// Loop through all of our successors and make sure they know that one
// of their predecessors is going away.
// 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);
/// 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.
/// 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.
/// 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,
/// 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,
MemoryDependenceAnalysis *MemDep) {
// Don't merge away blocks who have their address taken.
if (BB->hasAddressTaken()) return false;
MemoryDependenceAnalysis *MemDep) {
// Don't merge away blocks who have their address taken.
if (BB->hasAddressTaken()) return false;
succ_iterator SI(succ_begin(PredBB)), SE(succ_end(PredBB));
BasicBlock *OnlySucc = BB;
succ_iterator SI(succ_begin(PredBB)), SE(succ_end(PredBB));
BasicBlock *OnlySucc = BB;
BasicBlock *llvm::SplitBlock(BasicBlock *Old, Instruction *SplitPt,
DominatorTree *DT, LoopInfo *LI) {
BasicBlock::iterator SplitIt = SplitPt;
BasicBlock *llvm::SplitBlock(BasicBlock *Old, Instruction *SplitPt,
DominatorTree *DT, LoopInfo *LI) {
BasicBlock::iterator SplitIt = SplitPt;
/// from NewBB. This also updates AliasAnalysis, if available.
static void UpdatePHINodes(BasicBlock *OrigBB, BasicBlock *NewBB,
ArrayRef<BasicBlock *> Preds, BranchInst *BI,
/// from NewBB. This also updates AliasAnalysis, if available.
static void UpdatePHINodes(BasicBlock *OrigBB, BasicBlock *NewBB,
ArrayRef<BasicBlock *> Preds, BranchInst *BI,
// 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); ) {
// 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); ) {
// Create the new PHI node, insert it into NewBB at the end of the block
PHINode *NewPHI =
PHINode::Create(PN->getType(), Preds.size(), PN->getName() + ".ph", BI);
// Create the new PHI node, insert it into NewBB at the end of the block
PHINode *NewPHI =
PHINode::Create(PN->getType(), Preds.size(), PN->getName() + ".ph", BI);
// NOTE! This loop walks backwards for a reason! First off, this minimizes
// the cost of removal if we end up removing a large number of values, and
// NOTE! This loop walks backwards for a reason! First off, this minimizes
// the cost of removal if we end up removing a large number of values, and
///
BasicBlock *llvm::SplitBlockPredecessors(BasicBlock *BB,
ArrayRef<BasicBlock *> Preds,
///
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";
// 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);
- UpdatePHINodes(BB, NewBB, Preds, BI, AA, HasLoopExit);
+ UpdatePHINodes(BB, NewBB, Preds, BI, HasLoopExit);
ArrayRef<BasicBlock *> Preds,
const char *Suffix1, const char *Suffix2,
SmallVectorImpl<BasicBlock *> &NewBBs,
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
assert(OrigBB->isLandingPad() && "Trying to split a non-landing pad!");
// Create a new basic block for OrigBB's predecessors listed in Preds. Insert
- 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;
// 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.
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);