2014-09-24 19:20:03 +00:00
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// errorcheck -0 -N -m -l
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// Copyright 2010 The Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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// Test, using compiler diagnostic flags, that the escape analysis is working.
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// Compiles but does not run. Inlining is disabled.
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// Registerization is disabled too (-N), which should
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// have no effect on escape analysis.
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package foo
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import (
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"fmt"
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"unsafe"
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)
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var gxx *int
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2015-02-19 19:00:11 +00:00
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func foo1(x int) { // ERROR "moved to heap: x$"
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gxx = &x // ERROR "&x escapes to heap$"
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2014-09-24 19:20:03 +00:00
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}
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2015-02-19 19:00:11 +00:00
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func foo2(yy *int) { // ERROR "leaking param: yy$"
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2014-09-24 19:20:03 +00:00
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gxx = yy
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}
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2015-02-19 19:00:11 +00:00
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func foo3(x int) *int { // ERROR "moved to heap: x$"
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return &x // ERROR "&x escapes to heap$"
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2014-09-24 19:20:03 +00:00
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}
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type T *T
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2015-02-19 19:00:11 +00:00
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func foo3b(t T) { // ERROR "leaking param: t$"
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2014-09-24 19:20:03 +00:00
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*t = t
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}
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// xx isn't going anywhere, so use of yy is ok
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2015-02-19 19:00:11 +00:00
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func foo4(xx, yy *int) { // ERROR "foo4 xx does not escape$" "foo4 yy does not escape$"
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2014-09-24 19:20:03 +00:00
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xx = yy
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}
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// xx isn't going anywhere, so taking address of yy is ok
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2015-02-19 19:00:11 +00:00
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func foo5(xx **int, yy *int) { // ERROR "foo5 xx does not escape$" "foo5 yy does not escape$"
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xx = &yy // ERROR "foo5 &yy does not escape$"
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2014-09-24 19:20:03 +00:00
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}
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2015-02-19 19:00:11 +00:00
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func foo6(xx **int, yy *int) { // ERROR "foo6 xx does not escape$" "leaking param: yy$"
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2014-09-24 19:20:03 +00:00
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*xx = yy
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}
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2015-02-19 19:00:11 +00:00
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func foo7(xx **int, yy *int) { // ERROR "foo7 xx does not escape$" "foo7 yy does not escape$"
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2014-09-24 19:20:03 +00:00
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**xx = *yy
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}
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2015-02-19 19:00:11 +00:00
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func foo8(xx, yy *int) int { // ERROR "foo8 xx does not escape$" "foo8 yy does not escape$"
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2014-09-24 19:20:03 +00:00
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xx = yy
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return *xx
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}
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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.${i}.prof ;
done
showed a 15% reduction in allocations performed by the compiler.
Update #3753
Update #4720
Fixes #10466
Change-Id: I0fd97d5f5ac527b45f49e2218d158a6e89951432
Reviewed-on: https://go-review.googlesource.com/8202
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2015-03-26 20:36:15 +00:00
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func foo9(xx, yy *int) *int { // ERROR "leaking param: xx to result ~r2 level=0$" "leaking param: yy to result ~r2 level=0$"
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2014-09-24 19:20:03 +00:00
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xx = yy
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return xx
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}
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2015-02-19 19:00:11 +00:00
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func foo10(xx, yy *int) { // ERROR "foo10 xx does not escape$" "foo10 yy does not escape$"
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2014-09-24 19:20:03 +00:00
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*xx = *yy
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}
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func foo11() int {
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x, y := 0, 42
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2015-02-19 19:00:11 +00:00
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xx := &x // ERROR "foo11 &x does not escape$"
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yy := &y // ERROR "foo11 &y does not escape$"
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2014-09-24 19:20:03 +00:00
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*xx = *yy
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return x
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}
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var xxx **int
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2015-02-19 19:00:11 +00:00
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func foo12(yyy **int) { // ERROR "leaking param: yyy$"
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2014-09-24 19:20:03 +00:00
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xxx = yyy
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}
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// Must treat yyy as leaking because *yyy leaks, and the escape analysis
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// summaries in exported metadata do not distinguish these two cases.
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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>
2015-03-26 20:36:15 +00:00
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func foo13(yyy **int) { // ERROR "leaking param content: yyy$"
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2014-09-24 19:20:03 +00:00
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*xxx = *yyy
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}
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2015-02-19 19:00:11 +00:00
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func foo14(yyy **int) { // ERROR "foo14 yyy does not escape$"
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2014-09-24 19:20:03 +00:00
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**xxx = **yyy
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}
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2015-02-19 19:00:11 +00:00
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func foo15(yy *int) { // ERROR "moved to heap: yy$"
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xxx = &yy // ERROR "&yy escapes to heap$"
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2014-09-24 19:20:03 +00:00
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}
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2015-02-19 19:00:11 +00:00
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func foo16(yy *int) { // ERROR "leaking param: yy$"
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2014-09-24 19:20:03 +00:00
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*xxx = yy
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}
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2015-02-19 19:00:11 +00:00
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func foo17(yy *int) { // ERROR "foo17 yy does not escape$"
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2014-09-24 19:20:03 +00:00
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**xxx = *yy
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}
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2015-02-19 19:00:11 +00:00
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func foo18(y int) { // ERROR "moved to heap: y$"
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*xxx = &y // ERROR "&y escapes to heap$"
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2014-09-24 19:20:03 +00:00
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}
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func foo19(y int) {
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**xxx = y
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}
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type Bar struct {
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i int
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ii *int
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}
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func NewBar() *Bar {
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2015-02-19 19:00:11 +00:00
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return &Bar{42, nil} // ERROR "&Bar literal escapes to heap$"
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2014-09-24 19:20:03 +00:00
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}
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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.${i}.prof ;
done
showed a 15% reduction in allocations performed by the compiler.
Update #3753
Update #4720
Fixes #10466
Change-Id: I0fd97d5f5ac527b45f49e2218d158a6e89951432
Reviewed-on: https://go-review.googlesource.com/8202
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2015-03-26 20:36:15 +00:00
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func NewBarp(x *int) *Bar { // ERROR "leaking param: x to result ~r1 level=-1$"
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2015-02-19 19:00:11 +00:00
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return &Bar{42, x} // ERROR "&Bar literal escapes to heap$"
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2014-09-24 19:20:03 +00:00
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}
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2015-02-19 19:00:11 +00:00
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func NewBarp2(x *int) *Bar { // ERROR "NewBarp2 x does not escape$"
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return &Bar{*x, nil} // ERROR "&Bar literal escapes to heap$"
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2014-09-24 19:20:03 +00:00
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}
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2015-02-19 19:00:11 +00:00
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func (b *Bar) NoLeak() int { // ERROR "\(\*Bar\).NoLeak b does not escape$"
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2014-09-24 19:20:03 +00:00
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return *(b.ii)
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}
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|
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.${i}.prof ;
done
showed a 15% reduction in allocations performed by the compiler.
Update #3753
Update #4720
Fixes #10466
Change-Id: I0fd97d5f5ac527b45f49e2218d158a6e89951432
Reviewed-on: https://go-review.googlesource.com/8202
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2015-03-26 20:36:15 +00:00
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func (b *Bar) Leak() *int { // ERROR "leaking param: b to result ~r0 level=0$"
|
2015-02-19 19:00:11 +00:00
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return &b.i // ERROR "&b.i escapes to heap$"
|
2014-09-24 19:20:03 +00:00
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|
}
|
|
|
|
|
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.${i}.prof ;
done
showed a 15% reduction in allocations performed by the compiler.
Update #3753
Update #4720
Fixes #10466
Change-Id: I0fd97d5f5ac527b45f49e2218d158a6e89951432
Reviewed-on: https://go-review.googlesource.com/8202
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2015-03-26 20:36:15 +00:00
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func (b *Bar) AlsoNoLeak() *int { // ERROR "leaking param: b to result ~r0 level=1$"
|
2014-09-24 19:20:03 +00:00
|
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return b.ii
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}
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|
|
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>
2015-03-26 20:36:15 +00:00
|
|
|
func (b Bar) AlsoLeak() *int { // ERROR "leaking param: b to result ~r0 level=0$"
|
2014-09-24 19:20:03 +00:00
|
|
|
return b.ii
|
|
|
|
}
|
|
|
|
|
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.${i}.prof ;
done
showed a 15% reduction in allocations performed by the compiler.
Update #3753
Update #4720
Fixes #10466
Change-Id: I0fd97d5f5ac527b45f49e2218d158a6e89951432
Reviewed-on: https://go-review.googlesource.com/8202
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2015-03-26 20:36:15 +00:00
|
|
|
func (b Bar) LeaksToo() *int { // ERROR "leaking param: b to result ~r0 level=0$"
|
2015-02-19 19:00:11 +00:00
|
|
|
v := 0 // ERROR "moved to heap: v$"
|
|
|
|
b.ii = &v // ERROR "&v escapes to heap$"
|
2014-09-24 19:20:03 +00:00
|
|
|
return b.ii
|
|
|
|
}
|
|
|
|
|
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>
2015-03-26 20:36:15 +00:00
|
|
|
func (b *Bar) LeaksABit() *int { // ERROR "leaking param: b to result ~r0 level=1$"
|
2015-02-19 19:00:11 +00:00
|
|
|
v := 0 // ERROR "moved to heap: v$"
|
|
|
|
b.ii = &v // ERROR "&v escapes to heap$"
|
2014-09-24 19:20:03 +00:00
|
|
|
return b.ii
|
|
|
|
}
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func (b Bar) StillNoLeak() int { // ERROR "Bar.StillNoLeak b does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
v := 0
|
2015-02-19 19:00:11 +00:00
|
|
|
b.ii = &v // ERROR "Bar.StillNoLeak &v does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
return b.i
|
|
|
|
}
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func goLeak(b *Bar) { // ERROR "leaking param: b$"
|
2014-09-24 19:20:03 +00:00
|
|
|
go b.NoLeak()
|
|
|
|
}
|
|
|
|
|
|
|
|
type Bar2 struct {
|
|
|
|
i [12]int
|
|
|
|
ii []int
|
|
|
|
}
|
|
|
|
|
|
|
|
func NewBar2() *Bar2 {
|
2015-02-19 19:00:11 +00:00
|
|
|
return &Bar2{[12]int{42}, nil} // ERROR "&Bar2 literal escapes to heap$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func (b *Bar2) NoLeak() int { // ERROR "\(\*Bar2\).NoLeak b does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
return b.i[0]
|
|
|
|
}
|
|
|
|
|
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.${i}.prof ;
done
showed a 15% reduction in allocations performed by the compiler.
Update #3753
Update #4720
Fixes #10466
Change-Id: I0fd97d5f5ac527b45f49e2218d158a6e89951432
Reviewed-on: https://go-review.googlesource.com/8202
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2015-03-26 20:36:15 +00:00
|
|
|
func (b *Bar2) Leak() []int { // ERROR "leaking param: b to result ~r0 level=0$"
|
2015-02-19 19:00:11 +00:00
|
|
|
return b.i[:] // ERROR "b.i escapes to heap$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
|
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.${i}.prof ;
done
showed a 15% reduction in allocations performed by the compiler.
