[llvm] [AArch64][GlobalISel] Lower G_BUILD_VECTOR to G_INSERT_VECTOR_ELT (PR #105686)

[David Green via llvm-commits]

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@@ -10,12 +10,14 @@ define i32 @bar() {
 ; CHECK:       ; %bb.0: ; %bb
 ; CHECK-NEXT:    movi.2d v0, #0000000000000000
 ; CHECK-NEXT:    mov b1, v0[1]
-; CHECK-NEXT:    mov b2, v0[2]
-; CHECK-NEXT:    mov b3, v0[3]
-; CHECK-NEXT:    mov.h v0[1], v1[0]
-; CHECK-NEXT:    mov.h v2[1], v3[0]
+; CHECK-NEXT:    mov b2, v0[3]
+; CHECK-NEXT:    mov b3, v0[2]
+; CHECK-NEXT:    fmov w8, s1
+; CHECK-NEXT:    fmov w9, s2
+; CHECK-NEXT:    mov.h v0[1], w8
+; CHECK-NEXT:    mov.h v3[1], w9
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davemgreen wrote:

When we went through all the changes in this pr, we decided this one should be using a vector any_ext. (And the zero's should all optimize away).

https://github.com/llvm/llvm-project/pull/105686