Changeset 118587 in webkit

Timestamp:

May 25, 2012 4:46:28 PM (12 years ago)

Author:

mitz@apple.com

Message:

Make the ICU-based implementation of NonSharedCharacterBreakIterator work in configurations
that do not have COMPARE_AND_SWAP enabled.

Reviewed by Jessie Berlin.

• platform/text/TextBreakIteratorICU.cpp:

(WebCore::compareAndSwapNonSharedCharacterBreakIterator): Added this helper. It uses
weakCompareAndSwap when COMPARE_AND_SWAP is enabled, and uses a mutex to do the atomic
compare and swap otherwise.
(WebCore::NonSharedCharacterBreakIterator::NonSharedCharacterBreakIterator): Changed to use
compareAndSwapNonSharedCharacterBreakIterator().
(WebCore::NonSharedCharacterBreakIterator::~NonSharedCharacterBreakIterator): Ditto.

Location:

trunk/Source/WebCore

Files:

• ChangeLog (modified) (1 diff)
• platform/text/TextBreakIteratorICU.cpp (modified) (2 diffs)

trunk/Source/WebCore/ChangeLog

@@ +1 @@
+2012-05-25  Dan Bernstein  <mitz@apple.com>
+
+        Make the ICU-based implementation of NonSharedCharacterBreakIterator work in configurations
+        that do not have COMPARE_AND_SWAP enabled.
+
+        Reviewed by Jessie Berlin.
+
+        * platform/text/TextBreakIteratorICU.cpp:
+        (WebCore::compareAndSwapNonSharedCharacterBreakIterator): Added this helper. It uses
+        weakCompareAndSwap when COMPARE_AND_SWAP is enabled, and uses a mutex to do the atomic
+        compare and swap otherwise.
+        (WebCore::NonSharedCharacterBreakIterator::NonSharedCharacterBreakIterator): Changed to use
+        compareAndSwapNonSharedCharacterBreakIterator().
+        (WebCore::NonSharedCharacterBreakIterator::~NonSharedCharacterBreakIterator): Ditto.
+
 2012-05-25  Tommy Widenflycht  <tommyw@google.com>
 

trunk/Source/WebCore/platform/text/TextBreakIteratorICU.cpp

@@ -88 +88 @@
 static TextBreakIterator* nonSharedCharacterBreakIterator;
 
+static inline bool compareAndSwapNonSharedCharacterBreakIterator(TextBreakIterator* expected, TextBreakIterator* newValue)
+{
+#if ENABLE(COMPARE_AND_SWAP)
+    return weakCompareAndSwap(reinterpret_cast<void**>(&nonSharedCharacterBreakIterator), expected, newValue);
+#else
+    DEFINE_STATIC_LOCAL(Mutex, nonSharedCharacterBreakIteratorMutex, ());
+    MutexLocker locker(nonSharedCharacterBreakIteratorMutex);
+    if (nonSharedCharacterBreakIterator != expected)
+        return false;
+    nonSharedCharacterBreakIterator = newValue;
+    return true;
+#endif
+}
+
 NonSharedCharacterBreakIterator::NonSharedCharacterBreakIterator(const UChar* buffer, int length)
 {
     m_iterator = nonSharedCharacterBreakIterator;
-    bool createdIterator = m_iterator && weakCompareAndSwap(reinterpret_cast<void**>(&nonSharedCharacterBreakIterator), m_iterator, 0);
+    bool createdIterator = m_iterator && compareAndSwapNonSharedCharacterBreakIterator(m_iterator, 0);
     m_iterator = setUpIterator(createdIterator, m_iterator, UBRK_CHARACTER, buffer, length);
 }
@@ -97 +111 @@
 NonSharedCharacterBreakIterator::~NonSharedCharacterBreakIterator()
 {
-    if (!weakCompareAndSwap(reinterpret_cast<void**>(&nonSharedCharacterBreakIterator), 0, m_iterator))
+    if (!compareAndSwapNonSharedCharacterBreakIterator(0, m_iterator))
         ubrk_close(reinterpret_cast<UBreakIterator*>(m_iterator));
 }