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[oota-llvm.git] / lib / Transforms / InstCombine / InstCombineLoadStoreAlloca.cpp

diff --git a/lib/Transforms/InstCombine/InstCombineLoadStoreAlloca.cpp b/lib/Transforms/InstCombine/InstCombineLoadStoreAlloca.cpp
index f233ca6af1d22522fbb74a678f043cf7047b2a31..cf529625e263c45f1029e854aed769437fc65763 100644 (file)
--- a/lib/Transforms/InstCombine/InstCombineLoadStoreAlloca.cpp
+++ b/lib/Transforms/InstCombine/InstCombineLoadStoreAlloca.cpp
@@ -57,12 +57,14 @@ Instruction *InstCombiner::visitAllocaInst(AllocaInst &AI) {
       Value *Idx[2];
       Idx[0] = NullIdx;
       Idx[1] = NullIdx;
-      Value *V = GetElementPtrInst::CreateInBounds(New, Idx, Idx + 2,
-                                                   New->getName()+".sub", It);
+      Instruction *GEP =
+           GetElementPtrInst::CreateInBounds(New, Idx, Idx + 2,
+                                             New->getName()+".sub");
+      InsertNewInstBefore(GEP, *It);
 
       // Now make everything use the getelementptr instead of the original
       // allocation.
-      return ReplaceInstUsesWith(AI, V);
+      return ReplaceInstUsesWith(AI, GEP);
     } else if (isa<UndefValue>(AI.getArraySize())) {
       return ReplaceInstUsesWith(AI, Constant::getNullValue(AI.getType()));
     }
@@ -429,19 +431,9 @@ Instruction *InstCombiner::visitStoreInst(StoreInst &SI) {
     // the pointer we're loading and is producing the pointer we're storing,
     // then *this* store is dead (X = load P; store X -> P).
     if (LoadInst *LI = dyn_cast<LoadInst>(BBI)) {
-      if (equivalentAddressValues(LI->getOperand(0), Ptr) &&
-          !SI.isVolatile()) {
-        if (LI == Val)
-          return EraseInstFromFunction(SI);
-        if (Ptr->hasNUses(2)) {
-          if (GetElementPtrInst *GEP = dyn_cast<GetElementPtrInst>(Ptr)) {
-            if (isa<AllocaInst>(GEP->getOperand(0))) {
-              if (GEP->getOperand(0)->hasOneUse())
-                return EraseInstFromFunction(SI);
-            }
-          }
-        }
-      }
+      if (LI == Val && equivalentAddressValues(LI->getOperand(0), Ptr) &&
+          !SI.isVolatile())
+        return EraseInstFromFunction(SI);
       
       // Otherwise, this is a load from some other location.  Stores before it
       // may not be dead.
@@ -601,8 +593,7 @@ bool InstCombiner::SimplifyStoreAtEndOfBlock(StoreInst &SI) {
   // Insert a PHI node now if we need it.
   Value *MergedVal = OtherStore->getOperand(0);
   if (MergedVal != SI.getOperand(0)) {
-    PHINode *PN = PHINode::Create(MergedVal->getType(), "storemerge");
-    PN->reserveOperandSpace(2);
+    PHINode *PN = PHINode::Create(MergedVal->getType(), 2, "storemerge");
     PN->addIncoming(SI.getOperand(0), SI.getParent());
     PN->addIncoming(OtherStore->getOperand(0), OtherBB);
     MergedVal = InsertNewInstBefore(PN, DestBB->front());