[llvm] [ctx_prof] "Use" support for pre-thinlink. (PR #101338)

[Mircea Trofin via llvm-commits]

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@@ -1176,8 +1180,11 @@ PassBuilder::buildModuleSimplificationPipeline(OptimizationLevel Level,
   // Enable contextual profiling instrumentation.
   const bool IsCtxProfGen = !IsPGOInstrGen && IsPreLink &&
                             PGOCtxProfLoweringPass::isContextualIRPGOEnabled();
+  const bool IsCtxProfUse = !UseCtxProfile.empty() && !PGOOpt &&
+                            Phase == ThinOrFullLTOPhase::ThinLTOPreLink;
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mtrofin wrote:

But `IsPreLink` is actually "Is not post-link". `None` also passes. With the current way, we also exclude the full LTO case, IIUC.

We could rename `IsPreLink` because it's really `IsNotPostThinLink`, wdyt?


https://github.com/llvm/llvm-project/pull/101338