Ben Murdoch | 257744e | 2011-11-30 15:57:28 +0000 | [diff] [blame] | 1 | // Copyright 2011 the V8 project authors. All rights reserved. |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2 | // Use of this source code is governed by a BSD-style license that can be |
| 3 | // found in the LICENSE file. |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 4 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 5 | #ifndef V8_HEAP_SPACES_H_ |
| 6 | #define V8_HEAP_SPACES_H_ |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 7 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 8 | #include "src/allocation.h" |
| 9 | #include "src/base/atomicops.h" |
| 10 | #include "src/base/bits.h" |
| 11 | #include "src/base/platform/mutex.h" |
| 12 | #include "src/hashmap.h" |
| 13 | #include "src/list.h" |
| 14 | #include "src/log.h" |
| 15 | #include "src/utils.h" |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 16 | |
| 17 | namespace v8 { |
| 18 | namespace internal { |
| 19 | |
Steve Block | 44f0eee | 2011-05-26 01:26:41 +0100 | [diff] [blame] | 20 | class Isolate; |
| 21 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 22 | // ----------------------------------------------------------------------------- |
| 23 | // Heap structures: |
| 24 | // |
| 25 | // A JS heap consists of a young generation, an old generation, and a large |
| 26 | // object space. The young generation is divided into two semispaces. A |
| 27 | // scavenger implements Cheney's copying algorithm. The old generation is |
| 28 | // separated into a map space and an old object space. The map space contains |
| 29 | // all (and only) map objects, the rest of old objects go into the old space. |
| 30 | // The old generation is collected by a mark-sweep-compact collector. |
| 31 | // |
| 32 | // The semispaces of the young generation are contiguous. The old and map |
Ben Murdoch | 7f4d5bd | 2010-06-15 11:15:29 +0100 | [diff] [blame] | 33 | // spaces consists of a list of pages. A page has a page header and an object |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 34 | // area. |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 35 | // |
| 36 | // There is a separate large object space for objects larger than |
| 37 | // Page::kMaxHeapObjectSize, so that they do not have to move during |
Ben Murdoch | 7f4d5bd | 2010-06-15 11:15:29 +0100 | [diff] [blame] | 38 | // collection. The large object space is paged. Pages in large object space |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 39 | // may be larger than the page size. |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 40 | // |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 41 | // A store-buffer based write barrier is used to keep track of intergenerational |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 42 | // references. See heap/store-buffer.h. |
Ben Murdoch | 7f4d5bd | 2010-06-15 11:15:29 +0100 | [diff] [blame] | 43 | // |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 44 | // During scavenges and mark-sweep collections we sometimes (after a store |
| 45 | // buffer overflow) iterate intergenerational pointers without decoding heap |
| 46 | // object maps so if the page belongs to old pointer space or large object |
| 47 | // space it is essential to guarantee that the page does not contain any |
| 48 | // garbage pointers to new space: every pointer aligned word which satisfies |
| 49 | // the Heap::InNewSpace() predicate must be a pointer to a live heap object in |
| 50 | // new space. Thus objects in old pointer and large object spaces should have a |
| 51 | // special layout (e.g. no bare integer fields). This requirement does not |
| 52 | // apply to map space which is iterated in a special fashion. However we still |
| 53 | // require pointer fields of dead maps to be cleaned. |
Ben Murdoch | 7f4d5bd | 2010-06-15 11:15:29 +0100 | [diff] [blame] | 54 | // |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 55 | // To enable lazy cleaning of old space pages we can mark chunks of the page |
| 56 | // as being garbage. Garbage sections are marked with a special map. These |
| 57 | // sections are skipped when scanning the page, even if we are otherwise |
| 58 | // scanning without regard for object boundaries. Garbage sections are chained |
| 59 | // together to form a free list after a GC. Garbage sections created outside |
| 60 | // of GCs by object trunctation etc. may not be in the free list chain. Very |
| 61 | // small free spaces are ignored, they need only be cleaned of bogus pointers |
| 62 | // into new space. |
Ben Murdoch | 7f4d5bd | 2010-06-15 11:15:29 +0100 | [diff] [blame] | 63 | // |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 64 | // Each page may have up to one special garbage section. The start of this |
| 65 | // section is denoted by the top field in the space. The end of the section |
| 66 | // is denoted by the limit field in the space. This special garbage section |
| 67 | // is not marked with a free space map in the data. The point of this section |
| 68 | // is to enable linear allocation without having to constantly update the byte |
| 69 | // array every time the top field is updated and a new object is created. The |
| 70 | // special garbage section is not in the chain of garbage sections. |
| 71 | // |
| 72 | // Since the top and limit fields are in the space, not the page, only one page |
| 73 | // has a special garbage section, and if the top and limit are equal then there |
| 74 | // is no special garbage section. |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 75 | |
| 76 | // Some assertion macros used in the debugging mode. |
| 77 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 78 | #define DCHECK_PAGE_ALIGNED(address) \ |
| 79 | DCHECK((OffsetFrom(address) & Page::kPageAlignmentMask) == 0) |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 80 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 81 | #define DCHECK_OBJECT_ALIGNED(address) \ |
| 82 | DCHECK((OffsetFrom(address) & kObjectAlignmentMask) == 0) |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 83 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 84 | #define DCHECK_OBJECT_SIZE(size) \ |
| 85 | DCHECK((0 < size) && (size <= Page::kMaxRegularHeapObjectSize)) |
Leon Clarke | e46be81 | 2010-01-19 14:06:41 +0000 | [diff] [blame] | 86 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 87 | #define DCHECK_PAGE_OFFSET(offset) \ |
| 88 | DCHECK((Page::kObjectStartOffset <= offset) && (offset <= Page::kPageSize)) |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 89 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 90 | #define DCHECK_MAP_PAGE_INDEX(index) \ |
| 91 | DCHECK((0 <= index) && (index <= MapSpace::kMaxMapPageIndex)) |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 92 | |
| 93 | |
| 94 | class PagedSpace; |
| 95 | class MemoryAllocator; |
| 96 | class AllocationInfo; |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 97 | class Space; |
| 98 | class FreeList; |
| 99 | class MemoryChunk; |
| 100 | |
| 101 | class MarkBit { |
| 102 | public: |
| 103 | typedef uint32_t CellType; |
| 104 | |
| 105 | inline MarkBit(CellType* cell, CellType mask, bool data_only) |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 106 | : cell_(cell), mask_(mask), data_only_(data_only) {} |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 107 | |
| 108 | inline CellType* cell() { return cell_; } |
| 109 | inline CellType mask() { return mask_; } |
| 110 | |
| 111 | #ifdef DEBUG |
| 112 | bool operator==(const MarkBit& other) { |
| 113 | return cell_ == other.cell_ && mask_ == other.mask_; |
| 114 | } |
| 115 | #endif |
| 116 | |
| 117 | inline void Set() { *cell_ |= mask_; } |
| 118 | inline bool Get() { return (*cell_ & mask_) != 0; } |
| 119 | inline void Clear() { *cell_ &= ~mask_; } |
| 120 | |
| 121 | inline bool data_only() { return data_only_; } |
| 122 | |
| 123 | inline MarkBit Next() { |
| 124 | CellType new_mask = mask_ << 1; |
| 125 | if (new_mask == 0) { |
| 126 | return MarkBit(cell_ + 1, 1, data_only_); |
| 127 | } else { |
| 128 | return MarkBit(cell_, new_mask, data_only_); |
| 129 | } |
| 130 | } |
| 131 | |
| 132 | private: |
| 133 | CellType* cell_; |
| 134 | CellType mask_; |
| 135 | // This boolean indicates that the object is in a data-only space with no |
| 136 | // pointers. This enables some optimizations when marking. |
| 137 | // It is expected that this field is inlined and turned into control flow |
| 138 | // at the place where the MarkBit object is created. |
| 139 | bool data_only_; |
| 140 | }; |
| 141 | |
| 142 | |
| 143 | // Bitmap is a sequence of cells each containing fixed number of bits. |
| 144 | class Bitmap { |
| 145 | public: |
| 146 | static const uint32_t kBitsPerCell = 32; |
| 147 | static const uint32_t kBitsPerCellLog2 = 5; |
| 148 | static const uint32_t kBitIndexMask = kBitsPerCell - 1; |
| 149 | static const uint32_t kBytesPerCell = kBitsPerCell / kBitsPerByte; |
| 150 | static const uint32_t kBytesPerCellLog2 = kBitsPerCellLog2 - kBitsPerByteLog2; |
| 151 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 152 | static const size_t kLength = (1 << kPageSizeBits) >> (kPointerSizeLog2); |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 153 | |
| 154 | static const size_t kSize = |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 155 | (1 << kPageSizeBits) >> (kPointerSizeLog2 + kBitsPerByteLog2); |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 156 | |
| 157 | |
| 158 | static int CellsForLength(int length) { |
| 159 | return (length + kBitsPerCell - 1) >> kBitsPerCellLog2; |
| 160 | } |
| 161 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 162 | int CellsCount() { return CellsForLength(kLength); } |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 163 | |
| 164 | static int SizeFor(int cells_count) { |
| 165 | return sizeof(MarkBit::CellType) * cells_count; |
| 166 | } |
| 167 | |
| 168 | INLINE(static uint32_t IndexToCell(uint32_t index)) { |
| 169 | return index >> kBitsPerCellLog2; |
| 170 | } |
| 171 | |
| 172 | INLINE(static uint32_t CellToIndex(uint32_t index)) { |
| 173 | return index << kBitsPerCellLog2; |
| 174 | } |
| 175 | |
| 176 | INLINE(static uint32_t CellAlignIndex(uint32_t index)) { |
| 177 | return (index + kBitIndexMask) & ~kBitIndexMask; |
| 178 | } |
| 179 | |
| 180 | INLINE(MarkBit::CellType* cells()) { |
| 181 | return reinterpret_cast<MarkBit::CellType*>(this); |
| 182 | } |
| 183 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 184 | INLINE(Address address()) { return reinterpret_cast<Address>(this); } |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 185 | |
| 186 | INLINE(static Bitmap* FromAddress(Address addr)) { |
| 187 | return reinterpret_cast<Bitmap*>(addr); |
| 188 | } |
| 189 | |
| 190 | inline MarkBit MarkBitFromIndex(uint32_t index, bool data_only = false) { |
| 191 | MarkBit::CellType mask = 1 << (index & kBitIndexMask); |
| 192 | MarkBit::CellType* cell = this->cells() + (index >> kBitsPerCellLog2); |
| 193 | return MarkBit(cell, mask, data_only); |
| 194 | } |
| 195 | |
| 196 | static inline void Clear(MemoryChunk* chunk); |
| 197 | |
| 198 | static void PrintWord(uint32_t word, uint32_t himask = 0) { |
| 199 | for (uint32_t mask = 1; mask != 0; mask <<= 1) { |
| 200 | if ((mask & himask) != 0) PrintF("["); |
| 201 | PrintF((mask & word) ? "1" : "0"); |
| 202 | if ((mask & himask) != 0) PrintF("]"); |
| 203 | } |
| 204 | } |
| 205 | |
| 206 | class CellPrinter { |
| 207 | public: |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 208 | CellPrinter() : seq_start(0), seq_type(0), seq_length(0) {} |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 209 | |
| 210 | void Print(uint32_t pos, uint32_t cell) { |
| 211 | if (cell == seq_type) { |
| 212 | seq_length++; |
| 213 | return; |
| 214 | } |
| 215 | |
| 216 | Flush(); |
| 217 | |
| 218 | if (IsSeq(cell)) { |
| 219 | seq_start = pos; |
| 220 | seq_length = 0; |
| 221 | seq_type = cell; |
| 222 | return; |
| 223 | } |
| 224 | |
| 225 | PrintF("%d: ", pos); |
| 226 | PrintWord(cell); |
| 227 | PrintF("\n"); |
| 228 | } |
| 229 | |
| 230 | void Flush() { |
| 231 | if (seq_length > 0) { |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 232 | PrintF("%d: %dx%d\n", seq_start, seq_type == 0 ? 0 : 1, |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 233 | seq_length * kBitsPerCell); |
| 234 | seq_length = 0; |
| 235 | } |
| 236 | } |
| 237 | |
| 238 | static bool IsSeq(uint32_t cell) { return cell == 0 || cell == 0xFFFFFFFF; } |
| 239 | |
| 240 | private: |
| 241 | uint32_t seq_start; |
| 242 | uint32_t seq_type; |
| 243 | uint32_t seq_length; |
| 244 | }; |
| 245 | |
| 246 | void Print() { |
| 247 | CellPrinter printer; |
| 248 | for (int i = 0; i < CellsCount(); i++) { |
| 249 | printer.Print(i, cells()[i]); |
| 250 | } |
| 251 | printer.Flush(); |
| 252 | PrintF("\n"); |
| 253 | } |
| 254 | |
| 255 | bool IsClean() { |
| 256 | for (int i = 0; i < CellsCount(); i++) { |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 257 | if (cells()[i] != 0) { |
| 258 | return false; |
| 259 | } |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 260 | } |
| 261 | return true; |
| 262 | } |
| 263 | }; |
| 264 | |
| 265 | |
| 266 | class SkipList; |
| 267 | class SlotsBuffer; |
| 268 | |
| 269 | // MemoryChunk represents a memory region owned by a specific space. |
| 270 | // It is divided into the header and the body. Chunk start is always |
| 271 | // 1MB aligned. Start of the body is aligned so it can accommodate |
| 272 | // any heap object. |
| 273 | class MemoryChunk { |
| 274 | public: |
| 275 | // Only works if the pointer is in the first kPageSize of the MemoryChunk. |
| 276 | static MemoryChunk* FromAddress(Address a) { |
| 277 | return reinterpret_cast<MemoryChunk*>(OffsetFrom(a) & ~kAlignmentMask); |
| 278 | } |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 279 | static const MemoryChunk* FromAddress(const byte* a) { |
| 280 | return reinterpret_cast<const MemoryChunk*>(OffsetFrom(a) & |
| 281 | ~kAlignmentMask); |
| 282 | } |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 283 | |
| 284 | // Only works for addresses in pointer spaces, not data or code spaces. |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 285 | static inline MemoryChunk* FromAnyPointerAddress(Heap* heap, Address addr); |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 286 | |
| 287 | Address address() { return reinterpret_cast<Address>(this); } |
| 288 | |
| 289 | bool is_valid() { return address() != NULL; } |
| 290 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 291 | MemoryChunk* next_chunk() const { |
| 292 | return reinterpret_cast<MemoryChunk*>(base::Acquire_Load(&next_chunk_)); |
| 293 | } |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 294 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 295 | MemoryChunk* prev_chunk() const { |
| 296 | return reinterpret_cast<MemoryChunk*>(base::Acquire_Load(&prev_chunk_)); |
| 297 | } |
| 298 | |
| 299 | void set_next_chunk(MemoryChunk* next) { |
| 300 | base::Release_Store(&next_chunk_, reinterpret_cast<base::AtomicWord>(next)); |
| 301 | } |
| 302 | |
| 303 | void set_prev_chunk(MemoryChunk* prev) { |
| 304 | base::Release_Store(&prev_chunk_, reinterpret_cast<base::AtomicWord>(prev)); |
| 305 | } |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 306 | |
| 307 | Space* owner() const { |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 308 | if ((reinterpret_cast<intptr_t>(owner_) & kPageHeaderTagMask) == |
| 309 | kPageHeaderTag) { |
| 310 | return reinterpret_cast<Space*>(reinterpret_cast<intptr_t>(owner_) - |
| 311 | kPageHeaderTag); |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 312 | } else { |
| 313 | return NULL; |
| 314 | } |
| 315 | } |
| 316 | |
| 317 | void set_owner(Space* space) { |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 318 | DCHECK((reinterpret_cast<intptr_t>(space) & kPageHeaderTagMask) == 0); |
| 319 | owner_ = reinterpret_cast<Address>(space) + kPageHeaderTag; |
| 320 | DCHECK((reinterpret_cast<intptr_t>(owner_) & kPageHeaderTagMask) == |
| 321 | kPageHeaderTag); |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 322 | } |
| 323 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 324 | base::VirtualMemory* reserved_memory() { return &reservation_; } |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 325 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 326 | void InitializeReservedMemory() { reservation_.Reset(); } |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 327 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 328 | void set_reserved_memory(base::VirtualMemory* reservation) { |
| 329 | DCHECK_NOT_NULL(reservation); |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 330 | reservation_.TakeControl(reservation); |
| 331 | } |
| 332 | |
| 333 | bool scan_on_scavenge() { return IsFlagSet(SCAN_ON_SCAVENGE); } |
| 334 | void initialize_scan_on_scavenge(bool scan) { |
| 335 | if (scan) { |
| 336 | SetFlag(SCAN_ON_SCAVENGE); |
| 337 | } else { |
| 338 | ClearFlag(SCAN_ON_SCAVENGE); |
| 339 | } |
| 340 | } |
| 341 | inline void set_scan_on_scavenge(bool scan); |
| 342 | |
| 343 | int store_buffer_counter() { return store_buffer_counter_; } |
| 344 | void set_store_buffer_counter(int counter) { |
| 345 | store_buffer_counter_ = counter; |
| 346 | } |
| 347 | |
| 348 | bool Contains(Address addr) { |
| 349 | return addr >= area_start() && addr < area_end(); |
| 350 | } |
| 351 | |
| 352 | // Checks whether addr can be a limit of addresses in this page. |
| 353 | // It's a limit if it's in the page, or if it's just after the |
| 354 | // last byte of the page. |
| 355 | bool ContainsLimit(Address addr) { |
| 356 | return addr >= area_start() && addr <= area_end(); |
| 357 | } |
| 358 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 359 | // Every n write barrier invocations we go to runtime even though |
| 360 | // we could have handled it in generated code. This lets us check |
| 361 | // whether we have hit the limit and should do some more marking. |
| 362 | static const int kWriteBarrierCounterGranularity = 500; |
| 363 | |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 364 | enum MemoryChunkFlags { |
| 365 | IS_EXECUTABLE, |
| 366 | ABOUT_TO_BE_FREED, |
| 367 | POINTERS_TO_HERE_ARE_INTERESTING, |
| 368 | POINTERS_FROM_HERE_ARE_INTERESTING, |
| 369 | SCAN_ON_SCAVENGE, |
| 370 | IN_FROM_SPACE, // Mutually exclusive with IN_TO_SPACE. |
| 371 | IN_TO_SPACE, // All pages in new space has one of these two set. |
| 372 | NEW_SPACE_BELOW_AGE_MARK, |
| 373 | CONTAINS_ONLY_DATA, |
| 374 | EVACUATION_CANDIDATE, |
| 375 | RESCAN_ON_EVACUATION, |
| 376 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 377 | // WAS_SWEPT indicates that marking bits have been cleared by the sweeper, |
| 378 | // otherwise marking bits are still intact. |
| 379 | WAS_SWEPT, |
| 380 | |
| 381 | // Large objects can have a progress bar in their page header. These object |
| 382 | // are scanned in increments and will be kept black while being scanned. |
| 383 | // Even if the mutator writes to them they will be kept black and a white |
| 384 | // to grey transition is performed in the value. |
| 385 | HAS_PROGRESS_BAR, |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 386 | |
| 387 | // Last flag, keep at bottom. |
| 388 | NUM_MEMORY_CHUNK_FLAGS |
| 389 | }; |
| 390 | |
| 391 | |
| 392 | static const int kPointersToHereAreInterestingMask = |
| 393 | 1 << POINTERS_TO_HERE_ARE_INTERESTING; |
| 394 | |
| 395 | static const int kPointersFromHereAreInterestingMask = |
| 396 | 1 << POINTERS_FROM_HERE_ARE_INTERESTING; |
| 397 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 398 | static const int kEvacuationCandidateMask = 1 << EVACUATION_CANDIDATE; |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 399 | |
| 400 | static const int kSkipEvacuationSlotsRecordingMask = |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 401 | (1 << EVACUATION_CANDIDATE) | (1 << RESCAN_ON_EVACUATION) | |
| 402 | (1 << IN_FROM_SPACE) | (1 << IN_TO_SPACE); |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 403 | |
