1 files changed, 107 insertions, 0 deletions
diff --git a/Source/JavaScriptCore/heap/IncrementalSweeper.cpp b/Source/JavaScriptCore/heap/IncrementalSweeper.cpp
new file mode 100644
index 000000000..08a9f6c73
--- /dev/null
+++ b/Source/JavaScriptCore/heap/IncrementalSweeper.cpp
@@ -0,0 +1,107 @@
+#include "config.h"
+#include "IncrementalSweeper.h"
+
+#include "APIShims.h"
+#include "Heap.h"
+#include "JSObject.h"
+#include "JSString.h"
+#include "MarkedBlock.h"
+#include "ScopeChain.h"
+#include <wtf/HashSet.h>
+#include <wtf/WTFThreadData.h>
+
+namespace JSC {
+
+#if USE(CF)
+
+static const CFTimeInterval decade = 60 * 60 * 24 * 365 * 10;
+static const CFTimeInterval sweepTimeSlicePerBlock = 0.01;
+static const CFTimeInterval sweepTimeMultiplier = 1.0 / sweepTimeSlicePerBlock;
+ 
+void IncrementalSweeper::timerDidFire(CFRunLoopTimerRef, void* info)
+{
+    Heap* heap = static_cast<Heap*>(info);
+    APIEntryShim shim(heap->globalData());
+    heap->sweeper()->doSweep(WTF::monotonicallyIncreasingTime());
+}
+    
+IncrementalSweeper::IncrementalSweeper(Heap* heap, CFRunLoopRef runLoop)
+    : m_heap(heap)
+    , m_currentBlockToSweepIndex(0)
+    , m_lengthOfLastSweepIncrement(0.0)
+{
+    memset(&m_context, 0, sizeof(CFRunLoopTimerContext));
+    m_context.info = m_heap;
+    m_runLoop = runLoop;
+    m_timer.adoptCF(CFRunLoopTimerCreate(0, CFAbsoluteTimeGetCurrent(), decade, 0, 0, &timerDidFire, &m_context));
+    CFRunLoopAddTimer(m_runLoop.get(), m_timer.get(), kCFRunLoopCommonModes);
+}
+
+IncrementalSweeper::~IncrementalSweeper()
+{
+    CFRunLoopRemoveTimer(m_runLoop.get(), m_timer.get(), kCFRunLoopCommonModes);
+    CFRunLoopTimerInvalidate(m_timer.get());
+}
+
+PassOwnPtr<IncrementalSweeper> IncrementalSweeper::create(Heap* heap)
+{
+    return adoptPtr(new IncrementalSweeper(heap, CFRunLoopGetCurrent()));
+}
+
+void IncrementalSweeper::scheduleTimer()
+{
+    CFRunLoopTimerSetNextFireDate(m_timer.get(), CFAbsoluteTimeGetCurrent() + (m_lengthOfLastSweepIncrement * sweepTimeMultiplier));
+}
+
+void IncrementalSweeper::cancelTimer()
+{
+    CFRunLoopTimerSetNextFireDate(m_timer.get(), CFAbsoluteTimeGetCurrent() + decade);
+}
+
+void IncrementalSweeper::doSweep(double sweepBeginTime)
+{
+    for (; m_currentBlockToSweepIndex < m_blocksToSweep.size(); m_currentBlockToSweepIndex++) {
+        MarkedBlock* nextBlock = m_blocksToSweep[m_currentBlockToSweepIndex];
+        if (!nextBlock->needsSweeping())
+            continue;
+
+        nextBlock->sweep();
+        m_blocksToSweep[m_currentBlockToSweepIndex++] = 0;
+        m_lengthOfLastSweepIncrement = WTF::monotonicallyIncreasingTime() - sweepBeginTime;
+        scheduleTimer();
+        return;
+    }
+
+    m_blocksToSweep.clear();
+    cancelTimer();
+}
+
+void IncrementalSweeper::startSweeping(const HashSet<MarkedBlock*>& blockSnapshot)
+{
+    WTF::copyToVector(blockSnapshot, m_blocksToSweep);
+    m_currentBlockToSweepIndex = 0;
+    scheduleTimer();
+}
+
+#else
+
+IncrementalSweeper::IncrementalSweeper()
+{
+}
+
+IncrementalSweeper::~IncrementalSweeper()
+{
+}
+
+PassOwnPtr<IncrementalSweeper> IncrementalSweeper::create(Heap*)
+{
+    return adoptPtr(new IncrementalSweeper());
+}
+
+void IncrementalSweeper::startSweeping(const HashSet<MarkedBlock*>&)
+{
+}
+    
+#endif
+
+} // namespace JSC