4 ms·
They're one byte opcodes, but not one byte ops. Most of them have operands which are encoded in a ModRM byte which follows the opcode. The ModRM may be followed
by sparkie 1y ago
They're one byte opcodes, but not one byte ops. Most of them have operands which are encoded in a ModRM byte which follows the opcode. The ModRM may be followed by a SIB byte, and that may be followed by a a variable size immediate|displacement. There are also optional prefixes to the opcode.