Function get_codelet_prio

libavutil/tx.c:367–398

};

static int get_codelet_prio(const FFTXCodelet *cd, int cpu_flags, int len)
{
    int prio = cd->prio;
    int max_factor = 0;

    /* If the CPU has a SLOW flag, and the instruction is also flagged
     * as being slow for such, reduce its priority */
    for (int i = 0; i < FF_ARRAY_ELEMS(cpu_slow_penalties); i++) {
        if ((cpu_flags & cd->cpu_flags) & cpu_slow_penalties[i][0])
            prio -= cpu_slow_penalties[i][1];
    }

    /* Prioritize aligned-only codelets */
    if ((cd->flags & FF_TX_ALIGNED) && !(cd->flags & AV_TX_UNALIGNED))
        prio += 64;

    /* Codelets for specific lengths are generally faster */
    if ((len == cd->min_len) && (len == cd->max_len))
        prio += 64;

    /* Forward-only or inverse-only transforms are generally better */
    if ((cd->flags & (FF_TX_FORWARD_ONLY | FF_TX_INVERSE_ONLY)))
        prio += 64;

    /* Larger factors are generally better */
    for (int i = 0; i < TX_MAX_SUB; i++)
        max_factor = FFMAX(cd->factors[i], max_factor);
    if (max_factor)
        prio += 16*max_factor;

    return prio;
}

typedef struct FFTXLenDecomp {
    int len;