[llvm] [X86] getFauxShuffleMask - add support for vXi64/vXf64 concat_vectors decoding (PR #127630)

[Phoebe Wang via llvm-commits]

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@@ -1215,10 +1215,10 @@ define void @store_i8_stride7_vf8(ptr %in.vecptr0, ptr %in.vecptr1, ptr %in.vecp
 ; AVX512BW-NEXT:    vpshufb {{.*#+}} zmm0 = zero,zero,zero,zero,zero,zero,zmm0[0],zero,zero,zero,zero,zero,zero,zmm0[1],zero,zero,zero,zero,zmm0[18,26],zero,zero,zero,zero,zero,zmm0[19,27],zero,zero,zero,zero,zero,zero,zero,zmm0[36],zero,zero,zero,zero,zero,zero,zmm0[37],zero,zero,zero,zero,zero,zero,zero,zero,zero,zero,zero,zmm0[55,63],zero,zero,zero,zero,zero,zero,zero,zero,zero
 ; AVX512BW-NEXT:    vporq %zmm1, %zmm0, %zmm0
 ; AVX512BW-NEXT:    vinserti64x4 $1, %ymm2, %zmm2, %zmm1
-; AVX512BW-NEXT:    vpshufb {{.*#+}} zmm2 = zmm1[0,8],zero,zero,zero,zero,zero,zmm1[1,9],zero,zero,zero,zero,zero,zmm1[2,10,18,26],zero,zero,zero,zero,zero,zmm1[19,27],zero,zero,zero,zero,zero,zmm1[20,28],zero,zero,zero,zmm1[37,45],zero,zero,zero,zero,zero,zmm1[38,46],zero,zero,zero,zero,zero,zero,zero,zmm1[55,63],zero,zero,zero,zero,zero,zero,zero,zero,zero,zero,zero
-; AVX512BW-NEXT:    vpermq {{.*#+}} zmm1 = zmm1[2,3,0,1,6,7,4,5]
-; AVX512BW-NEXT:    vpshufb {{.*#+}} zmm1 = zero,zero,zmm1[0,8],zero,zero,zero,zero,zero,zmm1[1,9],zero,zero,zero,zero,zero,zero,zero,zero,zero,zero,zmm1[19,27],zero,zero,zero,zero,zero,zmm1[20,28],zero,zero,zero,zero,zero,zero,zero,zmm1[37,45],zero,zero,zero,zero,zero,zmm1[38,46],zero,zero,zero,zmm1[55,63],zero,zero,zero,zero,zero,zero,zero,zero,zero,zero,zero,zero,zero
-; AVX512BW-NEXT:    vporq %zmm2, %zmm1, %zmm1
+; AVX512BW-NEXT:    vpshufb {{.*#+}} zmm1 = zmm1[0,8],zero,zero,zero,zero,zero,zmm1[1,9],zero,zero,zero,zero,zero,zmm1[2,10,18,26],zero,zero,zero,zero,zero,zmm1[19,27],zero,zero,zero,zero,zero,zmm1[20,28],zero,zero,zero,zmm1[37,45],zero,zero,zero,zero,zero,zmm1[38,46],zero,zero,zero,zero,zero,zero,zero,zmm1[55,63],zero,zero,zero,zero,zero,zero,zero,zero,zero,zero,zero
+; AVX512BW-NEXT:    vshufi64x2 {{.*#+}} zmm2 = zmm2[2,3,0,1,2,3,0,1]
+; AVX512BW-NEXT:    vpshufb {{.*#+}} zmm2 = zero,zero,zmm2[0,8],zero,zero,zero,zero,zero,zmm2[1,9],zero,zero,zero,zero,zero,zero,zero,zero,zero,zero,zmm2[19,27],zero,zero,zero,zero,zero,zmm2[20,28],zero,zero,zero,zero,zero,zero,zero,zmm2[37,45],zero,zero,zero,zero,zero,zmm2[38,46],zero,zero,zero,zmm2[55,63],zero,zero,zero,zero,zero,zero,zero,zero,zero,zero,zero,zero,zero
+; AVX512BW-NEXT:    vporq %zmm1, %zmm2, %zmm1
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phoebewang wrote:

I see, thanks! I checked `vpermq` almost has the same uop/tp with `vshufi64x2`, except it can be fused to 1 uop sometimes. I think the difference is minor and can be ignored here.

https://github.com/llvm/llvm-project/pull/127630