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Re: dead code or otherwise, was Alternative C compilers on x86_64 Linux?

From Kaz Kylheku <221-501-9011@kylheku.com>
Newsgroups comp.compilers
Subject Re: dead code or otherwise, was Alternative C compilers on x86_64 Linux?
Date 2016-09-09 19:57 +0000
Organization Aioe.org NNTP Server
Message-ID <16-09-022@comp.compilers> (permalink)
References (4 earlier) <16-09-015@comp.compilers> <16-09-016@comp.compilers> <16-09-017@comp.compilers> <16-09-018@comp.compilers> <16-09-021@comp.compilers>

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On 2016-09-09, George Neuner <gneuner2@comcast.net> wrote:
> On Fri, 9 Sep 2016 06:05:44 +0000 (UTC), Kaz Kylheku
><221-501-9011@kylheku.com> wrote:
>
>>On 2016-09-09, George Neuner <gneuner2@comcast.net> wrote:
>>> But like any good Usenet discussion, it (d)evolved into something more
>>> general.
>>>
>>> Not every language with a CASE like construct has C's limitations on
>>> specifying the alternatives.  Lisp certainly doesn't.
>>
>>Yes, it does, in fact. The labels in Lisp case are literals that are
>>embedded in the CASE syntax itself, and not evaluated. They are
>>compared to the input value using EQL equality. Duplicate cases
>>are a bug, which is not required to be diagnosed.
>
> Lisp does not restrict CASE "labels" to integers like C.  They can be
> any of [at least] symbols, characters, integers or booleans.
> And unlike C where booleans and characters are subsets of integer, in
> Lisp they are discrete types.  Additionally symbols are a reference
> type - a pointer to a structure.

At the low level it's fairly similar because EQL compares most of
those types as machine words, with the exception of integers
(two distinct bignum objects denoting the same integer are EQL).

If none of the case labels are bignums (case's usual case), then EQ can
be used, and then boils down to a switch on machine words.

All the same tricks can be used: jump table, tree-search.

