user3445165
Reputation: 45
How does CPU differentiate REP and REPE instructions?
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?
Upvotes: 1
Views: 361
Answers (1)
Pascal Cuoq
Reputation: 80345
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.
Upvotes: 5
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