1// Licensed to the .NET Foundation under one or more agreements.
2// The .NET Foundation licenses this file to you under the MIT license.
3// See the LICENSE file in the project root for more information.
4
5#include <stdint.h>
6#include <windows.h>
7#include "debugmacros.h"
8#include "iallocator.h"
9#include "gcinfoarraylist.h"
10#include "safemath.h"
11
12inline size_t roundUp(size_t size, size_t alignment)
13{
14 // `alignment` must be a power of two
15 assert(alignment != 0);
16 assert((alignment & (alignment - 1)) == 0);
17
18 return (size + (alignment - 1)) & ~(alignment - 1);
19}
20
21GcInfoArrayListBase::GcInfoArrayListBase(IAllocator* allocator)
22 : m_allocator(allocator),
23 m_firstChunk(nullptr),
24 m_lastChunk(nullptr),
25 m_lastChunkCount(0),
26 m_lastChunkCapacity(0),
27 m_itemCount(0)
28{
29 assert(m_allocator != nullptr);
30}
31
32GcInfoArrayListBase::~GcInfoArrayListBase()
33{
34 for (ChunkBase* list = m_firstChunk, *chunk; list != nullptr; list = chunk)
35 {
36 chunk = list->m_next;
37 m_allocator->Free(list);
38 }
39}
40
41void GcInfoArrayListBase::AppendNewChunk(size_t firstChunkCapacity, size_t elementSize, size_t chunkAlignment)
42{
43 size_t chunkCapacity = (m_firstChunk == nullptr) ? firstChunkCapacity : (m_lastChunkCapacity * GrowthFactor);
44
45 S_SIZE_T chunkSize = S_SIZE_T(roundUp(sizeof(ChunkBase), chunkAlignment)) + (S_SIZE_T(elementSize) * S_SIZE_T(chunkCapacity));
46 assert(!chunkSize.IsOverflow());
47
48 ChunkBase* chunk = reinterpret_cast<ChunkBase*>(m_allocator->Alloc(chunkSize.Value()));
49 chunk->m_next = nullptr;
50
51 if (m_lastChunk != nullptr)
52 {
53 assert(m_firstChunk != nullptr);
54 m_lastChunk->m_next = chunk;
55 }
56 else
57 {
58 assert(m_lastChunk == nullptr);
59 m_firstChunk = chunk;
60 }
61
62 m_lastChunk = chunk;
63 m_lastChunkCount = 0;
64 m_lastChunkCapacity = chunkCapacity;
65}
66
67GcInfoArrayListBase::IteratorBase::IteratorBase(GcInfoArrayListBase* list, size_t firstChunkCapacity)
68 : m_list(list)
69{
70 assert(m_list != nullptr);
71
72 // Note: if the list is empty, m_list->firstChunk == nullptr == m_list->lastChunk and m_lastChunkCount == 0.
73 // In that case, the next two lines will set m_currentChunk to nullptr and m_currentChunkCount to 0.
74 m_currentChunk = m_list->m_firstChunk;
75 m_currentChunkCount = (m_currentChunk == m_list->m_lastChunk) ? m_list->m_lastChunkCount : firstChunkCapacity;
76}
77
78GcInfoArrayListBase::ChunkBase* GcInfoArrayListBase::IteratorBase::GetNextChunk(size_t& elementCount)
79{
80 if (m_currentChunk == nullptr)
81 {
82 elementCount = 0;
83 return nullptr;
84 }
85
86 ChunkBase* chunk = m_currentChunk;
87 elementCount = m_currentChunkCount;
88
89 m_currentChunk = m_currentChunk->m_next;
90 if (m_currentChunk == nullptr)
91 {
92 m_currentChunkCount = 0;
93 }
94 else if (m_currentChunk == m_list->m_lastChunk)
95 {
96 m_currentChunkCount = m_list->m_lastChunkCount;
97 }
98 else
99 {
100 m_currentChunkCount *= GrowthFactor;
101 }
102
103 return chunk;
104}
105