R4
#define R4(x) (((x) >> 4) & 0xf)
#define R4 4
#define R4 77
#define R4 4
#define R4 4
#define R4 4
#define R4 4
#define R4 BPF_REG_4
#define R4 0x20
#define R4 4 * 8