| 404 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 405 | void SetFlag(int flag) { flags_ |= static_cast<uintptr_t>(1) << flag; } |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 406 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 407 | void ClearFlag(int flag) { flags_ &= ~(static_cast<uintptr_t>(1) << flag); } |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 408 | |
| 409 | void SetFlagTo(int flag, bool value) { |
| 410 | if (value) { |
| 411 | SetFlag(flag); |
| 412 | } else { |
| 413 | ClearFlag(flag); |
| 414 | } |
| 415 | } |
| 416 | |
| 417 | bool IsFlagSet(int flag) { |
| 418 | return (flags_ & (static_cast<uintptr_t>(1) << flag)) != 0; |
| 419 | } |
| 420 | |
| 421 | // Set or clear multiple flags at a time. The flags in the mask |
| 422 | // are set to the value in "flags", the rest retain the current value |
| 423 | // in flags_. |
| 424 | void SetFlags(intptr_t flags, intptr_t mask) { |
| 425 | flags_ = (flags_ & ~mask) | (flags & mask); |
| 426 | } |
| 427 | |
| 428 | // Return all current flags. |
| 429 | intptr_t GetFlags() { return flags_; } |
| 430 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 431 | |
| 432 | // SWEEPING_DONE - The page state when sweeping is complete or sweeping must |
| 433 | // not be performed on that page. |
| 434 | // SWEEPING_FINALIZE - A sweeper thread is done sweeping this page and will |
| 435 | // not touch the page memory anymore. |
| 436 | // SWEEPING_IN_PROGRESS - This page is currently swept by a sweeper thread. |
| 437 | // SWEEPING_PENDING - This page is ready for parallel sweeping. |
| 438 | enum ParallelSweepingState { |
| 439 | SWEEPING_DONE, |
| 440 | SWEEPING_FINALIZE, |
| 441 | SWEEPING_IN_PROGRESS, |
| 442 | SWEEPING_PENDING |
| 443 | }; |
| 444 | |
| 445 | ParallelSweepingState parallel_sweeping() { |
| 446 | return static_cast<ParallelSweepingState>( |
| 447 | base::Acquire_Load(¶llel_sweeping_)); |
| 448 | } |
| 449 | |
| 450 | void set_parallel_sweeping(ParallelSweepingState state) { |
| 451 | base::Release_Store(¶llel_sweeping_, state); |
| 452 | } |
| 453 | |
| 454 | bool TryParallelSweeping() { |
| 455 | return base::Acquire_CompareAndSwap(¶llel_sweeping_, SWEEPING_PENDING, |
| 456 | SWEEPING_IN_PROGRESS) == |
| 457 | SWEEPING_PENDING; |
| 458 | } |
| 459 | |
| 460 | bool SweepingCompleted() { return parallel_sweeping() <= SWEEPING_FINALIZE; } |
| 461 | |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 462 | // Manage live byte count (count of bytes known to be live, |
| 463 | // because they are marked black). |
| 464 | void ResetLiveBytes() { |
| 465 | if (FLAG_gc_verbose) { |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 466 | PrintF("ResetLiveBytes:%p:%x->0\n", static_cast<void*>(this), |
| 467 | live_byte_count_); |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 468 | } |
| 469 | live_byte_count_ = 0; |
| 470 | } |
| 471 | void IncrementLiveBytes(int by) { |
| 472 | if (FLAG_gc_verbose) { |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 473 | printf("UpdateLiveBytes:%p:%x%c=%x->%x\n", static_cast<void*>(this), |
| 474 | live_byte_count_, ((by < 0) ? '-' : '+'), ((by < 0) ? -by : by), |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 475 | live_byte_count_ + by); |
| 476 | } |
| 477 | live_byte_count_ += by; |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 478 | DCHECK_LE(static_cast<unsigned>(live_byte_count_), size_); |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 479 | } |
| 480 | int LiveBytes() { |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 481 | DCHECK(static_cast<unsigned>(live_byte_count_) <= size_); |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 482 | return live_byte_count_; |
| 483 | } |
| 484 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 485 | int write_barrier_counter() { |
| 486 | return static_cast<int>(write_barrier_counter_); |
| 487 | } |
| 488 | |
| 489 | void set_write_barrier_counter(int counter) { |
| 490 | write_barrier_counter_ = counter; |
| 491 | } |
| 492 | |
| 493 | int progress_bar() { |
| 494 | DCHECK(IsFlagSet(HAS_PROGRESS_BAR)); |
| 495 | return progress_bar_; |
| 496 | } |
| 497 | |
| 498 | void set_progress_bar(int progress_bar) { |
| 499 | DCHECK(IsFlagSet(HAS_PROGRESS_BAR)); |
| 500 | progress_bar_ = progress_bar; |
| 501 | } |
| 502 | |
| 503 | void ResetProgressBar() { |
| 504 | if (IsFlagSet(MemoryChunk::HAS_PROGRESS_BAR)) { |
| 505 | set_progress_bar(0); |
| 506 | ClearFlag(MemoryChunk::HAS_PROGRESS_BAR); |
| 507 | } |
| 508 | } |
| 509 | |
| 510 | bool IsLeftOfProgressBar(Object** slot) { |
| 511 | Address slot_address = reinterpret_cast<Address>(slot); |
| 512 | DCHECK(slot_address > this->address()); |
| 513 | return (slot_address - (this->address() + kObjectStartOffset)) < |
| 514 | progress_bar(); |
| 515 | } |
| 516 | |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 517 | static void IncrementLiveBytesFromGC(Address address, int by) { |
| 518 | MemoryChunk::FromAddress(address)->IncrementLiveBytes(by); |
| 519 | } |
| 520 | |
| 521 | static void IncrementLiveBytesFromMutator(Address address, int by); |
| 522 | |
| 523 | static const intptr_t kAlignment = |
| 524 | (static_cast<uintptr_t>(1) << kPageSizeBits); |
| 525 | |
| 526 | static const intptr_t kAlignmentMask = kAlignment - 1; |
| 527 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 528 | static const intptr_t kSizeOffset = 0; |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 529 | |
| 530 | static const intptr_t kLiveBytesOffset = |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 531 | kSizeOffset + kPointerSize + kPointerSize + kPointerSize + kPointerSize + |
| 532 | kPointerSize + kPointerSize + kPointerSize + kPointerSize + kIntSize; |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 533 | |
| 534 | static const size_t kSlotsBufferOffset = kLiveBytesOffset + kIntSize; |
| 535 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 536 | static const size_t kWriteBarrierCounterOffset = |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 537 | kSlotsBufferOffset + kPointerSize + kPointerSize; |
| 538 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 539 | static const size_t kHeaderSize = |
| 540 | kWriteBarrierCounterOffset + kPointerSize + kIntSize + kIntSize + |
| 541 | kPointerSize + 5 * kPointerSize + kPointerSize + kPointerSize; |
| 542 | |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 543 | static const int kBodyOffset = |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 544 | CODE_POINTER_ALIGN(kHeaderSize + Bitmap::kSize); |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 545 | |
| 546 | // The start offset of the object area in a page. Aligned to both maps and |
| 547 | // code alignment to be suitable for both. Also aligned to 32 words because |
| 548 | // the marking bitmap is arranged in 32 bit chunks. |
| 549 | static const int kObjectStartAlignment = 32 * kPointerSize; |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 550 | static const int kObjectStartOffset = |
| 551 | kBodyOffset - 1 + |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 552 | (kObjectStartAlignment - (kBodyOffset - 1) % kObjectStartAlignment); |
| 553 | |
| 554 | size_t size() const { return size_; } |
| 555 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 556 | void set_size(size_t size) { size_ = size; } |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 557 | |
| 558 | void SetArea(Address area_start, Address area_end) { |
| 559 | area_start_ = area_start; |
| 560 | area_end_ = area_end; |
| 561 | } |
| 562 | |
| 563 | Executability executable() { |
| 564 | return IsFlagSet(IS_EXECUTABLE) ? EXECUTABLE : NOT_EXECUTABLE; |
| 565 | } |
| 566 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 567 | bool ContainsOnlyData() { return IsFlagSet(CONTAINS_ONLY_DATA); } |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 568 | |
| 569 | bool InNewSpace() { |
| 570 | return (flags_ & ((1 << IN_FROM_SPACE) | (1 << IN_TO_SPACE))) != 0; |
| 571 | } |
| 572 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 573 | bool InToSpace() { return IsFlagSet(IN_TO_SPACE); } |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 574 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 575 | bool InFromSpace() { return IsFlagSet(IN_FROM_SPACE); } |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 576 | |
| 577 | // --------------------------------------------------------------------- |
| 578 | // Markbits support |
| 579 | |
| 580 | inline Bitmap* markbits() { |
| 581 | return Bitmap::FromAddress(address() + kHeaderSize); |
| 582 | } |
| 583 | |
| 584 | void PrintMarkbits() { markbits()->Print(); } |
| 585 | |
| 586 | inline uint32_t AddressToMarkbitIndex(Address addr) { |
| 587 | return static_cast<uint32_t>(addr - this->address()) >> kPointerSizeLog2; |
| 588 | } |
| 589 | |
| 590 | inline static uint32_t FastAddressToMarkbitIndex(Address addr) { |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 591 | const intptr_t offset = reinterpret_cast<intptr_t>(addr) & kAlignmentMask; |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 592 | |
| 593 | return static_cast<uint32_t>(offset) >> kPointerSizeLog2; |
| 594 | } |
| 595 | |
| 596 | inline Address MarkbitIndexToAddress(uint32_t index) { |
| 597 | return this->address() + (index << kPointerSizeLog2); |
| 598 | } |
| 599 | |
| 600 | void InsertAfter(MemoryChunk* other); |
| 601 | void Unlink(); |
| 602 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 603 | inline Heap* heap() const { return heap_; } |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 604 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 605 | static const int kFlagsOffset = kPointerSize; |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 606 | |
| 607 | bool IsEvacuationCandidate() { return IsFlagSet(EVACUATION_CANDIDATE); } |
| 608 | |
| 609 | bool ShouldSkipEvacuationSlotRecording() { |
| 610 | return (flags_ & kSkipEvacuationSlotsRecordingMask) != 0; |
| 611 | } |
| 612 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 613 | inline SkipList* skip_list() { return skip_list_; } |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 614 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 615 | inline void set_skip_list(SkipList* skip_list) { skip_list_ = skip_list; } |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 616 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 617 | inline SlotsBuffer* slots_buffer() { return slots_buffer_; } |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 618 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 619 | inline SlotsBuffer** slots_buffer_address() { return &slots_buffer_; } |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 620 | |
| 621 | void MarkEvacuationCandidate() { |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 622 | DCHECK(slots_buffer_ == NULL); |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 623 | SetFlag(EVACUATION_CANDIDATE); |
| 624 | } |
| 625 | |
| 626 | void ClearEvacuationCandidate() { |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 627 | DCHECK(slots_buffer_ == NULL); |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 628 | ClearFlag(EVACUATION_CANDIDATE); |
| 629 | } |
| 630 | |
| 631 | Address area_start() { return area_start_; } |
| 632 | Address area_end() { return area_end_; } |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 633 | int area_size() { return static_cast<int>(area_end() - area_start()); } |
| 634 | bool CommitArea(size_t requested); |
| 635 | |
| 636 | // Approximate amount of physical memory committed for this chunk. |
| 637 | size_t CommittedPhysicalMemory() { return high_water_mark_; } |
| 638 | |
| 639 | static inline void UpdateHighWaterMark(Address mark); |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 640 | |
| 641 | protected: |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 642 | size_t size_; |
| 643 | intptr_t flags_; |
| 644 | |
| 645 | // Start and end of allocatable memory on this chunk. |
| 646 | Address area_start_; |
| 647 | Address area_end_; |
| 648 | |
| 649 | // If the chunk needs to remember its memory reservation, it is stored here. |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 650 | base::VirtualMemory reservation_; |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 651 | // The identity of the owning space. This is tagged as a failure pointer, but |
| 652 | // no failure can be in an object, so this can be distinguished from any entry |
| 653 | // in a fixed array. |
| 654 | Address owner_; |
| 655 | Heap* heap_; |
| 656 | // Used by the store buffer to keep track of which pages to mark scan-on- |
| 657 | // scavenge. |
| 658 | int store_buffer_counter_; |
| 659 | // Count of bytes marked black on page. |
| 660 | int live_byte_count_; |
| 661 | SlotsBuffer* slots_buffer_; |
| 662 | SkipList* skip_list_; |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 663 | intptr_t write_barrier_counter_; |
| 664 | // Used by the incremental marker to keep track of the scanning progress in |
| 665 | // large objects that have a progress bar and are scanned in increments. |
| 666 | int progress_bar_; |
| 667 | // Assuming the initial allocation on a page is sequential, |
| 668 | // count highest number of bytes ever allocated on the page. |
| 669 | int high_water_mark_; |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 670 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 671 | base::AtomicWord parallel_sweeping_; |
| 672 | |
| 673 | // PagedSpace free-list statistics. |
| 674 | intptr_t available_in_small_free_list_; |
| 675 | intptr_t available_in_medium_free_list_; |
| 676 | intptr_t available_in_large_free_list_; |
| 677 | intptr_t available_in_huge_free_list_; |
| 678 | intptr_t non_available_small_blocks_; |
| 679 | |
| 680 | static MemoryChunk* Initialize(Heap* heap, Address base, size_t size, |
| 681 | Address area_start, Address area_end, |
| 682 | Executability executable, Space* owner); |
| 683 | |
| 684 | private: |
| 685 | // next_chunk_ holds a pointer of type MemoryChunk |
| 686 | base::AtomicWord next_chunk_; |
| 687 | // prev_chunk_ holds a pointer of type MemoryChunk |
| 688 | base::AtomicWord prev_chunk_; |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 689 | |
| 690 | friend class MemoryAllocator; |
| 691 | }; |
| 692 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 693 | |
| 694 | STATIC_ASSERT(sizeof(MemoryChunk) <= MemoryChunk::kHeaderSize); |
| 695 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 696 | |
| 697 | // ----------------------------------------------------------------------------- |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 698 | // A page is a memory chunk of a size 1MB. Large object pages may be larger. |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 699 | // |
| 700 | // The only way to get a page pointer is by calling factory methods: |
| 701 | // Page* p = Page::FromAddress(addr); or |
| 702 | // Page* p = Page::FromAllocationTop(top); |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 703 | class Page : public MemoryChunk { |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 704 | public: |
| 705 | // Returns the page containing a given address. The address ranges |
| 706 | // from [page_addr .. page_addr + kPageSize[ |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 707 | // This only works if the object is in fact in a page. See also MemoryChunk:: |
| 708 | // FromAddress() and FromAnyAddress(). |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 709 | INLINE(static Page* FromAddress(Address a)) { |
| 710 | return reinterpret_cast<Page*>(OffsetFrom(a) & ~kPageAlignmentMask); |
| 711 | } |
| 712 | |
| 713 | // Returns the page containing an allocation top. Because an allocation |
| 714 | // top address can be the upper bound of the page, we need to subtract |
| 715 | // it with kPointerSize first. The address ranges from |
| 716 | // [page_addr + kObjectStartOffset .. page_addr + kPageSize]. |
| 717 | INLINE(static Page* FromAllocationTop(Address top)) { |
| 718 | Page* p = FromAddress(top - kPointerSize); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 719 | return p; |
| 720 | } |
| 721 | |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 722 | // Returns the next page in the chain of pages owned by a space. |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 723 | inline Page* next_page(); |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 724 | inline Page* prev_page(); |
| 725 | inline void set_next_page(Page* page); |
| 726 | inline void set_prev_page(Page* page); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 727 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 728 | // Checks whether an address is page aligned. |
| 729 | static bool IsAlignedToPageSize(Address a) { |
| 730 | return 0 == (OffsetFrom(a) & kPageAlignmentMask); |
| 731 | } |
| 732 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 733 | // Returns the offset of a given address to this page. |
| 734 | INLINE(int Offset(Address a)) { |
Steve Block | d0582a6 | 2009-12-15 09:54:21 +0000 | [diff] [blame] | 735 | int offset = static_cast<int>(a - address()); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 736 | return offset; |
| 737 | } |
| 738 | |
| 739 | // Returns the address for a given offset to the this page. |
| 740 | Address OffsetToAddress(int offset) { |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 741 | DCHECK_PAGE_OFFSET(offset); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 742 | return address() + offset; |
| 743 | } |
| 744 | |
| 745 | // --------------------------------------------------------------------- |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 746 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 747 | // Page size in bytes. This must be a multiple of the OS page size. |
| 748 | static const int kPageSize = 1 << kPageSizeBits; |
| 749 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 750 | // Maximum object size that fits in a page. Objects larger than that size |
| 751 | // are allocated in large object space and are never moved in memory. This |
| 752 | // also applies to new space allocation, since objects are never migrated |
| 753 | // from new space to large object space. Takes double alignment into account. |
| 754 | static const int kMaxRegularHeapObjectSize = kPageSize - kObjectStartOffset; |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 755 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 756 | // Page size mask. |
| 757 | static const intptr_t kPageAlignmentMask = (1 << kPageSizeBits) - 1; |
| 758 | |
Ben Murdoch | 7f4d5bd | 2010-06-15 11:15:29 +0100 | [diff] [blame] | 759 | inline void ClearGCFields(); |
| 760 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 761 | static inline Page* Initialize(Heap* heap, MemoryChunk* chunk, |
| 762 | Executability executable, PagedSpace* owner); |
Ben Murdoch | 7f4d5bd | 2010-06-15 11:15:29 +0100 | [diff] [blame] | 763 | |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 764 | void InitializeAsAnchor(PagedSpace* owner); |
Ben Murdoch | 7f4d5bd | 2010-06-15 11:15:29 +0100 | [diff] [blame] | 765 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 766 | bool WasSwept() { return IsFlagSet(WAS_SWEPT); } |
| 767 | void SetWasSwept() { SetFlag(WAS_SWEPT); } |
| 768 | void ClearWasSwept() { ClearFlag(WAS_SWEPT); } |
Ben Murdoch | 7f4d5bd | 2010-06-15 11:15:29 +0100 | [diff] [blame] | 769 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 770 | void ResetFreeListStatistics(); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 771 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 772 | #define FRAGMENTATION_STATS_ACCESSORS(type, name) \ |
| 773 | type name() { return name##_; } \ |
| 774 | void set_##name(type name) { name##_ = name; } \ |
| 775 | void add_##name(type name) { name##_ += name; } |
| 776 | |
| 777 | FRAGMENTATION_STATS_ACCESSORS(intptr_t, non_available_small_blocks) |
| 778 | FRAGMENTATION_STATS_ACCESSORS(intptr_t, available_in_small_free_list) |
| 779 | FRAGMENTATION_STATS_ACCESSORS(intptr_t, available_in_medium_free_list) |
| 780 | FRAGMENTATION_STATS_ACCESSORS(intptr_t, available_in_large_free_list) |
| 781 | FRAGMENTATION_STATS_ACCESSORS(intptr_t, available_in_huge_free_list) |
| 782 | |
