Emit an error message if the value passed to __builtin_returnaddress isn't a constant

__builtin_returnaddress requires that the value passed into is be a constant.
However, at -O0 even a constant expression may not be converted to a constant.
Emit an error message intead of crashing.

llvm-svn: 198531

1 files changed, 7 insertions, 0 deletions

diff --git a/llvm/lib/Target/PowerPC/PPCISelLowering.cpp b/llvm/lib/Target/PowerPC/PPCISelLowering.cpp
index a00e37ab988..630385cc7c0 100644
--- a/llvm/lib/Target/PowerPC/PPCISelLowering.cpp
+++ b/llvm/lib/Target/PowerPC/PPCISelLowering.cpp
@@ -30,6 +30,7 @@
 #include "llvm/IR/DerivedTypes.h"
 #include "llvm/IR/Function.h"
 #include "llvm/IR/Intrinsics.h"
+#include "llvm/IR/LLVMContext.h"
 #include "llvm/Support/CommandLine.h"
 #include "llvm/Support/ErrorHandling.h"
 #include "llvm/Support/MathExtras.h"
@@ -7795,6 +7796,12 @@ SDValue PPCTargetLowering::LowerRETURNADDR(SDValue Op,
   MachineFrameInfo *MFI = MF.getFrameInfo();
   MFI->setReturnAddressIsTaken(true);
 
+  if (!isa<ConstantSDNode>(Op.getOperand(0))) {
+    DAG.getContext()->emitError("argument to '__builtin_return_address' must "
+                                "be a constant integer");
+    return SDValue();
+  }
+
   SDLoc dl(Op);
   unsigned Depth = cast<ConstantSDNode>(Op.getOperand(0))->getZExtValue();