//
// The LLVM Compiler Infrastructure
//
-// This file was developed by the LLVM research group and is distributed under
-// the University of Illinois Open Source License. See LICENSE.TXT for details.
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
/// invalidating the SSA information for the value. It returns the pointer to
/// the alloca inserted to create a stack slot for I.
///
-AllocaInst* llvm::DemoteRegToStack(Instruction &I, bool VolatileLoads) {
- if (I.use_empty()) return 0; // nothing to do!
+AllocaInst* llvm::DemoteRegToStack(Instruction &I, bool VolatileLoads,
+ Instruction *AllocaPoint) {
+ if (I.use_empty()) {
+ I.eraseFromParent();
+ return 0;
+ }
// Create a stack slot to hold the value.
- Function *F = I.getParent()->getParent();
- AllocaInst *Slot = new AllocaInst(I.getType(), 0, I.getName(),
- F->getEntryBlock().begin());
+ AllocaInst *Slot;
+ if (AllocaPoint) {
+ Slot = new AllocaInst(I.getType(), 0,
+ I.getName()+".reg2mem", AllocaPoint);
+ } else {
+ Function *F = I.getParent()->getParent();
+ Slot = new AllocaInst(I.getType(), 0, I.getName()+".reg2mem",
+ F->getEntryBlock().begin());
+ }
// Change all of the users of the instruction to read from the stack slot
// instead.
Value *&V = Loads[PN->getIncomingBlock(i)];
if (V == 0) {
// Insert the load into the predecessor block
- V = new LoadInst(Slot, I.getName()+".reload", VolatileLoads,
+ V = new LoadInst(Slot, I.getName()+".reload", VolatileLoads,
PN->getIncomingBlock(i)->getTerminator());
}
PN->setIncomingValue(i, V);
/// DemotePHIToStack - This function takes a virtual register computed by a phi
/// node and replaces it with a slot in the stack frame, allocated via alloca.
/// The phi node is deleted and it returns the pointer to the alloca inserted.
-AllocaInst* llvm::DemotePHIToStack(PHINode *P) {
+AllocaInst* llvm::DemotePHIToStack(PHINode *P, Instruction *AllocaPoint) {
if (P->use_empty()) {
- P->eraseFromParent();
- return 0;
+ P->eraseFromParent();
+ return 0;
}
-
+
// Create a stack slot to hold the value.
- Function *F = P->getParent()->getParent();
- AllocaInst *Slot = new AllocaInst(P->getType(), 0, P->getName(),
- F->getEntryBlock().begin());
-
+ AllocaInst *Slot;
+ if (AllocaPoint) {
+ Slot = new AllocaInst(P->getType(), 0,
+ P->getName()+".reg2mem", AllocaPoint);
+ } else {
+ Function *F = P->getParent()->getParent();
+ Slot = new AllocaInst(P->getType(), 0, P->getName()+".reg2mem",
+ F->getEntryBlock().begin());
+ }
+
// Iterate over each operand, insert store in each predecessor.
for (unsigned i = 0, e = P->getNumIncomingValues(); i < e; ++i) {
if (InvokeInst *II = dyn_cast<InvokeInst>(P->getIncomingValue(i))) {
- assert(II->getParent() != P->getIncomingBlock(i) &&
- "Invoke edge not supported yet");
+ assert(II->getParent() != P->getIncomingBlock(i) &&
+ "Invoke edge not supported yet"); (void)II;
}
- new StoreInst(P->getIncomingValue(i), Slot,
+ new StoreInst(P->getIncomingValue(i), Slot,
P->getIncomingBlock(i)->getTerminator());
}
-
+
// Insert load in place of the phi and replace all uses.
- BasicBlock::iterator InsertPt;
- for (InsertPt = P->getParent()->getInstList().begin();
- isa<PHINode>(InsertPt); ++InsertPt)
- ; /*noop */
Value *V = new LoadInst(Slot, P->getName()+".reload", P);
P->replaceAllUsesWith(V);
-
+
// Delete phi.
P->eraseFromParent();
-
+
return Slot;
}