From:	"Andrew Crabtree" <andrewc AT rosemail DOT rose DOT hp DOT com>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: assembly language subroutines
Date:	Wed, 19 Aug 1998 13:25:25 -0700
Organization:	Hewlett-Packard, Roseville
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References:	<E0z9ELK-0001GK-00 AT sable DOT ox DOT ac DOT uk>
NNTP-Posting-Host:	ros51675cra.rose.hp.com
To:	djgpp AT delorie DOT com
DJ-Gateway:	from newsgroup comp.os.msdos.djgpp

>I think `leave' is a single byte opcode
yep
> so it's more efficient memory-wise to use it
yep

> I'm not sure about the timings, perhaps it's
>faster to execute too.

not really.  Its 3 clocks and doesn't pair well on a pentium.

>I don't have any documentation saying explicitly what `enter' and
>`leave' do to registers, only how they work as a pair.
correct.  They don't change flags at all and only affect esp/ebp

>I also assume (working backwards from that assumption) that "enter X"

enter is a little more complicated then that as you also specify a nesting
level.  It is very slow ... >10 clocks on a pentium

Andy

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