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/***************************************************************************************************
 * Copyright (c) 2017 - 2025 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
 * SPDX-License-Identifier: BSD-3-Clause
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright notice, this
 * list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright notice,
 * this list of conditions and the following disclaimer in the documentation
 * and/or other materials provided with the distribution.
 *
 * 3. Neither the name of the copyright holder nor the names of its
 * contributors may be used to endorse or promote products derived from
 * this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 **************************************************************************************************/
/*! \file
    \brief Statically sized array of elements that accommodates all CUTLASS-supported numeric types
           and is safe to use in a union.
*/

#pragma once

#include "cutlass/cutlass.h"
#include "cutlass/array.h"
#include "cutlass/platform/platform.h"

namespace cutlass {

////////////////////////////////////////////////////////////////////////////////////////////////////

/// Statically sized array for any data type
template <
  typename T,
  int N
>
struct Array<T, N, false> {
  static constexpr int kSizeBits = sizeof_bits<T>::value * N;

  /// Storage type
  using Storage = typename platform::conditional<
    ((kSizeBits % 32) != 0),
    typename platform::conditional<
      ((kSizeBits % 16) != 0),
      uint8_t,
      uint16_t
    >::type,
    uint32_t
  >::type;

  /// Element type
  using Element = T;

  /// Number of logical elements per stored object
  static constexpr int kElementsPerStoredItem = int(sizeof(Storage) * 8) / sizeof_bits<T>::value;

  /// Number of storage elements
  static constexpr size_t kStorageElements = (N + kElementsPerStoredItem - 1) / kElementsPerStoredItem;

  /// Number of logical elements
  static constexpr size_t kElements = N;

  /// Bitmask for covering one item
  static constexpr Storage kMask = ((Storage(1) << sizeof_bits<T>::value) - 1);

  //
  // C++ standard members with pointer types removed
  //

  typedef T value_type;
  typedef size_t size_type;
  typedef ptrdiff_t difference_type;
  typedef value_type *pointer;
  typedef value_type const *const_pointer;

  //
  // References
  //

  /// Reference object inserts or extracts sub-byte items
  class reference {
    /// Pointer to storage element
    Storage *ptr_{nullptr};

    /// Index into elements packed into Storage object
    int idx_{0};

  public:

    reference() = default;

    /// Ctor
    CUTLASS_HOST_DEVICE
    reference(Storage *ptr, int idx = 0): ptr_(ptr), idx_(idx) { }

    /// Assignment
    CUTLASS_HOST_DEVICE
    reference &operator=(T x) {
    // `*ptr_ & kUpdateMask` will read ptr_ before write to it
    // This means code pattern like
    //
    // ```cpp
    // Array<half_t, N> result;
    // result[0] = xxx;
    // ```
    // 
    // Will leads to compiler warning on use of unintialized member variable. Although we know
    //      this read of uninitialized member variable is harmeless.

#if defined(__clang__)
#  pragma clang diagnostic push
#  pragma clang diagnostic ignored "-Wuninitialized"
#elif defined(__GNUC__)
#  pragma GCC diagnostic push
#  pragma GCC diagnostic ignored "-Wuninitialized"
#  pragma GCC diagnostic ignored "-Wmaybe-uninitialized"
#endif

      Storage item = (reinterpret_cast<Storage const &>(x) & kMask);

      Storage kUpdateMask = Storage(~(kMask << (idx_ * sizeof_bits<T>::value)));

      *ptr_ = Storage(((*ptr_ & kUpdateMask) | (item << idx_ * sizeof_bits<T>::value)));

#if defined(__clang__)
#  pragma clang diagnostic pop
#elif defined(__GNUC__)
#  pragma GCC diagnostic pop
#endif

      return *this;
    }

    CUTLASS_HOST_DEVICE
    T get() const {
      Storage item = Storage((*ptr_ >> (idx_ * sizeof_bits<T>::value)) & kMask);
      return reinterpret_cast<T const &>(item);
    }

    /// Extract
    CUTLASS_HOST_DEVICE
    operator T() const {
      return get();
    }

