src/libbiguint/bu_slbc.c


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/* ISC license. */

#include <skalibs/uint32.h>
#include <skalibs/biguint.h>

int bu_slbc (register uint32 *a, register unsigned int n, register int carry)
{
  register unsigned int i = 0 ;
  carry = !!carry ;
  for (; i < n ; i++)
  {
    register int c = a[i] >> 31 ;
    a[i] = (a[i] << 1) | carry ;
    carry = c ;
  }
  return carry ;
}