compile: move stringtoslicebytetmp to the backend
- removes the runtime function stringtoslicebytetmp
- removes the generation of calls to stringtoslicebytetmp from the frontend
- adds handling of OSTRARRAYBYTETMP in the backend

This reduces binary sizes and avoids function call overhead.

Change-Id: Ib9988d48549cee663b685b4897a483f94727b940
Reviewed-on: https://go-review.googlesource.com/32158
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
Run-TryBot: Martin Möhrmann <martisch@uos.de>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-10-28 07:58:47 +00:00
Keith Randall
deb4177cf0 cmd/compile: use masks instead of branches for slicing
When we do

  var x []byte = ...
  y := x[i:]

We can't just use y.ptr = x.ptr + i, as the new pointer may point to the
next object in memory after the backing array.
We used to fix this by doing:

  y.cap = x.cap - i
  delta := i
  if y.cap == 0 {
    delta = 0
  }
  y.ptr = x.ptr + delta

That generates a branch in what is otherwise straight-line code.

Better to do:

  y.cap = x.cap - i
  mask := (y.cap - 1) >> 63 // -1 if y.cap==0, 0 otherwise
  y.ptr = x.ptr + i &^ mask

It's about the same number of instructions (~4, depending on what
parts are constant, and the target architecture), but it is all
inline. It plays nicely with CSE, and the mask can be computed
in parallel with the index (in cases where a multiply is required).

It is a minor win in both speed and space.

Change-Id: Ied60465a0b8abb683c02208402e5bb7ac0e8370f
Reviewed-on: https://go-review.googlesource.com/32022
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2016-10-27 20:22:49 +00:00
Robert Griesemer
50f66fbb66 cmd/compile: disallow "init" as alias
Fixes #17637.

Change-Id: I5af63b8277c0a0f9fef4880992bcb925ca088687
Reviewed-on: https://go-review.googlesource.com/32106
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2016-10-27 20:01:20 +00:00
Robert Griesemer
03d81b5ed9 cmd/compile: import/export of alias declarations
This CL completes support for alias declarations in the compiler.

Also:
- increased export format version
- updated various comments

For #16339.
Fixes #17487.

Change-Id: Ic6945fc44c0041771eaf9dcfe973f601d14de069
Reviewed-on: https://go-review.googlesource.com/32090
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2016-10-27 17:44:45 +00:00
Keith Randall
a047b6bf7d cmd/compile: emit assignments after calls in the right order
Fixes a bug where assignments that should come after a call
were instead being issued before the call.

Fixes #17596
Fixes #17618

Change-Id: Ic9ae4c34ae38fc4ccd0604b65345b05896a2c295
Reviewed-on: https://go-review.googlesource.com/32226
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
2016-10-27 16:52:30 +00:00
David Chase
bea5252a13 cmd/compile: add explicit 'where' to EscStep data for explanations
Sometimes neither the src nor the dst of an escape edge
contains the line number appropriate to the edge, so add
a field so that can be set correctly.

Also updated some of the explanations to be less jargon-y
and perhaps more informative, and folded bug example into
test.

Cleaned up some of the function/method names in esc.go
and did a quick sanity check that each "bundling" function
was actually called often enough to justify its existence.

Fixes #17459.

Change-Id: Ieba53ab0a6ba1f7a6c4962bc0b702ede9cc3a3cc
Reviewed-on: https://go-review.googlesource.com/31660
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2016-10-26 18:46:59 +00:00
Matthew Dempsky
adda7ad295 cmd/compile/internal/gc: enable new parser by default
Change-Id: I3c784986755cfbbe1b8eb8da4d64227bd109a3b0
Reviewed-on: https://go-review.googlesource.com/27203
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
2016-10-25 22:28:40 +00:00
Cherry Zhang
f6aec889e1 cmd/compile: add a writebarrier phase in SSA
When the compiler insert write barriers, the frontend makes
conservative decisions at an early stage. This may have false
positives which result in write barriers for stack writes.

A new phase, writebarrier, is added to the SSA backend, to delay
the decision and eliminate false positives. The frontend still
makes conservative decisions. When building SSA, instead of
emitting runtime calls directly, it emits WB ops (StoreWB,
MoveWB, etc.), which will be expanded to branches and runtime
calls in writebarrier phase. Writes to static locations on stack
are detected and write barriers are removed.

All write barriers of stack writes found by the script from
issue #17330 are eliminated (except two false positives).

Fixes #17330.

Change-Id: I9bd66333da9d0ceb64dcaa3c6f33502798d1a0f8
Reviewed-on: https://go-review.googlesource.com/31131
Reviewed-by: Austin Clements <austin@google.com>
Reviewed-by: David Chase <drchase@google.com>
Reviewed-by: Keith Randall <khr@golang.org>
2016-10-25 21:53:40 +00:00
Cherry Zhang
698bfa17a8 cmd/internal/obj: save link register in leaf function with non-empty frame on PPC64, ARM64, S390X
The runtime traceback code assumes non-empty frame has link
link register saved on LR architectures. Make sure it is so in
the assember.

