Experimental parser: merge to r19637

src/spaces.h

 // Copyright 2011 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 85 matching lines @@
 
 // Some assertion macros used in the debugging mode.
 
 #define ASSERT_PAGE_ALIGNED(address)                                           \
   ASSERT((OffsetFrom(address) & Page::kPageAlignmentMask) == 0)
 
 #define ASSERT_OBJECT_ALIGNED(address)                                         \
   ASSERT((OffsetFrom(address) & kObjectAlignmentMask) == 0)
 
 #define ASSERT_OBJECT_SIZE(size)                                               \
-  ASSERT((0 < size) && (size <= Page::kMaxNonCodeHeapObjectSize))
+  ASSERT((0 < size) && (size <= Page::kMaxRegularHeapObjectSize))
 
 #define ASSERT_PAGE_OFFSET(offset)                                             \
   ASSERT((Page::kObjectStartOffset <= offset)                                  \
       && (offset <= Page::kPageSize))
 
 #define ASSERT_MAP_PAGE_INDEX(index)                                           \
   ASSERT((0 <= index) && (index <= MapSpace::kMaxMapPageIndex))
 
 
 class PagedSpace;
@@ skipping 189 matching lines @@
     return reinterpret_cast<MemoryChunk*>(OffsetFrom(a) & ~kAlignmentMask);
   }
 
   // Only works for addresses in pointer spaces, not data or code spaces.
   static inline MemoryChunk* FromAnyPointerAddress(Heap* heap, Address addr);
 
   Address address() { return reinterpret_cast<Address>(this); }
 
   bool is_valid() { return address() != NULL; }
 
-  MemoryChunk* next_chunk() const { return next_chunk_; }
-  MemoryChunk* prev_chunk() const { return prev_chunk_; }
+  MemoryChunk* next_chunk() const {
+    return reinterpret_cast<MemoryChunk*>(Acquire_Load(&next_chunk_));
+  }
 
-  void set_next_chunk(MemoryChunk* next) { next_chunk_ = next; }
-  void set_prev_chunk(MemoryChunk* prev) { prev_chunk_ = prev; }
+  MemoryChunk* prev_chunk() const {
+    return reinterpret_cast<MemoryChunk*>(Acquire_Load(&prev_chunk_));
+  }
+
+  void set_next_chunk(MemoryChunk* next) {
+    Release_Store(&next_chunk_, reinterpret_cast<AtomicWord>(next));
+  }
+
+  void set_prev_chunk(MemoryChunk* prev) {
+    Release_Store(&prev_chunk_, reinterpret_cast<AtomicWord>(prev));
+  }
 
   Space* owner() const {
     if ((reinterpret_cast<intptr_t>(owner_) & kFailureTagMask) ==
         kFailureTag) {
       return reinterpret_cast<Space*>(reinterpret_cast<intptr_t>(owner_) -
                                       kFailureTag);
     } else {
       return NULL;
     }
   }
@@ skipping 119 matching lines @@
   // Set or clear multiple flags at a time. The flags in the mask
   // are set to the value in "flags", the rest retain the current value
   // in flags_.
   void SetFlags(intptr_t flags, intptr_t mask) {
     flags_ = (flags_ & ~mask) | (flags & mask);
   }
 
   // Return all current flags.
   intptr_t GetFlags() { return flags_; }
 
-  intptr_t parallel_sweeping() const {
-    return parallel_sweeping_;
+
+  // PARALLEL_SWEEPING_PENDING - This page is ready for parallel sweeping.
+  // PARALLEL_SWEEPING_IN_PROGRESS - This page is currently swept or was
+  // swept by a sweeper thread.
+  // PARALLEL_SWEEPING_DONE - The page state when sweeping is complete or
+  // sweeping must not be performed on that page.
+  enum ParallelSweepingState {
+    PARALLEL_SWEEPING_DONE,
+    PARALLEL_SWEEPING_IN_PROGRESS,
+    PARALLEL_SWEEPING_PENDING
+  };
+
+  ParallelSweepingState parallel_sweeping() {
+    return static_cast<ParallelSweepingState>(
+        NoBarrier_Load(&parallel_sweeping_));
   }
 
-  void set_parallel_sweeping(intptr_t state) {
-    parallel_sweeping_ = state;
+  void set_parallel_sweeping(ParallelSweepingState state) {
+    NoBarrier_Store(&parallel_sweeping_, state);
   }
 
   bool TryParallelSweeping() {
-    return NoBarrier_CompareAndSwap(&parallel_sweeping_, 1, 0) == 1;
+    return NoBarrier_CompareAndSwap(&parallel_sweeping_,
+                                    PARALLEL_SWEEPING_PENDING,
+                                    PARALLEL_SWEEPING_IN_PROGRESS) ==
+                                        PARALLEL_SWEEPING_PENDING;
   }
 
