[inline asm] Don't reject duplicated matching constraints

They're harmless and it's easy to generate them from clang, leading to
a crash in LLVM. Found by afl-fuzz.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@233500 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Benjamin Kramer 2015-03-29 20:33:07 +00:00
parent 041c54b85e
commit 155328790b
2 changed files with 14 additions and 1 deletions

View File

@ -167,7 +167,8 @@ bool InlineAsm::ConstraintInfo::Parse(StringRef Str,
// Note that operand #n has a matching input.
scInfo.MatchingInput = ConstraintsSoFar.size();
} else {
if (ConstraintsSoFar[N].hasMatchingInput())
if (ConstraintsSoFar[N].hasMatchingInput() &&
ConstraintsSoFar[N].MatchingInput != ConstraintsSoFar.size())
return true;
// Note that operand #n has a matching input.
ConstraintsSoFar[N].MatchingInput = ConstraintsSoFar.size();

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@ -0,0 +1,12 @@
; RUN: llc < %s -march=x86-64 -no-integrated-as -mtriple=x86_64-linux-gnu | FileCheck %s
; CHECK-LABEL: test1:
; CHECK: movl (%rdi), %eax
; CHECK: nop
; CHECK: movl %eax, (%rdi)
; CHECK: ret
define void @test1(i32* %l) {
%load = load i32, i32* %l
call void asm "nop", "=*rmrm,0m0m,~{dirflag},~{fpsr},~{flags}"(i32* %l, i32 %load)
ret void
}