[llvm] [GISEL][RISCV] Add G_VACOPY GISEL opcode and add lowering code for it. (PR #73066)

[Matt Arsenault via llvm-commits]

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@@ -86,6 +88,10 @@ RISCVLegalizerInfo::RISCVLegalizerInfo(const RISCVSubtarget &ST) {
     unsigned BigTyIdx = Op == G_MERGE_VALUES ? 0 : 1;
     unsigned LitTyIdx = Op == G_MERGE_VALUES ? 1 : 0;
     getActionDefinitionsBuilder(Op)
+        .legalIf([=, &ST](const LegalityQuery &Query) -> bool {
+          return ST.hasStdExtD() && typeIs(LitTyIdx, s32)(Query) &&
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arsenm wrote:

Should add the legalIf for hasStdExtD, not have the check inside the callback 

https://github.com/llvm/llvm-project/pull/73066