| 783 | #undef FRAGMENTATION_STATS_ACCESSORS |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 784 | |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 785 | #ifdef DEBUG |
| 786 | void Print(); |
| 787 | #endif // DEBUG |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 788 | |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 789 | friend class MemoryAllocator; |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 790 | }; |
| 791 | |
| 792 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 793 | STATIC_ASSERT(sizeof(Page) <= MemoryChunk::kHeaderSize); |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 794 | |
| 795 | |
| 796 | class LargePage : public MemoryChunk { |
| 797 | public: |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 798 | HeapObject* GetObject() { return HeapObject::FromAddress(area_start()); } |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 799 | |
| 800 | inline LargePage* next_page() const { |
| 801 | return static_cast<LargePage*>(next_chunk()); |
| 802 | } |
| 803 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 804 | inline void set_next_page(LargePage* page) { set_next_chunk(page); } |
| 805 | |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 806 | private: |
| 807 | static inline LargePage* Initialize(Heap* heap, MemoryChunk* chunk); |
| 808 | |
| 809 | friend class MemoryAllocator; |
| 810 | }; |
| 811 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 812 | STATIC_ASSERT(sizeof(LargePage) <= MemoryChunk::kHeaderSize); |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 813 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 814 | // ---------------------------------------------------------------------------- |
| 815 | // Space is the abstract superclass for all allocation spaces. |
| 816 | class Space : public Malloced { |
| 817 | public: |
Steve Block | 44f0eee | 2011-05-26 01:26:41 +0100 | [diff] [blame] | 818 | Space(Heap* heap, AllocationSpace id, Executability executable) |
| 819 | : heap_(heap), id_(id), executable_(executable) {} |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 820 | |
| 821 | virtual ~Space() {} |
| 822 | |
Steve Block | 44f0eee | 2011-05-26 01:26:41 +0100 | [diff] [blame] | 823 | Heap* heap() const { return heap_; } |
| 824 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 825 | // Does the space need executable memory? |
| 826 | Executability executable() { return executable_; } |
| 827 | |
| 828 | // Identity used in error reporting. |
| 829 | AllocationSpace identity() { return id_; } |
| 830 | |
Shimeng (Simon) Wang | 8a31eba | 2010-12-06 19:01:33 -0800 | [diff] [blame] | 831 | // Returns allocated size. |
Ben Murdoch | f87a203 | 2010-10-22 12:50:53 +0100 | [diff] [blame] | 832 | virtual intptr_t Size() = 0; |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 833 | |
Shimeng (Simon) Wang | 8a31eba | 2010-12-06 19:01:33 -0800 | [diff] [blame] | 834 | // Returns size of objects. Can differ from the allocated size |
| 835 | // (e.g. see LargeObjectSpace). |
| 836 | virtual intptr_t SizeOfObjects() { return Size(); } |
| 837 | |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 838 | virtual int RoundSizeDownToObjectAlignment(int size) { |
| 839 | if (id_ == CODE_SPACE) { |
| 840 | return RoundDown(size, kCodeAlignment); |
| 841 | } else { |
| 842 | return RoundDown(size, kPointerSize); |
| 843 | } |
| 844 | } |
| 845 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 846 | #ifdef DEBUG |
| 847 | virtual void Print() = 0; |
| 848 | #endif |
| 849 | |
| 850 | private: |
Steve Block | 44f0eee | 2011-05-26 01:26:41 +0100 | [diff] [blame] | 851 | Heap* heap_; |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 852 | AllocationSpace id_; |
| 853 | Executability executable_; |
| 854 | }; |
| 855 | |
| 856 | |
| 857 | // ---------------------------------------------------------------------------- |
| 858 | // All heap objects containing executable code (code objects) must be allocated |
| 859 | // from a 2 GB range of memory, so that they can call each other using 32-bit |
| 860 | // displacements. This happens automatically on 32-bit platforms, where 32-bit |
| 861 | // displacements cover the entire 4GB virtual address space. On 64-bit |
| 862 | // platforms, we support this using the CodeRange object, which reserves and |
| 863 | // manages a range of virtual memory. |
Steve Block | 44f0eee | 2011-05-26 01:26:41 +0100 | [diff] [blame] | 864 | class CodeRange { |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 865 | public: |
Ben Murdoch | 69a99ed | 2011-11-30 16:03:39 +0000 | [diff] [blame] | 866 | explicit CodeRange(Isolate* isolate); |
| 867 | ~CodeRange() { TearDown(); } |
| 868 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 869 | // Reserves a range of virtual memory, but does not commit any of it. |
| 870 | // Can only be called once, at heap initialization time. |
| 871 | // Returns false on failure. |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 872 | bool SetUp(size_t requested_size); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 873 | |
| 874 | // Frees the range of virtual memory, and frees the data structures used to |
| 875 | // manage it. |
Steve Block | 44f0eee | 2011-05-26 01:26:41 +0100 | [diff] [blame] | 876 | void TearDown(); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 877 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 878 | bool valid() { return code_range_ != NULL; } |
| 879 | Address start() { |
| 880 | DCHECK(valid()); |
| 881 | return static_cast<Address>(code_range_->address()); |
| 882 | } |
Steve Block | 44f0eee | 2011-05-26 01:26:41 +0100 | [diff] [blame] | 883 | bool contains(Address address) { |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 884 | if (!valid()) return false; |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 885 | Address start = static_cast<Address>(code_range_->address()); |
| 886 | return start <= address && address < start + code_range_->size(); |
| 887 | } |
| 888 | |
| 889 | // Allocates a chunk of memory from the large-object portion of |
| 890 | // the code range. On platforms with no separate code range, should |
| 891 | // not be called. |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 892 | MUST_USE_RESULT Address AllocateRawMemory(const size_t requested_size, |
| 893 | const size_t commit_size, |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 894 | size_t* allocated); |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 895 | bool CommitRawMemory(Address start, size_t length); |
| 896 | bool UncommitRawMemory(Address start, size_t length); |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 897 | void FreeRawMemory(Address buf, size_t length); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 898 | |
| 899 | private: |
Ben Murdoch | 69a99ed | 2011-11-30 16:03:39 +0000 | [diff] [blame] | 900 | Isolate* isolate_; |
Steve Block | 44f0eee | 2011-05-26 01:26:41 +0100 | [diff] [blame] | 901 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 902 | // The reserved range of virtual memory that all code objects are put in. |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 903 | base::VirtualMemory* code_range_; |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 904 | // Plain old data class, just a struct plus a constructor. |
| 905 | class FreeBlock { |
| 906 | public: |
| 907 | FreeBlock(Address start_arg, size_t size_arg) |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 908 | : start(start_arg), size(size_arg) { |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 909 | DCHECK(IsAddressAligned(start, MemoryChunk::kAlignment)); |
| 910 | DCHECK(size >= static_cast<size_t>(Page::kPageSize)); |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 911 | } |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 912 | FreeBlock(void* start_arg, size_t size_arg) |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 913 | : start(static_cast<Address>(start_arg)), size(size_arg) { |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 914 | DCHECK(IsAddressAligned(start, MemoryChunk::kAlignment)); |
| 915 | DCHECK(size >= static_cast<size_t>(Page::kPageSize)); |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 916 | } |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 917 | |
| 918 | Address start; |
| 919 | size_t size; |
| 920 | }; |
| 921 | |
| 922 | // Freed blocks of memory are added to the free list. When the allocation |
| 923 | // list is exhausted, the free list is sorted and merged to make the new |
| 924 | // allocation list. |
Steve Block | 44f0eee | 2011-05-26 01:26:41 +0100 | [diff] [blame] | 925 | List<FreeBlock> free_list_; |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 926 | // Memory is allocated from the free blocks on the allocation list. |
| 927 | // The block at current_allocation_block_index_ is the current block. |
Steve Block | 44f0eee | 2011-05-26 01:26:41 +0100 | [diff] [blame] | 928 | List<FreeBlock> allocation_list_; |
| 929 | int current_allocation_block_index_; |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 930 | |
| 931 | // Finds a block on the allocation list that contains at least the |
| 932 | // requested amount of memory. If none is found, sorts and merges |
| 933 | // the existing free memory blocks, and searches again. |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 934 | // If none can be found, returns false. |
| 935 | bool GetNextAllocationBlock(size_t requested); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 936 | // Compares the start addresses of two free blocks. |
| 937 | static int CompareFreeBlockAddress(const FreeBlock* left, |
| 938 | const FreeBlock* right); |
Steve Block | 44f0eee | 2011-05-26 01:26:41 +0100 | [diff] [blame] | 939 | |
Steve Block | 44f0eee | 2011-05-26 01:26:41 +0100 | [diff] [blame] | 940 | DISALLOW_COPY_AND_ASSIGN(CodeRange); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 941 | }; |
| 942 | |
| 943 | |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 944 | class SkipList { |
| 945 | public: |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 946 | SkipList() { Clear(); } |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 947 | |
| 948 | void Clear() { |
| 949 | for (int idx = 0; idx < kSize; idx++) { |
| 950 | starts_[idx] = reinterpret_cast<Address>(-1); |
| 951 | } |
| 952 | } |
| 953 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 954 | Address StartFor(Address addr) { return starts_[RegionNumber(addr)]; } |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 955 | |
| 956 | void AddObject(Address addr, int size) { |
| 957 | int start_region = RegionNumber(addr); |
| 958 | int end_region = RegionNumber(addr + size - kPointerSize); |
| 959 | for (int idx = start_region; idx <= end_region; idx++) { |
| 960 | if (starts_[idx] > addr) starts_[idx] = addr; |
| 961 | } |
| 962 | } |
| 963 | |
| 964 | static inline int RegionNumber(Address addr) { |
| 965 | return (OffsetFrom(addr) & Page::kPageAlignmentMask) >> kRegionSizeLog2; |
| 966 | } |
| 967 | |
| 968 | static void Update(Address addr, int size) { |
| 969 | Page* page = Page::FromAddress(addr); |
| 970 | SkipList* list = page->skip_list(); |
| 971 | if (list == NULL) { |
| 972 | list = new SkipList(); |
| 973 | page->set_skip_list(list); |
| 974 | } |
| 975 | |
| 976 | list->AddObject(addr, size); |
| 977 | } |
| 978 | |
| 979 | private: |
| 980 | static const int kRegionSizeLog2 = 13; |
| 981 | static const int kRegionSize = 1 << kRegionSizeLog2; |
| 982 | static const int kSize = Page::kPageSize / kRegionSize; |
| 983 | |
| 984 | STATIC_ASSERT(Page::kPageSize % kRegionSize == 0); |
| 985 | |
| 986 | Address starts_[kSize]; |
| 987 | }; |
| 988 | |
| 989 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 990 | // ---------------------------------------------------------------------------- |
| 991 | // A space acquires chunks of memory from the operating system. The memory |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 992 | // allocator allocated and deallocates pages for the paged heap spaces and large |
| 993 | // pages for large object space. |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 994 | // |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 995 | // Each space has to manage it's own pages. |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 996 | // |
Steve Block | 44f0eee | 2011-05-26 01:26:41 +0100 | [diff] [blame] | 997 | class MemoryAllocator { |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 998 | public: |
Ben Murdoch | 69a99ed | 2011-11-30 16:03:39 +0000 | [diff] [blame] | 999 | explicit MemoryAllocator(Isolate* isolate); |
| 1000 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1001 | // Initializes its internal bookkeeping structures. |
Russell Brenner | 90bac25 | 2010-11-18 13:33:46 -0800 | [diff] [blame] | 1002 | // Max capacity of the total space and executable memory limit. |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1003 | bool SetUp(intptr_t max_capacity, intptr_t capacity_executable); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1004 | |
Steve Block | 44f0eee | 2011-05-26 01:26:41 +0100 | [diff] [blame] | 1005 | void TearDown(); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1006 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1007 | Page* AllocatePage(intptr_t size, PagedSpace* owner, |
| 1008 | Executability executable); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1009 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1010 | LargePage* AllocateLargePage(intptr_t object_size, Space* owner, |
| 1011 | Executability executable); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1012 | |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1013 | void Free(MemoryChunk* chunk); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1014 | |
| 1015 | // Returns the maximum available bytes of heaps. |
Steve Block | 44f0eee | 2011-05-26 01:26:41 +0100 | [diff] [blame] | 1016 | intptr_t Available() { return capacity_ < size_ ? 0 : capacity_ - size_; } |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1017 | |
| 1018 | // Returns allocated spaces in bytes. |
Steve Block | 44f0eee | 2011-05-26 01:26:41 +0100 | [diff] [blame] | 1019 | intptr_t Size() { return size_; } |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1020 | |
Russell Brenner | 90bac25 | 2010-11-18 13:33:46 -0800 | [diff] [blame] | 1021 | // Returns the maximum available executable bytes of heaps. |
Steve Block | 44f0eee | 2011-05-26 01:26:41 +0100 | [diff] [blame] | 1022 | intptr_t AvailableExecutable() { |
Russell Brenner | 90bac25 | 2010-11-18 13:33:46 -0800 | [diff] [blame] | 1023 | if (capacity_executable_ < size_executable_) return 0; |
| 1024 | return capacity_executable_ - size_executable_; |
| 1025 | } |
| 1026 | |
Steve Block | 791712a | 2010-08-27 10:21:07 +0100 | [diff] [blame] | 1027 | // Returns allocated executable spaces in bytes. |
Steve Block | 44f0eee | 2011-05-26 01:26:41 +0100 | [diff] [blame] | 1028 | intptr_t SizeExecutable() { return size_executable_; } |
Steve Block | 791712a | 2010-08-27 10:21:07 +0100 | [diff] [blame] | 1029 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1030 | // Returns maximum available bytes that the old space can have. |
Steve Block | 44f0eee | 2011-05-26 01:26:41 +0100 | [diff] [blame] | 1031 | intptr_t MaxAvailable() { |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1032 | return (Available() / Page::kPageSize) * Page::kMaxRegularHeapObjectSize; |
| 1033 | } |
| 1034 | |
| 1035 | // Returns an indication of whether a pointer is in a space that has |
| 1036 | // been allocated by this MemoryAllocator. |
| 1037 | V8_INLINE bool IsOutsideAllocatedSpace(const void* address) const { |
| 1038 | return address < lowest_ever_allocated_ || |
| 1039 | address >= highest_ever_allocated_; |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1040 | } |
| 1041 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1042 | #ifdef DEBUG |
| 1043 | // Reports statistic info of the space. |
Steve Block | 44f0eee | 2011-05-26 01:26:41 +0100 | [diff] [blame] | 1044 | void ReportStatistics(); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1045 | #endif |
| 1046 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1047 | // Returns a MemoryChunk in which the memory region from commit_area_size to |
| 1048 | // reserve_area_size of the chunk area is reserved but not committed, it |
| 1049 | // could be committed later by calling MemoryChunk::CommitArea. |
| 1050 | MemoryChunk* AllocateChunk(intptr_t reserve_area_size, |
| 1051 | intptr_t commit_area_size, |
| 1052 | Executability executable, Space* space); |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1053 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1054 | Address ReserveAlignedMemory(size_t requested, size_t alignment, |
| 1055 | base::VirtualMemory* controller); |
| 1056 | Address AllocateAlignedMemory(size_t reserve_size, size_t commit_size, |
| 1057 | size_t alignment, Executability executable, |
| 1058 | base::VirtualMemory* controller); |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1059 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1060 | bool CommitMemory(Address addr, size_t size, Executability executable); |
| 1061 | |
| 1062 | void FreeMemory(base::VirtualMemory* reservation, Executability executable); |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1063 | void FreeMemory(Address addr, size_t size, Executability executable); |
| 1064 | |
| 1065 | // Commit a contiguous block of memory from the initial chunk. Assumes that |
| 1066 | // the address is not NULL, the size is greater than zero, and that the |
| 1067 | // block is contained in the initial chunk. Returns true if it succeeded |
| 1068 | // and false otherwise. |
| 1069 | bool CommitBlock(Address start, size_t size, Executability executable); |
| 1070 | |
| 1071 | // Uncommit a contiguous block of memory [start..(start+size)[. |
| 1072 | // start is not NULL, the size is greater than zero, and the |
| 1073 | // block is contained in the initial chunk. Returns true if it succeeded |
| 1074 | // and false otherwise. |
| 1075 | bool UncommitBlock(Address start, size_t size); |
| 1076 | |
| 1077 | // Zaps a contiguous block of memory [start..(start+size)[ thus |
| 1078 | // filling it up with a recognizable non-NULL bit pattern. |
| 1079 | void ZapBlock(Address start, size_t size); |
| 1080 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1081 | void PerformAllocationCallback(ObjectSpace space, AllocationAction action, |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1082 | size_t size); |
| 1083 | |
| 1084 | void AddMemoryAllocationCallback(MemoryAllocationCallback callback, |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1085 | ObjectSpace space, AllocationAction action); |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1086 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1087 | void RemoveMemoryAllocationCallback(MemoryAllocationCallback callback); |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1088 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1089 | bool MemoryAllocationCallbackRegistered(MemoryAllocationCallback callback); |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1090 | |
| 1091 | static int CodePageGuardStartOffset(); |
| 1092 | |
| 1093 | static int CodePageGuardSize(); |
| 1094 | |
| 1095 | static int CodePageAreaStartOffset(); |
| 1096 | |
| 1097 | static int CodePageAreaEndOffset(); |
| 1098 | |
| 1099 | static int CodePageAreaSize() { |
| 1100 | return CodePageAreaEndOffset() - CodePageAreaStartOffset(); |
| 1101 | } |
| 1102 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1103 | MUST_USE_RESULT bool CommitExecutableMemory(base::VirtualMemory* vm, |
| 1104 | Address start, size_t commit_size, |
| 1105 | size_t reserved_size); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1106 | |
| 1107 | private: |
Ben Murdoch | 69a99ed | 2011-11-30 16:03:39 +0000 | [diff] [blame] | 1108 | Isolate* isolate_; |
| 1109 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1110 | // Maximum space size in bytes. |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1111 | size_t capacity_; |
Russell Brenner | 90bac25 | 2010-11-18 13:33:46 -0800 | [diff] [blame] | 1112 | // Maximum subset of capacity_ that can be executable |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1113 | size_t capacity_executable_; |
