[llvm] [RISCV][ISel] Combine vector fadd/fsub/fmul with fp extend. (PR #81248)

[via llvm-commits]

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@@ -13292,12 +13292,15 @@ namespace {
 // apply a combine.
 struct CombineResult;
 
+enum ExtKind : uint8_t { ZExt = 1 << 0, SExt = 1 << 1, FPExt = 1 << 2 };
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sun-jacobi wrote:

It is for refactoring the `canFoldToVWWithSameExtensionImpl`, advised by @wangpc-pp.

https://github.com/llvm/llvm-project/pull/81248