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27 #include "IncrementalSweeper.h"
33 #include "MarkedBlock.h"
34 #include "ScopeChain.h"
35 #include <wtf/HashSet.h>
36 #include <wtf/WTFThreadData.h>
42 static const CFTimeInterval sweepTimeSlice = .01; // seconds
43 static const CFTimeInterval sweepTimeTotal = .10;
44 static const CFTimeInterval sweepTimeMultiplier = 1.0 / sweepTimeTotal;
46 void IncrementalSweeper::doWork()
48 doSweep(WTF::monotonicallyIncreasingTime());
51 IncrementalSweeper::IncrementalSweeper(Heap* heap, CFRunLoopRef runLoop)
52 : HeapTimer(heap->globalData(), runLoop)
53 , m_currentBlockToSweepIndex(0)
54 , m_structuresCanBeSwept(false)
58 IncrementalSweeper* IncrementalSweeper::create(Heap* heap)
60 return new IncrementalSweeper(heap, CFRunLoopGetCurrent());
63 void IncrementalSweeper::scheduleTimer()
65 CFRunLoopTimerSetNextFireDate(m_timer.get(), CFAbsoluteTimeGetCurrent() + (sweepTimeSlice * sweepTimeMultiplier));
68 void IncrementalSweeper::cancelTimer()
70 CFRunLoopTimerSetNextFireDate(m_timer.get(), CFAbsoluteTimeGetCurrent() + s_decade);
73 void IncrementalSweeper::doSweep(double sweepBeginTime)
75 while (m_currentBlockToSweepIndex < m_blocksToSweep.size()) {
78 CFTimeInterval elapsedTime = WTF::monotonicallyIncreasingTime() - sweepBeginTime;
79 if (elapsedTime < sweepTimeSlice)
86 m_blocksToSweep.clear();
90 void IncrementalSweeper::sweepNextBlock()
92 while (m_currentBlockToSweepIndex < m_blocksToSweep.size()) {
93 MarkedBlock* block = m_blocksToSweep[m_currentBlockToSweepIndex++];
94 if (block->onlyContainsStructures())
95 m_structuresCanBeSwept = true;
97 ASSERT(!m_structuresCanBeSwept);
99 if (!block->needsSweeping())
103 m_globalData->heap.objectSpace().freeOrShrinkBlock(block);
108 void IncrementalSweeper::startSweeping(const HashSet<MarkedBlock*>& blockSnapshot)
110 m_blocksToSweep.resize(blockSnapshot.size());
111 CopyFunctor functor(m_blocksToSweep);
112 m_globalData->heap.objectSpace().forEachBlock(functor);
113 m_currentBlockToSweepIndex = 0;
114 m_structuresCanBeSwept = false;
118 void IncrementalSweeper::willFinishSweeping()
120 m_currentBlockToSweepIndex = 0;
121 m_structuresCanBeSwept = true;
122 m_blocksToSweep.clear();
129 IncrementalSweeper::IncrementalSweeper(JSGlobalData* globalData)
130 : HeapTimer(globalData)
131 , m_structuresCanBeSwept(false)
135 void IncrementalSweeper::doWork()
139 IncrementalSweeper* IncrementalSweeper::create(Heap* heap)
141 return new IncrementalSweeper(heap->globalData());
144 void IncrementalSweeper::startSweeping(const HashSet<MarkedBlock*>&)
146 m_structuresCanBeSwept = false;
149 void IncrementalSweeper::willFinishSweeping()
151 m_structuresCanBeSwept = true;
154 void IncrementalSweeper::sweepNextBlock()
160 bool IncrementalSweeper::structuresCanBeSwept()
162 return m_structuresCanBeSwept;