[clang] [clang-scan-deps] Fix contention when updating `TrackingStatistic`s in hot code paths in `FileManager`. (PR #88427)

[Jan Svoboda via cfe-commits]

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@@ -1293,6 +1293,10 @@ compileModuleImpl(CompilerInstance &ImportingInstance, SourceLocation ImportLoc,
                                             diag::remark_module_build_done)
     << ModuleName;
 
+  // Propagate the statistics to the parent FileManager.
+  if (FrontendOpts.ModulesShareFileManager)
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jansvoboda11 wrote:

Shouldn't this condition be inverted? When `FrontendOpts.ModulesShareFileManager == true`, I'd expect `&ImportingInstance.getFileManager() == &Instance.getFileManager()`. Maybe we can have an assertion in `FileManager::AddStats()` that would catch this.

https://github.com/llvm/llvm-project/pull/88427