Two-page newspace.

src/spaces-inl.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 42 matching lines @@
 
 Page* PageIterator::next() {
   ASSERT(has_next());
   prev_page_ = next_page_;
   next_page_ = next_page_->next_page();
   return prev_page_;
 }
 
 
 // -----------------------------------------------------------------------------
+// NewSpacePageIterator
+
+
+NewSpacePageIterator::NewSpacePageIterator(SemiSpace* space)
+    : prev_page_(&space->anchor_),
+      next_page_(prev_page_->next_page()),
+      last_page_(prev_page_->prev_page()) { }
+
+  NewSpacePageIterator::NewSpacePageIterator(Address start, Address limit)
+    : prev_page_(NewSpacePage::FromAddress(start)->prev_page()),
+      next_page_(NewSpacePage::FromAddress(start)),
+      last_page_(NewSpacePage::FromLimit(limit)) {
+#ifdef DEBUG
+    SemiSpace::ValidateRange(start, limit);
+#endif
+}
+
+
+bool NewSpacePageIterator::has_next() {
+  return prev_page_ != last_page_;
+}
+
+
+NewSpacePage* NewSpacePageIterator::next() {
+  ASSERT(has_next());
+  prev_page_ = next_page_;
+  next_page_ = next_page_->next_page();
+  return prev_page_;
+}
+
+
+// -----------------------------------------------------------------------------
 // HeapObjectIterator
 HeapObject* HeapObjectIterator::FromCurrentPage() {
   while (cur_addr_ != cur_end_) {
     if (cur_addr_ == space_->top() && cur_addr_ != space_->limit()) {
       cur_addr_ = space_->limit();
       continue;
     }
     HeapObject* obj = HeapObject::FromAddress(cur_addr_);
     int obj_size = (size_func_ == NULL) ? obj->Size() : size_func_(obj);
     cur_addr_ += obj_size;
@@ skipping 169 matching lines @@
   }
 
   return Failure::RetryAfterGC(identity());
 }
 
 
 // -----------------------------------------------------------------------------
 // NewSpace
 
 MaybeObject* NewSpace::AllocateRawInternal(int size_in_bytes) {
-  Address new_top = allocation_info_.top + size_in_bytes;
+  Address old_top = allocation_info_.top;
+  Address new_top = old_top + size_in_bytes;
   if (new_top > allocation_info_.limit) {
-    Address high = to_space_.high();
+    Address high = to_space_.page_high();
     if (allocation_info_.limit < high) {
       allocation_info_.limit = Min(
           allocation_info_.limit + inline_alloction_limit_step_,
           high);
       int bytes_allocated = new_top - top_on_previous_step_;
       heap()->incremental_marking()->Step(bytes_allocated);
       top_on_previous_step_ = new_top;
       return AllocateRawInternal(size_in_bytes);
+    } else if (AddFreshPage()) {
+      // Switched to new page. Try allocating again.
+      int bytes_allocated = old_top - top_on_previous_step_;
+      heap()->incremental_marking()->Step(bytes_allocated);
+      top_on_previous_step_ = to_space_.page_low();
+      return AllocateRawInternal(size_in_bytes);
     } else {
       return Failure::RetryAfterGC();
     }
   }
 
   Object* obj = HeapObject::FromAddress(allocation_info_.top);
   allocation_info_.top = new_top;
   ASSERT_SEMISPACE_ALLOCATION_INFO(allocation_info_, to_space_);
 
   return obj;
@@ skipping 26 matching lines @@
 bool FreeListNode::IsFreeListNode(HeapObject* object) {
   // TODO(gc) ISOLATES MERGE
   return object->map() == HEAP->raw_unchecked_free_space_map()
       || object->map() == HEAP->raw_unchecked_one_pointer_filler_map()
       || object->map() == HEAP->raw_unchecked_two_pointer_filler_map();
 }
 
 } }  // namespace v8::internal
 
 #endif  // V8_SPACES_INL_H_