Use a uniform way to emit code for all instructions.

runtime/vm/flow_graph_compiler.h

 // Copyright (c) 2012, 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_FLOW_GRAPH_COMPILER_H_
 #define VM_FLOW_GRAPH_COMPILER_H_
 
 #include "vm/allocation.h"
 #include "vm/assembler.h"
 #include "vm/code_descriptors.h"
@@ skipping 315 matching lines @@
                                const AbstractType& type,
                                Label* is_instance_lbl,
                                Label* is_not_instance_lbl);
   void GenerateStringTypeCheck(Register kClassIdReg,
                                Label* is_instance_lbl,
                                Label* is_not_instance_lbl);
   void GenerateListTypeCheck(Register kClassIdReg,
                              Label* is_instance_lbl);
 
   void EmitComment(Instruction* instr);
+  void EmitInstruction(Instruction* instr);
 
   void EmitOptimizedInstanceCall(ExternalLabel* target_label,
                                  const ICData& ic_data,
                                  const Array& arguments_descriptor,
                                  intptr_t argument_count,
                                  intptr_t deopt_id,
                                  intptr_t token_pos,
                                  LocationSummary* locs);
 
   void EmitInstanceCall(ExternalLabel* target_label,
@@ skipping 246 matching lines @@
   // that should be used when deoptimizing we store it in this variable.
   // In future AddDeoptStub should be moved out of the instruction template.
   Environment* pending_deoptimization_env_;
 
   DISALLOW_COPY_AND_ASSIGN(FlowGraphCompiler);
 };
 
 }  // namespace dart
 
 #endif  // VM_FLOW_GRAPH_COMPILER_H_