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

[Wael Yehia via llvm-commits]

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@@ -146,26 +146,9 @@ void aix::Linker::ConstructJob(Compilation &C, const JobAction &JA,
     CmdArgs.push_back("-bforceimprw");
   }
 
-  // PGO instrumentation generates symbols belonging to special sections, and
-  // the linker needs to place all symbols in a particular section together in
-  // memory; the AIX linker does that under an option.
-  if (Args.hasFlag(options::OPT_fprofile_arcs, options::OPT_fno_profile_arcs,
-                    false) ||
-       Args.hasFlag(options::OPT_fprofile_generate,
-                    options::OPT_fno_profile_generate, false) ||
-       Args.hasFlag(options::OPT_fprofile_generate_EQ,
-                    options::OPT_fno_profile_generate, false) ||
-       Args.hasFlag(options::OPT_fprofile_instr_generate,
-                    options::OPT_fno_profile_instr_generate, false) ||
-       Args.hasFlag(options::OPT_fprofile_instr_generate_EQ,
-                    options::OPT_fno_profile_instr_generate, false) ||
-       Args.hasFlag(options::OPT_fcs_profile_generate,
-                    options::OPT_fno_profile_generate, false) ||
-       Args.hasFlag(options::OPT_fcs_profile_generate_EQ,
-                    options::OPT_fno_profile_generate, false) ||
-       Args.hasArg(options::OPT_fcreate_profile) ||
-       Args.hasArg(options::OPT_coverage))
-    CmdArgs.push_back("-bdbg:namedsects:ss");
+  // ifunc support, which is ON by default, generates named sections.
----------------
w2yehia wrote:

added comment on what AIX version supports it. Unfortunately we are not able to detect the TL (VersionTuple::Subminor) and SP levels (the 3rd and 4th numbers in an AIX version string) at runtime accurately, so we will simply check if it's >= 7.2.0.0. Also improved comment

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