[clang] [llvm] [LLVM][rtsan] Add module pass to initialize rtsan (PR #118989)

[Vitaly Buka via llvm-commits]

================
@@ -1024,12 +1024,14 @@ void EmitAssemblyHelper::RunOptimizationPipeline(
             FPM.addPass(BoundsCheckingPass());
           });
 
-    if (LangOpts.Sanitize.has(SanitizerKind::Realtime))
+    if (LangOpts.Sanitize.has(SanitizerKind::Realtime)) {
----------------
vitalybuka wrote:

You need to consider performance vs quality.

For other sanitizers it's essentially:
1. If it's early - better precision - in sense we detect issues in C/C++ program which can be optimized out. (can Realtime related issue be optimized out, and do you care about them at all)
2. If it's late - better performance, but we may miss bugs
I believe performance is ~2x difference, so we can't afford that e.g. in Asan.


https://github.com/llvm/llvm-project/pull/118989