Move regexp implementation into its own folder.

src/regexp/mips64/regexp-macro-assembler-mips64.cc

 // Copyright 2012 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.
 
 #include "src/v8.h"
 
 #if V8_TARGET_ARCH_MIPS64
 
+#include "src/regexp/mips64/regexp-macro-assembler-mips64.h"
+
 #include "src/code-stubs.h"
 #include "src/log.h"
 #include "src/macro-assembler.h"
-#include "src/regexp-macro-assembler.h"
-#include "src/regexp-stack.h"
+#include "src/regexp/regexp-macro-assembler.h"
+#include "src/regexp/regexp-stack.h"
 #include "src/unicode.h"
 
-#include "src/mips64/regexp-macro-assembler-mips64.h"
-
 namespace v8 {
 namespace internal {
 
 #ifndef V8_INTERPRETED_REGEXP
 /*
  * This assembler uses the following register assignment convention
  * - t3 : Temporarily stores the index of capture start after a matching pass
  *        for a global regexp.
  * - a5 : Pointer to current code object (Code*) including heap object tag.
  * - a6 : Current position in input, as negative offset from end of string.
@@ skipping 1255 matching lines @@
 }
 
 #undef __
 
 #endif  // V8_INTERPRETED_REGEXP
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_MIPS64