+ // Don't hack volatile/atomic stores.
+ // FIXME: Some bits are legal for atomic stores; needs refactoring.
+ if (!SI.isSimple()) return 0;
+
+ // If the RHS is an alloca with a single use, zapify the store, making the
+ // alloca dead.
+ if (Ptr->hasOneUse()) {
+ if (isa<AllocaInst>(Ptr))
+ return EraseInstFromFunction(SI);
+ if (GetElementPtrInst *GEP = dyn_cast<GetElementPtrInst>(Ptr)) {
+ if (isa<AllocaInst>(GEP->getOperand(0))) {
+ if (GEP->getOperand(0)->hasOneUse())
+ return EraseInstFromFunction(SI);
+ }
+ }
+ }
+