1/*
2 * Copyright (C) 2017 Apple Inc. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
16 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR
17 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
18 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
19 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
20 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
21 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
23 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26#pragma once
27
28#include "FreeList.h"
29#include "MarkedBlock.h"
30
31namespace JSC {
32
33template<typename Func>
34ALWAYS_INLINE HeapCell* FreeList::allocate(const Func& slowPath)
35{
36 unsigned remaining = m_remaining;
37 if (remaining) {
38 unsigned cellSize = m_cellSize;
39 remaining -= cellSize;
40 m_remaining = remaining;
41 return bitwise_cast<HeapCell*>(m_payloadEnd - remaining - cellSize);
42 }
43
44 FreeCell* result = head();
45 if (UNLIKELY(!result))
46 return slowPath();
47
48 m_scrambledHead = result->scrambledNext;
49 return bitwise_cast<HeapCell*>(result);
50}
51
52template<typename Func>
53void FreeList::forEach(const Func& func) const
54{
55 if (m_remaining) {
56 for (unsigned remaining = m_remaining; remaining; remaining -= m_cellSize)
57 func(bitwise_cast<HeapCell*>(m_payloadEnd - remaining));
58 } else {
59 for (FreeCell* cell = head(); cell;) {
60 // We can use this to overwrite free objects before destroying the free list. So, we need
61 // to get next before proceeding further.
62 FreeCell* next = cell->next(m_secret);
63 func(bitwise_cast<HeapCell*>(cell));
64 cell = next;
65 }
66 }
67}
68
69} // namespace JSC
70
71