Remove CheckNotRegistersEqual regexp-masm function from all architectures.

src/x64/regexp-macro-assembler-x64.cc

 // Copyright 2011 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 505 matching lines @@
 
   // Success.
   // Set current character position to position after match.
   __ movq(rdi, rbx);
   __ subq(rdi, rsi);
 
   __ bind(&fallthrough);
 }
 
 
-void RegExpMacroAssemblerX64::CheckNotRegistersEqual(int reg1,
-                                                     int reg2,
-                                                     Label* on_not_equal) {
-  __ movq(rax, register_location(reg1));
-  __ cmpq(rax, register_location(reg2));
-  BranchOrBacktrack(not_equal, on_not_equal);
-}
-
-
 void RegExpMacroAssemblerX64::CheckNotCharacter(uint32_t c,
                                                 Label* on_not_equal) {
   __ cmpl(current_character(), Immediate(c));
   BranchOrBacktrack(not_equal, on_not_equal);
 }
 
 
 void RegExpMacroAssemblerX64::CheckCharacterAfterAnd(uint32_t c,
                                                      uint32_t mask,
                                                      Label* on_equal) {
@@ skipping 915 matching lines @@
   }
 }
 
 #undef __
 
 #endif  // V8_INTERPRETED_REGEXP
 
 }}  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_X64