diff options
Diffstat (limited to 'lib/IR/ConstantFold.cpp')
-rw-r--r-- | lib/IR/ConstantFold.cpp | 13 |
1 files changed, 7 insertions, 6 deletions
diff --git a/lib/IR/ConstantFold.cpp b/lib/IR/ConstantFold.cpp index bf93d4f..8c5a983 100644 --- a/lib/IR/ConstantFold.cpp +++ b/lib/IR/ConstantFold.cpp @@ -75,7 +75,7 @@ static unsigned foldConstantCastPair( unsigned opc, ///< opcode of the second cast constant expression ConstantExpr *Op, ///< the first cast constant expression - Type *DstTy ///< desintation type of the first cast + Type *DstTy ///< destination type of the first cast ) { assert(Op && Op->isCast() && "Can't fold cast of cast without a cast!"); assert(DstTy && DstTy->isFirstClassType() && "Invalid cast destination type"); @@ -87,13 +87,14 @@ foldConstantCastPair( Instruction::CastOps firstOp = Instruction::CastOps(Op->getOpcode()); Instruction::CastOps secondOp = Instruction::CastOps(opc); - // Assume that pointers are never more than 64 bits wide. + // Assume that pointers are never more than 64 bits wide, and only use this + // for the middle type. Otherwise we could end up folding away illegal + // bitcasts between address spaces with different sizes. IntegerType *FakeIntPtrTy = Type::getInt64Ty(DstTy->getContext()); // Let CastInst::isEliminableCastPair do the heavy lifting. return CastInst::isEliminableCastPair(firstOp, secondOp, SrcTy, MidTy, DstTy, - FakeIntPtrTy, FakeIntPtrTy, - FakeIntPtrTy); + 0, FakeIntPtrTy, 0); } static Constant *FoldBitCast(Constant *V, Type *DestTy) { @@ -1857,9 +1858,9 @@ Constant *llvm::ConstantFoldCompareInstruction(unsigned short pred, if (CE1Inverse == CE1Op0) { // Check whether we can safely truncate the right hand side. Constant *C2Inverse = ConstantExpr::getTrunc(C2, CE1Op0->getType()); - if (ConstantExpr::getZExt(C2Inverse, C2->getType()) == C2) { + if (ConstantExpr::getCast(CE1->getOpcode(), C2Inverse, + C2->getType()) == C2) return ConstantExpr::getICmp(pred, CE1Inverse, C2Inverse); - } } } } |