// Loop through all of our successors and make sure they know that one
// of their predecessors is going away.
- for (unsigned i = 0, e = BBTerm->getNumSuccessors(); i != e; ++i)
- BBTerm->getSuccessor(i)->removePredecessor(BB);
+ for (BasicBlock *Succ : BBTerm->successors())
+ Succ->removePredecessor(BB);
// Zap all the instructions in the block.
while (!BB->empty()) {
/// any single-entry PHI nodes in it, fold them away. This handles the case
/// when all entries to the PHI nodes in a block are guaranteed equal, such as
/// when the block has exactly one predecessor.
-void llvm::FoldSingleEntryPHINodes(BasicBlock *BB, AliasAnalysis *AA,
+void llvm::FoldSingleEntryPHINodes(BasicBlock *BB,
MemoryDependenceAnalysis *MemDep) {
if (!isa<PHINode>(BB->begin())) return;
/// MergeBlockIntoPredecessor - Attempts to merge a block into its predecessor,
/// if possible. The return value indicates success or failure.
bool llvm::MergeBlockIntoPredecessor(BasicBlock *BB, DominatorTree *DT,
- LoopInfo *LI, AliasAnalysis *AA,
+ LoopInfo *LI,
MemoryDependenceAnalysis *MemDep) {
// Don't merge away blocks who have their address taken.
if (BB->hasAddressTaken()) return false;
// Don't break self-loops.
if (PredBB == BB) return false;
- // Don't break invokes.
- if (isa<InvokeInst>(PredBB->getTerminator())) return false;
+ // Don't break unwinding instructions.
+ if (PredBB->getTerminator()->isExceptional())
+ return false;
succ_iterator SI(succ_begin(PredBB)), SE(succ_end(PredBB));
BasicBlock *OnlySucc = BB;
// Begin by getting rid of unneeded PHIs.
if (isa<PHINode>(BB->front()))
- FoldSingleEntryPHINodes(BB, AA, MemDep);
+ FoldSingleEntryPHINodes(BB, MemDep);
// Delete the unconditional branch from the predecessor...
PredBB->getInstList().pop_back();
// block.
assert(SP == BB && "CFG broken");
SP = nullptr;
- return SplitBlock(Succ, Succ->begin(), DT, LI);
+ return SplitBlock(Succ, &Succ->front(), DT, LI);
}
// Otherwise, if BB has a single successor, split it at the bottom of the
///
BasicBlock *llvm::SplitBlock(BasicBlock *Old, Instruction *SplitPt,
DominatorTree *DT, LoopInfo *LI) {
- BasicBlock::iterator SplitIt = SplitPt;
- while (isa<PHINode>(SplitIt) || isa<LandingPadInst>(SplitIt))
+ BasicBlock::iterator SplitIt = SplitPt->getIterator();
+ while (isa<PHINode>(SplitIt) || SplitIt->isEHPad())
++SplitIt;
BasicBlock *New = Old->splitBasicBlock(SplitIt, Old->getName()+".split");
/// from NewBB. This also updates AliasAnalysis, if available.
static void UpdatePHINodes(BasicBlock *OrigBB, BasicBlock *NewBB,
ArrayRef<BasicBlock *> Preds, BranchInst *BI,
- AliasAnalysis *AA, bool HasLoopExit) {
+ bool HasLoopExit) {
// Otherwise, create a new PHI node in NewBB for each PHI node in OrigBB.
SmallPtrSet<BasicBlock *, 16> PredSet(Preds.begin(), Preds.end());
for (BasicBlock::iterator I = OrigBB->begin(); isa<PHINode>(I); ) {
///
BasicBlock *llvm::SplitBlockPredecessors(BasicBlock *BB,
ArrayRef<BasicBlock *> Preds,
- const char *Suffix, AliasAnalysis *AA,
- DominatorTree *DT, LoopInfo *LI,
- bool PreserveLCSSA) {
+ const char *Suffix, DominatorTree *DT,
+ LoopInfo *LI, bool PreserveLCSSA) {
+ // Do not attempt to split that which cannot be split.