   // Manage live byte count (count of bytes known to be live,
   // because they are marked black).
   void ResetLiveBytes() {
     if (FLAG_gc_verbose) {
       PrintF("ResetLiveBytes:%p:%x->0\n",
              static_cast<void*>(this), live_byte_count_);
     }
     live_byte_count_ = 0;
@@ skipping 49 matching lines @@
     MemoryChunk::FromAddress(address)->IncrementLiveBytes(by);
   }
 
   static void IncrementLiveBytesFromMutator(Address address, int by);
 
   static const intptr_t kAlignment =
       (static_cast<uintptr_t>(1) << kPageSizeBits);
 
   static const intptr_t kAlignmentMask = kAlignment - 1;
 
-  static const intptr_t kSizeOffset = kPointerSize + kPointerSize;
+  static const intptr_t kSizeOffset = 0;
 
   static const intptr_t kLiveBytesOffset =
      kSizeOffset + kPointerSize + kPointerSize + kPointerSize +
      kPointerSize + kPointerSize +
      kPointerSize + kPointerSize + kPointerSize + kIntSize;
 
   static const size_t kSlotsBufferOffset = kLiveBytesOffset + kIntSize;
 
   static const size_t kWriteBarrierCounterOffset =
       kSlotsBufferOffset + kPointerSize + kPointerSize;
 
   static const size_t kHeaderSize = kWriteBarrierCounterOffset + kPointerSize +
                                     kIntSize + kIntSize + kPointerSize +
-                                    5 * kPointerSize;
+                                    5 * kPointerSize +
+                                    kPointerSize + kPointerSize;
 
   static const int kBodyOffset =
       CODE_POINTER_ALIGN(kHeaderSize + Bitmap::kSize);
 
   // The start offset of the object area in a page. Aligned to both maps and
   // code alignment to be suitable for both.  Also aligned to 32 words because
   // the marking bitmap is arranged in 32 bit chunks.
   static const int kObjectStartAlignment = 32 * kPointerSize;
   static const int kObjectStartOffset = kBodyOffset - 1 +
       (kObjectStartAlignment - (kBodyOffset - 1) % kObjectStartAlignment);
@@ skipping 51 matching lines @@
 
   inline Address MarkbitIndexToAddress(uint32_t index) {
     return this->address() + (index << kPointerSizeLog2);
   }
 
   void InsertAfter(MemoryChunk* other);
   void Unlink();
 
   inline Heap* heap() { return heap_; }
 
-  static const int kFlagsOffset = kPointerSize * 3;
+  static const int kFlagsOffset = kPointerSize;
 
   bool IsEvacuationCandidate() { return IsFlagSet(EVACUATION_CANDIDATE); }
 
   bool ShouldSkipEvacuationSlotRecording() {
     return (flags_ & kSkipEvacuationSlotsRecordingMask) != 0;
   }
 
   inline SkipList* skip_list() {
     return skip_list_;
   }
@@ skipping 28 matching lines @@
   bool CommitArea(size_t requested);
 
   // Approximate amount of physical memory committed for this chunk.
   size_t CommittedPhysicalMemory() {
     return high_water_mark_;
   }
 
   static inline void UpdateHighWaterMark(Address mark);
 
  protected:
-  MemoryChunk* next_chunk_;
-  MemoryChunk* prev_chunk_;
   size_t size_;
   intptr_t flags_;
 
   // Start and end of allocatable memory on this chunk.
   Address area_start_;
   Address area_end_;
 
   // If the chunk needs to remember its memory reservation, it is stored here.
   VirtualMemory reservation_;
   // The identity of the owning space.  This is tagged as a failure pointer, but
   // no failure can be in an object, so this can be distinguished from any entry
   // in a fixed array.
   Address owner_;
   Heap* heap_;
   // Used by the store buffer to keep track of which pages to mark scan-on-
   // scavenge.
   int store_buffer_counter_;
   // Count of bytes marked black on page.
   int live_byte_count_;
   SlotsBuffer* slots_buffer_;
   SkipList* skip_list_;
   intptr_t write_barrier_counter_;
   // Used by the incremental marker to keep track of the scanning progress in
   // large objects that have a progress bar and are scanned in increments.
   int progress_bar_;
   // Assuming the initial allocation on a page is sequential,
   // count highest number of bytes ever allocated on the page.
   int high_water_mark_;
 
