13 // 1. Collect the set of headers H of the SCC.
14 // 2. Collect the set of predecessors P of these headers. These may be inside as
22 // INPUT CFG: The blocks A and B form an irreducible loop with two headers.
56 // headers). The function also moves every PHINode in an outgoing block to the
117                                 SetVector<BasicBlock *> &Headers) {  in INITIALIZE_PASS_DEPENDENCY()
136     if (Headers.count(Child->getHeader())) {  in INITIALIZE_PASS_DEPENDENCY()
161 // Given a set of blocks and headers in an irreducible SCC, convert it into a
167                                       SetVector<BasicBlock *> &Headers) {  in createNaturalLoopInternal()  argument
169   // All headers are part of the SCC  in createNaturalLoopInternal()
170   for (auto *H : Headers) {  in createNaturalLoopInternal()
176   for (auto *H : Headers) {  in createNaturalLoopInternal()
191   // predecessors to the headers.  in createNaturalLoopInternal()
194   CreateControlFlowHub(&DTU, GuardBlocks, Predecessors, Headers, "irr");  in createNaturalLoopInternal()
233   reconnectChildLoops(LI, ParentLoop, NewLoop, Blocks, Headers);  in createNaturalLoopInternal()
255                               SetVector<BasicBlock *> &Headers) {  in createNaturalLoop()  argument
256   createNaturalLoopInternal(LI, DT, nullptr, Blocks, Headers);  in createNaturalLoop()
261                               SetVector<BasicBlock *> &Headers) {  in createNaturalLoop()  argument
262   createNaturalLoopInternal(LI, DT, &L, Blocks, Headers);  in createNaturalLoop()
285     // match. So we discover the headers using the reverse of the block order.  in makeReducible()
286     SetVector<BasicBlock *> Headers;  in makeReducible()  local
287     LLVM_DEBUG(dbgs() << "Found headers:");  in makeReducible()
295           Headers.insert(BB);  in makeReducible()
302     if (Headers.size() == 1) {  in makeReducible()
303       assert(LI.isLoopHeader(Headers.front()));  in makeReducible()
307     createNaturalLoop(LI, DT, G, Blocks, Headers);  in makeReducible()