Also make sure that LR is stored before update SP, so the traceback
code will not see a half-updated stack frame if a signal comes
during the execution of function prologue.

Fixes #17381.

Change-Id: I668b04501999b7f9b080275a2d1f8a57029cbbb3
Reviewed-on: https://go-review.googlesource.com/31760
Reviewed-by: Michael Munday <munday@ca.ibm.com>
2016-10-25 21:44:32 +00:00
David Chase
1986a450dd cmd/compile: added test to ensure that accidental fix remains
Bug 15141 was apparently fixed by some other change to the
compiler (this is plausible, it was a weird bug dependent
on a particular way of returning a large named array result),
add the test to ensure that it stays fixed.

Updates #15141.

Change-Id: I3d6937556413fab1af31c5a1940e6931563ce2f3
Reviewed-on: https://go-review.googlesource.com/31972
Run-TryBot: David Chase <drchase@google.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-10-25 15:29:27 +00:00
Robert Griesemer
1b0cf430dd cmd/compile: implement package-level aliases (no export yet)
Requires -newparser=1.

For #17487.
For #16339.

Change-Id: I156fb0c0f8a97e8c72dbbfbd7fe821efee12b957
Reviewed-on: https://go-review.googlesource.com/31597
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2016-10-25 00:54:09 +00:00
Josh Bleecher Snyder
7e9f420ddf test: delete bugs directory
It appears to be a vestigial holding ground for bugs.
But we have an issue tracker, and #1909 is there and open.

Change-Id: I912ff222a24c51fab483be0c67dad534f5a84488
Reviewed-on: https://go-review.googlesource.com/31859
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2016-10-25 00:17:57 +00:00
Josh Bleecher Snyder
93bca632d9 cmd/compile: preserve type information in inrange
Fixes #17551.

Change-Id: I84b7d82654cda3559c119aa56b07f30d0d224865
Reviewed-on: https://go-review.googlesource.com/31857
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2016-10-24 22:57:21 +00:00
Matthew Dempsky
6eede325ab cmd/compile: fix detection of duplicate cases for integer ranges
Previously, the check to make sure we only considered constant cases
for duplicates was skipping past integer ranges, because those use
n.List instead of n.Left. Thanks to Emmanuel Odeke for investigating
and helping to identify the root cause.

Fixes #17517.

Change-Id: I46fcda8ed9c346ff3a9647d50b83f1555587b740
Reviewed-on: https://go-review.googlesource.com/31716
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Emmanuel Odeke <emm.odeke@gmail.com>
Reviewed-by: Robert Griesemer <gri@golang.org>
2016-10-21 22:55:28 +00:00
Matthew Dempsky
2827923800 cmd/compile: prevent ICE from misuse of [...]T arrays
Fixes #16428.

Change-Id: I78d37472e228402bb3c06d7ebd441952386fa38a
Reviewed-on: https://go-review.googlesource.com/31731
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
2016-10-21 22:41:56 +00:00
David Chase
0f29942489 cmd/compile: Repurpose old sliceopt.go for prove phase.
Adapt old test for prove's bounds check elimination.
Added missing rule to generic rules that lead to differences
between 32 and 64 bit platforms on sliceopt test.
Added debugging to prove.go that was helpful-to-necessary to
discover that missing rule.
Lowered debugging level on prove.go from 3 to 1; no idea
why it was previously 3.

Change-Id: I09de206aeb2fced9f2796efe2bfd4a59927eda0c
Reviewed-on: https://go-review.googlesource.com/23290
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2016-10-20 23:50:19 +00:00
Matthew Dempsky
3f2cb493e5 cmd/compile: handle unsafe builtins like universal builtins
Reuse the same mechanisms for handling universal builtins like len to
handle unsafe.Sizeof, etc. Allows us to drop package unsafe's export
data, and simplifies some code.

Updates #17508.

Change-Id: I620e0617c24e57e8a2d7cccd0e2de34608779656
Reviewed-on: https://go-review.googlesource.com/31433
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
2016-10-18 22:34:44 +00:00
Dhananjay Nakrani
8b3194ac8f cmd/compile: fix code duplication in race-instrumentation
instrumentnode() accidentally copies parent's already-instrumented nodes
into child's Ninit block. This generates repeated code in race-instrumentation.
This case surfaces only when it duplicates inline-labels, because of
compile time error. In other cases, it silently generates incorrect
instrumented code. This change prevents it from doing so.

Fixes #17449.

Change-Id: Icddf2198990442166307e176b7e20aa0cf6c171c
Reviewed-on: https://go-review.googlesource.com/31317
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-10-18 20:11:01 +00:00
Russ Cox
57666c3fe8 test: avoid matching file names in errcheck
Fixes #17030.

