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Commit Graph

2302 Commits

Author SHA1 Message Date
Robert Griesemer
a20556bf56 cmd/compile/internal/gc: correctly use internal call to error reporting
Fixes #13266.

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

TBR=rsc

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

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

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

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

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

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

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

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

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

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

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

Updates #13098.

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

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

Fixes #13098.

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

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

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

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

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

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

Fixes #13169

The original 9345:

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

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

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

Fixes #11506

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

Fixes #13160
Update #12552

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

Fixes #13171

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

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

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

Fixes #11987

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

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

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

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

Fixes #13100

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

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

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

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

Updates #13100

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

Updates #13098

Change-Id: I179ed810b49bbb96c8df462bfa20b70231b26772
Reviewed-on: https://go-review.googlesource.com/16521
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2015-10-30 20:48:03 +00:00
Todd Neal
a92543e1a1 cmd/compile: add support for a go:noinline directive
Some tests need to disable inlining of a function.  It's currently done
in one of a few ways (adding a function call, an empty switch, or a
defer).  Add support for a less fragile 'go:noinline' directive that
prevents inlining.

Fixes #12312

Change-Id: Ife444e13361b4a927709d81aa41e448f32eec8d4
Reviewed-on: https://go-review.googlesource.com/13911
Run-TryBot: Todd Neal <todd@tneal.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
2015-10-29 23:16:27 +00:00
acanino
b60c8203ea cmd/compile: "invalid variable name x in type switch", where x is a name of a constant
Small fix: looks like a short variable declaration with a type switch
checks to make sure the variable used had valid shape (ONAME, OTYPE, or
ONONAME) and rejects everything else. Then a new variable is declared.
If the symbol contained in the declaration was a named OLITERAL (still a
valid identifier obviously) it would be rejected, even though a new
variable would have been declared.

Fix adds this case to the check.

Added a test case from issue12413.

Fixes #12413

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

Change-Id: Id469cd92f5f9436b0ef948ee1a252ed1842bc7aa
Reviewed-on: https://go-review.googlesource.com/16133
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
2015-10-20 22:11:11 +00:00
Matthew Dempsky
67722fea50 cmd/compile/internal/gc: reject invalid unsafe.Sizeof([0]byte{}[0])
Apply static bounds checking logic during type checking even to
zero-element arrays, but skip synthesized OINDEX nodes that the
compiler has asserted are within bounds (such as the ones generated
while desugaring ORANGE nodes).  This matches the logic in walkexpr
that also skips static bounds checking when Bounded is true.

Passes toolstash/buildall.

Fixes #12944.

Change-Id: I14ba03d71c002bf969d69783bec8d1a8e10e7d75
Reviewed-on: https://go-review.googlesource.com/15902
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2015-10-15 20:56:58 +00:00
Didier Spezia
cb0e98b833 cmd/compile: fix some C to Go translation leftovers
Following the C to Go translation, some useless variables
were left in the code. In fmt.go, this was harmless.
In lex.go, it broke the error message related to
non-canonical import paths.

Fix it, and remove the useless variables.

The added test case is ignored in the go/types tests, since
the behavior of the non-canonical import path check seems
to be different.

Fixes #11362

Change-Id: Ic9129139ede90357dc79ebf167af638cf44536fa
Reviewed-on: https://go-review.googlesource.com/15580
Reviewed-by: Marvin Stenger <marvin.stenger94@gmail.com>
Reviewed-by: Minux Ma <minux@golang.org>
Run-TryBot: Minux Ma <minux@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2015-10-08 01:51:24 +00:00
Ian Lance Taylor
449cc06e98 test: adjust gccgo expected import errors
Update two tests for the recently submitted gccgo change
https://golang.org/cl/14259.

Change-Id: Ib18bc87ea512074aa91fd4096d0874b72e2243e5
Reviewed-on: https://go-review.googlesource.com/15493
Reviewed-by: Chris Manghane <cmang@golang.org>
2015-10-07 14:37:44 +00:00
Shenghou Ma
48b1e6bc97 test: gofmt fixedbugs/issue10975.go
Change-Id: I772d1bc3e394cdd707f210f2aaff77100d299e24
Reviewed-on: https://go-review.googlesource.com/15380
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2015-10-06 06:56:11 +00:00
Michael Hudson-Doyle
710b9ad617 cmd/compile/internal/ppc64: fix the epilogue for non-leaf generated methods
This lets us re-enable duffzero.

Fixes #12108

Change-Id: Iefd24d26eaa56067caa2c29ff99cd20a42d8714a
Reviewed-on: https://go-review.googlesource.com/14937
Reviewed-by: Keith Randall <khr@golang.org>
2015-10-06 03:34:13 +00:00
Raul Silvera
27ee719fb3 pprof: improve sampling for heap profiling
The current heap sampling introduces some bias that interferes
with unsampling, producing unexpected heap profiles.
The solution is to use a Poisson process to generate the
sampling points, using the formulas described at
https://en.wikipedia.org/wiki/Poisson_process

This fixes #12620

Change-Id: If2400809ed3c41de504dd6cff06be14e476ff96c
Reviewed-on: https://go-review.googlesource.com/14590
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Minux Ma <minux@golang.org>
Run-TryBot: Minux Ma <minux@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2015-10-05 08:15:09 +00:00
David Chase
f7a39a54e9 cmd/compile: escape analysis, don't always escape variadic args
Turns out the summary information for the ... args was
already correctly computed, all that lacked was to make
use of it and correct tests that documented our prior
deficiencies.

Fixes #12006

Change-Id: Ie8adfab7547f179391d470679598f0904aabf9f7
Reviewed-on: https://go-review.googlesource.com/15200
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
2015-10-04 20:45:35 +00:00
acanino
acc90c53e8 cmd/compile: Fix internal compiler: getinarg: not a func when returning invalid interface.
Internal error arose from calling methodfunc on a invalid interface
field during the implements check. int obviously isn't a function,
and errors on getinarg...

for im := iface.Type; im != nil; im = im.Down {
  imtype = methodfunc(im.Type, nil)
  // ...
}

Fix handles the internal compiler error, but does not throw an
additional error, i.e. the following code will error on the I
interface, but type A will pass the implements check since
'Read(string) string' is implemented and 'int' is skipped

type I interface {
  Read(string) string
  int
}

type A struct {
}

func (a *A) Read(s string) string {
  return s
}

func New() I {
  return new(A)
}

Fixes #10975

Change-Id: I4b54013afb2814db3f315515f0c742d8631ca500
Reviewed-on: https://go-review.googlesource.com/13747
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2015-10-03 15:32:46 +00:00
David Chase
745cdc3ad7 cmd/compile: repair escape analysis of range &fixedArray
The existing test did not take into account the implicit
dereference of &fixedArray and thus heap-escaped when it
was not necessary.

Also added a detailed test for this and related cases.

Fixes #12588

Change-Id: I951e9684a093082ccdca47710f69f4366bd6b3cf
Reviewed-on: https://go-review.googlesource.com/15130
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
2015-10-01 18:49:18 +00:00
Joel Sing
82a9d90eda tests/fixedbugs: make test for issue11656 run known instruction
As detailed in #11910, the current implementation attempts to execute an area
of memory with unknown content. If the memory is executable, the result is
unpredictable - instead, make the test deterministic by attempting to execute
an instruction that is known to trigger a trap on the given architecture.

The new implementation is written by iant@ and provided via #11910.

