diff options
Diffstat (limited to 'llvm/lib/Transforms/Utils/SimplifyCFG.cpp')
-rw-r--r-- | llvm/lib/Transforms/Utils/SimplifyCFG.cpp | 75 |
1 files changed, 39 insertions, 36 deletions
diff --git a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp b/llvm/lib/Transforms/Utils/SimplifyCFG.cpp index 668e22f46f4..3846b21c502 100644 --- a/llvm/lib/Transforms/Utils/SimplifyCFG.cpp +++ b/llvm/lib/Transforms/Utils/SimplifyCFG.cpp @@ -167,6 +167,7 @@ class SimplifyCFGOpt { const TargetTransformInfo &TTI; const DataLayout &DL; unsigned BonusInstThreshold; + AssumptionCache *AC; SmallPtrSetImpl<BasicBlock *> *LoopHeaders; Value *isValueEqualityComparison(TerminatorInst *TI); BasicBlock *GetValueEqualityComparisonCases( @@ -190,9 +191,9 @@ class SimplifyCFGOpt { public: SimplifyCFGOpt(const TargetTransformInfo &TTI, const DataLayout &DL, - unsigned BonusInstThreshold, + unsigned BonusInstThreshold, AssumptionCache *AC, SmallPtrSetImpl<BasicBlock *> *LoopHeaders) - : TTI(TTI), DL(DL), BonusInstThreshold(BonusInstThreshold), + : TTI(TTI), DL(DL), BonusInstThreshold(BonusInstThreshold), AC(AC), LoopHeaders(LoopHeaders) {} bool run(BasicBlock *BB); @@ -3479,7 +3480,8 @@ static bool SimplifyIndirectBrOnSelect(IndirectBrInst *IBI, SelectInst *SI) { /// the PHI, merging the third icmp into the switch. static bool TryToSimplifyUncondBranchWithICmpInIt( ICmpInst *ICI, IRBuilder<> &Builder, const DataLayout &DL, - const TargetTransformInfo &TTI, unsigned BonusInstThreshold) { + const TargetTransformInfo &TTI, unsigned BonusInstThreshold, + AssumptionCache *AC) { BasicBlock *BB = ICI->getParent(); // If the block has any PHIs in it or the icmp has multiple uses, it is too @@ -3514,7 +3516,7 @@ static bool TryToSimplifyUncondBranchWithICmpInIt( ICI->eraseFromParent(); } // BB is now empty, so it is likely to simplify away. - return SimplifyCFG(BB, TTI, BonusInstThreshold) | true; + return SimplifyCFG(BB, TTI, BonusInstThreshold, AC) | true; } // Ok, the block is reachable from the default dest. If the constant we're @@ -3530,7 +3532,7 @@ static bool TryToSimplifyUncondBranchWithICmpInIt( ICI->replaceAllUsesWith(V); ICI->eraseFromParent(); // BB is now empty, so it is likely to simplify away. - return SimplifyCFG(BB, TTI, BonusInstThreshold) | true; + return SimplifyCFG(BB, TTI, BonusInstThreshold, AC) | true; } // The use of the icmp has to be in the 'end' block, by the only PHI node in @@ -4327,16 +4329,17 @@ static bool TurnSwitchRangeIntoICmp(SwitchInst *SI, IRBuilder<> &Builder) { /// Compute masked bits for the condition of a switch /// and use it to remove dead cases. -static bool EliminateDeadSwitchCases(SwitchInst *SI, const DataLayout &DL) { +static bool EliminateDeadSwitchCases(SwitchInst *SI, AssumptionCache *AC, + const DataLayout &DL) { Value *Cond = SI->getCondition(); unsigned Bits = Cond->getType()->getIntegerBitWidth(); APInt KnownZero(Bits, 0), KnownOne(Bits, 0); - computeKnownBits(Cond, KnownZero, KnownOne, DL, 0, SI); + computeKnownBits(Cond, KnownZero, KnownOne, DL, 0, AC, SI); // We