Adds mrc instruction to arm simulator, assembler, disassembler.

runtime/vm/assembler_macros_arm.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.
 // The class 'AssemblerMacros' contains assembler instruction groups that
 // are used in Dart.
 
 #ifndef VM_ASSEMBLER_MACROS_ARM_H_
 #define VM_ASSEMBLER_MACROS_ARM_H_
 
 #ifndef VM_ASSEMBLER_MACROS_H_
@@ skipping 26 matching lines @@
   // enable easy access to the RawInstruction object of code corresponding
   // to this frame.
   static void EnterDartFrame(Assembler* assembler, intptr_t frame_size);
   static void LeaveDartFrame(Assembler* assembler);
 
   // Set up a stub frame so that the stack traversal code can easily identify
   // a stub frame.
   static void EnterStubFrame(Assembler* assembler);
   static void LeaveStubFrame(Assembler* assembler);
 
+  // Check whether we have an integer division instruction.
+  // After, rd will be non-zero if we have sdiv and udiv instructions.
+  static void HasDiv(Assembler* assembler, Register rd);

[regis, 2013/03/04 21:54:52]

This method is not necessary. The code testing for this feature should be
executed once in CPUFeatures::InitOnce().

+
   // Instruction pattern from entrypoint is used in dart frame prologs
   // to set up the frame and save a PC which can be used to figure out the
   // RawInstruction object corresponding to the code running in the frame.
   static const intptr_t kOffsetOfSavedPCfromEntrypoint = Instr::kPCReadOffset;
 };
 
 }  // namespace dart.
 
 #endif  // VM_ASSEMBLER_MACROS_ARM_H_