bit_width

auto eve::bit_width = functor<bit_width_t>

inlineconstexpr

Defined in Header

#include <eve/module/core.hpp>

Callable Signatures

namespace eve
{
   // Regular overload
   constexpr auto bit_width(unsigned_value auto x) noexcept;                          // 1
 
   // Lanes masking
   constexpr auto bit_width[conditional_expr auto c](unsigned_value auto x) noexcept; // 2
   constexpr auto bit_width[logical_value auto m](unsigned_value auto x)    noexcept; // 2
}

Parameters

• x: unsigned argument.
• c: Conditional expression masking the operation.
• m: Logical value masking the operation.

Return value

1. The value of number of bits needed to store the value x, i.e. \(1+\lfloor\log2(x)\rfloor\) is returned.
2. The operation is performed conditionnaly.

Example

// revision 0
#include <eve/module/core.hpp>
#include <iostream>
 
int main()
{
  eve::wide wu0{0u, 1u, 2u, 3u, 4u, 5u, 6u, 7u};
 
  std::cout << "<- wu0                            = " << wu0 << "\n";
 
  std::cout << "-> bit_width(wu0)                 = " << eve::bit_width(wu0) << "\n";
  std::cout << "-> bit_width[ignore_last(2)](wu0) = " << eve::bit_width[eve::ignore_last(2)](wu0) << "\n";
  std::cout << "-> bit_width[wu0 != 0](wu0)       = " << eve::bit_width[wu0 != 0](wu0) << "\n";
}