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author | Michael Munday <mike.munday@ibm.com> | 2018-03-19 13:11:16 -0400 |
---|---|---|
committer | Andrew Bonventre <andybons@golang.org> | 2018-03-29 06:08:34 +0000 |
commit | 4e19a5498d82ad49b4a5b3de2032bcb341211458 (patch) | |
tree | 188d9ceba7accd3ebc0028c84394d786508a9631 | |
parent | df9d6204b92c6cba7b0b2104b570f20956dd6568 (diff) | |
download | go-4e19a5498d82ad49b4a5b3de2032bcb341211458.tar.gz go-4e19a5498d82ad49b4a5b3de2032bcb341211458.zip |
[release-branch.go1.10] cmd/compile: mark LAA and LAAG as clobbering flags on s390x
The atomic add instructions modify the condition code and so need to
be marked as clobbering flags.
Fixes #24449.
Change-Id: Ic69c8d775fbdbfb2a56c5e0cfca7a49c0d7f6897
Reviewed-on: https://go-review.googlesource.com/101455
Run-TryBot: Michael Munday <mike.munday@ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-on: https://go-review.googlesource.com/102788
Run-TryBot: Andrew Bonventre <andybons@golang.org>
Reviewed-by: Michael Munday <mike.munday@ibm.com>
-rw-r--r-- | src/cmd/compile/internal/ssa/gen/S390XOps.go | 4 | ||||
-rw-r--r-- | src/cmd/compile/internal/ssa/opGen.go | 2 | ||||
-rw-r--r-- | test/fixedbugs/issue24449.go | 62 |
3 files changed, 66 insertions, 2 deletions
diff --git a/src/cmd/compile/internal/ssa/gen/S390XOps.go b/src/cmd/compile/internal/ssa/gen/S390XOps.go index d12dfe78bb..e458e08a1a 100644 --- a/src/cmd/compile/internal/ssa/gen/S390XOps.go +++ b/src/cmd/compile/internal/ssa/gen/S390XOps.go @@ -485,8 +485,8 @@ func init() { // Atomic adds. // *(arg0+auxint+aux) += arg1. arg2=mem. // Returns a tuple of <old contents of *(arg0+auxint+aux), memory>. - {name: "LAA", argLength: 3, reg: gpstorelaa, asm: "LAA", typ: "(UInt32,Mem)", aux: "SymOff", faultOnNilArg0: true, hasSideEffects: true, symEffect: "RdWr"}, - {name: "LAAG", argLength: 3, reg: gpstorelaa, asm: "LAAG", typ: "(UInt64,Mem)", aux: "SymOff", faultOnNilArg0: true, hasSideEffects: true, symEffect: "RdWr"}, + {name: "LAA", argLength: 3, reg: gpstorelaa, asm: "LAA", typ: "(UInt32,Mem)", aux: "SymOff", clobberFlags: true, faultOnNilArg0: true, hasSideEffects: true, symEffect: "RdWr"}, + {name: "LAAG", argLength: 3, reg: gpstorelaa, asm: "LAAG", typ: "(UInt64,Mem)", aux: "SymOff", clobberFlags: true, faultOnNilArg0: true, hasSideEffects: true, symEffect: "RdWr"}, {name: "AddTupleFirst32", argLength: 2}, // arg1=tuple <x,y>. Returns <x+arg0,y>. {name: "AddTupleFirst64", argLength: 2}, // arg1=tuple <x,y>. Returns <x+arg0,y>. diff --git a/src/cmd/compile/internal/ssa/opGen.go b/src/cmd/compile/internal/ssa/opGen.go index 0beabb0b84..d50561cdf0 100644 --- a/src/cmd/compile/internal/ssa/opGen.go +++ b/src/cmd/compile/internal/ssa/opGen.go @@ -22080,6 +22080,7 @@ var opcodeTable = [...]opInfo{ name: "LAA", auxType: auxSymOff, argLen: 3, + clobberFlags: true, faultOnNilArg0: true, hasSideEffects: true, symEffect: SymRdWr, @@ -22098,6 +22099,7 @@ var opcodeTable = [...]opInfo{ name: "LAAG", auxType: auxSymOff, argLen: 3, + clobberFlags: true, faultOnNilArg0: true, hasSideEffects: true, symEffect: SymRdWr, diff --git a/test/fixedbugs/issue24449.go b/test/fixedbugs/issue24449.go new file mode 100644 index 0000000000..b236645103 --- /dev/null +++ b/test/fixedbugs/issue24449.go @@ -0,0 +1,62 @@ +// run + +// Copyright 2018 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package main + +import ( + "sync/atomic" +) + +var cnt32 int32 + +//go:noinline +func test32(a, b []int) bool { + // Try to generate flag value, issue atomic + // adds and then re-use the flag value to see if + // the atomic add has clobbered them. + atomic.AddInt32(&cnt32, 1) + if len(a) == len(b) { + atomic.AddInt32(&cnt32, 2) + } + atomic.AddInt32(&cnt32, 4) + if len(a) >= len(b) { + atomic.AddInt32(&cnt32, 8) + } + if len(a) <= len(b) { + atomic.AddInt32(&cnt32, 16) + } + return atomic.LoadInt32(&cnt32) == 31 +} + +var cnt64 int64 + +//go:noinline +func test64(a, b []int) bool { + // Try to generate flag value, issue atomic + // adds and then re-use the flag value to see if + // the atomic add has clobbered them. + atomic.AddInt64(&cnt64, 1) + if len(a) == len(b) { + atomic.AddInt64(&cnt64, 2) + } + atomic.AddInt64(&cnt64, 4) + if len(a) >= len(b) { + atomic.AddInt64(&cnt64, 8) + } + if len(a) <= len(b) { + atomic.AddInt64(&cnt64, 16) + } + return atomic.LoadInt64(&cnt64) == 31 +} + +func main() { + if !test32([]int{}, []int{}) { + panic("test32") + } + if !test64([]int{}, []int{}) { + panic("test64") + } +} |