Update #3753
Update #4720
Fixes #10466
Change-Id: I0fd97d5f5ac527b45f49e2218d158a6e89951432
Reviewed-on: https://go-review.googlesource.com/8202
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2015-03-26 20:36:15 +00:00
|
|
|
func (b *Bar2) AlsoNoLeak() []int { // ERROR "leaking param: b to result ~r0 level=1$"
|
2014-09-24 19:20:03 +00:00
|
|
|
return b.ii[0:1]
|
|
|
|
}
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func (b Bar2) AgainNoLeak() [12]int { // ERROR "Bar2.AgainNoLeak b does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
return b.i
|
|
|
|
}
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func (b *Bar2) LeakSelf() { // ERROR "leaking param: b$"
|
|
|
|
b.ii = b.i[0:4] // ERROR "b.i escapes to heap$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func (b *Bar2) LeakSelf2() { // ERROR "leaking param: b$"
|
2014-09-24 19:20:03 +00:00
|
|
|
var buf []int
|
2015-02-19 19:00:11 +00:00
|
|
|
buf = b.i[0:] // ERROR "b.i escapes to heap$"
|
2014-09-24 19:20:03 +00:00
|
|
|
b.ii = buf
|
|
|
|
}
|
|
|
|
|
|
|
|
func foo21() func() int {
|
2015-01-19 19:59:58 +00:00
|
|
|
x := 42
|
2015-02-19 19:00:11 +00:00
|
|
|
return func() int { // ERROR "func literal escapes to heap$"
|
2015-01-19 19:59:58 +00:00
|
|
|
return x
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
func foo21a() func() int {
|
2015-02-19 19:00:11 +00:00
|
|
|
x := 42 // ERROR "moved to heap: x$"
|
|
|
|
return func() int { // ERROR "func literal escapes to heap$"
|
|
|
|
x++ // ERROR "&x escapes to heap$"
|
2015-01-19 19:59:58 +00:00
|
|
|
return x
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
func foo22() int {
|
|
|
|
x := 42
|
2015-02-19 19:00:11 +00:00
|
|
|
return func() int { // ERROR "foo22 func literal does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
return x
|
|
|
|
}()
|
|
|
|
}
|
|
|
|
|
2015-01-19 19:59:58 +00:00
|
|
|
func foo23(x int) func() int {
|
2015-02-19 19:00:11 +00:00
|
|
|
return func() int { // ERROR "func literal escapes to heap$"
|
2015-01-19 19:59:58 +00:00
|
|
|
return x
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2015-01-19 19:59:58 +00:00
|
|
|
func foo23a(x int) func() int {
|
2015-02-19 19:00:11 +00:00
|
|
|
f := func() int { // ERROR "func literal escapes to heap$"
|
2015-01-19 19:59:58 +00:00
|
|
|
return x
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
return f
|
|
|
|
}
|
|
|
|
|
2015-01-19 19:59:58 +00:00
|
|
|
func foo23b(x int) *(func() int) {
|
2015-02-19 19:00:11 +00:00
|
|
|
f := func() int { return x } // ERROR "func literal escapes to heap$" "moved to heap: f$"
|
|
|
|
return &f // ERROR "&f escapes to heap$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func foo23c(x int) func() int { // ERROR "moved to heap: x$"
|
|
|
|
return func() int { // ERROR "func literal escapes to heap$"
|
|
|
|
x++ // ERROR "&x escapes to heap$"
|
2015-01-19 19:59:58 +00:00
|
|
|
return x
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2014-09-24 19:20:03 +00:00
|
|
|
func foo24(x int) int {
|
2015-02-19 19:00:11 +00:00
|
|
|
return func() int { // ERROR "foo24 func literal does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
return x
|
|
|
|
}()
|
|
|
|
}
|
|
|
|
|
|
|
|
var x *int
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func fooleak(xx *int) int { // ERROR "leaking param: xx$"
|
2014-09-24 19:20:03 +00:00
|
|
|
x = xx
|
|
|
|
return *x
|
|
|
|
}
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func foonoleak(xx *int) int { // ERROR "foonoleak xx does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
return *x + *xx
|
|
|
|
}
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func foo31(x int) int { // ERROR "moved to heap: x$"
|
|
|
|
return fooleak(&x) // ERROR "&x escapes to heap$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
func foo32(x int) int {
|
2015-02-19 19:00:11 +00:00
|
|
|
return foonoleak(&x) // ERROR "foo32 &x does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
type Foo struct {
|
|
|
|
xx *int
|
|
|
|
x int
|
|
|
|
}
|
|
|
|
|
|
|
|
var F Foo
|
|
|
|
var pf *Foo
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func (f *Foo) fooleak() { // ERROR "leaking param: f$"
|
2014-09-24 19:20:03 +00:00
|
|
|
pf = f
|
|
|
|
}
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func (f *Foo) foonoleak() { // ERROR "\(\*Foo\).foonoleak f does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
F.x = f.x
|
|
|
|
}
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func (f *Foo) Leak() { // ERROR "leaking param: f$"
|
2014-09-24 19:20:03 +00:00
|
|
|
f.fooleak()
|
|
|
|
}
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func (f *Foo) NoLeak() { // ERROR "\(\*Foo\).NoLeak f does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
f.foonoleak()
|
|
|
|
}
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func foo41(x int) { // ERROR "moved to heap: x$"
|
|
|
|
F.xx = &x // ERROR "&x escapes to heap$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func (f *Foo) foo42(x int) { // ERROR "\(\*Foo\).foo42 f does not escape$" "moved to heap: x$"
|
|
|
|
f.xx = &x // ERROR "&x escapes to heap$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func foo43(f *Foo, x int) { // ERROR "foo43 f does not escape$" "moved to heap: x$"
|
|
|
|
f.xx = &x // ERROR "&x escapes to heap$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func foo44(yy *int) { // ERROR "leaking param: yy$"
|
2014-09-24 19:20:03 +00:00
|
|
|
F.xx = yy
|
|
|
|
}
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func (f *Foo) foo45() { // ERROR "\(\*Foo\).foo45 f does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
F.x = f.x
|
|
|
|
}
|
|
|
|
|
|
|
|
// See foo13 above for explanation of why f leaks.
|
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.${i}.prof ;
done
showed a 15% reduction in allocations performed by the compiler.
Update #3753
Update #4720
Fixes #10466
Change-Id: I0fd97d5f5ac527b45f49e2218d158a6e89951432
Reviewed-on: https://go-review.googlesource.com/8202
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2015-03-26 20:36:15 +00:00
|
|
|
func (f *Foo) foo46() { // ERROR "leaking param content: f$"
|
2014-09-24 19:20:03 +00:00
|
|
|
F.xx = f.xx
|
|
|
|
}
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func (f *Foo) foo47() { // ERROR "leaking param: f$"
|
|
|
|
f.xx = &f.x // ERROR "&f.x escapes to heap$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
var ptrSlice []*int
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func foo50(i *int) { // ERROR "leaking param: i$"
|
2014-09-24 19:20:03 +00:00
|
|
|
ptrSlice[0] = i
|
|
|
|
}
|
|
|
|
|
|
|
|
var ptrMap map[*int]*int
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func foo51(i *int) { // ERROR "leaking param: i$"
|
2014-09-24 19:20:03 +00:00
|
|
|
ptrMap[i] = i
|
|
|
|
}
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func indaddr1(x int) *int { // ERROR "moved to heap: x$"
|
|
|
|
return &x // ERROR "&x escapes to heap$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
|
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>
2015-03-26 20:36:15 +00:00
|
|
|
func indaddr2(x *int) *int { // ERROR "leaking param: x to result ~r1 level=0$"
|
2015-02-19 19:00:11 +00:00
|
|
|
return *&x // ERROR "indaddr2 &x does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
|
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>
2015-03-26 20:36:15 +00:00
|
|
|
func indaddr3(x *int32) *int { // ERROR "leaking param: x to result ~r1 level=0$"
|
2015-02-19 19:00:11 +00:00
|
|
|
return *(**int)(unsafe.Pointer(&x)) // ERROR "indaddr3 &x does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
// From package math:
|
|
|
|
|
|
|
|
func Float32bits(f float32) uint32 {
|
2015-02-19 19:00:11 +00:00
|
|
|
return *(*uint32)(unsafe.Pointer(&f)) // ERROR "Float32bits &f does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
func Float32frombits(b uint32) float32 {
|
2015-02-19 19:00:11 +00:00
|
|
|
return *(*float32)(unsafe.Pointer(&b)) // ERROR "Float32frombits &b does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
func Float64bits(f float64) uint64 {
|
2015-02-19 19:00:11 +00:00
|
|
|
return *(*uint64)(unsafe.Pointer(&f)) // ERROR "Float64bits &f does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
func Float64frombits(b uint64) float64 {
|
2015-02-19 19:00:11 +00:00
|
|
|
return *(*float64)(unsafe.Pointer(&b)) // ERROR "Float64frombits &b does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
// contrast with
|
2015-02-19 19:00:11 +00:00
|
|
|
func float64bitsptr(f float64) *uint64 { // ERROR "moved to heap: f$"
|
|
|
|
return (*uint64)(unsafe.Pointer(&f)) // ERROR "&f escapes to heap$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
|
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>
2015-03-26 20:36:15 +00:00
|
|
|
func float64ptrbitsptr(f *float64) *uint64 { // ERROR "leaking param: f to result ~r1 level=0$"
|
2014-09-24 19:20:03 +00:00
|
|
|
return (*uint64)(unsafe.Pointer(f))
|
|
|
|
}
|
|
|
|
|
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.${i}.prof ;
done
showed a 15% reduction in allocations performed by the compiler.
Update #3753
Update #4720
Fixes #10466
Change-Id: I0fd97d5f5ac527b45f49e2218d158a6e89951432
Reviewed-on: https://go-review.googlesource.com/8202
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2015-03-26 20:36:15 +00:00
|
|
|
func typesw(i interface{}) *int { // ERROR "leaking param: i to result ~r1 level=0$"
|
2014-09-24 19:20:03 +00:00
|
|
|
switch val := i.(type) {
|
|
|
|
case *int:
|
|
|
|
return val
|
|
|
|
case *int8:
|
2015-02-19 19:00:11 +00:00
|
|
|
v := int(*val) // ERROR "moved to heap: v$"
|
|
|
|
return &v // ERROR "&v escapes to heap$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
return nil
|
|
|
|
}
|
|
|
|
|
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>
2015-03-26 20:36:15 +00:00
|
|
|
func exprsw(i *int) *int { // ERROR "leaking param: i to result ~r1 level=0$"
|
2014-09-24 19:20:03 +00:00
|
|
|
switch j := i; *j + 110 {
|
|
|
|
case 12:
|
|
|
|
return j
|
|
|
|
case 42:
|
|
|
|
return nil
|
|
|
|
}
|
|
|
|
return nil
|
|
|
|
|
|
|
|
}
|
|
|
|
|
|
|
|
// assigning to an array element is like assigning to the array
|
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.${i}.prof ;
done
showed a 15% reduction in allocations performed by the compiler.
Update #3753
Update #4720
Fixes #10466
Change-Id: I0fd97d5f5ac527b45f49e2218d158a6e89951432
Reviewed-on: https://go-review.googlesource.com/8202
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2015-03-26 20:36:15 +00:00
|
|
|
func foo60(i *int) *int { // ERROR "leaking param: i to result ~r1 level=0$"
|
2014-09-24 19:20:03 +00:00
|
|
|
var a [12]*int
|
|
|
|
a[0] = i
|
|
|
|
return a[1]
|
|
|
|
}
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func foo60a(i *int) *int { // ERROR "foo60a i does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
var a [12]*int
|
|
|
|
a[0] = i
|
|
|
|
return nil
|
|
|
|
}
|
|
|
|
|
|
|
|
// assigning to a struct field is like assigning to the struct
|
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.${i}.prof ;
done
showed a 15% reduction in allocations performed by the compiler.
