diff --git a/llvm/lib/Transforms/Utils/SimplifyLibCalls.cpp b/llvm/lib/Transforms/Utils/SimplifyLibCalls.cpp --- a/llvm/lib/Transforms/Utils/SimplifyLibCalls.cpp +++ b/llvm/lib/Transforms/Utils/SimplifyLibCalls.cpp @@ -1562,8 +1562,8 @@ if (match(Expo, m_SpecificFP(-1.0))) return B.CreateFDiv(ConstantFP::get(Ty, 1.0), Base, "reciprocal"); - // pow(x, 0.0) -> 1.0 - if (match(Expo, m_SpecificFP(0.0))) + // pow(x, +/- 0.0) -> 1.0 + if (match(Expo, m_AnyZeroFP())) return ConstantFP::get(Ty, 1.0); // pow(x, 1.0) -> x diff --git a/llvm/test/Transforms/InstCombine/pow-0.ll b/llvm/test/Transforms/InstCombine/pow-0.ll new file mode 100644 --- /dev/null +++ b/llvm/test/Transforms/InstCombine/pow-0.ll @@ -0,0 +1,60 @@ +; RUN: opt < %s -instcombine -S | FileCheck %s + +; CHECK-LABEL: @zero( +; CHECK-NEXT: ret double 1.000000e+00 +define double @zero(double %value) { + %res = call double @llvm.pow.f64(double %value, double 0.000000e+00) + ret double %res +} + +; CHECK-LABEL: @minus_zero( +; CHECK-NEXT: ret double 1.000000e+00 +define double @minus_zero(double %value) { + %res = call double @llvm.pow.f64(double %value, double -0.000000e+00) + ret double %res +} + +; CHECK-LABEL: @fast_zero( +; CHECK-NEXT: ret double 1.000000e+00 +define double @fast_zero(double %value) { + %res = call fast double @llvm.pow.f64(double %value, double 0.000000e+00) + ret double %res +} + +; CHECK-LABEL: @fast_minus_zero( +; CHECK-NEXT: ret double 1.000000e+00 +define double @fast_minus_zero(double %value) { + %res = call fast double @llvm.pow.f64(double %value, double -0.000000e+00) + ret double %res +} + +; CHECK-LABEL: @vec_zero( +; CHECK-NEXT: ret <2 x double> +define <2 x double> @vec_zero(<2 x double> %value) { + %res = call <2 x double> @llvm.pow.v2f64(<2 x double> %value, <2 x double> ) + ret <2 x double> %res +} + +; CHECK-LABEL: @vec_minus_zero( +; CHECK-NEXT: ret <2 x double> +define <2 x double> @vec_minus_zero(<2 x double> %value) { + %res = call <2 x double> @llvm.pow.v2f64(<2 x double> %value, <2 x double> ) + ret <2 x double> %res +} + +; CHECK-LABEL: @vec_fast_zero( +; CHECK-NEXT: ret <2 x double> +define <2 x double> @vec_fast_zero(<2 x double> %value) { + %res = call fast <2 x double> @llvm.pow.v2f64(<2 x double> %value, <2 x double> ) + ret <2 x double> %res +} + +; CHECK-LABEL: @vec_fast_minus_zero( +; CHECK-NEXT: ret <2 x double> +define <2 x double> @vec_fast_minus_zero(<2 x double> %value) { + %res = call fast <2 x double> @llvm.pow.v2f64(<2 x double> %value, <2 x double> ) + ret <2 x double> %res +} + +declare double @llvm.pow.f64(double, double) +declare <2 x double> @llvm.pow.v2f64(<2 x double>, <2 x double>)