-  intptr_t parallel_sweeping_;
+  AtomicWord parallel_sweeping_;
 
   // PagedSpace free-list statistics.
   intptr_t available_in_small_free_list_;
   intptr_t available_in_medium_free_list_;
   intptr_t available_in_large_free_list_;
   intptr_t available_in_huge_free_list_;
   intptr_t non_available_small_blocks_;
 
   static MemoryChunk* Initialize(Heap* heap,
                                  Address base,
                                  size_t size,
                                  Address area_start,
                                  Address area_end,
                                  Executability executable,
                                  Space* owner);
 
+ private:
+  // next_chunk_ holds a pointer of type MemoryChunk
+  AtomicWord next_chunk_;
+  // prev_chunk_ holds a pointer of type MemoryChunk
+  AtomicWord prev_chunk_;
+
   friend class MemoryAllocator;
 };
 
 
 STATIC_CHECK(sizeof(MemoryChunk) <= MemoryChunk::kHeaderSize);
 
 
 // -----------------------------------------------------------------------------
 // A page is a memory chunk of a size 1MB. Large object pages may be larger.
 //
@@ skipping 40 matching lines @@
   Address OffsetToAddress(int offset) {
     ASSERT_PAGE_OFFSET(offset);
     return address() + offset;
   }
 
   // ---------------------------------------------------------------------
 
   // Page size in bytes.  This must be a multiple of the OS page size.
   static const int kPageSize = 1 << kPageSizeBits;
 
-  // Object area size in bytes.
-  static const int kNonCodeObjectAreaSize = kPageSize - kObjectStartOffset;
-
   // Maximum object size that fits in a page. Objects larger than that size
   // are allocated in large object space and are never moved in memory. This
   // also applies to new space allocation, since objects are never migrated
   // from new space to large object space.  Takes double alignment into account.
-  static const int kMaxNonCodeHeapObjectSize =
-      kNonCodeObjectAreaSize - kPointerSize;
+  static const int kMaxRegularHeapObjectSize = kPageSize - kObjectStartOffset;
 
   // Page size mask.
   static const intptr_t kPageAlignmentMask = (1 << kPageSizeBits) - 1;
 
   inline void ClearGCFields();
 
   static inline Page* Initialize(Heap* heap,
                                  MemoryChunk* chunk,
                                  Executability executable,
                                  PagedSpace* owner);
@@ skipping 272 matching lines @@
   intptr_t AvailableExecutable() {
     if (capacity_executable_ < size_executable_) return 0;
     return capacity_executable_ - size_executable_;
   }
 
   // Returns allocated executable spaces in bytes.
   intptr_t SizeExecutable() { return size_executable_; }
 
   // Returns maximum available bytes that the old space can have.
   intptr_t MaxAvailable() {
-    return (Available() / Page::kPageSize) * Page::kMaxNonCodeHeapObjectSize;
+    return (Available() / Page::kPageSize) * Page::kMaxRegularHeapObjectSize;
   }
 
   // Returns an indication of whether a pointer is in a space that has
   // been allocated by this MemoryAllocator.
   V8_INLINE bool IsOutsideAllocatedSpace(const void* address) const {
     return address < lowest_ever_allocated_ ||
         address >= highest_ever_allocated_;
   }
 
 #ifdef DEBUG
@@ skipping 406 matching lines @@
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(FreeListNode);
 };
 
 
 // The free list category holds a pointer to the top element and a pointer to
 // the end element of the linked list of free memory blocks.
 class FreeListCategory {
  public:
   FreeListCategory() :
-      top_(NULL),
+      top_(0),
       end_(NULL),
       available_(0) {}
 
   intptr_t Concatenate(FreeListCategory* category);
 
   void Reset();
 
   void Free(FreeListNode* node, int size_in_bytes);
 
   FreeListNode* PickNodeFromList(int *node_size);
   FreeListNode* PickNodeFromList(int size_in_bytes, int *node_size);
 
   intptr_t EvictFreeListItemsInList(Page* p);
+  bool ContainsPageFreeListItemsInList(Page* p);
 
   void RepairFreeList(Heap* heap);
 
-  FreeListNode** GetTopAddress() { return &top_; }
-  FreeListNode* top() const { return top_; }
-  void set_top(FreeListNode* top) { top_ = top; }
+  FreeListNode* top() const {
+    return reinterpret_cast<FreeListNode*>(NoBarrier_Load(&top_));
+  }
+
+  void set_top(FreeListNode* top) {
+    NoBarrier_Store(&top_, reinterpret_cast<AtomicWord>(top));
+  }
 
