Reapplying changes from r4318

src/heap-inl.h

 // Copyright 2006-2008 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 222 matching lines @@
   }
 }
 
 
 void Heap::CopyBlock(Object** dst, Object** src, int byte_size) {
   ASSERT(IsAligned(byte_size, kPointerSize));
   CopyWords(dst, src, byte_size / kPointerSize);
 }
 
 
+void Heap::MoveBlock(Object** dst, Object** src, size_t byte_size) {
+  ASSERT(IsAligned<size_t>(byte_size, kPointerSize));
+
+  int size_in_words = byte_size / kPointerSize;
+
+  if ((dst < src) || (dst >= (src + size_in_words))) {
+    ASSERT((dst >= (src + size_in_words)) ||
+           ((OffsetFrom(reinterpret_cast<Address>(src)) -
+             OffsetFrom(reinterpret_cast<Address>(dst))) >= kPointerSize));
+
+    Object** end = src + size_in_words;
+
+    while (src != end) {
+      *dst++ = *src++;
+    }
+  } else {
+    memmove(dst, src, byte_size);
+  }
+}
+
+
 void Heap::ScavengeObject(HeapObject** p, HeapObject* object) {
   ASSERT(InFromSpace(object));
 
   // We use the first word (where the map pointer usually is) of a heap
   // object to record the forwarding pointer.  A forwarding pointer can
   // point to an old space, the code space, or the to space of the new
   // generation.
   MapWord first_word = object->map_word();
 
   // If the first word is a forwarding address, the object has already been
@@ skipping 168 matching lines @@
 
 
 void ExternalStringTable::ShrinkNewStrings(int position) {
   new_space_strings_.Rewind(position);
   Verify();
 }
 
 } }  // namespace v8::internal
 
 #endif  // V8_HEAP_INL_H_