cutlass/include/cutlass/numeric_size.h

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/*!
    \file
    \brief Top-level include for all CUTLASS numeric types.
*/

#pragma once

#include "cutlass/cutlass.h"

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

namespace cutlass {

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

/// Defines the size of an element in bits
template <typename T>
struct sizeof_bits {
  static constexpr int value = int(sizeof(T) * 8);
};

template <typename T>
struct sizeof_bits<T const>: sizeof_bits<T> {};

template <>
struct sizeof_bits<void> {
  static constexpr int value = 0;
};

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

/// Returns the number of bytes required to hold a specified number of bits
template <class R = int, class T>
CUTLASS_HOST_DEVICE
constexpr
R
bits_to_bytes(T bits) {
  return (R(bits) + R(7)) / R(8);
}

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

template <class T>
struct is_subbyte {
  static constexpr bool value = sizeof_bits<T>::value < 8;
};

template <class T>
struct is_subbyte<T const> : is_subbyte<T> {};

}  // namespace cutlass

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