diff options
Diffstat (limited to 'llvm/lib')
| -rw-r--r-- | llvm/lib/Target/X86/X86InstrSSE.td | 23 |
1 files changed, 17 insertions, 6 deletions
diff --git a/llvm/lib/Target/X86/X86InstrSSE.td b/llvm/lib/Target/X86/X86InstrSSE.td index c2626808774..65b155c0a9d 100644 --- a/llvm/lib/Target/X86/X86InstrSSE.td +++ b/llvm/lib/Target/X86/X86InstrSSE.td @@ -7168,6 +7168,10 @@ let Predicates = [HasAVX2] in { } // Patterns +// FIXME: Prefer a movss or movsd over a blendps when optimizing for size or +// on targets where they have equal performance. These were changed to use +// blends because blends have better throughput on SandyBridge and Haswell, but +// movs[s/d] are 1-2 byte shorter instructions. let Predicates = [UseAVX] in { let AddedComplexity = 15 in { // Move scalar to XMM zero-extended, zeroing a VR128 then do a @@ -7184,8 +7188,10 @@ let Predicates = [UseAVX] in { // Move low f32 and clear high bits. def : Pat<(v8f32 (X86vzmovl (v8f32 VR256:$src))), (VBLENDPSYrri (v8f32 (AVX_SET0)), VR256:$src, (i8 1))>; - def : Pat<(v8i32 (X86vzmovl (v8i32 VR256:$src))), - (VBLENDPSYrri (v8i32 (AVX_SET0)), VR256:$src, (i8 1))>; + + // Move low f64 and clear high bits. + def : Pat<(v4f64 (X86vzmovl (v4f64 VR256:$src))), + (VBLENDPDYrri (v4f64 (AVX_SET0)), VR256:$src, (i8 1))>; } def : Pat<(v8f32 (X86vzmovl (insert_subvector undef, @@ -7199,14 +7205,19 @@ let Predicates = [UseAVX] in { (v2f64 (VMOVSDrr (v2f64 (V_SET0)), FR64:$src)), sub_xmm)>; - // Move low f64 and clear high bits. - def : Pat<(v4f64 (X86vzmovl (v4f64 VR256:$src))), - (VBLENDPDYrri (v4f64 (AVX_SET0)), VR256:$src, (i8 1))>; - + // These will incur an FP/int domain crossing penalty, but it may be the only + // way without AVX2. Do not add any complexity because we may be able to match + // more optimal patterns defined earlier in this file. + def : Pat<(v8i32 (X86vzmovl (v8i32 VR256:$src))), + (VBLENDPSYrri (v8i32 (AVX_SET0)), VR256:$src, (i8 1))>; def : Pat<(v4i64 (X86vzmovl (v4i64 VR256:$src))), (VBLENDPDYrri (v4i64 (AVX_SET0)), VR256:$src, (i8 1))>; } +// FIXME: Prefer a movss or movsd over a blendps when optimizing for size or +// on targets where they have equal performance. These were changed to use +// blends because blends have better throughput on SandyBridge and Haswell, but +// movs[s/d] are 1-2 byte shorter instructions. let Predicates = [UseSSE41] in { // With SSE41 we can use blends for these patterns. def : Pat<(v4f32 (X86vzmovl (v4f32 VR128:$src))), |
