Thread-safety analysis: Add support for selectively turning off warnings

within part of a particular method.

llvm-svn: 163397

1 files changed, 84 insertions, 4 deletions

diff --git a/clang/test/SemaCXX/warn-thread-safety-analysis.cpp b/clang/test/SemaCXX/warn-thread-safety-analysis.cpp
index cf378c50907..6044b790217 100644
--- a/clang/test/SemaCXX/warn-thread-safety-analysis.cpp
+++ b/clang/test/SemaCXX/warn-thread-safety-analysis.cpp
@@ -24,10 +24,6 @@
   __attribute__ ((shared_locks_required(__VA_ARGS__)))
 #define NO_THREAD_SAFETY_ANALYSIS  __attribute__ ((no_thread_safety_analysis))
 
-//-----------------------------------------//
-//  Helper fields
-//-----------------------------------------//
-
 
 class  __attribute__((lockable)) Mutex {
  public:
@@ -60,6 +56,14 @@ class SCOPED_LOCKABLE ReleasableMutexLock {
 };
 
 
+// The universal lock, written "*", allows checking to be selectively turned
+// off for a particular piece of code.
+void beginNoWarnOnReads()  SHARED_LOCK_FUNCTION("*");
+void endNoWarnOnReads()    UNLOCK_FUNCTION("*");
+void beginNoWarnOnWrites() EXCLUSIVE_LOCK_FUNCTION("*");
+void endNoWarnOnWrites()   UNLOCK_FUNCTION("*");
+
+
 template<class T>
 class SmartPtr {
 public:
@@ -3217,3 +3221,79 @@ static void test() {
 }
 
 
+namespace UniversalLock {
+
+class Foo {
+  Mutex mu_;
+  bool c;
+
+  int a        GUARDED_BY(mu_);
+  void r_foo() SHARED_LOCKS_REQUIRED(mu_);
+  void w_foo() EXCLUSIVE_LOCKS_REQUIRED(mu_);
+
+  void test1() {
+    int b;
+
+    beginNoWarnOnReads();
+    b = a;
+    r_foo();
+    endNoWarnOnReads();
+
+    beginNoWarnOnWrites();
+    a = 0;
+    w_foo();
+    endNoWarnOnWrites();
+  }
+
+  // don't warn on joins with universal lock
+  void test2() {
+    if (c) {
+      beginNoWarnOnWrites();
+    }
+    a = 0; // \
+      // expected-warning {{writing variable 'a' requires locking 'mu_' exclusively}}
+    endNoWarnOnWrites();  // \
+      // expected-warning {{unlocking '*' that was not locked}}
+  }
+
+
+  // make sure the universal lock joins properly
+  void test3() {
+    if (c) {
+      mu_.Lock();
+      beginNoWarnOnWrites();
+    }
+    else {
+      beginNoWarnOnWrites();
+      mu_.Lock();
+    }
+    a = 0;
+    endNoWarnOnWrites();
+    mu_.Unlock();
+  }
+
+
+  // combine universal lock with other locks
+  void test4() {
+    beginNoWarnOnWrites();
+    mu_.Lock();
+    mu_.Unlock();
+    endNoWarnOnWrites();
+
+    mu_.Lock();
+    beginNoWarnOnWrites();
+    endNoWarnOnWrites();
+    mu_.Unlock();
+
+    mu_.Lock();
+    beginNoWarnOnWrites();
+    mu_.Unlock();
+    endNoWarnOnWrites();
+  }
+};
+
+}
+
+
+
+