[llvm] [PowerPC] Add special handling for arguments that are smaller than pointer size. (PR #119003)

[Hubert Tong via llvm-commits]

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@@ -7291,7 +7294,21 @@ SDValue PPCTargetLowering::LowerFormalArguments_AIX(
       SDValue FIN = DAG.getFrameIndex(FI, PtrVT);
       SDValue ArgValue =
           DAG.getLoad(ValVT, dl, Chain, FIN, MachinePointerInfo());
-      InVals.push_back(ArgValue);
+
+      // While the ABI specifies that the higher bits of the load should be
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hubert-reinterpretcast wrote:

More typo/grammar fixes:
While the ABI specifies the argument type is (sign or zero) extended out to register width, not all code is compliant. We truncate and re-extend to be more forgiving of these callers when the argument type is smaller than register width.



https://github.com/llvm/llvm-project/pull/119003