Update issue #11910

Change-Id: Ia698c36e0dd98a9d9d16a701f60f6748c6faf896
Reviewed-on: https://go-review.googlesource.com/15058
Run-TryBot: Joel Sing <jsing@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2015-09-28 04:23:33 +00:00
Robert Griesemer
7b7f85534c test/fixedbugs: update overly restrictive test case
See discussion in https://go-review.googlesource.com/14830 .

Change-Id: I94f25f92b8cdaa509d2c335865a645228425804d
Reviewed-on: https://go-review.googlesource.com/14837
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2015-09-22 17:54:01 +00:00
Robert Griesemer
c396c047c6 src/cmd/compile/internal/gc: remove now unnecessary restriction on float exponent parsing
https://go-review.googlesource.com/#/c/13778/ fixed this issue in math/big.
Remove restriction in compiler.

Fixes #11326.

Change-Id: I1429d0dd0d79431706c65616413373fff58f081e
Reviewed-on: https://go-review.googlesource.com/14830
Reviewed-by: Rob Pike <r@golang.org>
2015-09-22 00:22:49 +00:00
Michael Hudson-Doyle
955b4caa48 test: move allocation before munmap in recover4
recover4 allocates 16 pages of memory via mmap, makes a 4 page hole in it with
munmap, allocates another 16 pages of memory via normal allocation and then
tries to copy from one to the other. For some reason on arm64 (but no other
platform I have tested) the second allocation sometimes causes the runtime to
ask the kernel for 4 additional pages of memory -- which the kernel satisfies
by remapping the pages that were just unmapped!

Moving the second allocation before the munmap fixes this behaviour, I can run
recover4 tens of thousands of times without failure with this fix vs a failure
rate of ~0.5% before.

Fixes #12549

Change-Id: I490b895b606897e4f7f25b1b51f5d485a366fffb
Reviewed-on: https://go-review.googlesource.com/14632
Reviewed-by: Dave Cheney <dave@cheney.net>
2015-09-16 08:51:48 +00:00
Dave Cheney
dab0dac01a cmd/compile: convert typecheck_stack to []*Node
This one of a set of changes to make the transition away from NodeList
easier by removing cases in which NodeList doesn't act semi-trivially like a
[]*Node.

This CL was originally prepared by Josh Bleecher Snyder <josharian@gmail.com>.

This change passes go build -toolexec 'toolstash -cmp' -a std.

Change-Id: I4d041b343952f4a31f3150fd70669e08fcaa74f8
Reviewed-on: https://go-review.googlesource.com/14305
Run-TryBot: Dave Cheney <dave@cheney.net>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2015-09-06 23:50:51 +00:00
Dave Cheney
703bd83623 cmd/compile: use []*Node instead of NodeList in sinit
This is a first of a set of changes to make the transition away from NodeList
easier by removing cases in which NodeList doesn't act semi-trivially like a
[]*Node.

This CL was originally prepared by Josh Bleecher Snyder <josharian@gmail.com>.

This change passes go build -toolexec 'toolstash -cmp' -a std.

Change-Id: Iad10b75e42b5b24e1694407841282fa3bab2dc9f
Reviewed-on: https://go-review.googlesource.com/14232
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2015-09-05 02:25:01 +00:00
Ulrich Kunitz
6ec1809b83 cmd/compile: fix register allocation for == operator
The issue 12226 has been caused by the allocation of the same register
for the equality check of two byte values. The code in cgen.go freed the
register for the second operand before the allocation of the register
for the first operand.

Fixes #12226

Change-Id: Ie4dc33a488bd48a17f8ae9b497fd63c1ae390555
Reviewed-on: https://go-review.googlesource.com/13771
Reviewed-by: Russ Cox <rsc@golang.org>
2015-08-25 18:10:14 +00:00
Alberto Donizetti
85de30e72f cmd/compile: allow huge rsh in constants arithmetic
Currently an expression like

var v = 0 >> 1000

is rejected by gc with a "stupid shift" error, while gotype
compiles it successfully.

As suggested by gri on the issue tracker, allow an rsh right
operand to be any valid uint value.

Fixes #11328

Change-Id: I6ccb3b7f842338d91fd26ae37dd4fa279d7fc440
Reviewed-on: https://go-review.googlesource.com/13777
Reviewed-by: Robert Griesemer <gri@golang.org>
2015-08-21 20:27:22 +00:00
Keith Randall
e97ab0a0ac cmd/compile: remove stale register use array
The reg[] array in .../gc is where truth lies.  The copy in .../ARCH
is incorrect as it is mostly not updated to reflect regalloc decisions.

This bug was introduced in the rewrite
https://go-review.googlesource.com/#/c/7853/.  The new reg[] array was
introduced in .../gc but not all of the uses were removed in the
.../ARCH directories.

Fixes #12133

Change-Id: I6364fc403cdab92d802d17f2913ba1607734037c
Reviewed-on: https://go-review.googlesource.com/13630
Reviewed-by: Russ Cox <rsc@golang.org>
2015-08-15 17:37:14 +00:00
Mikio Hara
fd179afb56 test/bench/shootout: fix build
Change-Id: Ic8ff6c28ec899cf5e01553b83110eb6262870995
Reviewed-on: https://go-review.googlesource.com/12918
Reviewed-by: Russ Cox <rsc@golang.org>
2015-07-31 17:37:58 +00:00
Andrew Gerrand
b63fb59de8 test/bench/shootout: clean up binaries after run
Update #11943

Change-Id: I3e6592876bf16d2f9129995b723ecf69c069653d
Reviewed-on: https://go-review.googlesource.com/12913
Reviewed-by: Russ Cox <rsc@golang.org>
2015-07-31 02:50:43 +00:00
David Chase
6f6bcadc17 cmd/compile: add case for ODOTTYPE to escwalk
ODOTTYPE should be treated a whole lot like ODOT,
but it was missing completely from the switch in
escwalk and thus escape status did not propagate
to fields.

Since interfaces are required to trigger this bug,
the test was added to escape_iface.go.

Fixes #11931.

Change-Id: Id0383981cc4b1a160f6ad447192a112eed084538
Reviewed-on: https://go-review.googlesource.com/12921
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Reviewed-by: Russ Cox <rsc@golang.org>
2015-07-30 17:39:44 +00:00
Russ Cox
b2dfacf35e runtime: change arm software div/mod call sequence not to modify stack
Instead of pushing the denominator argument on the stack,
the denominator is now passed in m.

This fixes a variety of bugs related to trying to take stack traces
backwards from the middle of the software div/mod routines.
Some of those bugs have been kludged around in the past,
but others have not. Instead of trying to patch up after breaking
the stack, this CL stops breaking the stack.

This is an update of https://golang.org/cl/19810043,
which was rolled back in https://golang.org/cl/20350043.

The problem in the original CL was that there were divisions
at bad times, when m was not available. These were divisions
by constant denominators, either in C code or in assembly.
The Go compiler knows how to generate division by multiplication
for constant denominators, but the C compiler did not.
There is no longer any C code, so that's taken care of.
There was one problematic DIV in runtime.usleep (assembly)
but https://golang.org/cl/12898 took care of that one.
So now this approach is safe.

Reject DIV/MOD in NOSPLIT functions to keep them from
coming back.

Fixes #6681.
Fixes #6699.
Fixes #10486.

Change-Id: I09a13c76ad08ba75b3bd5d46a3eb78e66a84ab38
Reviewed-on: https://go-review.googlesource.com/12899
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2015-07-30 16:14:05 +00:00
Russ Cox
034a10d44c cmd/internal/obj/arm64: reject misaligned stack frames, except empty frames
The layout code has to date insisted on stack frames that are 16-aligned
including the saved LR, and it ensured this by growing the frame itself.
This breaks code that refers to values near the top of the frame by positive
offset from SP, and in general it's too magical: if you see TEXT xxx, $N,
you expect that the frame size is actually N, not sometimes N and sometimes N+8.

