[llvm] [PowerPC] support tail call optimization on AIX tail call (PR #161690)

[zhijian lin via llvm-commits]

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@@ -108,7 +108,7 @@ define dso_local void @print_func() {
 ; LINUX64BE-NEXT:    mtlr r0
 ; LINUX64BE-NEXT:    blr
 entry:
-  %call = tail call signext i32 @puts(ptr noundef nonnull dereferenceable(1) @.str)
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diggerlin wrote:

The tail call optimization only applies when the call instruction is the last instruction in the function. In this case, the IR call is not the final instruction, so the tail keyword has no effect. Therefore, I removed the tail as well.

https://github.com/llvm/llvm-project/pull/161690