Index: llvm/trunk/lib/Transforms/Utils/SimplifyLibCalls.cpp =================================================================== --- llvm/trunk/lib/Transforms/Utils/SimplifyLibCalls.cpp +++ llvm/trunk/lib/Transforms/Utils/SimplifyLibCalls.cpp @@ -993,16 +993,20 @@ Ret = optimizeUnaryDoubleFP(CI, B, true); Value *Op1 = CI->getArgOperand(0), *Op2 = CI->getArgOperand(1); + + // pow(1.0, x) -> 1.0 + if (match(Op1, m_SpecificFP(1.0))) + return Op1; + // pow(2.0, x) -> llvm.exp2(x) + if (match(Op1, m_SpecificFP(2.0))) { + Value *Exp2 = Intrinsic::getDeclaration(CI->getModule(), Intrinsic::exp2, + CI->getType()); + return B.CreateCall(Exp2, Op2, "exp2"); + } + + // There's no llvm.exp10 intrinsic yet, but, maybe, some day there will + // be one. if (ConstantFP *Op1C = dyn_cast(Op1)) { - // pow(1.0, x) -> 1.0 - if (Op1C->isExactlyValue(1.0)) - return Op1C; - // pow(2.0, x) -> exp2(x) - if (Op1C->isExactlyValue(2.0) && - hasUnaryFloatFn(TLI, Op1->getType(), LibFunc::exp2, LibFunc::exp2f, - LibFunc::exp2l)) - return emitUnaryFloatFnCall(Op2, TLI->getName(LibFunc::exp2), B, - Callee->getAttributes()); // pow(10.0, x) -> exp10(x) if (Op1C->isExactlyValue(10.0) && hasUnaryFloatFn(TLI, Op1->getType(), LibFunc::exp10, LibFunc::exp10f, Index: llvm/trunk/test/Transforms/InstCombine/pow-1.ll =================================================================== --- llvm/trunk/test/Transforms/InstCombine/pow-1.ll +++ llvm/trunk/test/Transforms/InstCombine/pow-1.ll @@ -37,7 +37,7 @@ define float @test_simplify3(float %x) { ; CHECK-LABEL: @test_simplify3( %retval = call float @powf(float 2.0, float %x) -; CHECK-NEXT: [[EXP2F:%[a-z0-9]+]] = call float @exp2f(float %x) [[NUW_RO:#[0-9]+]] +; CHECK-NEXT: [[EXP2F:%[a-z0-9]+]] = call float @llvm.exp2.f32(float %x) ret float %retval ; CHECK-NEXT: ret float [[EXP2F]] } @@ -45,7 +45,7 @@ define double @test_simplify4(double %x) { ; CHECK-LABEL: @test_simplify4( %retval = call double @pow(double 2.0, double %x) -; CHECK-NEXT: [[EXP2:%[a-z0-9]+]] = call double @exp2(double %x) [[NUW_RO]] +; CHECK-NEXT: [[EXP2:%[a-z0-9]+]] = call double @llvm.exp2.f64(double %x) ret double %retval ; CHECK-NEXT: ret double [[EXP2]] } @@ -71,7 +71,7 @@ define float @test_simplify7(float %x) { ; CHECK-LABEL: @test_simplify7( %retval = call float @powf(float %x, float 0.5) -; CHECK-NEXT: [[SQRTF:%[a-z0-9]+]] = call float @sqrtf(float %x) [[NUW_RO]] +; CHECK-NEXT: [[SQRTF:%[a-z0-9]+]] = call float @sqrtf(float %x) [[NUW_RO:#[0-9]+]] ; CHECK-NEXT: [[FABSF:%[a-z0-9]+]] = call float @fabsf(float [[SQRTF]]) [[NUW_RO]] ; CHECK-NEXT: [[FCMP:%[a-z0-9]+]] = fcmp oeq float %x, 0xFFF0000000000000 ; CHECK-NEXT: [[SELECT:%[a-z0-9]+]] = select i1 [[FCMP]], float 0x7FF0000000000000, float [[FABSF]]