Revert "Remove V8_HOST_CAN_READ_UNALIGNED and its uses."

src/regexp-macro-assembler-irregexp.h

 // 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.
 
 #ifndef V8_REGEXP_MACRO_ASSEMBLER_IRREGEXP_H_
 #define V8_REGEXP_MACRO_ASSEMBLER_IRREGEXP_H_
 
 #include "src/regexp-macro-assembler.h"
 
 namespace v8 {
@@ skipping 13 matching lines @@
   // owned by the assembler and deallocated upon destruction of the assembler.
   //
   // If the provided buffer is not NULL, the assembler uses the provided buffer
   // for code generation and assumes its size to be buffer_size. If the buffer
   // is too small, a fatal error occurs. No deallocation of the buffer is done
   // upon destruction of the assembler.
   RegExpMacroAssemblerIrregexp(Vector<byte>, Zone* zone);
   virtual ~RegExpMacroAssemblerIrregexp();
   // The byte-code interpreter checks on each push anyway.
   virtual int stack_limit_slack() { return 1; }
-  virtual bool CanReadUnaligned() { return false; }
   virtual void Bind(Label* label);
   virtual void AdvanceCurrentPosition(int by);  // Signed cp change.
   virtual void PopCurrentPosition();
   virtual void PushCurrentPosition();
   virtual void Backtrack();
   virtual void GoTo(Label* label);
   virtual void PushBacktrack(Label* label);
   virtual bool Succeed();
   virtual void Fail();
   virtual void PopRegister(int register_index);
@@ skipping 74 matching lines @@
   static const int kInvalidPC = -1;
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(RegExpMacroAssemblerIrregexp);
 };
 
 #endif  // V8_INTERPRETED_REGEXP
 
 } }  // namespace v8::internal
 
 #endif  // V8_REGEXP_MACRO_ASSEMBLER_IRREGEXP_H_