Reland "Merge old data and pointer space."

src/heap/heap.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_HEAP_HEAP_H_
 #define V8_HEAP_HEAP_H_
 
 #include <cmath>
 
 #include "src/allocation.h"
@@ skipping 623 matching lines @@
   intptr_t SizeOfObjects();
 
   // Return the starting address and a mask for the new space.  And-masking an
   // address with the mask will result in the start address of the new space
   // for all addresses in either semispace.
   Address NewSpaceStart() { return new_space_.start(); }
   uintptr_t NewSpaceMask() { return new_space_.mask(); }
   Address NewSpaceTop() { return new_space_.top(); }
 
   NewSpace* new_space() { return &new_space_; }
-  OldSpace* old_pointer_space() { return old_pointer_space_; }
-  OldSpace* old_data_space() { return old_data_space_; }
+  OldSpace* old_space() { return old_space_; }
   OldSpace* code_space() { return code_space_; }
   MapSpace* map_space() { return map_space_; }
   CellSpace* cell_space() { return cell_space_; }
   LargeObjectSpace* lo_space() { return lo_space_; }
   PagedSpace* paged_space(int idx) {
     switch (idx) {
-      case OLD_POINTER_SPACE:
-        return old_pointer_space();
-      case OLD_DATA_SPACE:
-        return old_data_space();
+      case OLD_SPACE:
+        return old_space();
       case MAP_SPACE:
         return map_space();
       case CELL_SPACE:
         return cell_space();
       case CODE_SPACE:
         return code_space();
       case NEW_SPACE:
       case LO_SPACE:
         UNREACHABLE();
     }
     return NULL;
   }
 
   bool always_allocate() { return always_allocate_scope_depth_ != 0; }
   Address always_allocate_scope_depth_address() {
     return reinterpret_cast<Address>(&always_allocate_scope_depth_);
   }
 
   Address* NewSpaceAllocationTopAddress() {
     return new_space_.allocation_top_address();
   }
   Address* NewSpaceAllocationLimitAddress() {
     return new_space_.allocation_limit_address();
   }
 
-  Address* OldPointerSpaceAllocationTopAddress() {
-    return old_pointer_space_->allocation_top_address();
+  Address* OldSpaceAllocationTopAddress() {
+    return old_space_->allocation_top_address();
   }
-  Address* OldPointerSpaceAllocationLimitAddress() {
-    return old_pointer_space_->allocation_limit_address();
-  }
-
-  Address* OldDataSpaceAllocationTopAddress() {
-    return old_data_space_->allocation_top_address();
-  }
-  Address* OldDataSpaceAllocationLimitAddress() {
-    return old_data_space_->allocation_limit_address();
+  Address* OldSpaceAllocationLimitAddress() {
+    return old_space_->allocation_limit_address();
   }
 
   // TODO(hpayer): There is still a missmatch between capacity and actual
   // committed memory size.
   bool CanExpandOldGeneration(int size) {
     return (CommittedOldGenerationMemory() + size) < MaxOldGenerationSize();
   }
 
   // Returns a deep copy of the JavaScript object.
   // Properties and elements are copied too.
@@ skipping 210 matching lines @@
                                          Address end,
                                          ObjectSlotCallback callback);
 
   // Returns whether the object resides in new space.
   inline bool InNewSpace(Object* object);
   inline bool InNewSpace(Address address);
   inline bool InNewSpacePage(Address address);
   inline bool InFromSpace(Object* object);
   inline bool InToSpace(Object* object);
 
-  // Returns whether the object resides in old pointer space.
-  inline bool InOldPointerSpace(Address address);
-  inline bool InOldPointerSpace(Object* object);
-
-  // Returns whether the object resides in old data space.
-  inline bool InOldDataSpace(Address address);
-  inline bool InOldDataSpace(Object* object);
+  // Returns whether the object resides in old space.
+  inline bool InOldSpace(Address address);
+  inline bool InOldSpace(Object* object);
 
