Implement leaf runtime call stub on ARM and corresponding call redirection

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.
@@ skipping 61 matching lines @@
 
   // Implementation of atomic compare and exchange in the same synchronization
   // domain as other synchronization primitive instructions (e.g. ldrex, strex).
   static uword CompareExchange(uword* address,
                                uword compare_value,
                                uword new_value);
 
   // Runtime and native call support.
   enum CallKind {
     kRuntimeCall,
+    kLeafRuntimeCall,
     kNativeCall
   };
   static uword RedirectExternalReference(uword function, CallKind call_kind);
 
   void Longjmp(int32_t pc, int32_t sp, int32_t fp, const Instance& object);
 
  private:
   // Known bad pc value to ensure that the simulator does not execute
   // without being properly setup.
   static const uword kBadLR = -1;
@@ skipping 132 matching lines @@
   }
 
   friend class SimulatorDebugger;
   friend class SimulatorSetjmpBuffer;
   DISALLOW_COPY_AND_ASSIGN(Simulator);
 };
 
 }  // namespace dart
 
 #endif  // VM_SIMULATOR_ARM_H_