From a7a97eaf9731017aaaf90347956776fcc0eb7992 Mon Sep 17 00:00:00 2001
From: "A. Unique TensorFlower" <gardener@tensorflow.org>
Date: Fri, 6 Dec 2019 09:26:48 -0800
Subject: [PATCH] Add op stack class for op processing.

PiperOrigin-RevId: 284199882
Change-Id: I6c86c024a03d0677c5b77e0a749f85898fb6f4c1
---
 tensorflow/core/profiler/convert/BUILD      |  8 +++
 tensorflow/core/profiler/convert/op_stack.h | 69 +++++++++++++++++++++
 2 files changed, 77 insertions(+)
 create mode 100644 tensorflow/core/profiler/convert/op_stack.h

diff --git a/tensorflow/core/profiler/convert/BUILD b/tensorflow/core/profiler/convert/BUILD
index 51af083ca5b..cfb50111c1b 100644
--- a/tensorflow/core/profiler/convert/BUILD
+++ b/tensorflow/core/profiler/convert/BUILD
@@ -15,6 +15,14 @@ cc_library(
     ],
 )
 
+cc_library(
+    name = "op_stack",
+    hdrs = ["op_stack.h"],
+    deps = [
+        "//tensorflow/core:lib",
+    ],
+)
+
 cc_library(
     name = "op_stats_to_tf_stats",
     srcs = ["op_stats_to_tf_stats.cc"],
diff --git a/tensorflow/core/profiler/convert/op_stack.h b/tensorflow/core/profiler/convert/op_stack.h
new file mode 100644
index 00000000000..6bfa4d77643
--- /dev/null
+++ b/tensorflow/core/profiler/convert/op_stack.h
@@ -0,0 +1,69 @@
+/* Copyright 2019 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_CORE_PROFILER_CONVERT_OP_STACK_H_
+#define TENSORFLOW_CORE_PROFILER_CONVERT_OP_STACK_H_
+
+#include <memory>
+#include <utility>
+#include <vector>
+
+#include "tensorflow/core/platform/types.h"
+
+namespace tensorflow {
+namespace profiler {
+
+template <typename OpInfo>
+class OpStack {
+ public:
+  // Pushes an Op onto the stack.
+  void Push(uint32 op_id, std::unique_ptr<OpInfo> op_info) {
+    stack_.emplace_back(op_id, std::move(op_info));
+  }
+
+  // Pops the Op with the given op_id from the stack.
+  std::unique_ptr<OpInfo> Pop(uint32 op_id) {
+    // Pop until match or stack_ is empty.
+    std::unique_ptr<OpInfo> result;
+    while (!stack_.empty()) {
+      auto back = std::move(stack_.back());
+      stack_.pop_back();
+      if (op_id == back.first) {
+        result = std::move(back.second);
+        break;
+      }
+    }
+    return result;
+  }
+
+  // Returns the Op at the top of the stack.
+  OpInfo* Top() const {
+    return stack_.empty() ? nullptr : stack_.back().second.get();
+  }
+
+  // Returns true if the stack is empty.
+  bool Empty() const { return stack_.empty(); }
+
+  // Clears the stack.
+  void Clear() { stack_.clear(); }
+
+ private:
+  std::vector<std::pair<uint32 /*op_id*/, std::unique_ptr<OpInfo>>> stack_;
+};
+
+}  // namespace profiler
+}  // namespace tensorflow
+
+#endif  // TENSORFLOW_CORE_PROFILER_CONVERT_OP_STACK_H_