[XLA] Move FusionQueue class declaration into separate header

PiperOrigin-RevId: 215783391

4 files changed, 64 insertions, 27 deletions

diff --git a/tensorflow/compiler/xla/service/BUILD b/tensorflow/compiler/xla/service/BUILD
index f329a27e14..2f8bab0614 100644
--- a/tensorflow/compiler/xla/service/BUILD
+++ b/tensorflow/compiler/xla/service/BUILD
@@ -1324,10 +1324,19 @@ cc_library(
 )
 
 cc_library(
+    name = "fusion_queue",
+    hdrs = ["fusion_queue.h"],
+    deps = [
+        ":hlo",
+    ],
+)
+
+cc_library(
     name = "instruction_fusion",
     srcs = ["instruction_fusion.cc"],
     hdrs = ["instruction_fusion.h"],
     deps = [
+        ":fusion_queue",
         ":hlo",
         ":hlo_pass",
         "//tensorflow/compiler/xla:util",
diff --git a/tensorflow/compiler/xla/service/fusion_queue.h b/tensorflow/compiler/xla/service/fusion_queue.h
new file mode 100644
index 0000000000..1208a7dda8
--- /dev/null
+++ b/tensorflow/compiler/xla/service/fusion_queue.h
@@ -0,0 +1,53 @@
+/* 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_FUSION_QUEUE_H_
+#define TENSORFLOW_COMPILER_XLA_SERVICE_FUSION_QUEUE_H_
+
+#include <utility>
+
+#include "tensorflow/compiler/xla/service/hlo_instruction.h"
+
+namespace xla {
+
+// A queue interface that allows implementations to choose fusion candidates in
+// custom order.
+class FusionQueue {
+ public:
+  FusionQueue() = default;
+  virtual ~FusionQueue() = default;
+
+  // Dequeues the next fusion candidates: a consumer and the list of producers
+  // as operand indices.
+  virtual std::pair<HloInstruction*, std::vector<int64>>
+  DequeueNextInstructionAndOperandsToFuseInOrder() = 0;
+
+  // A callback passed to the queue implementation right before the producer is
+  // fused into the consumer.
+  virtual void PreFusion(HloInstruction* producer, HloInstruction* consumer) {}
+
+  // A callback passed to the queue implementation right after the fusion is
+  // created. Note that original_producer could have been destroyed.
+  virtual void OnFusingInstruction(HloInstruction* fusion,
+                                   HloInstruction* original_producer,
+                                   HloInstruction* original_consumer) {}
+
+  // A callback passed to the queue implementation to notify the removal of an
+  // instruction.
+  virtual void RemoveInstruction(HloInstruction* instruction) = 0;
+};
+
+}  // namespace xla
+
+#endif  // TENSORFLOW_COMPILER_XLA_SERVICE_FUSION_QUEUE_H_
diff --git a/tensorflow/compiler/xla/service/instruction_fusion.cc b/tensorflow/compiler/xla/service/instruction_fusion.cc
index 5a99c40df4..69a4c160ee 100644
--- a/tensorflow/compiler/xla/service/instruction_fusion.cc
+++ b/tensorflow/compiler/xla/service/instruction_fusion.cc
@@ -25,6 +25,7 @@ limitations under the License.
 #include "absl/container/flat_hash_map.h"
 #include "absl/memory/memory.h"
 #include "tensorflow/compiler/xla/map_util.h"
+#include "tensorflow/compiler/xla/service/fusion_queue.h"
 #include "tensorflow/compiler/xla/service/hlo_opcode.h"
 #include "tensorflow/core/lib/core/errors.h"
 #include "tensorflow/core/platform/logging.h"
diff --git a/tensorflow/compiler/xla/service/instruction_fusion.h b/tensorflow/compiler/xla/service/instruction_fusion.h
index da2032f6c7..f14c667520 100644
--- a/tensorflow/compiler/xla/service/instruction_fusion.h
+++ b/tensorflow/compiler/xla/service/instruction_fusion.h
@@ -17,6 +17,7 @@ limitations under the License.
 #ifndef TENSORFLOW_COMPILER_XLA_SERVICE_INSTRUCTION_FUSION_H_
 #define TENSORFLOW_COMPILER_XLA_SERVICE_INSTRUCTION_FUSION_H_
 
+#include "tensorflow/compiler/xla/service/fusion_queue.h"
 #include "tensorflow/compiler/xla/service/hlo_computation.h"
 #include "tensorflow/compiler/xla/service/hlo_instruction.h"
 #include "tensorflow/compiler/xla/service/hlo_module.h"
@@ -25,33 +26,6 @@ limitations under the License.
 
 namespace xla {
 
-// A queue interface that allows implementations to choose fusion candidates in
-// custom order.
-class FusionQueue {
- public:
-  FusionQueue() = default;
-  virtual ~FusionQueue() = default;
-
-  // Dequeues the next fusion candidates: a consumer and the list of producers
-  // as operand indices.
-  virtual std::pair<HloInstruction*, std::vector<int64>>
-  DequeueNextInstructionAndOperandsToFuseInOrder() = 0;
-
-  // A callback passed to the queue implementation right before the producer is
-  // fused into the consumer.
-  virtual void PreFusion(HloInstruction* producer, HloInstruction* consumer) {}
-
-  // A callback passed to the queue implementation right after the fusion is
-  // created. Note that original_producer could have been destroyed.
-  virtual void OnFusingInstruction(HloInstruction* fusion,
-                                   HloInstruction* original_producer,
-                                   HloInstruction* original_consumer) {}
-
-  // A callback passed to the queue implementation to notify the removal of an
-  // instruction.
-  virtual void RemoveInstruction(HloInstruction* instruction) = 0;
-};
-
 // HLO pass which performs instruction fusion. Instructions are fused
 // "vertically", meaning producing instructions are fused into their consumers
 // with the intent that the loops which compute their values will be fused in