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diff --git a/tensorflow/compiler/xla/window_util.h b/tensorflow/compiler/xla/window_util.h
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+/* 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.
+==============================================================================*/
+
+#ifndef TENSORFLOW_COMPILER_XLA_WINDOW_UTIL_H_
+#define TENSORFLOW_COMPILER_XLA_WINDOW_UTIL_H_
+
+#include "tensorflow/compiler/xla/types.h"
+#include "tensorflow/compiler/xla/xla_data.pb.h"
+
+namespace xla {
+namespace window_util {
+
+string ToString(const WindowDimension& dim);
+string ToString(const Window& window);
+
+// The below functions return true if the given field is set to have a
+// non-trivial effect, e.g. having a stride means that the stride of some
+// dimension is not one. Whether the proto field is populated is not a
+// consideration.
+
+bool HasStride(const Window& window);
+bool HasPadding(const Window& window);
+bool HasEvenPadding(const Window& window);
+bool HasNegativePadding(const Window& window);
+
+bool HasBaseDilation(const Window& window);
+bool HasWindowDilation(const Window& window);
+bool HasDilation(const Window& window);
+
+// Returns the new bound after dilation.
+//
+// If a window with the given bound in some dimension is dilated with the given
+// dilation factor in that dimension, then the value returned is the bound for
+// the array in that dimension after dilation.
+//
+// For a 1D array with 3 entries 1, 2, 3, a dilation factor of 2 yields a new
+// window with values 1, x, 2, x, 3, where x indicates holes left by the
+// dilation. So DilatedBound(3, 2) == 5.
+int64 DilatedBound(int64 bound, int64 dilation);
+
+// Returns the number of valid positions of a window with the given size and
+// stride within an array with the given bound. This is the bound of an output
+// array with one element per valid position of the window.
+//
+// For example, for arguments of (bound=5, window_size=2, stride=2), the
+// returned value is 2. There are valid positions at offset 0 and offset 2,
+// while offset 4 is not valid since the window's last entry would be at 5,
+// which is beyond the bound of 5.
+int64 StridedBound(int64 bound, int64 window_size, int64 stride);
+
+}  // namespace window_util
+}  // namespace xla
+
+#endif  // TENSORFLOW_COMPILER_XLA_WINDOW_UTIL_H_