[llvm] [PowerPC][AIX] Using milicode for memcmp instead of libcall (PR #147093)

[zhijian lin via llvm-commits]

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@@ -39,7 +39,7 @@ define noundef i32 @_Z11memcmp_testPKvS0_m(ptr noundef readonly captures(none) %
 ; CHECK-AIX-64-P9-NEXT:    mflr r0
 ; CHECK-AIX-64-P9-NEXT:    stdu r1, -112(r1)
 ; CHECK-AIX-64-P9-NEXT:    std r0, 128(r1)
-; CHECK-AIX-64-P9-NEXT:    bl .memcmp[PR]
+; CHECK-AIX-64-P9-NEXT:    bl .___memcmp64[PR]
 ; CHECK-AIX-64-P9-NEXT:    nop
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diggerlin wrote:

> @diggerlin: There should be no TOC modification/use for a call to a millicode routine. The `nop` is not necessary. Additionally, the branch can be `bla`. It seems that the tail call case should be tested after all?

LLVM does not support AIX tail calls yet. I think the bl will be changed to bla once LLVM supports AIX tail calls. I am currently working on adding AIX tail call support to LLVM.

https://github.com/llvm/llvm-project/pull/147093