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SubjectRe: NOP instruction
On Tue, 15 Dec 1998, Chipzz wrote:

> I've always wondered... A much used NOP "instruction" is
> OR AX,AX (or similar);

Intel's NOP is actually XCHG AX,AX / XCHG EAX,EAX and it doesn't change
any flags. OR AX,AX would alter them.

> But doesn't this, as well as MOV DI,DI, set the zero flag???

MOV DI,DI also doesn't change flags.

--
__("< Marcin Kowalczyk * qrczak@knm.org.pl http://kki.net.pl/qrczak/
\__/ GCS/M d- s+:-- a21 C+++>+++$ UL++>++++$ P+++ L++>++++$ E->++
^^ W++ N+++ o? K? w(---) O? M- V? PS-- PE++ Y? PGP->+ t
QRCZAK 5? X- R tv-- b+>++ DI D- G+ e>++++ h! r--%>++ y-

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