getExitingBlocks(ExitingBlocks);
if (ExitingBlocks.size() == 1)
return ExitingBlocks[0];
- return 0;
+ return nullptr;
}
/// getExitBlocks - Return all of the successor blocks of this loop. These
getExitBlocks(ExitBlocks);
if (ExitBlocks.size() == 1)
return ExitBlocks[0];
- return 0;
+ return nullptr;
}
/// getExitEdges - Return all pairs of (_inside_block_,_outside_block_).
BlockT *LoopBase<BlockT, LoopT>::getLoopPreheader() const {
// Keep track of nodes outside the loop branching to the header...
BlockT *Out = getLoopPredecessor();
- if (!Out) return 0;
+ if (!Out) return nullptr;
// Make sure there is only one exit out of the preheader.
typedef GraphTraits<BlockT*> BlockTraits;
typename BlockTraits::ChildIteratorType SI = BlockTraits::child_begin(Out);
++SI;
if (SI != BlockTraits::child_end(Out))
- return 0; // Multiple exits from the block, must not be a preheader.
+ return nullptr; // Multiple exits from the block, must not be a preheader.
// The predecessor has exactly one successor, so it is a preheader.
return Out;
template<class BlockT, class LoopT>
BlockT *LoopBase<BlockT, LoopT>::getLoopPredecessor() const {
// Keep track of nodes outside the loop branching to the header...
- BlockT *Out = 0;
+ BlockT *Out = nullptr;
// Loop over the predecessors of the header node...
BlockT *Header = getHeader();
typename InvBlockTraits::NodeType *N = *PI;
if (!contains(N)) { // If the block is not in the loop...
if (Out && Out != N)
- return 0; // Multiple predecessors outside the loop
+ return nullptr; // Multiple predecessors outside the loop
Out = N;
}
}
InvBlockTraits::child_begin(Header);
typename InvBlockTraits::ChildIteratorType PE =
InvBlockTraits::child_end(Header);
- BlockT *Latch = 0;
+ BlockT *Latch = nullptr;
for (; PI != PE; ++PI) {
typename InvBlockTraits::NodeType *N = *PI;
if (contains(N)) {
- if (Latch) return 0;
+ if (Latch) return nullptr;
Latch = N;
}
}
assert((Blocks.empty() || LIB[getHeader()] == this) &&
"Incorrect LI specified for this loop!");
assert(NewBB && "Cannot add a null basic block to the loop!");
- assert(LIB[NewBB] == 0 && "BasicBlock already in the loop!");
+ assert(!LIB[NewBB] && "BasicBlock already in the loop!");
LoopT *L = static_cast<LoopT *>(this);
void LoopBase<BlockT, LoopT>::
replaceChildLoopWith(LoopT *OldChild, LoopT *NewChild) {
assert(OldChild->ParentLoop == this && "This loop is already broken!");
- assert(NewChild->ParentLoop == 0 && "NewChild already has a parent!");
+ assert(!NewChild->ParentLoop && "NewChild already has a parent!");
typename std::vector<LoopT *>::iterator I =
std::find(SubLoops.begin(), SubLoops.end(), OldChild);
assert(I != SubLoops.end() && "OldChild not in loop!");
*I = NewChild;
- OldChild->ParentLoop = 0;
+ OldChild->ParentLoop = nullptr;
NewChild->ParentLoop = static_cast<LoopT *>(this);
}
// A non-header loop shouldn't be reachable from outside the loop,
// though it is permitted if the predecessor is not itself actually
// reachable.
