[llvm] [RISCV][GISEL] Legalize G_VAARG through expansion. (PR #73065)

[Matt Arsenault via llvm-commits]

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@@ -7868,6 +7870,63 @@ LegalizerHelper::lowerVectorReduction(MachineInstr &MI) {
   return UnableToLegalize;
 }
 
+static Type *getTypeForLLT(LLT Ty, LLVMContext &C);
+
+LegalizerHelper::LegalizeResult LegalizerHelper::lowerVAArg(MachineInstr &MI) {
+  Observer.changingInstr(MI);
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arsenm wrote:

You don't change the instruction, you create new ones and erase the original 

https://github.com/llvm/llvm-project/pull/73065