[clang] [clang][rtsan] Introduce realtime sanitizer clang codegen and -fsanitize flag (PR #100192)

[Fangrui Song via cfe-commits]

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@@ -1410,6 +1414,35 @@ QualType CodeGenFunction::BuildFunctionArgList(GlobalDecl GD,
   return ResTy;
 }
 
+void InsertCallBeforeInstruction(llvm::Function *Fn,
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MaskRay wrote:

Code style wise: https://llvm.org/docs/CodingStandards.html#anonymous-namespaces Use static for internal linkage functions. LLVM code is more consistent in that most functions use `functionName` while clang is more inconsistent (a lot of `FunctionName`). When moved to LLVM, make sure that the case is changed.

https://github.com/llvm/llvm-project/pull/100192