Hi, Camm -- Thanks very much for the info about #@ and #!.
I'm afraid I don't have much of an idea about "real world" use for fixnums. In a local project, I think we take advantage of CCL's large fixnum range on 64-bit machines: ? most-positive-fixnum 1152921504606846975 ? most-negative-fixnum -1152921504606846976 ? (expt 2 60) 1152921504606846976 ? Of course, that's probably kind of irrelevant, since you were asking about fast fixnums rather than fixnums. I don't have much else to offer; sorry. I'll follow up with someone who may have more of a sense about your question. Thanks -- -- Matt Date: Mon, 22 Apr 2013 13:34:11 -0400 From: Camm Maguire <[email protected]> From: Camm Maguire <[email protected]> To: Matt Kaufmann <[email protected]> Subject: Re: #@ and #! readers References: <[email protected]> cc: [email protected] Date: Mon, 22 Apr 2013 13:34:11 -0400 In-Reply-To: <[email protected]> (Matt Kaufmann's message of "Fri, 19 Apr 2013 21:10:07 -0500") Message-ID: <[email protected]> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/23.4 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Greetings! Both of these appear to be unused, and set to the default dispatch macro which triggers an error. I think they are leftovers from earlier attempts to read the .data file (appended to each compiled .o to initialize lisp data) using the lisp reader. (see fasd.lisp, currently unused). These are safe to reset AFAICT. On a separate note, regarding fixnum arithmetic and the 'immediate fixnums' supported in cvs head, I've been looking into this on my new 64bit laptop. This platform can easily support a ~ 500000000 fixnum table below the .text start *without any conversions* back and forth between machine representations. In contrast, by default, an astronomically large table is set to the upper region of the 64bit address space which require shifts. Do you have any sense on what a good fast fixnum table subset size might be in real word use? Take care, Matt Kaufmann <[email protected]> writes: > Hi, Camm -- > > Readers for #@ and #! are defined in GCL 2.6.8pre, but we use them in > ACL2. Do you see any reason why I can't redefine these readers for > ACL2? Do you know what they do in GCL? > > >(get-dispatch-macro-character #\# #\@) > > #<compiled-function 000000000151b740> > > >(get-dispatch-macro-character #\# #\!) > > #<compiled-function 000000000151b740> > > > > > Thanks -- > -- Matt > > > > -- Camm Maguire [email protected] ========================================================================== "The earth is but one country, and mankind its citizens." -- Baha'u'llah _______________________________________________ Gcl-devel mailing list [email protected] https://lists.gnu.org/mailman/listinfo/gcl-devel
