int fp_sqr(fp_int *A, fp_int *B)
{
    int err;
    int y, oldused;

    oldused = B->used;
    y = A->used;

    /* call generic if we're out of range */
    if (y + y > FP_SIZE) {
       err = fp_sqr_comba(A, B);
       goto clean;
    }

#if defined(TFM_SQR3) && FP_SIZE >= 6
        if (y <= 3) {
           err = fp_sqr_comba3(A,B);
           goto clean;
        }
#endif
#if defined(TFM_SQR4) && FP_SIZE >= 8
        if (y == 4) {
           err = fp_sqr_comba4(A,B);
           goto clean;
        }
#endif
#if defined(TFM_SQR6) && FP_SIZE >= 12
        if (y <= 6) {
           err = fp_sqr_comba6(A,B);
           goto clean;
        }
#endif
#if defined(TFM_SQR7) && FP_SIZE >= 14
        if (y == 7) {
           err = fp_sqr_comba7(A,B);
           goto clean;
        }
#endif
#if defined(TFM_SQR8) && FP_SIZE >= 16
        if (y == 8) {
           err = fp_sqr_comba8(A,B);
           goto clean;
        }
#endif
#if defined(TFM_SQR9) && FP_SIZE >= 18
        if (y == 9) {
           err = fp_sqr_comba9(A,B);
           goto clean;
        }
#endif
#if defined(TFM_SQR12) && FP_SIZE >= 24
        if (y <= 12) {
           err = fp_sqr_comba12(A,B);
           goto clean;
        }
#endif
#if defined(TFM_SQR17) && FP_SIZE >= 34
        if (y <= 17) {
           err = fp_sqr_comba17(A,B);
           goto clean;
        }
#endif
#if defined(TFM_SMALL_SET)
        if (y <= 16) {
           err = fp_sqr_comba_small(A,B);
           goto clean;
        }
#endif
#if defined(TFM_SQR20) && FP_SIZE >= 40
        if (y <= 20) {
           err = fp_sqr_comba20(A,B);
           goto clean;
        }
#endif
#if defined(TFM_SQR24) && FP_SIZE >= 48
        if (y <= 24) {
           err = fp_sqr_comba24(A,B);
           goto clean;
        }
#endif
#if defined(TFM_SQR28) && FP_SIZE >= 56
        if (y <= 28) {
           err = fp_sqr_comba28(A,B);
           goto clean;
        }
#endif
#if defined(TFM_SQR32) && FP_SIZE >= 64
        if (y <= 32) {
           err = fp_sqr_comba32(A,B);
           goto clean;
        }
#endif
#if defined(TFM_SQR48) && FP_SIZE >= 96
        if (y <= 48) {
           err = fp_sqr_comba48(A,B);
           goto clean;
        }
#endif
#if defined(TFM_SQR64) && FP_SIZE >= 128
        if (y <= 64) {
           err = fp_sqr_comba64(A,B);
           goto clean;
        }
#endif
       err = fp_sqr_comba(A, B);

clean:
  /* zero any excess digits on the destination that we didn't write to */
  for (y = B->used; y >= 0 && y < oldused; y++) {
    B->dp[y] = 0;
  }

  return err;
}
int fp_sqr(fp_int *A, fp_int *B)
{
    int err;
    int y, oldused;

    oldused = B->used;
    y = A->used;

     
    if (y + y > FP_SIZE) {
       err = fp_sqr_comba(A, B);
       goto clean;
    }

#if defined(TFM_SQR3) && FP_SIZE >= 6
        if (y <= 3) {
           err = fp_sqr_comba3(A,B);
           goto clean;
        }
#endif
#if defined(TFM_SQR4) && FP_SIZE >= 8
        if (y == 4) {
           err = fp_sqr_comba4(A,B);
           goto clean;
        }
#endif
#if defined(TFM_SQR6) && FP_SIZE >= 12
        if (y <= 6) {
           err = fp_sqr_comba6(A,B);
           goto clean;
        }
#endif
#if defined(TFM_SQR7) && FP_SIZE >= 14
        if (y == 7) {
           err = fp_sqr_comba7(A,B);
           goto clean;
        }
#endif
#if defined(TFM_SQR8) && FP_SIZE >= 16
        if (y == 8) {
           err = fp_sqr_comba8(A,B);
           goto clean;
        }
#endif
#if defined(TFM_SQR9) && FP_SIZE >= 18
        if (y == 9) {
           err = fp_sqr_comba9(A,B);
           goto clean;
        }
#endif
#if defined(TFM_SQR12) && FP_SIZE >= 24
        if (y <= 12) {
           err = fp_sqr_comba12(A,B);
           goto clean;
        }
#endif
#if defined(TFM_SQR17) && FP_SIZE >= 34
        if (y <= 17) {
           err = fp_sqr_comba17(A,B);
           goto clean;
        }
#endif
#if defined(TFM_SMALL_SET)
        if (y <= 16) {
           err = fp_sqr_comba_small(A,B);
           goto clean;
        }
#endif
#if defined(TFM_SQR20) && FP_SIZE >= 40
        if (y <= 20) {
           err = fp_sqr_comba20(A,B);
           goto clean;
        }
#endif
#if defined(TFM_SQR24) && FP_SIZE >= 48
        if (y <= 24) {
           err = fp_sqr_comba24(A,B);
           goto clean;
        }
#endif
#if defined(TFM_SQR28) && FP_SIZE >= 56
        if (y <= 28) {
           err = fp_sqr_comba28(A,B);
           goto clean;
        }
#endif
#if defined(TFM_SQR32) && FP_SIZE >= 64
        if (y <= 32) {
           err = fp_sqr_comba32(A,B);
           goto clean;
        }
#endif
#if defined(TFM_SQR48) && FP_SIZE >= 96
        if (y <= 48) {
           err = fp_sqr_comba48(A,B);
           goto clean;
        }
#endif
#if defined(TFM_SQR64) && FP_SIZE >= 128
        if (y <= 64) {
           err = fp_sqr_comba64(A,B);
           goto clean;
        }
#endif
       err = fp_sqr_comba(A, B);

clean:
   
  for (y = B->used; y >= 0 && y < oldused; y++) {
    B->dp[y] = 0;
  }

  return err;
}