3 * PVW: Bugfixes for optional use of CHR constraints in rule guards.
7 * PVW: Optional use of CHR constraints in rule guards.
11 * TS: Bug fix in compiler_errors.pl.
15 * TS: Bug fix in occurrence subsumption by Jon Sneyers.
19 * TS: New preprocessor feature.
21 * TS: Parametrization of experimental chr_identifier type.
27 * TS: Stronger static type checking.
29 * TS: Omitted buggy FD analysis from bootstrapping process.
35 * TS: Experimental chr_identifier type.
39 * TS: Allow for empty type definitions aka phantom types. These are
40 useful for some type-level tricks. A warning is issued so the
41 user can check whether a phantom type is intended. No other
42 phantom type-specific checks are in place yet.
44 * TS: Fixed static type checking of built-in types.
48 * TS: The dense_int type can now appear on the rhs of type alias
53 * TS: Fixed bug concerning matchings between ground and possibly
58 * TS: Fixed a bug in code generation, overeager removal of a clause.
62 * TS: Refactored some code.
66 * TS: Add exception handler to initialize chr_leash in new threads.
70 * TS: Bug fix for programs in debugging mode.
74 * JW: Fixed make clean
75 * JW: Enlarged stacks to make build succeed
79 * JW: Add target ln-install
83 * TS: Fixed wrong arities in not inlined predicates. Mike Elston.
87 * TS: Code clean-up, more inlining, only generate used imports.
91 * TS: Inlining and more specialization of auxiliary predicates.
95 * TS: Fixed bug for constraints without rules in debug mode.
97 * TS: Compiler clean-up
99 * TS: Experimental var_assoc_store.
104 * TS: Various minor code generation improvements, including smaller
109 * TS: Absolutely no lock checking when check_guard_bindings is disabled.
113 * TS: Minor optimizations for (-) arguments.
115 * TS: Important optimization for awakening fewer suspended constraints
119 * TS: Fixed typo in static type checker.
121 * TS: Documented static and dynamic type checking.
125 * TS: Fixed bug (type alias related) in static type checker. Mike Elston.
127 * TS: Added static type checking on variable matching in rule heads.
129 * TS: Added static type checking on CHR constraints in rule bodies.
133 * TS: New (limited) compile time type checking of rule heads.
137 * TS: New experimental robustness feature in debug mode:
138 runtime type checking of CHR constraints.
142 * TS: Minor bug fixes.
146 * TS: Improved performance of ai_observation_analysis,
147 mainly via additional tabling and passive declarations.
151 * TS: Disabled some code only intended for SICStus.
153 * TS: Fixed bug in removal of constraints. Spotted by Leslie De Koninck.
157 * TS: Next fix to tracer. Cconstraints in propagation
158 rules are shown in textual order.
162 * TS: Next few fixes to tracer. Constraints in simpagation rules
163 are now shown on the right side of the backslash.
167 * TS: Synchronization with SICStus version of K.U.Leuven CHR.
169 * TS: First few fixes to tracer. Cconstraints in simplification
170 rules are shown in textual order. Constraint insertions
175 * TS: Termination bug fixed in guard_entailment.
177 * TS: Runtime library predicate run_suspensions is now specialized
178 per constraint, avoiding requirement of fixed suspension layout.
180 * TS: Further update to suspension term layout. Only constraints for
181 which the propagation history is used get a history field.
185 * TS: Ignore propagation rules with trivial body 'true'.
189 * TS: Guard entailment now first simplifies the formula it processes,
190 in order to reduce the number of disjunctions, to obtain a smaller
195 * TS: Bug fix by Jon Sneyers: type aliases now support built-in types.
196 Spotted by Mike Elston.
198 * TS: Small refactorings based on Ciao port experience.
200 * TS: Removed -singleton stylecheck option now that portray_clause
201 prints singleton variables as _.
205 * JW: Make library(chr) load its private stuff silent.
209 * TS: Bug fix: too many guards were locked.
213 * TS: Most runtime library predicates are now specialized
214 per constraint, avoiding generic =.. and lists code.
216 Mayor update to suspension term layout. Layout may now
217 differ from one constraint to the other. Some unused suspension
218 fields (continuation goal and generation number) are omitted.
219 Further analysis can remove more fields.
221 Default store constraints now each have
222 their own global variable: a list of all the suspensions.
223 Removal from this list is now O(1) thanks to setarg/1 and
224 back pointers in the suspension terms. This can cause time
225 time complexity improvements in solvers that always have
226 variable indexing on their constraints.
228 Ground, non-indexed constraints are now removed from
229 their global list store in O(1), as for the default store.
