diff --git a/llvm/include/llvm/Analysis/InstructionSimplify.h b/llvm/include/llvm/Analysis/InstructionSimplify.h index 6db400c563d6..ce7818184e9a 100644 --- a/llvm/include/llvm/Analysis/InstructionSimplify.h +++ b/llvm/include/llvm/Analysis/InstructionSimplify.h @@ -25,6 +25,7 @@ namespace llvm { class DominatorTree; class Instruction; class DataLayout; + struct FastMathFlags; class TargetLibraryInfo; class Type; class Value; @@ -43,6 +44,14 @@ namespace llvm { const TargetLibraryInfo *TLI = 0, const DominatorTree *DT = 0); + /// Given operands for an FMul, see if we can fold the result. If not, this + /// returns null. + Value *SimplifyFMulInst(Value *LHS, Value *RHS, + FastMathFlags FMF, + const DataLayout *TD = 0, + const TargetLibraryInfo *TLI = 0, + const DominatorTree *DT = 0); + /// SimplifyMulInst - Given operands for a Mul, see if we can /// fold the result. If not, this returns null. Value *SimplifyMulInst(Value *LHS, Value *RHS, const DataLayout *TD = 0, diff --git a/llvm/lib/Analysis/InstructionSimplify.cpp b/llvm/lib/Analysis/InstructionSimplify.cpp index a76e5ad1b8f8..e3fe9240d0fd 100644 --- a/llvm/lib/Analysis/InstructionSimplify.cpp +++ b/llvm/lib/Analysis/InstructionSimplify.cpp @@ -886,6 +886,33 @@ Value *llvm::SimplifySubInst(Value *Op0, Value *Op1, bool isNSW, bool isNUW, RecursionLimit); } +/// Given the operands for an FMul, see if we can fold the result +static Value *SimplifyFMulInst(Value *Op0, Value *Op1, + FastMathFlags FMF, + const Query &Q, + unsigned MaxRecurse) { + if (Constant *CLHS = dyn_cast(Op0)) { + if (Constant *CRHS = dyn_cast(Op1)) { + Constant *Ops[] = { CLHS, CRHS }; + return ConstantFoldInstOperands(Instruction::FMul, CLHS->getType(), + Ops, Q.TD, Q.TLI); + } + } + + // Check for some fast-math optimizations + if (FMF.NoNaNs) { + if (FMF.NoSignedZeros) { + // fmul N S 0, x ==> 0 + if (match(Op0, m_Zero())) + return Op0; + if (match(Op1, m_Zero())) + return Op1; + } + } + + return 0; +} + /// SimplifyMulInst - Given operands for a Mul, see if we can /// fold the result. If not, this returns null. static Value *SimplifyMulInst(Value *Op0, Value *Op1, const Query &Q, @@ -951,6 +978,14 @@ static Value *SimplifyMulInst(Value *Op0, Value *Op1, const Query &Q, return 0; } +Value *llvm::SimplifyFMulInst(Value *Op0, Value *Op1, + FastMathFlags FMF, + const DataLayout *TD, + const TargetLibraryInfo *TLI, + const DominatorTree *DT) { + return ::SimplifyFMulInst(Op0, Op1, FMF, Query (TD, TLI, DT), RecursionLimit); +} + Value *llvm::SimplifyMulInst(Value *Op0, Value *Op1, const DataLayout *TD, const TargetLibraryInfo *TLI, const DominatorTree *DT) { @@ -2799,6 +2834,10 @@ Value *llvm::SimplifyInstruction(Instruction *I, const DataLayout *TD, cast(I)->hasNoUnsignedWrap(), TD, TLI, DT); break; + case Instruction::FMul: + Result = SimplifyFMulInst(I->getOperand(0), I->getOperand(1), + I->getFastMathFlags(), TD, TLI, DT); + break; case Instruction::Mul: Result = SimplifyMulInst(I->getOperand(0), I->getOperand(1), TD, TLI, DT); break;