[llvm] [RISCV][GISEL] instruction-select for G_SPLAT_VECTOR (PR #111193)

[Thorsten Schütt via llvm-commits]

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@@ -67,7 +67,428 @@ define <vscale x 64 x i1> @splat_zero_nxv64i1() {
   ret <vscale x 64 x i1> zeroinitializer
 }
 
+define <vscale x 1 x i8> @splat_zero_nxv1i8() {
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tschuett wrote:

Do you mean:
```
def insert_vector_element_extract_vector_element : GICombineRule<
   (defs root:$root),
   (match (G_EXTRACT_VECTOR_ELT $elt, $src, $idx),
          (G_INSERT_VECTOR_ELT $root, $src, $elt, $idx)),
   (apply (GIReplaceReg $root, $src))>;
```
?

https://github.com/llvm/llvm-project/pull/111193