Get rid of ZoneScope completely.

src/zone.cc

 // Copyright 2012 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 55 matching lines @@
   int size_;
 };
 
 
 Zone::Zone(Isolate* isolate)
     : zone_excess_limit_(256 * MB),
       allocation_size_(0),
       segment_bytes_allocated_(0),
       position_(0),
       limit_(0),
-      scope_nesting_(0),
       segment_head_(NULL),
       isolate_(isolate) {
 }
 
 
-ZoneScope::~ZoneScope() {
-  if (ShouldDeleteOnExit()) zone_->DeleteAll();
-  zone_->scope_nesting_--;
+Zone::~Zone() {
+#ifdef DEBUG
+  // Constant byte value used for zapping dead memory in debug mode.
+  static const unsigned char kZapDeadByte = 0xcd;
+#endif
+
+  // Traverse the chained list of segments, zapping
+  // (in debug mode) and freeing every segment
+  Segment* current = segment_head_;
+  while (current != NULL) {
+    Segment* next = current->next();
+    int size = current->size();
+#ifdef DEBUG
+    // Zap the entire current segment (including the header).
+    memset(current, kZapDeadByte, size);
+#endif
+    DeleteSegment(current, size);
+    current = next;
+  }
+
+  // We must clear the position and limit to force
+  // a new segment to be allocated on demand.
+  position_ = limit_ = 0;
+
+  // Update the head segment.
+  segment_head_ = NULL;
 }
 
 
 // Creates a new segment, sets it size, and pushes it to the front
 // of the segment chain. Returns the new segment.
 Segment* Zone::NewSegment(int size) {
   Segment* result = reinterpret_cast<Segment*>(Malloced::New(size));
   adjust_segment_bytes_allocated(size);
   if (result != NULL) {
     result->Initialize(segment_head_, size);
     segment_head_ = result;
   }
   return result;
 }
 
 
 // Deletes the given segment. Does not touch the segment chain.
 void Zone::DeleteSegment(Segment* segment, int size) {
   adjust_segment_bytes_allocated(-size);
   Malloced::Delete(segment);
 }
 
 
-void Zone::DeleteAll() {
-#ifdef DEBUG
-  // Constant byte value used for zapping dead memory in debug mode.
-  static const unsigned char kZapDeadByte = 0xcd;
-#endif
-
-  // Find a segment with a suitable size to keep around.
-  Segment* keep = segment_head_;
-  while (keep != NULL && keep->size() > kMaximumKeptSegmentSize) {
-    keep = keep->next();
-  }
-
-  // Traverse the chained list of segments, zapping (in debug mode)
-  // and freeing every segment except the one we wish to keep.
-  Segment* current = segment_head_;
-  while (current != NULL) {
-    Segment* next = current->next();
-    if (current == keep) {
-      // Unlink the segment we wish to keep from the list.
-      current->clear_next();
-    } else {
-      int size = current->size();
-#ifdef DEBUG
-      // Zap the entire current segment (including the header).
-      memset(current, kZapDeadByte, size);
-#endif
-      DeleteSegment(current, size);
-    }
-    current = next;
-  }
-
-  // If we have found a segment we want to keep, we must recompute the
-  // variables 'position' and 'limit' to prepare for future allocate
-  // attempts. Otherwise, we must clear the position and limit to
-  // force a new segment to be allocated on demand.
-  if (keep != NULL) {
-    Address start = keep->start();
-    position_ = RoundUp(start, kAlignment);
-    limit_ = keep->end();
-#ifdef DEBUG
-    // Zap the contents of the kept segment (but not the header).
-    memset(start, kZapDeadByte, keep->capacity());
-#endif
-  } else {
-    position_ = limit_ = 0;
-  }
-
-  // Update the head segment to be the kept segment (if any).
-  segment_head_ = keep;
-}
-
-
-void Zone::DeleteKeptSegment() {
-  if (segment_head_ != NULL) {
-    DeleteSegment(segment_head_, segment_head_->size());
-    segment_head_ = NULL;
-  }
-}
-
-
 Address Zone::NewExpand(int size) {
   // Make sure the requested size is already properly aligned and that
   // there isn't enough room in the Zone to satisfy the request.
   ASSERT(size == RoundDown(size, kAlignment));
   ASSERT(size > limit_ - position_);
 
   // Compute the new segment size. We use a 'high water mark'
   // strategy, where we increase the segment size every time we expand
   // except that we employ a maximum segment size when we delete. This
   // is to avoid excessive malloc() and free() overhead.
@@ skipping 30 matching lines @@
     V8::FatalProcessOutOfMemory("Zone");
     return NULL;
   }
   limit_ = segment->end();
   ASSERT(position_ <= limit_);
   return result;
 }
 
 
 } }  // namespace v8::internal