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

src/regexp-stack.cc

Index: src/regexp-stack.cc
diff --git a/src/regexp-stack.cc b/src/regexp-stack.cc
index 325a1496c98c9a26d05c9fffc1c97be132e401f0..fc4114af5de202d49507b9be3a1902c43b3d1881 100644
--- a/src/regexp-stack.cc
+++ b/src/regexp-stack.cc
@@ -57,9 +57,7 @@ RegExpStack::~RegExpStack() {
 
 char* RegExpStack::ArchiveStack(char* to) {
   size_t size = sizeof(thread_local_);
-  memcpy(reinterpret_cast<void*>(to),
-         &thread_local_,
-         size);
+  OS::MemCopy(reinterpret_cast<void*>(to), &thread_local_, size);
   thread_local_ = ThreadLocal();
   return to + size;
 }
@@ -67,7 +65,7 @@ char* RegExpStack::ArchiveStack(char* to) {
 
 char* RegExpStack::RestoreStack(char* from) {
   size_t size = sizeof(thread_local_);
-  memcpy(&thread_local_, reinterpret_cast<void*>(from), size);
+  OS::MemCopy(&thread_local_, reinterpret_cast<void*>(from), size);
   return from + size;
 }
 
@@ -95,10 +93,11 @@ Address RegExpStack::EnsureCapacity(size_t size) {
     Address new_memory = NewArray<byte>(static_cast<int>(size));
     if (thread_local_.memory_size_ > 0) {
       // Copy original memory into top of new memory.
-      memcpy(reinterpret_cast<void*>(
-          new_memory + size - thread_local_.memory_size_),
-             reinterpret_cast<void*>(thread_local_.memory_),
-             thread_local_.memory_size_);
+      OS::MemCopy(
+          reinterpret_cast<void*>(
+              new_memory + size - thread_local_.memory_size_),
+          reinterpret_cast<void*>(thread_local_.memory_),
+          thread_local_.memory_size_);
       DeleteArray(thread_local_.memory_);
     }
     thread_local_.memory_ = new_memory;