static CCPrepare gen_prepare_eflags_c(DisasContext *s, TCGv reg)
{
    TCGv t0, t1;
    int size, shift;

    switch (s->cc_op) {
    case CC_OP_SUBB ... CC_OP_SUBQ:
        /* (DATA_TYPE)CC_SRCT < (DATA_TYPE)CC_SRC */
        size = s->cc_op - CC_OP_SUBB;
        t1 = gen_ext_tl(cpu_tmp0, cpu_cc_src, size, false);
        /* If no temporary was used, be careful not to alias t1 and t0.  */
        t0 = TCGV_EQUAL(t1, cpu_cc_src) ? cpu_tmp0 : reg;
        tcg_gen_mov_tl(t0, cpu_cc_srcT);
        gen_extu(size, t0);
        goto add_sub;

    case CC_OP_ADDB ... CC_OP_ADDQ:
        /* (DATA_TYPE)CC_DST < (DATA_TYPE)CC_SRC */
        size = s->cc_op - CC_OP_ADDB;
        t1 = gen_ext_tl(cpu_tmp0, cpu_cc_src, size, false);
        t0 = gen_ext_tl(reg, cpu_cc_dst, size, false);
    add_sub:
        return (CCPrepare) { .cond = TCG_COND_LTU, .reg = t0,
                             .reg2 = t1, .mask = -1, .use_reg2 = true };

    case CC_OP_LOGICB ... CC_OP_LOGICQ:
    case CC_OP_CLR:
    case CC_OP_POPCNT:
        return (CCPrepare) { .cond = TCG_COND_NEVER, .mask = -1 };

    case CC_OP_INCB ... CC_OP_INCQ:
    case CC_OP_DECB ... CC_OP_DECQ:
        return (CCPrepare) { .cond = TCG_COND_NE, .reg = cpu_cc_src,
                             .mask = -1, .no_setcond = true };

    case CC_OP_SHLB ... CC_OP_SHLQ:
        /* (CC_SRC >> (DATA_BITS - 1)) & 1 */
        size = s->cc_op - CC_OP_SHLB;
        shift = (8 << size) - 1;
        return (CCPrepare) { .cond = TCG_COND_NE, .reg = cpu_cc_src,
                             .mask = (target_ulong)1 << shift };

    case CC_OP_MULB ... CC_OP_MULQ:
        return (CCPrepare) { .cond = TCG_COND_NE,
                             .reg = cpu_cc_src, .mask = -1 };

    case CC_OP_BMILGB ... CC_OP_BMILGQ:
        size = s->cc_op - CC_OP_BMILGB;
        t0 = gen_ext_tl(reg, cpu_cc_src, size, false);
        return (CCPrepare) { .cond = TCG_COND_EQ, .reg = t0, .mask = -1 };

    case CC_OP_ADCX:
    case CC_OP_ADCOX:
        return (CCPrepare) { .cond = TCG_COND_NE, .reg = cpu_cc_dst,
                             .mask = -1, .no_setcond = true };

    case CC_OP_EFLAGS:
    case CC_OP_SARB ... CC_OP_SARQ:
        /* CC_SRC & 1 */
        return (CCPrepare) { .cond = TCG_COND_NE,
                             .reg = cpu_cc_src, .mask = CC_C };

    default:
       /* The need to compute only C from CC_OP_DYNAMIC is important
          in efficiently implementing e.g. INC at the start of a TB.  */
       gen_update_cc_op(s);
       gen_helper_cc_compute_c(reg, cpu_cc_dst, cpu_cc_src,
                               cpu_cc_src2, cpu_cc_op);
       return (CCPrepare) { .cond = TCG_COND_NE, .reg = reg,
                            .mask = -1, .no_setcond = true };
    }
}

The product constructs all or part of a code segment using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the syntax or behavior of the intended code segment.