This led to a serious bug in the compiler where ambiguously live values
were not being zeroed correctly, which in turn triggered an assertion
in the GC about finding only valid pointers. The compiler has been
fixed to always emit aligned frames, and the hand-written assembly
has also been fixed.

Now that everything is aligned, make unaligned an error instead of
something to "fix" silently.

For #9880.

Change-Id: I05f01a9df174d64b37fa19b36a6b6c5f18d5ba2d
Reviewed-on: https://go-review.googlesource.com/12848
Reviewed-by: Austin Clements <austin@google.com>
2015-07-29 21:37:12 +00:00
David du Colombier
68117a91ae runtime: fix x86 stack trace for call to heap memory on Plan 9
Russ Cox fixed this issue for other systems
in CL 12026, but the Plan 9 part was forgotten.

Fixes #11656.

Change-Id: I91c033687987ba43d13ad8f42e3fe4c7a78e6075
Reviewed-on: https://go-review.googlesource.com/12762
Reviewed-by: Russ Cox <rsc@golang.org>
2015-07-28 19:01:41 +00:00
Ian Lance Taylor
2fc2f8ddc2 test: don't run fixedbugs/issue11656.go on netbsd/386
The netbsd/386 builder reports a failure at
http://build.golang.org/log/c21c45a4fc6f4845868aa3ebde0f5bb3f167f3a3

I'm assuming that this is similar to the unknown openbsd failure.

Update #11910.

Change-Id: I9cdfefa23dc7cda3849f14814b3ce531f1d39e93
Reviewed-on: https://go-review.googlesource.com/12777
Reviewed-by: David Crawshaw <crawshaw@golang.org>
2015-07-28 16:36:46 +00:00
Ian Lance Taylor
92e2252b21 test: don't run issue10607.go on ppc64
This is a reprise of https://golang.org/cl/12623.  In that a CL I made
a suggestion which forgot that the +build constraints in the test
directory are not the same as those supported by the go tool: in the
test directory, if a single +build line fails, the test is skipped.
(In my defense, the code I was commenting on was also wrong.)

Change-Id: I8f29392a80b1983027f9a33043c803578409d678
Reviewed-on: https://go-review.googlesource.com/12776
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2015-07-28 15:22:56 +00:00
Russ Cox
a2cf0568e8 Revert "test: do not run external linking test on ppc64le"
Broke most builders.

This reverts commit a60c5366f9.

Change-Id: Iae952cfcc73ef5da621616a0b3d586b60d1ce9c9
Reviewed-on: https://go-review.googlesource.com/12684
Reviewed-by: Russ Cox <rsc@golang.org>
2015-07-27 16:53:41 +00:00
Michael Hudson-Doyle
a60c5366f9 test: do not run external linking test on ppc64le
Change-Id: I9b8a6ac1ff6bef3b7f1e033bfd029f2a59e30297
Reviewed-on: https://go-review.googlesource.com/12623
Reviewed-by: Russ Cox <rsc@golang.org>
2015-07-27 16:22:12 +00:00
David Chase
731dcdae6d cmd/compile: prepend captured args to called-closure params
Old code appended, did not play well with a closure
with a ... param.

Fixes #11075.

Change-Id: Ib7c8590c5c4e576e798837e7499e00f3494efb4a
Reviewed-on: https://go-review.googlesource.com/12580
Reviewed-by: Russ Cox <rsc@golang.org>
Run-TryBot: David Chase <drchase@google.com>
2015-07-23 19:02:19 +00:00
David Chase
2584974d16 cmd/compile: adjust annotation of implicit operations.
Limit probe to ODOT/OIND/ODOTPTR for now; that works.

Fixes #11790

Change-Id: I411271e702c5fe6ceb880ca47c7dacc37ffcbb6a
Reviewed-on: https://go-review.googlesource.com/12532
Reviewed-by: Russ Cox <rsc@golang.org>
2015-07-23 14:19:07 +00:00
Ian Lance Taylor
e9fcd6ed2b cmd/link: if -B option was used, pass it to the external linker
Fixes #10607.

Change-Id: Ib294cf65b07103b60f62b86b21ff2d07b25136fe
Reviewed-on: https://go-review.googlesource.com/12242
Reviewed-by: Russ Cox <rsc@golang.org>
2015-07-21 03:57:55 +00:00
Ian Lance Taylor
dabb268170 cmd/compile: ignore carriage return in magic comments
Update #11771.

Change-Id: I3bb3262619765d3ca79652817e17e8f260f41907
Reviewed-on: https://go-review.googlesource.com/12379
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2015-07-18 17:33:53 +00:00
Russ Cox
19916e453e test/fixedbugs: disable issue11656.go on arm64
For #11656.

Change-Id: I8365d33a15419bd0e54f71182ad0994e41650264
Reviewed-on: https://go-review.googlesource.com/12248
Reviewed-by: Russ Cox <rsc@golang.org>
2015-07-16 02:16:20 +00:00
Ian Lance Taylor
2e4b659954 cmd/compile: recognize embedded field in inlined function
There was already special code to recognize "?" in hidden_structdcl,
which is used for inlined types and variables.  This recognizes "?" in
structdcl as well, a case that arises when a struct type appears
within an inlined function body.

Fixes #10219.

Change-Id: Ic5257ae54f817e0d4a189c2294dcd633c9f2101a
Reviewed-on: https://go-review.googlesource.com/12241
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2015-07-15 06:04:51 +00:00
Russ Cox
0bcdffeea6 runtime: fix x86 stack trace for call to heap memory
Fixes #11656.

Change-Id: Ib81d583e4b004e67dc9d2f898fd798112434e7a9
Reviewed-on: https://go-review.googlesource.com/12026
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Russ Cox <rsc@golang.org>
2015-07-13 19:42:35 +00:00
Brad Fitzpatrick
2ae77376f7 all: link to https instead of http
The one in misc/makerelease/makerelease.go is particularly bad and
probably warrants rotating our keys.

I didn't update old weekly notes, and reverted some changes involving
test code for now, since we're late in the Go 1.5 freeze. Otherwise,
the rest are all auto-generated changes, and all manually reviewed.

Change-Id: Ia2753576ab5d64826a167d259f48a2f50508792d
Reviewed-on: https://go-review.googlesource.com/12048
Reviewed-by: Rob Pike <r@golang.org>
2015-07-11 14:36:33 +00:00
Russ Cox
9f90f31c3a cmd/compile: allow static init for unsafe.Pointer(&x) where x is global
This avoids both a write barrier and then dynamic initialization
globals of the form

	var x something
	var xp = unsafe.Pointer(&x)

Using static initialization avoids emitting a relocation for &x,
which helps cgo.

Fixes #9411.

Change-Id: I0dbf480859cce6ab57ab805d1b8609c45b48f156
Reviewed-on: https://go-review.googlesource.com/11693
Reviewed-by: Austin Clements <austin@google.com>
Run-TryBot: Russ Cox <rsc@golang.org>
2015-07-07 21:51:57 +00:00
Russ Cox
6f80e5edf4 cmd/link: reject data size > 2 GB
We can't address more than this on amd64 anyway.

Fixes #9862.

Change-Id: Ifb1abae558e2e1ee2dc953a76995f3f08c60b1df
Reviewed-on: https://go-review.googlesource.com/11715
Reviewed-by: Austin Clements <austin@google.com>
2015-06-30 19:40:39 +00:00
Russ Cox
1122836b5f cmd/compile: reject large floating point exponents without math/big
For #11326 (but not a fix).

