[moco-tf] Canonicalize TFRelu6 (#6193)

This will add Relu6Canonicalizier that transforms TFRelu6 node to canonical ReLU6 node

Signed-off-by: SaeHie Park <saehie.park@samsung.com>

diff --git a/compiler/moco-tf/src/Canonicalization/Relu6Canonicalizer.cpp b/compiler/moco-tf/src/Canonicalization/Relu6Canonicalizer.cpp
new file mode 100644 (file)
index 0000000..0765724
--- /dev/null
+++ b/compiler/moco-tf/src/Canonicalization/Relu6Canonicalizer.cpp
@@ -0,0 +1,89 @@
+/*
+ * Copyright (c) 2019 Samsung Electronics Co., Ltd. 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.
+ */
+
+#include "Relu6Canonicalizer.h"
+
+#include "Dialect/TFDialect.h"
+#include "Dialect/TFNodes.h"
+#include "Dialect/TFNodeVisitor.h"
+#include "Dialect/TFNodeImpl.h"
+
+#include <stdex/Memory.h>
+
+namespace
+{
+
+bool canonicalize_relu6(loco::Graph *graph, moco::tf::TFRelu6 *node)
+{
+  /**
+   * @note This will replace TFRelu6 node with Canonical ReLU6
+   *
+   *       Before
+   *                 A --- TFRelu6 -- C
+   *       After
+   *                    +- TFRelu6 --
+   *                    |
+   *                 A -+- ReLU6 -- C
+   *
+   *       Where
+   *                 A : features of TFRelu6
+   *                 C : a node that uses TFRelu6 as an input
+   *                 TFRelu6 is disconnected from C
+   */
+
+  auto relu6_node = graph->nodes()->create<loco::ReLU6>();
+
+  auto node_A = node->features();
+
+  // update connections
+  relu6_node->input(node_A);
+
+  // replace node
+  replace(node).with(relu6_node);
+
+  return true;
+}
+
+} // namespace
+
+namespace moco
+{
+namespace tf
+{
+
+bool Relu6Canonicalizer::run(loco::Graph *graph)
+{
+  auto active_nodes = loco::active_nodes(loco::output_nodes(graph));
+  bool changed = false;
+
+  for (auto node : active_nodes)
+  {
+    if (node->dialect() == TFDialect::get())
+    {
+      auto tf_node = dynamic_cast<moco::tf::TFRelu6 *>(node);
+      if (tf_node != nullptr)
+      {
+        if (canonicalize_relu6(graph, tf_node))
+          changed = true;
+      }
+    }
+  }
+
+  return changed;
+}
+
+} // namespace tf
+} // namespace moco

diff --git a/compiler/moco-tf/src/Canonicalization/Relu6Canonicalizer.h b/compiler/moco-tf/src/Canonicalization/Relu6Canonicalizer.h
new file mode 100644 (file)
index 0000000..aa1580f
--- /dev/null
+++ b/compiler/moco-tf/src/Canonicalization/Relu6Canonicalizer.h
@@ -0,0 +1,44 @@
+/*
+ * Copyright (c) 2019 Samsung Electronics Co., Ltd. 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 __MOCO_TF_RELU6_CANONICALIZER_H__
+#define __MOCO_TF_RELU6_CANONICALIZER_H__
+
+#include "Transform.h"
+
+#include <loco.h>
+
+namespace moco
+{
+namespace tf
+{
+
+/**
+ * @brief  Convert TFRelu6 to Canonical ReLU6
+ */
+class Relu6Canonicalizer : public Transform
+{
+public:
+  const char *name(void) const final { return "Relu6Canonicalizer"; }
+
+public:
+  bool run(loco::Graph *graph) override;
+};
+
+} // namespace tf
+} // namespace moco
+
+#endif // __MOCO_TF_RELU6_CANONICALIZER_H__