diff options
4 files changed, 35 insertions, 11 deletions
diff --git a/llvm/include/llvm/Analysis/InstructionSimplify.h b/llvm/include/llvm/Analysis/InstructionSimplify.h index 706bd8000d3..65654b1ba34 100644 --- a/llvm/include/llvm/Analysis/InstructionSimplify.h +++ b/llvm/include/llvm/Analysis/InstructionSimplify.h @@ -212,7 +212,7 @@ namespace llvm { /// SimplifyFCmpInst - Given operands for an FCmpInst, see if we can /// fold the result. If not, this returns null. Value *SimplifyFCmpInst(unsigned Predicate, Value *LHS, Value *RHS, - const DataLayout &DL, + FastMathFlags FMF, const DataLayout &DL, const TargetLibraryInfo *TLI = nullptr, const DominatorTree *DT = nullptr, AssumptionCache *AC = nullptr, diff --git a/llvm/lib/Analysis/InstructionSimplify.cpp b/llvm/lib/Analysis/InstructionSimplify.cpp index 12e406bb1a2..ab5cd01ab63 100644 --- a/llvm/lib/Analysis/InstructionSimplify.cpp +++ b/llvm/lib/Analysis/InstructionSimplify.cpp @@ -3046,7 +3046,8 @@ Value *llvm::SimplifyICmpInst(unsigned Predicate, Value *LHS, Value *RHS, /// SimplifyFCmpInst - Given operands for an FCmpInst, see if we can /// fold the result. If not, this returns null. static Value *SimplifyFCmpInst(unsigned Predicate, Value *LHS, Value *RHS, - const Query &Q, unsigned MaxRecurse) { + FastMathFlags FMF, const Query &Q, + unsigned MaxRecurse) { CmpInst::Predicate Pred = (CmpInst::Predicate)Predicate; assert(CmpInst::isFPPredicate(Pred) && "Not an FP compare!"); @@ -3065,6 +3066,14 @@ static Value *SimplifyFCmpInst(unsigned Predicate, Value *LHS, Value *RHS, if (Pred == FCmpInst::FCMP_TRUE) return ConstantInt::get(GetCompareTy(LHS), 1); + // UNO/ORD predicates can be trivially folded if NaNs are ignored. + if (FMF.noNaNs()) { + if (Pred == FCmpInst::FCMP_UNO) + return ConstantInt::get(GetCompareTy(LHS), 0); + if (Pred == FCmpInst::FCMP_ORD) + return ConstantInt::get(GetCompareTy(LHS), 1); + } + // fcmp pred x, undef and fcmp pred undef, x // fold to true if unordered, false if ordered if (isa<UndefValue>(LHS) || isa<UndefValue>(RHS)) { @@ -3151,12 +3160,12 @@ static Value *SimplifyFCmpInst(unsigned Predicate, Value *LHS, Value *RHS, } Value *llvm::SimplifyFCmpInst(unsigned Predicate, Value *LHS, Value *RHS, - const DataLayout &DL, + FastMathFlags FMF, const DataLayout &DL, const TargetLibraryInfo *TLI, const DominatorTree *DT, AssumptionCache *AC, const Instruction *CxtI) { - return ::SimplifyFCmpInst(Predicate, LHS, RHS, Query(DL, TLI, DT, AC, CxtI), - RecursionLimit); + return ::SimplifyFCmpInst(Predicate, LHS, RHS, FMF, + Query(DL, TLI, DT, AC, CxtI), RecursionLimit); } /// SimplifyWithOpReplaced - See if V simplifies when its operand Op is @@ -3670,7 +3679,7 @@ static Value *SimplifyCmpInst(unsigned Predicate, Value *LHS, Value *RHS, const Query &Q, unsigned MaxRecurse) { if (CmpInst::isIntPredicate((CmpInst::Predicate)Predicate)) return SimplifyICmpInst(Predicate, LHS, RHS, Q, MaxRecurse); - return SimplifyFCmpInst(Predicate, LHS, RHS, Q, MaxRecurse); + return SimplifyFCmpInst(Predicate, LHS, RHS, FastMathFlags(), Q, MaxRecurse); } Value *llvm::SimplifyCmpInst(unsigned Predicate, Value *LHS, Value *RHS, @@ -3900,9 +3909,9 @@ Value *llvm::SimplifyInstruction(Instruction *I, const DataLayout &DL, I->getOperand(1), DL, TLI, DT, AC, I); break; case Instruction::FCmp: - Result = - SimplifyFCmpInst(cast<FCmpInst>(I)->getPredicate(), I->getOperand(0), - I->getOperand(1), DL, TLI, DT, AC, I); + Result = SimplifyFCmpInst(cast<FCmpInst>(I)->getPredicate(), + I->getOperand(0), I->getOperand(1), + I->getFastMathFlags(), DL, TLI, DT, AC, I); break; case Instruction::Select: Result = SimplifySelectInst(I->getOperand(0), I->getOperand(1), diff --git a/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp b/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp index 010b7b57c3e..0bd6fd2f226 100644 --- a/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp +++ b/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp @@ -3928,8 +3928,8 @@ Instruction *InstCombiner::visitFCmpInst(FCmpInst &I) { Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1); - if (Value *V = - SimplifyFCmpInst(I.getPredicate(), Op0, Op1, DL, TLI, DT, AC, &I)) + if (Value *V = SimplifyFCmpInst(I.getPredicate(), Op0, Op1, + I.getFastMathFlags(), DL, TLI, DT, AC, &I)) return ReplaceInstUsesWith(I, V); // Simplify 'fcmp pred X, X' diff --git a/llvm/test/Transforms/InstSimplify/floating-point-compare.ll b/llvm/test/Transforms/InstSimplify/floating-point-compare.ll index af48d062b4f..8174f583453 100644 --- a/llvm/test/Transforms/InstSimplify/floating-point-compare.ll +++ b/llvm/test/Transforms/InstSimplify/floating-point-compare.ll @@ -58,3 +58,18 @@ define i1 @orderedLessZeroPowi(double,double) { ret i1 %olt } +define i1 @nonans1(double %in1, double %in2) { + %cmp = fcmp nnan uno double %in1, %in2 + ret i1 %cmp + +; CHECK-LABEL: @nonans1 +; CHECK-NEXT: ret i1 false +} + +define i1 @nonans2(double %in1, double %in2) { + %cmp = fcmp nnan ord double %in1, %in2 + ret i1 %cmp + +; CHECK-LABEL: @nonans2 +; CHECK-NEXT: ret i1 true +} |
