From owner-freebsd-hackers  Mon Aug 27  3:18:33 2001
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Date: Mon, 27 Aug 2001 13:18:14 +0300
From: Valentin Nechayev <netch@lucky.net>
To: Steve Roome <stephen_roome@yahoo.com>
Cc: freebsd-hackers@FreeBSD.ORG
Subject: Re: function calls/rets in assembly
Message-ID: <20010827131814.A18891@lucky.net>
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References: <20010824010139.E365@dylan.home> <20010827081112.C365@dylan.home>
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 Mon, Aug 27, 2001 at 08:11:12, stephen_roome wrote about "Re: function calls/rets in assembly": 

> One final question... (which may be a gcc question, sorry if it is..)
> 
> why do we have some people proposing the use of "leave". When from the
> docs I've read, leave takes longer than a mov and return ?

To optimize for some higher than i386, use -mcpu=<version>
With -mcpu=i486 and higher, gcc writes

        movl %ebp,%esp
        popl %ebp

Also consider -march= option.


/netch

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