[llvm] [RISCV][GISel] Add FP calling convention support using FPR and GPR registers. (PR #69138)

[Philip Reames via llvm-commits]

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@@ -164,44 +194,101 @@ struct RISCVIncomingValueHandler : public CallLowering::IncomingValueHandler {
 
   void assignValueToReg(Register ValVReg, Register PhysReg,
                         CCValAssign VA) override {
-    // Copy argument received in physical register to desired VReg.
-    MIRBuilder.getMBB().addLiveIn(PhysReg);
-    MIRBuilder.buildCopy(ValVReg, PhysReg);
+    markPhysRegUsed(PhysReg);
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preames wrote:

Correct me if I'm wrong, but it looks like this plus a couple lines below in terms of changing  markPhysRegUsed definitions is an NFC-esq refactoring?  Can it be landed separately?

https://github.com/llvm/llvm-project/pull/69138