How does CPU differentiate REP and REPE instructions?
Question
According to this manual, REP and REPE instructions have different behaviour, but the same opcode F3 .
How does CPU differentiate this two commands, if they both have the same opcode?
1 answers
solution1
5 ACCPTED 2015-06-24 13:14:50
REP and REPE are prefixes , not instructions. Some instructions accept the REPE prefix. Others accept REP . The ISA was designed so that no instruction accepts both, so the problem does not arise.
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