Change-Id: Ic51814f5cd7357427c3fd990a5522775d05e7987
Reviewed-on: https://go-review.googlesource.com/11673
Reviewed-by: Robert Griesemer <gri@golang.org>
2015-06-29 21:18:01 +00:00
Russ Cox
69f0d4c6be cmd/link: detect -X setting non-string variable
Fixes #9621.

Change-Id: Ib9c6001378364af899f57fd4b89fb23af2042923
Reviewed-on: https://go-review.googlesource.com/11694
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Russ Cox <rsc@golang.org>
2015-06-29 20:28:36 +00:00
Russ Cox
55203c7dd5 cmd/compile: allow unnamed constants to set line number
Fixes #8836.

Change-Id: Idda9f4a987e03b3bdf5e8fdb984fe56d6f84aa59
Reviewed-on: https://go-review.googlesource.com/11672
Reviewed-by: David Chase <drchase@google.com>
2015-06-29 17:35:55 +00:00
Austin Clements
840965f8d7 runtime: always clear stack barriers on G exit
Currently the runtime fails to clear a G's stack barriers in gfput if
the G's stack allocation is _FixedStack bytes. This causes the runtime
to panic if the following sequence of events happens:

1) The runtime installs stack barriers on a G.

2) The G exits by calling runtime.Goexit. Since this does not
   necessarily return through the stack barriers installed on the G,
   there may still be untriggered stack barriers left on the G's stack
   in recorded in g.stkbar.

3) The runtime calls gfput to add the exiting G to the free pool. If
   the G's stack allocation is _FixedStack bytes, we fail to clear
   g.stkbar.

4) A new G starts and allocates the G that was just added to the free
   pool.

5) The new G begins to execute and overwrites the stack slots that had
   stack barriers in them.

6) The garbage collector enters mark termination, attempts to remove
   stack barriers from the new G, and finds that they've been
   overwritten.

Fix this by clearing the stack barriers in gfput in the case where it
reuses the stack.

Fixes #11256.

Change-Id: I377c44258900e6bcc2d4b3451845814a8eeb2bcf
Reviewed-on: https://go-review.googlesource.com/11461
Reviewed-by: Alex Brainman <alex.brainman@gmail.com>
Reviewed-by: Russ Cox <rsc@golang.org>
2015-06-29 15:02:30 +00:00
Dave Cheney
834fef80ae test: add test case for issue 8154
Updates #8154

Change-Id: Ie9c731a91b008277e51c723eef6871bb0919fa4c
Reviewed-on: https://go-review.googlesource.com/10831
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Russ Cox <rsc@golang.org>
2015-06-26 17:58:22 +00:00
Todd Neal
765c0f37ed cmd/compile: fix half multiply issue
In walkdiv, an OMUL node was created and passed to typecheck,
before the op was changed back to OHMUL.  In some instances,
the node that came back was an evaluated literal constant that
occurred with a full multiply.  The end result was a literal node
with a non-shifted value and an OHMUL op. This change causes code
to be generated for the OHMUL.

Fixes #11358
Fixes #11369

Change-Id: If42a98c6830d07fe065d5ca57717704fb8cfbd33
Reviewed-on: https://go-review.googlesource.com/11400
Reviewed-by: Russ Cox <rsc@golang.org>
2015-06-26 15:55:22 +00:00
Aaron Jacobs
8628688304 Fix several out of date references to 4g/5g/6g/8g/9g.
Change-Id: Ifb8e4e13c7778a7c0113190051415e096f5db94f
Reviewed-on: https://go-review.googlesource.com/11390
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Andrew Gerrand <adg@golang.org>
2015-06-26 03:38:21 +00:00
Russ Cox
66130907d1 cmd/compile: handle copy in escape analysis
Somehow we missed this!
Fixes #11387.

Change-Id: Ida08fe52eff7da2ef7765b4cf35a39a301420c43
Reviewed-on: https://go-review.googlesource.com/11460
Reviewed-by: David Chase <drchase@google.com>
2015-06-24 22:22:55 +00:00
Austin Clements
a8ae93fd26 runtime: fix heap bitmap repeating with large scalar tails
When heapBitsSetType repeats a source bitmap with a scalar tail
(typ.ptrdata < typ.size), it lays out the tail upon reaching the end
of the source bitmap by simply increasing the number of bits claimed
to be in the incoming bit buffer. This causes later iterations to read
the appropriate number of zeros out of the bit buffer before starting
on the next repeat of the source bitmap.

Currently, however, later iterations of the loop continue to read bits
from the source bitmap *regardless of the number of bits currently in
the bit buffer*. The bit buffer can only hold 32 or 64 bits, so if the
scalar tail is large and the padding bits exceed the size of the bit
buffer, the read from the source bitmap on the next iteration will
shift the incoming bits into oblivion when it attempts to put them in
the bit buffer. When the buffer does eventually shift down to where
these bits were supposed to be, it will contain zeros. As a result,
words that should be marked as pointers on later repetitions are
marked as scalars, so the garbage collector does not trace them. If
this is the only reference to an object, it will be incorrectly freed.

Fix this by adding logic to drain the bit buffer down if it is large
instead of reading more bits from the source bitmap.

Fixes #11286.

Change-Id: I964432c4b9f1cec334fc8c3da0ff16460203feb6
Reviewed-on: https://go-review.googlesource.com/11360
Reviewed-by: Russ Cox <rsc@golang.org>
2015-06-23 18:37:17 +00:00
Michael Matloob
32f2f72c47 cmd/compile: provide better error when method called without receiver
When a method is called using the Type.Method(receiver, args...) syntax
without the receiver, or enough arguments, provide the more helpful
error message "not enough arguments in call to method expression
Type.Method" instead of the old message "not enough arguments in call
to Type.Method".

Fixes #8385

Change-Id: Id5037eb1ee5fa93687d4a6557b4a8233b29e9df2
Reviewed-on: https://go-review.googlesource.com/2193
Reviewed-by: Russ Cox <rsc@golang.org>
2015-06-18 19:37:38 +00:00
David Chase
5be61b18d4 cmd/compile: run escape analysis after method wrapper generation
Also modified test/run.go to ignore messages prefixed <autogenerated>
because those cannot be described with "// ERROR ...", and backed out
patch from issue #9537 because it is no longer necessary.  The reasons
described in the 9537 discussion for why escape analysis cannot run
late no longer hold, happily.

Fixes #11053.

Change-Id: Icb14eccdf2e8cde3d0f8fb8a216b765400a96385
Reviewed-on: https://go-review.googlesource.com/11088
Reviewed-by: Russ Cox <rsc@golang.org>
Run-TryBot: David Chase <drchase@google.com>
2015-06-17 02:36:45 +00:00
Josh Bleecher Snyder
a44becef4a cmd/compile: use generated temps in bool codegen
Bool codegen was generating a temp for function calls
and other complex expressions, but was not using it.

This was a refactoring bug introduced by CL 7853.
The cmp code used to do (in short):

	l, r := &n1, &n2

It was changed to:

	l, r := nl, nr

But the requisite assignments:

	nl, nr = &n1, &n2

were only introduced on one of two code paths.

Fixes #10654.

Change-Id: Ie8de0b3a333842a048d4308e02911bb10c6915ce
Reviewed-on: https://go-review.googlesource.com/10844
Reviewed-by: Minux Ma <minux@golang.org>
Run-TryBot: Minux Ma <minux@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2015-06-09 17:38:26 +00:00
Josh Bleecher Snyder
494ff188f8 cmd/compile: early typecheck top level OAS2 nodes
Fixes #10977.