   FreeListNode** GetEndAddress() { return &end_; }
   FreeListNode* end() const { return end_; }
   void set_end(FreeListNode* end) { end_ = end; }
 
   int* GetAvailableAddress() { return &available_; }
   int available() const { return available_; }
   void set_available(int available) { available_ = available; }
 
   Mutex* mutex() { return &mutex_; }
 
+  bool IsEmpty() {
+    return top() == 0;
+  }
+
 #ifdef DEBUG
   intptr_t SumFreeList();
   int FreeListLength();
 #endif
 
  private:
-  FreeListNode* top_;
+  // top_ points to the top FreeListNode* in the free list category.
+  AtomicWord top_;
   FreeListNode* end_;
   Mutex mutex_;
 
   // Total available bytes in all blocks of this free list category.
   int available_;
 };
 
 
 // The free list for the old space.  The free list is organized in such a way
 // as to encourage objects allocated around the same time to be near each
@@ skipping 11 matching lines @@
 //     limit when the object we need to allocate is 1-31 words in size.  These
 //     spaces are called small.
 // 256-2047 words: There is a list of spaces this large.  It is used for top and
 //     limit when the object we need to allocate is 32-255 words in size.  These
 //     spaces are called medium.
 // 1048-16383 words: There is a list of spaces this large.  It is used for top
 //     and limit when the object we need to allocate is 256-2047 words in size.
 //     These spaces are call large.
 // At least 16384 words.  This list is for objects of 2048 words or larger.
 //     Empty pages are added to this list.  These spaces are called huge.
-class FreeList BASE_EMBEDDED {
+class FreeList {
  public:
   explicit FreeList(PagedSpace* owner);
 
   intptr_t Concatenate(FreeList* free_list);
 
   // Clear the free list.
   void Reset();
 
   // Return the number of bytes available on the free list.
   intptr_t available() {
     return small_list_.available() + medium_list_.available() +
            large_list_.available() + huge_list_.available();
   }
 
   // Place a node on the free list.  The block of size 'size_in_bytes'
   // starting at 'start' is placed on the free list.  The return value is the
   // number of bytes that have been lost due to internal fragmentation by
   // freeing the block.  Bookkeeping information will be written to the block,
   // i.e., its contents will be destroyed.  The start address should be word
   // aligned, and the size should be a non-zero multiple of the word size.
   int Free(Address start, int size_in_bytes);
 
   // Allocate a block of size 'size_in_bytes' from the free list.  The block
   // is unitialized.  A failure is returned if no block is available.  The
   // number of bytes lost to fragmentation is returned in the output parameter
   // 'wasted_bytes'.  The size should be a non-zero multiple of the word size.
   MUST_USE_RESULT HeapObject* Allocate(int size_in_bytes);
 
+  bool IsEmpty() {
+    return small_list_.IsEmpty() && medium_list_.IsEmpty() &&
+           large_list_.IsEmpty() && huge_list_.IsEmpty();
+  }
+
 #ifdef DEBUG
   void Zap();
   intptr_t SumFreeLists();
   bool IsVeryLong();
 #endif
 
   // Used after booting the VM.
   void RepairLists(Heap* heap);
 
   intptr_t EvictFreeListItems(Page* p);
+  bool ContainsPageFreeListItems(Page* p);
 
   FreeListCategory* small_list() { return &small_list_; }
   FreeListCategory* medium_list() { return &medium_list_; }
   FreeListCategory* large_list() { return &large_list_; }
   FreeListCategory* huge_list() { return &huge_list_; }
 
  private:
   // The size range of blocks, in bytes.
   static const int kMinBlockSize = 3 * kPointerSize;
-  static const int kMaxBlockSize = Page::kMaxNonCodeHeapObjectSize;
+  static const int kMaxBlockSize = Page::kMaxRegularHeapObjectSize;
 
   FreeListNode* FindNodeFor(int size_in_bytes, int* node_size);
 
   PagedSpace* owner_;
   Heap* heap_;
 
   static const int kSmallListMin = 0x20 * kPointerSize;
   static const int kSmallListMax = 0xff * kPointerSize;
   static const int kMediumListMax = 0x7ff * kPointerSize;
   static const int kLargeListMax = 0x3fff * kPointerSize;
@@ skipping 300 matching lines @@
   bool Expand();
 
