[clang] [llvm] [PowerPC][AIX] Support #pragma comment copyright for AIX (PR #178184)

[Tony Varghese via cfe-commits]

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@@ -1700,6 +1701,13 @@ PassBuilder::buildModuleOptimizationPipeline(OptimizationLevel Level,
           InlineContext{ThinOrFullLTOPhase::None, InlinePass::CGSCCInliner}));
     }
   }
+
+  // Lower !comment_string.loadtime metadata to a concrete TU-local string
+  // global and attach !implicit.ref to all defined functions. Running late
+  // ensures compiler-generated functions (e.g. from inlining, coroutines)
+  // are also anchored to the copyright string via .ref directives.
+  MPM.addPass(LowerCommentStringPass());
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tonykuttai wrote:

Primary motivation was to convert `!comment_string.loadtime` metadata to LLVM IR earlier in the pipeline. Also it needs to run in both pre-link and post-link LTO phases, which is simpler in opt. The pass itself is bailed out early for non-aix targets.  Having it in the general pipeline makes future extension much easier. update `isSupportedTarget()` when adding z/OS or other targets that need similar load-time comment functionality.

https://github.com/llvm/llvm-project/pull/178184