diff options
| -rw-r--r-- | lib/CodeGen/MachineBlockPlacement.cpp | 28 |
1 files changed, 26 insertions, 2 deletions
diff --git a/lib/CodeGen/MachineBlockPlacement.cpp b/lib/CodeGen/MachineBlockPlacement.cpp index bd50ac3a4d..6c8390fee6 100644 --- a/lib/CodeGen/MachineBlockPlacement.cpp +++ b/lib/CodeGen/MachineBlockPlacement.cpp @@ -377,6 +377,23 @@ MachineBasicBlock *MachineBlockPlacement::selectBestSuccessor( return BestSucc; } +namespace { +/// \brief Predicate struct to detect blocks already placed. +class IsBlockPlaced { + const BlockChain &PlacedChain; + const BlockToChainMapType &BlockToChain; + +public: + IsBlockPlaced(const BlockChain &PlacedChain, + const BlockToChainMapType &BlockToChain) + : PlacedChain(PlacedChain), BlockToChain(BlockToChain) {} + + bool operator()(MachineBasicBlock *BB) const { + return BlockToChain.lookup(BB) == &PlacedChain; + } +}; +} + /// \brief Select the best block from a worklist. /// /// This looks through the provided worklist as a list of candidate basic @@ -390,13 +407,20 @@ MachineBasicBlock *MachineBlockPlacement::selectBestSuccessor( MachineBasicBlock *MachineBlockPlacement::selectBestCandidateBlock( BlockChain &Chain, SmallVectorImpl<MachineBasicBlock *> &WorkList, const BlockFilterSet *BlockFilter) { + // Once we need to walk the worklist looking for a candidate, cleanup the + // worklist of already placed entries. + // FIXME: If this shows up on profiles, it could be folded (at the cost of + // some code complexity) into the loop below. + WorkList.erase(std::remove_if(WorkList.begin(), WorkList.end(), + IsBlockPlaced(Chain, BlockToChain)), + WorkList.end()); + MachineBasicBlock *BestBlock = 0; BlockFrequency BestFreq; for (SmallVectorImpl<MachineBasicBlock *>::iterator WBI = WorkList.begin(), WBE = WorkList.end(); WBI != WBE; ++WBI) { - if (BlockFilter && !BlockFilter->count(*WBI)) - continue; + assert(!BlockFilter || BlockFilter->count(*WBI)); BlockChain &SuccChain = *BlockToChain[*WBI]; if (&SuccChain == &Chain) { DEBUG(dbgs() << " " << getBlockName(*WBI) |