Change-Id: Ic7f237ac7553ae0176929056e64b01667ed59066
Reviewed-on: https://go-review.googlesource.com/31351
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2016-10-18 05:32:37 +00:00
Austin Clements
d5bd797ee5 runtime: fix getArgInfo for deferred reflection calls
getArgInfo for reflect.makeFuncStub and reflect.methodValueCall is
necessarily special. These have dynamically determined argument maps
that are stored in their context (that is, their *funcval). These
functions are written to store this context at 0(SP) when called, and
getArgInfo retrieves it from there.

This technique works if getArgInfo is passed an active call frame for
one of these functions. However, getArgInfo is also used in
tracebackdefers, where the "call" is not a true call with an active
stack frame, but a deferred call. In this situation, getArgInfo
currently crashes because tracebackdefers passes a frame with sp set
to 0. However, the entire approach used by getArgInfo is flawed in
this situation because the wrapper has not actually executed, and
hence hasn't saved this metadata to any stack frame.

In the defer case, we know the *funcval from the _defer itself, so we
can fix this by teaching getArgInfo to use the *funcval context
directly when its available, and otherwise get it from the active call
frame.

While we're here, this commit simplifies getArgInfo a bit by making it
play more nicely with the type system. Rather than decoding the
*reflect.methodValue that is the wrapper's context as a *[2]uintptr,
just write out a copy of the reflect.methodValue type in the runtime.

Fixes #16331. Fixes #17471.

Change-Id: I81db4d985179b4a81c68c490cceeccbfc675456a
Reviewed-on: https://go-review.googlesource.com/31138
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2016-10-17 18:57:01 +00:00
Austin Clements
ad5fd2872f test: simplify fixedbugs/issue15747.go
The error check patterns in this test are more complex than necessary
because f2 gets inlined into f1. This behavior isn't important to the
test, so disable inlining of f2 and simplify the error check patterns.

Change-Id: Ia8aee92a52f9217ad71b89b2931494047e8d2185
Reviewed-on: https://go-review.googlesource.com/31132
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2016-10-15 21:27:45 +00:00
Austin Clements
77527a316b cmd/compile: add go:notinheap type pragma
This adds a //go:notinheap pragma for declarations of types that must
not be heap allocated. We ensure these rules by disallowing new(T),
make([]T), append([]T), or implicit allocation of T, by disallowing
conversions to notinheap types, and by propagating notinheap to any
struct or array that contains notinheap elements.

The utility of this pragma is that we can eliminate write barriers for
writes to pointers to go:notinheap types, since the write barrier is
guaranteed to be a no-op. This will let us mark several scheduler and
memory allocator structures as go:notinheap, which will let us
disallow write barriers in the scheduler and memory allocator much
more thoroughly and also eliminate some problematic hybrid write
barriers.

This also makes go:nowritebarrierrec and go:yeswritebarrierrec much
more powerful. Currently we use go:nowritebarrier all over the place,
but it's almost never what you actually want: when write barriers are
illegal, they're typically illegal for a whole dynamic scope. Partly
this is because go:nowritebarrier has been around longer, but it's
also because go:nowritebarrierrec couldn't be used in situations that
had no-op write barriers or where some nested scope did allow write
barriers. go:notinheap eliminates many no-op write barriers and
go:yeswritebarrierrec makes it possible to opt back in to write
barriers, so these two changes will let us use go:nowritebarrierrec
far more liberally.

This updates #13386, which is about controlling pointers from non-GC'd
memory to GC'd memory. That would require some additional pragma (or
pragmas), but could build on this pragma.

Change-Id: I6314f8f4181535dd166887c9ec239977b54940bd
Reviewed-on: https://go-review.googlesource.com/30939
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2016-10-15 17:58:14 +00:00
Austin Clements
a9e6cebde2 cmd/compile, runtime: add go:yeswritebarrierrec pragma
This pragma cancels the effect of go:nowritebarrierrec. This is useful
in the scheduler because there are places where we enter a function
without a valid P (and hence cannot have write barriers), but then
obtain a P. This allows us to annotate the function with
go:nowritebarrierrec and split out the part after we've obtained a P
into a go:yeswritebarrierrec function.

Change-Id: Ic8ce4b6d3c074a1ecd8280ad90eaf39f0ffbcc2a
Reviewed-on: https://go-review.googlesource.com/30938
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Keith Randall <khr@golang.org>
2016-10-15 17:58:11 +00:00
Anthony Canino
26c7b4fb1e cmd/compile: "abc"[1] is not an ideal constant
"abc"[1] is not like 'b', in that -"abc"[1] is uint8 math, not ideal constant math.
Delay the constantification until after ideal constant folding is over.

Fixes #11370.

