Path: utzoo!utgpu!news-server.csri.toronto.edu!rutgers!cs.utexas.edu!swrinde!zaphod.mps.ohio-state.edu!van-bc!rsoft!mindlink!a684
From: a684@mindlink.UUCP (Nick Janow)
Newsgroups: comp.lang.forth
Subject: Re: Floating point stack
Message-ID: <2978@mindlink.UUCP>
Date: 28 Aug 90 18:04:32 GMT
Organization: MIND LINK! - British Columbia, Canada
Lines: 40


koopman@a.gp.cs.cmu.edu (Philip Koopman) writes:

> As Mitch has pointed out, in a great many cases code can be written to be
> insensitive to the stack model.  In those cases where such code is extremely
> inefficient, portable code could use conditional compilation to provide two
> versions.  My guess is that such code is very limited in size when viewed in
> the context of an entire application (and, if speed is that important, it's
> probably in assembler anyway).

Your argument could also apply to using a separate stack only--and offering an
optional stack-machine coded version for the speed-critical sections.  :-)

> I do not know whether a separate or unified stack is "best".  One of my
> criteria will be which one a C compiler can use best for stack machines (but,
> the jury is still out).  I requested that the standard not preclude use of a
> unified stack.

While I respect Harris and appreciate the support they are giving FORTH, I
don't think that the ANS standard should be set just to suit C compilers
running on an RTX2000.  You've just admitted that code for a separate FP stack
might be more viable in the marketplace.  Part of the reasons for the present
method was to accommodate Harris--and you don't even know if that's what you
want?  Maybe you Harris engineers could brainstorm a bit on the issue...before
the ANS FORTH is engraved in stone.

The present FP method (separate and combined stacks) was decided upon after
lengthy discussion.  However, there were 15 or fewer people present (some of
whom were less than experts on the issue) and there were not that many good
arguments put forward in the proposals, so it was not a massive consensus of
the entire FORTH community.  Despite the consensus (I think it was 14 in
favour, 1 {me} abstaining), I felt that the mood was "This is the best
compromise we can come up with at this time.  Let's see what the reaction is."

To anyone interested in the FP issue: if you've got a new slant on the issue or
a convincing argument for a particular method, SEND IT IN!  Post comments,
ideas, etc here too; maybe something better can come out of the discussion.  If
you're not happy with the present compromise, offer something constructive in
order to change it.  If you can't offer a better solution, admit it and stop
complaining.