Support FrameLookup vm test on ARM, requiring among other things:

runtime/vm/simulator_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.
 
 // Declares a Simulator for ARM instructions if we are not generating a native
 // ARM binary. This Simulator allows us to run and debug ARM code generation on
 // regular desktop machines.
 // Dart calls into generated code by "calling" the InvokeDartCode stub,
 // which will start execution in the Simulator or forwards to the real entry
 // on a ARM HW platform.
 
 #ifndef VM_SIMULATOR_ARM_H_
 #define VM_SIMULATOR_ARM_H_
 
 #ifndef VM_SIMULATOR_H_
 #error Do not include simulator_arm.h directly; use simulator.h.
 #endif
 
-#include "vm/allocation.h"
 #include "vm/constants_arm.h"
 #include "vm/object.h"
 
 namespace dart {
 
 class Isolate;
 class SimulatorSetjmpBuffer;
 
 class Simulator {
  public:
@@ skipping 18 matching lines @@
 
   // Accessors for VFP register state.
   void set_sregister(SRegister reg, float value);
   float get_sregister(SRegister reg) const;
   void set_dregister(DRegister reg, double value);
   double get_dregister(DRegister reg) const;
 
   // Accessor to the internal simulator stack top.
   uword StackTop() const;
 
-  // Executes ARM instructions until the PC reaches end_sim_pc.
-  void Execute();
+  // The isolate's top_exit_frame_info refers to a Dart frame in the simulator
+  // stack. The simulator's top_exit_frame_info refers to a C++ frame in the
+  // native stack.
+  uword top_exit_frame_info() const { return top_exit_frame_info_; }
+  void set_top_exit_frame_info(uword value) { top_exit_frame_info_ = value; }
 
   // Call on program start.
   static void InitOnce();
 
   // Dart generally calls into generated code with 5 parameters. This is a
   // convenience function, which sets up the simulator state and grabs the
   // result on return.
   int64_t Call(int32_t entry,
                int32_t parameter0,
                int32_t parameter1,
@@ skipping 42 matching lines @@
   bool fp_z_flag_;
   bool fp_c_flag_;
   bool fp_v_flag_;
 
   // Simulator support.
   char* stack_;
   bool pc_modified_;
   int icount_;
   static int32_t flag_stop_sim_at_;
   SimulatorSetjmpBuffer* last_setjmp_buffer_;
+  uword top_exit_frame_info_;
 
   // Registered breakpoints.
   Instr* break_pc_;
   int32_t break_instr_;
 
   // Illegal memory access support.
   static bool IsIllegalAddress(uword addr) {
     return addr < 64*1024;
   }
   void HandleIllegalAccess(uword addr, Instr* instr);
@@ skipping 80 matching lines @@
   void DecodeType2(Instr* instr);
   void DecodeType3(Instr* instr);
   void DecodeType4(Instr* instr);
   void DecodeType5(Instr* instr);
   void DecodeType6(Instr* instr);
   void DecodeType7(Instr* instr);
 
   // Executes one instruction.
   void InstructionDecode(Instr* instr);
 
+  // Executes ARM instructions until the PC reaches kEndSimulatingPC.
+  void Execute();
+
   // Longjmp support for exceptions.
   SimulatorSetjmpBuffer* last_setjmp_buffer() {
     return last_setjmp_buffer_;
   }
   void set_last_setjmp_buffer(SimulatorSetjmpBuffer* buffer) {
     last_setjmp_buffer_ = buffer;
   }
 
   friend class SimulatorDebugger;
   friend class SimulatorSetjmpBuffer;
   DISALLOW_COPY_AND_ASSIGN(Simulator);
 };
 
 }  // namespace dart
 
 #endif  // VM_SIMULATOR_ARM_H_