Use memcpy in List::AddAll for fundamental types.

src/list-inl.h

 // Copyright 2006-2009 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_LIST_INL_H_
 #define V8_LIST_INL_H_
 
 #include "src/list.h"
 
 #include "src/base/platform/platform.h"
@@ skipping 15 matching lines @@
 template<typename T, class P>
 void List<T, P>::AddAll(const List<T, P>& other, P alloc) {
   AddAll(other.ToVector(), alloc);
 }
 
 
 template<typename T, class P>
 void List<T, P>::AddAll(const Vector<T>& other, P alloc) {
   int result_length = length_ + other.length();
   if (capacity_ < result_length) Resize(result_length, alloc);
-  for (int i = 0; i < other.length(); i++) {
-    data_[length_ + i] = other.at(i);
+  if (std::is_fundamental<T>::value) {

[Sven Panne, 2014/10/24 08:04:00]

std:is_fundamental is a C++11 header feature, so we can't use that for now.

+    memcpy(data_ + length_, other.start(), sizeof(*data_) * other.length());
+  } else {
+    for (int i = 0; i < other.length(); i++) data_[length_ + i] = other.at(i);
   }
   length_ = result_length;
 }
 
 
 // Use two layers of inlining so that the non-inlined function can
 // use the same implementation as the inlined version.
 template<typename T, class P>
 void List<T, P>::ResizeAdd(const T& element, P alloc) {
   ResizeAddInternal(element, alloc);
@@ skipping 204 matching lines @@
 
 template <typename T>
 int SortedListBSearch(const List<T>& list, T elem) {
   return SortedListBSearch<T, ElementCmp<T> > (list, ElementCmp<T>(elem));
 }
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_LIST_INL_H_