Optimize QMutexPool

Make the get() function inline
and simplify the hash computation

Reviewed-by: brad

2 files changed, 19 insertions, 13 deletions

diff --git a/src/corelib/thread/qmutexpool.cpp b/src/corelib/thread/qmutexpool.cpp
index 13e29c3..144fa35 100644
--- a/src/corelib/thread/qmutexpool.cpp
+++ b/src/corelib/thread/qmutexpool.cpp
@@ -123,22 +123,20 @@ QMutexPool *QMutexPool::instance()
     return globalMutexPool();
 }
 
-/*!
+/*!  \fn QMutexPool::get(void *address)
     Returns a QMutex from the pool. QMutexPool uses the value \a address
     to determine which mutex is returned from the pool.
 */
-QMutex *QMutexPool::get(const void *address)
-{
-    Q_ASSERT_X(address != 0, "QMutexPool::get()", "'address' argument cannot be zero");
-    int index = int((quintptr(address) >> (sizeof(address) >> 1)) % mutexes.count());
-
-    if (!mutexes[index]) {
-        // mutex not created, create one
-        QMutex *newMutex = new QMutex(recursionMode);
-        if (!mutexes[index].testAndSetOrdered(0, newMutex))
-            delete newMutex;
-    }
 
+/*! \internal
+  create the mutex for the given index
+ */
+QMutex *QMutexPool::createMutex(int index)
+{
+    // mutex not created, create one
+    QMutex *newMutex = new QMutex(recursionMode);
+    if (!mutexes[index].testAndSetOrdered(0, newMutex))
+        delete newMutex;
     return mutexes[index];
 }
 
diff --git a/src/corelib/thread/qmutexpool_p.h b/src/corelib/thread/qmutexpool_p.h
index 1a45ba9..b2cd210 100644
--- a/src/corelib/thread/qmutexpool_p.h
+++ b/src/corelib/thread/qmutexpool_p.h
@@ -67,11 +67,19 @@ public:
     explicit QMutexPool(QMutex::RecursionMode recursionMode = QMutex::NonRecursive, int size = 131);
     ~QMutexPool();
 
-    QMutex *get(const void *address);
+    inline QMutex *get(const void *address) {
+        int index = uint(quintptr(address)) % mutexes.count();
+        QMutex *m = mutexes[index];
+        if (m)
+            return m;
+        else
+            return createMutex(index);
+    }
     static QMutexPool *instance();
     static QMutex *globalInstanceGet(const void *address);
 
 private:
+    QMutex *createMutex(int index);
     QVarLengthArray<QAtomicPointer<QMutex>, 131> mutexes;
     QMutex::RecursionMode recursionMode;
 };