Use the BitField class for Code::Flags.

src/mips/macro-assembler-mips.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 423 matching lines @@
       Branch(miss, ne, key, Operand(at));
     }
   }
 
   bind(&done);
   // Check that the value is a normal property.
   // reg2: elements + (index * kPointerSize).
   const int kDetailsOffset =
       NumberDictionary::kElementsStartOffset + 2 * kPointerSize;
   lw(reg1, FieldMemOperand(reg2, kDetailsOffset));
-  And(at, reg1, Operand(Smi::FromInt(PropertyDetails::TypeField::mask())));
+  And(at, reg1, Operand(Smi::FromInt(PropertyDetails::TypeField::kMask)));
   Branch(miss, ne, at, Operand(zero_reg));
 
   // Get the value at the masked, scaled index and return.
   const int kValueOffset =
       NumberDictionary::kElementsStartOffset + kPointerSize;
   lw(result, FieldMemOperand(reg2, kValueOffset));
 }
 
 
 // ---------------------------------------------------------------------------
@@ skipping 3948 matching lines @@
        opcode == BGTZL);
   opcode = (cond == eq) ? BEQ : BNE;
   instr = (instr & ~kOpcodeMask) | opcode;
   masm_.emit(instr);
 }
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_MIPS