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Thread

Alternative C compilers on x86_64 Linux? arnold@skeeve.com (Aharon Robbins) - 2016-09-02 03:01 +0000
  Re: Alternative C compilers on x86_64 Linux? jacobnavia <jacob@jacob.remcomp.fr> - 2016-09-05 00:20 +0200
    Re: Alternative C compilers on x86_64 Linux? alexfrunews@gmail.com - 2016-09-05 17:26 -0700
      Re: diagnosing C errors, was Alternative C compilers on x86_64 Linux? BartC <bc@freeuk.com> - 2016-09-09 12:31 +0100
        Re: diagnosing C errors, was Alternative C compilers on x86_64 Linux? Kaz Kylheku <221-501-9011@kylheku.com> - 2016-09-09 16:06 +0000
        Re: diagnosing C errors, was Alternative C compilers on x86_64 Linux? Hans-Peter Diettrich <DrDiettrich1@netscape.net> - 2016-09-10 00:38 +0200
  Re: Alternative C compilers on x86_64 Linux? Nemo <nemo@invalid.invalid> - 2016-09-04 18:32 -0400
  Re: Alternative C compilers on x86_64 Linux? Kaz Kylheku <221-501-9011@kylheku.com> - 2016-09-04 23:48 +0000
  Re: Alternative C compilers on x86_64 Linux? BartC <bc@freeuk.com> - 2016-09-05 13:19 +0100
    Re: Alternative C compilers on x86_64 Linux? Kaz Kylheku <221-501-9011@kylheku.com> - 2016-09-06 02:15 +0000
      Re: Alternative C compilers on x86_64 Linux? BartC <bc@freeuk.com> - 2016-09-06 21:35 +0100
        Re: dead code or otherwise, was Alternative C compilers on x86_64 Linux? George Neuner <gneuner2@comcast.net> - 2016-09-08 11:58 -0400
          Re: dead code or otherwise, was Alternative C compilers on x86_64 Linux? Kaz Kylheku <221-501-9011@kylheku.com> - 2016-09-08 22:54 +0000
            Re: dead code or otherwise, was Alternative C compilers on x86_64 Linux? George Neuner <gneuner2@comcast.net> - 2016-09-09 00:51 -0400
              Re: dead code or otherwise, was Alternative C compilers on x86_64 Linux? Kaz Kylheku <221-501-9011@kylheku.com> - 2016-09-09 06:05 +0000
                Re: dead code or otherwise, was Alternative C compilers on x86_64 Linux? George Neuner <gneuner2@comcast.net> - 2016-09-09 14:02 -0400
                Re: dead code or otherwise, was Alternative C compilers on x86_64 Linux? Kaz Kylheku <221-501-9011@kylheku.com> - 2016-09-09 19:57 +0000
      Re: duplicate cases, was Alternative C compilers on x86_64 Linux? Andy Walker <anw@cuboid.co.uk> - 2016-09-07 17:01 +0100
  Re: Alternative C compilers on x86_64 Linux? Florian Weimer <fw@deneb.enyo.de> - 2016-09-05 20:06 +0200
  Re: Alternative C compilers on x86_64 Linux? alexfrunews@gmail.com - 2016-09-05 17:22 -0700
    Re: Alternative C compilers on x86_64 Linux? Kaz Kylheku <221-501-9011@kylheku.com> - 2016-09-06 02:18 +0000
  Re: Alternative C compilers on x86_64 Linux? rockbrentwood@gmail.com - 2016-09-07 17:00 -0700
  Re: Alternative C compilers on x86_64 Linux? arnold@skeeve.com (Aharon Robbins) - 2016-09-12 18:42 +0000
    Re: Alternative C compilers on x86_64 Linux? BartC <bc@freeuk.com> - 2016-09-12 22:37 +0100
      Re: Alternative C compilers on x86_64 Linux? arnold@skeeve.com (Aharon Robbins) - 2016-09-13 17:35 +0000
        Re: Alternative C compilers on x86_64 Linux? arnold@skeeve.com (Aharon Robbins) - 2016-09-14 18:14 +0000
  Re: Alternative C compilers on x86_64 Linux? rugxulo@gmail.com - 2016-09-26 15:29 -0700
    Re: Alternative C compilers on x86_64 Linux? arnold@skeeve.com (Aharon Robbins) - 2016-09-27 05:40 +0000
      Re: Alternative C compilers on x86_64 Linux? rugxulo@gmail.com - 2016-09-27 16:36 -0700
        Re: Alternative C compilers on x86_64 Linux? BartC <bc@freeuk.com> - 2016-09-28 18:16 +0100
          Re: Alternative C compilers on x86_64 Linux? BartC <bc@freeuk.com> - 2016-09-29 14:03 +0100
            Re: Alternative C compilers on x86_64 Linux? George Neuner <gneuner2@comcast.net> - 2016-09-29 22:57 -0400
            Re: Alternative C compilers on x86_64 Linux? Hans-Peter Diettrich <DrDiettrich1@netscape.net> - 2016-09-30 05:03 +0200
              Re: Alternative C compilers on x86_64 Linux? BartC <bc@freeuk.com> - 2016-09-30 12:00 +0100
                Re: Alternative C compilers on x86_64 Linux? Hans-Peter Diettrich <DrDiettrich1@netscape.net> - 2016-09-30 20:15 +0200
                Re: Alternative C compilers on x86_64 Linux? BartC <bc@freeuk.com> - 2016-10-01 22:17 +0100
            Re: Alternative C compilers on x86_64 Linux? BartC <bc@freeuk.com> - 2016-09-30 12:28 +0100
              Re: Alternative C compilers on x86_64 Linux? BartC <bc@freeuk.com> - 2016-10-17 22:49 +0100
        Re: Alternative C compilers on x86_64 Linux? George Neuner <gneuner2@comcast.net> - 2016-09-28 21:24 -0400
      Re: Alternative C compilers on x86_64 Linux? George Neuner <gneuner2@comcast.net> - 2016-09-28 01:01 -0400
        Re: Alternative C compilers on x86_64 Linux? arnold@skeeve.com (Aharon Robbins) - 2016-09-29 02:55 +0000
      Re: Alternative C compilers on x86_64 Linux? arnold@skeeve.com - 2016-09-29 05:30 -0600
        Re: Alternative C compilers on x86_64 Linux? arnold@skeeve.com (Aharon Robbins) - 2016-09-30 10:13 +0000

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