Add arg_begin() and arg_end() to CallInst and InvokeInst; NFCI

[oota-llvm.git] / lib / Transforms / Utils / DemoteRegToStack.cpp

diff --git a/lib/Transforms/Utils/DemoteRegToStack.cpp b/lib/Transforms/Utils/DemoteRegToStack.cpp
index 69134fc69dcaaa14945560aa2f8bfef359d9bfc7..75a1dde57c4cc992f42f22a946b9690854431b3f 100644 (file)
--- a/lib/Transforms/Utils/DemoteRegToStack.cpp
+++ b/lib/Transforms/Utils/DemoteRegToStack.cpp
@@ -25,23 +25,36 @@ AllocaInst *llvm::DemoteRegToStack(Instruction &I, bool VolatileLoads,
                                    Instruction *AllocaPoint) {
   if (I.use_empty()) {
     I.eraseFromParent();
-    return 0;
+    return nullptr;
   }
 
   // Create a stack slot to hold the value.
   AllocaInst *Slot;
   if (AllocaPoint) {
-    Slot = new AllocaInst(I.getType(), 0,
+    Slot = new AllocaInst(I.getType(), nullptr,
                           I.getName()+".reg2mem", AllocaPoint);
   } else {
     Function *F = I.getParent()->getParent();
-    Slot = new AllocaInst(I.getType(), 0, I.getName()+".reg2mem",
-                          F->getEntryBlock().begin());
+    Slot = new AllocaInst(I.getType(), nullptr, I.getName() + ".reg2mem",
+                          &F->getEntryBlock().front());
+  }
+
+  // We cannot demote invoke instructions to the stack if their normal edge
+  // is critical. Therefore, split the critical edge and create a basic block
+  // into which the store can be inserted.
+  if (InvokeInst *II = dyn_cast<InvokeInst>(&I)) {
+    if (!II->getNormalDest()->getSinglePredecessor()) {
+      unsigned SuccNum = GetSuccessorNumber(II->getParent(), II->getNormalDest());
+      assert(isCriticalEdge(II, SuccNum) && "Expected a critical edge!");
+      BasicBlock *BB = SplitCriticalEdge(II, SuccNum);
+      assert(BB && "Unable to split critical edge.");
+      (void)BB;
+    }
   }
 
   // Change all of the users of the instruction to read from the stack slot.
   while (!I.use_empty()) {
-    Instruction *U = cast<Instruction>(I.use_back());
+    Instruction *U = cast<Instruction>(I.user_back());
     if (PHINode *PN = dyn_cast<PHINode>(U)) {
       // If this is a PHI node, we can't insert a load of the value before the
       // use.  Instead insert the load in the predecessor block corresponding
@@ -56,7 +69,7 @@ AllocaInst *llvm::DemoteRegToStack(Instruction &I, bool VolatileLoads,
       for (unsigned i = 0, e = PN->getNumIncomingValues(); i != e; ++i)
         if (PN->getIncomingValue(i) == &I) {
           Value *&V = Loads[PN->getIncomingBlock(i)];
-          if (V == 0) {
+          if (!V) {
             // Insert the load into the predecessor block
             V = new LoadInst(Slot, I.getName()+".reload", VolatileLoads,
                              PN->getIncomingBlock(i)->getTerminator());
@@ -71,36 +84,20 @@ AllocaInst *llvm::DemoteRegToStack(Instruction &I, bool VolatileLoads,
     }
   }
 
-
   // Insert stores of the computed value into the stack slot. We have to be
   // careful if I is an invoke instruction, because we can't insert the store
   // AFTER the terminator instruction.
   BasicBlock::iterator InsertPt;
   if (!isa<TerminatorInst>(I)) {
-    InsertPt = &I;
-    ++InsertPt;
+    InsertPt = ++I.getIterator();
+    for (; isa<PHINode>(InsertPt) || InsertPt->isEHPad(); ++InsertPt)
+      /* empty */;   // Don't insert before PHI nodes or landingpad instrs.
   } else {
     InvokeInst &II = cast<InvokeInst>(I);
-    if (II.getNormalDest()->getSinglePredecessor())
-      InsertPt = II.getNormalDest()->getFirstInsertionPt();
-    else {
-      // We cannot demote invoke instructions to the stack if their normal edge
-      // is critical.  Therefore, split the critical edge and insert the store
-      // in the newly created basic block.
-      unsigned SuccNum = GetSuccessorNumber(I.getParent(), II.getNormalDest());
-      TerminatorInst *TI = &cast<TerminatorInst>(I);
-      assert (isCriticalEdge(TI, SuccNum) &&
-              "Expected a critical edge!");
-      BasicBlock *BB = SplitCriticalEdge(TI, SuccNum);
-      assert (BB && "Unable to split critical edge.");
-      InsertPt = BB->getFirstInsertionPt();
-    }
+    InsertPt = II.getNormalDest()->getFirstInsertionPt();
   }
 
-  for (; isa<PHINode>(InsertPt) || isa<LandingPadInst>(InsertPt); ++InsertPt)
-    /* empty */;   // Don't insert before PHI nodes or landingpad instrs.
-
-  new StoreInst(&I, Slot, InsertPt);
+  new StoreInst(&I, Slot, &*InsertPt);
   return Slot;
 }
 
@@ -110,18 +107,18 @@ AllocaInst *llvm::DemoteRegToStack(Instruction &I, bool VolatileLoads,
 AllocaInst *llvm::DemotePHIToStack(PHINode *P, Instruction *AllocaPoint) {
   if (P->use_empty()) {
     P->eraseFromParent();
-    return 0;
+    return nullptr;
   }
 
   // Create a stack slot to hold the value.
   AllocaInst *Slot;
   if (AllocaPoint) {
-    Slot = new AllocaInst(P->getType(), 0,
+    Slot = new AllocaInst(P->getType(), nullptr,
                           P->getName()+".reg2mem", AllocaPoint);
   } else {
     Function *F = P->getParent()->getParent();
-    Slot = new AllocaInst(P->getType(), 0, P->getName()+".reg2mem",
-                          F->getEntryBlock().begin());
+    Slot = new AllocaInst(P->getType(), nullptr, P->getName() + ".reg2mem",
+                          &F->getEntryBlock().front());
   }
 
   // Iterate over each operand inserting a store in each predecessor.
@@ -135,12 +132,12 @@ AllocaInst *llvm::DemotePHIToStack(PHINode *P, Instruction *AllocaPoint) {
   }
 
   // Insert a load in place of the PHI and replace all uses.
-  BasicBlock::iterator InsertPt = P;
+  BasicBlock::iterator InsertPt = P->getIterator();
 
-  for (; isa<PHINode>(InsertPt) || isa<LandingPadInst>(InsertPt); ++InsertPt)
+  for (; isa<PHINode>(InsertPt) || InsertPt->isEHPad(); ++InsertPt)
     /* empty */;   // Don't insert before PHI nodes or landingpad instrs.
 
-  Value *V = new LoadInst(Slot, P->getName()+".reload", InsertPt);
+  Value *V = new LoadInst(Slot, P->getName() + ".reload", &*InsertPt);
   P->replaceAllUsesWith(V);
 
   // Delete PHI.