def create_eval_loop_fn(self, has_state: bool):
"""Creates an eval loop from the current step function and options.
Args:
has_state: If the step function has state, state will be kept in the loop.
Returns:
The eval loop function, i.e. wrapper of multiple eval steps.
"""
eval_step_fn = self.eval_step
if self._eval_options.use_tf_while_loop:
# TODO(b/176126742): tf.while_loop doesn't support `None` as a loop input
# even when it is not used inside the loop. To workaround this limitation,
# we have to build two tf.functions for it.
if has_state:
loop_fn = loop_fns.create_tf_while_loop_fn_with_state(
eval_step_fn)
else:
loop_fn = loop_fns.create_tf_while_loop_fn(eval_step_fn)
loop_fn = tf.function(loop_fn)
else:
if self._eval_options.use_tf_function:
eval_step_fn = tf.function(eval_step_fn)
loop_fn = loop_fns.create_loop_fn(eval_step_fn)
return loop_fn
def _create_eval_loop_fn(eval_step_fn, has_state: bool,
options: StandardEvaluatorOptions):
"""Create evaluation loop function."""
if options.use_tf_while_loop:
# TODO(b/176126742): tf.while_loop doesn't support `None` as a loop input
# even when it is not used inside the loop. To workaround this limitation,
# we have to build two tf.functions for it.
if has_state:
loop_fn = loop_fns.create_tf_while_loop_fn_with_state(eval_step_fn)
else:
loop_fn = loop_fns.create_tf_while_loop_fn(eval_step_fn)
loop_fn = tf.function(loop_fn)
else:
if options.use_tf_function:
eval_step_fn = tf.function(eval_step_fn)
loop_fn = loop_fns.create_loop_fn(eval_step_fn)
return loop_fn
