Begins work on ARM64, first assembler test.

runtime/vm/assembler.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_ASSEMBLER_H_
 #define VM_ASSEMBLER_H_
 
 #include "platform/assert.h"
 #include "vm/allocation.h"
 #include "vm/globals.h"
 #include "vm/growable_array.h"
 #include "vm/object.h"
 
 namespace dart {
 
-#if defined(TARGET_ARCH_ARM) || defined(TARGET_ARCH_MIPS)
+#if defined(TARGET_ARCH_ARM) ||                                                \
+    defined(TARGET_ARCH_ARM64) ||                                              \
+    defined(TARGET_ARCH_MIPS)
 DECLARE_FLAG(bool, use_far_branches);
 #endif
 
 // Forward declarations.
 class Assembler;
 class AssemblerFixup;
 class AssemblerBuffer;
 class MemoryRegion;
 
 
@@ skipping 183 matching lines @@
 
 }  // namespace dart
 
 
 #if defined(TARGET_ARCH_IA32)
 #include "vm/assembler_ia32.h"
 #elif defined(TARGET_ARCH_X64)
 #include "vm/assembler_x64.h"
 #elif defined(TARGET_ARCH_ARM)
 #include "vm/assembler_arm.h"
+#elif defined(TARGET_ARCH_ARM64)
+#include "vm/assembler_arm64.h"
 #elif defined(TARGET_ARCH_MIPS)
 #include "vm/assembler_mips.h"
 #else
 #error Unknown architecture.
 #endif
 
 #endif  // VM_ASSEMBLER_H_