19 /// of blocks with a single entry and no branches back to that entry. A region
37 /// use the "label" helper for the blocks we absolutely must and no others. We
81 // Calculates reachability in a region. Ignores branches to blocks outside of
86   ReachabilityGraph(MachineBasicBlock *Entry, const BlockSet &Blocks)  in ReachabilityGraph()  argument
87       : Entry(Entry), Blocks(Blocks) {  in ReachabilityGraph()
90     for (auto *MBB : Blocks) {  in ReachabilityGraph()
109   // "Loopers" are blocks that are in a loop. We detect these by finding blocks
113   // Get all blocks that are loop entries.
116   // Get all blocks that enter a particular loop from outside.
126   const BlockSet &Blocks;  member in __anon63cd76cd0111::ReachabilityGraph
131   bool inRegion(MachineBasicBlock *MBB) const { return Blocks.count(MBB); }  in inRegion()
133   // Maps a block to all the other blocks it can reach.
143     for (auto *MBB : Blocks) {  in calculate()
167     // Blocks that can return to themselves are in a loop.  in calculate()
168     for (auto *MBB : Blocks) {  in calculate()
175     // Find the loop entries - loopers reachable from blocks not in that loop -  in calculate()
176     // and those outside blocks that reach them, the "loop enterers".  in calculate()
190 // Finds the blocks in a single-entry loop, given the loop entry and the
191 // list of blocks that enter the loop.
199   BlockSet &getBlocks() { return Blocks; }  in getBlocks()
205   BlockSet Blocks;  member in __anon63cd76cd0111::LoopBlocks
208     // Going backwards from the loop entry, if we ignore the blocks entering  in calculate()
209     // from outside, we will traverse all the blocks in the loop.  in calculate()
212     Blocks.insert(Entry);  in calculate()
223       if (Blocks.insert(MBB).second) {  in calculate()
240   bool processRegion(MachineBasicBlock *Entry, BlockSet &Blocks,
243   void makeSingleEntryLoop(BlockSet &Entries, BlockSet &Blocks,
252     MachineBasicBlock *Entry, BlockSet &Blocks, MachineFunction &MF) {  in processRegion()  argument
257     ReachabilityGraph Graph(Entry, Blocks);  in processRegion()
284       // a group of blocks all of whom can reach each other. (We'll see the  in processRegion()
298         makeSingleEntryLoop(MutualLoopEntries, Blocks, MF, Graph);  in processRegion()
318       // to the graph are to add blocks on the way to a loop entry. As the  in processRegion()
333 // a helper variable. Also updates Blocks with any new blocks created, so
334 // that we properly track all the blocks in the region. But this does not update
338     BlockSet &Entries, BlockSet &Blocks, MachineFunction &MF,  in makeSingleEntryLoop()  argument
361   Blocks.insert(Dispatch);  in makeSingleEntryLoop()
389   // the bad blocks. For simplicity, we just introduce a new block for every  in makeSingleEntryLoop()
425   // We need to create at most two routing blocks per entry: one for  in makeSingleEntryLoop()
449       Blocks.insert(Routing);  in makeSingleEntryLoop()
548     // Now we've inserted dispatch blocks, some register uses can have incoming  in runOnMachineFunction()