Change-Id: I706c953c16daad48595c7fae2d82124614dfc3ad
Reviewed-on: https://go-review.googlesource.com/10780
Reviewed-by: David Chase <drchase@google.com>
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
2015-06-09 00:25:02 +00:00
Shenghou Ma
21ec72c2ca test: fix build on GOARCH=ppc64/ppc64le
Change-Id: Ibf2879c0034250c5699e21ecea0eb76340597a2a
Reviewed-on: https://go-review.googlesource.com/10810
Reviewed-by: Austin Clements <austin@google.com>
2015-06-06 20:22:57 +00:00
Russ Cox
12795c02f3 cmd/link: deprecate -X name value in favor of -X name=value
People invoking the linker directly already have to change their scripts
to use the new "go tool link", so this is a good time to make the -X flag
behave like all other Go flags and take just a single argument.

The old syntax will continue to be accepted (it is rewritten into the new
syntax before flag parsing). Maybe some day we will be able to retire it.

Even if we never retire the old syntax, having the new syntax at least
makes the rewriting much less of a kludge.

Change-Id: I91e8df94f4c22b2186e81d7f1016b8767d777eac
Reviewed-on: https://go-review.googlesource.com/10310
Reviewed-by: Rob Pike <r@golang.org>
2015-06-05 04:55:41 +00:00
Brad Fitzpatrick
ec745fc4cb test: make test/run.go support sharding
Also modifies 'dist test' to use that sharding, and removes some old
temporary stuff from dist test which are no longer required.

'dist test' now also supports running a list of tests given in
arguments, mutually exclusive with the existing -run=REGEXP flag. The
hacky fast paths for avoiding the 1 second "go list" latency are now
removed and only apply to the case where partial tests are run via
args, instead of regex.  The build coordinator will use both styles
for awhile. (the statically-sharded ARM builders on scaleway will
continue to use regexps, but the dynamically-shared builders on GCE
will use the list of tests)

Updates #10029

Change-Id: I557800a54dfa6f3b5100ef4c26fe397ba5189813
Reviewed-on: https://go-review.googlesource.com/10688
Reviewed-by: Andrew Gerrand <adg@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2015-06-04 19:45:29 +00:00
Russ Cox
73d109c509 cmd/internal/gc: accept map literals with omitted key type
Fixes #10209.

Change-Id: I248434f9195c868befd1ed8a6000a9cac72d1df8
Reviewed-on: https://go-review.googlesource.com/10263
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2015-06-04 02:31:38 +00:00
Russ Cox
fd2154f906 cmd/compile: move Node.Curfn into both Node.Func and Node.Name
$ sizeof -p cmd/compile/internal/gc Node
Node 168
$

Change-Id: If624a2d72ec04ef30a1bc7ce76c0d61a526d8a37
Reviewed-on: https://go-review.googlesource.com/10532
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2015-06-03 20:09:52 +00:00
Josh Bleecher Snyder
3ba6387bd0 test: re-enable rotate tests
Memory usage has been reduced.
The tests are still slow,
but that is issue #10571.

/usr/bin/time shows significant variation
in the peak memory usage compiling with tip.
This is unsurprising, given GC.

Using Go 1.4.2, memory is stable at 410mb.
Using tip at d2ee09298,
memory ranges from 470mb (+15%) to 534mb (+30%),
with a mean of 504mb (+23%), with n=50.

Fixes #9933.

Change-Id: Id31f3ae086ec324abf70e8f1a8044c4a0c27e274
Reviewed-on: https://go-review.googlesource.com/10211
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2015-05-28 19:40:58 +00:00
David Chase
596bb76248 cmd/compile: reject p-notation floats in Go source files
Use pkgimport == nil (or not) to distinguish between
parsing .go source files where "p" exponent specifier
is not allowed and parsing .a or .o export data where
it is.  Use that to control error when p-exponent is
seen.

Fixes #9036

Change-Id: I8924f09c91d4945ef3f20e80a6e544008a94a7e4
Reviewed-on: https://go-review.googlesource.com/10450
Reviewed-by: Russ Cox <rsc@golang.org>
2015-05-28 18:52:14 +00:00
Josh Bleecher Snyder
8b186df731 test: remove arch char from nosplit
This is dead code that was missed
during the 'go tool compile' migration.

Change-Id: Ice2af8a9ef72f8fd5f82225ee261854d93b659f1
Reviewed-on: https://go-review.googlesource.com/10430
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2015-05-28 02:30:26 +00:00
David Chase
05d8f1d166 cmd/compile: propagate correct line numbers in treecopy
Added a lineno parameter to treecopy and listtreecopy
(ignored if = 0).  When nodes are copied the copy is
assigned the non-zero lineno (normally this would be
the destination).

Fixes #8183

Change-Id: Iffb767a745093fb89aa08bf8a7692c2f0122be98
Reviewed-on: https://go-review.googlesource.com/10334
Reviewed-by: Russ Cox <rsc@golang.org>
2015-05-27 17:29:15 +00:00
David Chase
e5060c7f75 cmd/internal/gc: move check for large-hence-heap-allocated types into escape analysis
Before this change, the check for too-large arrays (and other large
types) occurred after escape analysis.  If the data moved off stack
and onto the heap contained any pointers, it would therefore escape,
but because the too-large check occurred after escape analysis this
would not be recorded and a stack pointer would leak to the heap
(see the modified escape_array.go for an example).

Some of these appear to remain, in calls to typecheck from within walk.

Also corrected a few comments in escape_array.go about "BAD"
analysis that is now done correctly.

Enhanced to move aditional EscNone-but-large-so-heap checks into esc.c.

Change-Id: I770c111baff28a9ed5f8beb601cf09dacc561b83
Reviewed-on: https://go-review.googlesource.com/10268
Reviewed-by: Russ Cox <rsc@golang.org>
2015-05-22 02:13:54 +00:00
David Chase
b19ec6842d cmd/internal/gc: make indirect calls properly escape-y
Indirect function and method calls should leak everything,
but they didn't.

This fix had no particular effect on the cost of running the
compiler on html/template/*.go and added a single new "escape"
to the standard library:

    syscall/syscall_unix.go:85: &b[0] escapes to heap
in
	if errno := m.munmap(uintptr(unsafe.Pointer(&b[0])),
	                     uintptr(len(b))); errno != nil {

Added specific escape testing to escape_calls.go
(and verified that it fails without this patch)

I also did a little code cleanup around the changes in esc.c.

Fixes #10925

Change-Id: I9984b701621ad4c49caed35b01e359295c210033
Reviewed-on: https://go-review.googlesource.com/10295
Reviewed-by: Russ Cox <rsc@golang.org>
2015-05-22 01:36:11 +00:00
Russ Cox
cf932cd897 all: retire architecture letter in file names, public API
This CL removes the remaining visible uses of the "architecture letter" concept.
(They are no longer in tool names nor in source directory names.)

Because the architecture letter concept is now gone, delete GOCHAR
from "go env" output, and change go/build.ArchChar to return an
error always.

The architecture letter is still used in the compiler and linker sources
as a clumsy architecture enumeration, but that use is not visible to
Go users and can be cleaned up separately.

Change-Id: I4d97a38f372003fb610c9c5241bea440d9dbeb8d
Reviewed-on: https://go-review.googlesource.com/10289
Reviewed-by: Rob Pike <r@golang.org>
2015-05-21 17:32:17 +00:00
Russ Cox
0f4132c907 all: build and use go tool compile, go tool link
This CL fixes the build to use the newly created go tool compile
and go tool link in place of go tool 5g, go tool 5l, and so on.

See golang-dev thread titled "go tool compile, etc" for background.

