From: rob@plan9.research.att.com rob@plan9.research.att.com
Subject: Why compile.c ?
Date: Tue, 19 Apr 1994 13:17:36 -0400 [thread overview]
Message-ID: <19940419171736.0DRYq0DJCEWPSwRW8WyEdCek8pMv5dObVWA3yLNd0kk@z> (raw)
Why? Why do by hand what a machine can do just
as well or better?
The SPARC MMU is inexcusably badly designed.
To make a single kernel that supports all variants
one must either write oodles of ugly assembly code,
with loops that must be unrolled for speed, or generate
code at boot-time tailored to the machine at hand.
We chose the latter approach because it's really
less code to maintain. I wrote the compiler in just
a couple of hours one afternoon. It's very easy stuff.
Since some of the code must be generated - for
example, cache line sizes vary from model to model -
what the hell? Why not generate it all? Easy, and
susceptible to adaptation as SUN's creative minds
continue to design hardware.
next reply other threads:[~1994-04-19 17:17 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
1994-04-19 17:17 rob [this message]
-- strict thread matches above, loose matches on Subject: below --
1994-04-19 16:22 yodaiken
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=19940419171736.0DRYq0DJCEWPSwRW8WyEdCek8pMv5dObVWA3yLNd0kk@z \
--to=rob@plan9.research.att.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).