    /// Explicit cast to int
    CUTLASS_HOST_DEVICE
    explicit operator int() const {
      return int(get());
    }

    /// Explicit cast to float
    CUTLASS_HOST_DEVICE
    explicit operator float() const {
      return float(get());
    }
  };

  /// Reference object extracts sub-byte items
  class const_reference {

    /// Pointer to storage element
    Storage const *ptr_{nullptr};

    /// Index into elements packed into Storage object
    int idx_{0};

  public:

    const_reference() = default;

    /// Ctor
    CUTLASS_HOST_DEVICE
    const_reference(Storage const *ptr, int idx = 0): ptr_(ptr), idx_(idx) { }

    CUTLASS_HOST_DEVICE
    const T get() const {
      Storage item = (*ptr_ >> (idx_ * sizeof_bits<T>::value)) & kMask;
      return reinterpret_cast<T const &>(item);
    }

    /// Extract
    CUTLASS_HOST_DEVICE
    operator T() const {
      Storage item = Storage(Storage(*ptr_ >> Storage(idx_ * sizeof_bits<T>::value)) & kMask);
      return reinterpret_cast<T const &>(item);
    }

    /// Explicit cast to int
    CUTLASS_HOST_DEVICE
    explicit operator int() const {
      return int(get());
    }

    /// Explicit cast to float
    CUTLASS_HOST_DEVICE
    explicit operator float() const {
      return float(get());
    }
  };

  //
  // Iterators
  //

  /// Bidirectional iterator over elements
  class iterator {

    /// Pointer to storage element
    Storage *ptr_{nullptr};

    /// Index into elements packed into Storage object
    int idx_{0};

  public:

    iterator() = default;

    CUTLASS_HOST_DEVICE
    iterator(Storage *ptr, int idx = 0): ptr_(ptr), idx_(idx) { }

    CUTLASS_HOST_DEVICE
    iterator &operator++() {
      ++idx_;
      if (idx_ == kElementsPerStoredItem) {
        ++ptr_;
        idx_ = 0;
      }
      return *this;
    }

    CUTLASS_HOST_DEVICE
    iterator &operator--() {
      if (!idx_) {
        --ptr_;
        idx_ = kElementsPerStoredItem - 1;
      }
      else {
        --idx_;
      }
      return *this;
    }

    CUTLASS_HOST_DEVICE
    iterator operator++(int) {
      iterator ret(*this);
      ++idx_;
      if (idx_ == kElementsPerStoredItem) {
        ++ptr_;
        idx_ = 0;
      }
      return ret;
    }

    CUTLASS_HOST_DEVICE
    iterator operator--(int) {
      iterator ret(*this);
      if (!idx_) {
        --ptr_;
        idx_ = kElementsPerStoredItem - 1;
      }
      else {
        --idx_;
      }
      return ret;
    }

    CUTLASS_HOST_DEVICE
    reference operator*() const {
      return reference(ptr_, idx_);
    }

    CUTLASS_HOST_DEVICE
    bool operator==(iterator const &other) const {
      return ptr_ == other.ptr_ && idx_ == other.idx_;
    }

    CUTLASS_HOST_DEVICE
    bool operator!=(iterator const &other) const {
      return !(*this == other);
    }
  };

  /// Bidirectional constant iterator over elements
  class const_iterator {

    /// Pointer to storage element
    Storage const *ptr_{nullptr};

    /// Index into elements packed into Storage object
    int idx_{0};

  public:

    const_iterator() = default;

    CUTLASS_HOST_DEVICE
    const_iterator(Storage const *ptr, int idx = 0): ptr_(ptr), idx_(idx) { }

    CUTLASS_HOST_DEVICE
    iterator &operator++() {
      ++idx_;
      if (idx_ == kElementsPerStoredItem) {
        ++ptr_;
        idx_ = 0;
      }
      return *this;
    }

