DBC: Adds simdbc64 target, adds arm64 arithmetic overflow logic

tools/utils.py

 # 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.
 
 # This file contains a set of utilities functions used by other Python-based
 # scripts.
 
 import commands
 import datetime
 import json
@@ skipping 223 matching lines @@
   'armv6': 'arm',
   'armv5te': 'arm',
   'arm64': 'arm',
   'mips': 'mips',
   'simarm': 'ia32',
   'simarmv6': 'ia32',
   'simarmv5te': 'ia32',
   'simmips': 'ia32',
   'simarm64': 'ia32',
   'simdbc': 'ia32',
+  'simdbc64': 'ia32',
 }
 
 ARCH_GUESS = GuessArchitecture()
 BASE_DIR = os.path.abspath(os.path.join(os.curdir, '..'))
 DART_DIR = os.path.abspath(os.path.join(__file__, '..', '..'))
 VERSION_FILE = os.path.join(DART_DIR, 'tools', 'VERSION')
 
 def GetBuildbotGSUtilPath():
   gsutil = '/b/build/scripts/slave/gsutil'
   if platform.system() == 'Windows':
@@ skipping 397 matching lines @@
     os.chdir(self._working_directory)
 
   def __exit__(self, *_):
     print "Enter directory = ", self._old_cwd
     os.chdir(self._old_cwd)
 
 
 if __name__ == "__main__":
   import sys
   Main()