Replace OS::MemCopy with OS::MemMove (just as fast but more flexible).

src/isolate.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 1544 matching lines @@
   }
 #endif  // ENABLE_DEBUGGER_SUPPORT
   if (it.done()) return Handle<Context>::null();
   JavaScriptFrame* frame = it.frame();
   Context* context = Context::cast(frame->context());
   return Handle<Context>(context->native_context());
 }
 
 
 char* Isolate::ArchiveThread(char* to) {
-  memcpy(to, reinterpret_cast<char*>(thread_local_top()),
-         sizeof(ThreadLocalTop));
+  OS::MemCopy(to, reinterpret_cast<char*>(thread_local_top()),
+              sizeof(ThreadLocalTop));
   InitializeThreadLocal();
   clear_pending_exception();
   clear_pending_message();
   clear_scheduled_exception();
   return to + sizeof(ThreadLocalTop);
 }
 
 
 char* Isolate::RestoreThread(char* from) {
-  memcpy(reinterpret_cast<char*>(thread_local_top()), from,
-         sizeof(ThreadLocalTop));
+  OS::MemCopy(reinterpret_cast<char*>(thread_local_top()), from,
+              sizeof(ThreadLocalTop));
   // This might be just paranoia, but it seems to be needed in case a
   // thread_local_top_ is restored on a separate OS thread.
 #ifdef USE_SIMULATOR
 #ifdef V8_TARGET_ARCH_ARM
   thread_local_top()->simulator_ = Simulator::current(this);
 #elif V8_TARGET_ARCH_MIPS
   thread_local_top()->simulator_ = Simulator::current(this);
 #endif
 #endif
   ASSERT(context() == NULL || context()->IsContext());
@@ skipping 819 matching lines @@
 
 #ifdef DEBUG
 #define ISOLATE_FIELD_OFFSET(type, name, ignored)                       \
 const intptr_t Isolate::name##_debug_offset_ = OFFSET_OF(Isolate, name##_);
 ISOLATE_INIT_LIST(ISOLATE_FIELD_OFFSET)
 ISOLATE_INIT_ARRAY_LIST(ISOLATE_FIELD_OFFSET)
 #undef ISOLATE_FIELD_OFFSET
 #endif
 
 } }  // namespace v8::internal