STT-tensorflow/tensorflow/python/grappler/constant_folding_test.py
Saurabh Saxena 5e9107066d Add read variable op to function control outputs
After inlining, we convert control dependencies to the function call to depend
on all control outputs. Although read variable ops doesn't have side effect
itself, it must be executed before variable updates after the function call.

Note that it's not enough to convert control dependencies to the function call
to depend on both control outputs and data outputs of the function call. The
read variable ops can be inputs to ops that have side effects, e.g. assert and
print, which are not the function data outputs.

PiperOrigin-RevId: 338391537
Change-Id: Ibc843c1a584088e54010685ebce678b047f7d94d
2020-10-21 20:28:26 -07:00

112 lines
3.6 KiB
Python

# Copyright 2017 The TensorFlow Authors. All Rights Reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
# ==============================================================================
"""Tests for Grappler Constant Folding."""
from __future__ import absolute_import
from __future__ import division
from __future__ import print_function
import numpy as np
from tensorflow.python.eager import backprop
from tensorflow.python.eager import context
from tensorflow.python.eager import def_function
from tensorflow.python.framework import dtypes
from tensorflow.python.framework import ops
from tensorflow.python.framework import test_util
from tensorflow.python.ops import array_ops
from tensorflow.python.ops import control_flow_ops
from tensorflow.python.ops import functional_ops
from tensorflow.python.ops import math_ops
from tensorflow.python.ops import resource_variable_ops
from tensorflow.python.platform import test
class ConstantFoldingTest(test.TestCase):
# See b/76008022.
def testScanInsideWhile(self):
def loop_cond(idx_step, *unused_args):
return idx_step < 1
def loop_body(idx_step, y):
x = array_ops.zeros([10, 20, 30], dtype=dtypes.float32)
x = functional_ops.scan(
math_ops.add,
x,
initializer=array_ops.zeros([20, 30], dtype=dtypes.float32),
back_prop=False,
parallel_iterations=1)
with ops.device('/cpu:0'):
y = array_ops.identity(x)
return idx_step + 1, y
if test.is_gpu_available(cuda_only=True):
init_y = array_ops.zeros([10, 20, 30], dtype=dtypes.float32)
_, y = control_flow_ops.while_loop(
loop_cond,
loop_body,
loop_vars=[0, init_y],
back_prop=False,
parallel_iterations=1)
y_v = self.evaluate(y)
self.assertAllEqual(np.zeros([10, 20, 30]), y_v)
# See b/159753857.
def testGradientGraphOptimization(self):
@def_function.function
def f(x, y):
with backprop.GradientTape() as tape:
z = math_ops.mul(x, array_ops.zeros_like(x))
l = math_ops.add(z, y)
l = math_ops.reduce_sum(l)
gx, gy = tape.gradient(l, [x, y])
x.assign_add(gx)
y.assign_add(gy)
return x + y
# XLA completely optimizes away the variable reads and
# assignments, so skip the test.
if test_util.is_xla_enabled():
self.skipTest('Not relevant for XLA')
with context.eager_mode():
x = resource_variable_ops.ResourceVariable(
np.random.uniform(size=[2, 2]), dtype=dtypes.float32)
y = resource_variable_ops.ResourceVariable(
np.random.uniform(size=[2, 2]), dtype=dtypes.float32)
with context.collect_graphs(optimized=True) as graphs:
f(x, y).numpy()
self.assertLen(graphs, 1)
assign_count = 0
for node in graphs[0].node:
if node.op == 'AssignAddVariableOp':
self.assertEqual(node.input[0], 'y')
assign_count += 1
# Make sure that the only variable update that remains after
# grappler optimization is that of y.
self.assertEqual(assign_count, 1)
self.assertLen(graphs[0].node, 11)
if __name__ == '__main__':
test.main()