Demangle [[clang::blocking]] function names in rtsan pass

Author: davidtrevelyan

llvm/lib/Transforms/Instrumentation/RealtimeSanitizer.cpp

@@ -17,6 +17,7 @@
 #include "llvm/IR/IRBuilder.h"
 #include "llvm/IR/Module.h"
 
+#include "llvm/Demangle/Demangle.h"
 #include "llvm/Transforms/Instrumentation/RealtimeSanitizer.h"
 
 using namespace llvm;
@@ -53,7 +54,7 @@ static PreservedAnalyses rtsanPreservedCFGAnalyses() {
 
 static void insertExpectNotRealtimeAtFunctionEntryPoint(Function &F) {
   IRBuilder<> Builder(&F.front().front());
-  Value *NameArg = Builder.CreateGlobalString(F.getName());
+  Value *NameArg = Builder.CreateGlobalString(demangle(F.getName()));
 
   FunctionType *FuncType =
       FunctionType::get(Type::getVoidTy(F.getContext()),

llvm/test/Instrumentation/RealtimeSanitizer/rtsan_unsafe.ll

@@ -1,16 +1,19 @@
 ; RUN: opt < %s -passes=rtsan -S | FileCheck %s
 
-define void @blocking_function() #0 {
+define void @_Z17blocking_functionv() #0 {
   ret void
 }
 
 define noundef i32 @main() #2 {
-  call void @blocking_function() #4
+  call void @_Z17blocking_functionv() #4
   ret i32 0
 }
 
 attributes #0 = { mustprogress noinline sanitize_realtime_unsafe optnone ssp uwtable(sync) }
 
-; RealtimeSanitizer pass should insert __rtsan_expect_not_realtime at function entrypoint
-; CHECK-LABEL: @blocking_function()
-; CHECK-NEXT: call{{.*}}@__rtsan_expect_not_realtime({{ptr .*}})
+; RealtimeSanitizer pass should create the demangled function name as a global string, and
+; pass it as input to an inserted __rtsan_expect_not_realtime call at the function entrypoint
+; CHECK: [[GLOBAL_STR:@[a-zA-Z0-9\.]+]]
+; CHECK-SAME: c"blocking_function()\00"
+; CHECK-LABEL: @_Z17blocking_functionv()
+; CHECK-NEXT: call{{.*}}@__rtsan_expect_not_realtime(ptr{{.*}}[[GLOBAL_STR]])