Re: Confused by Intel's Opcode docs

[jongware] schrieb:
"Always" is the default, but can be overriden to 'the other' by prefixing
66h (Segment Override Prefix).
The same goes for word/dword register and mem operands (mov ax,1 vs. mov
eax,1). The prefix variants are *always* slower than the non-prefix.

Thanks, that was the missing info, I guess. Though of course with AT&T
syntax, one manually indicates the prefix (movl and stuff). Still, that
using another than the native type would be slower is only to be
expected.

Thanks for all the great info!

Cheers,
-- M. Uli Kusterer
http://www.zathras.de

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Relevant Pages

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