Add thread-safety to creation of MemCopy and modulo functions.

src/v8utils.h

 // Copyright 2010 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 236 matching lines @@
  private:
   Vector<char> buffer_;
   int position_;
 
   bool is_finalized() const { return position_ < 0; }
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(StringBuilder);
 };
 
 
-// Custom memcpy implementation for platforms where the standard version
-// may not be good enough.
-#if defined(V8_TARGET_ARCH_IA32)
-
-// The default memcpy on ia32 architectures is generally not as efficient
-// as possible. (If any further ia32 platforms are introduced where the
-// memcpy function is efficient, exclude them from this branch).
-
-typedef void (*MemCopyFunction)(void* dest, const void* src, size_t size);
-
-// Implemented in codegen-<arch>.cc.
-MemCopyFunction CreateMemCopyFunction();
-
-// Copy memory area to disjoint memory area.
-static inline void MemCopy(void* dest, const void* src, size_t size) {
-  static MemCopyFunction memcopy = CreateMemCopyFunction();
-  (*memcopy)(dest, src, size);
-#ifdef DEBUG
-  CHECK_EQ(0, memcmp(dest, src, size));
-#endif
-}
-
-// Limit below which the extra overhead of the MemCopy function is likely
-// to outweigh the benefits of faster copying.
-static const int kMinComplexMemCopy = 64;
-
-#else  // V8_TARGET_ARCH_IA32
-
-static inline void MemCopy(void* dest, const void* src, size_t size) {
-  memcpy(dest, src, size);
-}
-
-static const int kMinComplexMemCopy = 256;
-
-#endif  // V8_TARGET_ARCH_IA32
-
-
 // Copy from ASCII/16bit chars to ASCII/16bit chars.
 template <typename sourcechar, typename sinkchar>
 static inline void CopyChars(sinkchar* dest, const sourcechar* src, int chars) {
   sinkchar* limit = dest + chars;
 #ifdef V8_HOST_CAN_READ_UNALIGNED
   if (sizeof(*dest) == sizeof(*src)) {
-    if (chars >= static_cast<int>(kMinComplexMemCopy / sizeof(*dest))) {
-      MemCopy(dest, src, chars * sizeof(*dest));
+    if (chars >= static_cast<int>(OS::kMinComplexMemCopy / sizeof(*dest))) {
+      OS::MemCopy(dest, src, chars * sizeof(*dest));
       return;
     }
     // Number of characters in a uintptr_t.
     static const int kStepSize = sizeof(uintptr_t) / sizeof(*dest);  // NOLINT
     while (dest <= limit - kStepSize) {
       *reinterpret_cast<uintptr_t*>(dest) =
           *reinterpret_cast<const uintptr_t*>(src);
       dest += kStepSize;
       src += kStepSize;
     }
@@ skipping 33 matching lines @@
 
   const char* data_;
   size_t length_;
   bool remove_file_on_cleanup_;
 };
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_V8UTILS_H_