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| author | Sanjay Patel <spatel@rotateright.com> | 2014-08-14 15:15:28 +0000 |
|---|---|---|
| committer | Sanjay Patel <spatel@rotateright.com> | 2014-08-14 15:15:28 +0000 |
| commit | 35d3133650e7f1907d03c98886286e328cee12e8 (patch) | |
| tree | 644f7f65161ac0311b7f412a22ad67e4c267ce4d /llvm/test/CodeGen/ARM/fnegs.ll | |
| parent | 36d3ee7c32cfeda4c76cb556781ef113c8463dff (diff) | |
| download | bcm5719-llvm-35d3133650e7f1907d03c98886286e328cee12e8.tar.gz bcm5719-llvm-35d3133650e7f1907d03c98886286e328cee12e8.zip | |
optimize vector fneg of bitcasted integer value
This patch allows a vector fneg of a bitcasted integer value to be optimized in the same way that we already optimize a scalar fneg. If the integer variable is a constant, we can precompute the result and not require any logic ops.
This patch is very similar to a fabs patch committed at r214892.
Differential Revision: http://reviews.llvm.org/D4852
llvm-svn: 215646
Diffstat (limited to 'llvm/test/CodeGen/ARM/fnegs.ll')
| -rw-r--r-- | llvm/test/CodeGen/ARM/fnegs.ll | 46 |
1 files changed, 46 insertions, 0 deletions
diff --git a/llvm/test/CodeGen/ARM/fnegs.ll b/llvm/test/CodeGen/ARM/fnegs.ll index 99146b923a4..65fe9e36fa1 100644 --- a/llvm/test/CodeGen/ARM/fnegs.ll +++ b/llvm/test/CodeGen/ARM/fnegs.ll @@ -73,3 +73,49 @@ entry: ; CORTEXA9-LABEL: test2: ; CORTEXA9: vneg.f32 s{{.*}}, s{{.*}} +; If we're bitcasting an integer to an FP vector, we should avoid the FP/vector unit entirely. +; Make sure that we're flipping the sign bit and only the sign bit of each float (PR20354). +; So instead of something like this: +; vmov d16, r0, r1 +; vneg.f32 d16, d16 +; vmov r0, r1, d16 +; +; We should generate: +; eor r0, r0, #-214783648 +; eor r1, r1, #-214783648 + +define <2 x float> @fneg_bitcast(i64 %i) { + %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 +} +; VFP2-LABEL: fneg_bitcast: +; VFP2-DAG: eor r0, r0, #-2147483648 +; VFP2-DAG: eor r1, r1, #-2147483648 +; VFP2-NOT: vneg.f32 + +; NFP1-LABEL: fneg_bitcast: +; NFP1-DAG: eor r0, r0, #-2147483648 +; NFP1-DAG: eor r1, r1, #-2147483648 +; NFP1-NOT: vneg.f32 + +; NFP0-LABEL: fneg_bitcast: +; NFP0-DAG: eor r0, r0, #-2147483648 +; NFP0-DAG: eor r1, r1, #-2147483648 +; NFP0-NOT: vneg.f32 + +; CORTEXA8-LABEL: fneg_bitcast: +; CORTEXA8-DAG: eor r0, r0, #-2147483648 +; CORTEXA8-DAG: eor r1, r1, #-2147483648 +; CORTEXA8-NOT: vneg.f32 + +; CORTEXA8U-LABEL: fneg_bitcast: +; CORTEXA8U-DAG: eor r0, r0, #-2147483648 +; CORTEXA8U-DAG: eor r1, r1, #-2147483648 +; CORTEXA8U-NOT: vneg.f32 + +; CORTEXA9-LABEL: fneg_bitcast: +; CORTEXA9-DAG: eor r0, r0, #-2147483648 +; CORTEXA9-DAG: eor r1, r1, #-2147483648 +; CORTEXA9-NOT: vneg.f32 + |