    CUTLASS_HOST_DEVICE
    iterator &operator--() {
      if (!idx_) {
        --ptr_;
        idx_ = kElementsPerStoredItem - 1;
      }
      else {
        --idx_;
      }
      return *this;
    }

    CUTLASS_HOST_DEVICE
    iterator operator++(int) {
      iterator ret(*this);
      ++idx_;
      if (idx_ == kElementsPerStoredItem) {
        ++ptr_;
        idx_ = 0;
      }
      return ret;
    }

    CUTLASS_HOST_DEVICE
    iterator operator--(int) {
      iterator ret(*this);
      if (!idx_) {
        --ptr_;
        idx_ = kElementsPerStoredItem - 1;
      }
      else {
        --idx_;
      }
      return ret;
    }

    CUTLASS_HOST_DEVICE
    const_reference operator*() const {
      return const_reference(ptr_, idx_);
    }

    CUTLASS_HOST_DEVICE
    bool operator==(iterator const &other) const {
      return ptr_ == other.ptr_ && idx_ == other.idx_;
    }

    CUTLASS_HOST_DEVICE
    bool operator!=(iterator const &other) const {
      return !(*this == other);
    }
  };

  /// Bidirectional iterator over elements
  class reverse_iterator {

    /// Pointer to storage element
    Storage *ptr_{nullptr};

    /// Index into elements packed into Storage object
    int idx_{0};

  public:

    reverse_iterator() = default;

    CUTLASS_HOST_DEVICE
    reverse_iterator(Storage *ptr, int idx = 0): ptr_(ptr), idx_(idx) { }
  };

  /// Bidirectional constant iterator over elements
  class const_reverse_iterator {

    /// Pointer to storage element
    Storage const *ptr_{nullptr};

    /// Index into elements packed into Storage object
    int idx_{0};

  public:

    const_reverse_iterator() = default;

    CUTLASS_HOST_DEVICE
    const_reverse_iterator(Storage const *ptr, int idx = 0): ptr_(ptr), idx_(idx) { }
  };

  /// Efficient clear method
  CUTLASS_HOST_DEVICE
  void clear() {

    CUTLASS_PRAGMA_UNROLL
    for (int i = 0; i < int(kStorageElements); ++i) {
      storage[i] = Storage(0);
    }
  }

  CUTLASS_HOST_DEVICE
  reference at(size_type pos) {
    return reference(storage + pos / kElementsPerStoredItem, pos % kElementsPerStoredItem);
  }

  CUTLASS_HOST_DEVICE
  const_reference at(size_type pos) const {
    return const_reference(storage + pos / kElementsPerStoredItem, pos % kElementsPerStoredItem);
  }

  CUTLASS_HOST_DEVICE
  reference operator[](size_type pos) {
    return at(pos);
  }

  CUTLASS_HOST_DEVICE
  const_reference operator[](size_type pos) const {
    return at(pos);
  }

  CUTLASS_HOST_DEVICE
  reference front() {
    return at(0);
  }

  CUTLASS_HOST_DEVICE
  const_reference front() const {
    return at(0);
  }

  CUTLASS_HOST_DEVICE
  reference back() {
    return reference(storage + kStorageElements - 1, kElementsPerStoredItem - 1);
  }

  CUTLASS_HOST_DEVICE
  const_reference back() const {
    return const_reference(storage + kStorageElements - 1, kElementsPerStoredItem - 1);
  }

  CUTLASS_HOST_DEVICE
  pointer data() {
    return reinterpret_cast<pointer>(storage);
  }

  CUTLASS_HOST_DEVICE
  const_pointer data() const {
    return reinterpret_cast<const_pointer>(storage);
  }
  
  CUTLASS_HOST_DEVICE
  Storage * raw_data() {
    return storage;
  }

  CUTLASS_HOST_DEVICE
  Storage const * raw_data() const {
    return storage;
  }

  CUTLASS_HOST_DEVICE
  constexpr bool empty() const {
    return !kElements;
  }

  CUTLASS_HOST_DEVICE
  constexpr size_type size() const {
    return kElements;
  }

