[PATCH] D25857: [tsan][clang] Introduce a function attribute to disable TSan checking at run time

[Dmitry Vyukov via cfe-commits]

dvyukov added inline comments.


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Comment at: lib/CodeGen/CodeGenFunction.cpp:717
 
+  // Ignore TSan memory acesses from within dealloc and all of its calees at
+  // run time.
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This is unpleasant. We had recursive ignores in the old Valgrind-based tsan, but managed to not reintroduce them in the new tsan so far. But I also don't see any better solution.



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Comment at: lib/CodeGen/CodeGenFunction.cpp:721
+    if (const auto *M = dyn_cast_or_null<ObjCMethodDecl>(D))
+      if (M->getMethodFamily() == OMF_dealloc)
+        Fn->addFnAttr("sanitize_thread_no_checking_at_run_time");
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Can we do this check right in the tsan pass? Or this information is already lost there?


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Comment at: lib/CodeGen/CodeGenFunction.cpp:722
+      if (M->getMethodFamily() == OMF_dealloc)
+        Fn->addFnAttr("sanitize_thread_no_checking_at_run_time");
+
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Also do:
   Fn->removeFnAttr(llvm::Attribute::SanitizeThread);
That's what will effectively happen. And it will allow to simplify the other patch.


https://reviews.llvm.org/D25857