[clang] [compiler-rt] [llvm] [AIX] Implement the ifunc attribute. (PR #153049)

[Wael Yehia via cfe-commits]

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@@ -1547,6 +1547,9 @@ class TargetInfo : public TransferrableTargetInfo,
       return true;
     if (getTriple().getArch() == llvm::Triple::ArchType::avr)
       return true;
+    if (getTriple().isOSAIX())
+      return getTriple().getOSMajorVersion() == 0 ||
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w2yehia wrote:

`getTriple().getOSMajorVersion() == 0` occurs if the user manually passes a triple without an OS version, i.e. `--target=powerpc64-ibm-aix-xcoff`.
By default, the compiler computes the first two digits of the four-digit AIX OS version and passes it in the triple, e.g. `-cc1 -triple powerpc64-ibm-aix7.2.0.0`. We are not able to get more accurate (the last two digits) version info at runtime.

https://github.com/llvm/llvm-project/pull/153049