[llvm] [RISCV] Make RISCVVPseudo extend Pseudo. NFC (PR #149785)

[Craig Topper via llvm-commits]

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@@ -543,7 +543,8 @@ defset list<VTypeInfoToWide> AllWidenableBFloatToFloatVectors = {
 // This represents the information we need in codegen for each pseudo.
 // The definition should be consistent with `struct PseudoInfo` in
 // RISCVInstrInfo.h.
-class RISCVVPseudo {
+class RISCVVPseudo<dag outs, dag ins, list<dag> pattern, string opcodestr = "", string argstr = "">
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topperc wrote:

Should we default `pattern` to `[]`?

https://github.com/llvm/llvm-project/pull/149785