[llvm] [LLVM][rtsan] Add RealtimeSanitizer transform pass (PR #101232)

[Fangrui Song via llvm-commits]

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@@ -0,0 +1,35 @@
+; RUN: opt < %s -passes=rtsan -S | FileCheck %s
+
+; Function Attrs: mustprogress noinline nonblocking optnone ssp uwtable(sync)
+define void @violation() #0 {
+  %1 = alloca ptr, align 8
+  %2 = call ptr @malloc(i64 noundef 2) #3
+  store ptr %2, ptr %1, align 8
+  ret void
+}
+
+; Function Attrs: allocsize(0)
+declare ptr @malloc(i64 noundef) #1
+
+; Function Attrs: mustprogress noinline norecurse optnone ssp uwtable(sync)
+define noundef i32 @main() #2 {
+  %1 = alloca i32, align 4
+  store i32 0, ptr %1, align 4
+  call void @violation() #4
+  ret i32 0
+}
+
+attributes #0 = { mustprogress noinline nonblocking optnone ssp uwtable(sync) }
+attributes #1 = { allocsize(0) }
+attributes #2 = { mustprogress noinline norecurse optnone ssp uwtable(sync) }
+attributes #3 = { allocsize(0) }
+attributes #4 = { nonblocking }
+
+; RealtimeSanitizer pass should insert __rtsan_realtime_enter right after function definition
+; CHECK: define{{.*}}violation
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MaskRay wrote:

For functions, `@violation(` is preferred (also used by `llvm/utils/update_cc_test_checks.py`). This helps avoids ambiguity when you have `@foo` and `@foo2`

https://github.com/llvm/llvm-project/pull/101232