Change-Id: Iba2fc00ca2455959e7bab8f4b8b4aac14b1f9858
Reviewed-on: https://go-review.googlesource.com/15740
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-10-13 17:41:04 +00:00
Keith Randall
442de98c14 cmd/compile,runtime: redo how map assignments work
To compile:
  m[k] = v
instead of:
  mapassign(maptype, m, &k, &v), do
do:
  *mapassign(maptype, m, &k) = v

mapassign returns a pointer to the value slot in the map.  It is just
like mapaccess except that it will allocate a new slot if k is not
already present in the map.

This makes map accesses faster but potentially larger (codewise).

It is faster because the write into the map is done when the compiler
knows the concrete type, so it can be done with a few store
instructions instead of calling typedmemmove.  We also potentially
avoid stack temporaries to hold v.

The code can be larger when the map has pointers in its value type,
since there is a write barrier call in addition to the mapassign call.
That makes the code at the callsite a bit bigger (go binary is 0.3%
bigger).

This CL is in preparation for doing operations like m[k] += v with
only a single runtime call.  That will roughly double the speed of
such operations.

Update #17133
Update #5147

Change-Id: Ia435f032090a2ed905dac9234e693972fe8c2dc5
Reviewed-on: https://go-review.googlesource.com/30815
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-10-12 20:41:23 +00:00
Alan Donovan
41a005d458 test: add test for issue 17039
Change-Id: Ieb3d605f03a7185a707621bef7160090c9bdb51f
Reviewed-on: https://go-review.googlesource.com/28873
Reviewed-by: Alan Donovan <adonovan@google.com>
2016-10-12 14:57:26 +00:00
David Chase
f1eed92fd0 cmd/compile: escape analysis needs to run "flood" to fixed point
In some cases the members of the root set from which flood
runs themselves escape, without their referents being also
tagged as escaping.  Fix this by reflooding from those roots
whose escape increases, and also enhance the "leak" test to
include reachability from a heap-escaped root.

Fixes #17318.

Change-Id: Ied1e75cee17ede8ca72a8b9302ce8201641ec593
Reviewed-on: https://go-review.googlesource.com/30693
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2016-10-11 16:32:15 +00:00
Tal Shprecher
672e579444 cmd/compile: avoid leak of dottype expression on double assignment form
This is a followup to issue #13805. That change avoid leaks for types that
don't have any pointers for the single assignment form of a dottype expression.
This does the same for the double assignment form.

Fixes #15796

Change-Id: I27474cade0ff1f3025cb6392f47b87b33542bc0f
Reviewed-on: https://go-review.googlesource.com/24906
Run-TryBot: Michael Matloob <matloob@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
2016-10-10 12:09:16 +00:00
Wedson Almeida Filho
13c829e5f6 cmd/internal/obj/x86: On amd64, relocation type for and indirect call is pc-relative.
With this change, the code in bug #15609 compiles and runs properly:

0000000000401070 <main.jump>:
  401070:	ff 15 aa 7e 06 00    	callq  *0x67eaa(%rip)        # 468f20 <main.pointer>
  401076:	c3                   	retq

0000000000468f20 g     O .rodata	0000000000000008 main.pointer

Fixes #15609

Change-Id: Iebb4d5a9f9fff335b693f4efcc97882fe04eefd7
Reviewed-on: https://go-review.googlesource.com/22950
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
2016-10-09 19:50:09 +00:00
Keith Randall
f8a0c15e90 test: re-enable live2 test on amd64
Not sure why it was ever disabled (early SSA work?) but it passes now.

Change-Id: I76439cacdbd286ce077f7e08c4d0663396a0cd8f
Reviewed-on: https://go-review.googlesource.com/30672
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-10-07 17:34:02 +00:00
David Chase
c79ba22ece test: delete sliceopt.go
It tests the behavior of the old deleted compiler.

Fixes #17362.

Change-Id: Ia2fdec734c5cbe724a9de562ed71598f67244ab3
Reviewed-on: https://go-review.googlesource.com/30593
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2016-10-06 18:19:28 +00:00
Robert Griesemer
936ae27b9c cmd/compile: untyped arrays bounds representable as integers are valid
Fixes #13485.

Change-Id: I11dd15c7d14fc19d42a3b48427a4cc1208b18e6a
Reviewed-on: https://go-review.googlesource.com/30456
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2016-10-05 22:07:58 +00:00
Robert Griesemer
39055700b1 cmd/compile: ignore struct tags when converting structs
Implementation of spec change https://golang.org/cl/24190/.

For #16085.

Change-Id: Id71ef29af5031b073e8be163f578d1bb768ff97a
Reviewed-on: https://go-review.googlesource.com/30169
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2016-10-04 17:10:47 +00:00
Keith Randall
6300161d40 cmd/compile: force folding of MOVDaddr into storezero
Fold MOVDaddr ops into MOVXstorezero ops.
Also fold ADDconst into MOVDaddr so we're sure there isn't
(MOVDstorezero (ADDconst (MOVDaddr ..)))

