[llvm] [RISCV] Add codegen support for ri.vinsert.v.x and ri.vextract.x.v (PR #136708)

[Luke Lau via llvm-commits]

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@@ -9576,6 +9576,13 @@ getSmallestVTForIndex(MVT VecVT, unsigned MaxIdx, SDLoc DL, SelectionDAG &DAG,
   return SmallerVT;
 }
 
+static bool isValidInsertExtractIndex(SDValue Idx) {
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lukel97 wrote:

Nit, name this something that explicitly mentions Visni?

https://github.com/llvm/llvm-project/pull/136708