From: Bakul Shah <bakul@iitbombay.org>
To: Norman Wilson <norman@oclsc.org>
Cc: tuhs@tuhs.org
Subject: Re: [TUHS] Memory management in Dennis Ritchie's C Compiler
Date: Mon, 17 Aug 2020 15:55:31 -0700 [thread overview]
Message-ID: <7B3D5DB4-B593-4EC8-ABEE-2AC77DFE3F73@iitbombay.org> (raw)
In-Reply-To: <20200817223229.5401A4422E@lignose.oclsc.org>
On Aug 17, 2020, at 3:32 PM, Norman Wilson <norman@oclsc.org> wrote:
>
> The hardest but most-interesting part was optimizing.
> lcc does a lot of optimization work by itself, and
> initially I'd hoped to dispense with a separate c2
> pass entirely, but that turns out not to be feasible
> on machines like the VAX or the PDP-11: internally
> lcc separates something like
> c = *p++;
> into two operations
> c = *p;
> p++;
> and makes two distinct calls to the code generator.
> To sew them back together from
> cvtbl (p),c
> incl p
> to
> cvtbl (p)+,c
> requires external help; lcc just can't see that
> what it thinks of as two distinct expressions
> can be combined.
Didn't lcc use iburg or some such to generate the
code generator, which could do such things?
> See the lcc book for details. Read the book anyway;
> it's the one case I know of in which the authors
> followed strict Literate Programming rules and made
> a big success of it. Not only is the compiler well-
> documented, but the result is a wonderful tour
> through the construction and design decisions of a
> large program that does real work.
Agree. They used noweb. Probably with a troff backend?
next prev parent reply other threads:[~2020-08-17 22:56 UTC|newest]
Thread overview: 46+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-08-17 22:32 Norman Wilson
2020-08-17 22:55 ` Bakul Shah [this message]
2020-08-17 23:12 ` Chet Ramey
2020-08-18 6:33 ` arnold
-- strict thread matches above, loose matches on Subject: below --
2020-08-27 8:37 Paul Ruizendaal
2020-08-26 15:59 Noel Chiappa
2020-08-26 16:09 ` Warner Losh
2020-08-26 19:13 ` Clem Cole
2020-08-26 16:14 ` Jim Geist
2020-08-26 17:31 ` John Cowan
2020-08-26 13:24 Doug McIlroy
2020-08-26 15:41 ` John Cowan
2020-08-25 9:36 Steve Simon
2020-08-17 19:51 Noel Chiappa
2020-08-17 19:27 Noel Chiappa
2020-08-17 19:30 ` Larry McVoy
2020-08-17 19:44 ` Dan Halbert
2020-08-17 19:50 ` Paul Winalski
2020-08-17 22:05 ` Arthur Krewat
2020-08-18 0:52 ` Rob Gingell
2020-08-17 2:02 Noel Chiappa
2020-08-17 18:02 ` Paul Winalski
2020-08-17 18:13 ` Jim Geist
2020-08-17 18:48 ` Paul Winalski
2020-08-17 19:08 ` Jim Geist
2020-08-17 19:28 ` Paul Winalski
2020-08-17 19:35 ` Jim Geist
2020-08-17 19:41 ` Richard Salz
2020-08-17 23:40 ` Steffen Nurpmeso
2020-08-15 21:50 Dibyendu Majumdar
2020-08-16 15:20 ` arnold
2020-08-16 15:27 ` Jim Geist
2020-08-17 16:13 ` Dan Cross
2020-08-17 20:16 ` Dibyendu Majumdar
2020-08-17 20:34 ` Paul Winalski
2020-08-17 20:43 ` Dibyendu Majumdar
2020-08-17 21:05 ` Warner Losh
2020-08-17 22:47 ` Dave Horsfall
2020-08-17 23:06 ` Nemo Nusquam
2020-08-17 21:29 ` Dibyendu Majumdar
2020-08-24 15:58 ` Dan Cross
2020-08-24 17:08 ` John Cowan
2020-08-24 17:15 ` Clem Cole
2020-08-24 17:24 ` Clem Cole
2020-08-24 17:20 ` Dan Cross
2020-08-25 23:06 ` Arthur Krewat
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=7B3D5DB4-B593-4EC8-ABEE-2AC77DFE3F73@iitbombay.org \
--to=bakul@iitbombay.org \
--cc=norman@oclsc.org \
--cc=tuhs@tuhs.org \
/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).