[llvm] [X86] X86FixupVectorConstants - shrink vector load to movsd/movsd/movd/movq 'zero upper' instructions (PR #79000)

[Phoebe Wang via llvm-commits]

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@@ -563,15 +563,15 @@ define <16 x i1> @interleaved_load_vf16_i8_stride4(ptr %ptr) nounwind {
 define <32 x i1> @interleaved_load_vf32_i8_stride4(ptr %ptr) nounwind {
 ; AVX1-LABEL: interleaved_load_vf32_i8_stride4:
 ; AVX1:       # %bb.0:
-; AVX1-NEXT:    vbroadcastss {{.*#+}} xmm6 = [0,4,8,12,0,4,8,12,0,4,8,12,0,4,8,12]
+; AVX1-NEXT:    vmovq {{.*#+}} xmm6 = [0,0,0,0,0,4,8,12,0,0,0,0,0,0,0,0]
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phoebewang wrote:

I see what's your mean by smaller broadcast constant, but I don't get the point why it's better here.

https://github.com/llvm/llvm-project/pull/79000