  CUTLASS_HOST_DEVICE
  constexpr size_type max_size() const {
    return kElements;
  }

  CUTLASS_HOST_DEVICE
  void fill(T const &value) {

    CUTLASS_PRAGMA_UNROLL
    for (int i = 0; i < kElementsPerStoredItem; ++i) {
      reference ref(storage, i);
      ref = value;
    }

    CUTLASS_PRAGMA_UNROLL
    for (int i = 1; i < kStorageElements; ++i) {
      storage[i] = storage[0];
    }
  }

  CUTLASS_HOST_DEVICE
  iterator begin() {
    return iterator(storage);
  }

  CUTLASS_HOST_DEVICE
  const_iterator cbegin() const {
    return const_iterator(storage);
  }

  CUTLASS_HOST_DEVICE
  iterator end() {
    return iterator(storage + kStorageElements);
  }

  CUTLASS_HOST_DEVICE
  const_iterator cend() const {
    return const_iterator(storage + kStorageElements);
  }

  CUTLASS_HOST_DEVICE
  reverse_iterator rbegin() {
    return reverse_iterator(storage + kStorageElements);
  }

  CUTLASS_HOST_DEVICE
  const_reverse_iterator crbegin() const {
    return const_reverse_iterator(storage + kStorageElements);
  }

  CUTLASS_HOST_DEVICE
  reverse_iterator rend() {
    return reverse_iterator(storage);
  }

  CUTLASS_HOST_DEVICE
  const_reverse_iterator crend() const {
    return const_reverse_iterator(storage);
  }

private:
  /// Internal storage
  Storage storage[kStorageElements];
};

////////////////////////////////////////////////////////////////////////////////////////////////////

////////////////////////////////////////////////////////////////////////////////////////////////////

} // namespace cutlass

////////////////////////////////////////////////////////////////////////////////////////////////////

	/***************************************************************************************************
	* Copyright (c) 2017 - 2025 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
	* SPDX-License-Identifier: BSD-3-Clause
	*
	* Redistribution and use in source and binary forms, with or without
	* modification, are permitted provided that the following conditions are met:
	*
	* 1. Redistributions of source code must retain the above copyright notice, this
	* list of conditions and the following disclaimer.
	*
	* 2. Redistributions in binary form must reproduce the above copyright notice,
	* this list of conditions and the following disclaimer in the documentation
	* and/or other materials provided with the distribution.
	*
	* 3. Neither the name of the copyright holder nor the names of its
	* contributors may be used to endorse or promote products derived from
	* this software without specific prior written permission.
	*
	* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
	* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
	* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
	* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
	* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
	* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
	* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
	* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
	*
	**************************************************************************************************/
	/*! \file
	\brief Statically sized array of elements that accommodates all CUTLASS-supported numeric types
	and is safe to use in a union.
	*/

	#pragma once

	#include "cutlass/cutlass.h"
	#include "cutlass/array.h"
	#include "cutlass/platform/platform.h"

	namespace cutlass {

	////////////////////////////////////////////////////////////////////////////////////////////////////

	/// Statically sized array for any data type
	template <
	typename T,
	int N
	>
	struct Array<T, N, false> {
	static constexpr int kSizeBits = sizeof_bits<T>::value * N;

	/// Storage type
	using Storage = typename platform::conditional<
	((kSizeBits % 32) != 0),
	typename platform::conditional<
	((kSizeBits % 16) != 0),
	uint8_t,
	uint16_t
	>::type,
	uint32_t
	>::type;

	/// Element type
	using Element = T;

	/// Number of logical elements per stored object
	static constexpr int kElementsPerStoredItem = int(sizeof(Storage) * 8) / sizeof_bits<T>::value;

	/// Number of storage elements
	static constexpr size_t kStorageElements = (N + kElementsPerStoredItem - 1) / kElementsPerStoredItem;

	/// Number of logical elements
	static constexpr size_t kElements = N;

	/// Bitmask for covering one item
	static constexpr Storage kMask = ((Storage(1) << sizeof_bits<T>::value) - 1);

