if (Term->getSuccessor(i) == Succ)
return i;
}
- return 0;
}
/// SplitEdge - Split the edge connecting specified block. Pass P must
if (DominatorTree *DT = P->getAnalysisIfAvailable<DominatorTree>()) {
// Old dominates New. New node dominates all other nodes dominated by Old.
- DomTreeNode *OldNode = DT->getNode(Old);
- std::vector<DomTreeNode *> Children;
- for (DomTreeNode::iterator I = OldNode->begin(), E = OldNode->end();
- I != E; ++I)
- Children.push_back(*I);
+ if (DomTreeNode *OldNode = DT->getNode(Old)) {
+ std::vector<DomTreeNode *> Children;
+ for (DomTreeNode::iterator I = OldNode->begin(), E = OldNode->end();
+ I != E; ++I)
+ Children.push_back(*I);
DomTreeNode *NewNode = DT->addNewBlock(New,Old);
for (std::vector<DomTreeNode *>::iterator I = Children.begin(),
E = Children.end(); I != E; ++I)
DT->changeImmediateDominator(*I, NewNode);
+ }
}
return New;
/// of the edges being split is an exit of a loop with other exits).
///
BasicBlock *llvm::SplitBlockPredecessors(BasicBlock *BB,
- BasicBlock *const *Preds,
- unsigned NumPreds, const char *Suffix,
- Pass *P) {
+ ArrayRef<BasicBlock*> Preds,
+ const char *Suffix, Pass *P) {
// Create new basic block, insert right before the original block.
BasicBlock *NewBB = BasicBlock::Create(BB->getContext(), BB->getName()+Suffix,
BB->getParent(), BB);
BranchInst *BI = BranchInst::Create(BB, NewBB);
// Move the edges from Preds to point to NewBB instead of BB.
- for (unsigned i = 0; i != NumPreds; ++i) {
+ for (unsigned i = 0, e = Preds.size(); i != e; ++i) {
// This is slightly more strict than necessary; the minimum requirement
// is that there be no more than one indirectbr branching to BB. And
// all BlockAddress uses would need to be updated.
// node becomes an incoming value for BB's phi node. However, if the Preds
// list is empty, we need to insert dummy entries into the PHI nodes in BB to
// account for the newly created predecessor.
- if (NumPreds == 0) {
+ if (Preds.size() == 0) {
// Insert dummy values as the incoming value.
for (BasicBlock::iterator I = BB->begin(); isa<PHINode>(I); ++I)
cast<PHINode>(I)->addIncoming(UndefValue::get(I->getType()), NewBB);
// Update DominatorTree, LoopInfo, and LCCSA analysis information.
bool HasLoopExit = false;
- UpdateAnalysisInformation(BB, NewBB, ArrayRef<BasicBlock*>(Preds, NumPreds),
- P, HasLoopExit);
+ UpdateAnalysisInformation(BB, NewBB, Preds, P, HasLoopExit);
// Update the PHI nodes in BB with the values coming from NewBB.
- UpdatePHINodes(BB, NewBB, ArrayRef<BasicBlock*>(Preds, NumPreds), BI,
- P, HasLoopExit);
+ UpdatePHINodes(BB, NewBB, Preds, BI, P, HasLoopExit);
return NewBB;
}
// Update the PHI nodes in OrigBB with the values coming from NewBB1.
UpdatePHINodes(OrigBB, NewBB1, Preds, BI1, P, HasLoopExit);
- // Create another basic block for the rest of OrigBB's predecessors.
- BasicBlock *NewBB2 = BasicBlock::Create(OrigBB->getContext(),
- OrigBB->getName() + Suffix2,
- OrigBB->getParent(), OrigBB);
- NewBBs.push_back(NewBB2);
-
- // The new block unconditionally branches to the old block.
- BranchInst *BI2 = BranchInst::Create(OrigBB, NewBB2);
-
// Move the remaining edges from OrigBB to point to NewBB2.
