pub const PREFIX_REPZ: u8 = 0b01000;
pub const PREFIX_REPNZ: u8 = 0b10000;
pub const PREFIX_MASK_REP: u8 = PREFIX_REPZ | PREFIX_REPNZ;

pub const PREFIX_MASK_OPSIZE: u8 = 0b100000;
pub const PREFIX_MASK_ADDRSIZE: u8 = 0b1000000;

pub const PREFIX_66: u8 = PREFIX_MASK_OPSIZE;
pub const PREFIX_67: u8 = PREFIX_MASK_ADDRSIZE;
pub const PREFIX_F2: u8 = PREFIX_REPNZ;
pub const PREFIX_F3: u8 = PREFIX_REPZ;

pub const SEG_PREFIX_ZERO: u8 = 7;

pub const PREFIX_MASK_SEGMENT: u8 = 0b111;