[llvm] [PowerPC] Fix vector_shuffle combines when inputs are scalar_to_vector of differing types. (PR #80784)

[zhijian lin via llvm-commits]

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@@ -266,56 +266,54 @@ entry:
 define <16 x i8> @test_v16i8_v8i16(i16 %arg, i8 %arg1) {
 ; CHECK-LE-P8-LABEL: test_v16i8_v8i16:
 ; CHECK-LE-P8:       # %bb.0: # %entry
-; CHECK-LE-P8-NEXT:    mtfprd f0, r4
-; CHECK-LE-P8-NEXT:    xxswapd v2, vs0
-; CHECK-LE-P8-NEXT:    mtfprd f0, r3
-; CHECK-LE-P8-NEXT:    xxswapd v3, vs0
-; CHECK-LE-P8-NEXT:    vmrglh v2, v3, v2
+; CHECK-LE-P8-NEXT:    mtvsrd v2, r4
+; CHECK-LE-P8-NEXT:    mtvsrd v3, r3
+; CHECK-LE-P8-NEXT:    vmrghh v2, v3, v2
 ; CHECK-LE-P8-NEXT:    blr
 ;
 ; CHECK-LE-P9-LABEL: test_v16i8_v8i16:
 ; CHECK-LE-P9:       # %bb.0: # %entry
-; CHECK-LE-P9-NEXT:    mtfprd f0, r4
-; CHECK-LE-P9-NEXT:    xxswapd v2, vs0
-; CHECK-LE-P9-NEXT:    mtfprd f0, r3
-; CHECK-LE-P9-NEXT:    xxswapd v3, vs0
-; CHECK-LE-P9-NEXT:    vmrglh v2, v3, v2
+; CHECK-LE-P9-NEXT:    mtvsrd v2, r4
+; CHECK-LE-P9-NEXT:    mtvsrd v3, r3
+; CHECK-LE-P9-NEXT:    vmrghh v2, v3, v2
 ; CHECK-LE-P9-NEXT:    blr
 ;
 ; CHECK-BE-P8-LABEL: test_v16i8_v8i16:
 ; CHECK-BE-P8:       # %bb.0: # %entry
-; CHECK-BE-P8-NEXT:    sldi r4, r4, 56
-; CHECK-BE-P8-NEXT:    sldi r3, r3, 48
-; CHECK-BE-P8-NEXT:    mtvsrd v2, r4
-; CHECK-BE-P8-NEXT:    mtvsrd v3, r3
-; CHECK-BE-P8-NEXT:    vmrghh v2, v2, v3
+; CHECK-BE-P8-NEXT:    mtvsrwz v3, r3
+; CHECK-BE-P8-NEXT:    addis r3, r2, .LCPI3_0 at toc@ha
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diggerlin wrote:

I am curious . there is no read data from TC entry, but the right has the read data from TC entry, but the PR look not related to TC entry ?

https://github.com/llvm/llvm-project/pull/80784