[clang] [llvm] [PowerPC] Add an alias for -mregnames so that full register names used in assembly. (PR #70255)

[Fangrui Song via cfe-commits]

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@@ -5011,6 +5011,12 @@ void Clang::ConstructJob(Compilation &C, const JobAction &JA,
     Args.AddLastArg(CmdArgs, options::OPT_fthinlto_index_EQ);
   }
 
+  if (Triple.isPPC())
+    if (const Arg *A =
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MaskRay wrote:

use `AddOptInFlag`

https://github.com/llvm/llvm-project/pull/70255