Centralize code for freeing LargeObjectChunks, fixing an uncommit bug.

src/spaces.cc

 // 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 2710 matching lines @@
       space, kAllocationActionAllocate, size);
 
   LargeObjectChunk* chunk = reinterpret_cast<LargeObjectChunk*>(mem);
   chunk->size_ = size;
   chunk->GetPage()->heap_ = isolate->heap();
   return chunk;
 }
 
 
 void LargeObjectChunk::Free(Executability executable) {
+  size_t guard_size = (executable == EXECUTABLE) ? Page::kPageSize : 0;
+  ObjectSpace space =
+      (executable == EXECUTABLE) ? kObjectSpaceCodeSpace : kObjectSpaceLoSpace;
+  // Do not access instance fields after FreeRawMemory!
+  Address my_address = address();
+  size_t my_size = size();
   Isolate* isolate = GetPage()->heap_->isolate();
-  isolate->memory_allocator()->FreeRawMemory(address(), size(), executable);
+  MemoryAllocator* a = isolate->memory_allocator();
+  a->FreeRawMemory(my_address - guard_size, my_size + guard_size, executable);
+  a->PerformAllocationCallback(space, kAllocationActionFree, my_size);
+  LOG(isolate, DeleteEvent("LargeObjectChunk", my_address));
 }
 
 
 int LargeObjectChunk::ChunkSizeFor(int size_in_bytes) {
   int os_alignment = static_cast<int>(OS::AllocateAlignment());
   if (os_alignment < Page::kPageSize) {
     size_in_bytes += (Page::kPageSize - os_alignment);
   }
   return size_in_bytes + Page::kObjectStartOffset;
 }
@@ skipping 15 matching lines @@
   page_count_ = 0;
   objects_size_ = 0;
   return true;
 }
 
 
 void LargeObjectSpace::TearDown() {
   while (first_chunk_ != NULL) {
     LargeObjectChunk* chunk = first_chunk_;
     first_chunk_ = first_chunk_->next();
-    LOG(heap()->isolate(), DeleteEvent("LargeObjectChunk", chunk->address()));
-    Executability executable = chunk->GetPage()->PageExecutability();
-    ObjectSpace space = kObjectSpaceLoSpace;
-    if (executable == EXECUTABLE) space = kObjectSpaceCodeSpace;
-    size_t size = chunk->size();
-    size_t guard_size = (executable == EXECUTABLE) ? Page::kPageSize : 0;
-    heap()->isolate()->memory_allocator()->FreeRawMemory(
-        chunk->address() - guard_size,
-        size + guard_size,
-        executable);
-    heap()->isolate()->memory_allocator()->PerformAllocationCallback(
-        space, kAllocationActionFree, size);
+    chunk->Free(chunk->GetPage()->PageExecutability());
   }
-
-  size_ = 0;
-  page_count_ = 0;
-  objects_size_ = 0;
+  Setup();

[Vyacheslav Egorov (Chromium), 2011/08/25 15:22:54]

Calling Setup from TearDown is very confusing.

 }
 
 
 MaybeObject* LargeObjectSpace::AllocateRawInternal(int requested_size,
                                                    int object_size,
                                                    Executability executable) {
   ASSERT(0 < object_size && object_size <= requested_size);
 
   // Check if we want to force a GC before growing the old space further.
   // If so, fail the allocation.
@@ skipping 145 matching lines @@
   LargeObjectChunk* previous = NULL;
   LargeObjectChunk* current = first_chunk_;
   while (current != NULL) {
     HeapObject* object = current->GetObject();
     if (object->IsMarked()) {
       object->ClearMark();
       heap()->mark_compact_collector()->tracer()->decrement_marked_count();
       previous = current;
       current = current->next();
     } else {
-      Executability executable = current->GetPage()->PageExecutability();
-      Address chunk_address = current->address();
-      size_t chunk_size = current->size();
-
       // Cut the chunk out from the chunk list.
+      LargeObjectChunk* current_chunk = current;
       current = current->next();
       if (previous == NULL) {
         first_chunk_ = current;
       } else {
         previous->set_next(current);
       }
 
       // Free the chunk.
       heap()->mark_compact_collector()->ReportDeleteIfNeeded(
           object, heap()->isolate());
       LiveObjectList::ProcessNonLive(object);
 
-      size_ -= static_cast<int>(chunk_size);
+      size_ -= static_cast<int>(current_chunk->size());
       objects_size_ -= object->Size();
       page_count_--;
-      ObjectSpace space = kObjectSpaceLoSpace;
-      size_t guard_size = 0;
-      if (executable == EXECUTABLE) {
-        space = kObjectSpaceCodeSpace;
-        guard_size = Page::kPageSize;
-      }
-      heap()->isolate()->memory_allocator()->FreeRawMemory(
-          chunk_address - guard_size,
-          chunk_size + guard_size,
-          executable);
-      heap()->isolate()->memory_allocator()->PerformAllocationCallback(
-          space, kAllocationActionFree, size_);
-      LOG(heap()->isolate(), DeleteEvent("LargeObjectChunk", chunk_address));
+      current_chunk->Free(current_chunk->GetPage()->PageExecutability());
     }
   }
 }
 
 
 bool LargeObjectSpace::Contains(HeapObject* object) {
   Address address = object->address();
   if (heap()->new_space()->Contains(address)) {
     return false;
   }
@@ skipping 96 matching lines @@
   for (HeapObject* obj = obj_it.next(); obj != NULL; obj = obj_it.next()) {
     if (obj->IsCode()) {
       Code* code = Code::cast(obj);
       isolate->code_kind_statistics()[code->kind()] += code->Size();
     }
   }
 }
 #endif  // DEBUG
 
 } }  // namespace v8::internal