   // Checks whether an address/object in the heap (including auxiliary
   // area and unused area).
   bool Contains(Address addr);
   bool Contains(HeapObject* value);
 
   // Checks whether an address/object in a space.
   // Currently used by tests, serialization and heap verification only.
   bool InSpace(Address addr, AllocationSpace space);
   bool InSpace(HeapObject* value, AllocationSpace space);
 
-  // Finds out which space an object should get promoted to based on its type.
-  inline OldSpace* TargetSpace(HeapObject* object);
-  static inline AllocationSpace TargetSpaceId(InstanceType type);
-
   // Checks whether the given object is allowed to be migrated from it's
   // current space into the given destination space. Used for debugging.
   inline bool AllowedToBeMigrated(HeapObject* object, AllocationSpace dest);
 
   // Sets the stub_cache_ (only used when expanding the dictionary).
   void public_set_code_stubs(UnseededNumberDictionary* value) {
     roots_[kCodeStubsRootIndex] = value;
   }
 
   // Support for computing object sizes for old objects during GCs. Returns
@@ skipping 625 matching lines @@
   int always_allocate_scope_depth_;
 
   // For keeping track of context disposals.
   int contexts_disposed_;
 
   int global_ic_age_;
 
   int scan_on_scavenge_pages_;
 
   NewSpace new_space_;
-  OldSpace* old_pointer_space_;
-  OldSpace* old_data_space_;
+  OldSpace* old_space_;
   OldSpace* code_space_;
   MapSpace* map_space_;
   CellSpace* cell_space_;
   LargeObjectSpace* lo_space_;
   HeapState gc_state_;
   int gc_post_processing_depth_;
   Address new_space_top_after_last_gc_;
 
   // Returns the amount of external memory registered since last global gc.
   int64_t PromotedExternalMemorySize();
@@ skipping 174 matching lines @@
   // Performs garbage collection
   // Returns whether there is a chance another major GC could
   // collect more garbage.
   bool PerformGarbageCollection(
       GarbageCollector collector,
       const GCCallbackFlags gc_callback_flags = kNoGCCallbackFlags);
 
   inline void UpdateOldSpaceLimits();
 
   // Selects the proper allocation space depending on the given object
-  // size, pretenuring decision, and preferred old-space.
+  // size and pretenuring decision.
   static AllocationSpace SelectSpace(int object_size,
-                                     AllocationSpace preferred_old_space,
                                      PretenureFlag pretenure) {
-    DCHECK(preferred_old_space == OLD_POINTER_SPACE ||
-           preferred_old_space == OLD_DATA_SPACE);
     if (object_size > Page::kMaxRegularHeapObjectSize) return LO_SPACE;
-    return (pretenure == TENURED) ? preferred_old_space : NEW_SPACE;
+    return (pretenure == TENURED) ? OLD_SPACE : NEW_SPACE;
   }
 
   HeapObject* DoubleAlignForDeserialization(HeapObject* object, int size);
 
   // Allocate an uninitialized object.  The memory is non-executable if the
   // hardware and OS allow.  This is the single choke-point for allocations
   // performed by the runtime and should not be bypassed (to extend this to
   // inlined allocations, use the Heap::DisableInlineAllocation() support).
   MUST_USE_RESULT inline AllocationResult AllocateRaw(
       int size_in_bytes, AllocationSpace space, AllocationSpace retry_space);
@@ skipping 382 matching lines @@
 
 
 class HeapStats {
  public:
   static const int kStartMarker = 0xDECADE00;
   static const int kEndMarker = 0xDECADE01;
 
