// RUN: %clang -target x86_64-linux-gnu -S -emit-llvm -o - %s | FileCheck -check-prefixes CHECK,WITHOUT %s // RUN: %clang -target x86_64-linux-gnu -S -emit-llvm -o - %s -fsanitize=thread | FileCheck -check-prefixes CHECK,TSAN %s // Instrumented function. // TSan inserts calls to __tsan_func_entry() and __tsan_func_exit() to prologue/epilogue. // Non-atomic loads are instrumented with __tsan_readXXX(), atomic loads - with // __tsan_atomicXXX_load(). // // CHECK-LABEL: @instrumented1 // TSAN: call void @__tsan_func_entry // WITHOUT-NOT: call void @__tsan_func_entry // TSAN: call void @__tsan_read4 // WITHOUT-NOT: call void @__tsan_read4 // TSAN: call i32 @__tsan_atomic32_load // WITHOUT-NOT: call i32 @__tsan_atomic32_load // TSAN: call void @__tsan_func_exit // WITHOUT-NOT: call void @__tsan_func_exit // CHECK: ret i32 int instrumented1(int *a, _Atomic int *b) { return *a + *b; } // Function with no_sanitize("thread"). // TSan only inserts instrumentation necessary to prevent false positives: calls are inserted for // function entry/exit and atomics, but not plain memory accesses. // // CHECK-LABEL: @no_false_positives1 // TSAN: call void @__tsan_func_entry // WITHOUT-NOT: call void @__tsan_func_entry // TSAN-NOT: call void @__tsan_read4 // WITHOUT-NOT: call void @__tsan_read4 // TSAN: call i32 @__tsan_atomic32_load // WITHOUT-NOT: call i32 @__tsan_atomic32_load // TSAN: call void @__tsan_func_exit // WITHOUT-NOT: call void @__tsan_func_exit // CHECK: ret i32 __attribute__((no_sanitize("thread"))) int no_false_positives1(int *a, _Atomic int *b) { return *a + *b; } // Function with disable_sanitizer_instrumentation: no instrumentation at all. // // CHECK-LABEL: @no_instrumentation1 // TSAN-NOT: call void @__tsan_func_entry // WITHOUT-NOT: call void @__tsan_func_entry // TSAN-NOT: call void @__tsan_read4 // WITHOUT-NOT: call void @__tsan_read4 // TSAN-NOT: call i32 @__tsan_atomic32_load // WITHOUT-NOT: call i32 @__tsan_atomic32_load // TSAN-NOT: call void @__tsan_func_exit // WITHOUT-NOT: call void @__tsan_func_exit // CHECK: ret i32 __attribute__((disable_sanitizer_instrumentation)) int no_instrumentation1(int *a, _Atomic int *b) { return *a + *b; }