Without this CL, we get:

v1 = MOVDaddr {s}
v2 = VARDEF {s}
v3 = MOVDstorezero v1 v2

The liveness pass thinks the MOVDaddr is a read of s, so s is
incorrectly thought to be live at the start of the function.

Fixes #17194

Change-Id: I2b4a2f13b12aa5b072941ee1c7b89f3793650cdc
Reviewed-on: https://go-review.googlesource.com/30086
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Lynn Boger <laboger@linux.vnet.ibm.com>
Reviewed-by: Michael Munday <munday@ca.ibm.com>
2016-10-04 16:10:27 +00:00
Than McIntosh
6c5e377d23 cmd/compile: relax liveness restrictions on ambiguously live
Update gc liveness to remove special conservative treatment
of ambiguously live vars, since there is no longer a need to
protect against GCDEBUG=gcdead.

Change-Id: Id6e2d03218f7d67911e8436d283005a124e6957f
Reviewed-on: https://go-review.googlesource.com/24896
Reviewed-by: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
2016-10-03 18:07:32 +00:00
Emmanuel Odeke
2d573eee8a cmd/compile: improve error message for wrong number of arguments to return
Fixes #4215.
Fixes #6750.

Improves the error message for wrong number of arguments by comparing
the signature of the return call site arguments, versus the function's
expected return arguments.

In this CL, the signature representation of:
+ ideal numbers(TIDEAL) ie float*, complex*, rune, int is
"number" instead of "untyped number".
+ idealstring is "string" instead of "untyped string".
+ idealbool is "bool" instead of "untyped bool".

However, the representation of other types remains as the compiler
would produce.

* Example 1(in the error messages, if all lines were printed):
$ cat main.go && go run main.go
package main

func foo() (int, int) {
  return 2.3
}

func foo2() {
  return int(2), 2
}

func foo3(v int) (a, b, c, d int) {
  if v >= 5 {
    return 1
  }
  return 2, 3
}

func foo4(name string) (string, int) {
  switch name {
  case "cow":
    return "moo"
  case "dog":
    return "dog", 10, true
  case "fish":
    return ""
  default:
    return "lizard", 10
  }
}

type S int
type T string
type U float64

func foo5() (S, T, U) {
  if false {
    return ""
  } else {
    ptr := new(T)
    return ptr
  }
  return new(S), 12.34, 1 + 0i, 'r', true
}

func foo6() (T, string) {
  return "T"
}

./issue4215.go:4: not enough arguments to return, got (number) want (int, int)
./issue4215.go:8: too many arguments to return, got (int, number) want ()
./issue4215.go:13: not enough arguments to return, got (number) want (int, int, int, int)
./issue4215.go:15: not enough arguments to return, got (number, number) want (int, int, int, int)
./issue4215.go:21: not enough arguments to return, got (string) want (string, int)
./issue4215.go:23: too many arguments to return, got (string, number, bool) want (string, int)
./issue4215.go:25: not enough arguments to return, got (string) want (string, int)
./issue4215.go:37: not enough arguments to return, got (string) want (S, T, U)
./issue4215.go:40: not enough arguments to return, got (*T) want (S, T, U)
./issue4215.go:42: too many arguments to return, got (*S, number, number, number, bool) want (S, T, U)
./issue4215.go:46: not enough arguments to return, got (string) want (T, string)
./issue4215.go:46: too many errors

* Example 2:
$ cat 6750.go && go run 6750.go
package main

import "fmt"

func printmany(nums ...int) {
  for i, n := range nums {
    fmt.Printf("%d: %d\n", i, n)
  }
  fmt.Printf("\n")
}

func main() {
  printmany(1, 2, 3)
  printmany([]int{1, 2, 3}...)
  printmany(1, "abc", []int{2, 3}...)
}
./issue6750.go:15: too many arguments in call to printmany, got (number, string, []int) want (...int)

Change-Id: I6fdce78553ae81770840070e2c975d3e3c83d5d8
Reviewed-on: https://go-review.googlesource.com/25156
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2016-10-02 16:28:02 +00:00
Matthew Dempsky
03a1dc3522 cmd/compile: don't crash on (unsafe.Sizeof)(0)
Fixes #17270.

Change-Id: I4affa57e10baf1a758bc0977265d160f220b2945
Reviewed-on: https://go-review.googlesource.com/29960
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-09-28 23:13:53 +00:00
Cherry Zhang
4d07d3e29c cmd/compile: re-enable nilcheck removal for newobject
Also add compiler debug ouput and add a test.

Fixes #15390.

Change-Id: Iceba1414c29bcc213b87837387bf8ded1f3157f1
Reviewed-on: https://go-review.googlesource.com/30011
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2016-09-28 19:41:49 +00:00
Keith Randall
98938189a1 cmd/compile: remove duplicate nilchecks
Mark nil check operations as faulting if their arg is zero.
This lets the late nilcheck pass remove duplicates.

