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

[Hubert Tong via llvm-commits]

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@@ -1185,69 +1185,69 @@ define i64 @test_ints_stack(i32 %i1, i32 %i2, i32 %i3, i32 %i4, i32 %i5, i32 %i6
 ; ASM32PWR4-LABEL: test_ints_stack:
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hubert-reinterpretcast wrote:

> It does seem that this PR departs from other AIX compilers in that it actually clears all but the least significant bit. Other AIX compilers treat this case the same as the `i8 zeroext` case.

This has been resolved with the changes; thanks @stefanp-ibm!

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