Newsgroups: comp.arch
Path: utzoo!henry
From: henry@utzoo.uucp (Henry Spencer)
Subject: Re: Self-modifying code
Message-ID: <1988Jul18.231158.19500@utzoo.uucp>
Organization: U of Toronto Zoology
References: <5254@june.cs.washington.edu> <76700032@p.cs.uiuc.edu> <1090@ficc.UUCP>
Date: Mon, 18 Jul 88 23:11:58 GMT

In article <1090@ficc.UUCP> peter@ficc.UUCP (Peter da Silva) writes:
>You can save an even greater factor by building the BitBlt into the
>hardware....

No.  You can save a large factor over *poor* software implementations of
BitBlt.  Not over good ones.  The dynamic-compilation implementations on
the Blit et al run the memory at nearly full speed for the usual cases
of BitBlt; it is fundamentally impossible to do better.  Commodore et al
find hardware implementations attractive because they don't know how to
write good software.
-- 
Anyone who buys Wisconsin cheese is|  Henry Spencer at U of Toronto Zoology
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