Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > comp.lang.forth > #52761

Re: Data Stack of Just Pointers?

Show all headers | View raw

trans <transfire@gmail.com> writes:
>Would a Forth implementation with a data stack that just contains reference=
> pointers have really bad performance? Is that just a stupid idea?

Given that it's a very common approach in many language
implementations (e.g., Lisp, or the object part of Java), and for good
reasons, it's not a stupid idea.  It has significant performance cost,
but despite that cost, the designers and implementors of these
languages have chosen this approach for the general case.  They then
try to reduce the cost in various common cases, with mixed success;
the cost is known as boxing and unboxing, and searching for these
terms should give you some literature on the performance effects of
this approach and how to reduce the cost.

> I was think=
>ing there could also be a kind of "cache stack" to pre-fetch the data that =
>the data stack points to.

I expect that the data on the stack is in the data cache of the CPU,
because it was accessed recently (otherwise, how does it get on the
stack); so I don't expect prefetching to help for these cases.  If you
mean something else, it's unclear what you mean.

- anton
-- 
M. Anton Ertl  http://www.complang.tuwien.ac.at/anton/home.html
comp.lang.forth FAQs: http://www.complang.tuwien.ac.at/forth/faq/toc.html
     New standard: http://www.forth200x.org/forth200x.html
   EuroForth 2016: http://www.euroforth.org/ef16/

Back to comp.lang.forth | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

Thread

Data Stack of Just Pointers? trans <transfire@gmail.com> - 2016-11-18 10:10 -0800
  Re: Data Stack of Just Pointers? Paul Rubin <no.email@nospam.invalid> - 2016-11-18 10:45 -0800
  Re: Data Stack of Just Pointers? Rod Pemberton <NeedNotReplyHere@xrsevnneqk.cem> - 2016-11-18 20:39 -0500
    Re: Data Stack of Just Pointers? minforth@arcor.de - 2016-11-19 03:14 -0800
      Re: Data Stack of Just Pointers? hughaguilar96@gmail.com - 2016-11-19 18:26 -0800
        Re: Data Stack of Just Pointers? trans <transfire@gmail.com> - 2016-11-19 18:50 -0800
          Re: Data Stack of Just Pointers? hughaguilar96@gmail.com - 2016-11-19 19:54 -0800
      Re: Data Stack of Just Pointers? trans <transfire@gmail.com> - 2016-11-19 18:52 -0800
        Re: Data Stack of Just Pointers? minforth@arcor.de - 2016-11-21 11:46 -0800
    Re: Data Stack of Just Pointers? trans <transfire@gmail.com> - 2016-11-19 13:57 -0800
  Re: Data Stack of Just Pointers? Jan Coombs <jenfhaomndgfwutc@murmic.plus.com> - 2016-11-19 11:27 +0000
  Re: Data Stack of Just Pointers? Ron Aaron <rambamist@gmail.com> - 2016-11-19 18:05 +0200
  Re: Data Stack of Just Pointers? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2016-11-20 13:29 +0000
    Re: Data Stack of Just Pointers? Spiros Bousbouras <spibou@gmail.com> - 2016-11-20 15:43 +0000
    Re: Data Stack of Just Pointers? Ron Aaron <rambamist@gmail.com> - 2016-11-20 19:06 +0200
      Re: Data Stack of Just Pointers? Ron Aaron <rambamist@gmail.com> - 2016-11-21 09:09 +0200
        Re: Data Stack of Just Pointers? Paul Rubin <no.email@nospam.invalid> - 2016-11-20 23:17 -0800
          Re: Data Stack of Just Pointers? Ron Aaron <rambamist@gmail.com> - 2016-11-21 09:22 +0200
        Re: Data Stack of Just Pointers? albert@cherry.spenarnc.xs4all.nl (Albert van der Horst) - 2016-11-21 11:12 +0100
          Re: Data Stack of Just Pointers? Ron Aaron <rambamist@gmail.com> - 2016-11-21 12:17 +0200
            Re: Data Stack of Just Pointers? Paul Rubin <no.email@nospam.invalid> - 2016-11-21 10:45 -0800
              Re: Data Stack of Just Pointers? Ron Aaron <rambamist@gmail.com> - 2016-11-21 21:22 +0200
                Re: Data Stack of Just Pointers? Paul Rubin <no.email@nospam.invalid> - 2016-11-21 17:28 -0800
                Re: Data Stack of Just Pointers? Ron Aaron <rambamist@gmail.com> - 2016-11-22 06:49 +0200
                Re: Data Stack of Just Pointers? Paul Rubin <no.email@nospam.invalid> - 2016-11-21 21:13 -0800
                Re: Data Stack of Just Pointers? franck.bensusan@gmail.com - 2016-12-21 13:48 -0800
        Re: Data Stack of Just Pointers? Cecil Bayona <cbayona@cbayona.com> - 2016-11-21 13:22 -0600
          Re: Data Stack of Just Pointers? "Robert L." <No_spamming@noWhere_7073.org> - 2016-11-22 01:53 +0000
            Re: Data Stack of Just Pointers? Cecil Bayona <cbayona@cbayona.com> - 2016-11-21 21:16 -0600
          Re: Data Stack of Just Pointers? Ron Aaron <rambamist@gmail.com> - 2016-11-22 07:01 +0200
        Re: Data Stack of Just Pointers? "Robert L." <No_spamming@noWhere_7073.org> - 2016-11-22 11:37 +0000

csiph-web