[llvm] [RISCV] Handle RVV return type in calling convention correctly (PR #87736)

[Roger Ferrer Ibáñez via llvm-commits]

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@@ -409,7 +409,7 @@ bool RISCVCallLowering::lowerReturnVal(MachineIRBuilder &MIRBuilder,
   splitToValueTypes(OrigRetInfo, SplitRetInfos, DL, CC);
 
   RVVArgDispatcher Dispatcher{&MF, getTLI<RISCVTargetLowering>(),
-                              F.getReturnType()};
+                              ArrayRef(F.getReturnType())};
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rofirrim wrote:

In this example you could explicitly set T in the call (`test<int>(1)`) but… you can't do that in a constructor call like in your case of `RVVArgDispatcher`, so I'm afraid the explicit cast will have to remain.

https://github.com/llvm/llvm-project/pull/87736