Ben Murdoch | b0fe162 | 2011-05-05 13:52:32 +0100 | [diff] [blame] | 1114 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1115 | // Allocated space size in bytes. |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1116 | size_t size_; |
Steve Block | 791712a | 2010-08-27 10:21:07 +0100 | [diff] [blame] | 1117 | // Allocated executable space size in bytes. |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1118 | size_t size_executable_; |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1119 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1120 | // We keep the lowest and highest addresses allocated as a quick way |
| 1121 | // of determining that pointers are outside the heap. The estimate is |
| 1122 | // conservative, i.e. not all addrsses in 'allocated' space are allocated |
| 1123 | // to our heap. The range is [lowest, highest[, inclusive on the low end |
| 1124 | // and exclusive on the high end. |
| 1125 | void* lowest_ever_allocated_; |
| 1126 | void* highest_ever_allocated_; |
| 1127 | |
Iain Merrick | 9ac36c9 | 2010-09-13 15:29:50 +0100 | [diff] [blame] | 1128 | struct MemoryAllocationCallbackRegistration { |
| 1129 | MemoryAllocationCallbackRegistration(MemoryAllocationCallback callback, |
| 1130 | ObjectSpace space, |
| 1131 | AllocationAction action) |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1132 | : callback(callback), space(space), action(action) {} |
Iain Merrick | 9ac36c9 | 2010-09-13 15:29:50 +0100 | [diff] [blame] | 1133 | MemoryAllocationCallback callback; |
| 1134 | ObjectSpace space; |
| 1135 | AllocationAction action; |
| 1136 | }; |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1137 | |
Iain Merrick | 9ac36c9 | 2010-09-13 15:29:50 +0100 | [diff] [blame] | 1138 | // A List of callback that are triggered when memory is allocated or free'd |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1139 | List<MemoryAllocationCallbackRegistration> memory_allocation_callbacks_; |
Iain Merrick | 9ac36c9 | 2010-09-13 15:29:50 +0100 | [diff] [blame] | 1140 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1141 | // Initializes pages in a chunk. Returns the first page address. |
| 1142 | // This function and GetChunkId() are provided for the mark-compact |
| 1143 | // collector to rebuild page headers in the from space, which is |
| 1144 | // used as a marking stack and its page headers are destroyed. |
Steve Block | 44f0eee | 2011-05-26 01:26:41 +0100 | [diff] [blame] | 1145 | Page* InitializePagesInChunk(int chunk_id, int pages_in_chunk, |
| 1146 | PagedSpace* owner); |
Steve Block | 6ded16b | 2010-05-10 14:33:55 +0100 | [diff] [blame] | 1147 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1148 | void UpdateAllocatedSpaceLimits(void* low, void* high) { |
| 1149 | lowest_ever_allocated_ = Min(lowest_ever_allocated_, low); |
| 1150 | highest_ever_allocated_ = Max(highest_ever_allocated_, high); |
| 1151 | } |
| 1152 | |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1153 | DISALLOW_IMPLICIT_CONSTRUCTORS(MemoryAllocator); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1154 | }; |
| 1155 | |
| 1156 | |
| 1157 | // ----------------------------------------------------------------------------- |
| 1158 | // Interface for heap object iterator to be implemented by all object space |
| 1159 | // object iterators. |
| 1160 | // |
Leon Clarke | d91b9f7 | 2010-01-27 17:25:45 +0000 | [diff] [blame] | 1161 | // NOTE: The space specific object iterators also implements the own next() |
| 1162 | // method which is used to avoid using virtual functions |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1163 | // iterating a specific space. |
| 1164 | |
| 1165 | class ObjectIterator : public Malloced { |
| 1166 | public: |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1167 | virtual ~ObjectIterator() {} |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1168 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1169 | virtual HeapObject* next_object() = 0; |
| 1170 | }; |
| 1171 | |
| 1172 | |
| 1173 | // ----------------------------------------------------------------------------- |
| 1174 | // Heap object iterator in new/old/map spaces. |
| 1175 | // |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1176 | // A HeapObjectIterator iterates objects from the bottom of the given space |
| 1177 | // to its top or from the bottom of the given page to its top. |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1178 | // |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1179 | // If objects are allocated in the page during iteration the iterator may |
| 1180 | // or may not iterate over those objects. The caller must create a new |
| 1181 | // iterator in order to be sure to visit these new objects. |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1182 | class HeapObjectIterator : public ObjectIterator { |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1183 | public: |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1184 | // Creates a new object iterator in a given space. |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1185 | // If the size function is not given, the iterator calls the default |
| 1186 | // Object::Size(). |
| 1187 | explicit HeapObjectIterator(PagedSpace* space); |
| 1188 | HeapObjectIterator(PagedSpace* space, HeapObjectCallback size_func); |
Kristian Monsen | 80d68ea | 2010-09-08 11:05:35 +0100 | [diff] [blame] | 1189 | HeapObjectIterator(Page* page, HeapObjectCallback size_func); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1190 | |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1191 | // Advance to the next object, skipping free spaces and other fillers and |
| 1192 | // skipping the special garbage section of which there is one per space. |
| 1193 | // Returns NULL when the iteration has ended. |
| 1194 | inline HeapObject* Next() { |
| 1195 | do { |
| 1196 | HeapObject* next_obj = FromCurrentPage(); |
| 1197 | if (next_obj != NULL) return next_obj; |
| 1198 | } while (AdvanceToNextPage()); |
| 1199 | return NULL; |
Leon Clarke | d91b9f7 | 2010-01-27 17:25:45 +0000 | [diff] [blame] | 1200 | } |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1201 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1202 | virtual HeapObject* next_object() { return Next(); } |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1203 | |
| 1204 | private: |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1205 | enum PageMode { kOnePageOnly, kAllPagesInSpace }; |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1206 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1207 | Address cur_addr_; // Current iteration point. |
| 1208 | Address cur_end_; // End iteration point. |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1209 | HeapObjectCallback size_func_; // Size function or NULL. |
| 1210 | PagedSpace* space_; |
| 1211 | PageMode page_mode_; |
Leon Clarke | d91b9f7 | 2010-01-27 17:25:45 +0000 | [diff] [blame] | 1212 | |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1213 | // Fast (inlined) path of next(). |
| 1214 | inline HeapObject* FromCurrentPage(); |
Leon Clarke | d91b9f7 | 2010-01-27 17:25:45 +0000 | [diff] [blame] | 1215 | |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1216 | // Slow path of next(), goes into the next page. Returns false if the |
| 1217 | // iteration has ended. |
| 1218 | bool AdvanceToNextPage(); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1219 | |
| 1220 | // Initializes fields. |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1221 | inline void Initialize(PagedSpace* owner, Address start, Address end, |
| 1222 | PageMode mode, HeapObjectCallback size_func); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1223 | }; |
| 1224 | |
| 1225 | |
| 1226 | // ----------------------------------------------------------------------------- |
| 1227 | // A PageIterator iterates the pages in a paged space. |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1228 | |
| 1229 | class PageIterator BASE_EMBEDDED { |
| 1230 | public: |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1231 | explicit inline PageIterator(PagedSpace* space); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1232 | |
| 1233 | inline bool has_next(); |
| 1234 | inline Page* next(); |
| 1235 | |
| 1236 | private: |
| 1237 | PagedSpace* space_; |
| 1238 | Page* prev_page_; // Previous page returned. |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1239 | // Next page that will be returned. Cached here so that we can use this |
| 1240 | // iterator for operations that deallocate pages. |
| 1241 | Page* next_page_; |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1242 | }; |
| 1243 | |
| 1244 | |
| 1245 | // ----------------------------------------------------------------------------- |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1246 | // A space has a circular list of pages. The next page can be accessed via |
| 1247 | // Page::next_page() call. |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1248 | |
| 1249 | // An abstraction of allocation and relocation pointers in a page-structured |
| 1250 | // space. |
| 1251 | class AllocationInfo { |
| 1252 | public: |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1253 | AllocationInfo() : top_(NULL), limit_(NULL) {} |
| 1254 | |
| 1255 | INLINE(void set_top(Address top)) { |
| 1256 | SLOW_DCHECK(top == NULL || |
| 1257 | (reinterpret_cast<intptr_t>(top) & HeapObjectTagMask()) == 0); |
| 1258 | top_ = top; |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1259 | } |
| 1260 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1261 | INLINE(Address top()) const { |
| 1262 | SLOW_DCHECK(top_ == NULL || |
| 1263 | (reinterpret_cast<intptr_t>(top_) & HeapObjectTagMask()) == 0); |
| 1264 | return top_; |
| 1265 | } |
| 1266 | |
| 1267 | Address* top_address() { return &top_; } |
| 1268 | |
| 1269 | INLINE(void set_limit(Address limit)) { |
| 1270 | SLOW_DCHECK(limit == NULL || |
| 1271 | (reinterpret_cast<intptr_t>(limit) & HeapObjectTagMask()) == 0); |
| 1272 | limit_ = limit; |
| 1273 | } |
| 1274 | |
| 1275 | INLINE(Address limit()) const { |
| 1276 | SLOW_DCHECK(limit_ == NULL || |
| 1277 | (reinterpret_cast<intptr_t>(limit_) & HeapObjectTagMask()) == |
| 1278 | 0); |
| 1279 | return limit_; |
| 1280 | } |
| 1281 | |
| 1282 | Address* limit_address() { return &limit_; } |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1283 | |
| 1284 | #ifdef DEBUG |
| 1285 | bool VerifyPagedAllocation() { |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1286 | return (Page::FromAllocationTop(top_) == Page::FromAllocationTop(limit_)) && |
| 1287 | (top_ <= limit_); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1288 | } |
| 1289 | #endif |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1290 | |
| 1291 | private: |
| 1292 | // Current allocation top. |
| 1293 | Address top_; |
| 1294 | // Current allocation limit. |
| 1295 | Address limit_; |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1296 | }; |
| 1297 | |
| 1298 | |
| 1299 | // An abstraction of the accounting statistics of a page-structured space. |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1300 | // The 'capacity' of a space is the number of object-area bytes (i.e., not |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1301 | // including page bookkeeping structures) currently in the space. The 'size' |
| 1302 | // of a space is the number of allocated bytes, the 'waste' in the space is |
| 1303 | // the number of bytes that are not allocated and not available to |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1304 | // allocation without reorganizing the space via a GC (e.g. small blocks due |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1305 | // to internal fragmentation, top of page areas in map space), and the bytes |
| 1306 | // 'available' is the number of unallocated bytes that are not waste. The |
| 1307 | // capacity is the sum of size, waste, and available. |
| 1308 | // |
| 1309 | // The stats are only set by functions that ensure they stay balanced. These |
| 1310 | // functions increase or decrease one of the non-capacity stats in |
| 1311 | // conjunction with capacity, or else they always balance increases and |
| 1312 | // decreases to the non-capacity stats. |
| 1313 | class AllocationStats BASE_EMBEDDED { |
| 1314 | public: |
| 1315 | AllocationStats() { Clear(); } |
| 1316 | |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1317 | // Zero out all the allocation statistics (i.e., no capacity). |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1318 | void Clear() { |
| 1319 | capacity_ = 0; |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1320 | max_capacity_ = 0; |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1321 | size_ = 0; |
| 1322 | waste_ = 0; |
| 1323 | } |
| 1324 | |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1325 | void ClearSizeWaste() { |
| 1326 | size_ = capacity_; |
| 1327 | waste_ = 0; |
| 1328 | } |
| 1329 | |
| 1330 | // Reset the allocation statistics (i.e., available = capacity with no |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1331 | // wasted or allocated bytes). |
| 1332 | void Reset() { |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1333 | size_ = 0; |
| 1334 | waste_ = 0; |
| 1335 | } |
| 1336 | |
| 1337 | // Accessors for the allocation statistics. |
Ben Murdoch | f87a203 | 2010-10-22 12:50:53 +0100 | [diff] [blame] | 1338 | intptr_t Capacity() { return capacity_; } |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1339 | intptr_t MaxCapacity() { return max_capacity_; } |
Ben Murdoch | f87a203 | 2010-10-22 12:50:53 +0100 | [diff] [blame] | 1340 | intptr_t Size() { return size_; } |
| 1341 | intptr_t Waste() { return waste_; } |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1342 | |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1343 | // Grow the space by adding available bytes. They are initially marked as |
| 1344 | // being in use (part of the size), but will normally be immediately freed, |
| 1345 | // putting them on the free list and removing them from size_. |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1346 | void ExpandSpace(int size_in_bytes) { |
| 1347 | capacity_ += size_in_bytes; |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1348 | size_ += size_in_bytes; |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1349 | if (capacity_ > max_capacity_) { |
| 1350 | max_capacity_ = capacity_; |
| 1351 | } |
| 1352 | DCHECK(size_ >= 0); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1353 | } |
| 1354 | |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1355 | // Shrink the space by removing available bytes. Since shrinking is done |
| 1356 | // during sweeping, bytes have been marked as being in use (part of the size) |
| 1357 | // and are hereby freed. |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1358 | void ShrinkSpace(int size_in_bytes) { |
| 1359 | capacity_ -= size_in_bytes; |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1360 | size_ -= size_in_bytes; |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1361 | DCHECK(size_ >= 0); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1362 | } |
| 1363 | |
| 1364 | // Allocate from available bytes (available -> size). |
Ben Murdoch | f87a203 | 2010-10-22 12:50:53 +0100 | [diff] [blame] | 1365 | void AllocateBytes(intptr_t size_in_bytes) { |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1366 | size_ += size_in_bytes; |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1367 | DCHECK(size_ >= 0); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1368 | } |
| 1369 | |
| 1370 | // Free allocated bytes, making them available (size -> available). |
Ben Murdoch | f87a203 | 2010-10-22 12:50:53 +0100 | [diff] [blame] | 1371 | void DeallocateBytes(intptr_t size_in_bytes) { |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1372 | size_ -= size_in_bytes; |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1373 | DCHECK(size_ >= 0); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1374 | } |
| 1375 | |
| 1376 | // Waste free bytes (available -> waste). |
| 1377 | void WasteBytes(int size_in_bytes) { |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1378 | DCHECK(size_in_bytes >= 0); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1379 | waste_ += size_in_bytes; |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1380 | } |
| 1381 | |
| 1382 | private: |
Ben Murdoch | f87a203 | 2010-10-22 12:50:53 +0100 | [diff] [blame] | 1383 | intptr_t capacity_; |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1384 | intptr_t max_capacity_; |
Ben Murdoch | f87a203 | 2010-10-22 12:50:53 +0100 | [diff] [blame] | 1385 | intptr_t size_; |
| 1386 | intptr_t waste_; |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1387 | }; |
| 1388 | |
| 1389 | |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1390 | // ----------------------------------------------------------------------------- |
| 1391 | // Free lists for old object spaces |
| 1392 | // |
| 1393 | // Free-list nodes are free blocks in the heap. They look like heap objects |
| 1394 | // (free-list node pointers have the heap object tag, and they have a map like |
| 1395 | // a heap object). They have a size and a next pointer. The next pointer is |
| 1396 | // the raw address of the next free list node (or NULL). |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1397 | class FreeListNode : public HeapObject { |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1398 | public: |
| 1399 | // Obtain a free-list node from a raw address. This is not a cast because |
| 1400 | // it does not check nor require that the first word at the address is a map |
| 1401 | // pointer. |
| 1402 | static FreeListNode* FromAddress(Address address) { |
| 1403 | return reinterpret_cast<FreeListNode*>(HeapObject::FromAddress(address)); |
| 1404 | } |
| 1405 | |
| 1406 | static inline bool IsFreeListNode(HeapObject* object); |
| 1407 | |
| 1408 | // Set the size in bytes, which can be read with HeapObject::Size(). This |
| 1409 | // function also writes a map to the first word of the block so that it |
| 1410 | // looks like a heap object to the garbage collector and heap iteration |
| 1411 | // functions. |
| 1412 | void set_size(Heap* heap, int size_in_bytes); |
| 1413 | |
| 1414 | // Accessors for the next field. |
| 1415 | inline FreeListNode* next(); |
| 1416 | inline FreeListNode** next_address(); |
| 1417 | inline void set_next(FreeListNode* next); |
| 1418 | |
| 1419 | inline void Zap(); |
| 1420 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1421 | static inline FreeListNode* cast(Object* object) { |
| 1422 | return reinterpret_cast<FreeListNode*>(object); |
| 1423 | } |
| 1424 | |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1425 | private: |
| 1426 | static const int kNextOffset = POINTER_SIZE_ALIGN(FreeSpace::kHeaderSize); |
| 1427 | |
| 1428 | DISALLOW_IMPLICIT_CONSTRUCTORS(FreeListNode); |
| 1429 | }; |
| 1430 | |
| 1431 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1432 | // The free list category holds a pointer to the top element and a pointer to |
| 1433 | // the end element of the linked list of free memory blocks. |
| 1434 | class FreeListCategory { |
| 1435 | public: |
| 1436 | FreeListCategory() : top_(0), end_(NULL), available_(0) {} |
| 1437 | |
| 1438 | intptr_t Concatenate(FreeListCategory* category); |
| 1439 | |
| 1440 | void Reset(); |
| 1441 | |
| 1442 | void Free(FreeListNode* node, int size_in_bytes); |
| 1443 | |
| 1444 | FreeListNode* PickNodeFromList(int* node_size); |
| 1445 | FreeListNode* PickNodeFromList(int size_in_bytes, int* node_size); |
| 1446 | |
| 1447 | intptr_t EvictFreeListItemsInList(Page* p); |
| 1448 | bool ContainsPageFreeListItemsInList(Page* p); |
| 1449 | |
| 1450 | void RepairFreeList(Heap* heap); |
| 1451 | |
| 1452 | FreeListNode* top() const { |
| 1453 | return reinterpret_cast<FreeListNode*>(base::NoBarrier_Load(&top_)); |
| 1454 | } |
| 1455 | |
| 1456 | void set_top(FreeListNode* top) { |
| 1457 | base::NoBarrier_Store(&top_, reinterpret_cast<base::AtomicWord>(top)); |
| 1458 | } |
| 1459 | |
| 1460 | FreeListNode** GetEndAddress() { return &end_; } |
| 1461 | FreeListNode* end() const { return end_; } |
| 1462 | void set_end(FreeListNode* end) { end_ = end; } |
| 1463 | |
| 1464 | int* GetAvailableAddress() { return &available_; } |
| 1465 | int available() const { return available_; } |
| 1466 | void set_available(int available) { available_ = available; } |
| 1467 | |
| 1468 | base::Mutex* mutex() { return &mutex_; } |
| 1469 | |
| 1470 | bool IsEmpty() { return top() == 0; } |
| 1471 | |
| 1472 | #ifdef DEBUG |
| 1473 | intptr_t SumFreeList(); |
| 1474 | int FreeListLength(); |
| 1475 | #endif |
| 1476 | |
| 1477 | private: |
| 1478 | // top_ points to the top FreeListNode* in the free list category. |
| 1479 | base::AtomicWord top_; |
| 1480 | FreeListNode* end_; |
| 1481 | base::Mutex mutex_; |
| 1482 | |
| 1483 | // Total available bytes in all blocks of this free list category. |
| 1484 | int available_; |
| 1485 | }; |
| 1486 | |
| 1487 | |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1488 | // The free list for the old space. The free list is organized in such a way |
| 1489 | // as to encourage objects allocated around the same time to be near each |
| 1490 | // other. The normal way to allocate is intended to be by bumping a 'top' |
| 1491 | // pointer until it hits a 'limit' pointer. When the limit is hit we need to |
| 1492 | // find a new space to allocate from. This is done with the free list, which |
| 1493 | // is divided up into rough categories to cut down on waste. Having finer |
| 1494 | // categories would scatter allocation more. |
| 1495 | |
| 1496 | // The old space free list is organized in categories. |
| 1497 | // 1-31 words: Such small free areas are discarded for efficiency reasons. |
| 1498 | // They can be reclaimed by the compactor. However the distance between top |
| 1499 | // and limit may be this small. |
| 1500 | // 32-255 words: There is a list of spaces this large. It is used for top and |
| 1501 | // limit when the object we need to allocate is 1-31 words in size. These |
| 1502 | // spaces are called small. |
| 1503 | // 256-2047 words: There is a list of spaces this large. It is used for top and |
| 1504 | // limit when the object we need to allocate is 32-255 words in size. These |
| 1505 | // spaces are called medium. |
| 1506 | // 1048-16383 words: There is a list of spaces this large. It is used for top |
| 1507 | // and limit when the object we need to allocate is 256-2047 words in size. |
| 1508 | // These spaces are call large. |
| 1509 | // At least 16384 words. This list is for objects of 2048 words or larger. |
| 1510 | // Empty pages are added to this list. These spaces are called huge. |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1511 | class FreeList { |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1512 | public: |
| 1513 | explicit FreeList(PagedSpace* owner); |
| 1514 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1515 | intptr_t Concatenate(FreeList* free_list); |
| 1516 | |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1517 | // Clear the free list. |
| 1518 | void Reset(); |
| 1519 | |
| 1520 | // Return the number of bytes available on the free list. |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1521 | intptr_t available() { |
| 1522 | return small_list_.available() + medium_list_.available() + |
| 1523 | large_list_.available() + huge_list_.available(); |
| 1524 | } |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1525 | |
| 1526 | // Place a node on the free list. The block of size 'size_in_bytes' |
| 1527 | // starting at 'start' is placed on the free list. The return value is the |
| 1528 | // number of bytes that have been lost due to internal fragmentation by |
| 1529 | // freeing the block. Bookkeeping information will be written to the block, |
| 1530 | // i.e., its contents will be destroyed. The start address should be word |
| 1531 | // aligned, and the size should be a non-zero multiple of the word size. |
| 1532 | int Free(Address start, int size_in_bytes); |
| 1533 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1534 | // This method returns how much memory can be allocated after freeing |
| 1535 | // maximum_freed memory. |
| 1536 | static inline int GuaranteedAllocatable(int maximum_freed) { |
| 1537 | if (maximum_freed < kSmallListMin) { |
| 1538 | return 0; |
| 1539 | } else if (maximum_freed <= kSmallListMax) { |
| 1540 | return kSmallAllocationMax; |
| 1541 | } else if (maximum_freed <= kMediumListMax) { |
| 1542 | return kMediumAllocationMax; |
| 1543 | } else if (maximum_freed <= kLargeListMax) { |
| 1544 | return kLargeAllocationMax; |
| 1545 | } |
| 1546 | return maximum_freed; |
| 1547 | } |
| 1548 | |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1549 | // Allocate a block of size 'size_in_bytes' from the free list. The block |
| 1550 | // is unitialized. A failure is returned if no block is available. The |
| 1551 | // number of bytes lost to fragmentation is returned in the output parameter |
| 1552 | // 'wasted_bytes'. The size should be a non-zero multiple of the word size. |
| 1553 | MUST_USE_RESULT HeapObject* Allocate(int size_in_bytes); |
| 1554 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1555 | bool IsEmpty() { |
| 1556 | return small_list_.IsEmpty() && medium_list_.IsEmpty() && |
| 1557 | large_list_.IsEmpty() && huge_list_.IsEmpty(); |
| 1558 | } |
| 1559 | |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1560 | #ifdef DEBUG |
| 1561 | void Zap(); |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1562 | intptr_t SumFreeLists(); |
| 1563 | bool IsVeryLong(); |
| 1564 | #endif |
| 1565 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1566 | // Used after booting the VM. |
| 1567 | void RepairLists(Heap* heap); |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1568 | |
| 1569 | intptr_t EvictFreeListItems(Page* p); |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1570 | bool ContainsPageFreeListItems(Page* p); |
| 1571 | |
| 1572 | FreeListCategory* small_list() { return &small_list_; } |
| 1573 | FreeListCategory* medium_list() { return &medium_list_; } |
| 1574 | FreeListCategory* large_list() { return &large_list_; } |
| 1575 | FreeListCategory* huge_list() { return &huge_list_; } |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1576 | |
| 1577 | private: |
| 1578 | // The size range of blocks, in bytes. |
| 1579 | static const int kMinBlockSize = 3 * kPointerSize; |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1580 | static const int kMaxBlockSize = Page::kMaxRegularHeapObjectSize; |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1581 | |
| 1582 | FreeListNode* FindNodeFor(int size_in_bytes, int* node_size); |
| 1583 | |
| 1584 | PagedSpace* owner_; |
| 1585 | Heap* heap_; |
| 1586 | |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1587 | static const int kSmallListMin = 0x20 * kPointerSize; |
| 1588 | static const int kSmallListMax = 0xff * kPointerSize; |
| 1589 | static const int kMediumListMax = 0x7ff * kPointerSize; |
| 1590 | static const int kLargeListMax = 0x3fff * kPointerSize; |
| 1591 | static const int kSmallAllocationMax = kSmallListMin - kPointerSize; |
| 1592 | static const int kMediumAllocationMax = kSmallListMax; |
| 1593 | static const int kLargeAllocationMax = kMediumListMax; |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1594 | FreeListCategory small_list_; |
| 1595 | FreeListCategory medium_list_; |
| 1596 | FreeListCategory large_list_; |
| 1597 | FreeListCategory huge_list_; |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1598 | |
| 1599 | DISALLOW_IMPLICIT_CONSTRUCTORS(FreeList); |
| 1600 | }; |
| 1601 | |
| 1602 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1603 | class AllocationResult { |
| 1604 | public: |
| 1605 | // Implicit constructor from Object*. |
| 1606 | AllocationResult(Object* object) // NOLINT |
| 1607 | : object_(object), |
| 1608 | retry_space_(INVALID_SPACE) {} |
| 1609 | |
| 1610 | AllocationResult() : object_(NULL), retry_space_(INVALID_SPACE) {} |
| 1611 | |
| 1612 | static inline AllocationResult Retry(AllocationSpace space = NEW_SPACE) { |
| 1613 | return AllocationResult(space); |
| 1614 | } |
| 1615 | |
| 1616 | inline bool IsRetry() { return retry_space_ != INVALID_SPACE; } |
| 1617 | |
| 1618 | template <typename T> |
| 1619 | bool To(T** obj) { |
| 1620 | if (IsRetry()) return false; |
| 1621 | *obj = T::cast(object_); |
| 1622 | return true; |
| 1623 | } |
| 1624 | |
| 1625 | Object* ToObjectChecked() { |
| 1626 | CHECK(!IsRetry()); |
| 1627 | return object_; |
| 1628 | } |
| 1629 | |
| 1630 | AllocationSpace RetrySpace() { |
| 1631 | DCHECK(IsRetry()); |
| 1632 | return retry_space_; |
| 1633 | } |
| 1634 | |
| 1635 | private: |
| 1636 | explicit AllocationResult(AllocationSpace space) |
| 1637 | : object_(NULL), retry_space_(space) {} |
| 1638 | |
| 1639 | Object* object_; |
| 1640 | AllocationSpace retry_space_; |
| 1641 | }; |
| 1642 | |
| 1643 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1644 | class PagedSpace : public Space { |
| 1645 | public: |
| 1646 | // Creates a space with a maximum capacity, and an id. |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1647 | PagedSpace(Heap* heap, intptr_t max_capacity, AllocationSpace id, |
Ben Murdoch | f87a203 | 2010-10-22 12:50:53 +0100 | [diff] [blame] | 1648 | Executability executable); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1649 | |
| 1650 | virtual ~PagedSpace() {} |
| 1651 | |
| 1652 | // Set up the space using the given address range of virtual memory (from |
| 1653 | // the memory allocator's initial chunk) if possible. If the block of |
| 1654 | // addresses is not big enough to contain a single page-aligned page, a |
| 1655 | // fresh chunk will be allocated. |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1656 | bool SetUp(); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1657 | |
| 1658 | // Returns true if the space has been successfully set up and not |
| 1659 | // subsequently torn down. |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1660 | bool HasBeenSetUp(); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1661 | |
| 1662 | // Cleans up the space, frees all pages in this space except those belonging |
| 1663 | // to the initial chunk, uncommits addresses in the initial chunk. |
| 1664 | void TearDown(); |
| 1665 | |
| 1666 | // Checks whether an object/address is in this space. |
| 1667 | inline bool Contains(Address a); |
| 1668 | bool Contains(HeapObject* o) { return Contains(o->address()); } |
| 1669 | |
| 1670 | // Given an address occupied by a live object, return that object if it is |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1671 | // in this space, or a Smi if it is not. The implementation iterates over |
| 1672 | // objects in the page containing the address, the cost is linear in the |
| 1673 | // number of objects in the page. It may be slow. |
| 1674 | Object* FindObject(Address addr); |
| 1675 | |
| 1676 | // During boot the free_space_map is created, and afterwards we may need |
| 1677 | // to write it into the free list nodes that were already created. |
| 1678 | void RepairFreeListsAfterBoot(); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1679 | |
Ben Murdoch | 85b7179 | 2012-04-11 18:30:58 +0100 | [diff] [blame] | 1680 | // Prepares for a mark-compact GC. |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1681 | void PrepareForMarkCompact(); |
Ben Murdoch | 85b7179 | 2012-04-11 18:30:58 +0100 | [diff] [blame] | 1682 | |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1683 | // Current capacity without growing (Size() + Available()). |
Ben Murdoch | f87a203 | 2010-10-22 12:50:53 +0100 | [diff] [blame] | 1684 | intptr_t Capacity() { return accounting_stats_.Capacity(); } |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1685 | |
Steve Block | 3ce2e20 | 2009-11-05 08:53:23 +0000 | [diff] [blame] | 1686 | // Total amount of memory committed for this space. For paged |
| 1687 | // spaces this equals the capacity. |
Ben Murdoch | f87a203 | 2010-10-22 12:50:53 +0100 | [diff] [blame] | 1688 | intptr_t CommittedMemory() { return Capacity(); } |
Steve Block | 3ce2e20 | 2009-11-05 08:53:23 +0000 | [diff] [blame] | 1689 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1690 | // The maximum amount of memory ever committed for this space. |
| 1691 | intptr_t MaximumCommittedMemory() { return accounting_stats_.MaxCapacity(); } |
| 1692 | |
| 1693 | // Approximate amount of physical memory committed for this space. |
| 1694 | size_t CommittedPhysicalMemory(); |
| 1695 | |
| 1696 | struct SizeStats { |
| 1697 | intptr_t Total() { |
| 1698 | return small_size_ + medium_size_ + large_size_ + huge_size_; |
| 1699 | } |
| 1700 | |
| 1701 | intptr_t small_size_; |
| 1702 | intptr_t medium_size_; |
| 1703 | intptr_t large_size_; |
| 1704 | intptr_t huge_size_; |
| 1705 | }; |
| 1706 | |
| 1707 | void ObtainFreeListStatistics(Page* p, SizeStats* sizes); |
| 1708 | void ResetFreeListStatistics(); |
| 1709 | |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1710 | // Sets the capacity, the available space and the wasted space to zero. |
| 1711 | // The stats are rebuilt during sweeping by adding each page to the |
| 1712 | // capacity and the size when it is encountered. As free spaces are |
| 1713 | // discovered during the sweeping they are subtracted from the size and added |
| 1714 | // to the available and wasted totals. |
| 1715 | void ClearStats() { |
| 1716 | accounting_stats_.ClearSizeWaste(); |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1717 | ResetFreeListStatistics(); |
| 1718 | } |
| 1719 | |
| 1720 | // Increases the number of available bytes of that space. |
| 1721 | void AddToAccountingStats(intptr_t bytes) { |
| 1722 | accounting_stats_.DeallocateBytes(bytes); |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1723 | } |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1724 | |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1725 | // Available bytes without growing. These are the bytes on the free list. |
| 1726 | // The bytes in the linear allocation area are not included in this total |
| 1727 | // because updating the stats would slow down allocation. New pages are |
| 1728 | // immediately added to the free list so they show up here. |
| 1729 | intptr_t Available() { return free_list_.available(); } |
| 1730 | |
| 1731 | // Allocated bytes in this space. Garbage bytes that were not found due to |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1732 | // concurrent sweeping are counted as being allocated! The bytes in the |
| 1733 | // current linear allocation area (between top and limit) are also counted |
| 1734 | // here. |
Ben Murdoch | f87a203 | 2010-10-22 12:50:53 +0100 | [diff] [blame] | 1735 | virtual intptr_t Size() { return accounting_stats_.Size(); } |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1736 | |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1737 | // As size, but the bytes in lazily swept pages are estimated and the bytes |
| 1738 | // in the current linear allocation area are not included. |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1739 | virtual intptr_t SizeOfObjects(); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1740 | |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1741 | // Wasted bytes in this space. These are just the bytes that were thrown away |
| 1742 | // due to being too small to use for allocation. They do not include the |
| 1743 | // free bytes that were not found at all due to lazy sweeping. |
| 1744 | virtual intptr_t Waste() { return accounting_stats_.Waste(); } |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1745 | |
| 1746 | // Returns the allocation pointer in this space. |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1747 | Address top() { return allocation_info_.top(); } |
| 1748 | Address limit() { return allocation_info_.limit(); } |
| 1749 | |
| 1750 | // The allocation top address. |
| 1751 | Address* allocation_top_address() { return allocation_info_.top_address(); } |
| 1752 | |
| 1753 | // The allocation limit address. |
| 1754 | Address* allocation_limit_address() { |
| 1755 | return allocation_info_.limit_address(); |
| 1756 | } |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1757 | |
| 1758 | // Allocate the requested number of bytes in the space if possible, return a |
| 1759 | // failure object if not. |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1760 | MUST_USE_RESULT inline AllocationResult AllocateRaw(int size_in_bytes); |
Leon Clarke | e46be81 | 2010-01-19 14:06:41 +0000 | [diff] [blame] | 1761 | |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1762 | // Give a block of memory to the space's free list. It might be added to |
| 1763 | // the free list or accounted as waste. |
| 1764 | // If add_to_freelist is false then just accounting stats are updated and |
| 1765 | // no attempt to add area to free list is made. |
| 1766 | int Free(Address start, int size_in_bytes) { |
| 1767 | int wasted = free_list_.Free(start, size_in_bytes); |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1768 | accounting_stats_.DeallocateBytes(size_in_bytes); |
| 1769 | accounting_stats_.WasteBytes(wasted); |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1770 | return size_in_bytes - wasted; |
| 1771 | } |
Kristian Monsen | 80d68ea | 2010-09-08 11:05:35 +0100 | [diff] [blame] | 1772 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1773 | void ResetFreeList() { free_list_.Reset(); } |
| 1774 | |
Steve Block | 6ded16b | 2010-05-10 14:33:55 +0100 | [diff] [blame] | 1775 | // Set space allocation info. |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1776 | void SetTopAndLimit(Address top, Address limit) { |
| 1777 | DCHECK(top == limit || |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1778 | Page::FromAddress(top) == Page::FromAddress(limit - 1)); |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1779 | MemoryChunk::UpdateHighWaterMark(allocation_info_.top()); |
| 1780 | allocation_info_.set_top(top); |
| 1781 | allocation_info_.set_limit(limit); |
Steve Block | 6ded16b | 2010-05-10 14:33:55 +0100 | [diff] [blame] | 1782 | } |
| 1783 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1784 | // Empty space allocation info, returning unused area to free list. |
| 1785 | void EmptyAllocationInfo() { |
| 1786 | // Mark the old linear allocation area with a free space map so it can be |
| 1787 | // skipped when scanning the heap. |
| 1788 | int old_linear_size = static_cast<int>(limit() - top()); |
| 1789 | Free(top(), old_linear_size); |
| 1790 | SetTopAndLimit(NULL, NULL); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1791 | } |
| 1792 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1793 | void Allocate(int bytes) { accounting_stats_.AllocateBytes(bytes); } |
| 1794 | |
| 1795 | void IncreaseCapacity(int size); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1796 | |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1797 | // Releases an unused page and shrinks the space. |
| 1798 | void ReleasePage(Page* page); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1799 | |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1800 | // The dummy page that anchors the linked list of pages. |
| 1801 | Page* anchor() { return &anchor_; } |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1802 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1803 | #ifdef VERIFY_HEAP |
| 1804 | // Verify integrity of this space. |
| 1805 | virtual void Verify(ObjectVisitor* visitor); |
| 1806 | |
| 1807 | // Overridden by subclasses to verify space-specific object |
| 1808 | // properties (e.g., only maps or free-list nodes are in map space). |
| 1809 | virtual void VerifyObject(HeapObject* obj) {} |
| 1810 | #endif |
| 1811 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1812 | #ifdef DEBUG |
| 1813 | // Print meta info and objects in this space. |
| 1814 | virtual void Print(); |
| 1815 | |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1816 | // Reports statistics for the space |
| 1817 | void ReportStatistics(); |
| 1818 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1819 | // Report code object related statistics |
| 1820 | void CollectCodeStatistics(); |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1821 | static void ReportCodeStatistics(Isolate* isolate); |
| 1822 | static void ResetCodeStatistics(Isolate* isolate); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1823 | #endif |
| 1824 | |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1825 | // Evacuation candidates are swept by evacuator. Needs to return a valid |
| 1826 | // result before _and_ after evacuation has finished. |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1827 | static bool ShouldBeSweptBySweeperThreads(Page* p) { |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1828 | return !p->IsEvacuationCandidate() && |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1829 | !p->IsFlagSet(Page::RESCAN_ON_EVACUATION) && !p->WasSwept(); |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1830 | } |
| 1831 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1832 | void IncrementUnsweptFreeBytes(intptr_t by) { unswept_free_bytes_ += by; } |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1833 | |
| 1834 | void IncreaseUnsweptFreeBytes(Page* p) { |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1835 | DCHECK(ShouldBeSweptBySweeperThreads(p)); |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1836 | unswept_free_bytes_ += (p->area_size() - p->LiveBytes()); |
| 1837 | } |
| 1838 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1839 | void DecrementUnsweptFreeBytes(intptr_t by) { unswept_free_bytes_ -= by; } |
| 1840 | |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1841 | void DecreaseUnsweptFreeBytes(Page* p) { |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1842 | DCHECK(ShouldBeSweptBySweeperThreads(p)); |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1843 | unswept_free_bytes_ -= (p->area_size() - p->LiveBytes()); |
| 1844 | } |
| 1845 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1846 | void ResetUnsweptFreeBytes() { unswept_free_bytes_ = 0; } |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1847 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1848 | // This function tries to steal size_in_bytes memory from the sweeper threads |
| 1849 | // free-lists. If it does not succeed stealing enough memory, it will wait |
| 1850 | // for the sweeper threads to finish sweeping. |
| 1851 | // It returns true when sweeping is completed and false otherwise. |
| 1852 | bool EnsureSweeperProgress(intptr_t size_in_bytes); |
| 1853 | |
| 1854 | void set_end_of_unswept_pages(Page* page) { end_of_unswept_pages_ = page; } |
| 1855 | |
| 1856 | Page* end_of_unswept_pages() { return end_of_unswept_pages_; } |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1857 | |
| 1858 | Page* FirstPage() { return anchor_.next_page(); } |
| 1859 | Page* LastPage() { return anchor_.prev_page(); } |
| 1860 | |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1861 | void EvictEvacuationCandidatesFromFreeLists(); |
| 1862 | |
| 1863 | bool CanExpand(); |
| 1864 | |
| 1865 | // Returns the number of total pages in this space. |
| 1866 | int CountTotalPages(); |
| 1867 | |
| 1868 | // Return size of allocatable area on a page in this space. |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1869 | inline int AreaSize() { return area_size_; } |
| 1870 | |
| 1871 | void CreateEmergencyMemory(); |
| 1872 | void FreeEmergencyMemory(); |
| 1873 | void UseEmergencyMemory(); |
| 1874 | |
| 1875 | bool HasEmergencyMemory() { return emergency_memory_ != NULL; } |
Kristian Monsen | 80d68ea | 2010-09-08 11:05:35 +0100 | [diff] [blame] | 1876 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1877 | protected: |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1878 | FreeList* free_list() { return &free_list_; } |
| 1879 | |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1880 | int area_size_; |
| 1881 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1882 | // Maximum capacity of this space. |
Ben Murdoch | f87a203 | 2010-10-22 12:50:53 +0100 | [diff] [blame] | 1883 | intptr_t max_capacity_; |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1884 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1885 | intptr_t SizeOfFirstPage(); |
| 1886 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1887 | // Accounting information for this space. |
| 1888 | AllocationStats accounting_stats_; |
| 1889 | |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1890 | // The dummy page that anchors the double linked list of pages. |
| 1891 | Page anchor_; |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1892 | |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1893 | // The space's free list. |
| 1894 | FreeList free_list_; |
Steve Block | 6ded16b | 2010-05-10 14:33:55 +0100 | [diff] [blame] | 1895 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1896 | // Normal allocation information. |
| 1897 | AllocationInfo allocation_info_; |
| 1898 | |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1899 | // The number of free bytes which could be reclaimed by advancing the |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1900 | // concurrent sweeper threads. |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1901 | intptr_t unswept_free_bytes_; |
Ben Murdoch | c7cc028 | 2012-03-05 14:35:55 +0000 | [diff] [blame] | 1902 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1903 | // The sweeper threads iterate over the list of pointer and data space pages |
| 1904 | // and sweep these pages concurrently. They will stop sweeping after the |
| 1905 | // end_of_unswept_pages_ page. |
| 1906 | Page* end_of_unswept_pages_; |
| 1907 | |
| 1908 | // Emergency memory is the memory of a full page for a given space, allocated |
| 1909 | // conservatively before evacuating a page. If compaction fails due to out |
| 1910 | // of memory error the emergency memory can be used to complete compaction. |
| 1911 | // If not used, the emergency memory is released after compaction. |
| 1912 | MemoryChunk* emergency_memory_; |
| 1913 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1914 | // Expands the space by allocating a fixed number of pages. Returns false if |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1915 | // it cannot allocate requested number of pages from OS, or if the hard heap |
| 1916 | // size limit has been hit. |
| 1917 | bool Expand(); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1918 | |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1919 | // Generic fast case allocation function that tries linear allocation at the |
| 1920 | // address denoted by top in allocation_info_. |
| 1921 | inline HeapObject* AllocateLinearly(int size_in_bytes); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1922 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1923 | // If sweeping is still in progress try to sweep unswept pages. If that is |
| 1924 | // not successful, wait for the sweeper threads and re-try free-list |
| 1925 | // allocation. |
| 1926 | MUST_USE_RESULT HeapObject* WaitForSweeperThreadsAndRetryAllocation( |
| 1927 | int size_in_bytes); |
| 1928 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1929 | // Slow path of AllocateRaw. This function is space-dependent. |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1930 | MUST_USE_RESULT HeapObject* SlowAllocateRaw(int size_in_bytes); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1931 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1932 | friend class PageIterator; |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1933 | friend class MarkCompactCollector; |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1934 | }; |
| 1935 | |
| 1936 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1937 | class NumberAndSizeInfo BASE_EMBEDDED { |
| 1938 | public: |
| 1939 | NumberAndSizeInfo() : number_(0), bytes_(0) {} |
| 1940 | |
| 1941 | int number() const { return number_; } |
| 1942 | void increment_number(int num) { number_ += num; } |
| 1943 | |
| 1944 | int bytes() const { return bytes_; } |
| 1945 | void increment_bytes(int size) { bytes_ += size; } |
| 1946 | |
| 1947 | void clear() { |
| 1948 | number_ = 0; |
| 1949 | bytes_ = 0; |
| 1950 | } |
| 1951 | |
| 1952 | private: |
| 1953 | int number_; |
| 1954 | int bytes_; |
| 1955 | }; |
| 1956 | |
| 1957 | |
| 1958 | // HistogramInfo class for recording a single "bar" of a histogram. This |
Ben Murdoch | 3fb3ca8 | 2011-12-02 17:19:32 +0000 | [diff] [blame] | 1959 | // class is used for collecting statistics to print to the log file. |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1960 | class HistogramInfo : public NumberAndSizeInfo { |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1961 | public: |
| 1962 | HistogramInfo() : NumberAndSizeInfo() {} |
| 1963 | |
| 1964 | const char* name() { return name_; } |
| 1965 | void set_name(const char* name) { name_ = name; } |
| 1966 | |
| 1967 | private: |
| 1968 | const char* name_; |
| 1969 | }; |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1970 | |
| 1971 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1972 | enum SemiSpaceId { kFromSpace = 0, kToSpace = 1 }; |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1973 | |
| 1974 | |
| 1975 | class SemiSpace; |
| 1976 | |
| 1977 | |
| 1978 | class NewSpacePage : public MemoryChunk { |
| 1979 | public: |
| 1980 | // GC related flags copied from from-space to to-space when |
| 1981 | // flipping semispaces. |
| 1982 | static const intptr_t kCopyOnFlipFlagsMask = |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1983 | (1 << MemoryChunk::POINTERS_TO_HERE_ARE_INTERESTING) | |
| 1984 | (1 << MemoryChunk::POINTERS_FROM_HERE_ARE_INTERESTING) | |
| 1985 | (1 << MemoryChunk::SCAN_ON_SCAVENGE); |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1986 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1987 | static const int kAreaSize = Page::kMaxRegularHeapObjectSize; |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1988 | |
| 1989 | inline NewSpacePage* next_page() const { |
| 1990 | return static_cast<NewSpacePage*>(next_chunk()); |
| 1991 | } |
| 1992 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1993 | inline void set_next_page(NewSpacePage* page) { set_next_chunk(page); } |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 1994 | |
| 1995 | inline NewSpacePage* prev_page() const { |
| 1996 | return static_cast<NewSpacePage*>(prev_chunk()); |
| 1997 | } |
| 1998 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 1999 | inline void set_prev_page(NewSpacePage* page) { set_prev_chunk(page); } |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2000 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2001 | SemiSpace* semi_space() { return reinterpret_cast<SemiSpace*>(owner()); } |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2002 | |
| 2003 | bool is_anchor() { return !this->InNewSpace(); } |
| 2004 | |
| 2005 | static bool IsAtStart(Address addr) { |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2006 | return (reinterpret_cast<intptr_t>(addr) & Page::kPageAlignmentMask) == |
| 2007 | kObjectStartOffset; |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2008 | } |
| 2009 | |
| 2010 | static bool IsAtEnd(Address addr) { |
| 2011 | return (reinterpret_cast<intptr_t>(addr) & Page::kPageAlignmentMask) == 0; |
| 2012 | } |
| 2013 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2014 | Address address() { return reinterpret_cast<Address>(this); } |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2015 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2016 | // Finds the NewSpacePage containing the given address. |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2017 | static inline NewSpacePage* FromAddress(Address address_in_page) { |
| 2018 | Address page_start = |
| 2019 | reinterpret_cast<Address>(reinterpret_cast<uintptr_t>(address_in_page) & |
| 2020 | ~Page::kPageAlignmentMask); |
| 2021 | NewSpacePage* page = reinterpret_cast<NewSpacePage*>(page_start); |
| 2022 | return page; |
| 2023 | } |
| 2024 | |
| 2025 | // Find the page for a limit address. A limit address is either an address |
| 2026 | // inside a page, or the address right after the last byte of a page. |
| 2027 | static inline NewSpacePage* FromLimit(Address address_limit) { |
| 2028 | return NewSpacePage::FromAddress(address_limit - 1); |
| 2029 | } |
| 2030 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2031 | // Checks if address1 and address2 are on the same new space page. |
| 2032 | static inline bool OnSamePage(Address address1, Address address2) { |
| 2033 | return NewSpacePage::FromAddress(address1) == |
| 2034 | NewSpacePage::FromAddress(address2); |
| 2035 | } |
| 2036 | |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2037 | private: |
| 2038 | // Create a NewSpacePage object that is only used as anchor |
| 2039 | // for the doubly-linked list of real pages. |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2040 | explicit NewSpacePage(SemiSpace* owner) { InitializeAsAnchor(owner); } |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2041 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2042 | static NewSpacePage* Initialize(Heap* heap, Address start, |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2043 | SemiSpace* semi_space); |
| 2044 | |
| 2045 | // Intialize a fake NewSpacePage used as sentinel at the ends |
| 2046 | // of a doubly-linked list of real NewSpacePages. |
| 2047 | // Only uses the prev/next links, and sets flags to not be in new-space. |
| 2048 | void InitializeAsAnchor(SemiSpace* owner); |
| 2049 | |
| 2050 | friend class SemiSpace; |
| 2051 | friend class SemiSpaceIterator; |
| 2052 | }; |
| 2053 | |
| 2054 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2055 | // ----------------------------------------------------------------------------- |
| 2056 | // SemiSpace in young generation |
| 2057 | // |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2058 | // A semispace is a contiguous chunk of memory holding page-like memory |
| 2059 | // chunks. The mark-compact collector uses the memory of the first page in |
| 2060 | // the from space as a marking stack when tracing live objects. |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2061 | |
| 2062 | class SemiSpace : public Space { |
| 2063 | public: |
| 2064 | // Constructor. |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2065 | SemiSpace(Heap* heap, SemiSpaceId semispace) |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2066 | : Space(heap, NEW_SPACE, NOT_EXECUTABLE), |
| 2067 | start_(NULL), |
| 2068 | age_mark_(NULL), |
| 2069 | id_(semispace), |
| 2070 | anchor_(this), |
| 2071 | current_page_(NULL) {} |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2072 | |
| 2073 | // Sets up the semispace using the given chunk. |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2074 | void SetUp(Address start, int initial_capacity, int maximum_capacity); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2075 | |
| 2076 | // Tear down the space. Heap memory was not allocated by the space, so it |
| 2077 | // is not deallocated here. |
| 2078 | void TearDown(); |
| 2079 | |
| 2080 | // True if the space has been set up but not torn down. |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2081 | bool HasBeenSetUp() { return start_ != NULL; } |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2082 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2083 | // Grow the semispace to the new capacity. The new capacity |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2084 | // requested must be larger than the current capacity and less than |
| 2085 | // the maximum capacity. |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2086 | bool GrowTo(int new_capacity); |
| 2087 | |
| 2088 | // Shrinks the semispace to the new capacity. The new capacity |
| 2089 | // requested must be more than the amount of used memory in the |
| 2090 | // semispace and less than the current capacity. |
| 2091 | bool ShrinkTo(int new_capacity); |
| 2092 | |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2093 | // Returns the start address of the first page of the space. |
| 2094 | Address space_start() { |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2095 | DCHECK(anchor_.next_page() != &anchor_); |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2096 | return anchor_.next_page()->area_start(); |
| 2097 | } |
| 2098 | |
| 2099 | // Returns the start address of the current page of the space. |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2100 | Address page_low() { return current_page_->area_start(); } |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2101 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2102 | // Returns one past the end address of the space. |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2103 | Address space_end() { return anchor_.prev_page()->area_end(); } |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2104 | |
| 2105 | // Returns one past the end address of the current page of the space. |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2106 | Address page_high() { return current_page_->area_end(); } |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2107 | |
| 2108 | bool AdvancePage() { |
| 2109 | NewSpacePage* next_page = current_page_->next_page(); |
| 2110 | if (next_page == anchor()) return false; |
| 2111 | current_page_ = next_page; |
| 2112 | return true; |
| 2113 | } |
| 2114 | |
| 2115 | // Resets the space to using the first page. |
| 2116 | void Reset(); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2117 | |
| 2118 | // Age mark accessors. |
| 2119 | Address age_mark() { return age_mark_; } |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2120 | void set_age_mark(Address mark); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2121 | |
| 2122 | // True if the address is in the address range of this semispace (not |
| 2123 | // necessarily below the allocation pointer). |
| 2124 | bool Contains(Address a) { |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2125 | return (reinterpret_cast<uintptr_t>(a) & address_mask_) == |
| 2126 | reinterpret_cast<uintptr_t>(start_); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2127 | } |
| 2128 | |
| 2129 | // True if the object is a heap object in the address range of this |
| 2130 | // semispace (not necessarily below the allocation pointer). |
| 2131 | bool Contains(Object* o) { |
| 2132 | return (reinterpret_cast<uintptr_t>(o) & object_mask_) == object_expected_; |
| 2133 | } |
| 2134 | |
Leon Clarke | e46be81 | 2010-01-19 14:06:41 +0000 | [diff] [blame] | 2135 | // If we don't have these here then SemiSpace will be abstract. However |
| 2136 | // they should never be called. |
Ben Murdoch | f87a203 | 2010-10-22 12:50:53 +0100 | [diff] [blame] | 2137 | virtual intptr_t Size() { |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2138 | UNREACHABLE(); |
| 2139 | return 0; |
| 2140 | } |
| 2141 | |
| 2142 | bool is_committed() { return committed_; } |
| 2143 | bool Commit(); |
| 2144 | bool Uncommit(); |
| 2145 | |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2146 | NewSpacePage* first_page() { return anchor_.next_page(); } |
| 2147 | NewSpacePage* current_page() { return current_page_; } |
| 2148 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2149 | #ifdef VERIFY_HEAP |
| 2150 | virtual void Verify(); |
| 2151 | #endif |
| 2152 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2153 | #ifdef DEBUG |
| 2154 | virtual void Print(); |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2155 | // Validate a range of of addresses in a SemiSpace. |
| 2156 | // The "from" address must be on a page prior to the "to" address, |
| 2157 | // in the linked page order, or it must be earlier on the same page. |
| 2158 | static void AssertValidRange(Address from, Address to); |
| 2159 | #else |
| 2160 | // Do nothing. |
| 2161 | inline static void AssertValidRange(Address from, Address to) {} |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2162 | #endif |
| 2163 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2164 | // Returns the current total capacity of the semispace. |
| 2165 | int TotalCapacity() { return total_capacity_; } |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2166 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2167 | // Returns the maximum total capacity of the semispace. |
| 2168 | int MaximumTotalCapacity() { return maximum_total_capacity_; } |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2169 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2170 | // Returns the initial capacity of the semispace. |
| 2171 | int InitialTotalCapacity() { return initial_total_capacity_; } |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2172 | |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2173 | SemiSpaceId id() { return id_; } |
| 2174 | |
| 2175 | static void Swap(SemiSpace* from, SemiSpace* to); |
| 2176 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2177 | // Returns the maximum amount of memory ever committed by the semi space. |
| 2178 | size_t MaximumCommittedMemory() { return maximum_committed_; } |
| 2179 | |
| 2180 | // Approximate amount of physical memory committed for this space. |
| 2181 | size_t CommittedPhysicalMemory(); |
| 2182 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2183 | private: |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2184 | // Flips the semispace between being from-space and to-space. |
| 2185 | // Copies the flags into the masked positions on all pages in the space. |
| 2186 | void FlipPages(intptr_t flags, intptr_t flag_mask); |
| 2187 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2188 | // Updates Capacity and MaximumCommitted based on new capacity. |
| 2189 | void SetCapacity(int new_capacity); |
| 2190 | |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2191 | NewSpacePage* anchor() { return &anchor_; } |
| 2192 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2193 | // The current and maximum total capacity of the space. |
| 2194 | int total_capacity_; |
| 2195 | int maximum_total_capacity_; |
| 2196 | int initial_total_capacity_; |
| 2197 | |
| 2198 | intptr_t maximum_committed_; |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2199 | |
| 2200 | // The start address of the space. |
| 2201 | Address start_; |
| 2202 | // Used to govern object promotion during mark-compact collection. |
| 2203 | Address age_mark_; |
| 2204 | |
| 2205 | // Masks and comparison values to test for containment in this semispace. |
| 2206 | uintptr_t address_mask_; |
| 2207 | uintptr_t object_mask_; |
| 2208 | uintptr_t object_expected_; |
| 2209 | |
| 2210 | bool committed_; |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2211 | SemiSpaceId id_; |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2212 | |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2213 | NewSpacePage anchor_; |
| 2214 | NewSpacePage* current_page_; |
| 2215 | |
| 2216 | friend class SemiSpaceIterator; |
| 2217 | friend class NewSpacePageIterator; |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2218 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2219 | public: |
| 2220 | TRACK_MEMORY("SemiSpace") |
| 2221 | }; |
| 2222 | |
| 2223 | |
| 2224 | // A SemiSpaceIterator is an ObjectIterator that iterates over the active |
| 2225 | // semispace of the heap's new space. It iterates over the objects in the |
| 2226 | // semispace from a given start address (defaulting to the bottom of the |
| 2227 | // semispace) to the top of the semispace. New objects allocated after the |
| 2228 | // iterator is created are not iterated. |
| 2229 | class SemiSpaceIterator : public ObjectIterator { |
| 2230 | public: |
| 2231 | // Create an iterator over the objects in the given space. If no start |
| 2232 | // address is given, the iterator starts from the bottom of the space. If |
| 2233 | // no size function is given, the iterator calls Object::Size(). |
Ben Murdoch | 592a9fc | 2012-03-05 11:04:45 +0000 | [diff] [blame] | 2234 | |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2235 | // Iterate over all of allocated to-space. |
| 2236 | explicit SemiSpaceIterator(NewSpace* space); |
| 2237 | // Iterate over all of allocated to-space, with a custome size function. |
| 2238 | SemiSpaceIterator(NewSpace* space, HeapObjectCallback size_func); |
| 2239 | // Iterate over part of allocated to-space, from start to the end |
| 2240 | // of allocation. |
| 2241 | SemiSpaceIterator(NewSpace* space, Address start); |
| 2242 | // Iterate from one address to another in the same semi-space. |
| 2243 | SemiSpaceIterator(Address from, Address to); |
| 2244 | |
| 2245 | HeapObject* Next() { |
Leon Clarke | d91b9f7 | 2010-01-27 17:25:45 +0000 | [diff] [blame] | 2246 | if (current_ == limit_) return NULL; |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2247 | if (NewSpacePage::IsAtEnd(current_)) { |
| 2248 | NewSpacePage* page = NewSpacePage::FromLimit(current_); |
| 2249 | page = page->next_page(); |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2250 | DCHECK(!page->is_anchor()); |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2251 | current_ = page->area_start(); |
| 2252 | if (current_ == limit_) return NULL; |
| 2253 | } |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2254 | |
| 2255 | HeapObject* object = HeapObject::FromAddress(current_); |
| 2256 | int size = (size_func_ == NULL) ? object->Size() : size_func_(object); |
| 2257 | |
| 2258 | current_ += size; |
| 2259 | return object; |
| 2260 | } |
| 2261 | |
| 2262 | // Implementation of the ObjectIterator functions. |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2263 | virtual HeapObject* next_object() { return Next(); } |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2264 | |
| 2265 | private: |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2266 | void Initialize(Address start, Address end, HeapObjectCallback size_func); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2267 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2268 | // The current iteration point. |
| 2269 | Address current_; |
| 2270 | // The end of iteration. |
| 2271 | Address limit_; |
| 2272 | // The callback function. |
| 2273 | HeapObjectCallback size_func_; |
| 2274 | }; |
| 2275 | |
| 2276 | |
| 2277 | // ----------------------------------------------------------------------------- |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2278 | // A PageIterator iterates the pages in a semi-space. |
| 2279 | class NewSpacePageIterator BASE_EMBEDDED { |
| 2280 | public: |
| 2281 | // Make an iterator that runs over all pages in to-space. |
| 2282 | explicit inline NewSpacePageIterator(NewSpace* space); |
| 2283 | |
| 2284 | // Make an iterator that runs over all pages in the given semispace, |
| 2285 | // even those not used in allocation. |
| 2286 | explicit inline NewSpacePageIterator(SemiSpace* space); |
| 2287 | |
| 2288 | // Make iterator that iterates from the page containing start |
| 2289 | // to the page that contains limit in the same semispace. |
| 2290 | inline NewSpacePageIterator(Address start, Address limit); |
| 2291 | |
| 2292 | inline bool has_next(); |
| 2293 | inline NewSpacePage* next(); |
| 2294 | |
| 2295 | private: |
| 2296 | NewSpacePage* prev_page_; // Previous page returned. |
| 2297 | // Next page that will be returned. Cached here so that we can use this |
| 2298 | // iterator for operations that deallocate pages. |
| 2299 | NewSpacePage* next_page_; |
| 2300 | // Last page returned. |
| 2301 | NewSpacePage* last_page_; |
| 2302 | }; |
| 2303 | |
| 2304 | |
| 2305 | // ----------------------------------------------------------------------------- |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2306 | // The young generation space. |
| 2307 | // |
| 2308 | // The new space consists of a contiguous pair of semispaces. It simply |
| 2309 | // forwards most functions to the appropriate semispace. |
| 2310 | |
| 2311 | class NewSpace : public Space { |
| 2312 | public: |
| 2313 | // Constructor. |
Steve Block | 44f0eee | 2011-05-26 01:26:41 +0100 | [diff] [blame] | 2314 | explicit NewSpace(Heap* heap) |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2315 | : Space(heap, NEW_SPACE, NOT_EXECUTABLE), |
| 2316 | to_space_(heap, kToSpace), |
| 2317 | from_space_(heap, kFromSpace), |
| 2318 | reservation_(), |
| 2319 | inline_allocation_limit_step_(0) {} |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2320 | |
| 2321 | // Sets up the new space using the given chunk. |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2322 | bool SetUp(int reserved_semispace_size_, int max_semi_space_size); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2323 | |
| 2324 | // Tears down the space. Heap memory was not allocated by the space, so it |
| 2325 | // is not deallocated here. |
| 2326 | void TearDown(); |
| 2327 | |
| 2328 | // True if the space has been set up but not torn down. |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2329 | bool HasBeenSetUp() { |
| 2330 | return to_space_.HasBeenSetUp() && from_space_.HasBeenSetUp(); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2331 | } |
| 2332 | |
| 2333 | // Flip the pair of spaces. |
| 2334 | void Flip(); |
| 2335 | |
| 2336 | // Grow the capacity of the semispaces. Assumes that they are not at |
| 2337 | // their maximum capacity. |
| 2338 | void Grow(); |
| 2339 | |
| 2340 | // Shrink the capacity of the semispaces. |
| 2341 | void Shrink(); |
| 2342 | |
| 2343 | // True if the address or object lies in the address range of either |
| 2344 | // semispace (not necessarily below the allocation pointer). |
| 2345 | bool Contains(Address a) { |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2346 | return (reinterpret_cast<uintptr_t>(a) & address_mask_) == |
| 2347 | reinterpret_cast<uintptr_t>(start_); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2348 | } |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2349 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2350 | bool Contains(Object* o) { |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2351 | Address a = reinterpret_cast<Address>(o); |
| 2352 | return (reinterpret_cast<uintptr_t>(a) & object_mask_) == object_expected_; |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2353 | } |
| 2354 | |
| 2355 | // Return the allocated bytes in the active semispace. |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2356 | virtual intptr_t Size() { |
| 2357 | return pages_used_ * NewSpacePage::kAreaSize + |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2358 | static_cast<int>(top() - to_space_.page_low()); |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2359 | } |
| 2360 | |
Ben Murdoch | f87a203 | 2010-10-22 12:50:53 +0100 | [diff] [blame] | 2361 | // The same, but returning an int. We have to have the one that returns |
| 2362 | // intptr_t because it is inherited, but if we know we are dealing with the |
| 2363 | // new space, which can't get as big as the other spaces then this is useful: |
| 2364 | int SizeAsInt() { return static_cast<int>(Size()); } |
Steve Block | 3ce2e20 | 2009-11-05 08:53:23 +0000 | [diff] [blame] | 2365 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2366 | // Return the allocatable capacity of a semispace. |
| 2367 | intptr_t Capacity() { |
| 2368 | SLOW_DCHECK(to_space_.TotalCapacity() == from_space_.TotalCapacity()); |
| 2369 | return (to_space_.TotalCapacity() / Page::kPageSize) * |
| 2370 | NewSpacePage::kAreaSize; |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2371 | } |
| 2372 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2373 | // Return the current size of a semispace, allocatable and non-allocatable |
| 2374 | // memory. |
| 2375 | intptr_t TotalCapacity() { |
| 2376 | DCHECK(to_space_.TotalCapacity() == from_space_.TotalCapacity()); |
| 2377 | return to_space_.TotalCapacity(); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2378 | } |
Steve Block | 3ce2e20 | 2009-11-05 08:53:23 +0000 | [diff] [blame] | 2379 | |
| 2380 | // Return the total amount of memory committed for new space. |
Ben Murdoch | f87a203 | 2010-10-22 12:50:53 +0100 | [diff] [blame] | 2381 | intptr_t CommittedMemory() { |
Steve Block | 3ce2e20 | 2009-11-05 08:53:23 +0000 | [diff] [blame] | 2382 | if (from_space_.is_committed()) return 2 * Capacity(); |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2383 | return TotalCapacity(); |
Steve Block | 3ce2e20 | 2009-11-05 08:53:23 +0000 | [diff] [blame] | 2384 | } |
| 2385 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2386 | // Return the total amount of memory committed for new space. |
| 2387 | intptr_t MaximumCommittedMemory() { |
| 2388 | return to_space_.MaximumCommittedMemory() + |
| 2389 | from_space_.MaximumCommittedMemory(); |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2390 | } |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2391 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2392 | // Approximate amount of physical memory committed for this space. |
| 2393 | size_t CommittedPhysicalMemory(); |
| 2394 | |
| 2395 | // Return the available bytes without growing. |
| 2396 | intptr_t Available() { return Capacity() - Size(); } |
| 2397 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2398 | // Return the maximum capacity of a semispace. |
| 2399 | int MaximumCapacity() { |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2400 | DCHECK(to_space_.MaximumTotalCapacity() == |
| 2401 | from_space_.MaximumTotalCapacity()); |
| 2402 | return to_space_.MaximumTotalCapacity(); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2403 | } |
| 2404 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2405 | bool IsAtMaximumCapacity() { return TotalCapacity() == MaximumCapacity(); } |
| 2406 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2407 | // Returns the initial capacity of a semispace. |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2408 | int InitialTotalCapacity() { |
| 2409 | DCHECK(to_space_.InitialTotalCapacity() == |
| 2410 | from_space_.InitialTotalCapacity()); |
| 2411 | return to_space_.InitialTotalCapacity(); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2412 | } |
| 2413 | |
| 2414 | // Return the address of the allocation pointer in the active semispace. |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2415 | Address top() { |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2416 | DCHECK(to_space_.current_page()->ContainsLimit(allocation_info_.top())); |
| 2417 | return allocation_info_.top(); |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2418 | } |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2419 | |
| 2420 | void set_top(Address top) { |
| 2421 | DCHECK(to_space_.current_page()->ContainsLimit(top)); |
| 2422 | allocation_info_.set_top(top); |
| 2423 | } |
| 2424 | |
| 2425 | // Return the address of the allocation pointer limit in the active semispace. |
| 2426 | Address limit() { |
| 2427 | DCHECK(to_space_.current_page()->ContainsLimit(allocation_info_.limit())); |
| 2428 | return allocation_info_.limit(); |
| 2429 | } |
| 2430 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2431 | // Return the address of the first object in the active semispace. |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2432 | Address bottom() { return to_space_.space_start(); } |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2433 | |
| 2434 | // Get the age mark of the inactive semispace. |
| 2435 | Address age_mark() { return from_space_.age_mark(); } |
| 2436 | // Set the age mark in the active semispace. |
| 2437 | void set_age_mark(Address mark) { to_space_.set_age_mark(mark); } |
| 2438 | |
| 2439 | // The start address of the space and a bit mask. Anding an address in the |
| 2440 | // new space with the mask will result in the start address. |
| 2441 | Address start() { return start_; } |
| 2442 | uintptr_t mask() { return address_mask_; } |
| 2443 | |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2444 | INLINE(uint32_t AddressToMarkbitIndex(Address addr)) { |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2445 | DCHECK(Contains(addr)); |
| 2446 | DCHECK(IsAligned(OffsetFrom(addr), kPointerSize) || |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2447 | IsAligned(OffsetFrom(addr) - 1, kPointerSize)); |
| 2448 | return static_cast<uint32_t>(addr - start_) >> kPointerSizeLog2; |
| 2449 | } |
| 2450 | |
| 2451 | INLINE(Address MarkbitIndexToAddress(uint32_t index)) { |
| 2452 | return reinterpret_cast<Address>(index << kPointerSizeLog2); |
| 2453 | } |
| 2454 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2455 | // The allocation top and limit address. |
| 2456 | Address* allocation_top_address() { return allocation_info_.top_address(); } |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2457 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2458 | // The allocation limit address. |
| 2459 | Address* allocation_limit_address() { |
| 2460 | return allocation_info_.limit_address(); |
| 2461 | } |
| 2462 | |
| 2463 | MUST_USE_RESULT INLINE(AllocationResult AllocateRaw(int size_in_bytes)); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2464 | |
| 2465 | // Reset the allocation pointer to the beginning of the active semispace. |
| 2466 | void ResetAllocationInfo(); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2467 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2468 | void UpdateInlineAllocationLimit(int size_in_bytes); |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2469 | void LowerInlineAllocationLimit(intptr_t step) { |
| 2470 | inline_allocation_limit_step_ = step; |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2471 | UpdateInlineAllocationLimit(0); |
| 2472 | top_on_previous_step_ = allocation_info_.top(); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2473 | } |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2474 | |
| 2475 | // Get the extent of the inactive semispace (for use as a marking stack, |
| 2476 | // or to zap it). Notice: space-addresses are not necessarily on the |
| 2477 | // same page, so FromSpaceStart() might be above FromSpaceEnd(). |
| 2478 | Address FromSpacePageLow() { return from_space_.page_low(); } |
| 2479 | Address FromSpacePageHigh() { return from_space_.page_high(); } |
| 2480 | Address FromSpaceStart() { return from_space_.space_start(); } |
| 2481 | Address FromSpaceEnd() { return from_space_.space_end(); } |
| 2482 | |
| 2483 | // Get the extent of the active semispace's pages' memory. |
| 2484 | Address ToSpaceStart() { return to_space_.space_start(); } |
| 2485 | Address ToSpaceEnd() { return to_space_.space_end(); } |
| 2486 | |
| 2487 | inline bool ToSpaceContains(Address address) { |
| 2488 | return to_space_.Contains(address); |
| 2489 | } |
| 2490 | inline bool FromSpaceContains(Address address) { |
| 2491 | return from_space_.Contains(address); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2492 | } |
| 2493 | |
| 2494 | // True if the object is a heap object in the address range of the |
| 2495 | // respective semispace (not necessarily below the allocation pointer of the |
| 2496 | // semispace). |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2497 | inline bool ToSpaceContains(Object* o) { return to_space_.Contains(o); } |
| 2498 | inline bool FromSpaceContains(Object* o) { return from_space_.Contains(o); } |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2499 | |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2500 | // Try to switch the active semispace to a new, empty, page. |
| 2501 | // Returns false if this isn't possible or reasonable (i.e., there |
| 2502 | // are no pages, or the current page is already empty), or true |
| 2503 | // if successful. |
| 2504 | bool AddFreshPage(); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2505 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2506 | #ifdef VERIFY_HEAP |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2507 | // Verify the active semispace. |
| 2508 | virtual void Verify(); |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2509 | #endif |
| 2510 | |
| 2511 | #ifdef DEBUG |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2512 | // Print the active semispace. |
| 2513 | virtual void Print() { to_space_.Print(); } |
| 2514 | #endif |
| 2515 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2516 | // Iterates the active semispace to collect statistics. |
