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

[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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RolandF77 wrote:

What does removing the tail attribute accomplish? Also a number of those cases are the last real instruction, with only a return after which returns void or the call result. and those should be possible.

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