SmallVector<BasicBlock*, 8> NewBB2Preds;
for (pred_iterator i = pred_begin(OrigBB), e = pred_end(OrigBB);
i != e; ) {
BasicBlock *Pred = *i++;
- if (Pred == NewBB1 || Pred == NewBB2 ) continue;
+ if (Pred == NewBB1) continue;
assert(!isa<IndirectBrInst>(Pred->getTerminator()) &&
"Cannot split an edge from an IndirectBrInst");
- Pred->getTerminator()->replaceUsesOfWith(OrigBB, NewBB2);
NewBB2Preds.push_back(Pred);
e = pred_end(OrigBB);
}
- // Update DominatorTree, LoopInfo, and LCCSA analysis information.
- HasLoopExit = false;
- UpdateAnalysisInformation(OrigBB, NewBB2, NewBB2Preds, P, HasLoopExit);
+ BasicBlock *NewBB2 = 0;
+ if (!NewBB2Preds.empty()) {
+ // Create another basic block for the rest of OrigBB's predecessors.
+ NewBB2 = BasicBlock::Create(OrigBB->getContext(),
+ OrigBB->getName() + Suffix2,
+ OrigBB->getParent(), OrigBB);
+ NewBBs.push_back(NewBB2);
- // Update the PHI nodes in OrigBB with the values coming from NewBB2.
- UpdatePHINodes(OrigBB, NewBB2, NewBB2Preds, BI2, P, HasLoopExit);
+ // The new block unconditionally branches to the old block.
+ BranchInst *BI2 = BranchInst::Create(OrigBB, NewBB2);
+
+ // Move the remaining edges from OrigBB to point to NewBB2.
+ for (SmallVectorImpl<BasicBlock*>::iterator
+ i = NewBB2Preds.begin(), e = NewBB2Preds.end(); i != e; ++i)
+ (*i)->getTerminator()->replaceUsesOfWith(OrigBB, NewBB2);
+
+ // Update DominatorTree, LoopInfo, and LCCSA analysis information.
+ HasLoopExit = false;
+ UpdateAnalysisInformation(OrigBB, NewBB2, NewBB2Preds, P, HasLoopExit);
+
+ // Update the PHI nodes in OrigBB with the values coming from NewBB2.
+ UpdatePHINodes(OrigBB, NewBB2, NewBB2Preds, BI2, P, HasLoopExit);
+ }
LandingPadInst *LPad = OrigBB->getLandingPadInst();
Instruction *Clone1 = LPad->clone();
Clone1->setName(Twine("lpad") + Suffix1);
NewBB1->getInstList().insert(NewBB1->getFirstInsertionPt(), Clone1);
- Instruction *Clone2 = LPad->clone();
- Clone2->setName(Twine("lpad") + Suffix2);
- NewBB2->getInstList().insert(NewBB2->getFirstInsertionPt(), Clone2);
-
- // Create a PHI node for the two cloned landingpad instructions.
- PHINode *PN = PHINode::Create(LPad->getType(), 2, "lpad.phi", LPad);
- PN->addIncoming(Clone1, NewBB1);
- PN->addIncoming(Clone2, NewBB2);
- LPad->replaceAllUsesWith(PN);
- LPad->eraseFromParent();
+ if (NewBB2) {
+ Instruction *Clone2 = LPad->clone();
+ Clone2->setName(Twine("lpad") + Suffix2);
+ NewBB2->getInstList().insert(NewBB2->getFirstInsertionPt(), Clone2);
+
+ // Create a PHI node for the two cloned landingpad instructions.
+ PHINode *PN = PHINode::Create(LPad->getType(), 2, "lpad.phi", LPad);
+ PN->addIncoming(Clone1, NewBB1);
+ PN->addIncoming(Clone2, NewBB2);
+ LPad->replaceAllUsesWith(PN);
+ LPad->eraseFromParent();
+ } else {
+ // There is no second clone. Just replace the landing pad with the first
+ // clone.
+ LPad->replaceAllUsesWith(Clone1);
+ LPad->eraseFromParent();
+ }
}
/// FindFunctionBackedges - Analyze the specified function to find all of the
projects / oota-llvm.git / blobdiff