[tsan] Synchronize leaving a GCD group with notifications

In the patch that introduced support for GCD barrier blocks, I removed releasing a group when leaving it (in dispatch_group_leave). However, this is necessary to synchronize leaving a group and a notification callback (dispatch_group_notify). Adding this back, simplifying dispatch_group_notify_f and adding a test case.

Differential Revision: http://reviews.llvm.org/D21927



git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@274549 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 56 insertions, 0 deletions

diff --git a/test/tsan/Darwin/gcd-groups-leave.mm b/test/tsan/Darwin/gcd-groups-leave.mm
new file mode 100644
index 000000000..6ecf85f5f
--- /dev/null
+++ b/test/tsan/Darwin/gcd-groups-leave.mm
@@ -0,0 +1,56 @@
+// RUN: %clang_tsan %s -o %t -framework Foundation
+// RUN: %env_tsan_opts=ignore_interceptors_accesses=1 %run %t 2>&1 | FileCheck %s
+
+#import <Foundation/Foundation.h>
+
+#import "../test.h"
+
+dispatch_semaphore_t sem;
+
+long global;
+long global2;
+
+void callback(void *context) {
+  global2 = 48;
+  barrier_wait(&barrier);
+
+  dispatch_semaphore_signal(sem);
+}
+
+int main() {
+  fprintf(stderr, "Hello world.\n");
+  barrier_init(&barrier, 2);
+
+  dispatch_queue_t q = dispatch_queue_create("my.queue", DISPATCH_QUEUE_CONCURRENT);
+  dispatch_group_t g = dispatch_group_create();
+  sem = dispatch_semaphore_create(0);
+
+  dispatch_group_enter(g);
+  dispatch_async(q, ^{
+    global = 47;
+    dispatch_group_leave(g);
+    barrier_wait(&barrier);
+  });
+  dispatch_group_notify(g, q, ^{
+    global = 48;
+    barrier_wait(&barrier);
+
+    dispatch_semaphore_signal(sem);
+  });
+  dispatch_semaphore_wait(sem, DISPATCH_TIME_FOREVER);
+
+  dispatch_group_enter(g);
+  dispatch_async(q, ^{
+    global2 = 47;
+    dispatch_group_leave(g);
+    barrier_wait(&barrier);
+  });
+  dispatch_group_notify_f(g, q, NULL, &callback);
+  dispatch_semaphore_wait(sem, DISPATCH_TIME_FOREVER);
+
+  fprintf(stderr, "Done.\n");
+}
+
+// CHECK: Hello world.
+// CHECK-NOT: WARNING: ThreadSanitizer
+// CHECK: Done.