内存布局与对齐

// in hex
// +-------------+-------------+-------------+-------------+-------------+-------------+-------------+-------------+
// |      7 H    |      6      |      5      |      4      |      3      |      2      |      1      |      0 L    |
// +-------------+-------------+-------------+-------------+-------------+-------------+-------------+-------------+
// | Rer-R Rebnd | Rer-R Cmprs | Rer-L Rebnd | Rer-L Cmprs | Frn-R Rebnd | Frn-R Cmprs | Frn-L Rebnd | Frn-L Cmprs |
// +-------------+-------------+-------------+-------------+-------------+-------------+-------------+-------------+
struct gain_set_s {
    uint8_t rear_right_rebound;
    uint8_t rear_right_compress;
    uint8_t rear_left_rebound;
    uint8_t rear_left_compress;
    uint8_t front_right_rebound;
    uint8_t front_right_compress; 
    uint8_t front_left_rebound;
    uint8_t front_left_compress;
};
typedef struct gain_set_s gain_set_t;
gain_set_t set = {
    .rear_right_rebound = 0xe0,
    .rear_right_compress = 0xd0,
    .rear_left_rebound = 0xc0,
    .rear_left_compress = 0xb0,
    .front_right_rebound = 0xa0,
    .front_right_compress = 0x90,
    .front_left_rebound = 0x80,
    .front_left_compress = 0x70,
};
uint64_t tmp = *(uint64_t*)&set;
info("temp set is : %lx", tmp); // 转换为uint64后，hex为：0x708090a0b0c0d0e0;

log_arrary_desc((uint8_t*)&set, 8, LOG_ARR_BYTE1, "temp set is :");
// src/main.c:157 main: temp set is ::e0 d0 c0 b0 a0 90 80 70
// 上面是按照uint8 进行内存打印的内存布局
// 目前可得结论为：单字节结构体，转换同等数值hex是反着来的，内存布局是正着的