From 4f083c7dcf6ace3e837b337e10cf2f4e3160677e Mon Sep 17 00:00:00 2001 From: hanpro Date: Fri, 5 Nov 2021 09:47:54 +0800 Subject: [PATCH] cmd/compile: avoid adding LECall to the entry block when has opendefers The openDeferRecord always insert vardef/varlive pairs into the entry block, it may destroy the mem chain when LECall's args are writing into the same block. So create a new block before that happens. Fixes #49282 Change-Id: Ibda6c4a45d960dd412a641f5e02276f663c80785 Reviewed-on: https://go-review.googlesource.com/c/go/+/361410 Run-TryBot: Alberto Donizetti TryBot-Result: Go Bot Trust: Alberto Donizetti Trust: Than McIntosh Reviewed-by: David Chase --- src/cmd/compile/internal/ssagen/ssa.go | 12 +++++++ test/fixedbugs/issue49282.go | 44 ++++++++++++++++++++++++++ 2 files changed, 56 insertions(+) create mode 100644 test/fixedbugs/issue49282.go diff --git a/src/cmd/compile/internal/ssagen/ssa.go b/src/cmd/compile/internal/ssagen/ssa.go index b84199790f..0853242e6f 100644 --- a/src/cmd/compile/internal/ssagen/ssa.go +++ b/src/cmd/compile/internal/ssagen/ssa.go @@ -5075,6 +5075,18 @@ func (s *state) call(n *ir.CallExpr, k callKind, returnResultAddr bool) *ssa.Val for _, p := range params.InParams() { // includes receiver for interface calls ACArgs = append(ACArgs, p.Type) } + + // Split the entry block if there are open defers, because later calls to + // openDeferSave may cause a mismatch between the mem for an OpDereference + // and the call site which uses it. See #49282. + if s.curBlock.ID == s.f.Entry.ID && s.hasOpenDefers { + b := s.endBlock() + b.Kind = ssa.BlockPlain + curb := s.f.NewBlock(ssa.BlockPlain) + b.AddEdgeTo(curb) + s.startBlock(curb) + } + for i, n := range args { callArgs = append(callArgs, s.putArg(n, t.Params().Field(i).Type)) } diff --git a/test/fixedbugs/issue49282.go b/test/fixedbugs/issue49282.go new file mode 100644 index 0000000000..7543075ca1 --- /dev/null +++ b/test/fixedbugs/issue49282.go @@ -0,0 +1,44 @@ +// compile + +// Copyright 2021 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 p + +//go:noinline +func g(d uintptr, a, m []int, s struct { + a, b, c, d, e int +}, u uint) { + _ = a + _ = m + _ = s + func() { + for i := 0; i < 5; i++ { + _ = a + _ = m + _, _ = s, s + } + }() +} + +var One float64 = 1.0 + +func f(d uintptr) { + var a, m []int + var s struct { + a, b, c, d, e int + } + + g(d, a, m, s, uint(One)) // Uint of not-a-constant inserts a conditional, necessary to bug + + defer func() uint { + return 0 + }() +} + +var d uintptr + +func h() { + f(d) +} -- 2.48.1