+ if (!BB->canSplitPredecessors())
+ return nullptr;
+
// For the landingpads we need to act a bit differently.
// Delegate this work to the SplitLandingPadPredecessors.
if (BB->isLandingPad()) {
SmallVector<BasicBlock*, 2> NewBBs;
std::string NewName = std::string(Suffix) + ".split-lp";
- SplitLandingPadPredecessors(BB, Preds, Suffix, NewName.c_str(),
- NewBBs, AA, DT, LI, PreserveLCSSA);
+ SplitLandingPadPredecessors(BB, Preds, Suffix, NewName.c_str(), NewBBs, DT,
+ LI, PreserveLCSSA);
return NewBBs[0];
}
HasLoopExit);
// Update the PHI nodes in BB with the values coming from NewBB.
- UpdatePHINodes(BB, NewBB, Preds, BI, AA, HasLoopExit);
+ UpdatePHINodes(BB, NewBB, Preds, BI, HasLoopExit);
return NewBB;
}
ArrayRef<BasicBlock *> Preds,
const char *Suffix1, const char *Suffix2,
SmallVectorImpl<BasicBlock *> &NewBBs,
- AliasAnalysis *AA, DominatorTree *DT,
- LoopInfo *LI, bool PreserveLCSSA) {
+ DominatorTree *DT, LoopInfo *LI,
+ bool PreserveLCSSA) {
assert(OrigBB->isLandingPad() && "Trying to split a non-landing pad!");
// Create a new basic block for OrigBB's predecessors listed in Preds. Insert
HasLoopExit);
// Update the PHI nodes in OrigBB with the values coming from NewBB1.
- UpdatePHINodes(OrigBB, NewBB1, Preds, BI1, AA, HasLoopExit);
+ UpdatePHINodes(OrigBB, NewBB1, Preds, BI1, HasLoopExit);
// Move the remaining edges from OrigBB to point to NewBB2.
SmallVector<BasicBlock*, 8> NewBB2Preds;
PreserveLCSSA, HasLoopExit);
// Update the PHI nodes in OrigBB with the values coming from NewBB2.
- UpdatePHINodes(OrigBB, NewBB2, NewBB2Preds, BI2, AA, HasLoopExit);
+ UpdatePHINodes(OrigBB, NewBB2, NewBB2Preds, BI2, HasLoopExit);
}
LandingPadInst *LPad = OrigBB->getLandingPadInst();
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);
+ // Create a PHI node for the two cloned landingpad instructions only
+ // if the original landingpad instruction has some uses.
+ if (!LPad->use_empty()) {
+ assert(!LPad->getType()->isTokenTy() &&
+ "Split cannot be applied if LPad is token type. Otherwise an "
+ "invalid PHINode of token type would be created.");
+ 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
// return instruction.
V = BCI->getOperand(0);
NewBC = BCI->clone();
- Pred->getInstList().insert(NewRet, NewBC);
+ Pred->getInstList().insert(NewRet->getIterator(), NewBC);
*i = NewBC;
}
if (PHINode *PN = dyn_cast<PHINode>(V)) {
MDNode *BranchWeights,
DominatorTree *DT) {
BasicBlock *Head = SplitBefore->getParent();
- BasicBlock *Tail = Head->splitBasicBlock(SplitBefore);
+ BasicBlock *Tail = Head->splitBasicBlock(SplitBefore->getIterator());
TerminatorInst *HeadOldTerm = Head->getTerminator();
LLVMContext &C = Head->getContext();
BasicBlock *ThenBlock = BasicBlock::Create(C, "", Head->getParent(), Tail);
TerminatorInst **ElseTerm,
MDNode *BranchWeights) {
BasicBlock *Head = SplitBefore->getParent();
- BasicBlock *Tail = Head->splitBasicBlock(SplitBefore);
+ BasicBlock *Tail = Head->splitBasicBlock(SplitBefore->getIterator());
TerminatorInst *HeadOldTerm = Head->getTerminator();
LLVMContext &C = Head->getContext();
BasicBlock *ThenBlock = BasicBlock::Create(C, "", Head->getParent(), Tail);
projects / oota-llvm.git / blobdiff