Multi-page growing and shrinking new-space

src/mark-compact.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 105 matching lines @@
 static void VerifyMarking(NewSpace* space) {
   Address end = space->top();
   NewSpacePageIterator it(space->bottom(), end);
   // The bottom position is at the start of its page. Allows us to use
   // page->body() as start of range on all pages.
   ASSERT_EQ(space->bottom(),
             NewSpacePage::FromAddress(space->bottom())->body());
   while (it.has_next()) {
     NewSpacePage* page = it.next();
     Address limit = it.has_next() ? page->body_limit() : end;
+    ASSERT(limit == end || !page->Contains(end));
     VerifyMarking(page->body(), limit);
   }
 }
 
 
 static void VerifyMarking(PagedSpace* space) {
   PageIterator it(space);
 
   while (it.has_next()) {
     VerifyMarking(it.next());
@@ skipping 50 matching lines @@
 #ifdef DEBUG
 static void VerifyMarkbitsAreClean(PagedSpace* space) {
   PageIterator it(space);
 
   while (it.has_next()) {
     Page* p = it.next();
     ASSERT(p->markbits()->IsClean());
   }
 }
 
+static void VerifyMarkbitsAreClean(NewSpace* space) {
+  NewSpacePageIterator it(space->ToSpaceLow(), space->ToSpaceHigh());
+
+  while (it.has_next()) {
+    NewSpacePage* p = it.next();
+    ASSERT(p->markbits()->IsClean());
+  }
+}
+
 static void VerifyMarkbitsAreClean() {
   VerifyMarkbitsAreClean(HEAP->old_pointer_space());
   VerifyMarkbitsAreClean(HEAP->old_data_space());
   VerifyMarkbitsAreClean(HEAP->code_space());
   VerifyMarkbitsAreClean(HEAP->cell_space());
   VerifyMarkbitsAreClean(HEAP->map_space());
-  ASSERT(HEAP->new_space()->ActivePage()->markbits()->IsClean());
+  VerifyMarkbitsAreClean(HEAP->new_space());
 }
 #endif
 
 
 static void ClearMarkbits(PagedSpace* space) {
   PageIterator it(space);
 
   while (it.has_next()) {
     Page* p = it.next();
     p->markbits()->Clear();
   }
 }
 
 
+static void ClearMarkbits(NewSpace* space) {
+  NewSpacePageIterator it(space->ToSpaceLow(), space->ToSpaceHigh());
+
+  while (it.has_next()) {
+    NewSpacePage* p = it.next();
+    p->markbits()->Clear();
+  }
+}
+
+
 static void ClearMarkbits() {
   // TODO(gc): Clean the mark bits while sweeping.
-  ClearMarkbits(HEAP->code_space());
-  ClearMarkbits(HEAP->map_space());
-  ClearMarkbits(HEAP->old_pointer_space());
-  ClearMarkbits(HEAP->old_data_space());
-  ClearMarkbits(HEAP->cell_space());
-  HEAP->new_space()->ActivePage()->markbits()->Clear();
+  Heap* heap = HEAP;
+  ClearMarkbits(heap->code_space());
+  ClearMarkbits(heap->map_space());
+  ClearMarkbits(heap->old_pointer_space());
+  ClearMarkbits(heap->old_data_space());
+  ClearMarkbits(heap->cell_space());
+  ClearMarkbits(heap->new_space());
 }
 
 
 void Marking::TransferMark(Address old_start, Address new_start) {
   if (old_start == new_start) return;
 
   MarkBit new_mark_bit = MarkBitFrom(new_start);
 
   if (heap_->incremental_marking()->IsMarking()) {
     MarkBit old_mark_bit = MarkBitFrom(old_start);
@@ skipping 2562 matching lines @@
 }
 
 
 void MarkCompactCollector::Initialize() {
   StaticPointersToNewGenUpdatingVisitor::Initialize();
   StaticMarkingVisitor::Initialize();
 }
 
 
 } }  // namespace v8::internal