Update #3753
Update #4720
Fixes #10466
Change-Id: I0fd97d5f5ac527b45f49e2218d158a6e89951432
Reviewed-on: https://go-review.googlesource.com/8202
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2015-03-26 20:36:15 +00:00
|
|
|
func foo61(i *int) *int { // ERROR "leaking param: i to result ~r1 level=0$"
|
2014-09-24 19:20:03 +00:00
|
|
|
type S struct {
|
|
|
|
a, b *int
|
|
|
|
}
|
|
|
|
var s S
|
|
|
|
s.a = i
|
|
|
|
return s.b
|
|
|
|
}
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func foo61a(i *int) *int { // ERROR "foo61a i does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
type S struct {
|
|
|
|
a, b *int
|
|
|
|
}
|
|
|
|
var s S
|
|
|
|
s.a = i
|
|
|
|
return nil
|
|
|
|
}
|
|
|
|
|
|
|
|
// assigning to a struct field is like assigning to the struct but
|
|
|
|
// here this subtlety is lost, since s.a counts as an assignment to a
|
|
|
|
// track-losing dereference.
|
2015-02-19 19:00:11 +00:00
|
|
|
func foo62(i *int) *int { // ERROR "leaking param: i$"
|
2014-09-24 19:20:03 +00:00
|
|
|
type S struct {
|
|
|
|
a, b *int
|
|
|
|
}
|
2015-02-19 19:00:11 +00:00
|
|
|
s := new(S) // ERROR "foo62 new\(S\) does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
s.a = i
|
|
|
|
return nil // s.b
|
|
|
|
}
|
|
|
|
|
|
|
|
type M interface {
|
|
|
|
M()
|
|
|
|
}
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func foo63(m M) { // ERROR "foo63 m does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func foo64(m M) { // ERROR "leaking param: m$"
|
2014-09-24 19:20:03 +00:00
|
|
|
m.M()
|
|
|
|
}
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func foo64b(m M) { // ERROR "leaking param: m$"
|
2014-09-24 19:20:03 +00:00
|
|
|
defer m.M()
|
|
|
|
}
|
|
|
|
|
|
|
|
type MV int
|
|
|
|
|
|
|
|
func (MV) M() {}
|
|
|
|
|
|
|
|
func foo65() {
|
|
|
|
var mv MV
|
2015-02-19 19:00:11 +00:00
|
|
|
foo63(&mv) // ERROR "foo65 &mv does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
func foo66() {
|
2015-02-19 19:00:11 +00:00
|
|
|
var mv MV // ERROR "moved to heap: mv$"
|
|
|
|
foo64(&mv) // ERROR "&mv escapes to heap$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
func foo67() {
|
|
|
|
var mv MV
|
2015-02-19 19:00:11 +00:00
|
|
|
foo63(mv) // ERROR "foo67 mv does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
func foo68() {
|
|
|
|
var mv MV
|
2015-02-19 13:27:32 +00:00
|
|
|
// escapes but it's an int so irrelevant
|
2015-02-19 19:00:11 +00:00
|
|
|
foo64(mv) // ERROR "mv escapes to heap$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func foo69(m M) { // ERROR "leaking param: m$"
|
2014-09-24 19:20:03 +00:00
|
|
|
foo64(m)
|
|
|
|
}
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func foo70(mv1 *MV, m M) { // ERROR "leaking param: m$" "leaking param: mv1$"
|
|
|
|
m = mv1 // ERROR "mv1 escapes to heap$"
|
2014-09-24 19:20:03 +00:00
|
|
|
foo64(m)
|
|
|
|
}
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func foo71(x *int) []*int { // ERROR "leaking param: x$"
|
2014-09-24 19:20:03 +00:00
|
|
|
var y []*int
|
|
|
|
y = append(y, x)
|
|
|
|
return y
|
|
|
|
}
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func foo71a(x int) []*int { // ERROR "moved to heap: x$"
|
2014-09-24 19:20:03 +00:00
|
|
|
var y []*int
|
2015-02-19 19:00:11 +00:00
|
|
|
y = append(y, &x) // ERROR "&x escapes to heap$"
|
2014-09-24 19:20:03 +00:00
|
|
|
return y
|
|
|
|
}
|
|
|
|
|
|
|
|
func foo72() {
|
|
|
|
var x int
|
|
|
|
var y [1]*int
|
2015-02-19 19:00:11 +00:00
|
|
|
y[0] = &x // ERROR "foo72 &x does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
func foo72aa() [10]*int {
|
2015-02-19 19:00:11 +00:00
|
|
|
var x int // ERROR "moved to heap: x$"
|
2014-09-24 19:20:03 +00:00
|
|
|
var y [10]*int
|
2015-02-19 19:00:11 +00:00
|
|
|
y[0] = &x // ERROR "&x escapes to heap$"
|
2014-09-24 19:20:03 +00:00
|
|
|
return y
|
|
|
|
}
|
|
|
|
|
|
|
|
func foo72a() {
|
|
|
|
var y [10]*int
|
|
|
|
for i := 0; i < 10; i++ {
|
|
|
|
// escapes its scope
|
2015-02-19 19:00:11 +00:00
|
|
|
x := i // ERROR "moved to heap: x$"
|
|
|
|
y[i] = &x // ERROR "&x escapes to heap$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
return
|
|
|
|
}
|
|
|
|
|
|
|
|
func foo72b() [10]*int {
|
|
|
|
var y [10]*int
|
|
|
|
for i := 0; i < 10; i++ {
|
2015-02-19 19:00:11 +00:00
|
|
|
x := i // ERROR "moved to heap: x$"
|
|
|
|
y[i] = &x // ERROR "&x escapes to heap$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
return y
|
|
|
|
}
|
|
|
|
|
|
|
|
// issue 2145
|
|
|
|
func foo73() {
|
2015-02-19 19:00:11 +00:00
|
|
|
s := []int{3, 2, 1} // ERROR "foo73 \[\]int literal does not escape$"
|
2015-01-19 19:59:58 +00:00
|
|
|
for _, v := range s {
|
|
|
|
vv := v
|
|
|
|
// actually just escapes its scope
|
2015-02-19 19:00:11 +00:00
|
|
|
defer func() { // ERROR "func literal escapes to heap$"
|
2015-01-19 19:59:58 +00:00
|
|
|
println(vv)
|
|
|
|
}()
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
func foo731() {
|
2015-02-19 19:00:11 +00:00
|
|
|
s := []int{3, 2, 1} // ERROR "foo731 \[\]int literal does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
for _, v := range s {
|
2015-02-19 19:00:11 +00:00
|
|
|
vv := v // ERROR "moved to heap: vv$"
|
2014-09-24 19:20:03 +00:00
|
|
|
// actually just escapes its scope
|
2015-02-19 19:00:11 +00:00
|
|
|
defer func() { // ERROR "func literal escapes to heap$"
|
|
|
|
vv = 42 // ERROR "&vv escapes to heap$"
|
2015-01-19 19:59:58 +00:00
|
|
|
println(vv)
|
2014-09-24 19:20:03 +00:00
|
|
|
}()
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
func foo74() {
|
2015-02-19 19:00:11 +00:00
|
|
|
s := []int{3, 2, 1} // ERROR "foo74 \[\]int literal does not escape$"
|
2015-01-19 19:59:58 +00:00
|
|
|
for _, v := range s {
|
|
|
|
vv := v
|
|
|
|
// actually just escapes its scope
|
2015-02-19 19:00:11 +00:00
|
|
|
fn := func() { // ERROR "func literal escapes to heap$"
|
2015-01-19 19:59:58 +00:00
|
|
|
println(vv)
|
|
|
|
}
|
|
|
|
defer fn()
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
func foo74a() {
|
2015-02-19 19:00:11 +00:00
|
|
|
s := []int{3, 2, 1} // ERROR "foo74a \[\]int literal does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
for _, v := range s {
|
2015-02-19 19:00:11 +00:00
|
|
|
vv := v // ERROR "moved to heap: vv$"
|
2014-09-24 19:20:03 +00:00
|
|
|
// actually just escapes its scope
|
2015-02-19 19:00:11 +00:00
|
|
|
fn := func() { // ERROR "func literal escapes to heap$"
|
|
|
|
vv += 1 // ERROR "&vv escapes to heap$"
|
2015-01-19 19:59:58 +00:00
|
|
|
println(vv)
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
defer fn()
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
// issue 3975
|
|
|
|
func foo74b() {
|
2015-01-19 19:59:58 +00:00
|
|
|
var array [3]func()
|
2015-02-19 19:00:11 +00:00
|
|
|
s := []int{3, 2, 1} // ERROR "foo74b \[\]int literal does not escape$"
|
2015-01-19 19:59:58 +00:00
|
|
|
for i, v := range s {
|
|
|
|
vv := v
|
|
|
|
// actually just escapes its scope
|
2015-02-19 19:00:11 +00:00
|
|
|
array[i] = func() { // ERROR "func literal escapes to heap$"
|
2015-01-19 19:59:58 +00:00
|
|
|
println(vv)
|
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
func foo74c() {
|
2014-09-24 19:20:03 +00:00
|
|
|
var array [3]func()
|
2015-02-19 19:00:11 +00:00
|
|
|
s := []int{3, 2, 1} // ERROR "foo74c \[\]int literal does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
for i, v := range s {
|
2015-02-19 19:00:11 +00:00
|
|
|
vv := v // ERROR "moved to heap: vv$"
|
2014-09-24 19:20:03 +00:00
|
|
|
// actually just escapes its scope
|
2015-02-19 19:00:11 +00:00
|
|
|
array[i] = func() { // ERROR "func literal escapes to heap$"
|
2015-05-27 11:31:56 +00:00
|
|
|
println(&vv) // ERROR "&vv escapes to heap$" "foo74c.func1 &vv does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
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.${i}.prof ;
done
showed a 15% reduction in allocations performed by the compiler.
Update #3753
Update #4720
Fixes #10466
Change-Id: I0fd97d5f5ac527b45f49e2218d158a6e89951432
Reviewed-on: https://go-review.googlesource.com/8202
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2015-03-26 20:36:15 +00:00
|
|
|
func myprint(y *int, x ...interface{}) *int { // ERROR "leaking param: y to result ~r2 level=0$" "myprint x does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
return y
|
|
|
|
}
|
|
|
|
|
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.${i}.prof ;
done
showed a 15% reduction in allocations performed by the compiler.
Update #3753
Update #4720
Fixes #10466
Change-Id: I0fd97d5f5ac527b45f49e2218d158a6e89951432
Reviewed-on: https://go-review.googlesource.com/8202
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2015-03-26 20:36:15 +00:00
|
|
|
func myprint1(y *int, x ...interface{}) *interface{} { // ERROR "leaking param: x to result ~r2 level=0$" "myprint1 y does not escape$"
|
2015-02-19 19:00:11 +00:00
|
|
|
return &x[0] // ERROR "&x\[0\] escapes to heap$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func foo75(z *int) { // ERROR "foo75 z does not escape$"
|
|
|
|
myprint(z, 1, 2, 3) // ERROR "1 escapes to heap$" "2 escapes to heap$" "3 escapes to heap$" "foo75 ... argument does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func foo75a(z *int) { // ERROR "foo75a z does not escape$"
|
|
|
|
myprint1(z, 1, 2, 3) // ERROR "1 escapes to heap$" "2 escapes to heap$" "3 escapes to heap$" "foo75a ... argument does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func foo75esc(z *int) { // ERROR "leaking param: z$"
|
|
|
|
gxx = myprint(z, 1, 2, 3) // ERROR "1 escapes to heap$" "2 escapes to heap$" "3 escapes to heap$" "foo75esc ... argument does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func foo75aesc(z *int) { // ERROR "foo75aesc z does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
var ppi **interface{} // assignments to pointer dereferences lose track
|
2015-02-19 19:00:11 +00:00
|
|
|
*ppi = myprint1(z, 1, 2, 3) // ERROR "... argument escapes to heap$" "1 escapes to heap$" "2 escapes to heap$" "3 escapes to heap$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func foo75aesc1(z *int) { // ERROR "foo75aesc1 z does not escape$"
|
|
|
|
sink = myprint1(z, 1, 2, 3) // ERROR "... argument escapes to heap$" "1 escapes to heap$" "2 escapes to heap$" "3 escapes to heap$" "myprint1\(z, 1, 2, 3\) escapes to heap$"
|
2015-02-19 14:54:55 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
// BAD: z does not escape here
|
2015-02-19 19:00:11 +00:00
|
|
|
func foo76(z *int) { // ERROR "leaking param: z$"
|
|
|
|
myprint(nil, z) // ERROR "foo76 ... argument does not escape$" "z escapes to heap$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
|
2015-02-19 14:54:55 +00:00
|
|
|
// BAD: z does not escape here
|
2015-02-19 19:00:11 +00:00
|
|
|
func foo76a(z *int) { // ERROR "leaking param: z$"
|
|
|
|
myprint1(nil, z) // ERROR "foo76a ... argument does not escape$" "z escapes to heap$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
func foo76b() {
|
2015-02-19 19:00:11 +00:00
|
|
|
myprint(nil, 1, 2, 3) // ERROR "1 escapes to heap$" "2 escapes to heap$" "3 escapes to heap$" "foo76b ... argument does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
func foo76c() {
|
2015-02-19 19:00:11 +00:00
|
|
|
myprint1(nil, 1, 2, 3) // ERROR "1 escapes to heap$" "2 escapes to heap$" "3 escapes to heap$" "foo76c ... argument does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
func foo76d() {
|
2015-02-19 19:00:11 +00:00
|
|
|
defer myprint(nil, 1, 2, 3) // ERROR "1 escapes to heap$" "2 escapes to heap$" "3 escapes to heap$" "foo76d ... argument does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
func foo76e() {
|
2015-02-19 19:00:11 +00:00
|
|
|
defer myprint1(nil, 1, 2, 3) // ERROR "1 escapes to heap$" "2 escapes to heap$" "3 escapes to heap$" "foo76e ... argument does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
func foo76f() {
|
|
|
|
for {
|
|
|
|
// TODO: This one really only escapes its scope, but we don't distinguish yet.