Although it was not a primary motivation, this conversion does
reduce the wall clock time and cpu time required for make.bash
by about 10%.

Change-Id: I79cbbdb676cab029db8aeefb99a53178ff55f98d
Reviewed-on: https://go-review.googlesource.com/10288
Reviewed-by: Rob Pike <r@golang.org>
2015-05-21 17:32:03 +00:00
Russ Cox
c735064cde cmd/internal/gc: type of str[i] is byte, not uint8
Fixes #8745.

Change-Id: Id0641e3c0f259812b41ed871e83c68740feb2b19
Reviewed-on: https://go-review.googlesource.com/10261
Reviewed-by: Austin Clements <austin@google.com>
2015-05-19 19:20:25 +00:00
Russ Cox
366ba526e8 cmd/internal/gc: add missing write barrier in append(x, BigStructWithPointers)
Fixes #10897.

Change-Id: I5c2d1f9d26333e2b2a0613ebf496daa465e07c24
Reviewed-on: https://go-review.googlesource.com/10221
Reviewed-by: Austin Clements <austin@google.com>
2015-05-19 15:28:29 +00:00
David Chase
a21cf5b6a2 cmd/internal/gc: extend escape analysis to pointers in slices
Modified esc.go to allow slice literals (before append)
to be non-escaping.  Modified tests to account for changes
in escape behavior and to also test the two cases that
were previously not tested.

Also minor cleanups to debug-printing within esc.go

Allocation stats for running compiler
( cd src/html/template;
  for i in {1..5} ; do
     go tool 6g -memprofile=testzz.${i}.prof  -memprofilerate=1 *.go ;
     go tool pprof -alloc_objects -text  testzz.${i}.prof ;
     done ; )
before about 86k allocations
after  about 83k allocations

Fixes #8972

Change-Id: Ib61dd70dc74adb40d6f6fdda6eaa4bf7d83481de
Reviewed-on: https://go-review.googlesource.com/10118
Reviewed-by: Russ Cox <rsc@golang.org>
2015-05-18 15:34:39 +00:00
Brad Fitzpatrick
97494a45e2 Revert "cmd/internal/gc: ignore declarations of types for goto validation"
This reverts commit 5726af54eb.

It broke all the builds.

Change-Id: I4b1dde86f9433717d303c1dabd6aa1a2bf97fab2
Reviewed-on: https://go-review.googlesource.com/10143
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2015-05-15 16:35:49 +00:00
Daniel Morsing
5726af54eb cmd/internal/gc: ignore declarations of types for goto validation
Fixes #8042.

Change-Id: I75080f24104256065fd73b07a13c5b8e7d6da94c
Reviewed-on: https://go-review.googlesource.com/9442
Reviewed-by: Russ Cox <rsc@golang.org>
2015-05-15 16:03:47 +00:00
Russ Cox
d447279927 cmd/internal/gc: optimize slice + write barrier
The code generated for a slice x[i:j] or x[i:j:k] computes the entire
new slice (base, len, cap) and then uses it as the evaluation of the
slice expression.

If the slice is part of an update x = x[i:j] or x = x[i:j:k], there are
opportunities to avoid computing some of these fields.

For x = x[0:i], we know that only the len is changing;
base can be ignored completely, and cap can be left unmodified.

For x = x[0:i:j], we know that only len and cap are changing;
base can be ignored completely.

For x = x[i:i], we know that the resulting cap is zero, and we don't
adjust the base during a slice producing a zero-cap result,
so again base can be ignored completely.

No write to base, no write barrier.

The old slice code was trying to work at a Go syntax level, mainly
because that was how you wrote code just once instead of once
per architecture. Now the compiler is factored a bit better and we
can implement slice during code generation but still have one copy
of the code. So the new code is working at that lower level.
(It must, to update only parts of the result.)

This CL by itself:
name                   old mean              new mean              delta
BinaryTree17            5.81s × (0.98,1.03)   5.71s × (0.96,1.05)     ~    (p=0.101)
Fannkuch11              4.35s × (1.00,1.00)   4.39s × (1.00,1.00)   +0.79% (p=0.000)
FmtFprintfEmpty        86.0ns × (0.94,1.11)  82.6ns × (0.98,1.04)   -3.86% (p=0.048)
FmtFprintfString        276ns × (0.98,1.04)   273ns × (0.98,1.02)     ~    (p=0.235)
FmtFprintfInt           274ns × (0.98,1.06)   270ns × (0.99,1.01)     ~    (p=0.119)
FmtFprintfIntInt        506ns × (0.99,1.01)   475ns × (0.99,1.01)   -6.02% (p=0.000)
FmtFprintfPrefixedInt   391ns × (0.99,1.01)   393ns × (1.00,1.01)     ~    (p=0.139)
FmtFprintfFloat         566ns × (0.99,1.01)   574ns × (1.00,1.01)   +1.33% (p=0.001)
FmtManyArgs            1.91µs × (0.99,1.01)  1.87µs × (0.99,1.02)   -1.83% (p=0.000)
GobDecode              15.3ms × (0.99,1.02)  15.0ms × (0.98,1.05)   -1.84% (p=0.042)
GobEncode              11.5ms × (0.97,1.03)  11.4ms × (0.99,1.03)     ~    (p=0.152)
Gzip                    645ms × (0.99,1.01)   647ms × (0.99,1.01)     ~    (p=0.265)
Gunzip                  142ms × (1.00,1.00)   143ms × (1.00,1.01)   +0.90% (p=0.000)
HTTPClientServer       90.5µs × (0.97,1.04)  88.5µs × (0.99,1.03)   -2.27% (p=0.014)
JSONEncode             32.0ms × (0.98,1.03)  29.6ms × (0.98,1.01)   -7.51% (p=0.000)
JSONDecode              114ms × (0.99,1.01)   104ms × (1.00,1.01)   -8.60% (p=0.000)
Mandelbrot200          6.04ms × (1.00,1.01)  6.02ms × (1.00,1.00)     ~    (p=0.057)
GoParse                6.47ms × (0.97,1.05)  6.37ms × (0.97,1.04)     ~    (p=0.105)
RegexpMatchEasy0_32     171ns × (0.93,1.07)   152ns × (0.99,1.01)  -11.09% (p=0.000)
RegexpMatchEasy0_1K     550ns × (0.98,1.01)   530ns × (1.00,1.00)   -3.78% (p=0.000)
RegexpMatchEasy1_32     135ns × (0.99,1.02)   134ns × (0.99,1.01)   -1.33% (p=0.002)
RegexpMatchEasy1_1K     879ns × (1.00,1.01)   865ns × (1.00,1.00)   -1.58% (p=0.000)
RegexpMatchMedium_32    243ns × (1.00,1.00)   233ns × (1.00,1.00)   -4.30% (p=0.000)
RegexpMatchMedium_1K   70.3µs × (1.00,1.00)  69.5µs × (1.00,1.00)   -1.13% (p=0.000)
RegexpMatchHard_32     3.82µs × (1.00,1.01)  3.74µs × (1.00,1.00)   -1.95% (p=0.000)
RegexpMatchHard_1K      117µs × (1.00,1.00)   115µs × (1.00,1.00)   -1.69% (p=0.000)
Revcomp                 917ms × (0.97,1.04)   920ms × (0.97,1.04)     ~    (p=0.786)
Template                114ms × (0.99,1.01)   117ms × (0.99,1.01)   +2.58% (p=0.000)
TimeParse               622ns × (0.99,1.01)   615ns × (0.99,1.00)   -1.06% (p=0.000)
TimeFormat              665ns × (0.99,1.01)   654ns × (0.99,1.00)   -1.70% (p=0.000)

