From 1c53a1b1975adf69c594fbbd5b1ca13d783f9817 Mon Sep 17 00:00:00 2001 From: Cherry Zhang Date: Thu, 1 Sep 2016 07:22:23 -0400 Subject: [PATCH] cmd/compile: fix scheduling of memory-producing tuple ops Intrinsified atomic op produces . Make sure this memory is considered in the store chain calculation. Fixes #16948. Change-Id: I029f164b123a7e830214297f8373f06ea0bf1e26 Reviewed-on: https://go-review.googlesource.com/28350 Run-TryBot: Cherry Zhang TryBot-Result: Gobot Gobot Reviewed-by: Keith Randall --- src/cmd/compile/internal/ssa/schedule.go | 6 ++++- test/fixedbugs/issue16948.go | 34 ++++++++++++++++++++++++ 2 files changed, 39 insertions(+), 1 deletion(-) create mode 100644 test/fixedbugs/issue16948.go diff --git a/src/cmd/compile/internal/ssa/schedule.go b/src/cmd/compile/internal/ssa/schedule.go index bf3fb27f90..ffc816b00f 100644 --- a/src/cmd/compile/internal/ssa/schedule.go +++ b/src/cmd/compile/internal/ssa/schedule.go @@ -128,9 +128,13 @@ func schedule(f *Func) { // the calculated store chain is good only for this block. for _, v := range b.Values { if v.Op != OpPhi && v.Type.IsMemory() { + mem := v + if v.Op == OpSelect1 { + v = v.Args[0] + } for _, w := range v.Args { if w.Type.IsMemory() { - nextMem[w.ID] = v + nextMem[w.ID] = mem } } } diff --git a/test/fixedbugs/issue16948.go b/test/fixedbugs/issue16948.go new file mode 100644 index 0000000000..c986024896 --- /dev/null +++ b/test/fixedbugs/issue16948.go @@ -0,0 +1,34 @@ +// run + +// Copyright 2016 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. + +// issue 16948: make sure intrinsified atomic ops won't +// confuse the scheduler. + +package main + +import "sync/atomic" + +func main() { + f() +} + +var x int32 + +type T [10]int +var sink *T + +func f() (t T) { + atomic.AddInt32(&x, 1) + g(42, 42, 42, 42, 42, &t) // use int values that is invalid pointer to smash the stack slot of return value of runtime.newobject + return +} + +//go:noinline +func g(a, b, c, d, e int, p *T) { + var t [10000]int // a large stack frame to trigger stack growing + _ = t + sink = p // force p (in caller) heap allocated +} -- 2.48.1