[tsan] Add interceptors and sychronization for libdispatch semaphores on OS X

This patch adds release and acquire semantics for libdispatch semaphores and a test case.

Differential Revision: http://reviews.llvm.org/D14992



git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@254412 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 29 insertions, 0 deletions

diff --git a/test/tsan/Darwin/gcd-semaphore-norace.mm b/test/tsan/Darwin/gcd-semaphore-norace.mm
new file mode 100644
index 000000000..cd52a79ca
--- /dev/null
+++ b/test/tsan/Darwin/gcd-semaphore-norace.mm
@@ -0,0 +1,29 @@
+// RUN: %clang_tsan %s -o %t -framework Foundation
+// RUN: %run %t 2>&1
+
+#import <Foundation/Foundation.h>
+
+long global;
+
+int main() {
+    NSLog(@"Hello world.");
+
+    global = 42;
+    
+    dispatch_semaphore_t sem = dispatch_semaphore_create(0);
+    dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
+        
+        global = 43;
+        dispatch_semaphore_signal(sem);
+    });
+    
+    dispatch_semaphore_wait(sem, DISPATCH_TIME_FOREVER);
+    global = 44;
+
+    NSLog(@"Done.");
+    return 0;
+}
+
+// CHECK: Hello world.
+// CHECK: Done.
+// CHECK-NOT: WARNING: ThreadSanitizer