can also eliminate cases by determining that their values are outside of // the limited range of the condition based on how many significant (non-sign) // bits are in the condition value. - unsigned ExtraSignBits = ComputeNumSignBits(Cond, DL, 0, SI) - 1; + unsigned ExtraSignBits = ComputeNumSignBits(Cond, DL, 0, AC, SI) - 1; unsigned MaxSignificantBitsInCond = Bits - ExtraSignBits; // Gather dead cases. @@ -4756,7 +4759,7 @@ static void RemoveSwitchAfterSelectConversion(SwitchInst *SI, PHINode *PHI, /// phi nodes in a common successor block with only two different /// constant values, replace the switch with select. static bool SwitchToSelect(SwitchInst *SI, IRBuilder<> &Builder, - const DataLayout &DL, + AssumptionCache *AC, const DataLayout &DL, const TargetTransformInfo &TTI) { Value *const Cond = SI->getCondition(); PHINode *PHI = nullptr; @@ -5503,12 +5506,12 @@ bool SimplifyCFGOpt::SimplifySwitch(SwitchInst *SI, IRBuilder<> &Builder) { // see if that predecessor totally determines the outcome of this switch. if (BasicBlock *OnlyPred = BB->getSinglePredecessor()) if (SimplifyEqualityComparisonWithOnlyPredecessor(SI, OnlyPred, Builder)) - return SimplifyCFG(BB, TTI, BonusInstThreshold) | true; + return SimplifyCFG(BB, TTI, BonusInstThreshold, AC) | true; Value *Cond = SI->getCondition(); if (SelectInst *Select = dyn_cast<SelectInst>(Cond)) if (SimplifySwitchOnSelect(SI, Select)) - return SimplifyCFG(BB, TTI, BonusInstThreshold) | true; + return SimplifyCFG(BB, TTI, BonusInstThreshold, AC) | true; // If the block only contains the switch, see if we can fold the block // away into any preds. @@ -5518,28 +5521,28 @@ bool SimplifyCFGOpt::SimplifySwitch(SwitchInst *SI, IRBuilder<> &Builder) { ++BBI; if (SI == &*BBI) if (FoldValueComparisonIntoPredecessors(SI, Builder)) - return SimplifyCFG(BB, TTI, BonusInstThreshold) | true; + return SimplifyCFG(BB, TTI, BonusInstThreshold, AC) | true; } // Try to transform the switch into an icmp and a branch. if (TurnSwitchRangeIntoICmp(SI, Builder)) - return SimplifyCFG(BB, TTI, BonusInstThreshold) | true; + return SimplifyCFG(BB, TTI, BonusInstThreshold, AC) | true; // Remove unreachable cases. - if (EliminateDeadSwitchCases(SI, DL)) - return SimplifyCFG(BB, TTI, BonusInstThreshold) | true; + if (EliminateDeadSwitchCases(SI, AC, DL)) + return SimplifyCFG(BB, TTI, BonusInstThreshold, AC) | true; - if (SwitchToSelect(SI, Builder, DL, TTI)) - return SimplifyCFG(BB, TTI, BonusInstThreshold) | true; + if (SwitchToSelect(SI, Builder, AC, DL, TTI)) + return SimplifyCFG(BB, TTI, BonusInstThreshold, AC) | true; if (ForwardSwitchConditionToPHI(SI)) - return SimplifyCFG(BB, TTI, BonusInstThreshold) | true; + return SimplifyCFG(BB, TTI, BonusInstThreshold, AC) | true; if (SwitchToLookupTable(SI, Builder, DL, TTI)) - return SimplifyCFG(BB, TTI, BonusInstThreshold) | true; + return SimplifyCFG(BB, TTI, BonusInstThreshold, AC) | true; if (ReduceSwitchRange(SI, Builder, DL, TTI)) - return SimplifyCFG(BB, TTI, BonusInstThreshold) | true; + return