Fixes #17242.

Change-Id: I4c9938d8a5a1e43edd85b4a66f0b34004860bcd9
Reviewed-on: https://go-review.googlesource.com/29952
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2016-09-27 23:54:01 +00:00
Alberto Donizetti
7f1bc53379 cmd/compile: only allow integer expressions as keys in array literals
Fixes #16439
Updates #16679

Change-Id: Idff4b313f29351866b1a649786501adee85fd580
Reviewed-on: https://go-review.googlesource.com/29011
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>
2016-09-26 17:49:41 +00:00
Alberto Donizetti
375092bdcb cmd/compile: fix bogus "fallthrough statement out of place"
When processing a fallthrough, the casebody function in swt.go
checks that the last statement has indeed Op == OXFALL (not-processed
fallthrough) before setting it to OFALL (processed fallthrough).

Unfortunately, sometimes the fallthrough statement won't be in the
last node. For example, in

case 0:
	 return func() int {return 1}()
	 fallthrough

the compiler generates

autotmp_0 = (func literal)(); return autotmp_0; fallthrough; <node VARKILL>

with an OVARKILL node in the last position. casebody will find that
last.Op != OXFALL, won't mark the fallthrough as processed, and the
fallthrough line will cause a "fallthrough statement out of place" error.

To fix this, we change casebody so that it searches for the fallthrough
statement backwards in the statements list, without assuming that it'll
be in the last position.

Fixes #13262

Change-Id: I366c6caa7fd7442d365bd7a08cc66a552212d9b2
Reviewed-on: https://go-review.googlesource.com/22921
Run-TryBot: Quentin Smith <quentin@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Quentin Smith <quentin@golang.org>
2016-09-26 15:46:44 +00:00
Cherry Zhang
d586aae1f4 test: errorcheck auto-generated functions
Add an "errorcheckwithauto" action which performs error check
including lines with auto-generated functions (excluded by
default). Comment "// ERRORAUTO" matches these lines.

Add testcase for CL 29570 (as an example).

Updates #16016, #17186.

Change-Id: Iaba3727336cd602f3dda6b9e5f97dafe0848e632
Reviewed-on: https://go-review.googlesource.com/29652
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2016-09-22 20:10:30 +00:00
Michael Munday
e94c52933b cmd/compile: intrinsify Ctz{32,64} and Bswap{32,64} on s390x
Also adds the 'find leftmost one' instruction (FLOGR) and replaces the
WORD-encoded use of FLOGR in math/big with it.

Change-Id: I18e7cd19e75b8501a6ae8bd925471f7e37ded206
Reviewed-on: https://go-review.googlesource.com/29372
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Michael Munday <munday@ca.ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-09-19 19:03:01 +00:00
Keith Randall
ca4089ad62 cmd/compile: args no longer live until end-of-function
We're dropping this behavior in favor of runtime.KeepAlive.
Implement runtime.KeepAlive as an intrinsic.

Update #15843

Change-Id: Ib60225bd30d6770ece1c3c7d1339a06aa25b1cbc
Reviewed-on: https://go-review.googlesource.com/28310
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
2016-09-19 16:54:35 +00:00
Keith Randall
6129f37367 cmd/compile: inline convT2{I,E} when result doesn't escape
No point in calling a function when we can build the interface
using a known type (or itab) and the address of a local.

Get rid of third arg (preallocated stack space) to convT2{I,E}.

Makes go binary smaller by 0.2%

benchmark                   old ns/op     new ns/op     delta
BenchmarkEfaceInteger-8     16.7          10.1          -39.52%

Update #17118
Update #15375

Change-Id: I9724a1f802bfa1e3957bf1856b55558278e198a2
Reviewed-on: https://go-review.googlesource.com/29373
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2016-09-19 02:37:08 +00:00
Trey Lawrence
fc5df089da cmd/compile: fix compiler bug for constant equality comparison
The compiler incorrectly will error when comparing a nil pointer
interface to a nil pointer of any other type. Example:
(*int)(nil) == interface{}(nil)
Will error with "gc: illegal constant expression: *int == interface {}"

Fixes #16702

Change-Id: I1a15d651df2cfca6762b1783a28b377b2e6ff8c6
Reviewed-on: https://go-review.googlesource.com/27591
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2016-09-17 01:12:24 +00:00
Keith Randall
c199c76cb4 cmd/compile: turn live variable test off for ppc
ppc64 has an extraneous variable live in some situations.
We need a better tighten pass to get rid of this extra variable.
I'm working on it, but fix the test in the meantime.

Fixes build for ppc64.