231 Minor bug fixes in a number of places.
235 * TS: Fixed subtle bug in ai_observation analysis,
236 that caused goal sequences to only generate
237 the optimistic default answer pattern, leading
238 to invalid 'not observed' conclusions.
239 * TS: Variable indexing/suspension analysis now ignores functor/3
240 in guards. Could be extended to other built-ins
241 that cause an error when arguments are not
242 properly instantiated.
246 * TS: Renamed global variable id to chr_id in chr_runtime.pl.
249 * JS: Synchronization with experimental version:
250 - minor optimizations, e.g. efficient lookups with statically known
252 - new alternative syntax for passive declarations
253 - new dense_int built-in type + underlying store
254 - new type alias definitions, like in Mercury
257 * BD: small changes in chr_compiler_options.pl and chr_translate.chr
258 affecting only the SICStus port
261 * BD: lots of changes related to porting to SICStus
262 * TS: Now exception/3 hook is only used in SWI-Prolog
266 * TS: Use exception/3 hook to catch undefined
267 global variables of chr_runtime.pl and CHR modules,
268 for multi-threaded programs and saved states.
272 * JW: Fix "make check" path issues.
273 * TS: Removed all is_chr_file tests when loading file.
277 * BD: chr_swi.pl: option(optimize --> :- chr_option(optimize
278 * TS: Removed obsolete experimental optimization option.
279 * TS: Correctly report variable pragmas!
280 * TS: No constraints declared is no longer a special case.
284 * BD: chr_swi.pl - use_module(hprolog added for SICStus port
285 * TS: Removed operator declaration for '::'. No longer used.
289 * TS: Removed chr_constraints declaration again, in favor
290 of only the chr_constraint declaration and modified
291 documentation accordingly.
292 * TS: Modified documentation based on recommendations of Bart Demoen.
293 * TS: Added chr_info/3 predicate to chr_compiler_errors, as suggested by
294 Jon Sneyers. Now print banner on calling compiler.
298 * TS: warnings are now written to user_error stream.
302 * TS: option and constraints declarations are now deprecated. They
303 are replaced by chr_option and chr_constraint(s).
304 * TR: Made an interface for warnings and errors. Errors now implemented
306 * TR: Revised documentation.
309 * BD: chr_translate.chr, chr_translate_bootstrap2.chr
310 mutables "abstracted"
311 * BD: chr_translate_bootstrap1.chr
312 atomic_concat - some duplicate code of it is in more than one file :-(
313 create_get_mutable definitions if-deffed
314 verbosity_on/0 for porting
316 definitions of init_store/2, get_store/2, update_store/2
317 and of make_init_store_goal/make_get_store_goal/make_update_store_goal
318 removed prolog_flag/3 (seemed nowhere used)
319 chr_translate_bootstrap2.chr
320 make_init_store_goal/make_get_store_goal/make_update_store_goal introduced
321 verbosity_on/0 for porting
322 chr_translate_bootstrap.pl
323 atom_concat -> atomic_concat
324 verbosity_on/0 for porting
325 conditional import van library(terms)
327 make_init_store_goal etc. introduced
328 create_get_mutable_ref wherever needed (chr_translate*)
332 * BD: chr_runtime.pl:
334 included contents of chr_debug.pl
336 create_mutable changed into 'chr create_mutable'
337 got rid of explicit inlining and did it by goal expansion
338 inlining also of 'chr default_store'
340 removed :- use_module(chr(chr_debug))
341 module header: version for SICStus
342 * BD: chr_debug.pl: emptied
343 * BD: chr_translate.chr:
344 system specific declarations factored out in insert_declarations
345 changed two atom_concat/3 into atomic_concat/3 (because arg 2 was sometimes an int)
346 * BD: chr_compiler_utility.pl:
347 put atomic_concat/3 there
348 adapted atom_concat_list/2 to use it
349 * BD: chr_swi_bootstrap.pl:
350 introduced chr_swi_bootstrap/2 for ease of porting
351 exported also chr_compile/3
352 porting code for get_time stuff/read_term/absolute_file_name
353 * BD: builtins.pl, a_star.pl, clean_code.pl:
358 * BD: hprolog.pl: removed strip_attributes/2 and restore_attributes/2
361 * BD: chr_swi.pl: Removed code that took Handler for Module (in chr_expand(end_of_file)
362 Added :- chr_option(_,_) with same meaning as option(_,_)
363 is_chr_file: .chr is no longer a recognised suffix
364 added use_module(library(lists))
365 changed calls to source_location/2 into prolog_load_context/2
366 * BD: chr_translate.chr: chr_translate/2: added end_of_file to translated program
367 adapted SICStus compatibility message
368 made :- chr_option(_,_) available
369 changed precedence of + - ? to 980 (these ops are
370 probably not local enough to the module)
374 * TS: Further synchronization with hProlog.
