Commit graph

31 commits

Author SHA1 Message Date
Ian Lance Taylor
72d90d8238 cmd/compile: change parser, racewalk, range to use nodeSeq
Passes toolstash -cmp.

Update #14473.

Change-Id: I0809c6b88643f04c7fc503f866ffe25e69f29910
Reviewed-on: https://go-review.googlesource.com/20260
Reviewed-by: David Crawshaw <crawshaw@golang.org>
2016-03-05 02:33:00 +00:00
Ian Lance Taylor
55c65d4a97 cmd/compile: change export.go and fmt.go to use nodeSeq
Also fix some uses of nodeSeqIterator.Len, and fix the implementation in
nodesIterator.

Passes toolstash -cmp.

Update #14473.

Change-Id: I228871470234b7f1314ffd2aae8a4c0624c35f98
Reviewed-on: https://go-review.googlesource.com/20231
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2016-03-04 21:46:30 +00:00
Keith Randall
9d854fd44a Merge branch 'dev.ssa' into mergebranch
Merge dev.ssa branch back into master.

Change-Id: Ie6fac3f8d355ab164f934415fe4fc7fcb8c3db16
2016-03-01 12:50:17 -08:00
Keith Randall
4fffd4569d [dev.ssa] Merge remote-tracking branch 'origin/master' into ssamerge
(Last?) Semi-regular merge from tip to dev.ssa.

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

Change-Id: Ib5ea8bf74d420f4902a9c6208761be9f22371ae7
2016-02-29 13:32:20 -08:00
Ian Lance Taylor
1d5001afef cmd/compile: change Node.Nbody, Func.Inl from *NodeList to Nodes
Passes toolstash -cmp.

Casual timings show about a 3% improvement in compile times.

Update #14473.

Change-Id: I584add2e8f1a52486ba418b25ba6122b7347b643
Reviewed-on: https://go-review.googlesource.com/19989
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2016-02-29 00:33:32 +00:00
Ian Lance Taylor
188e3d2515 cmd/compile: change Func.{Enter,Exit} from NodeList to slice
Introduces a new types Nodes that can be used to replace NodeList.

Update #14473.

Change-Id: Id77c5dcae0cbeb898ba12dd46bd400aad408871c
Reviewed-on: https://go-review.googlesource.com/19969
Reviewed-by: David Crawshaw <crawshaw@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2016-02-27 00:59:47 +00:00
Robert Griesemer
3c0fae5306 cmd/compile: track pragmas in lexer rather than global variables
By using a Pragma bit set (8 bits) rather than 8 booleans, also
reduce Func type size by 8 bytes (208B -> 200B on 64bit platforms,
116B -> 108B on 32bit platforms).

Change-Id: Ibb7e1f8c418a0b5bc6ff813cbdde7bc6f0013b5a
Reviewed-on: https://go-review.googlesource.com/19966
Reviewed-by: Dave Cheney <dave@cheney.net>
2016-02-26 22:01:16 +00:00
Keith Randall
23d5810c8f [dev.ssa] Merge remote-tracking branch 'origin/master' into mergebranch
Semi-regular merge from tip to dev.ssa.

Conflicts:
	src/runtime/sys_windows_amd64.s

Change-Id: I5f733130049c810e6ceacd46dad85faebca52b29
2016-01-19 14:13:16 -08:00
Russ Cox
1ac637c766 cmd/compile: recognize Syscall-like functions for liveness analysis
Consider this code:

	func f(*int)

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

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

Now consider this code:

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

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

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

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

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

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

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

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

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

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

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

Fixes #13372.

Change-Id: I2addb83f70d08db08c64d394f9d06ff0a063c500
Reviewed-on: https://go-review.googlesource.com/18584
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2016-01-14 01:16:45 +00:00
Keith Randall
b386c34ef9 [dev.ssa] Merge remote-tracking branch 'origin/master' into mergebranch
Semi-regular merge from tip into dev.ssa.

Change-Id: I1627d7c7e6892cd4f1f5da5f3e07389ff1d677ce
2016-01-07 10:01:08 -08:00
Russ Cox
1babba2e4c cmd/compile: fix -race nit
Fixes #13264.

Change-Id: I74b941164610921a03814733fea08631f18b6178
Reviewed-on: https://go-review.googlesource.com/17815
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2015-12-16 17:20:26 +00:00
Keith Randall
4304fbc4d0 [dev.ssa] Merge remote-tracking branch 'origin/master' into mergebranch
Conflicts:
	src/cmd/compile/internal/gc/racewalk.go
	src/cmd/internal/obj/stack.go
	src/cmd/internal/obj/x86/obj6.go
	src/runtime/stack.go
	test/nilptr3.go
	test/nosplit.go

Change-Id: Ie6053eb1577fd73e8243651f25c0f1fc765ae660
2015-11-16 17:19:42 -08:00
Michael Matloob
432cb66f16 runtime: break out system-specific constants into package sys
runtime/internal/sys will hold system-, architecture- and config-
specific constants.