- BlockT *EntryBB = BB->getParent()->begin();
+ BlockT *EntryBB = &BB->getParent()->front();
for (BlockT *CB : depth_first(EntryBB))
for (unsigned i = 0, e = OutsideLoopPreds.size(); i != e; ++i)
assert(CB != OutsideLoopPreds[i] &&
template<class BlockT, class LoopT>
static void discoverAndMapSubloop(LoopT *L, ArrayRef<BlockT*> Backedges,
LoopInfoBase<BlockT, LoopT> *LI,
- DominatorTreeBase<BlockT> &DomTree) {
+ const DominatorTreeBase<BlockT> &DomTree) {
typedef GraphTraits<Inverse<BlockT*> > InvBlockTraits;
unsigned NumBlocks = 0;
L->reserveBlocks(NumBlocks);
}
-namespace {
/// Populate all loop data in a stable order during a single forward DFS.
template<class BlockT, class LoopT>
class PopulateLoopsDFS {
typedef typename BlockTraits::ChildIteratorType SuccIterTy;
LoopInfoBase<BlockT, LoopT> *LI;
- DenseSet<const BlockT *> VisitedBlocks;
- std::vector<std::pair<BlockT*, SuccIterTy> > DFSStack;
-
public:
PopulateLoopsDFS(LoopInfoBase<BlockT, LoopT> *li):
LI(li) {}
protected:
void insertIntoLoop(BlockT *Block);
-
- BlockT *dfsSource() { return DFSStack.back().first; }
- SuccIterTy &dfsSucc() { return DFSStack.back().second; }
- SuccIterTy dfsSuccEnd() { return BlockTraits::child_end(dfsSource()); }
-
- void pushBlock(BlockT *Block) {
- DFSStack.push_back(std::make_pair(Block, BlockTraits::child_begin(Block)));
- }
};
-} // anonymous
/// Top-level driver for the forward DFS within the loop.
template<class BlockT, class LoopT>
void PopulateLoopsDFS<BlockT, LoopT>::traverse(BlockT *EntryBlock) {
- pushBlock(EntryBlock);
- VisitedBlocks.insert(EntryBlock);
- while (!DFSStack.empty()) {
- // Traverse the leftmost path as far as possible.
- while (dfsSucc() != dfsSuccEnd()) {
- BlockT *BB = *dfsSucc();
- ++dfsSucc();
- if (!VisitedBlocks.insert(BB).second)
- continue;
-
- // Push the next DFS successor onto the stack.
- pushBlock(BB);
- }
- // Visit the top of the stack in postorder and backtrack.
- insertIntoLoop(dfsSource());
- DFSStack.pop_back();
- }
+ for (BlockT *BB : post_order(EntryBlock))
+ insertIntoLoop(BB);
}
/// Add a single Block to its ancestor loops in PostOrder. If the block is a
/// insertions per block.
template<class BlockT, class LoopT>
void LoopInfoBase<BlockT, LoopT>::
-Analyze(DominatorTreeBase<BlockT> &DomTree) {
+analyze(const DominatorTreeBase<BlockT> &DomTree) {
// Postorder traversal of the dominator tree.
- DomTreeNodeBase<BlockT>* DomRoot = DomTree.getRootNode();
- for (po_iterator<DomTreeNodeBase<BlockT>*> DomIter = po_begin(DomRoot),
- DomEnd = po_end(DomRoot); DomIter != DomEnd; ++DomIter) {
+ const DomTreeNodeBase<BlockT> *DomRoot = DomTree.getRootNode();
+ for (auto DomNode : post_order(DomRoot)) {
- BlockT *Header = DomIter->getBlock();
+ BlockT *Header = DomNode->getBlock();
SmallVector<BlockT *, 4> Backedges;
// Check each predecessor of the potential loop header.
#endif
}
+template<class BlockT, class LoopT>
+void LoopInfoBase<BlockT, LoopT>::verify() const {
+ DenseSet<const LoopT*> Loops;
+ for (iterator I = begin(), E = end(); I != E; ++I) {
+ assert(!(*I)->getParentLoop() && "Top-level loop has a parent!");
+ (*I)->verifyLoopNest(&Loops);
+ }
+
+ // Verify that blocks are mapped to valid loops.
+#ifndef NDEBUG
+ for (auto &Entry : BBMap) {
+ const BlockT *BB = Entry.first;
+ LoopT *L = Entry.second;
+ assert(Loops.count(L) && "orphaned loop");
+ assert(L->contains(BB) && "orphaned block");
+ }
+#endif
+}
+
} // End llvm namespace
#endif