1 files changed, 100 insertions, 0 deletions
diff --git a/compiler/angkor/src/ADT/tensor/IndexEnumerator.cpp b/compiler/angkor/src/ADT/tensor/IndexEnumerator.cpp
new file mode 100644
index 000000000..623313a2e
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+++ b/compiler/angkor/src/ADT/tensor/IndexEnumerator.cpp
@@ -0,0 +1,100 @@
+/*
+ * Copyright (c) 2018 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 "nncc/core/ADT/tensor/IndexEnumerator.h"
+
+#include <cassert>
+
+using nncc::core::ADT::tensor::Shape;
+
+inline uint32_t axis_of(const Shape &shape, uint32_t cursor)
+{
+  const uint32_t rank = shape.rank();
+  assert(cursor < rank);
+  return rank - cursor - 1;
+}
+
+namespace nncc
+{
+namespace core
+{
+namespace ADT
+{
+namespace tensor
+{
+
+IndexEnumerator::IndexEnumerator(const Shape &shape) : _shape{shape}, _cursor(0)
+{
+  const uint32_t rank = _shape.rank();
+
+  // Initialize _index
+  _index.resize(rank);
+  for (uint32_t axis = 0; axis < rank; ++axis)
+  {
+    _index.at(axis) = 0;
+  }
+
+  // Initialize _cursor
+  for (_cursor = 0; _cursor < rank; ++_cursor)
+  {
+    const auto axis = axis_of(_shape, _cursor);
+
+    if (_index.at(axis) < _shape.dim(axis))
+    {
+      break;
+    }
+  }
+}
+
+void IndexEnumerator::advance(void)
+{
+  const uint32_t rank = _shape.rank();
+
+  // Find axis to be updated
+  while (_cursor < rank)
+  {
+    const auto axis = axis_of(_shape, _cursor);
+
+    if ((_index.at(axis)) + 1 < _shape.dim(axis))
+    {
+      break;
+    }
+
+    ++_cursor;
+  }
+
+  if (_cursor == rank)
+  {
+    return;
+  }
+
+  // Update index
+  _index.at(axis_of(_shape, _cursor)) += 1;
+
+  for (uint32_t pos = 0; pos < _cursor; ++pos)
+  {
+    const auto axis = axis_of(_shape, pos);
+    _index.at(axis) = 0;
+  }
+
+  // Reset cursor
+  _cursor = 0;
+}
+
+} // namespace tensor
+} // namespace ADT
+} // namespace core
+} // namespace nncc