Fix an instcombine abort on a scalar-to-vector bitcast. This fixes PR4487.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@74646 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Transforms/Scalar/InstructionCombining.cpp b/lib/Transforms/Scalar/InstructionCombining.cpp
index 5bd17e0..16e5ce0 100644
--- a/lib/Transforms/Scalar/InstructionCombining.cpp
+++ b/lib/Transforms/Scalar/InstructionCombining.cpp
@@ -1085,8 +1085,22 @@
break;
}
case Instruction::BitCast:
- if (!I->getOperand(0)->getType()->isInteger())
+ if (!I->getOperand(0)->getType()->isIntOrIntVector())
return false; // vector->int or fp->int?
+
+ if (const VectorType *DstVTy = dyn_cast<VectorType>(I->getType())) {
+ if (const VectorType *SrcVTy =
+ dyn_cast<VectorType>(I->getOperand(0)->getType())) {
+ if (DstVTy->getNumElements() != SrcVTy->getNumElements())
+ // Don't touch a bitcast between vectors of different element counts.
+ return false;
+ } else
+ // Don't touch a scalar-to-vector bitcast.
+ return false;
+ } else if (isa<VectorType>(I->getOperand(0)->getType()))
+ // Don't touch a vector-to-scalar bitcast.
+ return false;
+
if (SimplifyDemandedBits(I->getOperandUse(0), DemandedMask,
RHSKnownZero, RHSKnownOne, Depth+1))
return I;