Updates #11647

Change-Id: I6db29c312556087a42e8d2bdd9af40d157c56b54
Reviewed-on: https://go-review.googlesource.com/16817
Reviewed-by: Russ Cox <rsc@golang.org>
2015-11-12 17:04:45 +00:00
Michael Matloob
67faca7d9c runtime: break atomics out into package runtime/internal/atomic
This change breaks out most of the atomics functions in the runtime
into package runtime/internal/atomic. It adds some basic support
in the toolchain for runtime packages, and also modifies linux/arm
atomics to remove the dependency on the runtime's mutex. The mutexes
have been replaced with spinlocks.

all trybots are happy!
In addition to the trybots, I've tested on the darwin/arm64 builder,
on the darwin/arm builder, and on a ppc64le machine.

Change-Id: I6698c8e3cf3834f55ce5824059f44d00dc8e3c2f
Reviewed-on: https://go-review.googlesource.com/14204
Run-TryBot: Michael Matloob <matloob@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2015-11-10 17:38:04 +00:00
Ian Lance Taylor
9179c9cb5c cmd/compile: make sure instrumented call has type width
The width of the type of an external variable defined with a type
literal may not be set when the instrumentation pass is run.  There are
two cases in the standard library that fail without the call to dowidth:

../../../src/encoding/base32/base32.go:322: constant -1000000000 overflows uintptr
../../../src/encoding/base32/base32.go:329: constant -1000000000 overflows uintptr
../../../src/encoding/json/encode.go:385: constant -1000000000 overflows uintptr
../../../src/encoding/json/encode.go:387: constant -1000000000 overflows uintptr

Change-Id: I7c3334f7decdb7488595ffe4090cd262d7334283
Reviewed-on: https://go-review.googlesource.com/16331
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2015-11-03 23:42:06 +00:00
Ian Lance Taylor
0c69f1303f cmd/compile: add -msan option
The -msan option causes the compiler to add instrumentation for the
C/C++ memory sanitizer.  Every memory read/write will be preceded by
a call to msanread/msanwrite.

This CL passes tests but is not usable by itself.  The actual
implementation of msanread/msanwrite in the runtime package, and support
for -msan in the go tool and the linker, and tests, will follow in
subsequent CLs.

Change-Id: I3d517fb3e6e65d9bf9433db070a420fd11f57816
Reviewed-on: https://go-review.googlesource.com/16160
Reviewed-by: David Crawshaw <crawshaw@golang.org>
2015-10-21 14:58:53 +00:00
Ian Lance Taylor
9e902f0f3a cmd/compile: generalize racewalk to instrument (naming change)
This is mechanical change that is a step toward reusing the racewalk
pass for a more general instrumentation pass.  The first use will be to
add support for the memory sanitizer.

Change-Id: I75b93b814ac60c1db1660e0b9a9a7d7977d86939
Reviewed-on: https://go-review.googlesource.com/16105
Reviewed-by: Hyang-Ah Hana Kim <hyangah@gmail.com>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
2015-10-21 13:55:23 +00:00
Ian Lance Taylor
77b1fef27e cmd/compile, syscall: use go:norace comment for forkAndExecInChild
Use a go:norace comment rather than having the compiler know the special
name syscall.forkAndExecInChild.

Change-Id: I69bc6aa6fc40feb2148d23f269ff32453696fb28
Reviewed-on: https://go-review.googlesource.com/16097
Reviewed-by: Minux Ma <minux@golang.org>
2015-10-20 14:10:24 +00:00
Keith Randall
7c4fbb650c [dev.ssa] Merge remote-tracking branch 'origin/master' into mergebranch
The only major fixup is that duffzero changed from
8-byte writes to 16-byte writes.

Change-Id: I1762b74ce67a8e4b81c11568027cdb3572f7f87c
2015-10-19 14:00:03 -07:00
David Chase
57670ad8b2 [dev.ssa] cmd/compile: fill remaining SSA gaps
Changed racewalk/race detector to use FP in a more
sensible way.

Relaxed checks for CONVNOP when race detecting.

Modified tighten to ensure that GetClosurePtr cannot float
out of entry block (turns out this cannot be relaxed, DX is
sometimes stomped by other code accompanying race detection).

Added case for addr(CONVNOP)

Modified addr to take "bounded" flag to suppress nilchecks
where it is set (usually, by race detector).

Cannot leave unimplemented-complainer enabled because it
turns out we are optimistically running SSA on every platform.

