From f915b7ca8b1812b15c188ef8acc7bf7257d3255f Mon Sep 17 00:00:00 2001
From: =?utf8?q?=EB=B0=95=EC=A2=85=ED=98=84/=EB=8F=99=EC=9E=91=EC=A0=9C?=
 =?utf8?q?=EC=96=B4Lab=28SR=29/Staff=20Engineer/=EC=82=BC=EC=84=B1?=
 =?utf8?q?=EC=A0=84=EC=9E=90?= <jh1302.park@samsung.com>
Date: Thu, 26 Jul 2018 08:17:10 +0900
Subject: [PATCH] [nest] Introduce 'Level' class (#800)

This commit introduces 'Level' class in nest IR which represents the
(iteration) level of each iteration variables.

Signed-off-by: Jonghyun Park <jh1302.park@samsung.com>
---
 contrib/nest/include/nest/Level.h | 29 +++++++++++++++++++++++++++++
 contrib/nest/src/Level.cpp        | 32 ++++++++++++++++++++++++++++++++
 contrib/nest/src/Level.test.cpp   | 23 +++++++++++++++++++++++
 3 files changed, 84 insertions(+)
 create mode 100644 contrib/nest/include/nest/Level.h
 create mode 100644 contrib/nest/src/Level.cpp
 create mode 100644 contrib/nest/src/Level.test.cpp

diff --git a/contrib/nest/include/nest/Level.h b/contrib/nest/include/nest/Level.h
new file mode 100644
index 0000000..7d92d80
--- /dev/null
+++ b/contrib/nest/include/nest/Level.h
@@ -0,0 +1,29 @@
+#ifndef __NEST_LEVEL_H__
+#define __NEST_LEVEL_H__
+
+#include <cstdint>
+
+namespace nest
+{
+class Level final
+{
+public:
+  Level();
+  explicit Level(uint32_t value);
+
+public:
+  bool valid(void) const;
+
+public:
+  uint32_t value(void) const { return _value; }
+
+private:
+  uint32_t _value;
+};
+
+bool operator==(const Level &lhs, const Level &rhs);
+bool operator<(const Level &lhs, const Level &rhs);
+
+} // namespace nest
+
+#endif // __NEST_LEVEL_H__
diff --git a/contrib/nest/src/Level.cpp b/contrib/nest/src/Level.cpp
new file mode 100644
index 0000000..e7b6ef7
--- /dev/null
+++ b/contrib/nest/src/Level.cpp
@@ -0,0 +1,32 @@
+#include "nest/Level.h"
+
+#include <cassert>
+
+namespace
+{
+const uint32_t invalid_tag = 0xffffffff;
+} // namespace
+
+namespace nest
+{
+Level::Level() : _value{invalid_tag}
+{
+  // DO NOTHING
+}
+
+Level::Level(uint32_t value) : _value{value} { assert(value != invalid_tag); }
+
+bool Level::valid(void) const { return _value != invalid_tag; }
+
+bool operator==(const Level &lhs, const Level &rhs)
+{
+  assert(lhs.valid() && rhs.valid());
+  return lhs.value() == rhs.value();
+}
+
+bool operator<(const Level &lhs, const Level &rhs)
+{
+  assert(lhs.valid() && rhs.valid());
+  return lhs.value() < rhs.value();
+}
+} // namespace nest
diff --git a/contrib/nest/src/Level.test.cpp b/contrib/nest/src/Level.test.cpp
new file mode 100644
index 0000000..f99a2f5
--- /dev/null
+++ b/contrib/nest/src/Level.test.cpp
@@ -0,0 +1,23 @@
+#include "nest/Level.h"
+
+#include <gtest/gtest.h>
+
+TEST(LEVEL, constructor)
+{
+  nest::Level lv{3};
+
+  ASSERT_EQ(lv.value(), 3);
+}
+
+TEST(LEVEL, operator_eq)
+{
+  ASSERT_TRUE(nest::Level(3) == nest::Level(3));
+  ASSERT_FALSE(nest::Level(3) == nest::Level(4));
+}
+
+TEST(LEVEL, operator_lt)
+{
+  ASSERT_FALSE(nest::Level(3) < nest::Level(3));
+  ASSERT_TRUE(nest::Level(3) < nest::Level(4));
+  ASSERT_FALSE(nest::Level(4) < nest::Level(3));
+}
-- 
2.7.4