diff options
| -rw-r--r-- | llvm/lib/Support/APFloat.cpp | 4 | ||||
| -rw-r--r-- | llvm/test/Transforms/InstSimplify/fold-builtin-fma.ll | 119 |
2 files changed, 121 insertions, 2 deletions
diff --git a/llvm/lib/Support/APFloat.cpp b/llvm/lib/Support/APFloat.cpp index 57fbe897fc8..f63d7748973 100644 --- a/llvm/lib/Support/APFloat.cpp +++ b/llvm/lib/Support/APFloat.cpp @@ -954,7 +954,7 @@ APFloat::multiplySignificand(const APFloat &rhs, const APFloat *addend) // exponent accordingly. exponent += 1; - if (addend) { + if (addend && addend->isNonZero()) { // The intermediate result of the multiplication has "2 * precision" // signicant bit; adjust the addend to be consistent with mul result. // @@ -1800,7 +1800,7 @@ APFloat::fusedMultiplyAdd(const APFloat &multiplicand, extended-precision calculation. */ if (isFiniteNonZero() && multiplicand.isFiniteNonZero() && - addend.isFiniteNonZero()) { + addend.isFinite()) { lostFraction lost_fraction; lost_fraction = multiplySignificand(multiplicand, &addend); diff --git a/llvm/test/Transforms/InstSimplify/fold-builtin-fma.ll b/llvm/test/Transforms/InstSimplify/fold-builtin-fma.ll new file mode 100644 index 00000000000..6331b8c2dd4 --- /dev/null +++ b/llvm/test/Transforms/InstSimplify/fold-builtin-fma.ll @@ -0,0 +1,119 @@ +; RUN: opt -instsimplify -S < %s | FileCheck %s + +; Fixes PR20832 +; Make sure that we correctly fold a fused multiply-add where operands +; are all finite constants and addend is zero. + +declare double @llvm.fma.f64(double, double, double) + + +define double @PR20832() { + %1 = call double @llvm.fma.f64(double 7.0, double 8.0, double 0.0) + ret double %1 +} +; CHECK-LABEL: @PR20832( +; CHECK: ret double 5.600000e+01 + +; Test builtin fma with all finite non-zero constants. +define double @test_all_finite() { + %1 = call double @llvm.fma.f64(double 7.0, double 8.0, double 5.0) + ret double %1 +} +; CHECK-LABEL: @test_all_finite( +; CHECK: ret double 6.100000e+01 + +; Test builtin fma with a +/-NaN addend. +define double @test_NaN_addend() { + %1 = call double @llvm.fma.f64(double 7.0, double 8.0, double 0x7FF8000000000000) + ret double %1 +} +; CHECK-LABEL: @test_NaN_addend( +; CHECK: ret double 0x7FF8000000000000 + +define double @test_NaN_addend_2() { + %1 = call double @llvm.fma.f64(double 7.0, double 8.0, double 0xFFF8000000000000) + ret double %1 +} +; CHECK-LABEL: @test_NaN_addend_2( +; CHECK: ret double 0xFFF8000000000000 + +; Test builtin fma with a +/-Inf addend. +define double @test_Inf_addend() { + %1 = call double @llvm.fma.f64(double 7.0, double 8.0, double 0x7FF0000000000000) + ret double %1 +} +; CHECK-LABEL: @test_Inf_addend( +; CHECK: ret double 0x7FF0000000000000 + +define double @test_Inf_addend_2() { + %1 = call double @llvm.fma.f64(double 7.0, double 8.0, double 0xFFF0000000000000) + ret double %1 +} +; CHECK-LABEL: @test_Inf_addend_2( +; CHECK: ret double 0xFFF0000000000000 + +; Test builtin fma with one of the operands to the multiply being +/-NaN. +define double @test_NaN_1() { + %1 = call double @llvm.fma.f64(double 0x7FF8000000000000, double 8.0, double 0.0) + ret double %1 +} +; CHECK-LABEL: @test_NaN_1( +; CHECK: ret double 0x7FF8000000000000 + + +define double @test_NaN_2() { + %1 = call double @llvm.fma.f64(double 7.0, double 0x7FF8000000000000, double 0.0) + ret double %1 +} +; CHECK-LABEL: @test_NaN_2( +; CHECK: ret double 0x7FF8000000000000 + + +define double @test_NaN_3() { + %1 = call double @llvm.fma.f64(double 0xFFF8000000000000, double 8.0, double 0.0) + ret double %1 +} +; CHECK-LABEL: @test_NaN_3( +; CHECK: ret double 0x7FF8000000000000 + + +define double @test_NaN_4() { + %1 = call double @llvm.fma.f64(double 7.0, double 0xFFF8000000000000, double 0.0) + ret double %1 +} +; CHECK-LABEL: @test_NaN_4( +; CHECK: ret double 0x7FF8000000000000 + + +; Test builtin fma with one of the operands to the multiply being +/-Inf. +define double @test_Inf_1() { + %1 = call double @llvm.fma.f64(double 0x7FF0000000000000, double 8.0, double 0.0) + ret double %1 +} +; CHECK-LABEL: @test_Inf_1( +; CHECK: ret double 0x7FF0000000000000 + + +define double @test_Inf_2() { + %1 = call double @llvm.fma.f64(double 7.0, double 0x7FF0000000000000, double 0.0) + ret double %1 +} +; CHECK-LABEL: @test_Inf_2( +; CHECK: ret double 0x7FF0000000000000 + + +define double @test_Inf_3() { + %1 = call double @llvm.fma.f64(double 0xFFF0000000000000, double 8.0, double 0.0) + ret double %1 +} +; CHECK-LABEL: @test_Inf_3( +; CHECK: ret double 0xFFF0000000000000 + + +define double @test_Inf_4() { + %1 = call double @llvm.fma.f64(double 7.0, double 0xFFF0000000000000, double 0.0) + ret double %1 +} +; CHECK-LABEL: @test_Inf_4( +; CHECK: ret double 0xFFF0000000000000 + |
