message: Compile TensorFlow with /arch:AVX on Windows
  /arch:AVX is the correpsonding option in MSVC for gcc's --march=native
diff: @@ -484,6 +484,8 @@ def set_cc_opt_flags(environ_cp):
  if is_ppc64le():
  # gcc on ppc64le does not support -march, use mcpu instead
  default_cc_opt_flags = '-mcpu=native'
  + elif is_windows():
  + default_cc_opt_flags = '/arch:AVX'
  else:
  default_cc_opt_flags = '-march=native'
  question = ('Please specify optimization flags to use during compilation when'
  @@ -494,7 +496,7 @@ def set_cc_opt_flags(environ_cp):
  for opt in cc_opt_flags.split():
  write_to_bazelrc('build:opt --copt=%s' % opt)
  # It should be safe on the same build host.
  - if not is_ppc64le():
  + if not is_ppc64le() and not is_windows():
  write_to_bazelrc('build:opt --host_copt=-march=native')
  write_to_bazelrc('build:opt --define with_default_optimizations=true')
  # TODO(mikecase): Remove these default defines once we are able to get
  