	//
	// C++ standard members with pointer types removed
	//

	typedef T value_type;
	typedef size_t size_type;
	typedef ptrdiff_t difference_type;
	typedef value_type *pointer;
	typedef value_type const *const_pointer;

	//
	// References
	//

	/// Reference object inserts or extracts sub-byte items
	class reference {
	/// Pointer to storage element
	Storage *ptr_{nullptr};

	/// Index into elements packed into Storage object
	int idx_{0};

	public:

	reference() = default;

	/// Ctor
	CUTLASS_HOST_DEVICE
	reference(Storage *ptr, int idx = 0): ptr_(ptr), idx_(idx) { }

	/// Assignment
	CUTLASS_HOST_DEVICE
	reference &operator=(T x) {
	// `*ptr_ & kUpdateMask` will read ptr_ before write to it
	// This means code pattern like
	//
	// ```cpp
	// Array<half_t, N> result;
	// result[0] = xxx;
	// ```
	//
	// Will leads to compiler warning on use of unintialized member variable. Although we know
	// this read of uninitialized member variable is harmeless.

	#if defined(__clang__)
	# pragma clang diagnostic push
	# pragma clang diagnostic ignored "-Wuninitialized"
	#elif defined(__GNUC__)
	# pragma GCC diagnostic push
	# pragma GCC diagnostic ignored "-Wuninitialized"
	# pragma GCC diagnostic ignored "-Wmaybe-uninitialized"
	#endif

	Storage item = (reinterpret_cast<Storage const &>(x) & kMask);

	Storage kUpdateMask = Storage(~(kMask << (idx_ * sizeof_bits<T>::value)));

	ptr_ = Storage(((ptr_ & kUpdateMask) \| (item << idx_ * sizeof_bits<T>::value)));

	#if defined(__clang__)
	# pragma clang diagnostic pop
	#elif defined(__GNUC__)
	# pragma GCC diagnostic pop
	#endif

	return *this;
	}

	CUTLASS_HOST_DEVICE
	T get() const {
	Storage item = Storage((ptr_ >> (idx_ sizeof_bits<T>::value)) & kMask);
	return reinterpret_cast<T const &>(item);
	}

	/// Extract
	CUTLASS_HOST_DEVICE
	operator T() const {
	return get();
	}

	/// Explicit cast to int
	CUTLASS_HOST_DEVICE
	explicit operator int() const {
	return int(get());
	}

	/// Explicit cast to float
	CUTLASS_HOST_DEVICE
	explicit operator float() const {
	return float(get());
	}
	};

	/// Reference object extracts sub-byte items
	class const_reference {

	/// Pointer to storage element
	Storage const *ptr_{nullptr};

	/// Index into elements packed into Storage object
	int idx_{0};

	public:

	const_reference() = default;

	/// Ctor
	CUTLASS_HOST_DEVICE
	const_reference(Storage const *ptr, int idx = 0): ptr_(ptr), idx_(idx) { }

	CUTLASS_HOST_DEVICE
	const T get() const {
	Storage item = (ptr_ >> (idx_ sizeof_bits<T>::value)) & kMask;
	return reinterpret_cast<T const &>(item);
	}

	/// Extract
	CUTLASS_HOST_DEVICE
	operator T() const {
	Storage item = Storage(Storage(ptr_ >> Storage(idx_ sizeof_bits<T>::value)) & kMask);
	return reinterpret_cast<T const &>(item);
	}

	/// Explicit cast to int
	CUTLASS_HOST_DEVICE
	explicit operator int() const {
	return int(get());
	}

	/// Explicit cast to float
	CUTLASS_HOST_DEVICE
	explicit operator float() const {
	return float(get());
	}
	};

	//
	// Iterators
	//

	/// Bidirectional iterator over elements
	class iterator {

	/// Pointer to storage element
	Storage *ptr_{nullptr};

	/// Index into elements packed into Storage object
	int idx_{0};

	public:

	iterator() = default;

