anchor.diff:                  ibclr(-1_bit_kind,n)+1_bit_kind ) ))
             else
               nperm = nperm + popcnt(iand(det1(k,ispin),               &
  -                ibset(0_bit_kind,m-1)-1_bit_kind)) +                 &
  -                popcnt(iand(det1(j,ispin), ibclr(-1_bit_kind,n) +1_bit_kind))
  +                ibset(0_bit_kind,m-1)-1_bit_kind)) 
  +            if (n < bit_kind_size) then
  +               nperm = nperm + popcnt(iand(det1(j,ispin), ibclr(-1_bit_kind,n) +1_bit_kind))
  +            endif
               do l=j+1,k-1
                 nperm = nperm + popcnt(det1(l,ispin))
               end do
  
positive.code:               ibclr(-1_bit_kind,n)+1_bit_kind ) ))
          else
            nperm = nperm + popcnt(iand(det1(k,ispin),                 &
                ibset(0_bit_kind,m-1)-1_bit_kind)) +                   &
                popcnt(iand(det1(j,ispin), ibclr(-1_bit_kind,n) +1_bit_kind))
            do i=j+1,k-1
              nperm = nperm + popcnt(det1(i,ispin))
            end do
  
negative.code:         nperm = popcnt(iand(det1(j,ispin),                           &
              iand(ibset(0_bit_kind,m-1)-1_bit_kind,ibclr(-1_bit_kind,n)+1_bit_kind)))
        else
          nperm = nperm + popcnt(iand(det1(k,ispin),ibset(0_bit_kind,m-1)-1_bit_kind))
          if (n < bit_kind_size) then
              nperm = nperm + popcnt(iand(det1(j,ispin),ibclr(-1_bit_kind,n)+1_bit_kind))
          endif
          do i=j+1,k-1
            nperm = nperm + popcnt(det1(i,ispin))
          end do
  