Date: Thu, 9 Nov 1995 15:59:35 -0500 (EST) From: Chuck Robey <chuckr@glue.umd.edu> To: Michael Smith <msmith@atrad.adelaide.edu.au> Cc: hackers@FreeBSD.org Subject: Re: Load/Store using FPU regs ... Message-ID: <Pine.SUN.3.91.951109155845.10929A-100000@latte.eng.umd.edu> In-Reply-To: <199511090901.JAA09519@genesis.atrad.adelaide.edu.au>
next in thread | previous in thread | raw e-mail | index | archive | help
On Thu, 9 Nov 1995, Michael Smith wrote:
> koshy@blr.novell.com stands accused of saying:
> > >>> L20: fldl (%ebx) fstpl (%ecx) ...
> > >>>
> > >>> The resulting program copies data at about 60 Megabytes per
> > >>> second.
> >
> >
> > Using the FPU registers for memmove/bitblt operations was a technique
> > I first saw on an i860. We used to do a series of reads into FPU regs
>
> Wheras those of us with 68K backgrounds are rolling in the aisles about
> this one 8)
>
> (For the uninitiated; the 68K can read/write arbitrary groups of registers
> and increment/decrement the source/destination pointers at the same time.
> Depending on coding technique, you can read or write as much as 56
> bytes at a time; the big win (microcoded processor, remember) being no
> instruction fetches between reads. It's a pity that Motorola have axed
> it as a mainstram family 8( )
Axed the family? They have the newest child out now, 68060, I don't
think they've axed the family.
>
> Anyway, enough from the nostalgia corner - I'm too young for this!
>
> --
> ]] Mike Smith, Software Engineer msmith@atrad.adelaide.edu.au [[
> ]] Genesis Software genesis@atrad.adelaide.edu.au [[
> ]] High-speed data acquisition and (GSM mobile) 041-122-496 [[
> ]] realtime instrument control (ph/fax) +61-8-267-3039 [[
> ]] My car has "demand start" -Terry Lambert UNIX: live FreeBSD or die! [[
>
==========================================================================
Chuck Robey chuckr@eng.umd.edu, I run FreeBSD-current on n3lxx + Journey2
Here's OJ's internet address in hex code:
00 2F 2F 2F 2F 5C 7F 2D 0D 15 1B 19 24 24 24 18
If you can't recall the translation, here it is:
null character, slash, slash, slash, slash, backslash, rubout, dash,
carriage return, negative acknowledgement, escape, end of media,
dollar sign, dollar sign, dollar sign, cancel
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?Pine.SUN.3.91.951109155845.10929A-100000>