问题
I have read this answer, but I need to know what is the longest instruction length on Intel 386(which is 32-bit not 64 bit) without using any instruction prefixes.
Based on the manual, it is probably 12:
- Opcode: 2 bytes
- MOD/Rm: 1 byte
- SIB: 1 byte
- Displacement: 4 bytes
- Immediate: 4 bytes
- Total: 12
Is this the correct answer?
回答1:
On 80386 that would be 11 bytes:
- Opcode: 1 byte
- MOD/RM: 1 byte
- SIB: 1 byte
- Displacement: 4 bytes
- Immediate: 4 bytes
The 2-byte opcodes are using the 0Fh instruction prefix which obviously is a prefix.
来源：https://stackoverflow.com/questions/34052200/what-is-the-maximum-length-an-intel-386-instruction-without-any-prefixes