ir_bk_prefetch, /**< GCC __builtin_prefetch() */
ir_bk_ffs, /**< GCC __builtin_ffs(): find first (least) significant 1 bit */
ir_bk_clz, /**< GCC __builtin_clz(): count leading zero */
ir_bk_prefetch, /**< GCC __builtin_prefetch() */
ir_bk_ffs, /**< GCC __builtin_ffs(): find first (least) significant 1 bit */
ir_bk_clz, /**< GCC __builtin_clz(): count leading zero */