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Diffstat (limited to 'llvm/test/CodeGen/X86/combine-fneg.ll')
-rw-r--r-- | llvm/test/CodeGen/X86/combine-fneg.ll | 208 |
1 files changed, 208 insertions, 0 deletions
diff --git a/llvm/test/CodeGen/X86/combine-fneg.ll b/llvm/test/CodeGen/X86/combine-fneg.ll new file mode 100644 index 0000000..df7dcc0 --- /dev/null +++ b/llvm/test/CodeGen/X86/combine-fneg.ll @@ -0,0 +1,208 @@ +; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py +; RUN: llc < %s -mtriple=i686-unknown-unknown -mattr=+sse | FileCheck %s --check-prefix=X32-SSE --check-prefix=X32-SSE1 +; RUN: llc < %s -mtriple=i686-unknown-unknown -mattr=+sse2 | FileCheck %s --check-prefix=X32-SSE --check-prefix=X32-SSE2 +; RUN: llc < %s -mtriple=x86_64-unknown-unknown -mattr=-sse2 | FileCheck %s --check-prefix=X64-SSE --check-prefix=X64-SSE1 +; RUN: llc < %s -mtriple=x86_64-unknown-unknown -mattr=+sse2 | FileCheck %s --check-prefix=X64-SSE --check-prefix=X64-SSE2 + +; 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) nounwind { +; X32-SSE-LABEL: t1: +; X32-SSE: # %bb.0: +; X32-SSE-NEXT: xorps {{\.?LCPI[0-9]+_[0-9]+}}, %xmm0 +; X32-SSE-NEXT: retl +; +; X64-SSE-LABEL: t1: +; X64-SSE: # %bb.0: +; X64-SSE-NEXT: xorps {{\.?LCPI[0-9]+_[0-9]+}}(%rip), %xmm0 +; X64-SSE-NEXT: retq + %tmp = fsub <4 x float> <float -0.0, float -0.0, float -0.0, float -0.0>, %Q + ret <4 x float> %tmp +} + +; Possibly misplaced test, but since we're checking undef scenarios... + +define float @scalar_fsub_neg0_undef(float %x) nounwind { +; X32-SSE-LABEL: scalar_fsub_neg0_undef: +; X32-SSE: # %bb.0: +; X32-SSE-NEXT: fldz +; X32-SSE-NEXT: retl +; +; X64-SSE-LABEL: scalar_fsub_neg0_undef: +; X64-SSE: # %bb.0: +; X64-SSE-NEXT: retq + %r = fsub float -0.0, undef + ret float %r +} + +define float @scalar_fneg_undef(float %x) nounwind { +; X32-SSE-LABEL: scalar_fneg_undef: +; X32-SSE: # %bb.0: +; X32-SSE-NEXT: fldz +; X32-SSE-NEXT: retl +; +; X64-SSE-LABEL: scalar_fneg_undef: +; X64-SSE: # %bb.0: +; X64-SSE-NEXT: retq + %r = fneg float undef + ret float %r +} + +define <4 x float> @fsub_neg0_undef(<4 x float> %Q) nounwind { +; X32-SSE-LABEL: fsub_neg0_undef: +; X32-SSE: # %bb.0: +; X32-SSE-NEXT: retl +; +; X64-SSE-LABEL: fsub_neg0_undef: +; X64-SSE: # %bb.0: +; X64-SSE-NEXT: retq + %r = fsub <4 x float> <float -0.0, float -0.0, float -0.0, float -0.0>, undef + ret <4 x float> %r +} + +define <4 x float> @fneg_undef(<4 x float> %Q) nounwind { +; X32-SSE-LABEL: fneg_undef: +; X32-SSE: # %bb.0: +; X32-SSE-NEXT: retl +; +; X64-SSE-LABEL: fneg_undef: +; X64-SSE: # %bb.0: +; X64-SSE-NEXT: retq + %r = fneg <4 x float> undef + ret <4 x float> %r +} + +define <4 x float> @fsub_neg0_undef_elts_undef(<4 x float> %x) { +; X32-SSE-LABEL: fsub_neg0_undef_elts_undef: +; X32-SSE: # %bb.0: +; X32-SSE-NEXT: retl +; +; X64-SSE-LABEL: fsub_neg0_undef_elts_undef: +; X64-SSE: # %bb.0: +; X64-SSE-NEXT: retq + %r = fsub <4 x float> <float -0.0, float undef, float undef, float -0.0>, undef + ret <4 x float> %r +} + +; 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) nounwind { +; X32-SSE-LABEL: t2: +; X32-SSE: # %bb.0: +; X32-SSE-NEXT: xorps %xmm1, %xmm1 +; X32-SSE-NEXT: subps %xmm0, %xmm1 +; X32-SSE-NEXT: movaps %xmm1, %xmm0 +; X32-SSE-NEXT: retl +; +; X64-SSE-LABEL: t2: +; X64-SSE: # %bb.0: +; X64-SSE-NEXT: xorps %xmm1, %xmm1 +; X64-SSE-NEXT: subps %xmm0, %xmm1 +; X64-SSE-NEXT: movaps %xmm1, %xmm0 +; X64-SSE-NEXT: retq + %tmp = fsub <4 x float> zeroinitializer, %Q + ret <4 x float> %tmp +} + +; If we're bitcasting an integer to an FP vector, we should avoid the FPU/vector unit entirely. +; Make sure that we're flipping the sign bit and only the sign bit of each float. +; So instead of something like this: +; movd %rdi, %xmm0 +; xorps .LCPI2_0(%rip), %xmm0 +; +; We should generate: +; movabsq (put sign bit mask in integer register)) +; xorq (flip sign bits) +; movd (move to xmm return register) + +define <2 x float> @fneg_bitcast(i64 %i) nounwind { +; X32-SSE1-LABEL: fneg_bitcast: +; X32-SSE1: # %bb.0: +; X32-SSE1-NEXT: pushl %ebp +; X32-SSE1-NEXT: movl %esp, %ebp +; X32-SSE1-NEXT: andl $-16, %esp +; X32-SSE1-NEXT: subl $16, %esp +; X32-SSE1-NEXT: movl $-2147483648, %eax # imm = 0x80000000 +; X32-SSE1-NEXT: movl 12(%ebp), %ecx +; X32-SSE1-NEXT: xorl %eax, %ecx +; X32-SSE1-NEXT: movl %ecx, {{[0-9]+}}(%esp) +; X32-SSE1-NEXT: xorl 8(%ebp), %eax +; X32-SSE1-NEXT: movl %eax, (%esp) +; X32-SSE1-NEXT: movaps (%esp), %xmm0 +; X32-SSE1-NEXT: movl %ebp, %esp +; X32-SSE1-NEXT: popl %ebp +; X32-SSE1-NEXT: retl +; +; X32-SSE2-LABEL: fneg_bitcast: +; X32-SSE2: # %bb.0: +; X32-SSE2-NEXT: movl $-2147483648, %eax # imm = 0x80000000 +; X32-SSE2-NEXT: movl {{[0-9]+}}(%esp), %ecx +; X32-SSE2-NEXT: xorl %eax, %ecx +; X32-SSE2-NEXT: movd %ecx, %xmm1 +; X32-SSE2-NEXT: xorl {{[0-9]+}}(%esp), %eax +; X32-SSE2-NEXT: movd %eax, %xmm0 +; X32-SSE2-NEXT: punpckldq {{.*#+}} xmm0 = xmm0[0],xmm1[0],xmm0[1],xmm1[1] +; X32-SSE2-NEXT: retl +; +; X64-SSE1-LABEL: fneg_bitcast: +; X64-SSE1: # %bb.0: +; X64-SSE1-NEXT: movabsq $-9223372034707292160, %rax # imm = 0x8000000080000000 +; X64-SSE1-NEXT: xorq %rdi, %rax +; X64-SSE1-NEXT: movq %rax, -{{[0-9]+}}(%rsp) +; X64-SSE1-NEXT: movaps -{{[0-9]+}}(%rsp), %xmm0 +; X64-SSE1-NEXT: retq +; +; X64-SSE2-LABEL: fneg_bitcast: +; X64-SSE2: # %bb.0: +; X64-SSE2-NEXT: movabsq $-9223372034707292160, %rax # imm = 0x8000000080000000 +; X64-SSE2-NEXT: xorq %rdi, %rax +; X64-SSE2-NEXT: movq %rax, %xmm0 +; X64-SSE2-NEXT: retq + %bitcast = bitcast i64 %i to <2 x float> + %fneg = fsub <2 x float> <float -0.0, float -0.0>, %bitcast + ret <2 x float> %fneg +} + +define <4 x float> @fneg_undef_elts_v4f32(<4 x float> %x) { +; X32-SSE-LABEL: fneg_undef_elts_v4f32: +; X32-SSE: # %bb.0: +; X32-SSE-NEXT: xorps {{\.?LCPI[0-9]+_[0-9]+}}, %xmm0 +; X32-SSE-NEXT: retl +; +; X64-SSE-LABEL: fneg_undef_elts_v4f32: +; X64-SSE: # %bb.0: +; X64-SSE-NEXT: xorps {{\.?LCPI[0-9]+_[0-9]+}}(%rip), %xmm0 +; X64-SSE-NEXT: retq + %r = fsub <4 x float> <float -0.0, float undef, float undef, float -0.0>, %x + ret <4 x float> %r +} + +; This isn't fneg, but similarly check that (X - 0.0) is simplified. + +define <4 x float> @fsub0_undef_elts_v4f32(<4 x float> %x) { +; X32-SSE-LABEL: fsub0_undef_elts_v4f32: +; X32-SSE: # %bb.0: +; X32-SSE-NEXT: retl +; +; X64-SSE-LABEL: fsub0_undef_elts_v4f32: +; X64-SSE: # %bb.0: +; X64-SSE-NEXT: retq + %r = fsub <4 x float> %x, <float 0.0, float undef, float 0.0, float undef> + ret <4 x float> %r +} + +define <4 x float> @fneg(<4 x float> %Q) nounwind { +; X32-SSE-LABEL: fneg: +; X32-SSE: # %bb.0: +; X32-SSE-NEXT: xorps {{\.?LCPI[0-9]+_[0-9]+}}, %xmm0 +; X32-SSE-NEXT: retl +; +; X64-SSE-LABEL: fneg: +; X64-SSE: # %bb.0: +; X64-SSE-NEXT: xorps {{\.?LCPI[0-9]+_[0-9]+}}(%rip), %xmm0 +; X64-SSE-NEXT: retq + %tmp = fneg <4 x float> %Q + ret <4 x float> %tmp +} + + |