Cosmetic (ARM/MIPS): Use FieldMemOperand where appropriate.

src/mips/full-codegen-mips.cc

 // Copyright 2012 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 2959 matching lines @@
 
     CpuFeatures::Scope scope(FPU);
     // 0x41300000 is the top half of 1.0 x 2^20 as a double.
     __ li(a1, Operand(0x41300000));
     // Move 0x41300000xxxxxxxx (x = random bits in v0) to FPU.
     __ Move(f12, v0, a1);
     // Move 0x4130000000000000 to FPU.
     __ Move(f14, zero_reg, a1);
     // Subtract and store the result in the heap number.
     __ sub_d(f0, f12, f14);
-    __ sdc1(f0, MemOperand(s0, HeapNumber::kValueOffset - kHeapObjectTag));
+    __ sdc1(f0, FieldMemOperand(s0, HeapNumber::kValueOffset));
     __ mov(v0, s0);
   } else {
     __ PrepareCallCFunction(2, a0);
     __ mov(a0, s0);
     __ lw(a1, ContextOperand(cp, Context::GLOBAL_INDEX));
     __ lw(a1, FieldMemOperand(a1, GlobalObject::kGlobalContextOffset));
     __ CallCFunction(
         ExternalReference::fill_heap_number_with_random_function(isolate()), 2);
   }
 
@@ skipping 1568 matching lines @@
   *context_length = 0;
   return previous_;
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_MIPS