|
2015-02-19 19:00:11 +00:00
|
|
|
defer myprint(nil, 1, 2, 3) // ERROR "... argument escapes to heap$" "1 escapes to heap$" "2 escapes to heap$" "3 escapes to heap$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
func foo76g() {
|
|
|
|
for {
|
2015-02-19 19:00:11 +00:00
|
|
|
defer myprint1(nil, 1, 2, 3) // ERROR "... argument escapes to heap$" "1 escapes to heap$" "2 escapes to heap$" "3 escapes to heap$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func foo77(z []interface{}) { // ERROR "foo77 z does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
myprint(nil, z...) // z does not escape
|
|
|
|
}
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func foo77a(z []interface{}) { // ERROR "foo77a z does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
myprint1(nil, z...)
|
|
|
|
}
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func foo77b(z []interface{}) { // ERROR "leaking param: z$"
|
2014-09-24 19:20:03 +00:00
|
|
|
var ppi **interface{}
|
|
|
|
*ppi = myprint1(nil, z...)
|
|
|
|
}
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func foo77c(z []interface{}) { // ERROR "leaking param: z$"
|
|
|
|
sink = myprint1(nil, z...) // ERROR "myprint1\(nil, z...\) escapes to heap$"
|
2015-02-19 14:54:55 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
func dotdotdot() {
|
|
|
|
// BAD: i should not escape here
|
2015-02-19 19:00:11 +00:00
|
|
|
i := 0 // ERROR "moved to heap: i$"
|
|
|
|
myprint(nil, &i) // ERROR "&i escapes to heap$" "dotdotdot ... argument does not escape$"
|
2015-02-19 14:54:55 +00:00
|
|
|
|
|
|
|
// BAD: j should not escape here
|
2015-02-19 19:00:11 +00:00
|
|
|
j := 0 // ERROR "moved to heap: j$"
|
|
|
|
myprint1(nil, &j) // ERROR "&j escapes to heap$" "dotdotdot ... argument does not escape$"
|
2015-02-19 14:54:55 +00:00
|
|
|
}
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func foo78(z int) *int { // ERROR "moved to heap: z$"
|
|
|
|
return &z // ERROR "&z escapes to heap$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func foo78a(z int) *int { // ERROR "moved to heap: z$"
|
|
|
|
y := &z // ERROR "&z escapes to heap$"
|
|
|
|
x := &y // ERROR "foo78a &y does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
return *x // really return y
|
|
|
|
}
|
|
|
|
|
|
|
|
func foo79() *int {
|
2015-02-19 19:00:11 +00:00
|
|
|
return new(int) // ERROR "new\(int\) escapes to heap$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
func foo80() *int {
|
|
|
|
var z *int
|
|
|
|
for {
|
|
|
|
// Really just escapes its scope but we don't distinguish
|
2015-02-19 19:00:11 +00:00
|
|
|
z = new(int) // ERROR "new\(int\) escapes to heap$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
_ = z
|
|
|
|
return nil
|
|
|
|
}
|
|
|
|
|
|
|
|
func foo81() *int {
|
|
|
|
for {
|
2015-02-19 19:00:11 +00:00
|
|
|
z := new(int) // ERROR "foo81 new\(int\) does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
_ = z
|
|
|
|
}
|
|
|
|
return nil
|
|
|
|
}
|
|
|
|
|
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.${i}.prof ;
done
showed a 15% reduction in allocations performed by the compiler.
Update #3753
Update #4720
Fixes #10466
Change-Id: I0fd97d5f5ac527b45f49e2218d158a6e89951432
Reviewed-on: https://go-review.googlesource.com/8202
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2015-03-26 20:36:15 +00:00
|
|
|
func tee(p *int) (x, y *int) { return p, p } // ERROR "leaking param: p to result x level=0$" "leaking param: p to result y level=0$"
|
2014-09-24 19:20:03 +00:00
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func noop(x, y *int) {} // ERROR "noop x does not escape$" "noop y does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
|
|
|
|
func foo82() {
|
2015-02-19 19:00:11 +00:00
|
|
|
var x, y, z int // ERROR "moved to heap: x$" "moved to heap: y$" "moved to heap: z$"
|
|
|
|
go noop(tee(&z)) // ERROR "&z escapes to heap$"
|
|
|
|
go noop(&x, &y) // ERROR "&x escapes to heap$" "&y escapes to heap$"
|
2014-09-24 19:20:03 +00:00
|
|
|
for {
|
2015-02-19 19:00:11 +00:00
|
|
|
var u, v, w int // ERROR "moved to heap: u$" "moved to heap: v$" "moved to heap: w$"
|
|
|
|
defer noop(tee(&u)) // ERROR "&u escapes to heap$"
|
|
|
|
defer noop(&v, &w) // ERROR "&v escapes to heap$" "&w escapes to heap$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
type Fooer interface {
|
|
|
|
Foo()
|
|
|
|
}
|
|
|
|
|
|
|
|
type LimitedFooer struct {
|
|
|
|
Fooer
|
|
|
|
N int64
|
|
|
|
}
|
|
|
|
|
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.${i}.prof ;
done
showed a 15% reduction in allocations performed by the compiler.
Update #3753
Update #4720
Fixes #10466
Change-Id: I0fd97d5f5ac527b45f49e2218d158a6e89951432
Reviewed-on: https://go-review.googlesource.com/8202
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2015-03-26 20:36:15 +00:00
|
|
|
func LimitFooer(r Fooer, n int64) Fooer { // ERROR "leaking param: r to result ~r2 level=-1$"
|
2015-02-19 19:00:11 +00:00
|
|
|
return &LimitedFooer{r, n} // ERROR "&LimitedFooer literal escapes to heap$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func foo90(x *int) map[*int]*int { // ERROR "leaking param: x$"
|
|
|
|
return map[*int]*int{nil: x} // ERROR "map\[\*int\]\*int literal escapes to heap$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func foo91(x *int) map[*int]*int { // ERROR "leaking param: x$"
|
|
|
|
return map[*int]*int{x: nil} // ERROR "map\[\*int\]\*int literal escapes to heap$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
|
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.${i}.prof ;
done
showed a 15% reduction in allocations performed by the compiler.
Update #3753
Update #4720
Fixes #10466
Change-Id: I0fd97d5f5ac527b45f49e2218d158a6e89951432
Reviewed-on: https://go-review.googlesource.com/8202
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2015-03-26 20:36:15 +00:00
|
|
|
func foo92(x *int) [2]*int { // ERROR "leaking param: x to result ~r1 level=0$"
|
2014-09-24 19:20:03 +00:00
|
|
|
return [2]*int{x, nil}
|
|
|
|
}
|
|
|
|
|
|
|
|
// does not leak c
|
2015-02-19 19:00:11 +00:00
|
|
|
func foo93(c chan *int) *int { // ERROR "foo93 c does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
for v := range c {
|
|
|
|
return v
|
|
|
|
}
|
|
|
|
return nil
|
|
|
|
}
|
|
|
|
|
|
|
|
// does not leak m
|
2015-05-15 16:19:07 +00:00
|
|
|
func foo94(m map[*int]*int, b bool) *int { // ERROR "leaking param: m to result ~r2 level=1"
|
2014-09-24 19:20:03 +00:00
|
|
|
for k, v := range m {
|
|
|
|
if b {
|
|
|
|
return k
|
|
|
|
}
|
|
|
|
return v
|
|
|
|
}
|
|
|
|
return nil
|
|
|
|
}
|
|
|
|
|
|
|
|
// does leak x
|
2015-02-19 19:00:11 +00:00
|
|
|
func foo95(m map[*int]*int, x *int) { // ERROR "foo95 m does not escape$" "leaking param: x$"
|
2014-09-24 19:20:03 +00:00
|
|
|
m[x] = x
|
|
|
|
}
|
|
|
|
|
2015-05-15 16:19:07 +00:00
|
|
|
// does not leak m but does leak content
|
|
|
|
func foo96(m []*int) *int { // ERROR "leaking param: m to result ~r1 level=1"
|
2014-09-24 19:20:03 +00:00
|
|
|
return m[0]
|
|
|
|
}
|
|
|
|
|
|
|
|
// does leak m
|
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.${i}.prof ;
done
showed a 15% reduction in allocations performed by the compiler.
Update #3753
Update #4720
Fixes #10466
Change-Id: I0fd97d5f5ac527b45f49e2218d158a6e89951432
Reviewed-on: https://go-review.googlesource.com/8202
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2015-03-26 20:36:15 +00:00
|
|
|
func foo97(m [1]*int) *int { // ERROR "leaking param: m to result ~r1 level=0$"
|
2014-09-24 19:20:03 +00:00
|
|
|
return m[0]
|
|
|
|
}
|
|
|
|
|
|
|
|
// does not leak m
|
2015-02-19 19:00:11 +00:00
|
|
|
func foo98(m map[int]*int) *int { // ERROR "foo98 m does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
return m[0]
|
|
|
|
}
|
|
|
|
|
|
|
|
// does leak m
|
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.${i}.prof ;
done
showed a 15% reduction in allocations performed by the compiler.
Update #3753
Update #4720
Fixes #10466
Change-Id: I0fd97d5f5ac527b45f49e2218d158a6e89951432
Reviewed-on: https://go-review.googlesource.com/8202
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2015-03-26 20:36:15 +00:00
|
|
|
func foo99(m *[1]*int) []*int { // ERROR "leaking param: m to result ~r1 level=0$"
|
2014-09-24 19:20:03 +00:00
|
|
|
return m[:]
|
|
|
|
}
|
|
|
|
|
|
|
|
// does not leak m
|
2015-05-15 16:19:07 +00:00
|
|
|
func foo100(m []*int) *int { // ERROR "leaking param: m to result ~r1 level=1"
|
2014-09-24 19:20:03 +00:00
|
|
|
for _, v := range m {
|
|
|
|
return v
|
|
|
|
}
|
|
|
|
return nil
|
|
|
|
}
|
|
|
|
|
|
|
|
// does leak m
|
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>
2015-03-26 20:36:15 +00:00
|
|
|
func foo101(m [1]*int) *int { // ERROR "leaking param: m to result ~r1 level=0$"
|
2014-09-24 19:20:03 +00:00
|
|
|
for _, v := range m {
|
|
|
|
return v
|
|
|
|
}
|
|
|
|
return nil
|
|
|
|
}
|
|
|
|
|
|
|
|
// does not leak m
|
2015-02-19 19:00:11 +00:00
|
|
|
func foo101a(m [1]*int) *int { // ERROR "foo101a m does not escape$"
|
|
|
|
for i := range m { // ERROR "moved to heap: i$"
|
|
|
|
return &i // ERROR "&i escapes to heap$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
return nil
|
|
|
|
}
|
|
|
|
|
|
|
|
// does leak x
|
2015-02-19 19:00:11 +00:00
|
|
|
func foo102(m []*int, x *int) { // ERROR "foo102 m does not escape$" "leaking param: x$"
|
2014-09-24 19:20:03 +00:00
|
|
|
m[0] = x
|
|
|
|
}
|
|
|
|
|
|
|
|
// does not leak x
|
2015-02-19 19:00:11 +00:00
|
|
|
func foo103(m [1]*int, x *int) { // ERROR "foo103 m does not escape$" "foo103 x does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
m[0] = x
|
|
|
|
}
|
|
|
|
|
|
|
|
var y []*int
|
|
|
|
|
2015-06-24 21:31:57 +00:00
|
|
|
// does not leak x but does leak content
|
|
|
|
func foo104(x []*int) { // ERROR "leaking param content: x"
|
2014-09-24 19:20:03 +00:00
|
|
|
copy(y, x)
|
|
|
|
}
|
|
|
|
|
2015-05-15 16:19:07 +00:00
|
|
|
// does not leak x but does leak content
|
|
|
|
func foo105(x []*int) { // ERROR "leaking param content: x"
|
2014-09-24 19:20:03 +00:00
|
|
|
_ = append(y, x...)
