[X86] Add shuffle tests from Issue #86076

SLP should be doing a better job, but both shuffles lower to poorer codegen than necessary

Author: RKSimon

llvm/test/CodeGen/X86/vector-shuffle-512-v16.ll

@@ -177,6 +177,36 @@ define <16 x float> @shuffle_v16f32_02_03_16_17_06_07_20_21_10_11_24_25_14_15_28
   ret <16 x float> %shuffle
 }
 
+; PR86076
+define <16 x float> @shuffle_f32_v16f32_00_08_01_09_02_10_03_11_04_12_05_13_06_14_07_15(float %a0, float %a1) {
+; ALL-LABEL: shuffle_f32_v16f32_00_08_01_09_02_10_03_11_04_12_05_13_06_14_07_15:
+; ALL:       # %bb.0:
+; ALL-NEXT:    vbroadcastss %xmm0, %ymm0
+; ALL-NEXT:    vbroadcastss %xmm1, %ymm1
+; ALL-NEXT:    vunpcklps {{.*#+}} ymm0 = ymm0[0],ymm1[0],ymm0[1],ymm1[1],ymm0[4],ymm1[4],ymm0[5],ymm1[5]
+; ALL-NEXT:    vinsertf64x4 $1, %ymm0, %zmm0, %zmm0
+; ALL-NEXT:    retq
+  %v0 = insertelement <8 x float> poison, float %a0, i64 0
+  %v1 = insertelement <8 x float> poison, float %a1, i64 0
+  %b0 = shufflevector <8 x float> %v0, <8 x float> poison, <8 x i32> zeroinitializer
+  %b1 = shufflevector <8 x float> %v1, <8 x float> poison, <8 x i32> zeroinitializer
+  %r = shufflevector <8 x float> %b0, <8 x float> %b1, <16 x i32> <i32 0, i32 8, i32 1, i32 9, i32 2, i32 10, i32 3, i32 11, i32 4, i32 12, i32 5, i32 13, i32 6, i32 14, i32 7, i32 15>
+  ret <16 x float> %r
+}
+
+; PR86076
+define <16 x float> @shuffle_f32_v16f32_00_08_00_08_00_08_00_08_00_08_00_08_00_08_00_08(float %a0, float %a1) {
+; ALL-LABEL: shuffle_f32_v16f32_00_08_00_08_00_08_00_08_00_08_00_08_00_08_00_08:
+; ALL:       # %bb.0:
+; ALL-NEXT:    vinsertps {{.*#+}} xmm0 = xmm0[0],xmm1[0],zero,zero
+; ALL-NEXT:    vbroadcastsd %xmm0, %zmm0
+; ALL-NEXT:    retq
+  %v0 = insertelement <8 x float> poison, float %a0, i64 0
+  %v1 = insertelement <8 x float> poison, float %a1, i64 0
+  %sv = shufflevector <8 x float> %v0, <8 x float> %v1, <16 x i32> <i32 0, i32 8, i32 0, i32 8, i32 0, i32 8, i32 0, i32 8, i32 0, i32 8, i32 0, i32 8, i32 0, i32 8, i32 0, i32 8>
+  ret <16 x float> %sv
+}
+
 define <16 x i32> @shuffle_v16i32_00_00_00_00_00_00_00_00_00_00_00_00_00_00_00_00(<16 x i32> %a, <16 x i32> %b) {
 ; ALL-LABEL: shuffle_v16i32_00_00_00_00_00_00_00_00_00_00_00_00_00_00_00_00:
 ; ALL:       # %bb.0: