| OLD | NEW |
| 1 /* | 1 /* |
| 2 * Copyright (C) 2013 Google Inc. All rights reserved. | 2 * Copyright (C) 2013 Google Inc. All rights reserved. |
| 3 * | 3 * |
| 4 * Redistribution and use in source and binary forms, with or without | 4 * Redistribution and use in source and binary forms, with or without |
| 5 * modification, are permitted provided that the following conditions are | 5 * modification, are permitted provided that the following conditions are |
| 6 * met: | 6 * met: |
| 7 * | 7 * |
| 8 * * Redistributions of source code must retain the above copyright | 8 * * Redistributions of source code must retain the above copyright |
| 9 * notice, this list of conditions and the following disclaimer. | 9 * notice, this list of conditions and the following disclaimer. |
| 10 * * Redistributions in binary form must reproduce the above | 10 * * Redistributions in binary form must reproduce the above |
| (...skipping 15 matching lines...) Expand all Loading... |
| 26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT | 26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| 27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE | 27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| 28 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. | 28 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| 29 */ | 29 */ |
| 30 | 30 |
| 31 #ifndef Heap_h | 31 #ifndef Heap_h |
| 32 #define Heap_h | 32 #define Heap_h |
| 33 | 33 |
| 34 #include "platform/PlatformExport.h" | 34 #include "platform/PlatformExport.h" |
| 35 #include "platform/heap/GCInfo.h" | 35 #include "platform/heap/GCInfo.h" |
| 36 #include "platform/heap/HeapPage.h" |
| 36 #include "platform/heap/ThreadState.h" | 37 #include "platform/heap/ThreadState.h" |
| 37 #include "platform/heap/Visitor.h" | 38 #include "platform/heap/Visitor.h" |
| 38 #include "public/platform/WebThread.h" | |
| 39 #include "wtf/AddressSanitizer.h" | 39 #include "wtf/AddressSanitizer.h" |
| 40 #include "wtf/Assertions.h" | 40 #include "wtf/Assertions.h" |
| 41 #include "wtf/Atomics.h" | 41 #include "wtf/Atomics.h" |
| 42 #include "wtf/ContainerAnnotations.h" | |
| 43 #include "wtf/Forward.h" | 42 #include "wtf/Forward.h" |
| 44 #include "wtf/PageAllocator.h" | |
| 45 #include <stdint.h> | |
| 46 | 43 |
| 47 namespace blink { | 44 namespace blink { |
| 48 | 45 |
| 49 const size_t blinkPageSizeLog2 = 17; | |
| 50 const size_t blinkPageSize = 1 << blinkPageSizeLog2; | |
| 51 const size_t blinkPageOffsetMask = blinkPageSize - 1; | |
| 52 const size_t blinkPageBaseMask = ~blinkPageOffsetMask; | |
| 53 | |
| 54 // We allocate pages at random addresses but in groups of | |
| 55 // blinkPagesPerRegion at a given random address. We group pages to | |
| 56 // not spread out too much over the address space which would blow | |
| 57 // away the page tables and lead to bad performance. | |
| 58 const size_t blinkPagesPerRegion = 10; | |
| 59 | |
| 60 // TODO(nya): Replace this with something like #if ENABLE_NACL. | |
| 61 #if 0 | |
| 62 // NaCl's system page size is 64 KB. This causes a problem in Oilpan's heap | |
| 63 // layout because Oilpan allocates two guard pages for each blink page | |
| 64 // (whose size is 128 KB). So we don't use guard pages in NaCl. | |
| 65 const size_t blinkGuardPageSize = 0; | |
| 66 #else | |
| 67 const size_t blinkGuardPageSize = WTF::kSystemPageSize; | |
| 68 #endif | |
| 69 | |
| 70 // Double precision floats are more efficient when 8 byte aligned, so we 8 byte | |
| 71 // align all allocations even on 32 bit. | |
| 72 const size_t allocationGranularity = 8; | |
| 73 const size_t allocationMask = allocationGranularity - 1; | |
| 74 const size_t objectStartBitMapSize = (blinkPageSize + ((8 * allocationGranularit
y) - 1)) / (8 * allocationGranularity); | |
| 75 const size_t reservedForObjectBitMap = ((objectStartBitMapSize + allocationMask)
& ~allocationMask); | |
| 76 const size_t maxHeapObjectSizeLog2 = 27; | |
| 77 const size_t maxHeapObjectSize = 1 << maxHeapObjectSizeLog2; | |
| 78 const size_t largeObjectSizeThreshold = blinkPageSize / 2; | |
| 79 | |
| 80 // A zap value used for freed memory that is allowed to be added to the free | |
| 81 // list in the next addToFreeList(). | |
| 82 const uint8_t reuseAllowedZapValue = 0x2a; | |
| 83 // A zap value used for freed memory that is forbidden to be added to the free | |
| 84 // list in the next addToFreeList(). | |
| 85 const uint8_t reuseForbiddenZapValue = 0x2c; | |
| 86 | |
| 87 // In non-production builds, memory is zapped when it's freed. The zapped | |
| 88 // memory is zeroed out when the memory is reused in Heap::allocateObject(). | |
| 89 // In production builds, memory is not zapped (for performance). The memory | |
| 90 // is just zeroed out when it is added to the free list. | |
| 91 #if defined(MEMORY_SANITIZER) | |
| 92 // TODO(kojii): We actually need __msan_poison/unpoison here, but it'll be | |
| 93 // added later. | |
| 94 #define SET_MEMORY_INACCESSIBLE(address, size) \ | |
| 95 FreeList::zapFreedMemory(address, size); | |
| 96 #define SET_MEMORY_ACCESSIBLE(address, size) \ | |
| 97 memset((address), 0, (size)) | |
| 98 #elif ENABLE(ASSERT) || defined(LEAK_SANITIZER) || defined(ADDRESS_SANITIZER) | |
| 99 #define SET_MEMORY_INACCESSIBLE(address, size) \ | |
| 100 FreeList::zapFreedMemory(address, size); \ | |
| 101 ASAN_POISON_MEMORY_REGION(address, size) | |
| 102 #define SET_MEMORY_ACCESSIBLE(address, size) \ | |
| 103 ASAN_UNPOISON_MEMORY_REGION(address, size); \ | |
| 104 memset((address), 0, (size)) | |
| 105 #else | |
| 106 #define SET_MEMORY_INACCESSIBLE(address, size) memset((address), 0, (size)) | |
| 107 #define SET_MEMORY_ACCESSIBLE(address, size) do { } while (false) | |
| 108 #endif | |
| 109 | |
| 110 class CallbackStack; | |
| 111 class FreePagePool; | |
| 112 class NormalPageHeap; | |
| 113 class OrphanedPagePool; | |
| 114 class PageMemory; | |
| 115 class PageMemoryRegion; | |
| 116 class WebProcessMemoryDump; | |
| 117 | |
| 118 #if ENABLE(GC_PROFILING) | |
| 119 class TracedValue; | |
| 120 #endif | |
| 121 | |
| 122 // HeapObjectHeader is 4 byte (32 bit) that has the following layout: | |
| 123 // | |
| 124 // | gcInfoIndex (14 bit) | DOM mark bit (1 bit) | size (14 bit) | dead bit (1 b
it) | freed bit (1 bit) | mark bit (1 bit) | | |
| 125 // | |
| 126 // - For non-large objects, 14 bit is enough for |size| because the blink | |
| 127 // page size is 2^17 byte and each object is guaranteed to be aligned with | |
| 128 // 2^3 byte. | |
| 129 // - For large objects, |size| is 0. The actual size of a large object is | |
| 130 // stored in LargeObjectPage::m_payloadSize. | |
| 131 // - 1 bit used to mark DOM trees for V8. | |
| 132 // - 14 bit is enough for gcInfoIndex because there are less than 2^14 types | |
| 133 // in Blink. | |
| 134 const size_t headerDOMMarkBitMask = 1u << 17; | |
| 135 const size_t headerGCInfoIndexShift = 18; | |
| 136 const size_t headerGCInfoIndexMask = (static_cast<size_t>((1 << 14) - 1)) << hea
derGCInfoIndexShift; | |
| 137 const size_t headerSizeMask = (static_cast<size_t>((1 << 14) - 1)) << 3; | |
| 138 const size_t headerMarkBitMask = 1; | |
| 139 const size_t headerFreedBitMask = 2; | |
| 140 // The dead bit is used for objects that have gone through a GC marking, but did | |
| 141 // not get swept before a new GC started. In that case we set the dead bit on | |
| 142 // objects that were not marked in the previous GC to ensure we are not tracing | |
| 143 // them via a conservatively found pointer. Tracing dead objects could lead to | |
| 144 // tracing of already finalized objects in another thread's heap which is a | |
| 145 // use-after-free situation. | |
| 146 const size_t headerDeadBitMask = 4; | |
| 147 // On free-list entries we reuse the dead bit to distinguish a normal free-list | |
| 148 // entry from one that has been promptly freed. | |
| 149 const size_t headerPromptlyFreedBitMask = headerFreedBitMask | headerDeadBitMask
; | |
| 150 const size_t largeObjectSizeInHeader = 0; | |
| 151 const size_t gcInfoIndexForFreeListHeader = 0; | |
| 152 const size_t nonLargeObjectPageSizeMax = 1 << 17; | |
| 153 | |
| 154 static_assert(nonLargeObjectPageSizeMax >= blinkPageSize, "max size supported by
HeapObjectHeader must at least be blinkPageSize"); | |
| 155 | |
| 156 class PLATFORM_EXPORT HeapObjectHeader { | |
| 157 public: | |
| 158 // If gcInfoIndex is 0, this header is interpreted as a free list header. | |
| 159 NO_SANITIZE_ADDRESS | |
| 160 HeapObjectHeader(size_t size, size_t gcInfoIndex) | |
| 161 { | |
| 162 #if ENABLE(ASSERT) | |
| 163 m_magic = magic; | |
| 164 #endif | |
| 165 #if ENABLE(GC_PROFILING) | |
| 166 m_age = 0; | |
| 167 #endif | |
| 168 // sizeof(HeapObjectHeader) must be equal to or smaller than | |
| 169 // allocationGranurarity, because HeapObjectHeader is used as a header | |
| 170 // for an freed entry. Given that the smallest entry size is | |
| 171 // allocationGranurarity, HeapObjectHeader must fit into the size. | |
| 172 static_assert(sizeof(HeapObjectHeader) <= allocationGranularity, "size o
f HeapObjectHeader must be smaller than allocationGranularity"); | |
| 173 #if CPU(64BIT) | |
| 174 static_assert(sizeof(HeapObjectHeader) == 8, "size of HeapObjectHeader m
ust be 8 byte aligned"); | |
| 175 #endif | |
| 176 | |
| 177 ASSERT(gcInfoIndex < GCInfoTable::maxIndex); | |
| 178 ASSERT(size < nonLargeObjectPageSizeMax); | |
| 179 ASSERT(!(size & allocationMask)); | |
| 180 m_encoded = (gcInfoIndex << headerGCInfoIndexShift) | size | (gcInfoInde
x ? 0 : headerFreedBitMask); | |
| 181 } | |
| 182 | |
| 183 NO_SANITIZE_ADDRESS | |
| 184 bool isFree() const { return m_encoded & headerFreedBitMask; } | |
| 185 NO_SANITIZE_ADDRESS | |
| 186 bool isPromptlyFreed() const { return (m_encoded & headerPromptlyFreedBitMas
k) == headerPromptlyFreedBitMask; } | |
| 187 NO_SANITIZE_ADDRESS | |
| 188 void markPromptlyFreed() { m_encoded |= headerPromptlyFreedBitMask; } | |
| 189 size_t size() const; | |
| 190 | |
| 191 NO_SANITIZE_ADDRESS | |
| 192 size_t gcInfoIndex() const { return (m_encoded & headerGCInfoIndexMask) >> h
eaderGCInfoIndexShift; } | |
| 193 NO_SANITIZE_ADDRESS | |
| 194 void setSize(size_t size) { m_encoded = size | (m_encoded & ~headerSizeMask)
; } | |
| 195 bool isMarked() const; | |
| 196 void mark(); | |
| 197 void unmark(); | |
| 198 void markDead(); | |
| 199 bool isDead() const; | |
| 200 | |
| 201 Address payload(); | |
| 202 size_t payloadSize(); | |
| 203 Address payloadEnd(); | |
| 204 | |
| 205 #if ENABLE(ASSERT) | |
| 206 bool checkHeader() const; | |
| 207 // Zap magic number with a new magic number that means there was once an | |
| 208 // object allocated here, but it was freed because nobody marked it during | |
| 209 // GC. | |
| 210 void zapMagic(); | |
| 211 #endif | |
| 212 | |
| 213 void finalize(Address, size_t); | |
| 214 static HeapObjectHeader* fromPayload(const void*); | |
| 215 | |
| 216 static const uint16_t magic = 0xfff1; | |
| 217 static const uint16_t zappedMagic = 0x4321; | |
| 218 | |
| 219 #if ENABLE(GC_PROFILING) | |
| 220 NO_SANITIZE_ADDRESS | |
| 221 size_t encodedSize() const { return m_encoded; } | |
| 222 | |
| 223 NO_SANITIZE_ADDRESS | |
| 224 size_t age() const { return m_age; } | |
| 225 | |
| 226 NO_SANITIZE_ADDRESS | |
| 227 void incrementAge() | |
| 228 { | |
| 229 if (m_age < maxHeapObjectAge) | |
| 230 m_age++; | |
| 231 } | |
| 232 #endif | |
| 233 | |
| 234 #if !ENABLE(ASSERT) && !ENABLE(GC_PROFILING) && CPU(64BIT) | |
| 235 // This method is needed just to avoid compilers from removing m_padding. | |
| 236 uint64_t unusedMethod() const { return m_padding; } | |
| 237 #endif | |
| 238 | |
| 239 private: | |
| 240 uint32_t m_encoded; | |
| 241 #if ENABLE(ASSERT) | |
| 242 uint16_t m_magic; | |
| 243 #endif | |
| 244 #if ENABLE(GC_PROFILING) | |
| 245 uint8_t m_age; | |
| 246 #endif | |
| 247 | |
| 248 // In 64 bit architectures, we intentionally add 4 byte padding immediately | |
| 249 // after the HeapHeaderObject. This is because: | |
| 250 // | |
| 251 // | HeapHeaderObject (4 byte) | padding (4 byte) | object payload (8 * n by
te) | | |
| 252 // ^8 byte aligned ^8 byte aligned | |
| 253 // | |
| 254 // is better than: | |
| 255 // | |
| 256 // | HeapHeaderObject (4 byte) | object payload (8 * n byte) | padding (4 by
te) | | |
| 257 // ^4 byte aligned ^8 byte aligned ^4 byte aligned | |
| 258 // | |
| 259 // since the former layout aligns both header and payload to 8 byte. | |
| 260 #if !ENABLE(ASSERT) && !ENABLE(GC_PROFILING) && CPU(64BIT) | |
| 261 uint32_t m_padding; | |
| 262 #endif | |
| 263 }; | |
| 264 | |
| 265 class FreeListEntry final : public HeapObjectHeader { | |
| 266 public: | |
| 267 NO_SANITIZE_ADDRESS | |
| 268 explicit FreeListEntry(size_t size) | |
| 269 : HeapObjectHeader(size, gcInfoIndexForFreeListHeader) | |
| 270 , m_next(nullptr) | |
| 271 { | |
| 272 #if ENABLE(ASSERT) | |
| 273 ASSERT(size >= sizeof(HeapObjectHeader)); | |
| 274 zapMagic(); | |
| 275 #endif | |
| 276 } | |
| 277 | |
| 278 Address address() { return reinterpret_cast<Address>(this); } | |
| 279 | |
| 280 NO_SANITIZE_ADDRESS | |
| 281 void unlink(FreeListEntry** prevNext) | |
| 282 { | |
| 283 *prevNext = m_next; | |
| 284 m_next = nullptr; | |
| 285 } | |
| 286 | |
| 287 NO_SANITIZE_ADDRESS | |
| 288 void link(FreeListEntry** prevNext) | |
| 289 { | |
| 290 m_next = *prevNext; | |
| 291 *prevNext = this; | |
| 292 } | |
| 293 | |
| 294 NO_SANITIZE_ADDRESS | |
| 295 FreeListEntry* next() const { return m_next; } | |
| 296 | |
| 297 NO_SANITIZE_ADDRESS | |
| 298 void append(FreeListEntry* next) | |
| 299 { | |
| 300 ASSERT(!m_next); | |
| 301 m_next = next; | |
| 302 } | |
| 303 | |
| 304 private: | |
| 305 FreeListEntry* m_next; | |
| 306 }; | |
| 307 | |
| 308 // Blink heap pages are set up with a guard page before and after the payload. | |
| 309 inline size_t blinkPagePayloadSize() | |
| 310 { | |
| 311 return blinkPageSize - 2 * blinkGuardPageSize; | |
| 312 } | |
| 313 | |
| 314 // Blink heap pages are aligned to the Blink heap page size. | |
| 315 // Therefore, the start of a Blink page can be obtained by | |
| 316 // rounding down to the Blink page size. | |
| 317 inline Address roundToBlinkPageStart(Address address) | |
| 318 { | |
| 319 return reinterpret_cast<Address>(reinterpret_cast<uintptr_t>(address) & blin
kPageBaseMask); | |
| 320 } | |
| 321 | |
| 322 inline Address roundToBlinkPageEnd(Address address) | |
| 323 { | |
| 324 return reinterpret_cast<Address>(reinterpret_cast<uintptr_t>(address - 1) &
blinkPageBaseMask) + blinkPageSize; | |
| 325 } | |
| 326 | |
| 327 // Masks an address down to the enclosing blink page base address. | |
| 328 inline Address blinkPageAddress(Address address) | |
| 329 { | |
| 330 return reinterpret_cast<Address>(reinterpret_cast<uintptr_t>(address) & blin
kPageBaseMask); | |
| 331 } | |
| 332 | |
| 333 inline bool vTableInitialized(void* objectPointer) | |
| 334 { | |
| 335 return !!(*reinterpret_cast<Address*>(objectPointer)); | |
| 336 } | |
| 337 | |
| 338 #if ENABLE(ASSERT) | |
| 339 // Sanity check for a page header address: the address of the page | |
| 340 // header should be OS page size away from being Blink page size | |
| 341 // aligned. | |
| 342 inline bool isPageHeaderAddress(Address address) | |
| 343 { | |
| 344 return !((reinterpret_cast<uintptr_t>(address) & blinkPageOffsetMask) - blin
kGuardPageSize); | |
| 345 } | |
| 346 #endif | |
| 347 | |
| 348 // BasePage is a base class for NormalPage and LargeObjectPage. | |
| 349 // | |
| 350 // - NormalPage is a page whose size is |blinkPageSize|. NormalPage can contain | |
| 351 // multiple objects in the page. An object whose size is smaller than | |
| 352 // |largeObjectSizeThreshold| is stored in NormalPage. | |
| 353 // | |
| 354 // - LargeObjectPage is a page that contains only one object. The object size | |
| 355 // is arbitrary. An object whose size is larger than |blinkPageSize| is stored | |
| 356 // as a single project in LargeObjectPage. | |
| 357 // | |
| 358 // Note: An object whose size is between |largeObjectSizeThreshold| and | |
| 359 // |blinkPageSize| can go to either of NormalPage or LargeObjectPage. | |
| 360 class BasePage { | |
| 361 public: | |
| 362 BasePage(PageMemory*, BaseHeap*); | |
| 363 virtual ~BasePage() { } | |
| 364 | |
| 365 void link(BasePage** previousNext) | |
| 366 { | |
| 367 m_next = *previousNext; | |
| 368 *previousNext = this; | |
| 369 } | |
| 370 void unlink(BasePage** previousNext) | |
| 371 { | |
| 372 *previousNext = m_next; | |
| 373 m_next = nullptr; | |
| 374 } | |
| 375 BasePage* next() const { return m_next; } | |
| 376 | |
| 377 // virtual methods are slow. So performance-sensitive methods | |
| 378 // should be defined as non-virtual methods on NormalPage and LargeObjectPag
e. | |
| 379 // The following methods are not performance-sensitive. | |
| 380 virtual size_t objectPayloadSizeForTesting() = 0; | |
| 381 virtual bool isEmpty() = 0; | |
| 382 virtual void removeFromHeap() = 0; | |
| 383 virtual void sweep() = 0; | |
| 384 virtual void makeConsistentForGC() = 0; | |
| 385 virtual void makeConsistentForMutator() = 0; | |
| 386 | |
| 387 #if defined(ADDRESS_SANITIZER) | |
| 388 virtual void poisonObjects(ThreadState::ObjectsToPoison, ThreadState::Poison
ing) = 0; | |
| 389 #endif | |
| 390 // Check if the given address points to an object in this | |
| 391 // heap page. If so, find the start of that object and mark it | |
| 392 // using the given Visitor. Otherwise do nothing. The pointer must | |
| 393 // be within the same aligned blinkPageSize as the this-pointer. | |
| 394 // | |
| 395 // This is used during conservative stack scanning to | |
| 396 // conservatively mark all objects that could be referenced from | |
| 397 // the stack. | |
| 398 virtual void checkAndMarkPointer(Visitor*, Address) = 0; | |
| 399 virtual void markOrphaned(); | |
| 400 | |
| 401 virtual void takeSnapshot(String dumpBaseName, size_t pageIndex, ThreadState
::GCSnapshotInfo&, size_t* outFreeSize, size_t* outFreeCount) = 0; | |
| 402 #if ENABLE(GC_PROFILING) | |
| 403 virtual const GCInfo* findGCInfo(Address) = 0; | |
| 404 virtual void snapshot(TracedValue*, ThreadState::SnapshotInfo*) = 0; | |
| 405 virtual void incrementMarkedObjectsAge() = 0; | |
| 406 virtual void countMarkedObjects(ClassAgeCountsMap&) = 0; | |
| 407 virtual void countObjectsToSweep(ClassAgeCountsMap&) = 0; | |
| 408 #endif | |
| 409 #if ENABLE(ASSERT) || ENABLE(GC_PROFILING) | |
| 410 virtual bool contains(Address) = 0; | |
| 411 #endif | |
| 412 virtual size_t size() = 0; | |
| 413 virtual bool isLargeObjectPage() { return false; } | |
| 414 | |
| 415 Address address() { return reinterpret_cast<Address>(this); } | |
| 416 PageMemory* storage() const { return m_storage; } | |
| 417 BaseHeap* heap() const { return m_heap; } | |
| 418 bool orphaned() { return !m_heap; } | |
| 419 bool terminating() { return m_terminating; } | |
| 420 void setTerminating() { m_terminating = true; } | |
| 421 | |
| 422 // Returns true if this page has been swept by the ongoing lazy sweep. | |
| 423 bool hasBeenSwept() const { return m_swept; } | |
| 424 | |
| 425 void markAsSwept() | |
| 426 { | |
| 427 ASSERT(!m_swept); | |
| 428 m_swept = true; | |
| 429 } | |
| 430 | |
| 431 void markAsUnswept() | |
| 432 { | |
| 433 ASSERT(m_swept); | |
| 434 m_swept = false; | |
| 435 } | |
| 436 | |
| 437 private: | |
| 438 PageMemory* m_storage; | |
| 439 BaseHeap* m_heap; | |
| 440 BasePage* m_next; | |
| 441 // Whether the page is part of a terminating thread or not. | |
| 442 bool m_terminating; | |
| 443 | |
| 444 // Track the sweeping state of a page. Set to true once | |
| 445 // the lazy sweep completes has processed it. | |
| 446 // | |
| 447 // Set to false at the start of a sweep, true upon completion | |
| 448 // of lazy sweeping. | |
| 449 bool m_swept; | |
| 450 friend class BaseHeap; | |
| 451 }; | |
| 452 | |
| 453 class NormalPage final : public BasePage { | |
| 454 public: | |
| 455 NormalPage(PageMemory*, BaseHeap*); | |
| 456 | |
| 457 Address payload() | |
| 458 { | |
| 459 return address() + pageHeaderSize(); | |
| 460 } | |
| 461 size_t payloadSize() | |
| 462 { | |
| 463 return (blinkPagePayloadSize() - pageHeaderSize()) & ~allocationMask; | |
| 464 } | |
| 465 Address payloadEnd() { return payload() + payloadSize(); } | |
| 466 bool containedInObjectPayload(Address address) | |
| 467 { | |
| 468 return payload() <= address && address < payloadEnd(); | |
| 469 } | |
| 470 | |
| 471 size_t objectPayloadSizeForTesting() override; | |
| 472 bool isEmpty() override; | |
| 473 void removeFromHeap() override; | |
| 474 void sweep() override; | |
| 475 void makeConsistentForGC() override; | |
| 476 void makeConsistentForMutator() override; | |
| 477 #if defined(ADDRESS_SANITIZER) | |
| 478 void poisonObjects(ThreadState::ObjectsToPoison, ThreadState::Poisoning) ove
rride; | |
| 479 #endif | |
| 480 void checkAndMarkPointer(Visitor*, Address) override; | |
| 481 void markOrphaned() override; | |
| 482 | |
| 483 void takeSnapshot(String dumpBaseName, size_t pageIndex, ThreadState::GCSnap
shotInfo&, size_t* outFreeSize, size_t* outFreeCount) override; | |
| 484 #if ENABLE(GC_PROFILING) | |
| 485 const GCInfo* findGCInfo(Address) override; | |
| 486 void snapshot(TracedValue*, ThreadState::SnapshotInfo*) override; | |
| 487 void incrementMarkedObjectsAge() override; | |
| 488 void countMarkedObjects(ClassAgeCountsMap&) override; | |
| 489 void countObjectsToSweep(ClassAgeCountsMap&) override; | |
| 490 #endif | |
| 491 #if ENABLE(ASSERT) || ENABLE(GC_PROFILING) | |
| 492 // Returns true for the whole blinkPageSize page that the page is on, even | |
| 493 // for the header, and the unmapped guard page at the start. That ensures | |
| 494 // the result can be used to populate the negative page cache. | |
| 495 bool contains(Address) override; | |
| 496 #endif | |
| 497 size_t size() override { return blinkPageSize; } | |
| 498 static size_t pageHeaderSize() | |
| 499 { | |
| 500 // Compute the amount of padding we have to add to a header to make | |
| 501 // the size of the header plus the padding a multiple of 8 bytes. | |
| 502 size_t paddingSize = (sizeof(NormalPage) + allocationGranularity - (size
of(HeapObjectHeader) % allocationGranularity)) % allocationGranularity; | |
| 503 return sizeof(NormalPage) + paddingSize; | |
| 504 } | |
| 505 | |
| 506 | |
| 507 NormalPageHeap* heapForNormalPage(); | |
| 508 void clearObjectStartBitMap(); | |
| 509 | |
| 510 private: | |
| 511 HeapObjectHeader* findHeaderFromAddress(Address); | |
| 512 void populateObjectStartBitMap(); | |
| 513 bool isObjectStartBitMapComputed() { return m_objectStartBitMapComputed; } | |
| 514 | |
| 515 bool m_objectStartBitMapComputed; | |
| 516 uint8_t m_objectStartBitMap[reservedForObjectBitMap]; | |
| 517 }; | |
| 518 | |
| 519 // Large allocations are allocated as separate objects and linked in a list. | |
| 520 // | |
| 521 // In order to use the same memory allocation routines for everything allocated | |
| 522 // in the heap, large objects are considered heap pages containing only one | |
| 523 // object. | |
| 524 class LargeObjectPage final : public BasePage { | |
| 525 public: | |
| 526 LargeObjectPage(PageMemory*, BaseHeap*, size_t); | |
| 527 | |
| 528 Address payload() { return heapObjectHeader()->payload(); } | |
| 529 size_t payloadSize() { return m_payloadSize; } | |
| 530 Address payloadEnd() { return payload() + payloadSize(); } | |
| 531 bool containedInObjectPayload(Address address) | |
| 532 { | |
| 533 return payload() <= address && address < payloadEnd(); | |
| 534 } | |
| 535 | |
| 536 size_t objectPayloadSizeForTesting() override; | |
| 537 bool isEmpty() override; | |
| 538 void removeFromHeap() override; | |
| 539 void sweep() override; | |
| 540 void makeConsistentForGC() override; | |
| 541 void makeConsistentForMutator() override; | |
| 542 #if defined(ADDRESS_SANITIZER) | |
| 543 void poisonObjects(ThreadState::ObjectsToPoison, ThreadState::Poisoning) ove
rride; | |
| 544 #endif | |
| 545 void checkAndMarkPointer(Visitor*, Address) override; | |
| 546 void markOrphaned() override; | |
| 547 | |
| 548 void takeSnapshot(String dumpBaseName, size_t pageIndex, ThreadState::GCSnap
shotInfo&, size_t* outFreeSize, size_t* outFreeCount) override; | |
| 549 #if ENABLE(GC_PROFILING) | |
| 550 const GCInfo* findGCInfo(Address) override; | |
| 551 void snapshot(TracedValue*, ThreadState::SnapshotInfo*) override; | |
| 552 void incrementMarkedObjectsAge() override; | |
| 553 void countMarkedObjects(ClassAgeCountsMap&) override; | |
| 554 void countObjectsToSweep(ClassAgeCountsMap&) override; | |
| 555 #endif | |
| 556 #if ENABLE(ASSERT) || ENABLE(GC_PROFILING) | |
| 557 // Returns true for any address that is on one of the pages that this | |
| 558 // large object uses. That ensures that we can use a negative result to | |
| 559 // populate the negative page cache. | |
| 560 bool contains(Address) override; | |
| 561 #endif | |
| 562 virtual size_t size() | |
| 563 { | |
| 564 return pageHeaderSize() + sizeof(HeapObjectHeader) + m_payloadSize; | |
| 565 } | |
| 566 static size_t pageHeaderSize() | |
| 567 { | |
| 568 // Compute the amount of padding we have to add to a header to make | |
| 569 // the size of the header plus the padding a multiple of 8 bytes. | |
| 570 size_t paddingSize = (sizeof(LargeObjectPage) + allocationGranularity -
(sizeof(HeapObjectHeader) % allocationGranularity)) % allocationGranularity; | |
| 571 return sizeof(LargeObjectPage) + paddingSize; | |
| 572 } | |
| 573 bool isLargeObjectPage() override { return true; } | |
| 574 | |
| 575 HeapObjectHeader* heapObjectHeader() | |
| 576 { | |
| 577 Address headerAddress = address() + pageHeaderSize(); | |
| 578 return reinterpret_cast<HeapObjectHeader*>(headerAddress); | |
| 579 } | |
| 580 | |
| 581 #ifdef ANNOTATE_CONTIGUOUS_CONTAINER | |
| 582 void setIsVectorBackingPage() { m_isVectorBackingPage = true; } | |
| 583 bool isVectorBackingPage() const { return m_isVectorBackingPage; } | |
| 584 #endif | |
| 585 | |
| 586 private: | |
| 587 | |
| 588 size_t m_payloadSize; | |
| 589 #ifdef ANNOTATE_CONTIGUOUS_CONTAINER | |
| 590 bool m_isVectorBackingPage; | |
| 591 #endif | |
| 592 }; | |
| 593 | |
| 594 // A HeapDoesNotContainCache provides a fast way of taking an arbitrary | |
| 595 // pointer-sized word, and determining whether it cannot be interpreted as a | |
| 596 // pointer to an area that is managed by the garbage collected Blink heap. This | |
| 597 // is a cache of 'pages' that have previously been determined to be wholly | |
| 598 // outside of the heap. The size of these pages must be smaller than the | |
| 599 // allocation alignment of the heap pages. We determine off-heap-ness by | |
| 600 // rounding down the pointer to the nearest page and looking up the page in the | |
| 601 // cache. If there is a miss in the cache we can determine the status of the | |
| 602 // pointer precisely using the heap RegionTree. | |
| 603 // | |
| 604 // The HeapDoesNotContainCache is a negative cache, so it must be flushed when | |
| 605 // memory is added to the heap. | |
| 606 class HeapDoesNotContainCache { | |
| 607 public: | |
| 608 HeapDoesNotContainCache() | |
| 609 : m_entries(adoptArrayPtr(new Address[HeapDoesNotContainCache::numberOfE
ntries])) | |
| 610 , m_hasEntries(false) | |
| 611 { | |
| 612 // Start by flushing the cache in a non-empty state to initialize all th
e cache entries. | |
| 613 for (int i = 0; i < numberOfEntries; ++i) | |
| 614 m_entries[i] = nullptr; | |
| 615 } | |
| 616 | |
| 617 void flush(); | |
| 618 bool isEmpty() { return !m_hasEntries; } | |
| 619 | |
| 620 // Perform a lookup in the cache. | |
| 621 // | |
| 622 // If lookup returns false, the argument address was not found in | |
| 623 // the cache and it is unknown if the address is in the Blink | |
| 624 // heap. | |
| 625 // | |
| 626 // If lookup returns true, the argument address was found in the | |
| 627 // cache which means the address is not in the heap. | |
| 628 PLATFORM_EXPORT bool lookup(Address); | |
| 629 | |
| 630 // Add an entry to the cache. | |
| 631 PLATFORM_EXPORT void addEntry(Address); | |
| 632 | |
| 633 private: | |
| 634 static const int numberOfEntriesLog2 = 12; | |
| 635 static const int numberOfEntries = 1 << numberOfEntriesLog2; | |
| 636 | |
| 637 static size_t hash(Address); | |
| 638 | |
| 639 WTF::OwnPtr<Address[]> m_entries; | |
| 640 bool m_hasEntries; | |
| 641 }; | |
| 642 | |
| 643 class FreeList { | |
| 644 public: | |
| 645 FreeList(); | |
| 646 | |
| 647 void addToFreeList(Address, size_t); | |
| 648 void clear(); | |
| 649 | |
| 650 // Returns a bucket number for inserting a FreeListEntry of a given size. | |
| 651 // All FreeListEntries in the given bucket, n, have size >= 2^n. | |
| 652 static int bucketIndexForSize(size_t); | |
| 653 | |
| 654 // Returns true if the freelist snapshot is captured. | |
| 655 bool takeSnapshot(const String& dumpBaseName); | |
| 656 | |
| 657 #if ENABLE(GC_PROFILING) | |
| 658 struct PerBucketFreeListStats { | |
| 659 size_t entryCount; | |
| 660 size_t freeSize; | |
| 661 | |
| 662 PerBucketFreeListStats() : entryCount(0), freeSize(0) { } | |
| 663 }; | |
| 664 | |
| 665 void getFreeSizeStats(PerBucketFreeListStats bucketStats[], size_t& totalSiz
e) const; | |
| 666 #endif | |
| 667 | |
| 668 #if ENABLE(ASSERT) || defined(LEAK_SANITIZER) || defined(ADDRESS_SANITIZER) || d
efined(MEMORY_SANITIZER) | |
| 669 static void zapFreedMemory(Address, size_t); | |
| 670 #endif | |
| 671 | |
| 672 private: | |
| 673 int m_biggestFreeListIndex; | |
| 674 | |
| 675 // All FreeListEntries in the nth list have size >= 2^n. | |
| 676 FreeListEntry* m_freeLists[blinkPageSizeLog2]; | |
| 677 | |
| 678 friend class NormalPageHeap; | |
| 679 }; | |
| 680 | |
| 681 // Each thread has a number of thread heaps (e.g., Generic heaps, | |
| 682 // typed heaps for Node, heaps for collection backings etc) | |
| 683 // and BaseHeap represents each thread heap. | |
| 684 // | |
| 685 // BaseHeap is a parent class of NormalPageHeap and LargeObjectHeap. | |
| 686 // NormalPageHeap represents a heap that contains NormalPages | |
| 687 // and LargeObjectHeap represents a heap that contains LargeObjectPages. | |
| 688 class PLATFORM_EXPORT BaseHeap { | |
| 689 public: | |
| 690 BaseHeap(ThreadState*, int); | |
| 691 virtual ~BaseHeap(); | |
| 692 void cleanupPages(); | |
| 693 | |
| 694 void takeSnapshot(const String& dumpBaseName, ThreadState::GCSnapshotInfo&); | |
| 695 #if ENABLE(ASSERT) || ENABLE(GC_PROFILING) | |
| 696 BasePage* findPageFromAddress(Address); | |
| 697 #endif | |
| 698 virtual void takeFreelistSnapshot(const String& dumpBaseName) { } | |
| 699 #if ENABLE(GC_PROFILING) | |
| 700 void snapshot(TracedValue*, ThreadState::SnapshotInfo*); | |
| 701 virtual void snapshotFreeList(TracedValue&) { } | |
| 702 | |
| 703 void countMarkedObjects(ClassAgeCountsMap&) const; | |
| 704 void countObjectsToSweep(ClassAgeCountsMap&) const; | |
| 705 void incrementMarkedObjectsAge(); | |
| 706 #endif | |
| 707 | |
| 708 virtual void clearFreeLists() { } | |
| 709 void makeConsistentForGC(); | |
| 710 void makeConsistentForMutator(); | |
| 711 #if ENABLE(ASSERT) | |
| 712 virtual bool isConsistentForGC() = 0; | |
| 713 #endif | |
| 714 size_t objectPayloadSizeForTesting(); | |
| 715 void prepareHeapForTermination(); | |
| 716 void prepareForSweep(); | |
| 717 #if defined(ADDRESS_SANITIZER) | |
| 718 void poisonHeap(ThreadState::ObjectsToPoison, ThreadState::Poisoning); | |
| 719 #endif | |
| 720 Address lazySweep(size_t, size_t gcInfoIndex); | |
| 721 void sweepUnsweptPage(); | |
| 722 // Returns true if we have swept all pages within the deadline. | |
| 723 // Returns false otherwise. | |
| 724 bool lazySweepWithDeadline(double deadlineSeconds); | |
| 725 void completeSweep(); | |
| 726 | |
| 727 ThreadState* threadState() { return m_threadState; } | |
| 728 int heapIndex() const { return m_index; } | |
| 729 | |
| 730 protected: | |
| 731 BasePage* m_firstPage; | |
| 732 BasePage* m_firstUnsweptPage; | |
| 733 | |
| 734 private: | |
| 735 virtual Address lazySweepPages(size_t, size_t gcInfoIndex) = 0; | |
| 736 | |
| 737 ThreadState* m_threadState; | |
| 738 | |
| 739 // Index into the page pools. This is used to ensure that the pages of the | |
| 740 // same type go into the correct page pool and thus avoid type confusion. | |
| 741 int m_index; | |
| 742 }; | |
| 743 | |
| 744 class PLATFORM_EXPORT NormalPageHeap final : public BaseHeap { | |
| 745 public: | |
| 746 NormalPageHeap(ThreadState*, int); | |
| 747 void addToFreeList(Address address, size_t size) | |
| 748 { | |
| 749 ASSERT(findPageFromAddress(address)); | |
| 750 ASSERT(findPageFromAddress(address + size - 1)); | |
| 751 m_freeList.addToFreeList(address, size); | |
| 752 } | |
| 753 void clearFreeLists() override; | |
| 754 #if ENABLE(ASSERT) | |
| 755 bool isConsistentForGC() override; | |
| 756 bool pagesToBeSweptContains(Address); | |
| 757 #endif | |
| 758 void takeFreelistSnapshot(const String& dumpBaseName) override; | |
| 759 #if ENABLE(GC_PROFILING) | |
| 760 void snapshotFreeList(TracedValue&) override; | |
| 761 #endif | |
| 762 | |
| 763 Address allocateObject(size_t allocationSize, size_t gcInfoIndex); | |
| 764 | |
| 765 void freePage(NormalPage*); | |
| 766 | |
| 767 bool coalesce(); | |
| 768 void promptlyFreeObject(HeapObjectHeader*); | |
| 769 bool expandObject(HeapObjectHeader*, size_t); | |
| 770 bool shrinkObject(HeapObjectHeader*, size_t); | |
| 771 void decreasePromptlyFreedSize(size_t size) { m_promptlyFreedSize -= size; } | |
| 772 | |
| 773 private: | |
| 774 void allocatePage(); | |
| 775 Address lazySweepPages(size_t, size_t gcInfoIndex) override; | |
| 776 Address outOfLineAllocate(size_t allocationSize, size_t gcInfoIndex); | |
| 777 Address currentAllocationPoint() const { return m_currentAllocationPoint; } | |
| 778 size_t remainingAllocationSize() const { return m_remainingAllocationSize; } | |
| 779 bool hasCurrentAllocationArea() const { return currentAllocationPoint() && r
emainingAllocationSize(); } | |
| 780 void setAllocationPoint(Address, size_t); | |
| 781 void updateRemainingAllocationSize(); | |
| 782 Address allocateFromFreeList(size_t, size_t gcInfoIndex); | |
| 783 | |
| 784 FreeList m_freeList; | |
| 785 Address m_currentAllocationPoint; | |
| 786 size_t m_remainingAllocationSize; | |
| 787 size_t m_lastRemainingAllocationSize; | |
| 788 | |
| 789 // The size of promptly freed objects in the heap. | |
| 790 size_t m_promptlyFreedSize; | |
| 791 | |
| 792 #if ENABLE(GC_PROFILING) | |
| 793 size_t m_cumulativeAllocationSize; | |
| 794 size_t m_allocationCount; | |
| 795 size_t m_inlineAllocationCount; | |
| 796 #endif | |
| 797 }; | |
| 798 | |
| 799 class LargeObjectHeap final : public BaseHeap { | |
| 800 public: | |
| 801 LargeObjectHeap(ThreadState*, int); | |
| 802 Address allocateLargeObjectPage(size_t, size_t gcInfoIndex); | |
| 803 void freeLargeObjectPage(LargeObjectPage*); | |
| 804 #if ENABLE(ASSERT) | |
| 805 bool isConsistentForGC() override { return true; } | |
| 806 #endif | |
| 807 private: | |
| 808 Address doAllocateLargeObjectPage(size_t, size_t gcInfoIndex); | |
| 809 Address lazySweepPages(size_t, size_t gcInfoIndex) override; | |
| 810 }; | |
| 811 | |
| 812 // Mask an address down to the enclosing oilpan heap base page. All oilpan heap | |
| 813 // pages are aligned at blinkPageBase plus the size of a guard size. | |
| 814 // FIXME: Remove PLATFORM_EXPORT once we get a proper public interface to our | |
| 815 // typed heaps. This is only exported to enable tests in HeapTest.cpp. | |
| 816 PLATFORM_EXPORT inline BasePage* pageFromObject(const void* object) | |
| 817 { | |
| 818 Address address = reinterpret_cast<Address>(const_cast<void*>(object)); | |
| 819 BasePage* page = reinterpret_cast<BasePage*>(blinkPageAddress(address) + bli
nkGuardPageSize); | |
| 820 ASSERT(page->contains(address)); | |
| 821 return page; | |
| 822 } | |
| 823 | |
| 824 template<typename T, bool = NeedsAdjustAndMark<T>::value> class ObjectAliveTrait
; | 46 template<typename T, bool = NeedsAdjustAndMark<T>::value> class ObjectAliveTrait
; |
| 825 | 47 |
| 826 template<typename T> | 48 template<typename T> |
| 827 class ObjectAliveTrait<T, false> { | 49 class ObjectAliveTrait<T, false> { |
| 828 public: | 50 public: |
| 829 static bool isHeapObjectAlive(T* object) | 51 static bool isHeapObjectAlive(T* object) |
| 830 { | 52 { |
| 831 static_assert(sizeof(T), "T must be fully defined"); | 53 static_assert(sizeof(T), "T must be fully defined"); |
| 832 return HeapObjectHeader::fromPayload(object)->isMarked(); | 54 return HeapObjectHeader::fromPayload(object)->isMarked(); |
| 833 } | 55 } |
| (...skipping 394 matching lines...) Expand 10 before | Expand all | Expand 10 after Loading... |
| 1228 #else | 450 #else |
| 1229 #define EAGERLY_FINALIZE() typedef int IsEagerlyFinalizedMarker | 451 #define EAGERLY_FINALIZE() typedef int IsEagerlyFinalizedMarker |
| 1230 #endif | 452 #endif |
| 1231 | 453 |
| 1232 #if !ENABLE(OILPAN) && ENABLE(LAZY_SWEEPING) | 454 #if !ENABLE(OILPAN) && ENABLE(LAZY_SWEEPING) |
| 1233 #define EAGERLY_FINALIZE_WILL_BE_REMOVED() EAGERLY_FINALIZE() | 455 #define EAGERLY_FINALIZE_WILL_BE_REMOVED() EAGERLY_FINALIZE() |
| 1234 #else | 456 #else |
| 1235 #define EAGERLY_FINALIZE_WILL_BE_REMOVED() | 457 #define EAGERLY_FINALIZE_WILL_BE_REMOVED() |
| 1236 #endif | 458 #endif |
| 1237 | 459 |
| 1238 NO_SANITIZE_ADDRESS inline | |
| 1239 size_t HeapObjectHeader::size() const | |
| 1240 { | |
| 1241 size_t result = m_encoded & headerSizeMask; | |
| 1242 // Large objects should not refer to header->size(). | |
| 1243 // The actual size of a large object is stored in | |
| 1244 // LargeObjectPage::m_payloadSize. | |
| 1245 ASSERT(result != largeObjectSizeInHeader); | |
| 1246 ASSERT(!pageFromObject(this)->isLargeObjectPage()); | |
| 1247 return result; | |
| 1248 } | |
| 1249 | |
| 1250 #if ENABLE(ASSERT) | |
| 1251 NO_SANITIZE_ADDRESS inline | |
| 1252 bool HeapObjectHeader::checkHeader() const | |
| 1253 { | |
| 1254 return !pageFromObject(this)->orphaned() && m_magic == magic; | |
| 1255 } | |
| 1256 #endif | |
| 1257 | |
| 1258 inline Address HeapObjectHeader::payload() | |
| 1259 { | |
| 1260 return reinterpret_cast<Address>(this) + sizeof(HeapObjectHeader); | |
| 1261 } | |
| 1262 | |
| 1263 inline Address HeapObjectHeader::payloadEnd() | |
| 1264 { | |
| 1265 return reinterpret_cast<Address>(this) + size(); | |
| 1266 } | |
| 1267 | |
| 1268 NO_SANITIZE_ADDRESS inline | |
| 1269 size_t HeapObjectHeader::payloadSize() | |
| 1270 { | |
| 1271 size_t size = m_encoded & headerSizeMask; | |
| 1272 if (UNLIKELY(size == largeObjectSizeInHeader)) { | |
| 1273 ASSERT(pageFromObject(this)->isLargeObjectPage()); | |
| 1274 return static_cast<LargeObjectPage*>(pageFromObject(this))->payloadSize(
); | |
| 1275 } | |
| 1276 ASSERT(!pageFromObject(this)->isLargeObjectPage()); | |
| 1277 return size - sizeof(HeapObjectHeader); | |
| 1278 } | |
| 1279 | |
| 1280 inline HeapObjectHeader* HeapObjectHeader::fromPayload(const void* payload) | |
| 1281 { | |
| 1282 Address addr = reinterpret_cast<Address>(const_cast<void*>(payload)); | |
| 1283 HeapObjectHeader* header = reinterpret_cast<HeapObjectHeader*>(addr - sizeof
(HeapObjectHeader)); | |
| 1284 ASSERT(header->checkHeader()); | |
| 1285 return header; | |
| 1286 } | |
| 1287 | |
| 1288 NO_SANITIZE_ADDRESS inline | |
| 1289 bool HeapObjectHeader::isMarked() const | |
| 1290 { | |
| 1291 ASSERT(checkHeader()); | |
| 1292 return m_encoded & headerMarkBitMask; | |
| 1293 } | |
| 1294 | |
| 1295 NO_SANITIZE_ADDRESS inline | |
| 1296 void HeapObjectHeader::mark() | |
| 1297 { | |
| 1298 ASSERT(checkHeader()); | |
| 1299 ASSERT(!isMarked()); | |
| 1300 m_encoded = m_encoded | headerMarkBitMask; | |
| 1301 } | |
| 1302 | |
| 1303 NO_SANITIZE_ADDRESS inline | |
| 1304 void HeapObjectHeader::unmark() | |
| 1305 { | |
| 1306 ASSERT(checkHeader()); | |
| 1307 ASSERT(isMarked()); | |
| 1308 m_encoded &= ~headerMarkBitMask; | |
| 1309 } | |
| 1310 | |
| 1311 NO_SANITIZE_ADDRESS inline | |
| 1312 bool HeapObjectHeader::isDead() const | |
| 1313 { | |
| 1314 ASSERT(checkHeader()); | |
| 1315 return m_encoded & headerDeadBitMask; | |
| 1316 } | |
| 1317 | |
| 1318 NO_SANITIZE_ADDRESS inline | |
| 1319 void HeapObjectHeader::markDead() | |
| 1320 { | |
| 1321 ASSERT(checkHeader()); | |
| 1322 ASSERT(!isMarked()); | |
| 1323 m_encoded |= headerDeadBitMask; | |
| 1324 } | |
| 1325 | |
| 1326 inline Address NormalPageHeap::allocateObject(size_t allocationSize, size_t gcIn
foIndex) | |
| 1327 { | |
| 1328 #if ENABLE(GC_PROFILING) | |
| 1329 m_cumulativeAllocationSize += allocationSize; | |
| 1330 ++m_allocationCount; | |
| 1331 #endif | |
| 1332 | |
| 1333 if (LIKELY(allocationSize <= m_remainingAllocationSize)) { | |
| 1334 #if ENABLE(GC_PROFILING) | |
| 1335 ++m_inlineAllocationCount; | |
| 1336 #endif | |
| 1337 Address headerAddress = m_currentAllocationPoint; | |
| 1338 m_currentAllocationPoint += allocationSize; | |
| 1339 m_remainingAllocationSize -= allocationSize; | |
| 1340 ASSERT(gcInfoIndex > 0); | |
| 1341 new (NotNull, headerAddress) HeapObjectHeader(allocationSize, gcInfoInde
x); | |
| 1342 Address result = headerAddress + sizeof(HeapObjectHeader); | |
| 1343 ASSERT(!(reinterpret_cast<uintptr_t>(result) & allocationMask)); | |
| 1344 | |
| 1345 SET_MEMORY_ACCESSIBLE(result, allocationSize - sizeof(HeapObjectHeader))
; | |
| 1346 ASSERT(findPageFromAddress(headerAddress + allocationSize - 1)); | |
| 1347 return result; | |
| 1348 } | |
| 1349 return outOfLineAllocate(allocationSize, gcInfoIndex); | |
| 1350 } | |
| 1351 | |
| 1352 template<typename Derived> | |
| 1353 template<typename T> | |
| 1354 void VisitorHelper<Derived>::handleWeakCell(Visitor* self, void* object) | |
| 1355 { | |
| 1356 T** cell = reinterpret_cast<T**>(object); | |
| 1357 if (*cell && !ObjectAliveTrait<T>::isHeapObjectAlive(*cell)) | |
| 1358 *cell = nullptr; | |
| 1359 } | |
| 1360 | |
| 1361 inline Address Heap::allocateOnHeapIndex(ThreadState* state, size_t size, int he
apIndex, size_t gcInfoIndex) | 460 inline Address Heap::allocateOnHeapIndex(ThreadState* state, size_t size, int he
apIndex, size_t gcInfoIndex) |
| 1362 { | 461 { |
| 1363 ASSERT(state->isAllocationAllowed()); | 462 ASSERT(state->isAllocationAllowed()); |
| 1364 ASSERT(heapIndex != ThreadState::LargeObjectHeapIndex); | 463 ASSERT(heapIndex != ThreadState::LargeObjectHeapIndex); |
| 1365 NormalPageHeap* heap = static_cast<NormalPageHeap*>(state->heap(heapIndex)); | 464 NormalPageHeap* heap = static_cast<NormalPageHeap*>(state->heap(heapIndex)); |
| 1366 return heap->allocateObject(allocationSizeFromSize(size), gcInfoIndex); | 465 return heap->allocateObject(allocationSizeFromSize(size), gcInfoIndex); |
| 1367 } | 466 } |
| 1368 | 467 |
| 1369 template<typename T> | 468 template<typename T> |
| 1370 Address Heap::allocate(size_t size, bool eagerlySweep) | 469 Address Heap::allocate(size_t size, bool eagerlySweep) |
| (...skipping 28 matching lines...) Expand all Loading... |
| 1399 ASSERT(!Heap::gcInfo(previousHeader->gcInfoIndex())->hasFinalizer()); | 498 ASSERT(!Heap::gcInfo(previousHeader->gcInfoIndex())->hasFinalizer()); |
| 1400 ASSERT(previousHeader->gcInfoIndex() == GCInfoTrait<T>::index()); | 499 ASSERT(previousHeader->gcInfoIndex() == GCInfoTrait<T>::index()); |
| 1401 Address address = Heap::allocateOnHeapIndex(state, size, heapIndex, GCInfoTr
ait<T>::index()); | 500 Address address = Heap::allocateOnHeapIndex(state, size, heapIndex, GCInfoTr
ait<T>::index()); |
| 1402 size_t copySize = previousHeader->payloadSize(); | 501 size_t copySize = previousHeader->payloadSize(); |
| 1403 if (copySize > size) | 502 if (copySize > size) |
| 1404 copySize = size; | 503 copySize = size; |
| 1405 memcpy(address, previous, copySize); | 504 memcpy(address, previous, copySize); |
| 1406 return address; | 505 return address; |
| 1407 } | 506 } |
| 1408 | 507 |
| 508 template<typename Derived> |
| 509 template<typename T> |
| 510 void VisitorHelper<Derived>::handleWeakCell(Visitor* self, void* object) |
| 511 { |
| 512 T** cell = reinterpret_cast<T**>(object); |
| 513 if (*cell && !ObjectAliveTrait<T>::isHeapObjectAlive(*cell)) |
| 514 *cell = nullptr; |
| 515 } |
| 516 |
| 1409 } // namespace blink | 517 } // namespace blink |
| 1410 | 518 |
| 1411 #endif // Heap_h | 519 #endif // Heap_h |
| OLD | NEW |