	CUTLASS_HOST_DEVICE
	iterator(Storage *ptr, int idx = 0): ptr_(ptr), idx_(idx) { }

	CUTLASS_HOST_DEVICE
	iterator &operator++() {
	++idx_;
	if (idx_ == kElementsPerStoredItem) {
	++ptr_;
	idx_ = 0;
	}
	return *this;
	}

	CUTLASS_HOST_DEVICE
	iterator &operator--() {
	if (!idx_) {
	--ptr_;
	idx_ = kElementsPerStoredItem - 1;
	}
	else {
	--idx_;
	}
	return *this;
	}

	CUTLASS_HOST_DEVICE
	iterator operator++(int) {
	iterator ret(*this);
	++idx_;
	if (idx_ == kElementsPerStoredItem) {
	++ptr_;
	idx_ = 0;
	}
	return ret;
	}

	CUTLASS_HOST_DEVICE
	iterator operator--(int) {
	iterator ret(*this);
	if (!idx_) {
	--ptr_;
	idx_ = kElementsPerStoredItem - 1;
	}
	else {
	--idx_;
	}
	return ret;
	}

	CUTLASS_HOST_DEVICE
	reference operator*() const {
	return reference(ptr_, idx_);
	}

	CUTLASS_HOST_DEVICE
	bool operator==(iterator const &other) const {
	return ptr_ == other.ptr_ && idx_ == other.idx_;
	}

	CUTLASS_HOST_DEVICE
	bool operator!=(iterator const &other) const {
	return !(*this == other);
	}
	};

	/// Bidirectional constant iterator over elements
	class const_iterator {

	/// Pointer to storage element
	Storage const *ptr_{nullptr};

	/// Index into elements packed into Storage object
	int idx_{0};

	public:

	const_iterator() = default;

	CUTLASS_HOST_DEVICE
	const_iterator(Storage const *ptr, int idx = 0): ptr_(ptr), idx_(idx) { }

	CUTLASS_HOST_DEVICE
	iterator &operator++() {
	++idx_;
	if (idx_ == kElementsPerStoredItem) {
	++ptr_;
	idx_ = 0;
	}
	return *this;
	}

	CUTLASS_HOST_DEVICE
	iterator &operator--() {
	if (!idx_) {
	--ptr_;
	idx_ = kElementsPerStoredItem - 1;
	}
	else {
	--idx_;
	}
	return *this;
	}

	CUTLASS_HOST_DEVICE
	iterator operator++(int) {
	iterator ret(*this);
	++idx_;
	if (idx_ == kElementsPerStoredItem) {
	++ptr_;
	idx_ = 0;
	}
	return ret;
	}

	CUTLASS_HOST_DEVICE
	iterator operator--(int) {
	iterator ret(*this);
	if (!idx_) {
	--ptr_;
	idx_ = kElementsPerStoredItem - 1;
	}
	else {
	--idx_;
	}
	return ret;
	}

	CUTLASS_HOST_DEVICE
	const_reference operator*() const {
	return const_reference(ptr_, idx_);
	}

	CUTLASS_HOST_DEVICE
	bool operator==(iterator const &other) const {
	return ptr_ == other.ptr_ && idx_ == other.idx_;
	}

	CUTLASS_HOST_DEVICE
	bool operator!=(iterator const &other) const {
	return !(*this == other);
	}
	};

	/// Bidirectional iterator over elements
	class reverse_iterator {

	/// Pointer to storage element
	Storage *ptr_{nullptr};

	/// Index into elements packed into Storage object
	int idx_{0};

	public:

	reverse_iterator() = default;

	CUTLASS_HOST_DEVICE
	reverse_iterator(Storage *ptr, int idx = 0): ptr_(ptr), idx_(idx) { }
	};

	/// Bidirectional constant iterator over elements
	class const_reverse_iterator {

	/// Pointer to storage element
	Storage const *ptr_{nullptr};

	/// Index into elements packed into Storage object
	int idx_{0};

	public:

	const_reverse_iterator() = default;

