◆ shift_left()

Value boost::simd::shift_left ( Value const &  x,
IntegerValue const &  n 
)

This function object returns the first parameter shifted left by the second one.

Infix notation can be used with operator '<<'

Header <boost/simd/function/shift_left.hpp>
Precondition
the second parameter must be of integer type scalar or associated to the first parameter
Note:
  • on many architectures a scalar second parameter results in a much faster call
alias shl
See also
shift_right, shr, rshl, rshr, rol, ror
Example:
#include <boost/simd/bitwise.hpp>
#include <boost/simd/pack.hpp>
#include <iostream>
namespace bs = boost::simd;
using iT = std::int32_t;
using pack_it = bs::pack<iT, 4>;
int main() {
pack_it pi = {1, 2, -1, 3};
pack_it qi = {1, 2, 4, 3};
std::cout << "---- simd" << '\n'
<< "<- pi = " << pi << '\n'
<< "<- qi = " << qi << '\n'
<< "-> bs::shift_left(pi, qi) = " << bs::shift_left(pi, qi) << '\n';
iT xi = 2, yi = 3;
std::cout << "---- scalar" << '\n'
<< "<- xi = " << xi << '\n'
<< "<- yi = " << yi << '\n'
<< "-> bs::shift_left(xi, yi) = " << bs::shift_left(xi, yi) << '\n';
return 0;
}
Possible output:
---- simd
<- pi = (1, 2, -1, 3)
<- qi = (1, 2, 4, 3)
-> bs::shift_left(pi, qi) = (2, 8, -16, 24)
---- scalar
<- xi = 2
<- yi = 3
-> bs::shift_left(xi, yi) = 16