diff options
| -rw-r--r-- | lib/Transforms/Scalar/InstructionCombining.cpp | 12 | ||||
| -rw-r--r-- | lib/Transforms/Scalar/SCCP.cpp | 4 |
2 files changed, 12 insertions, 4 deletions
diff --git a/lib/Transforms/Scalar/InstructionCombining.cpp b/lib/Transforms/Scalar/InstructionCombining.cpp index de528d956a..6502bb38fe 100644 --- a/lib/Transforms/Scalar/InstructionCombining.cpp +++ b/lib/Transforms/Scalar/InstructionCombining.cpp @@ -9338,8 +9338,11 @@ Instruction *InstCombiner::visitLoadInst(LoadInst &LI) { return ReplaceInstUsesWith(LI, LIB); } - if (GetElementPtrInst *GEPI = dyn_cast<GetElementPtrInst>(Op)) - if (isa<ConstantPointerNull>(GEPI->getOperand(0))) { + if (GetElementPtrInst *GEPI = dyn_cast<GetElementPtrInst>(Op)) { + const Value *GEPI0 = GEPI->getOperand(0); + // TODO: Consider a target hook for valid address spaces for this xform. + if (isa<ConstantPointerNull>(GEPI0) && + cast<PointerType>(GEPI0->getType())->getAddressSpace() == 0) { // Insert a new store to null instruction before the load to indicate // that this code is not reachable. We do this instead of inserting // an unreachable instruction directly because we cannot modify the @@ -9348,10 +9351,13 @@ Instruction *InstCombiner::visitLoadInst(LoadInst &LI) { Constant::getNullValue(Op->getType()), &LI); return ReplaceInstUsesWith(LI, UndefValue::get(LI.getType())); } + } if (Constant *C = dyn_cast<Constant>(Op)) { // load null/undef -> undef - if ((C->isNullValue() || isa<UndefValue>(C))) { + // TODO: Consider a target hook for valid address spaces for this xform. + if (isa<UndefValue>(C) || (C->isNullValue() && + cast<PointerType>(Op->getType())->getAddressSpace() == 0)) { // Insert a new store to null instruction before the load to indicate that // this code is not reachable. We do this instead of inserting an // unreachable instruction directly because we cannot modify the CFG. diff --git a/lib/Transforms/Scalar/SCCP.cpp b/lib/Transforms/Scalar/SCCP.cpp index d236039332..3a607cbd5f 100644 --- a/lib/Transforms/Scalar/SCCP.cpp +++ b/lib/Transforms/Scalar/SCCP.cpp @@ -1015,7 +1015,9 @@ void SCCPSolver::visitLoadInst(LoadInst &I) { if (PtrVal.isUndefined()) return; // The pointer is not resolved yet! if (PtrVal.isConstant() && !I.isVolatile()) { Value *Ptr = PtrVal.getConstant(); - if (isa<ConstantPointerNull>(Ptr)) { + // TODO: Consider a target hook for valid address spaces for this xform. + if (isa<ConstantPointerNull>(Ptr) && + cast<PointerType>(Ptr->getType())->getAddressSpace() == 0) { // load null -> null markConstant(IV, &I, Constant::getNullValue(I.getType())); return; |