diff options
| -rw-r--r-- | llvm/test/CodeGen/X86/vec_fneg.ll | 22 |
1 files changed, 17 insertions, 5 deletions
diff --git a/llvm/test/CodeGen/X86/vec_fneg.ll b/llvm/test/CodeGen/X86/vec_fneg.ll index d49c70e5639..00383be02c9 100644 --- a/llvm/test/CodeGen/X86/vec_fneg.ll +++ b/llvm/test/CodeGen/X86/vec_fneg.ll @@ -1,11 +1,23 @@ -; RUN: llc < %s -march=x86 -mattr=+sse2 +; RUN: llc < %s -mtriple=x86_64-unknown-unknown -mcpu=corei7 | FileCheck %s +; FNEG is defined as subtraction from -0.0. + +; This test verifies that we use an xor with a constant to flip the sign bits; no subtraction needed. define <4 x float> @t1(<4 x float> %Q) { - %tmp15 = fsub <4 x float> < float -0.000000e+00, float -0.000000e+00, float -0.000000e+00, float -0.000000e+00 >, %Q - ret <4 x float> %tmp15 +; CHECK-LABEL: t1: +; CHECK: xorps {{.*}}LCPI0_0{{.*}}, %xmm0 +; CHECK-NEXT: retq + %tmp = fsub <4 x float> < float -0.000000e+00, float -0.000000e+00, float -0.000000e+00, float -0.000000e+00 >, %Q + ret <4 x float> %tmp } +; This test verifies that we generate an FP subtraction because "0.0 - x" is not an fneg. define <4 x float> @t2(<4 x float> %Q) { - %tmp15 = fsub <4 x float> zeroinitializer, %Q - ret <4 x float> %tmp15 +; CHECK-LABEL: t2: +; CHECK: xorps %[[X:xmm[0-9]+]], %[[X]] +; CHECK-NEXT: subps %xmm0, %[[X]] +; CHECK-NEXT: movaps %[[X]], %xmm0 +; CHECK-NEXT: retq + %tmp = fsub <4 x float> zeroinitializer, %Q + ret <4 x float> %tmp } |