This CL and previous CL (append) combined:
name                   old mean              new mean              delta
BinaryTree17            5.68s × (0.97,1.04)   5.71s × (0.96,1.05)     ~    (p=0.638)
Fannkuch11              4.41s × (0.98,1.03)   4.39s × (1.00,1.00)     ~    (p=0.474)
FmtFprintfEmpty        92.7ns × (0.91,1.16)  82.6ns × (0.98,1.04)  -10.89% (p=0.004)
FmtFprintfString        281ns × (0.96,1.08)   273ns × (0.98,1.02)     ~    (p=0.078)
FmtFprintfInt           288ns × (0.97,1.06)   270ns × (0.99,1.01)   -6.37% (p=0.000)
FmtFprintfIntInt        493ns × (0.97,1.04)   475ns × (0.99,1.01)   -3.53% (p=0.002)
FmtFprintfPrefixedInt   423ns × (0.97,1.04)   393ns × (1.00,1.01)   -7.07% (p=0.000)
FmtFprintfFloat         598ns × (0.99,1.01)   574ns × (1.00,1.01)   -4.02% (p=0.000)
FmtManyArgs            1.89µs × (0.98,1.05)  1.87µs × (0.99,1.02)     ~    (p=0.305)
GobDecode              14.8ms × (0.98,1.03)  15.0ms × (0.98,1.05)     ~    (p=0.237)
GobEncode              12.3ms × (0.98,1.01)  11.4ms × (0.99,1.03)   -6.95% (p=0.000)
Gzip                    656ms × (0.99,1.05)   647ms × (0.99,1.01)     ~    (p=0.101)
Gunzip                  142ms × (1.00,1.00)   143ms × (1.00,1.01)   +0.58% (p=0.001)
HTTPClientServer       91.2µs × (0.97,1.04)  88.5µs × (0.99,1.03)   -3.02% (p=0.003)
JSONEncode             32.6ms × (0.97,1.08)  29.6ms × (0.98,1.01)   -9.10% (p=0.000)
JSONDecode              114ms × (0.97,1.05)   104ms × (1.00,1.01)   -8.74% (p=0.000)
Mandelbrot200          6.11ms × (0.98,1.04)  6.02ms × (1.00,1.00)     ~    (p=0.090)
GoParse                6.66ms × (0.97,1.04)  6.37ms × (0.97,1.04)   -4.41% (p=0.000)
RegexpMatchEasy0_32     159ns × (0.99,1.00)   152ns × (0.99,1.01)   -4.69% (p=0.000)
RegexpMatchEasy0_1K     538ns × (1.00,1.01)   530ns × (1.00,1.00)   -1.57% (p=0.000)
RegexpMatchEasy1_32     138ns × (1.00,1.00)   134ns × (0.99,1.01)   -2.91% (p=0.000)
RegexpMatchEasy1_1K     869ns × (0.99,1.01)   865ns × (1.00,1.00)   -0.51% (p=0.012)
RegexpMatchMedium_32    252ns × (0.99,1.01)   233ns × (1.00,1.00)   -7.85% (p=0.000)
RegexpMatchMedium_1K   72.7µs × (1.00,1.00)  69.5µs × (1.00,1.00)   -4.43% (p=0.000)
RegexpMatchHard_32     3.85µs × (1.00,1.00)  3.74µs × (1.00,1.00)   -2.74% (p=0.000)
RegexpMatchHard_1K      118µs × (1.00,1.00)   115µs × (1.00,1.00)   -2.24% (p=0.000)
Revcomp                 920ms × (0.97,1.07)   920ms × (0.97,1.04)     ~    (p=0.998)
Template                129ms × (0.98,1.03)   117ms × (0.99,1.01)   -9.79% (p=0.000)
TimeParse               619ns × (0.99,1.01)   615ns × (0.99,1.00)   -0.57% (p=0.011)
TimeFormat              661ns × (0.98,1.04)   654ns × (0.99,1.00)     ~    (p=0.223)

Change-Id: If054d81ab2c71d8d62cf54b5b1fac2af66b387fc
Reviewed-on: https://go-review.googlesource.com/9813
Reviewed-by: David Chase <drchase@google.com>
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2015-05-13 19:20:39 +00:00
Robert Griesemer
99475dfb59 cmd/internal/gc: avoid spurious div-zero errors
Set overflowing integer constants to 1 rather than 0 to avoid
spurious div-zero errors in subsequent constant expressions.

Also: Exclude new test case from go/types test since it's
running too long (go/types doesn't have an upper constant
size limit at the moment).

Fixes #7746.

Change-Id: I3768488ad9909a3cf995247b81ee78a8eb5a1e41
Reviewed-on: https://go-review.googlesource.com/9165
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2015-05-13 17:38:13 +00:00
Russ Cox
8552047a32 cmd/internal/gc: optimize append + write barrier
The code generated for x = append(x, v) is roughly:

	t := x
	if len(t)+1 > cap(t) {
		t = grow(t)
	}
	t[len(t)] = v
	len(t)++
	x = t

We used to generate this code as Go pseudocode during walk.
Generate it instead as actual instructions during gen.

Doing so lets us apply a few optimizations. The most important
is that when, as in the above example, the source slice and the
destination slice are the same, the code can instead do:

	t := x
	if len(t)+1 > cap(t) {
		t = grow(t)
		x = {base(t), len(t)+1, cap(t)}
	} else {
		len(x)++
	}
	t[len(t)] = v

That is, in the fast path that does not reallocate the array,
only the updated length needs to be written back to x,
not the array pointer and not the capacity. This is more like
what you'd write by hand in C. It's faster in general, since
the fast path elides two of the three stores, but it's especially
faster when the form of x is such that the base pointer write
would turn into a write barrier. No write, no barrier.

