Author: majnemer
Date: Sat Jul 25 00:57:24 2015
New Revision: 243206
URL: http://llvm.org/viewvc/llvm-project?rev=243206&view=rev
Log:
[CodeGen] Don't UBSan-ize the argument to __builtin_frame_address
__builtin_frame_address requires its argument to be a constant
expression which already implies that it cannot have undefined behavior.
However, we used EmitScalarExpr to emit the argument causing UBSan to
try to check for overflow.
Instead, use the constant expression emission system.
This fixes PR24256.
Modified:
cfe/trunk/lib/CodeGen/CGBuiltin.cpp
cfe/trunk/test/CodeGen/integer-overflow.c
Modified: cfe/trunk/lib/CodeGen/CGBuiltin.cpp
URL:
http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CGBuiltin.cpp?rev=243206&r1=243205&r2=243206&view=diff
==============================================================================
--- cfe/trunk/lib/CodeGen/CGBuiltin.cpp (original)
+++ cfe/trunk/lib/CodeGen/CGBuiltin.cpp Sat Jul 25 00:57:24 2015
@@ -866,14 +866,14 @@ RValue CodeGenFunction::EmitBuiltinExpr(
llvm::ConstantInt::get(Int32Ty,
Offset)));
}
case Builtin::BI__builtin_return_address: {
- Value *Depth = EmitScalarExpr(E->getArg(0));
- Depth = Builder.CreateIntCast(Depth, Int32Ty, false);
+ Value *Depth =
+ CGM.EmitConstantExpr(E->getArg(0), getContext().UnsignedIntTy, this);
Value *F = CGM.getIntrinsic(Intrinsic::returnaddress);
return RValue::get(Builder.CreateCall(F, Depth));
}
case Builtin::BI__builtin_frame_address: {
- Value *Depth = EmitScalarExpr(E->getArg(0));
- Depth = Builder.CreateIntCast(Depth, Int32Ty, false);
+ Value *Depth =
+ CGM.EmitConstantExpr(E->getArg(0), getContext().UnsignedIntTy, this);
Value *F = CGM.getIntrinsic(Intrinsic::frameaddress);
return RValue::get(Builder.CreateCall(F, Depth));
}
Modified: cfe/trunk/test/CodeGen/integer-overflow.c
URL:
http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGen/integer-overflow.c?rev=243206&r1=243205&r2=243206&view=diff
==============================================================================
--- cfe/trunk/test/CodeGen/integer-overflow.c (original)
+++ cfe/trunk/test/CodeGen/integer-overflow.c Sat Jul 25 00:57:24 2015
@@ -72,4 +72,11 @@ void test1() {
// TRAPV: add i8 {{.*}}, 1
// CATCH_UB: add i8 {{.*}}, 1
++PR9350;
+
+ // PR24256: don't instrument __builtin_frame_address.
+ __builtin_frame_address(0 + 0);
+ // DEFAULT: call i8* @llvm.frameaddress(i32 0)
+ // WRAPV: call i8* @llvm.frameaddress(i32 0)
+ // TRAPV: call i8* @llvm.frameaddress(i32 0)
+ // CATCH_UB: call i8* @llvm.frameaddress(i32 0)
}
_______________________________________________
cfe-commits mailing list
cfe-commits@cs.uiuc.edu
http://lists.cs.uiuc.edu/mailman/listinfo/cfe-commits
