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diff --git a/tensorflow/compiler/jit/encapsulate_xla_computations_pass.h b/tensorflow/compiler/jit/encapsulate_xla_computations_pass.h
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+/* Copyright 2018 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.
+ ==============================================================================*/
+// Rewrites computations generated by the xla.compile() Python code into
+// XlaLaunch nodes.
+//
+// xla.compile() does two main things:
+// a) marks operators that make up an XLA computation with the attribute
+//    _xla_compile_id=XYZ, where XYZ is a unique key.
+// b) adds XlaClusterOutput nodes to represent outputs of the computation.
+//    These nodes are not marked with the _xla_compile_id attribute.
+
+#ifndef TENSORFLOW_COMPILER_JIT_ENCAPSULATE_XLA_COMPUTATIONS_PASS_H_
+#define TENSORFLOW_COMPILER_JIT_ENCAPSULATE_XLA_COMPUTATIONS_PASS_H_
+
+#include "tensorflow/core/common_runtime/optimization_registry.h"
+#include "tensorflow/core/graph/graph.h"
+#include "tensorflow/core/platform/env.h"
+
+    namespace tensorflow {
+
+// Encapsulates nodes marked with the _xla_compile_id attribute into
+// XlaLaunch operators.
+class EncapsulateXlaComputationsPass : public GraphOptimizationPass {
+ public:
+  static const char* const kXlaClusterAttr;  // _xla_compile_id
+
+  Status Run(const GraphOptimizationPassOptions& options) override;
+
+  // The following methods are public only for unit tests.
+
+  // This pass has two stages:
+  // a) first, we call EncapsulateSubgraphsPass to encapsulate all nodes
+  //    marked with the same _xla_compile_id attribute into functions. These
+  //    functions contain the computations to be passed to XlaLaunch. During
+  //    encapsulation, we sort the arguments into the order expected by
+  //    XlaLaunch.
+  static Status Encapsulate(std::unique_ptr<Graph>* graph,
+                            FunctionLibraryDefinition* flib_def);
+
+  // b) we rewrite the function calls generated in phase (a) into XlaLaunch
+  //    operators. We also convert the XlaClusterOutput output nodes of the
+  //    function call into the outputs of the XlaLaunch operator.
+  static Status BuildXlaLaunchOps(Graph* graph);
+};
+
+}  // namespace tensorflow
+
+#endif  // TENSORFLOW_COMPILER_JIT_ENCAPSULATE_XLA_COMPUTATIONS_PASS_H_