Change-Id: I1efb9ccb234a64f2a1c228abd2b3195f67fbeb41
Reviewed-on: https://go-review.googlesource.com/29353
Reviewed-by: David Chase <drchase@google.com>
2016-09-16 19:41:42 +00:00
Keith Randall
b265d51789 test,cmd/compile: remove _ssa file suffix
Everything is SSA now.

Update #16357

Change-Id: I436dbe367b863ee81a3695a7d653ba4bfc5b0f6c
Reviewed-on: https://go-review.googlesource.com/29232
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-09-15 20:47:01 +00:00
Keith Randall
f13701bf2f test: make SSA tests unconditional
Delete legacy backend tests, make SSA tests unconditional.

Next CL will remove _ssa from the file names.

Update #16357

Change-Id: I2a7f5dcbc69455f63b5e6e6b2725df26ab86c8dd
Reviewed-on: https://go-review.googlesource.com/29231
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-09-15 20:21:26 +00:00
Josh Bleecher Snyder
c9fd997524 cmd/compile: unroll comparisons to short constant strings
Unroll s == "ab" to

len(s) == 2 && s[0] == 'a' && s[1] == 'b'

This generates faster and shorter code
by avoiding a runtime call.
Do something similar for !=.

The cutoff length is 6. This was chosen empirically
by examining binary sizes on arm, arm64, 386, and amd64
using the SSA backend.

For all architectures examined, 4, 5, and 6 were
the ideal cutoff, with identical binary sizes.

The distribution of constant string equality sizes
during 'go build -a std' is:

 40.81%   622 len 0
 14.11%   215 len 4
  9.45%   144 len 1
  7.81%   119 len 3
  7.48%   114 len 5
  5.12%    78 len 7
  4.13%    63 len 2
  3.54%    54 len 8
  2.69%    41 len 6
  1.18%    18 len 10
  0.85%    13 len 9
  0.66%    10 len 14
  0.59%     9 len 17
  0.46%     7 len 11
  0.26%     4 len 12
  0.20%     3 len 19
  0.13%     2 len 13
  0.13%     2 len 15
  0.13%     2 len 16
  0.07%     1 len 20
  0.07%     1 len 23
  0.07%     1 len 33
  0.07%     1 len 36

A cutoff of length 6 covers most of the cases.

Benchmarks on amd64 comparing a string to a constant of length 3:

Cmp/1same-8           4.78ns ± 6%  0.94ns ± 9%  -80.26%  (p=0.000 n=20+20)
Cmp/1diffbytes-8      6.43ns ± 6%  0.96ns ±11%  -85.13%  (p=0.000 n=20+20)
Cmp/3same-8           4.71ns ± 5%  1.28ns ± 5%  -72.90%  (p=0.000 n=20+20)
Cmp/3difffirstbyte-8  6.33ns ± 7%  1.27ns ± 7%  -79.90%  (p=0.000 n=20+20)
Cmp/3difflastbyte-8   6.34ns ± 8%  1.26ns ± 9%  -80.13%  (p=0.000 n=20+20)

The change to the prove test preserves the
existing intent of the test. When the string was
short, there was a new "proved in bounds" report
that referred to individual byte comparisons.

Change-Id: I593ac303b0d11f275672090c5c786ea0c6b8da13
Reviewed-on: https://go-review.googlesource.com/26758
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2016-09-15 15:37:00 +00:00
Josh Bleecher Snyder
df2b63f09b cmd/compile: unwrap fewer CONVNOPs in staticassign
staticassign unwraps all CONVNOPs.
However, in the included test, we need the
CONVNOP for everything to typecheck.
Stop unwrapping unnecessarily.

The code we generate for this example is
suboptimal, but that's not new; see #17113.

Fixes #17111.

Change-Id: I29532787a074a6fe19a5cc53271eb9c84bf1b576
Reviewed-on: https://go-review.googlesource.com/29213
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
2016-09-15 14:08:10 +00:00
Keith Randall
3134ab3c2d cmd/compile: redo nil checks
Get rid of BlockCheck. Josh goaded me into it, and I went
down a rabbithole making it happen.

NilCheck now panics if the pointer is nil and returns void, as before.
BlockCheck is gone, and NilCheck is no longer a Control value for
any block. It just exists (and deadcode knows not to throw it away).

I rewrote the nilcheckelim pass to handle this case.  In particular,
there can now be multiple NilCheck ops per block.

I moved all of the arch-dependent nil check elimination done as
part of ssaGenValue into its own proper pass, so we don't have to
duplicate that code for every architecture.

Making the arch-dependent nil check its own pass means I needed
to add a bunch of flags to the opcode table so I could write
the code without arch-dependent ops everywhere.

Change-Id: I419f891ac9b0de313033ff09115c374163416a9f
Reviewed-on: https://go-review.googlesource.com/29120
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
2016-09-15 02:42:13 +00:00
Matthew Dempsky
fb273fc3a3 cmd/compile: fix comma-ok assignments for non-boolean ok
Passes toolstash -cmp.

