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/*
* Copyright 2002-2019 Intel Corporation.
*
* This software and the related documents are Intel copyrighted materials, and your
* use of them is governed by the express license under which they were provided to
* you ("License"). Unless the License provides otherwise, you may not use, modify,
* copy, publish, distribute, disclose or transmit this software or the related
* documents without Intel's prior written permission.
*
* This software and the related documents are provided as is, with no express or
* implied warranties, other than those that are expressly stated in the License.
*/
// <COMPONENT>: util
// <FILE-TYPE>: component public header
#ifndef UTIL_NUMBERBITS_HPP
#define UTIL_NUMBERBITS_HPP
namespace UTIL {
/*! @brief Compute the number of bits required to hold a constant integer value.
*
* This can be used to compute the number of bits required to hold an integer (up to a
* 32-bit integer). Usage is like this:
*
* \code
* int nbits = NUMBER_BITS<54>::count; // number of bits required to hold "54"
* \endcode
*
* Note, the value computed is a compile-time constant, so it can be used wherever
* a constant is allowed:
* \code
* struct FOO
* {
* int a : NUMBER_BITS<54>::count; // define a bit field large enough to hold "54"
* };
* \endcode
*/
template<UINT32 num> struct /*<UTILITY>*/ NUMBER_BITS
{
static const UINT32 count =
((num ? 1 : 0) +
((num>>1) ? 1 : 0) +
((num>>2) ? 1 : 0) +
((num>>3) ? 1 : 0) +
((num>>4) ? 1 : 0) +
((num>>5) ? 1 : 0) +
((num>>6) ? 1 : 0) +
((num>>7) ? 1 : 0) +
((num>>8) ? 1 : 0) +
((num>>9) ? 1 : 0) +
((num>>10) ? 1 : 0) +
((num>>11) ? 1 : 0) +
((num>>12) ? 1 : 0) +
((num>>13) ? 1 : 0) +
((num>>14) ? 1 : 0) +
((num>>15) ? 1 : 0) +
((num>>16) ? 1 : 0) +
((num>>17) ? 1 : 0) +
((num>>18) ? 1 : 0) +
((num>>19) ? 1 : 0) +
((num>>20) ? 1 : 0) +
((num>>21) ? 1 : 0) +
((num>>22) ? 1 : 0) +
((num>>23) ? 1 : 0) +
((num>>24) ? 1 : 0) +
((num>>25) ? 1 : 0) +
((num>>26) ? 1 : 0) +
((num>>27) ? 1 : 0) +
((num>>28) ? 1 : 0) +
((num>>29) ? 1 : 0) +
((num>>30) ? 1 : 0) +
((num>>31) ? 1 : 0));
};
} // namespace
#endif // file guard