Sample arch, virtaxy, has kinda simple (but not effective) instruction format:
IP[0] = opcode
IP[1] = arg1
IP[2] = arg2
IP[3] = arg3
However, real archs have more complex formats. Some of them, like 8086, have different sizes for instructions, so user-defined decoder may be combined with fetch stage. Decoder should work in a simple and clear way without user having to go into the machine structure.
Sample arch, virtaxy, has kinda simple (but not effective) instruction format:
However, real archs have more complex formats. Some of them, like 8086, have different sizes for instructions, so user-defined decoder may be combined with fetch stage. Decoder should work in a simple and clear way without user having to go into the machine structure.