|
|
|
|
}
|
|
|
|
|
|
|
|
// does leak x
|
2015-02-19 19:00:11 +00:00
|
|
|
func foo106(x *int) { // ERROR "leaking param: x$"
|
2014-09-24 19:20:03 +00:00
|
|
|
_ = append(y, x)
|
|
|
|
}
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func foo107(x *int) map[*int]*int { // ERROR "leaking param: x$"
|
|
|
|
return map[*int]*int{x: nil} // ERROR "map\[\*int\]\*int literal escapes to heap$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func foo108(x *int) map[*int]*int { // ERROR "leaking param: x$"
|
|
|
|
return map[*int]*int{nil: x} // ERROR "map\[\*int\]\*int literal escapes to heap$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func foo109(x *int) *int { // ERROR "leaking param: x$"
|
|
|
|
m := map[*int]*int{x: nil} // ERROR "foo109 map\[\*int\]\*int literal does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
for k, _ := range m {
|
|
|
|
return k
|
|
|
|
}
|
|
|
|
return nil
|
|
|
|
}
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func foo110(x *int) *int { // ERROR "leaking param: x$"
|
|
|
|
m := map[*int]*int{nil: x} // ERROR "foo110 map\[\*int\]\*int literal does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
return m[nil]
|
|
|
|
}
|
|
|
|
|
2015-05-15 16:19:07 +00:00
|
|
|
func foo111(x *int) *int { // ERROR "leaking param: x to result ~r1 level=0"
|
2015-02-19 19:00:11 +00:00
|
|
|
m := []*int{x} // ERROR "foo111 \[\]\*int literal does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
return m[0]
|
|
|
|
}
|
|
|
|
|
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.${i}.prof ;
done
showed a 15% reduction in allocations performed by the compiler.
Update #3753
Update #4720
Fixes #10466
Change-Id: I0fd97d5f5ac527b45f49e2218d158a6e89951432
Reviewed-on: https://go-review.googlesource.com/8202
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2015-03-26 20:36:15 +00:00
|
|
|
func foo112(x *int) *int { // ERROR "leaking param: x to result ~r1 level=0$"
|
2014-09-24 19:20:03 +00:00
|
|
|
m := [1]*int{x}
|
|
|
|
return m[0]
|
|
|
|
}
|
|
|
|
|
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>
2015-03-26 20:36:15 +00:00
|
|
|
func foo113(x *int) *int { // ERROR "leaking param: x to result ~r1 level=0$"
|
2014-09-24 19:20:03 +00:00
|
|
|
m := Bar{ii: x}
|
|
|
|
return m.ii
|
|
|
|
}
|
|
|
|
|
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.${i}.prof ;
done
showed a 15% reduction in allocations performed by the compiler.
Update #3753
Update #4720
Fixes #10466
Change-Id: I0fd97d5f5ac527b45f49e2218d158a6e89951432
Reviewed-on: https://go-review.googlesource.com/8202
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2015-03-26 20:36:15 +00:00
|
|
|
func foo114(x *int) *int { // ERROR "leaking param: x to result ~r1 level=0$"
|
2015-02-19 19:00:11 +00:00
|
|
|
m := &Bar{ii: x} // ERROR "foo114 &Bar literal does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
return m.ii
|
|
|
|
}
|
|
|
|
|
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.${i}.prof ;
done
showed a 15% reduction in allocations performed by the compiler.
Update #3753
Update #4720
Fixes #10466
Change-Id: I0fd97d5f5ac527b45f49e2218d158a6e89951432
Reviewed-on: https://go-review.googlesource.com/8202
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2015-03-26 20:36:15 +00:00
|
|
|
func foo115(x *int) *int { // ERROR "leaking param: x to result ~r1 level=0$"
|
2014-09-24 19:20:03 +00:00
|
|
|
return (*int)(unsafe.Pointer(uintptr(unsafe.Pointer(x)) + 1))
|
|
|
|
}
|
|
|
|
|
|
|
|
func foo116(b bool) *int {
|
|
|
|
if b {
|
2015-02-19 19:00:11 +00:00
|
|
|
x := 1 // ERROR "moved to heap: x$"
|
|
|
|
return &x // ERROR "&x escapes to heap$"
|
2014-09-24 19:20:03 +00:00
|
|
|
} else {
|
2015-02-19 19:00:11 +00:00
|
|
|
y := 1 // ERROR "moved to heap: y$"
|
|
|
|
return &y // ERROR "&y escapes to heap$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
return nil
|
|
|
|
}
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func foo117(unknown func(interface{})) { // ERROR "foo117 unknown does not escape$"
|
|
|
|
x := 1 // ERROR "moved to heap: x$"
|
|
|
|
unknown(&x) // ERROR "&x escapes to heap$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func foo118(unknown func(*int)) { // ERROR "foo118 unknown does not escape$"
|
|
|
|
x := 1 // ERROR "moved to heap: x$"
|
|
|
|
unknown(&x) // ERROR "&x escapes to heap$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
func external(*int)
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func foo119(x *int) { // ERROR "leaking param: x$"
|
2014-09-24 19:20:03 +00:00
|
|
|
external(x)
|
|
|
|
}
|
|
|
|
|
|
|
|
func foo120() {
|
|
|
|
// formerly exponential time analysis
|
|
|
|
L1:
|
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|
|
L2:
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L3:
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L4:
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L5:
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L6:
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L7:
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L8:
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L9:
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L10:
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L11:
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L12:
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L13:
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L14:
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L15:
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L16:
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L17:
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L18:
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L19:
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L20:
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L21:
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L22:
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L23:
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L24:
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L25:
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L26:
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L27:
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L28:
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L29:
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L30:
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L31:
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L32:
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L33:
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L34:
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L35:
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L36:
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L37:
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L38:
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L39:
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L40:
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L41:
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L42:
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L43:
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L44:
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L45:
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L46:
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L47:
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L48:
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L49:
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L50:
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|
L51:
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L52:
|
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|
|
L53:
|
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|
|
L54:
|
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|
|
L55:
|
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L56:
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|
L57:
|
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|
|
L58:
|
|
|
|
L59:
|
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|
|
L60:
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|
|
|
L61:
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|
|
L62:
|
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|
|
L63:
|
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|
|
L64:
|
|
|
|
L65:
|
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|
|
L66:
|
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|
|
L67:
|
|
|
|
L68:
|
|
|
|
L69:
|
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|
|
L70:
|
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|
|
L71:
|
|
|
|
L72:
|
|
|
|
L73:
|
|
|
|
L74:
|
|
|
|
L75:
|
|
|
|
L76:
|
|
|
|
L77:
|
|
|
|
L78:
|
|
|
|
L79:
|
|
|
|
L80:
|
|
|
|
L81:
|
|
|
|
L82:
|
|
|
|
L83:
|
|
|
|
L84:
|
|
|
|
L85:
|
|
|
|
L86:
|
|
|
|
L87:
|
|
|
|
L88:
|
|
|
|
L89:
|
|
|
|
L90:
|
|
|
|
L91:
|
|
|
|
L92:
|
|
|
|
L93:
|
|
|
|
L94:
|
|
|
|
L95:
|
|
|
|
L96:
|
|
|
|
L97:
|
|
|
|
L98:
|
|
|
|
L99:
|
|
|
|
L100:
|
|
|
|
// use the labels to silence compiler errors
|
|
|
|
goto L1
|
|
|
|
goto L2
|
|
|
|
goto L3
|
|
|
|
goto L4
|
|
|
|
goto L5
|
|
|
|
goto L6
|
|
|
|
goto L7
|
|
|
|
goto L8
|
|
|
|
goto L9
|
|
|
|
goto L10
|
|
|
|
goto L11
|
|
|
|
goto L12
|
|
|
|
goto L13
|
|
|
|
goto L14
|
|
|
|
goto L15
|
|
|
|
goto L16
|
|
|
|
goto L17
|
|
|
|
goto L18
|
|
|
|
goto L19
|
|
|
|
goto L20
|
|
|
|
goto L21
|
|
|
|
goto L22
|
|
|
|
goto L23
|
|
|
|
goto L24
|
|
|
|
goto L25
|
|
|
|
goto L26
|
|
|
|
goto L27
|
|
|
|
goto L28
|
|
|
|
goto L29
|
|
|
|
goto L30
|
|
|
|
goto L31
|
|
|
|
goto L32
|
|
|
|
goto L33
|
|
|
|
goto L34
|
|
|
|
goto L35
|
|
|
|
goto L36
|
|
|
|
goto L37
|
|
|
|
goto L38
|
|
|
|
goto L39
|
|
|
|
goto L40
|
|
|
|
goto L41
|
|
|
|
goto L42
|
|
|
|
goto L43
|
|
|
|
goto L44
|
|
|
|
goto L45
|
|
|
|
goto L46
|
|
|
|
goto L47
|
|
|
|
goto L48
|
|
|
|
goto L49
|
|
|
|
goto L50
|
|
|
|
goto L51
|
|
|
|
goto L52
|
|
|
|
goto L53
|
|
|
|
goto L54
|
|
|
|
goto L55
|
|
|
|
goto L56
|
|
|
|
goto L57
|
|
|
|
goto L58
|
|
|
|
goto L59
|
|
|
|
goto L60
|
|
|
|
goto L61
|
|
|
|
goto L62
|
|
|
|
goto L63
|
|
|
|
goto L64
|
|
|
|
goto L65
|
|
|
|
goto L66
|
|
|
|
goto L67
|
|
|
|
goto L68
|
|
|
|
goto L69
|
|
|
|
goto L70
|
|