	CUTLASS_HOST_DEVICE
	const_reverse_iterator(Storage const *ptr, int idx = 0): ptr_(ptr), idx_(idx) { }
	};

	/// Efficient clear method
	CUTLASS_HOST_DEVICE
	void clear() {

	CUTLASS_PRAGMA_UNROLL
	for (int i = 0; i < int(kStorageElements); ++i) {
	storage[i] = Storage(0);
	}
	}

	CUTLASS_HOST_DEVICE
	reference at(size_type pos) {
	return reference(storage + pos / kElementsPerStoredItem, pos % kElementsPerStoredItem);
	}

	CUTLASS_HOST_DEVICE
	const_reference at(size_type pos) const {
	return const_reference(storage + pos / kElementsPerStoredItem, pos % kElementsPerStoredItem);
	}

	CUTLASS_HOST_DEVICE
	reference operator[](size_type pos) {
	return at(pos);
	}

	CUTLASS_HOST_DEVICE
	const_reference operator[](size_type pos) const {
	return at(pos);
	}

	CUTLASS_HOST_DEVICE
	reference front() {
	return at(0);
	}

	CUTLASS_HOST_DEVICE
	const_reference front() const {
	return at(0);
	}

	CUTLASS_HOST_DEVICE
	reference back() {
	return reference(storage + kStorageElements - 1, kElementsPerStoredItem - 1);
	}

	CUTLASS_HOST_DEVICE
	const_reference back() const {
	return const_reference(storage + kStorageElements - 1, kElementsPerStoredItem - 1);
	}

	CUTLASS_HOST_DEVICE
	pointer data() {
	return reinterpret_cast<pointer>(storage);
	}

	CUTLASS_HOST_DEVICE
	const_pointer data() const {
	return reinterpret_cast<const_pointer>(storage);
	}

	CUTLASS_HOST_DEVICE
	Storage * raw_data() {
	return storage;
	}

	CUTLASS_HOST_DEVICE
	Storage const * raw_data() const {
	return storage;
	}

	CUTLASS_HOST_DEVICE
	constexpr bool empty() const {
	return !kElements;
	}

	CUTLASS_HOST_DEVICE
	constexpr size_type size() const {
	return kElements;
	}

	CUTLASS_HOST_DEVICE
	constexpr size_type max_size() const {
	return kElements;
	}

	CUTLASS_HOST_DEVICE
	void fill(T const &value) {

	CUTLASS_PRAGMA_UNROLL
	for (int i = 0; i < kElementsPerStoredItem; ++i) {
	reference ref(storage, i);
	ref = value;
	}

	CUTLASS_PRAGMA_UNROLL
	for (int i = 1; i < kStorageElements; ++i) {
	storage[i] = storage[0];
	}
	}

	CUTLASS_HOST_DEVICE
	iterator begin() {
	return iterator(storage);
	}

	CUTLASS_HOST_DEVICE
	const_iterator cbegin() const {
	return const_iterator(storage);
	}

	CUTLASS_HOST_DEVICE
	iterator end() {
	return iterator(storage + kStorageElements);
	}

	CUTLASS_HOST_DEVICE
	const_iterator cend() const {
	return const_iterator(storage + kStorageElements);
	}

	CUTLASS_HOST_DEVICE
	reverse_iterator rbegin() {
	return reverse_iterator(storage + kStorageElements);
	}

	CUTLASS_HOST_DEVICE
	const_reverse_iterator crbegin() const {
	return const_reverse_iterator(storage + kStorageElements);
	}

	CUTLASS_HOST_DEVICE
	reverse_iterator rend() {
	return reverse_iterator(storage);
	}

	CUTLASS_HOST_DEVICE
	const_reverse_iterator crend() const {
	return const_reverse_iterator(storage);
	}

	private:
	/// Internal storage
	Storage storage[kStorageElements];
	};

	////////////////////////////////////////////////////////////////////////////////////////////////////

	////////////////////////////////////////////////////////////////////////////////////////////////////

	} // namespace cutlass

	////////////////////////////////////////////////////////////////////////////////////////////////////