   // Generic fast case allocation function that tries linear allocation at the
   // address denoted by top in allocation_info_.
   inline HeapObject* AllocateLinearly(int size_in_bytes);
 
   // Slow path of AllocateRaw.  This function is space-dependent.
   MUST_USE_RESULT virtual HeapObject* SlowAllocateRaw(int size_in_bytes);
 
   friend class PageIterator;
-  friend class SweeperThread;
+  friend class MarkCompactCollector;
 };
 
 
 class NumberAndSizeInfo BASE_EMBEDDED {
  public:
   NumberAndSizeInfo() : number_(0), bytes_(0) {}
 
   int number() const { return number_; }
   void increment_number(int num) { number_ += num; }
 
@@ skipping 36 matching lines @@
 
 class NewSpacePage : public MemoryChunk {
  public:
   // GC related flags copied from from-space to to-space when
   // flipping semispaces.
   static const intptr_t kCopyOnFlipFlagsMask =
     (1 << MemoryChunk::POINTERS_TO_HERE_ARE_INTERESTING) |
     (1 << MemoryChunk::POINTERS_FROM_HERE_ARE_INTERESTING) |
     (1 << MemoryChunk::SCAN_ON_SCAVENGE);
 
-  static const int kAreaSize = Page::kNonCodeObjectAreaSize;
+  static const int kAreaSize = Page::kMaxRegularHeapObjectSize;
 
   inline NewSpacePage* next_page() const {
     return static_cast<NewSpacePage*>(next_chunk());
   }
 
   inline void set_next_page(NewSpacePage* page) {
     set_next_chunk(page);
   }
 
   inline NewSpacePage* prev_page() const {
@@ skipping 31 matching lines @@
     NewSpacePage* page = reinterpret_cast<NewSpacePage*>(page_start);
     return page;
   }
 
   // Find the page for a limit address. A limit address is either an address
   // inside a page, or the address right after the last byte of a page.
   static inline NewSpacePage* FromLimit(Address address_limit) {
     return NewSpacePage::FromAddress(address_limit - 1);
   }
 
+  // Checks if address1 and address2 are on the same new space page.
+  static inline bool OnSamePage(Address address1, Address address2) {
+    return NewSpacePage::FromAddress(address1) ==
+           NewSpacePage::FromAddress(address2);
+  }
+
  private:
   // Create a NewSpacePage object that is only used as anchor
   // for the doubly-linked list of real pages.
   explicit NewSpacePage(SemiSpace* owner) {
     InitializeAsAnchor(owner);
   }
 
   static NewSpacePage* Initialize(Heap* heap,
                                   Address start,
                                   SemiSpace* semi_space);
@@ skipping 374 matching lines @@
   Address top() {
     ASSERT(to_space_.current_page()->ContainsLimit(allocation_info_.top()));
     return allocation_info_.top();
   }
 
   void set_top(Address top) {
     ASSERT(to_space_.current_page()->ContainsLimit(top));
     allocation_info_.set_top(top);
   }
 
+  // Return the address of the allocation pointer limit in the active semispace.
+  Address limit() {
+    ASSERT(to_space_.current_page()->ContainsLimit(allocation_info_.limit()));
+    return allocation_info_.limit();
+  }
+
   // Return the address of the first object in the active semispace.
   Address bottom() { return to_space_.space_start(); }
 
   // Get the age mark of the inactive semispace.
   Address age_mark() { return from_space_.age_mark(); }
   // Set the age mark in the active semispace.
   void set_age_mark(Address mark) { to_space_.set_age_mark(mark); }
 
   // The start address of the space and a bit mask. Anding an address in the
   // new space with the mask will result in the start address.
@@ skipping 194 matching lines @@
       return RoundDown(size, Map::kSize);
     } else {
       return (size / Map::kSize) * Map::kSize;
     }
   }
 
  protected:
   virtual void VerifyObject(HeapObject* obj);
 
  private:
-  static const int kMapsPerPage = Page::kNonCodeObjectAreaSize / Map::kSize;
+  static const int kMapsPerPage = Page::kMaxRegularHeapObjectSize / Map::kSize;
 
   // Do map space compaction if there is a page gap.
   int CompactionThreshold() {
     return kMapsPerPage * (max_map_space_pages_ - 1);
   }
 
   const int max_map_space_pages_;
 
  public:
   TRACK_MEMORY("MapSpace")
@@ skipping 247 matching lines @@
   }
   // Must be small, since an iteration is used for lookup.
   static const int kMaxComments = 64;
 };
 #endif
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_SPACES_H_