SimplifyCFG(BB, TTI, BonusInstThreshold, AC) | true; return false; } @@ -5577,7 +5580,7 @@ bool SimplifyCFGOpt::SimplifyIndirectBr(IndirectBrInst *IBI) { if (SelectInst *SI = dyn_cast<SelectInst>(IBI->getAddress())) { if (SimplifyIndirectBrOnSelect(IBI, SI)) - return SimplifyCFG(BB, TTI, BonusInstThreshold) | true; + return SimplifyCFG(BB, TTI, BonusInstThreshold, AC) | true; } return Changed; } @@ -5686,7 +5689,7 @@ bool SimplifyCFGOpt::SimplifyUncondBranch(BranchInst *BI, ; if (I->isTerminator() && TryToSimplifyUncondBranchWithICmpInIt(ICI, Builder, DL, TTI, - BonusInstThreshold)) + BonusInstThreshold, AC)) return true; } @@ -5704,7 +5707,7 @@ bool SimplifyCFGOpt::SimplifyUncondBranch(BranchInst *BI, // predecessor and use logical operations to update the incoming value // for PHI nodes in common successor. if (FoldBranchToCommonDest(BI, BonusInstThreshold)) - return SimplifyCFG(BB, TTI, BonusInstThreshold) | true; + return SimplifyCFG(BB, TTI, BonusInstThreshold, AC) | true; return false; } @@ -5729,7 +5732,7 @@ bool SimplifyCFGOpt::SimplifyCondBranch(BranchInst *BI, IRBuilder<> &Builder) { // switch. if (BasicBlock *OnlyPred = BB->getSinglePredecessor()) if (SimplifyEqualityComparisonWithOnlyPredecessor(BI, OnlyPred, Builder)) - return SimplifyCFG(BB, TTI, BonusInstThreshold) | true; + return SimplifyCFG(BB, TTI, BonusInstThreshold, AC) | true; // This block must be empty, except for the setcond inst, if it exists. // Ignore dbg intrinsics. @@ -5739,14 +5742,14 @@ bool SimplifyCFGOpt::SimplifyCondBranch(BranchInst *BI, IRBuilder<> &Builder) { ++I; if (&*I == BI) { if (FoldValueComparisonIntoPredecessors(BI, Builder)) - return SimplifyCFG(BB, TTI, BonusInstThreshold) | true; + return SimplifyCFG(BB, TTI, BonusInstThreshold, AC) | true; } else if (&*I == cast<Instruction>(BI->getCondition())) { ++I; // Ignore dbg intrinsics. while (isa<DbgInfoIntrinsic>(I)) ++I; if (&*I == BI && FoldValueComparisonIntoPredecessors(BI, Builder)) - return SimplifyCFG(BB, TTI, BonusInstThreshold) | true; + return SimplifyCFG(BB, TTI, BonusInstThreshold, AC) | true; } } @@ -5773,7 +5776,7 @@ bool SimplifyCFGOpt::SimplifyCondBranch(BranchInst *BI, IRBuilder<> &Builder) { : ConstantInt::getFalse(BB->getContext()); BI->setCondition(CI); RecursivelyDeleteTriviallyDeadInstructions(OldCond); - return SimplifyCFG(BB, TTI, BonusInstThreshold) | true; + return SimplifyCFG(BB, TTI, BonusInstThreshold, AC) | true; } } } @@ -5782,7 +5785,7 @@ bool SimplifyCFGOpt::SimplifyCondBranch(BranchInst *BI, IRBuilder<> &Builder) { // branches to us and one of our successors, fold the comparison into the // predecessor and use logical operations to pick the right destination. if (FoldBranchToCommonDest(BI, BonusInstThreshold)) - return SimplifyCFG(BB, TTI, BonusInstThreshold) | true; + return SimplifyCFG(BB, TTI, BonusInstThreshold, AC) | true; // We have a conditional branch to two blocks that are only reachable // from BI. We know that the condbr dominates the two blocks, so see if @@ -5791,7 +5794,7 @@ bool SimplifyCFGOpt::SimplifyCondBranch(BranchInst *BI, IRBuilder<> &Builder) { if (BI->getSuccessor(0)->getSinglePredecessor()) { if (BI->getSuccessor(1)->getSinglePredecessor()) { if (HoistThenElseCodeToIf(BI, TTI)) - return SimplifyCFG(BB, TTI, BonusInstThreshold) | true; + return SimplifyCFG(BB, TTI, BonusInstThreshold, AC) | true; } else { // If Successor #1 has multiple preds, we may be able to conditionally // execute Successor #0 if it branches to Successor #1. @@ -5799,7 +5802,7 @@ bool SimplifyCFGOpt::SimplifyCondBranch(BranchInst *BI, IRBuilder<> &Builder) { if (Succ0TI->getNumSuccessors() == 1 && Succ0TI->getSuccessor(0) == BI->getSuccessor(1)) if (SpeculativelyExecuteBB(BI, BI->getSuccessor(0), TTI)) - return SimplifyCFG(BB, TTI, BonusInstThreshold) | true; + return SimplifyCFG(BB, TTI, BonusInstThreshold, AC) | true; } } else if (BI->getSuccessor(1)->getSinglePredecessor()) { // If Successor #0 has multiple preds, we may be able to conditionally @@ -5808,7 +5811,7 @@ bool SimplifyCFGOpt::SimplifyCondBranch(BranchInst *BI, IRBuilder<> &Builder) { if (Succ1TI->getNumSuccessors() == 1 && Succ1TI->getSuccessor(0) == BI->getSuccessor(0)) if (SpeculativelyExecuteBB(BI, BI->getSuccessor(1), TTI)) - return SimplifyCFG(BB, TTI, BonusInstThreshold) | true; + return SimplifyCFG(BB, TTI, BonusInstThreshold, AC) | true; } // If this is a branch on a phi node in the current block, thread control @@ -5816,14 +5819,14 @@ bool SimplifyCFGOpt::SimplifyCondBranch(BranchInst *BI, IRBuilder<> &Builder) { if (PHINode *PN = dyn_cast<PHINode>(BI->getCondition())) if (PN->getParent() == BI->getParent()) if (FoldCondBranchOnPHI(BI, DL)) - return SimplifyCFG(BB, TTI, BonusInstThreshold) | true; + return SimplifyCFG(BB, TTI, BonusInstThreshold, AC) | true; // Scan predecessor blocks for conditional branches. for (pred_iterator PI = pred_begin(BB), E = pred_end(BB); PI != E; ++PI) if (BranchInst *PBI = dyn_cast<BranchInst>((*PI)->getTerminator())) if (PBI != BI && PBI->isConditional()) if (SimplifyCondBranchToCondBranch(PBI, BI, DL)) - return SimplifyCFG(BB, TTI, BonusInstThreshold) | true; + return SimplifyCFG(BB, TTI, BonusInstThreshold, AC) | true; // Look for diamond patterns. if (MergeCondStores) @@ -5831,7 +5834,7 @@ bool SimplifyCFGOpt::SimplifyCondBranch(BranchInst *BI, IRBuilder<> &Builder) { if (BranchInst *PBI = dyn_cast<BranchInst>(PrevBB->getTerminator())) if (PBI != BI && PBI->isConditional()) if (mergeConditionalStores(PBI, BI)) - return SimplifyCFG(BB, TTI, BonusInstThreshold) | true; + return SimplifyCFG(BB, TTI, BonusInstThreshold, AC) | true; return false; } @@ -5993,9 +5996,9 @@ bool SimplifyCFGOpt::run(BasicBlock *BB) { /// of the CFG. It returns true if a modification was made. /// bool llvm::SimplifyCFG(BasicBlock *BB, const TargetTransformInfo &TTI, - unsigned BonusInstThreshold, + unsigned BonusInstThreshold, AssumptionCache *AC, SmallPtrSetImpl<BasicBlock *> *LoopHeaders) { return SimplifyCFGOpt(TTI, BB->getModule()->getDataLayout(), - BonusInstThreshold, LoopHeaders) + BonusInstThreshold, AC, LoopHeaders) .run(BB); } |