Fixes #16870.

Change-Id: I70dc3bbb3cd3031826e5a54b96ba1ea603c282d1
Reviewed-on: https://go-review.googlesource.com/27910
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
2016-09-14 22:11:38 +00:00
Jan Mercl
2e675142dd test/float_lit2: fix expressions in comment
The change corrects the values of the largest float32 value (f1) and the
value of the halfway point between f1 and the next, overflow value (f2).

Fixes #17012

Change-Id: Idaf9997b69d61fafbffdb980d751c9857732e14d
Reviewed-on: https://go-review.googlesource.com/29171
Reviewed-by: Robert Griesemer <gri@golang.org>
2016-09-14 16:39:47 +00:00
Michael Munday
7e2b5a102e test: re-enable phi optimization test
CL 28978 (6ec993a) accidentally disabled the test (it would only
run if amd64 AND s390x, whereas it should be amd64 OR s390x).

Change-Id: I23c1ad71724ff55f5808d5896b19b62c8ec5af76
Reviewed-on: https://go-review.googlesource.com/28981
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2016-09-13 20:06:13 +00:00
Michael Munday
6ec993adc3 cmd/compile: add SSA backend for s390x and enable by default
The new SSA backend modifies the ABI slightly: R0 is now a usable
general purpose register.

Fixes #16677.

Change-Id: I367435ce921e0c7e79e021c80cf8ef5d1d1466cf
Reviewed-on: https://go-review.googlesource.com/28978
Run-TryBot: Michael Munday <munday@ca.ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2016-09-13 19:39:38 +00:00
Cherry Zhang
8ff4260777 cmd/compile: intrinsify Ctz, Bswap on ARM
Atomic ops on ARM are implemented with kernel calls, so they are
not intrinsified.

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

This:

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

Fixes #6289
Fixes #15528

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

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

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

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

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

Fixes #16996

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

Fixes #17005.

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

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

Updates #16010.

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

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

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

Fixes #15895

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

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

Fixes   #16940
Updates #16949

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

Fixes #16948.

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

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

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

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

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

runtime:

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

strings:

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

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

Updates #13162

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

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

godoc 386 binary shrinks by approximately 12 kilobyte.

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

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

Fixes  #15357

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

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

Fixes #16359.

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

	struct { i int }

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

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

Fixes #16616

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

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

rather than

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

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

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

Updates #15303


Sample code:

type T struct {
	a, b int8
}

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


SSA before:

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

SSA after:

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


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

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

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

Fixes #15844.
Fixes #16697.

strconv benchmarks:

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

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

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

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

Fixes #15514.

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

Fixes #16317

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

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

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

It also allows us to simplify sorting.

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

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

Negligible compilebench impact.

Fixes #15912.

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

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

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

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

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

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

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

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

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

Enhanced debugging output for shared libs test.

Rebased onto master.

Updates #16010.

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

Test copied from Keith's CL 27202.

Fixes #16741.

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

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

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

This also considerably shrinks a core fmt
routine:

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

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

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

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

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

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

Fixes #16733

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

Turn on SSA by default, also adjust tests.

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

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

Turn on SSA backend for 386 by default.

Fixes #16358

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

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

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

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

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

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

Fixes #16515.

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

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

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

Updates #15365.

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

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

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

Fixes #16035.

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

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

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

Updates #15365.

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

Fixes #16249.

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

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

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

Fixes #16189

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

Fixes #16193.

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

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

Fixes #16095.

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

Added test cases.

Fixes #16133.

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

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

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

Fixes #16130.

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

Fixes #16037

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

Fixes #16008.

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

Fixes #16016

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

Fixes #15975 (if this is the intended behavior)

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

Fixes #15988

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

Fixes #15961

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

Fixes #15926.

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

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

Fixes #15902

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

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

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

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

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

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

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

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

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

The OPARAM node type goes away too.

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

Fixes #15747.

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

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

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

Fixes #15838.

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

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

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

Fixes #14136.

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

Fixes #15733

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

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

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

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

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

Fixes #15277

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

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

would be reordered into a sequence of statements like

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

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

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

Fixes #15329.

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

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

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

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

2) add a test.

Fixes #15585.

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

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

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

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

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

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

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

Fixes #15572.

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

Fixes #15602

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

For #15602.

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

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

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

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

The test for #15548 covers also this change.

For #15548.

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

Fixes #14678

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

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

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

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

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

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

Fixes #15213

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

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

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

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

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

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

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

This very slightly improves the go1 benchmarks:

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

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

Fixes #15382

Change-Id: Ibce7b28f0586d593b33c4d4ecc5d5e7e7c905d13
Reviewed-on: https://go-review.googlesource.com/22292
Reviewed-by: Michael Munday <munday@ca.ibm.com>
Reviewed-by: David Chase <drchase@google.com>
2016-04-27 17:47:49 +00:00