|
|
goto L71
|
|
|
|
goto L72
|
|
|
|
goto L73
|
|
|
|
goto L74
|
|
|
|
goto L75
|
|
|
|
goto L76
|
|
|
|
goto L77
|
|
|
|
goto L78
|
|
|
|
goto L79
|
|
|
|
goto L80
|
|
|
|
goto L81
|
|
|
|
goto L82
|
|
|
|
goto L83
|
|
|
|
goto L84
|
|
|
|
goto L85
|
|
|
|
goto L86
|
|
|
|
goto L87
|
|
|
|
goto L88
|
|
|
|
goto L89
|
|
|
|
goto L90
|
|
|
|
goto L91
|
|
|
|
goto L92
|
|
|
|
goto L93
|
|
|
|
goto L94
|
|
|
|
goto L95
|
|
|
|
goto L96
|
|
|
|
goto L97
|
|
|
|
goto L98
|
|
|
|
goto L99
|
|
|
|
goto L100
|
|
|
|
}
|
|
|
|
|
|
|
|
func foo121() {
|
|
|
|
for i := 0; i < 10; i++ {
|
2015-02-19 19:00:11 +00:00
|
|
|
defer myprint(nil, i) // ERROR "... argument escapes to heap$" "i escapes to heap$"
|
|
|
|
go myprint(nil, i) // ERROR "... argument escapes to heap$" "i escapes to heap$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
// same as foo121 but check across import
|
|
|
|
func foo121b() {
|
|
|
|
for i := 0; i < 10; i++ {
|
2015-02-19 19:00:11 +00:00
|
|
|
defer fmt.Printf("%d", i) // ERROR "... argument escapes to heap$" "i escapes to heap$"
|
|
|
|
go fmt.Printf("%d", i) // ERROR "... argument escapes to heap$" "i escapes to heap$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
// a harmless forward jump
|
|
|
|
func foo122() {
|
|
|
|
var i *int
|
|
|
|
|
|
|
|
goto L1
|
|
|
|
L1:
|
2015-02-19 19:00:11 +00:00
|
|
|
i = new(int) // ERROR "foo122 new\(int\) does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
_ = i
|
|
|
|
}
|
|
|
|
|
|
|
|
// a backward jump, increases loopdepth
|
|
|
|
func foo123() {
|
|
|
|
var i *int
|
|
|
|
|
|
|
|
L1:
|
2015-02-19 19:00:11 +00:00
|
|
|
i = new(int) // ERROR "new\(int\) escapes to heap$"
|
2014-09-24 19:20:03 +00:00
|
|
|
|
|
|
|
goto L1
|
|
|
|
_ = i
|
|
|
|
}
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func foo124(x **int) { // ERROR "foo124 x does not escape$"
|
|
|
|
var i int // ERROR "moved to heap: i$"
|
|
|
|
p := &i // ERROR "&i escapes to heap$"
|
|
|
|
func() { // ERROR "foo124 func literal does not escape$"
|
|
|
|
*x = p // ERROR "leaking closure reference p$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}()
|
|
|
|
}
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func foo125(ch chan *int) { // ERROR "foo125 ch does not escape$"
|
|
|
|
var i int // ERROR "moved to heap: i$"
|
|
|
|
p := &i // ERROR "&i escapes to heap$"
|
|
|
|
func() { // ERROR "foo125 func literal does not escape$"
|
|
|
|
ch <- p // ERROR "leaking closure reference p$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}()
|
|
|
|
}
|
|
|
|
|
|
|
|
func foo126() {
|
|
|
|
var px *int // loopdepth 0
|
|
|
|
for {
|
|
|
|
// loopdepth 1
|
2015-02-19 19:00:11 +00:00
|
|
|
var i int // ERROR "moved to heap: i$"
|
|
|
|
func() { // ERROR "foo126 func literal does not escape$"
|
|
|
|
px = &i // ERROR "&i escapes to heap$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}()
|
|
|
|
}
|
|
|
|
_ = px
|
|
|
|
}
|
|
|
|
|
|
|
|
var px *int
|
|
|
|
|
|
|
|
func foo127() {
|
2015-02-19 19:00:11 +00:00
|
|
|
var i int // ERROR "moved to heap: i$"
|
|
|
|
p := &i // ERROR "&i escapes to heap$"
|
2014-09-24 19:20:03 +00:00
|
|
|
q := p
|
|
|
|
px = q
|
|
|
|
}
|
|
|
|
|
|
|
|
func foo128() {
|
|
|
|
var i int
|
2015-02-19 19:00:11 +00:00
|
|
|
p := &i // ERROR "foo128 &i does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
q := p
|
|
|
|
_ = q
|
|
|
|
}
|
|
|
|
|
|
|
|
func foo129() {
|
2015-02-19 19:00:11 +00:00
|
|
|
var i int // ERROR "moved to heap: i$"
|
|
|
|
p := &i // ERROR "&i escapes to heap$"
|
|
|
|
func() { // ERROR "foo129 func literal does not escape$"
|
|
|
|
q := p // ERROR "leaking closure reference p$"
|
2015-05-27 11:31:56 +00:00
|
|
|
func() { // ERROR "foo129.func1 func literal does not escape$"
|
2015-02-19 19:00:11 +00:00
|
|
|
r := q // ERROR "leaking closure reference q$"
|
2014-09-24 19:20:03 +00:00
|
|
|
px = r
|
|
|
|
}()
|
|
|
|
}()
|
|
|
|
}
|
|
|
|
|
|
|
|
func foo130() {
|
|
|
|
for {
|
2015-02-19 19:00:11 +00:00
|
|
|
var i int // ERROR "moved to heap: i$"
|
|
|
|
func() { // ERROR "foo130 func literal does not escape$"
|
|
|
|
px = &i // ERROR "&i escapes to heap$" "leaking closure reference i$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}()
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
func foo131() {
|
2015-02-19 19:00:11 +00:00
|
|
|
var i int // ERROR "moved to heap: i$"
|
|
|
|
func() { // ERROR "foo131 func literal does not escape$"
|
|
|
|
px = &i // ERROR "&i escapes to heap$" "leaking closure reference i$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}()
|
|
|
|
}
|
|
|
|
|
|
|
|
func foo132() {
|
2015-02-19 19:00:11 +00:00
|
|
|
var i int // ERROR "moved to heap: i$"
|
|
|
|
go func() { // ERROR "func literal escapes to heap$"
|
|
|
|
px = &i // ERROR "&i escapes to heap$" "leaking closure reference i$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}()
|
|
|
|
}
|
|
|
|
|
|
|
|
func foo133() {
|
2015-02-19 19:00:11 +00:00
|
|
|
var i int // ERROR "moved to heap: i$"
|
|
|
|
defer func() { // ERROR "foo133 func literal does not escape$"
|
|
|
|
px = &i // ERROR "&i escapes to heap$" "leaking closure reference i$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}()
|
|
|
|
}
|
|
|
|
|
|
|
|
func foo134() {
|
|
|
|
var i int
|
2015-02-19 19:00:11 +00:00
|
|
|
p := &i // ERROR "foo134 &i does not escape$"
|
|
|
|
func() { // ERROR "foo134 func literal does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
q := p
|
2015-05-27 11:31:56 +00:00
|
|
|
func() { // ERROR "foo134.func1 func literal does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
r := q
|
|
|
|
_ = r
|
|
|
|
}()
|
|
|
|
}()
|
|
|
|
}
|
|
|
|
|
|
|
|
func foo135() {
|
2015-02-19 19:00:11 +00:00
|
|
|
var i int // ERROR "moved to heap: i$"
|
|
|
|
p := &i // ERROR "&i escapes to heap$"
|
|
|
|
go func() { // ERROR "func literal escapes to heap$"
|
2015-01-19 19:59:58 +00:00
|
|
|
q := p
|
2015-05-27 11:31:56 +00:00
|
|
|
func() { // ERROR "foo135.func1 func literal does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
r := q
|
|
|
|
_ = r
|
|
|
|
}()
|
|
|
|
}()
|
|
|
|
}
|
|
|
|
|
|
|
|
func foo136() {
|
2015-02-19 19:00:11 +00:00
|
|
|
var i int // ERROR "moved to heap: i$"
|
|
|
|
p := &i // ERROR "&i escapes to heap$"
|
|
|
|
go func() { // ERROR "func literal escapes to heap$"
|
|
|
|
q := p // ERROR "leaking closure reference p$"
|
2015-05-27 11:31:56 +00:00
|
|
|
func() { // ERROR "foo136.func1 func literal does not escape$"
|
2015-02-19 19:00:11 +00:00
|
|
|
r := q // ERROR "leaking closure reference q$"
|
2014-09-24 19:20:03 +00:00
|
|
|
px = r
|
|
|
|
}()
|
|
|
|
}()
|
|
|
|
}
|
|
|
|
|
|
|
|
func foo137() {
|
2015-02-19 19:00:11 +00:00
|
|
|
var i int // ERROR "moved to heap: i$"
|
|
|
|
p := &i // ERROR "&i escapes to heap$"
|
|
|
|
func() { // ERROR "foo137 func literal does not escape$"
|
|
|
|
q := p // ERROR "leaking closure reference p$"
|
|
|
|
go func() { // ERROR "func literal escapes to heap$"
|
2015-01-19 19:59:58 +00:00
|
|
|
r := q
|
2014-09-24 19:20:03 +00:00
|
|
|
_ = r
|
|
|
|
}()
|
|
|
|
}()
|
|
|
|
}
|
|
|
|
|
|
|
|
func foo138() *byte {
|
|
|
|
type T struct {
|
|
|
|
x [1]byte
|
|
|
|
}
|
2015-02-19 19:00:11 +00:00
|
|
|
t := new(T) // ERROR "new\(T\) escapes to heap$"
|
|
|
|
return &t.x[0] // ERROR "&t.x\[0\] escapes to heap$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
func foo139() *byte {
|
|
|
|
type T struct {
|
|
|
|
x struct {
|
|
|
|
y byte
|
|
|
|
}
|
|
|
|
}
|
2015-02-19 19:00:11 +00:00
|
|
|
t := new(T) // ERROR "new\(T\) escapes to heap$"
|
|
|
|
return &t.x.y // ERROR "&t.x.y escapes to heap$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
// issue 4751
|
|
|
|
func foo140() interface{} {
|
|
|
|
type T struct {
|
|
|
|
X string
|
|
|
|
}
|
|
|
|
type U struct {
|
|
|
|
X string
|
|
|
|
T *T
|
|
|
|
}
|
2015-02-19 19:00:11 +00:00
|
|
|
t := &T{} // ERROR "&T literal escapes to heap$"
|
|
|
|
return U{ // ERROR "U literal escapes to heap$"
|
2014-09-24 19:20:03 +00:00
|
|
|
X: t.X,
|
|
|
|
T: t,
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
//go:noescape
|
|
|
|
|
|
|
|
func F1([]byte)
|
|
|
|
|
|
|
|
func F2([]byte)
|
|
|
|
|
|
|
|
//go:noescape
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func F3(x []byte) // ERROR "F3 x does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
|
|
|
|
func F4(x []byte)
|
|
|
|
|
|
|
|
func G() {
|
|
|
|
var buf1 [10]byte
|
2015-02-19 19:00:11 +00:00
|
|
|
F1(buf1[:]) // ERROR "G buf1 does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
var buf2 [10]byte // ERROR "moved to heap: buf2$"
|
|
|
|
F2(buf2[:]) // ERROR "buf2 escapes to heap$"
|
2014-09-24 19:20:03 +00:00
|
|
|
|
|
|
|
var buf3 [10]byte
|
2015-02-19 19:00:11 +00:00
|
|
|
F3(buf3[:]) // ERROR "G buf3 does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
var buf4 [10]byte // ERROR "moved to heap: buf4$"
|
|
|
|
F4(buf4[:]) // ERROR "buf4 escapes to heap$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
type Tm struct {
|
|
|
|
x int
|
|
|
|
}
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func (t *Tm) M() { // ERROR "\(\*Tm\).M t does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
func foo141() {
|
|
|
|
var f func()
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
t := new(Tm) // ERROR "new\(Tm\) escapes to heap$"
|
|
|
|
f = t.M // ERROR "foo141 t.M does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
_ = f
|
|
|
|
}
|
|
|
|
|
|
|
|
var gf func()
|
|
|
|
|
|
|
|
func foo142() {
|
2015-02-19 19:00:11 +00:00
|
|
|
t := new(Tm) // ERROR "new\(Tm\) escapes to heap$"
|
|
|
|
gf = t.M // ERROR "t.M escapes to heap$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
// issue 3888.
|
|
|
|
func foo143() {
|
|
|
|
for i := 0; i < 1000; i++ {
|
2015-02-19 19:00:11 +00:00
|
|
|
func() { // ERROR "foo143 func literal does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
for i := 0; i < 1; i++ {
|
|
|
|
var t Tm
|
2015-05-27 11:31:56 +00:00
|
|
|
t.M() // ERROR "foo143.func1 t does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
}()
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
// issue 5773
|
|
|
|
// Check that annotations take effect regardless of whether they
|
|
|
|
// are before or after the use in the source code.
