On Wed, Aug 5, 2009 at 10:40 PM, Robert Dodierrobert_dodier@yahoo.com wrote:
Erik, thanks for looking into the problem.
--- On Wed, 8/5/09, Erik Huelsmann ehuels@gmail.com wrote:
in SPRDET.lisp, there's a top-level special declaration of the variable name X.
In ABCL, there's a non-trivial difference between evaluation of a special variable versus a local variable.
So, renaming the special variable could be a solution, but that would require a change on part of Maxima;
In this case, there is no problem with changing Maxima, e.g. rename X to *X* or just cut out the special declaration (glancing at the code, it seems the declaration may be unnecessary).
As you know, Maxima is an archaic program. This business about special X falls under the heading of "general clean-up" to me.
I'm thinking about how to revert the side effect at the end of the file compilation.
Well, there is a (DECLARE-TOP (UNSPECIAL X)) later on. I guess what is needed is an implementation of "unspecial" for ABCL.
Well, for the purpose of testing the performance impact of being able to declare "unspecial", I hacked into ABCL an UNDEFVAR primitive function and adjusted lmdcls.lisp accordingly.
The change takes ABCL from ~3300 seconds to ~ 2020 seconds evaluation time for Maxima's test suite.
However, I'm hesitant to provide the functionality as I've re-run the profiler and this is the new output:
35.8 211251 TMS 36.6 216078 TIMESIN 38.3 226175 SIMPTIMES 40.0 236302 GREAT 45.8 270172 KINDP 59.3 349696 MEVAL1 67.9 400737 MEVAL 77.4 456717 DLSF 84.7 499631 DLS 91.2 538251 DGRF 99.0 583971 SIMPLIFYA 100.0 590104 DGR
As a conclusion DGR and DLS are still among the hotest spots in the execution. So, I checked the disassembly again (which is how I discovered about X being taken to be special). From the disassembly, I gather that one of the DO variables (L) is taken to be special too. Searching through the Maxima sources I'm not finding where the specialness comes from...
It looks to me like - although I agree with you about the archaic nature of it - that Maxima would greatly benefit from (at least with ABCL) specials to be defined more locally: it's more Common Lisp if it does.
I'm thinking about not-implementing the make-unspecial, but the spec allows special declarations to be dropped at the end of a file compilation. I'm thinking about implementing that; it would seem to me it's more what users expect and doesn't add a non-standard feature.
I suppose that will eliminate the specialness of L in DGR too.
What would you say?
Bye,
Erik.