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From: csuwr@warwick.ac.uk (Derek Hunter)
Newsgroups: comp.sys.acorn
Subject: Re: Saving the old pc in APCS
Message-ID: <V'X&9{^@warwick.ac.uk>
Date: 4 Apr 91 13:48:13 GMT
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In article <6080@acorn.co.uk> john@acorn.co.uk (John Bowler) writes:
>
>                                                    Ok, we admit
>it, you have to use that instruction sequence :-)

Just as well I decided to follow APCS then. (Can I quote you on the
 mandatory nature of the code fraction? ;-)

Incidentally, a fair while ago, you mentioned that debugging compilers is
 easier if one follows APCS. While at the moment, I can inspect the code
 `by hand' [snigger] and since it's totally unoptimised, it's very readable,
 I imagine pointers will start going awry later when the computer decides
 to get clever with the code. !! Scrounge alert !! Can I get my hands on some
 of Acorn's compiler development programs, or (and perhaps, more
 importantly), some blurfl about the interface for the (latest! :-)
 Shared C Lib, like, man, for little or no bread?

>                                       . . .  the callee can check to
>see if there is enough room on the stack.  If there isn't . . .

Urk! At the moment, my code's code does nothing to check about the stack
 size, or anything. Can I just rely on the system stack for the moment
 (especially if it's running as a module), or will I have to set something
 up at the start of the code? (I doubt it will be running as RISCware
 just yet...)

How about having my stack floating off somewhere towards the top of
 application space (Just under the 4 megabyte boundary) and mapping pages
 into (out of) place as I need them (although I suppose that a 8/16/32K page
 multiple is a bit much for a single program's stack), or must I limit myself
 to tucking the stack into heap space, in which case, how does one determine
 an appropriate amount to grab for heap space at the start?

I was rather hoping to avoid set-up, run-time and exit code, but it looks
 like things are rather more complicated than I had hoped (naive old me).

  .-------------------------------------------------------------------.
  | `It looks like a recursive descent parser that's been trodden on' |
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                        | csuwr@cu.warwick.ac.uk |
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