Change-Id: Ife021654ee4065b3ffac62326d09b4b317b9f2e0
Reviewed-on: https://go-review.googlesource.com/15710
Reviewed-by: Keith Randall <khr@golang.org>
2015-10-18 13:30:54 +00:00
Marvin Stenger
2dc63d1544 cmd/compile/internal/gc: cleaning; use range when appropriate
Made use of range statement in for loops.
Cleaning along the way:
-remove unnecessary variable declarations
-rename variables
-remove dead code

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

Change-Id: Ife8c2a98482a81ba91f5bbb65142d9f3dc46d6ee
Reviewed-on: https://go-review.googlesource.com/14379
Run-TryBot: Dave Cheney <dave@cheney.net>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Dave Cheney <dave@cheney.net>
2015-09-17 23:23:01 +00:00
Håvard Haugen
3c9fa388df cmd/compile/internal/gc: rename Fatal to Fatalf
This helps vet see a real issue:

    cmd/internal/gc$ go vet
    gen.go:1223: unreachable code

Fixes #12106.

Change-Id: I720868b07ae6b6d5a4dc6b238baa8c9c889da6d8
Reviewed-on: https://go-review.googlesource.com/14083
Reviewed-by: Minux Ma <minux@golang.org>
Run-TryBot: Minux Ma <minux@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2015-08-31 01:35:23 +00:00
Russ Cox
75d779566b runtime/cgo: make compatible with race detector
Some routines run without and m or g and cannot invoke the
race detector runtime. They must be opaque to the runtime.
That used to be true because they were written in C.
Now that they are written in Go, disable the race detector
annotations for those functions explicitly.

Add test.

Fixes #10874.

Change-Id: Ia8cc28d51e7051528f9f9594b75634e6bb66a785
Reviewed-on: https://go-review.googlesource.com/12534
Reviewed-by: Ian Lance Taylor <iant@golang.org>
2015-07-22 20:28:47 +00:00
Russ Cox
3b6e86f48a cmd/compile: fix race detector handling of OBLOCK nodes
Fixes #7561 correctly.
Fixes #9137.

Change-Id: I7f27e199d7101b785a7645f789e8fe41a405a86f
Reviewed-on: https://go-review.googlesource.com/11713
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
2015-06-30 19:25:18 +00:00
Dmitry Vyukov
cd0a8ed48a cmd/compile: add instrumentation of OKEY
Instrument operands of OKEY.
Also instrument OSLICESTR. Previously it was not needed
because of preceeding bounds checks (which were instrumented).
But the preceeding bounds checks have disappeared.

Change-Id: I3b0de213e23cbcf5b8ef800abeded5eeeb3f8287
Reviewed-on: https://go-review.googlesource.com/11417
Reviewed-by: Russ Cox <rsc@golang.org>
2015-06-26 15:54:03 +00:00
Russ Cox
bd4fff6358 cmd/compile: move ODCLFUNC Node.Nname into Node.Func.Nname
$ sizeof -p cmd/compile/internal/gc Node
Node 168
$

Change-Id: I7decd950fe068c0f294c6c9bff07ef809c394429
Reviewed-on: https://go-review.googlesource.com/10534
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
2015-06-03 20:10:17 +00:00
Russ Cox
66be1481df cmd/compile: remove Node.Ntest, Node.Stkdelta
$ sizeof -p cmd/compile/internal/gc Node
Node 272
$

Change-Id: I3d9b67eebfc0be0a4b9768d3de3dc76300abd89c
Reviewed-on: https://go-review.googlesource.com/10521
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
2015-06-03 17:50:19 +00:00
Russ Cox
ffef180f82 cmd/compile: remove Node.Nincr, Node.Nelse, Node.Initplan
$ sizeof -p cmd/compile/internal/gc Node
Node 288
$

Change-Id: I4e316efa246132b3faa3a892e4fe9c9039250665
Reviewed-on: https://go-review.googlesource.com/10520
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
2015-06-03 17:50:11 +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
Russ Cox
972a478ddf cmd/compile: don't cater to race detector in write barriers
The new lower-level barriers work fine and don't need special handling,
because they appear to the race detector as (visible) ordinary assignments.

Change-Id: I7477d73a3deecbebf68716580678c595cc4151e3
Reviewed-on: https://go-review.googlesource.com/10316
Reviewed-by: Austin Clements <austin@google.com>
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
2015-05-26 13:50:08 +00:00
Russ Cox
17eba6e6b7 cmd/compile, cmd/link: create from 5g, 5l, etc
Trivial merging of 5g, 6g, ... into go tool compile,
and similarlly 5l, 6l, ... into go tool link.
The files compile/main.go and link/main.go are new.
Everything else in those directories is a move followed by
change of imports and package name.

This CL breaks the build. Manual fixups are in the next CL.

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

Change-Id: Id35ff5a5859ad9037c61275d637b1bd51df6828b
Reviewed-on: https://go-review.googlesource.com/10287
Reviewed-by: Dave Cheney <dave@cheney.net>
Reviewed-by: Rob Pike <r@golang.org>
2015-05-21 17:31:51 +00:00
Renamed from src/cmd/internal/gc/racewalk.go (Browse further)