Background compilation work:

runtime/vm/assembler_mips.cc

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/globals.h"  // NOLINT
 #if defined(TARGET_ARCH_MIPS)
 
 #include "vm/assembler.h"
 #include "vm/longjump.h"
 #include "vm/runtime_entry.h"
@@ skipping 443 matching lines @@
     subu(rd, rs, rt);
     xor_(ro, rd, rs);
     xor_(TMP, rs, rt);
     and_(ro, TMP, ro);
   }
 }
 
 
 void Assembler::CheckCodePointer() {
 #ifdef DEBUG
+  Comment("CheckCodePointer");
   Label cid_ok, instructions_ok;
   Push(CMPRES1);
   Push(CMPRES2);
   LoadClassId(CMPRES1, CODE_REG);
   BranchEqual(CMPRES1, Immediate(kCodeCid), &cid_ok);
   break_(0);
   Bind(&cid_ok);
   GetNextPC(CMPRES1, TMP);
   const intptr_t entry_offset = CodeSize() - Instr::kInstrSize +
       Instructions::HeaderSize() - kHeapObjectTag;
@@ skipping 857 matching lines @@
   Label stop;
   b(&stop);
   Emit(reinterpret_cast<int32_t>(message));
   Bind(&stop);
   break_(Instr::kStopMessageCode);
 }
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_MIPS