   int* start_marker;                       //  0
   int* new_space_size;                     //  1
   int* new_space_capacity;                 //  2
-  intptr_t* old_pointer_space_size;        //  3
-  intptr_t* old_pointer_space_capacity;    //  4
-  intptr_t* old_data_space_size;           //  5
-  intptr_t* old_data_space_capacity;       //  6
-  intptr_t* code_space_size;               //  7
-  intptr_t* code_space_capacity;           //  8
-  intptr_t* map_space_size;                //  9
-  intptr_t* map_space_capacity;            // 10
-  intptr_t* cell_space_size;               // 11
-  intptr_t* cell_space_capacity;           // 12
-  intptr_t* lo_space_size;                 // 13
-  int* global_handle_count;                // 14
-  int* weak_global_handle_count;           // 15
-  int* pending_global_handle_count;        // 16
-  int* near_death_global_handle_count;     // 17
-  int* free_global_handle_count;           // 18
-  intptr_t* memory_allocator_size;         // 19
-  intptr_t* memory_allocator_capacity;     // 20
-  int* objects_per_type;                   // 21
-  int* size_per_type;                      // 22
-  int* os_error;                           // 23
-  int* end_marker;                         // 24
+  intptr_t* old_space_size;                //  3
+  intptr_t* old_space_capacity;            //  4
+  intptr_t* code_space_size;               //  5
+  intptr_t* code_space_capacity;           //  6
+  intptr_t* map_space_size;                //  7
+  intptr_t* map_space_capacity;            //  8
+  intptr_t* cell_space_size;               //  9
+  intptr_t* cell_space_capacity;           // 10
+  intptr_t* lo_space_size;                 // 11
+  int* global_handle_count;                // 12
+  int* weak_global_handle_count;           // 13
+  int* pending_global_handle_count;        // 14
+  int* near_death_global_handle_count;     // 15
+  int* free_global_handle_count;           // 16
+  intptr_t* memory_allocator_size;         // 17
+  intptr_t* memory_allocator_capacity;     // 18
+  int* objects_per_type;                   // 19
+  int* size_per_type;                      // 20
+  int* os_error;                           // 21
+  int* end_marker;                         // 22
 };
 
 
 class AlwaysAllocateScope {
  public:
   explicit inline AlwaysAllocateScope(Isolate* isolate);
   inline ~AlwaysAllocateScope();
 
  private:
   // Implicitly disable artificial allocation failures.
@@ skipping 38 matching lines @@
  public:
   explicit AllSpaces(Heap* heap) : heap_(heap), counter_(FIRST_SPACE) {}
   Space* next();
 
  private:
   Heap* heap_;
   int counter_;
 };
 
 
-// Space iterator for iterating over all old spaces of the heap: Old pointer
-// space, old data space and code space.  Returns each space in turn, and null
-// when it is done.
+// Space iterator for iterating over all old spaces of the heap: Old space
+// and code space.  Returns each space in turn, and null when it is done.
 class OldSpaces BASE_EMBEDDED {
  public:
-  explicit OldSpaces(Heap* heap) : heap_(heap), counter_(OLD_POINTER_SPACE) {}
+  explicit OldSpaces(Heap* heap) : heap_(heap), counter_(OLD_SPACE) {}
   OldSpace* next();
 
  private:
   Heap* heap_;
   int counter_;
 };
 
 
 // Space iterator for iterating over all the paged spaces of the heap: Map
-// space, old pointer space, old data space, code space and cell space.  Returns
+// space, old space, code space and cell space.  Returns
 // each space in turn, and null when it is done.
 class PagedSpaces BASE_EMBEDDED {
  public:
-  explicit PagedSpaces(Heap* heap) : heap_(heap), counter_(OLD_POINTER_SPACE) {}
+  explicit PagedSpaces(Heap* heap) : heap_(heap), counter_(OLD_SPACE) {}
   PagedSpace* next();
 
  private:
   Heap* heap_;
   int counter_;
 };
 
 
 // Space iterator for iterating over all spaces of the heap.
 // For each space an object iterator is provided. The deallocation of the
@@ skipping 322 matching lines @@
   DisallowHeapAllocation no_allocation;  // i.e. no gc allowed.
 
  private:
   DISALLOW_IMPLICIT_CONSTRUCTORS(PathTracer);
 };
 #endif  // DEBUG
 }
 }  // namespace v8::internal
 
 #endif  // V8_HEAP_HEAP_H_