|
|
|
|
|
|
|
|
//go:noescape
|
|
|
|
|
|
|
|
func foo144a(*int)
|
|
|
|
|
|
|
|
func foo144() {
|
|
|
|
var x int
|
2015-02-19 19:00:11 +00:00
|
|
|
foo144a(&x) // ERROR "foo144 &x does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
var y int
|
2015-02-19 19:00:11 +00:00
|
|
|
foo144b(&y) // ERROR "foo144 &y does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
//go:noescape
|
|
|
|
|
|
|
|
func foo144b(*int)
|
|
|
|
|
|
|
|
// issue 7313: for loop init should not be treated as "in loop"
|
|
|
|
|
|
|
|
type List struct {
|
|
|
|
Next *List
|
|
|
|
}
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func foo145(l List) { // ERROR "foo145 l does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
var p *List
|
2015-02-19 19:00:11 +00:00
|
|
|
for p = &l; p.Next != nil; p = p.Next { // ERROR "foo145 &l does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func foo146(l List) { // ERROR "foo146 l does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
var p *List
|
2015-02-19 19:00:11 +00:00
|
|
|
p = &l // ERROR "foo146 &l does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
for ; p.Next != nil; p = p.Next {
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func foo147(l List) { // ERROR "foo147 l does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
var p *List
|
2015-02-19 19:00:11 +00:00
|
|
|
p = &l // ERROR "foo147 &l does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
for p.Next != nil {
|
|
|
|
p = p.Next
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func foo148(l List) { // ERROR "foo148 l does not escape$"
|
|
|
|
for p := &l; p.Next != nil; p = p.Next { // ERROR "foo148 &l does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
// related: address of variable should have depth of variable, not of loop
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func foo149(l List) { // ERROR "foo149 l does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
var p *List
|
|
|
|
for {
|
2015-02-19 19:00:11 +00:00
|
|
|
for p = &l; p.Next != nil; p = p.Next { // ERROR "foo149 &l does not escape$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
// issue 7934: missed ... if element type had no pointers
|
|
|
|
|
|
|
|
var save150 []byte
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func foo150(x ...byte) { // ERROR "leaking param: x$"
|
2014-09-24 19:20:03 +00:00
|
|
|
save150 = x
|
|
|
|
}
|
|
|
|
|
|
|
|
func bar150() {
|
2015-02-19 19:00:11 +00:00
|
|
|
foo150(1, 2, 3) // ERROR "... argument escapes to heap$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
// issue 7931: bad handling of slice of array
|
|
|
|
|
|
|
|
var save151 *int
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func foo151(x *int) { // ERROR "leaking param: x$"
|
2014-09-24 19:20:03 +00:00
|
|
|
save151 = x
|
|
|
|
}
|
|
|
|
|
|
|
|
func bar151() {
|
2015-02-19 19:00:11 +00:00
|
|
|
var a [64]int // ERROR "moved to heap: a$"
|
2014-09-24 19:20:03 +00:00
|
|
|
a[4] = 101
|
2015-02-19 19:00:11 +00:00
|
|
|
foo151(&(&a)[4:8][0]) // ERROR "&\(&a\)\[4:8\]\[0\] escapes to heap$" "&a escapes to heap$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
func bar151b() {
|
2015-02-19 19:00:11 +00:00
|
|
|
var a [10]int // ERROR "moved to heap: a$"
|
|
|
|
b := a[:] // ERROR "a escapes to heap$"
|
|
|
|
foo151(&b[4:8][0]) // ERROR "&b\[4:8\]\[0\] escapes to heap$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
func bar151c() {
|
2015-02-19 19:00:11 +00:00
|
|
|
var a [64]int // ERROR "moved to heap: a$"
|
2014-09-24 19:20:03 +00:00
|
|
|
a[4] = 101
|
2015-02-19 19:00:11 +00:00
|
|
|
foo151(&(&a)[4:8:8][0]) // ERROR "&\(&a\)\[4:8:8\]\[0\] escapes to heap$" "&a escapes to heap$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
func bar151d() {
|
2015-02-19 19:00:11 +00:00
|
|
|
var a [10]int // ERROR "moved to heap: a$"
|
|
|
|
b := a[:] // ERROR "a escapes to heap$"
|
|
|
|
foo151(&b[4:8:8][0]) // ERROR "&b\[4:8:8\]\[0\] escapes to heap$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
// issue 8120
|
|
|
|
|
|
|
|
type U struct {
|
|
|
|
s *string
|
|
|
|
}
|
|
|
|
|
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.${i}.prof ;
done
showed a 15% reduction in allocations performed by the compiler.
Update #3753
Update #4720
Fixes #10466
Change-Id: I0fd97d5f5ac527b45f49e2218d158a6e89951432
Reviewed-on: https://go-review.googlesource.com/8202
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2015-03-26 20:36:15 +00:00
|
|
|
func (u *U) String() *string { // ERROR "leaking param: u to result ~r0 level=1$"
|
2014-09-24 19:20:03 +00:00
|
|
|
return u.s
|
|
|
|
}
|
|
|
|
|
|
|
|
type V struct {
|
|
|
|
s *string
|
|
|
|
}
|
|
|
|
|
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>
2015-03-26 20:36:15 +00:00
|
|
|
// BAD -- level of leak ought to be 0
|
|
|
|
func NewV(u U) *V { // ERROR "leaking param: u to result ~r1 level=-1"
|
|
|
|
return &V{u.String()} // ERROR "&V literal escapes to heap$" "NewV u does not escape"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
func foo152() {
|
2015-02-19 19:00:11 +00:00
|
|
|
a := "a" // ERROR "moved to heap: a$"
|
|
|
|
u := U{&a} // ERROR "&a escapes to heap$"
|
2014-09-24 19:20:03 +00:00
|
|
|
v := NewV(u)
|
|
|
|
println(v)
|
|
|
|
}
|
|
|
|
|
|
|
|
// issue 8176 - &x in type switch body not marked as escaping
|
|
|
|
|
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.${i}.prof ;
done
showed a 15% reduction in allocations performed by the compiler.
Update #3753
Update #4720
Fixes #10466
Change-Id: I0fd97d5f5ac527b45f49e2218d158a6e89951432
Reviewed-on: https://go-review.googlesource.com/8202
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2015-03-26 20:36:15 +00:00
|
|
|
func foo153(v interface{}) *int { // ERROR "leaking param: v to result ~r1 level=-1$"
|
2014-09-24 19:20:03 +00:00
|
|
|
switch x := v.(type) {
|
2015-02-19 19:00:11 +00:00
|
|
|
case int: // ERROR "moved to heap: x$"
|
|
|
|
return &x // ERROR "&x escapes to heap$"
|
2014-09-24 19:20:03 +00:00
|
|
|
}
|
|
|
|
panic(0)
|
|
|
|
}
|
|
|
|
|
|
|
|
// issue 8185 - &result escaping into result
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func f() (x int, y *int) { // ERROR "moved to heap: x$"
|
|
|
|
y = &x // ERROR "&x escapes to heap$"
|
2014-09-24 19:20:03 +00:00
|
|
|
return
|
|
|
|
}
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func g() (x interface{}) { // ERROR "moved to heap: x$"
|
|
|
|
x = &x // ERROR "&x escapes to heap$"
|
2014-09-24 19:20:03 +00:00
|
|
|
return
|
|
|
|
}
|
2015-01-19 20:46:22 +00:00
|
|
|
|
|
|
|
var sink interface{}
|
|
|
|
|
|
|
|
type Lit struct {
|
|
|
|
p *int
|
|
|
|
}
|
|
|
|
|
|
|
|
func ptrlitNoescape() {
|
|
|
|
// Both literal and element do not escape.
|
|
|
|
i := 0
|
2015-02-19 19:00:11 +00:00
|
|
|
x := &Lit{&i} // ERROR "ptrlitNoescape &Lit literal does not escape$" "ptrlitNoescape &i does not escape$"
|
2015-01-19 20:46:22 +00:00
|
|
|
_ = x
|
|
|
|
}
|
|
|
|
|
|
|
|
func ptrlitNoEscape2() {
|
|
|
|
// Literal does not escape, but element does.
|
2015-02-19 19:00:11 +00:00
|
|
|
i := 0 // ERROR "moved to heap: i$"
|
|
|
|
x := &Lit{&i} // ERROR "&i escapes to heap$" "ptrlitNoEscape2 &Lit literal does not escape$"
|
|
|
|
sink = *x // ERROR "\*x escapes to heap$"
|
2015-01-19 20:46:22 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
func ptrlitEscape() {
|
|
|
|
// Both literal and element escape.
|
2015-02-19 19:00:11 +00:00
|
|
|
i := 0 // ERROR "moved to heap: i$"
|
|
|
|
x := &Lit{&i} // ERROR "&Lit literal escapes to heap$" "&i escapes to heap$"
|
|
|
|
sink = x // ERROR "x escapes to heap$"
|
2015-01-19 20:46:22 +00:00
|
|
|
}
|
2015-01-16 20:30:35 +00:00
|
|
|
|
|
|
|
// self-assignments
|
|
|
|
|
|
|
|
type Buffer struct {
|
|
|
|
arr [64]byte
|
|
|
|
buf1 []byte
|
|
|
|
buf2 []byte
|
|
|
|
str1 string
|
|
|
|
str2 string
|
|
|
|
}
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func (b *Buffer) foo() { // ERROR "\(\*Buffer\).foo b does not escape$"
|
|
|
|
b.buf1 = b.buf1[1:2] // ERROR "\(\*Buffer\).foo ignoring self-assignment to b.buf1$"
|
|
|
|
b.buf1 = b.buf1[1:2:3] // ERROR "\(\*Buffer\).foo ignoring self-assignment to b.buf1$"
|
|
|
|
b.buf1 = b.buf2[1:2] // ERROR "\(\*Buffer\).foo ignoring self-assignment to b.buf1$"
|
|
|
|
b.buf1 = b.buf2[1:2:3] // ERROR "\(\*Buffer\).foo ignoring self-assignment to b.buf1$"
|
2015-01-16 20:30:35 +00:00
|
|
|
}
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func (b *Buffer) bar() { // ERROR "leaking param: b$"
|
|
|
|
b.buf1 = b.arr[1:2] // ERROR "b.arr escapes to heap$"
|
2015-01-16 20:30:35 +00:00
|
|
|
}
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func (b *Buffer) baz() { // ERROR "\(\*Buffer\).baz b does not escape$"
|
|
|
|
b.str1 = b.str1[1:2] // ERROR "\(\*Buffer\).baz ignoring self-assignment to b.str1$"
|
|
|
|
b.str1 = b.str2[1:2] // ERROR "\(\*Buffer\).baz ignoring self-assignment to b.str1$"
|
2015-01-16 20:30:35 +00:00
|
|
|
}
|
|
|
|
|
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.${i}.prof ;
done
showed a 15% reduction in allocations performed by the compiler.
