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diff --git a/tensorflow/compiler/xla/service/compilation_cache.h b/tensorflow/compiler/xla/service/compilation_cache.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_SERVICE_COMPILATION_CACHE_H_
+#define TENSORFLOW_COMPILER_XLA_SERVICE_COMPILATION_CACHE_H_
+
+#include <map>
+#include <memory>
+#include <string>
+
+#include "tensorflow/compiler/xla/service/executable.h"
+#include "tensorflow/compiler/xla/service/hlo_module_config.h"
+#include "tensorflow/compiler/xla/service/versioned_computation_handle.h"
+#include "tensorflow/compiler/xla/types.h"
+#include "tensorflow/core/platform/macros.h"
+#include "tensorflow/core/platform/mutex.h"
+#include "tensorflow/core/platform/thread_annotations.h"
+
+namespace xla {
+
+// A cache which stores Executables indexed by computation handle and version.
+class CompilationCache {
+ public:
+  CompilationCache() {}
+
+  // Insert the given Executable into the cache. Return a bare Executable
+  // pointer for the caller to use. Note: the returned pointer will *not* be the
+  // same as the given unique pointer if the computation already exists in the
+  // cache. See comments in the .cc implementation for details of this case.
+  //
+  // module_config is provided by the caller, instead of being taken from the
+  // executable, so that we can insert keys into the compilation cache that are
+  // devoid of layout (where XLA gets to choose what layout to compile).
+  //
+  // A shared_ptr is returned so the caller can keep the Executable from being
+  // destructed in the event that the Executable is evicted from the
+  // computation cache (and the cache's shared_ptr to the Executable is
+  // destructed).
+  std::shared_ptr<Executable> Insert(std::unique_ptr<Executable> executable,
+                                     const HloModuleConfig& module_config);
+
+  // Lookup the Executable for the specified versioned computation in the cache.
+  // Return a shared_ptr to the Executable if it exists in the cache. Return
+  // nullptr otherwise.
+  std::shared_ptr<Executable> LookUp(
+      const VersionedComputationHandle& versioned_handle,
+      const HloModuleConfig& module_config) const;
+
+ protected:
+  mutable tensorflow::mutex mutex_;
+
+  // Map from versioned handle with program layout to Executable built
+  // for that computation version and program layout.
+  using CacheKey = string;
+
+  CacheKey BuildKey(const VersionedComputationHandle& versioned_handle,
+                    const HloModuleConfig& module_config) const;
+  std::map<CacheKey, std::shared_ptr<Executable>> cache_ GUARDED_BY(mutex_);
+
+ private:
+  TF_DISALLOW_COPY_AND_ASSIGN(CompilationCache);
+};
+
+}  // namespace xla
+
+#endif  // TENSORFLOW_COMPILER_XLA_SERVICE_COMPILATION_CACHE_H_