Removes branches from LoadTaggedClassIdMayBeSmi.

runtime/vm/assembler_mips.h

 // 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.
 
 #ifndef VM_ASSEMBLER_MIPS_H_
 #define VM_ASSEMBLER_MIPS_H_
 
 #ifndef VM_ASSEMBLER_H_
 #error Do not include assembler_mips.h directly; use assembler.h instead.
 #endif
@@ skipping 585 matching lines @@
 
   void movn(Register rd, Register rs, Register rt) {
     EmitRType(SPECIAL, rs, rt, rd, 0, MOVN);
   }
 
   // Move if floating point true.
   void movt(Register rd, Register rs) {
     EmitRType(SPECIAL, rs, R1, rd, 0, MOVCI);
   }
 
+  // rd <- (rt == 0) ? rs : rd;
   void movz(Register rd, Register rs, Register rt) {
     EmitRType(SPECIAL, rs, rt, rd, 0, MOVZ);
   }
 
   void movs(FRegister fd, FRegister fs) {
     EmitFpuRType(COP1, FMT_S, F0, fs, fd, COP1_MOV);
   }
 
   void mtc1(Register rt, FRegister fs) {
     Emit(COP1 << kOpcodeShift |
@@ skipping 738 matching lines @@
                                   Register value,
                                   Label* no_update);
 
   DISALLOW_ALLOCATION();
   DISALLOW_COPY_AND_ASSIGN(Assembler);
 };
 
 }  // namespace dart
 
 #endif  // VM_ASSEMBLER_MIPS_H_