NaiveUtils.hpp

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#include <cstdint>
 
#ifndef TPGLIBS_NAIVEUTILS_HPP_
#define TPGLIBS_NAIVEUTILS_HPP_
 
namespace tpglibs {
 
// Modeled to be consistent with AVX.
inline int16_t
_naive_div_int16(const int16_t& a, const int16_t& b)
{
  int16_t vb = (1 << 15) / b;  //  1 / b * 2^15
  int32_t mulhrs = a * vb;     //  a / b * 2^15
  mulhrs = (mulhrs >> 14) + 1; // (a / b * 2^15) * 2^-14 + 1 ~ a / b * 2 + 1
  mulhrs = mulhrs >> 1;        //~ a / b. The +1 causes unorthodox rounding.
  return (int16_t)(mulhrs);
}
 
} // namespace tpglibs
 
#endif // TPGLIBS_NAIVEUTILS_HPP_