[llvm] [AArch64][GlobalISel] Fast-path simple common calls (NFC) (PR #217615)

[Nathan Corbyn via llvm-commits]

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@@ -1513,7 +1569,11 @@ bool AArch64CallLowering::lowerCall(MachineIRBuilder &MIRBuilder,
     AArch64OutgoingValueAssigner Assigner(RetAssignFn, RetAssignFn, Subtarget,
                                           /*IsReturn*/ false);
     ReturnedArgCallReturnHandler ReturnedArgHandler(MIRBuilder, MRI, MIB);
-    if (!determineAndHandleAssignments(
+    bool AssignedCallReturn =
+        Info.CallConv == CallingConv::C && !UsingReturnedArg &&
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cofibrant wrote:

I guess I haven't understood the significance of the `!UsingReturnArg` here vs in the above...

https://github.com/llvm/llvm-project/pull/217615