name                   old mean              new mean              delta
BinaryTree17            5.68s × (0.97,1.04)   5.81s × (0.98,1.03)   +2.35% (p=0.023)
Fannkuch11              4.41s × (0.98,1.03)   4.35s × (1.00,1.00)     ~    (p=0.090)
FmtFprintfEmpty        92.7ns × (0.91,1.16)  86.0ns × (0.94,1.11)   -7.31% (p=0.038)
FmtFprintfString        281ns × (0.96,1.08)   276ns × (0.98,1.04)     ~    (p=0.219)
FmtFprintfInt           288ns × (0.97,1.06)   274ns × (0.98,1.06)   -4.94% (p=0.002)
FmtFprintfIntInt        493ns × (0.97,1.04)   506ns × (0.99,1.01)   +2.65% (p=0.009)
FmtFprintfPrefixedInt   423ns × (0.97,1.04)   391ns × (0.99,1.01)   -7.52% (p=0.000)
FmtFprintfFloat         598ns × (0.99,1.01)   566ns × (0.99,1.01)   -5.27% (p=0.000)
FmtManyArgs            1.89µs × (0.98,1.05)  1.91µs × (0.99,1.01)     ~    (p=0.231)
GobDecode              14.8ms × (0.98,1.03)  15.3ms × (0.99,1.02)   +3.01% (p=0.000)
GobEncode              12.3ms × (0.98,1.01)  11.5ms × (0.97,1.03)   -5.93% (p=0.000)
Gzip                    656ms × (0.99,1.05)   645ms × (0.99,1.01)     ~    (p=0.055)
Gunzip                  142ms × (1.00,1.00)   142ms × (1.00,1.00)   -0.32% (p=0.034)
HTTPClientServer       91.2µs × (0.97,1.04)  90.5µs × (0.97,1.04)     ~    (p=0.468)
JSONEncode             32.6ms × (0.97,1.08)  32.0ms × (0.98,1.03)     ~    (p=0.190)
JSONDecode              114ms × (0.97,1.05)   114ms × (0.99,1.01)     ~    (p=0.887)
Mandelbrot200          6.11ms × (0.98,1.04)  6.04ms × (1.00,1.01)     ~    (p=0.167)
GoParse                6.66ms × (0.97,1.04)  6.47ms × (0.97,1.05)   -2.81% (p=0.014)
RegexpMatchEasy0_32     159ns × (0.99,1.00)   171ns × (0.93,1.07)   +7.19% (p=0.002)
RegexpMatchEasy0_1K     538ns × (1.00,1.01)   550ns × (0.98,1.01)   +2.30% (p=0.000)
RegexpMatchEasy1_32     138ns × (1.00,1.00)   135ns × (0.99,1.02)   -1.60% (p=0.000)
RegexpMatchEasy1_1K     869ns × (0.99,1.01)   879ns × (1.00,1.01)   +1.08% (p=0.000)
RegexpMatchMedium_32    252ns × (0.99,1.01)   243ns × (1.00,1.00)   -3.71% (p=0.000)
RegexpMatchMedium_1K   72.7µs × (1.00,1.00)  70.3µs × (1.00,1.00)   -3.34% (p=0.000)
RegexpMatchHard_32     3.85µs × (1.00,1.00)  3.82µs × (1.00,1.01)   -0.81% (p=0.000)
RegexpMatchHard_1K      118µs × (1.00,1.00)   117µs × (1.00,1.00)   -0.56% (p=0.000)
Revcomp                 920ms × (0.97,1.07)   917ms × (0.97,1.04)     ~    (p=0.808)
Template                129ms × (0.98,1.03)   114ms × (0.99,1.01)  -12.06% (p=0.000)
TimeParse               619ns × (0.99,1.01)   622ns × (0.99,1.01)     ~    (p=0.062)
TimeFormat              661ns × (0.98,1.04)   665ns × (0.99,1.01)     ~    (p=0.524)

See next CL for combination with a similar optimization for slice.
The benchmarks that are slower in this CL are still faster overall
with the combination of the two.

Change-Id: I2a7421658091b2488c64741b4db15ab6c3b4cb7e
Reviewed-on: https://go-review.googlesource.com/9812
Reviewed-by: David Chase <drchase@google.com>
2015-05-12 17:55:09 +00:00
Russ Cox
3f209abb29 cmd/internal/gc: detect bad append(f()) during type check
Today's earlier fix can stay, but it's a band-aid over the real problem,
which is that bad code was slipping through the type checker
into the back end (and luckily causing a type error there).

I discovered this because my new append does not use the same
temporaries and failed the test as written.

Fixes #9521.

Change-Id: I7e33e2ea15743406e15c6f3fdf73e1edecda69bd
Reviewed-on: https://go-review.googlesource.com/9921
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2015-05-12 16:26:35 +00:00
Didier Spezia
7c0db1b7e2 cmd/gc: do not display ~b identifiers in error messages
Instead of errors like:

./blank2.go:15: cannot use ~b1 (type []int) as type int in assignment

we now have:

./blank2.go:15: cannot use _ (type []int) as type int in assignment

Less confusing for users.

Fixes #9521

Change-Id: Ieab9859040e8e0df95deeaee7eeb408d3be61c0f
Reviewed-on: https://go-review.googlesource.com/9902
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2015-05-11 17:44:31 +00:00
Josh Bleecher Snyder
a3dfcf51c6 cmd/internal/gc: unsafe.Pointer constants may only be converted to uintptr
Fixes #8927.

Change-Id: I638cddd439dd2d4eeef5474118cfcbde0c8a5a43
Reviewed-on: https://go-review.googlesource.com/9632
Run-TryBot: David Chase <drchase@google.com>
Reviewed-by: David Chase <drchase@google.com>
2015-05-07 23:54:28 +00:00
David Chase
d4bb72b485 cmd/internal/gc: improve "type *X has no field or method M" message
Try to provide hints for common areas, either *interface
were interface would have been better, and note incorrect
capitalization (but don't be more ambitious than that, at
least not today).

Added code and test for cases

  ptrInterface.ExistingMethod
  ptrInterface.unexportedMethod
  ptrInterface.MissingMethod
  ptrInterface.withwRongcASEdMethod
  interface.withwRongcASEdMethod
  ptrStruct.withwRongcASEdMethod
  struct.withwRongcASEdMethod

also included tests for related errors to check for
unintentional changes and consistent wording.

Somewhat simplified from previous versions to avoid second-
guessing user errors, yet also biased to point out most-likely
root cause.

Fixes #10700

Change-Id: I16693e93cc8d8ca195e7742a222d640c262105b4
Reviewed-on: https://go-review.googlesource.com/9731
Reviewed-by: Russ Cox <rsc@golang.org>
2015-05-07 16:21:57 +00:00
Keith Randall
6f42b6166a test: fix nosplit test for noopt build
Noopt builds get a larger stack guard.  This test must take that into account.

Change-Id: I1b5cbafdbbfee8c369ae1bebd0b900524ebf0d7d
Reviewed-on: https://go-review.googlesource.com/9610
Reviewed-by: Russ Cox <rsc@golang.org>
2015-05-03 16:10:40 +00:00
David Chase
7fbb1b36c3 cmd/internal/gc: improve flow of input params to output params
This includes the following information in the per-function summary:

outK = paramJ   encoded in outK bits for paramJ
outK = *paramJ  encoded in outK bits for paramJ
heap = paramJ   EscHeap
heap = *paramJ  EscContentEscapes

Note that (currently) if the address of a parameter is taken and
returned, necessarily a heap allocation occurred to contain that
reference, and the heap can never refer to stack, therefore the
parameter and everything downstream from it escapes to the heap.

The per-function summary information now has a tuneable number of bits
(2 is probably noticeably better than 1, 3 is likely overkill, but it
is now easy to check and the -m debugging output includes information
that allows you to figure out if more would be better.)

A new test was  added to check pointer flow through struct-typed and
*struct-typed parameters and returns; some of these are sensitive to
the number of summary bits, and ought to yield better results with a
more competent escape analysis algorithm.  Another new test checks
(some) correctness with array parameters, results, and operations.

The old analysis inferred a piece of plan9 runtime was non-escaping by
counteracting overconservative analysis with buggy analysis; with the
bug fixed, the result was too conservative (and it's not easy to fix
in this framework) so the source code was tweaked to get the desired
result.  A test was added against the discovered bug.

The escape analysis was further improved splitting the "level" into
3 parts, one tracking the conventional "level" and the other two
computing the highest-level-suffix-from-copy, which is used to
generally model the cancelling effect of indirection applied to
address-of.

With the improved escape analysis enabled, it was necessary to
modify one of the runtime tests because it now attempts to allocate
too much on the (small, fixed-size) G0 (system) stack and this
failed the test.

Compiling src/std after touching src/runtime/*.go with -m logging
turned on shows 420 fewer heap allocation sites (10538 vs 10968).

Profiling allocations in src/html/template with
for i in {1..5} ;
  do go tool 6g -memprofile=mastx.${i}.prof  -memprofilerate=1 *.go;
  go tool pprof -alloc_objects -text  mastx.${i}.prof ;
done

showed a 15% reduction in allocations performed by the compiler.

Update #3753
Update #4720
Fixes #10466

Change-Id: I0fd97d5f5ac527b45f49e2218d158a6e89951432
Reviewed-on: https://go-review.googlesource.com/8202
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2015-05-01 13:47:20 +00:00