Update #3753
Update #4720
Fixes #10466
Change-Id: I0fd97d5f5ac527b45f49e2218d158a6e89951432
Reviewed-on: https://go-review.googlesource.com/8202
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2015-03-26 20:36:15 +00:00
|
|
|
func (b *Buffer) bat() { // ERROR "leaking param content: b$"
|
2015-02-19 19:00:11 +00:00
|
|
|
o := new(Buffer) // ERROR "new\(Buffer\) escapes to heap$"
|
2015-01-16 20:30:35 +00:00
|
|
|
o.buf1 = b.buf1[1:2]
|
2015-02-19 19:00:11 +00:00
|
|
|
sink = o // ERROR "o escapes to heap$"
|
2015-01-16 20:30:35 +00:00
|
|
|
}
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func quux(sp *string, bp *[]byte) { // ERROR "quux bp does not escape$" "quux sp does not escape$"
|
|
|
|
*sp = (*sp)[1:2] // ERROR "quux ignoring self-assignment to \*sp$"
|
|
|
|
*bp = (*bp)[1:2] // ERROR "quux ignoring self-assignment to \*bp$"
|
2015-01-16 20:30:35 +00:00
|
|
|
}
|
2015-01-21 14:37:59 +00:00
|
|
|
|
|
|
|
type StructWithString struct {
|
|
|
|
p *int
|
|
|
|
s string
|
|
|
|
}
|
|
|
|
|
|
|
|
// This is escape analysis false negative.
|
|
|
|
// We assign the pointer to x.p but leak x.s. Escape analysis coarsens flows
|
|
|
|
// to just x, and thus &i looks escaping.
|
|
|
|
func fieldFlowTracking() {
|
|
|
|
var x StructWithString
|
2015-02-19 19:00:11 +00:00
|
|
|
i := 0 // ERROR "moved to heap: i$"
|
|
|
|
x.p = &i // ERROR "&i escapes to heap$"
|
|
|
|
sink = x.s // ERROR "x.s escapes to heap$"
|
2015-01-21 14:37:59 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
// String operations.
|
|
|
|
|
|
|
|
func slicebytetostring0() {
|
2015-02-19 19:00:11 +00:00
|
|
|
b := make([]byte, 20) // ERROR "slicebytetostring0 make\(\[\]byte, 20\) does not escape$"
|
|
|
|
s := string(b) // ERROR "slicebytetostring0 string\(b\) does not escape$"
|
2015-01-21 14:37:59 +00:00
|
|
|
_ = s
|
|
|
|
}
|
|
|
|
|
|
|
|
func slicebytetostring1() {
|
2015-02-19 19:00:11 +00:00
|
|
|
b := make([]byte, 20) // ERROR "slicebytetostring1 make\(\[\]byte, 20\) does not escape$"
|
|
|
|
s := string(b) // ERROR "slicebytetostring1 string\(b\) does not escape$"
|
2015-01-21 14:37:59 +00:00
|
|
|
s1 := s[0:1]
|
|
|
|
_ = s1
|
|
|
|
}
|
|
|
|
|
|
|
|
func slicebytetostring2() {
|
2015-02-19 19:00:11 +00:00
|
|
|
b := make([]byte, 20) // ERROR "slicebytetostring2 make\(\[\]byte, 20\) does not escape$"
|
|
|
|
s := string(b) // ERROR "string\(b\) escapes to heap$"
|
|
|
|
s1 := s[0:1] // ERROR "moved to heap: s1$"
|
|
|
|
sink = &s1 // ERROR "&s1 escapes to heap$"
|
2015-01-21 14:37:59 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
func slicebytetostring3() {
|
2015-02-19 19:00:11 +00:00
|
|
|
b := make([]byte, 20) // ERROR "slicebytetostring3 make\(\[\]byte, 20\) does not escape$"
|
|
|
|
s := string(b) // ERROR "string\(b\) escapes to heap$"
|
2015-01-21 14:37:59 +00:00
|
|
|
s1 := s[0:1]
|
2015-02-19 19:00:11 +00:00
|
|
|
sink = s1 // ERROR "s1 escapes to heap$"
|
2015-01-21 14:37:59 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
func addstr0() {
|
|
|
|
s0 := "a"
|
|
|
|
s1 := "b"
|
2015-02-19 19:00:11 +00:00
|
|
|
s := s0 + s1 // ERROR "addstr0 s0 \+ s1 does not escape$"
|
2015-01-21 14:37:59 +00:00
|
|
|
_ = s
|
|
|
|
}
|
|
|
|
|
|
|
|
func addstr1() {
|
|
|
|
s0 := "a"
|
|
|
|
s1 := "b"
|
|
|
|
s := "c"
|
2015-02-19 19:00:11 +00:00
|
|
|
s += s0 + s1 // ERROR "addstr1 s0 \+ s1 does not escape$"
|
2015-01-21 14:37:59 +00:00
|
|
|
_ = s
|
|
|
|
}
|
|
|
|
|
|
|
|
func addstr2() {
|
2015-02-19 19:00:11 +00:00
|
|
|
b := make([]byte, 20) // ERROR "addstr2 make\(\[\]byte, 20\) does not escape$"
|
2015-01-21 14:37:59 +00:00
|
|
|
s0 := "a"
|
2015-02-19 19:00:11 +00:00
|
|
|
s := string(b) + s0 // ERROR "addstr2 string\(b\) \+ s0 does not escape$" "addstr2 string\(b\) does not escape$"
|
2015-01-21 14:37:59 +00:00
|
|
|
_ = s
|
|
|
|
}
|
|
|
|
|
|
|
|
func addstr3() {
|
|
|
|
s0 := "a"
|
|
|
|
s1 := "b"
|
2015-02-19 19:00:11 +00:00
|
|
|
s := s0 + s1 // ERROR "s0 \+ s1 escapes to heap$"
|
2015-01-21 14:37:59 +00:00
|
|
|
s2 := s[0:1]
|
2015-02-19 19:00:11 +00:00
|
|
|
sink = s2 // ERROR "s2 escapes to heap$"
|
2015-01-21 14:37:59 +00:00
|
|
|
}
|
2015-01-28 05:42:20 +00:00
|
|
|
|
|
|
|
func intstring0() bool {
|
|
|
|
// string does not escape
|
|
|
|
x := '0'
|
2015-02-19 19:00:11 +00:00
|
|
|
s := string(x) // ERROR "intstring0 string\(x\) does not escape$"
|
2015-01-28 05:42:20 +00:00
|
|
|
return s == "0"
|
|
|
|
}
|
|
|
|
|
|
|
|
func intstring1() string {
|
|
|
|
// string does not escape, but the buffer does
|
|
|
|
x := '0'
|
2015-02-19 19:00:11 +00:00
|
|
|
s := string(x) // ERROR "string\(x\) escapes to heap$"
|
2015-01-28 05:42:20 +00:00
|
|
|
return s
|
|
|
|
}
|
|
|
|
|
|
|
|
func intstring2() {
|
|
|
|
// string escapes to heap
|
|
|
|
x := '0'
|
2015-02-19 19:00:11 +00:00
|
|
|
s := string(x) // ERROR "moved to heap: s$" "string\(x\) escapes to heap$"
|
|
|
|
sink = &s // ERROR "&s escapes to heap$"
|
2015-01-28 05:42:20 +00:00
|
|
|
}
|
2015-01-30 06:14:13 +00:00
|
|
|
|
|
|
|
func stringtoslicebyte0() {
|
|
|
|
s := "foo"
|
2015-02-19 19:00:11 +00:00
|
|
|
x := []byte(s) // ERROR "stringtoslicebyte0 \(\[\]byte\)\(s\) does not escape$"
|
2015-01-30 06:14:13 +00:00
|
|
|
_ = x
|
|
|
|
}
|
|
|
|
|
|
|
|
func stringtoslicebyte1() []byte {
|
|
|
|
s := "foo"
|
2015-02-19 19:00:11 +00:00
|
|
|
return []byte(s) // ERROR "\(\[\]byte\)\(s\) escapes to heap$"
|
2015-01-30 06:14:13 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
func stringtoslicebyte2() {
|
|
|
|
s := "foo"
|
2015-02-19 19:00:11 +00:00
|
|
|
sink = []byte(s) // ERROR "\(\[\]byte\)\(s\) escapes to heap$"
|
2015-01-30 06:14:13 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
func stringtoslicerune0() {
|
|
|
|
s := "foo"
|
2015-02-19 19:00:11 +00:00
|
|
|
x := []rune(s) // ERROR "stringtoslicerune0 \(\[\]rune\)\(s\) does not escape$"
|
2015-01-30 06:14:13 +00:00
|
|
|
_ = x
|
|
|
|
}
|
|
|
|
|
|
|
|
func stringtoslicerune1() []rune {
|
|
|
|
s := "foo"
|
2015-02-19 19:00:11 +00:00
|
|
|
return []rune(s) // ERROR "\(\[\]rune\)\(s\) escapes to heap$"
|
2015-01-30 06:14:13 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
func stringtoslicerune2() {
|
|
|
|
s := "foo"
|
2015-02-19 19:00:11 +00:00
|
|
|
sink = []rune(s) // ERROR "\(\[\]rune\)\(s\) escapes to heap$"
|
2015-01-30 06:14:13 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
func slicerunetostring0() {
|
2015-02-19 19:00:11 +00:00
|
|
|
r := []rune{1, 2, 3} // ERROR "slicerunetostring0 \[\]rune literal does not escape$"
|
|
|
|
s := string(r) // ERROR "slicerunetostring0 string\(r\) does not escape$"
|
2015-01-30 06:14:13 +00:00
|
|
|
_ = s
|
|
|
|
}
|
|
|
|
|
|
|
|
func slicerunetostring1() string {
|
2015-02-19 19:00:11 +00:00
|
|
|
r := []rune{1, 2, 3} // ERROR "slicerunetostring1 \[\]rune literal does not escape$"
|
|
|
|
return string(r) // ERROR "string\(r\) escapes to heap$"
|
2015-01-30 06:14:13 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
func slicerunetostring2() {
|
2015-02-19 19:00:11 +00:00
|
|
|
r := []rune{1, 2, 3} // ERROR "slicerunetostring2 \[\]rune literal does not escape$"
|
|
|
|
sink = string(r) // ERROR "string\(r\) escapes to heap$"
|
2015-01-30 06:14:13 +00:00
|
|
|
}
|
2015-01-29 16:40:02 +00:00
|
|
|
|
|
|
|
func makemap0() {
|
2015-02-19 19:00:11 +00:00
|
|
|
m := make(map[int]int) // ERROR "makemap0 make\(map\[int\]int\) does not escape$"
|
2015-01-29 16:40:02 +00:00
|
|
|
m[0] = 0
|
|
|
|
m[1]++
|
|
|
|
delete(m, 1)
|
2015-02-19 19:00:11 +00:00
|
|
|
sink = m[0] // ERROR "m\[0\] escapes to heap$"
|
2015-01-29 16:40:02 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
func makemap1() map[int]int {
|
2015-02-19 19:00:11 +00:00
|
|
|
return make(map[int]int) // ERROR "make\(map\[int\]int\) escapes to heap$"
|
2015-01-29 16:40:02 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
func makemap2() {
|
2015-02-19 19:00:11 +00:00
|
|
|
m := make(map[int]int) // ERROR "make\(map\[int\]int\) escapes to heap$"
|
|
|
|
sink = m // ERROR "m escapes to heap$"
|
2015-02-19 13:27:32 +00:00
|
|
|
}
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func nonescapingEface(m map[interface{}]bool) bool { // ERROR "nonescapingEface m does not escape$"
|
|
|
|
return m["foo"] // ERROR "nonescapingEface .foo. does not escape$"
|
2015-02-19 13:27:32 +00:00
|
|
|
}
|
|
|
|
|
2015-02-19 19:00:11 +00:00
|
|
|
func nonescapingIface(m map[M]bool) bool { // ERROR "nonescapingIface m does not escape$"
|
|
|
|
return m[MV(0)] // ERROR "nonescapingIface MV\(0\) does not escape$"
|
2015-01-29 16:40:02 +00:00
|
|
|
}
|
2015-04-06 15:17:20 +00:00
|
|
|
|
|
|
|
func issue10353() {
|
2015-02-19 19:00:11 +00:00
|
|
|
x := new(int) // ERROR "new\(int\) escapes to heap$"
|
2015-04-06 15:17:20 +00:00
|
|
|
issue10353a(x)()
|
|
|
|
}
|
|
|
|
|
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.${i}.prof ;
done
showed a 15% reduction in allocations performed by the compiler.
Update #3753
Update #4720
Fixes #10466
Change-Id: I0fd97d5f5ac527b45f49e2218d158a6e89951432
Reviewed-on: https://go-review.googlesource.com/8202
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
2015-03-26 20:36:15 +00:00
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func issue10353a(x *int) func() { // ERROR "leaking param: x to result ~r1 level=-1$"
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2015-02-19 19:00:11 +00:00
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return func() { // ERROR "func literal escapes to heap$"
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2015-04-06 15:17:20 +00:00
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println(*x)
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}
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}
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func issue10353b() {
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var f func()
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for {
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2015-02-19 19:00:11 +00:00
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x := new(int) // ERROR "new\(int\) escapes to heap$"
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f = func() { // ERROR "func literal escapes to heap$"
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2015-04-06 15:17:20 +00:00
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println(*x)
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}
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}
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_ = f
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}
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2015-06-24 21:31:57 +00:00
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func issue11387(x int) func() int {
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f := func() int { return x } // ERROR "func literal escapes to heap"
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slice1 := []func() int{f} // ERROR "\[\].* does not escape"
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slice2 := make([]func() int, 1) // ERROR "make\(.*\) does not escape"
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copy(slice2, slice1)
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return slice2[0]
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}
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