From 155328790b9324080e3f086ff9515f665abf67d1 Mon Sep 17 00:00:00 2001
From: Benjamin Kramer <benny.kra@googlemail.com>
Date: Sun, 29 Mar 2015 20:33:07 +0000
Subject: [PATCH] [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
---
lib/IR/InlineAsm.cpp | 3 ++-
test/CodeGen/X86/inline-asm-duplicated-constraint.ll | 12 ++++++++++++
2 files changed, 14 insertions(+), 1 deletion(-)
create mode 100644 test/CodeGen/X86/inline-asm-duplicated-constraint.ll
diff --git a/lib/IR/InlineAsm.cpp b/lib/IR/InlineAsm.cpp
index b456d9f5869..47dce20a517 100644
--- a/lib/IR/InlineAsm.cpp
+++ b/lib/IR/InlineAsm.cpp
@@ -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();
diff --git a/test/CodeGen/X86/inline-asm-duplicated-constraint.ll b/test/CodeGen/X86/inline-asm-duplicated-constraint.ll
new file mode 100644
index 00000000000..2ef54749739
--- /dev/null
+++ b/test/CodeGen/X86/inline-asm-duplicated-constraint.ll
@@ -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
+}
--
2.40.0