Author: Roman Lebedev Date: 2020-12-14T20:14:31+03:00 New Revision: e8360a8e1e78edded1f6e95a7fdbac55fe42285f
URL: https://github.com/llvm/llvm-project/commit/e8360a8e1e78edded1f6e95a7fdbac55fe42285f DIFF: https://github.com/llvm/llvm-project/commit/e8360a8e1e78edded1f6e95a7fdbac55fe42285f.diff LOG: [NFC][SimplifyCFG] FoldBranchToCommonDest(): pull out 'common successor' into a variable Makes it easier to use it elsewhere Added: Modified: llvm/lib/Transforms/Utils/SimplifyCFG.cpp Removed: ################################################################################ diff --git a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp b/llvm/lib/Transforms/Utils/SimplifyCFG.cpp index f2b7ffd67057..8f0ed2c46207 100644 --- a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp +++ b/llvm/lib/Transforms/Utils/SimplifyCFG.cpp @@ -2944,12 +2944,16 @@ bool llvm::FoldBranchToCommonDest(BranchInst *BI, MemorySSAUpdater *MSSAU, // and non-PHI uses will become invalid. FormTrivialSSAPHI(BB); + BasicBlock *UniqueSucc = + BI->isConditional() + ? (PBI->getSuccessor(0) == BB ? TrueDest : FalseDest) + : TrueDest; + // Before cloning instructions, notify the successor basic block that it // is about to have a new predecessor. This will update PHI nodes, // which will allow us to update live-out uses of bonus instructions. if (BI->isConditional()) - AddPredecessorToBlock(PBI->getSuccessor(0) == BB ? TrueDest : FalseDest, - PredBlock, BB, MSSAU); + AddPredecessorToBlock(UniqueSucc, PredBlock, BB, MSSAU); // If we have bonus instructions, clone them into the predecessor block. // Note that there may be multiple predecessor blocks, so we cannot move @@ -3011,7 +3015,7 @@ bool llvm::FoldBranchToCommonDest(BranchInst *BI, MemorySSAUpdater *MSSAU, if (PBI->getSuccessor(0) == BB) { if (HasWeights) { // PBI: br i1 %x, BB, FalseDest - // BI: br i1 %y, TrueDest, FalseDest + // BI: br i1 %y, UniqueSucc, FalseDest // TrueWeight is TrueWeight for PBI * TrueWeight for BI. NewWeights.push_back(PredTrueWeight * SuccTrueWeight); // FalseWeight is FalseWeight for PBI * TotalWeight for BI + @@ -3022,12 +3026,12 @@ bool llvm::FoldBranchToCommonDest(BranchInst *BI, MemorySSAUpdater *MSSAU, (SuccFalseWeight + SuccTrueWeight) + PredTrueWeight * SuccFalseWeight); } - PBI->setSuccessor(0, TrueDest); + PBI->setSuccessor(0, UniqueSucc); } if (PBI->getSuccessor(1) == BB) { if (HasWeights) { // PBI: br i1 %x, TrueDest, BB - // BI: br i1 %y, TrueDest, FalseDest + // BI: br i1 %y, TrueDest, UniqueSucc // TrueWeight is TrueWeight for PBI * TotalWeight for BI + // FalseWeight for PBI * TrueWeight for BI. NewWeights.push_back(PredTrueWeight * @@ -3036,7 +3040,7 @@ bool llvm::FoldBranchToCommonDest(BranchInst *BI, MemorySSAUpdater *MSSAU, // FalseWeight is FalseWeight for PBI * FalseWeight for BI. NewWeights.push_back(PredFalseWeight * SuccFalseWeight); } - PBI->setSuccessor(1, FalseDest); + PBI->setSuccessor(1, UniqueSucc); } if (NewWeights.size() == 2) { // Halve the weights if any of them cannot fit in an uint32_t @@ -3054,7 +3058,7 @@ bool llvm::FoldBranchToCommonDest(BranchInst *BI, MemorySSAUpdater *MSSAU, PHIs[i]->getIncomingValueForBlock(PBI->getParent())); assert(PBI_C->getType()->isIntegerTy(1)); Instruction *MergedCond = nullptr; - if (PBI->getSuccessor(0) == TrueDest) { + if (PBI->getSuccessor(0) == UniqueSucc) { // Create (PBI_Cond and PBI_C) or (!PBI_Cond and BI_Value) // PBI_C is true: PBI_Cond or (!PBI_Cond and BI_Value) // is false: !PBI_Cond and BI_Value @@ -3083,13 +3087,13 @@ bool llvm::FoldBranchToCommonDest(BranchInst *BI, MemorySSAUpdater *MSSAU, PHIs[i]->setIncomingValueForBlock(PBI->getParent(), MergedCond); } - // PBI is changed to branch to TrueDest below. Remove itself from + // PBI is changed to branch to UniqueSucc below. Remove itself from // potential phis from all other successors. if (MSSAU) - MSSAU->changeCondBranchToUnconditionalTo(PBI, TrueDest); + MSSAU->changeCondBranchToUnconditionalTo(PBI, UniqueSucc); // Change PBI from Conditional to Unconditional. - BranchInst *New_PBI = BranchInst::Create(TrueDest, PBI); + BranchInst *New_PBI = BranchInst::Create(UniqueSucc, PBI); EraseTerminatorAndDCECond(PBI, MSSAU); PBI = New_PBI; } _______________________________________________ llvm-branch-commits mailing list llvm-branch-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-branch-commits