| 2517 | void CollectStatistics(); |
| 2518 | // Reports previously collected statistics of the active semispace. |
| 2519 | void ReportStatistics(); |
| 2520 | // Clears previously collected statistics. |
| 2521 | void ClearHistograms(); |
| 2522 | |
| 2523 | // Record the allocation or promotion of a heap object. Note that we don't |
| 2524 | // record every single allocation, but only those that happen in the |
| 2525 | // to space during a scavenge GC. |
| 2526 | void RecordAllocation(HeapObject* obj); |
| 2527 | void RecordPromotion(HeapObject* obj); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2528 | |
| 2529 | // Return whether the operation succeded. |
| 2530 | bool CommitFromSpaceIfNeeded() { |
| 2531 | if (from_space_.is_committed()) return true; |
| 2532 | return from_space_.Commit(); |
| 2533 | } |
| 2534 | |
| 2535 | bool UncommitFromSpace() { |
| 2536 | if (!from_space_.is_committed()) return true; |
| 2537 | return from_space_.Uncommit(); |
| 2538 | } |
| 2539 | |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2540 | inline intptr_t inline_allocation_limit_step() { |
| 2541 | return inline_allocation_limit_step_; |
| 2542 | } |
| 2543 | |
| 2544 | SemiSpace* active_space() { return &to_space_; } |
| 2545 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2546 | private: |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2547 | // Update allocation info to match the current to-space page. |
| 2548 | void UpdateAllocationInfo(); |
| 2549 | |
| 2550 | Address chunk_base_; |
| 2551 | uintptr_t chunk_size_; |
| 2552 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2553 | // The semispaces. |
| 2554 | SemiSpace to_space_; |
| 2555 | SemiSpace from_space_; |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2556 | base::VirtualMemory reservation_; |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2557 | int pages_used_; |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2558 | |
| 2559 | // Start address and bit mask for containment testing. |
| 2560 | Address start_; |
| 2561 | uintptr_t address_mask_; |
| 2562 | uintptr_t object_mask_; |
| 2563 | uintptr_t object_expected_; |
| 2564 | |
| 2565 | // Allocation pointer and limit for normal allocation and allocation during |
| 2566 | // mark-compact collection. |
| 2567 | AllocationInfo allocation_info_; |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2568 | |
| 2569 | // When incremental marking is active we will set allocation_info_.limit |
| 2570 | // to be lower than actual limit and then will gradually increase it |
| 2571 | // in steps to guarantee that we do incremental marking steps even |
| 2572 | // when all allocation is performed from inlined generated code. |
| 2573 | intptr_t inline_allocation_limit_step_; |
| 2574 | |
| 2575 | Address top_on_previous_step_; |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2576 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2577 | HistogramInfo* allocated_histogram_; |
| 2578 | HistogramInfo* promoted_histogram_; |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2579 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2580 | MUST_USE_RESULT AllocationResult SlowAllocateRaw(int size_in_bytes); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2581 | |
| 2582 | friend class SemiSpaceIterator; |
| 2583 | |
| 2584 | public: |
| 2585 | TRACK_MEMORY("NewSpace") |
| 2586 | }; |
| 2587 | |
| 2588 | |
| 2589 | // ----------------------------------------------------------------------------- |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2590 | // Old object space (excluding map objects) |
| 2591 | |
| 2592 | class OldSpace : public PagedSpace { |
| 2593 | public: |
| 2594 | // Creates an old space object with a given maximum capacity. |
| 2595 | // The constructor does not allocate pages from OS. |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2596 | OldSpace(Heap* heap, intptr_t max_capacity, AllocationSpace id, |
Steve Block | 44f0eee | 2011-05-26 01:26:41 +0100 | [diff] [blame] | 2597 | Executability executable) |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2598 | : PagedSpace(heap, max_capacity, id, executable) {} |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2599 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2600 | public: |
| 2601 | TRACK_MEMORY("OldSpace") |
| 2602 | }; |
| 2603 | |
| 2604 | |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2605 | // For contiguous spaces, top should be in the space (or at the end) and limit |
| 2606 | // should be the end of the space. |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2607 | #define DCHECK_SEMISPACE_ALLOCATION_INFO(info, space) \ |
| 2608 | SLOW_DCHECK((space).page_low() <= (info).top() && \ |
| 2609 | (info).top() <= (space).page_high() && \ |
| 2610 | (info).limit() <= (space).page_high()) |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2611 | |
| 2612 | |
| 2613 | // ----------------------------------------------------------------------------- |
| 2614 | // Old space for all map objects |
| 2615 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2616 | class MapSpace : public PagedSpace { |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2617 | public: |
| 2618 | // Creates a map space object with a maximum capacity. |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2619 | MapSpace(Heap* heap, intptr_t max_capacity, AllocationSpace id) |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2620 | : PagedSpace(heap, max_capacity, id, NOT_EXECUTABLE), |
| 2621 | max_map_space_pages_(kMaxMapPageIndex - 1) {} |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2622 | |
Ben Murdoch | 85b7179 | 2012-04-11 18:30:58 +0100 | [diff] [blame] | 2623 | // Given an index, returns the page address. |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2624 | // TODO(1600): this limit is artifical just to keep code compilable |
| 2625 | static const int kMaxMapPageIndex = 1 << 16; |
Ben Murdoch | 85b7179 | 2012-04-11 18:30:58 +0100 | [diff] [blame] | 2626 | |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2627 | virtual int RoundSizeDownToObjectAlignment(int size) { |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2628 | if (base::bits::IsPowerOfTwo32(Map::kSize)) { |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2629 | return RoundDown(size, Map::kSize); |
| 2630 | } else { |
| 2631 | return (size / Map::kSize) * Map::kSize; |
Leon Clarke | e46be81 | 2010-01-19 14:06:41 +0000 | [diff] [blame] | 2632 | } |
Leon Clarke | e46be81 | 2010-01-19 14:06:41 +0000 | [diff] [blame] | 2633 | } |
| 2634 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2635 | protected: |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2636 | virtual void VerifyObject(HeapObject* obj); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2637 | |
| 2638 | private: |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2639 | static const int kMapsPerPage = Page::kMaxRegularHeapObjectSize / Map::kSize; |
Leon Clarke | e46be81 | 2010-01-19 14:06:41 +0000 | [diff] [blame] | 2640 | |
| 2641 | // Do map space compaction if there is a page gap. |
Leon Clarke | d91b9f7 | 2010-01-27 17:25:45 +0000 | [diff] [blame] | 2642 | int CompactionThreshold() { |
| 2643 | return kMapsPerPage * (max_map_space_pages_ - 1); |
| 2644 | } |
| 2645 | |
| 2646 | const int max_map_space_pages_; |
Leon Clarke | e46be81 | 2010-01-19 14:06:41 +0000 | [diff] [blame] | 2647 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2648 | public: |
| 2649 | TRACK_MEMORY("MapSpace") |
| 2650 | }; |
| 2651 | |
| 2652 | |
| 2653 | // ----------------------------------------------------------------------------- |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2654 | // Old space for simple property cell objects |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2655 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2656 | class CellSpace : public PagedSpace { |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2657 | public: |
| 2658 | // Creates a property cell space object with a maximum capacity. |
Steve Block | 44f0eee | 2011-05-26 01:26:41 +0100 | [diff] [blame] | 2659 | CellSpace(Heap* heap, intptr_t max_capacity, AllocationSpace id) |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2660 | : PagedSpace(heap, max_capacity, id, NOT_EXECUTABLE) {} |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2661 | |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2662 | virtual int RoundSizeDownToObjectAlignment(int size) { |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2663 | if (base::bits::IsPowerOfTwo32(Cell::kSize)) { |
| 2664 | return RoundDown(size, Cell::kSize); |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2665 | } else { |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2666 | return (size / Cell::kSize) * Cell::kSize; |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2667 | } |
| 2668 | } |
| 2669 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2670 | protected: |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2671 | virtual void VerifyObject(HeapObject* obj); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2672 | |
| 2673 | public: |
| 2674 | TRACK_MEMORY("CellSpace") |
| 2675 | }; |
| 2676 | |
| 2677 | |
| 2678 | // ----------------------------------------------------------------------------- |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2679 | // Old space for all global object property cell objects |
| 2680 | |
| 2681 | class PropertyCellSpace : public PagedSpace { |
| 2682 | public: |
| 2683 | // Creates a property cell space object with a maximum capacity. |
| 2684 | PropertyCellSpace(Heap* heap, intptr_t max_capacity, AllocationSpace id) |
| 2685 | : PagedSpace(heap, max_capacity, id, NOT_EXECUTABLE) {} |
| 2686 | |
| 2687 | virtual int RoundSizeDownToObjectAlignment(int size) { |
| 2688 | if (base::bits::IsPowerOfTwo32(PropertyCell::kSize)) { |
| 2689 | return RoundDown(size, PropertyCell::kSize); |
| 2690 | } else { |
| 2691 | return (size / PropertyCell::kSize) * PropertyCell::kSize; |
| 2692 | } |
| 2693 | } |
| 2694 | |
| 2695 | protected: |
| 2696 | virtual void VerifyObject(HeapObject* obj); |
| 2697 | |
| 2698 | public: |
| 2699 | TRACK_MEMORY("PropertyCellSpace") |
| 2700 | }; |
| 2701 | |
| 2702 | |
| 2703 | // ----------------------------------------------------------------------------- |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2704 | // Large objects ( > Page::kMaxHeapObjectSize ) are allocated and managed by |
| 2705 | // the large object space. A large object is allocated from OS heap with |
| 2706 | // extra padding bytes (Page::kPageSize + Page::kObjectStartOffset). |
| 2707 | // A large object always starts at Page::kObjectStartOffset to a page. |
| 2708 | // Large objects do not move during garbage collections. |
| 2709 | |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2710 | class LargeObjectSpace : public Space { |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2711 | public: |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2712 | LargeObjectSpace(Heap* heap, intptr_t max_capacity, AllocationSpace id); |
| 2713 | virtual ~LargeObjectSpace() {} |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2714 | |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2715 | // Initializes internal data structures. |
| 2716 | bool SetUp(); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2717 | |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2718 | // Releases internal resources, frees objects in this space. |
| 2719 | void TearDown(); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2720 | |
Ben Murdoch | 592a9fc | 2012-03-05 11:04:45 +0000 | [diff] [blame] | 2721 | static intptr_t ObjectSizeFor(intptr_t chunk_size) { |
| 2722 | if (chunk_size <= (Page::kPageSize + Page::kObjectStartOffset)) return 0; |
| 2723 | return chunk_size - Page::kPageSize - Page::kObjectStartOffset; |
| 2724 | } |
| 2725 | |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2726 | // Shared implementation of AllocateRaw, AllocateRawCode and |
| 2727 | // AllocateRawFixedArray. |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2728 | MUST_USE_RESULT AllocationResult |
| 2729 | AllocateRaw(int object_size, Executability executable); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2730 | |
Ben Murdoch | 7f4d5bd | 2010-06-15 11:15:29 +0100 | [diff] [blame] | 2731 | // Available bytes for objects in this space. |
Steve Block | 44f0eee | 2011-05-26 01:26:41 +0100 | [diff] [blame] | 2732 | inline intptr_t Available(); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2733 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2734 | virtual intptr_t Size() { return size_; } |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2735 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2736 | virtual intptr_t SizeOfObjects() { return objects_size_; } |
Shimeng (Simon) Wang | 8a31eba | 2010-12-06 19:01:33 -0800 | [diff] [blame] | 2737 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2738 | intptr_t MaximumCommittedMemory() { return maximum_committed_; } |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2739 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2740 | intptr_t CommittedMemory() { return Size(); } |
| 2741 | |
| 2742 | // Approximate amount of physical memory committed for this space. |
| 2743 | size_t CommittedPhysicalMemory(); |
| 2744 | |
| 2745 | int PageCount() { return page_count_; } |
| 2746 | |
| 2747 | // Finds an object for a given address, returns a Smi if it is not found. |
| 2748 | // The function iterates through all objects in this space, may be slow. |
| 2749 | Object* FindObject(Address a); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2750 | |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2751 | // Finds a large object page containing the given address, returns NULL |
Kristian Monsen | 80d68ea | 2010-09-08 11:05:35 +0100 | [diff] [blame] | 2752 | // if such a page doesn't exist. |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2753 | LargePage* FindPage(Address a); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2754 | |
| 2755 | // Frees unmarked objects. |
| 2756 | void FreeUnmarkedObjects(); |
| 2757 | |
| 2758 | // Checks whether a heap object is in this space; O(1). |
| 2759 | bool Contains(HeapObject* obj); |
| 2760 | |
| 2761 | // Checks whether the space is empty. |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2762 | bool IsEmpty() { return first_page_ == NULL; } |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2763 | |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2764 | LargePage* first_page() { return first_page_; } |
| 2765 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2766 | #ifdef VERIFY_HEAP |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2767 | virtual void Verify(); |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2768 | #endif |
| 2769 | |
| 2770 | #ifdef DEBUG |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2771 | virtual void Print(); |
| 2772 | void ReportStatistics(); |
| 2773 | void CollectCodeStatistics(); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2774 | #endif |
| 2775 | // Checks whether an address is in the object area in this space. It |
| 2776 | // iterates all objects in the space. May be slow. |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2777 | bool SlowContains(Address addr) { return FindObject(addr)->IsHeapObject(); } |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2778 | |
| 2779 | private: |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2780 | intptr_t max_capacity_; |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2781 | intptr_t maximum_committed_; |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2782 | // The head of the linked list of large object chunks. |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2783 | LargePage* first_page_; |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2784 | intptr_t size_; // allocated bytes |
| 2785 | int page_count_; // number of chunks |
Shimeng (Simon) Wang | 8a31eba | 2010-12-06 19:01:33 -0800 | [diff] [blame] | 2786 | intptr_t objects_size_; // size of objects |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2787 | // Map MemoryChunk::kAlignment-aligned chunks to large pages covering them |
| 2788 | HashMap chunk_map_; |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2789 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2790 | friend class LargeObjectIterator; |
| 2791 | |
| 2792 | public: |
| 2793 | TRACK_MEMORY("LargeObjectSpace") |
| 2794 | }; |
| 2795 | |
| 2796 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2797 | class LargeObjectIterator : public ObjectIterator { |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2798 | public: |
| 2799 | explicit LargeObjectIterator(LargeObjectSpace* space); |
| 2800 | LargeObjectIterator(LargeObjectSpace* space, HeapObjectCallback size_func); |
| 2801 | |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2802 | HeapObject* Next(); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2803 | |
| 2804 | // implementation of ObjectIterator. |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2805 | virtual HeapObject* next_object() { return Next(); } |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2806 | |
| 2807 | private: |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2808 | LargePage* current_; |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 2809 | HeapObjectCallback size_func_; |
| 2810 | }; |
| 2811 | |
| 2812 | |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2813 | // Iterates over the chunks (pages and large object pages) that can contain |
| 2814 | // pointers to new space. |
| 2815 | class PointerChunkIterator BASE_EMBEDDED { |
| 2816 | public: |
| 2817 | inline explicit PointerChunkIterator(Heap* heap); |
| 2818 | |
| 2819 | // Return NULL when the iterator is done. |
| 2820 | MemoryChunk* next() { |
| 2821 | switch (state_) { |
| 2822 | case kOldPointerState: { |
| 2823 | if (old_pointer_iterator_.has_next()) { |
| 2824 | return old_pointer_iterator_.next(); |
| 2825 | } |
| 2826 | state_ = kMapState; |
| 2827 | // Fall through. |
| 2828 | } |
| 2829 | case kMapState: { |
| 2830 | if (map_iterator_.has_next()) { |
| 2831 | return map_iterator_.next(); |
| 2832 | } |
| 2833 | state_ = kLargeObjectState; |
| 2834 | // Fall through. |
| 2835 | } |
| 2836 | case kLargeObjectState: { |
| 2837 | HeapObject* heap_object; |
| 2838 | do { |
| 2839 | heap_object = lo_iterator_.Next(); |
| 2840 | if (heap_object == NULL) { |
| 2841 | state_ = kFinishedState; |
| 2842 | return NULL; |
| 2843 | } |
| 2844 | // Fixed arrays are the only pointer-containing objects in large |
| 2845 | // object space. |
| 2846 | } while (!heap_object->IsFixedArray()); |
| 2847 | MemoryChunk* answer = MemoryChunk::FromAddress(heap_object->address()); |
| 2848 | return answer; |
| 2849 | } |
| 2850 | case kFinishedState: |
| 2851 | return NULL; |
| 2852 | default: |
| 2853 | break; |
| 2854 | } |
| 2855 | UNREACHABLE(); |
| 2856 | return NULL; |
| 2857 | } |
| 2858 | |
| 2859 | |
| 2860 | private: |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2861 | enum State { kOldPointerState, kMapState, kLargeObjectState, kFinishedState }; |
Ben Murdoch | 3ef787d | 2012-04-12 10:51:47 +0100 | [diff] [blame] | 2862 | State state_; |
| 2863 | PageIterator old_pointer_iterator_; |
| 2864 | PageIterator map_iterator_; |
| 2865 | LargeObjectIterator lo_iterator_; |
| 2866 | }; |
| 2867 | |
| 2868 | |
Steve Block | 44f0eee | 2011-05-26 01:26:41 +0100 | [diff] [blame] | 2869 | #ifdef DEBUG |
| 2870 | struct CommentStatistic { |
| 2871 | const char* comment; |
| 2872 | int size; |
| 2873 | int count; |
| 2874 | void Clear() { |
| 2875 | comment = NULL; |
| 2876 | size = 0; |
| 2877 | count = 0; |
| 2878 | } |
| 2879 | // Must be small, since an iteration is used for lookup. |
| 2880 | static const int kMaxComments = 64; |
| 2881 | }; |
| 2882 | #endif |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2883 | } |
| 2884 | } // namespace v8::internal |
Steve Block | 44f0eee | 2011-05-26 01:26:41 +0100 | [diff] [blame] | 2885 | |
Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 2886 | #endif // V8_HEAP_SPACES_H_ |