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27 #include "ConservativeRoots.h"
31 inline bool isPointerAligned(void* p)
33 return !((intptr_t)(p) & (sizeof(char*) - 1));
36 void ConservativeRoots::grow()
38 size_t newCapacity = m_capacity == inlineCapacity ? nonInlineCapacity : m_capacity * 2;
39 JSCell** newRoots = static_cast<JSCell**>(OSAllocator::reserveAndCommit(newCapacity * sizeof(JSCell*)));
40 memcpy(newRoots, m_roots, m_size * sizeof(JSCell*));
41 if (m_roots != m_inlineRoots)
42 OSAllocator::decommitAndRelease(m_roots, m_capacity * sizeof(JSCell*));
43 m_capacity = newCapacity;
47 inline void ConservativeRoots::add(void* p, TinyBloomFilter filter)
49 MarkedBlock* candidate = MarkedBlock::blockFor(p);
50 if (filter.ruleOut(reinterpret_cast<Bits>(candidate))) {
51 ASSERT(!candidate || !m_blocks->set().contains(candidate));
55 if (!MarkedBlock::isAtomAligned(p))
58 if (!m_blocks->set().contains(candidate))
61 // The conservative set inverts the typical meaning of mark bits: We only
62 // visit marked pointers, and our visit clears the mark bit. This efficiently
63 // sifts out pointers to dead objects and duplicate pointers.
64 if (!candidate->testAndClearMarked(p))
67 if (m_size == m_capacity)
70 m_roots[m_size++] = static_cast<JSCell*>(p);
73 void ConservativeRoots::add(void* begin, void* end)
76 ASSERT((static_cast<char*>(end) - static_cast<char*>(begin)) < 0x1000000);
77 ASSERT(isPointerAligned(begin));
78 ASSERT(isPointerAligned(end));
80 TinyBloomFilter filter = m_blocks->filter(); // Make a local copy of filter to show the compiler it won't alias, and can be register-allocated.
81 for (char** it = static_cast<char**>(begin); it != static_cast<char**>(end); ++it)