378 * TS: Removed dead code in guard_entailment.chr
379 * TS: Fixed performance bug: now lookup is indexed
380 on maximal number of arguments.
381 * TS: Removed some redundant intermediate predicates
383 * TS: It is now possible to disable the printing
384 of the CHR constraint store per module,
385 through the option toplevel_show_store on/off
386 * TS: Synchronized with hProlog
387 * TS: bug fix in functional dependency analysis
391 * TS: Removed two dead predicates in chr_translate.chr
392 and hooked up the late_storage_analysis
393 that was being bypassed.
394 * TS: Renamed global_term_ref_1 to default_store.
395 * TS: Removed redundant predicate values_ht.
396 * TS: Compiler no longer generates dead code for never stored constraints,
397 i.e. attach/detach predicates.
398 This reduces the generated .pl by about 700 lines.
402 * TS: Two more bug fixes for constraints without
403 active occurrences that trigger.
407 * TS: Small optimization of code for constraints
408 without any active occurrence.
409 * TS: Fixed bug caused by previous bug fix:
410 added only_ground_indexed_arguments/1 test
411 to separate out that meaning from may_trigger/1.
415 * TS: Removed strip_attributes code.
416 * TS: Fixed bug that causes new constraints to be added on triggering.
420 * TS: Two minor bug fixes.
424 * TS: Fixed bug due to overly aggressive inlining of get_mutable_value.
428 * JS: Compiled code is broken, if debug is off and optimize too.
429 Debug off now entails optimize on.
431 * TS: Some fixes of the documentation. Thanks to Bart Demoen
436 * TS: Synchronized with hProlog.
440 * TS: Added missing operator declarations for prefix (?).
444 * JW: import lists into chr_compiler_utility.pl
446 * JW: make message hook for query(yes) detect CHR global variables.
448 * JW: Exported pairlist_delete_eq/3 from pairlist and use this in
449 chr_hashtable_store.pl
453 * TS: Renamed pairlist:delete/3 to pairlist:pairlist_delete/3.
457 * TS: Extended more efficient ground matching code to
458 removed simpagation occurrence code.
462 * TS: New input verification: duplicate constraint declaration
463 now reported as an error. Requested by Mike Elston.
464 * TS: More efficient matching code for ground constraints
465 when matching an argument of a partner constraint with
467 * JS: Bug fix in guard simplification.
471 * TS: Factored out option functionality into separate module.
472 * TS: Factored out utility code into separate module.
476 * TS: Changed chr_show_store/1 to use print/1 instead of write/1.
480 * TS: Removed spurious and conflicting operator definitions
481 for +, - and ? as mode declarations.
485 * TS: Added find_chr_constraint/1 functionality.
489 * TS: Improved compiler scalability: use nb_setval/2 to
490 remember compiled code through backtracking over
491 compilation process instead of assert/1.
492 * TS: Removed spurious comma from file.
496 * TS: Added option to disable toplevel constraint store printing.
497 * TS: Slightly improved hash table constraint store implementation.
501 * JW: Added patch from Jon Sneyers.
505 * TS: Improved head reordering heuristic.
506 * TS: Added support primitive for alternate built-in solver dependency.
510 * TS: Fixed bug that causes wrong output in chr_show_store.
514 * TS: Fixed several bugs in generation of debugable code.
518 * JW: Cleanup integration in SWI-Prolog environment:
519 - Extended SWI-Prolog library ordsets. Renamed ord_delete/3 to
520 ord_del_element/3 and ord_difference/3 to ord_subtract/3 for
521 better compatibility.
522 - Renamed module find to chr_find to avoid name conflict and declared
523 preds as meta-predicate.
524 - Re-inserted and exported strip_attributes/2 and
525 restore_attributes/2 in hprolog.pl. Deleted hprolog: from
527 - Added dummy option declarations to bootstrap compiler.
528 - Fixed path problems in makefile (-p chr=.) and install new
530 - Fixed typo 'chr show_store' --> chr_show_store.
534 * JS: Added guard entailment optimizations and
535 new syntax for type and mode declarations.
539 * TS: Use prolog:message/3 hook to automatically print
540 contents of CHR constraint stores with query bindings
545 * TS: Bugfix in code generation. Reported by Lyosha Ilyukhin.
549 * TS: Updated hashtable stores. They now start small and expand.
553 * JW: Removed chr_pp: module prefixes
554 * JW: Updated Windows makefile.mak (more similar organisation, added check)
558 * TS: Added chr_hashtable_store library.
559 * TS: Added find library.
560 * TS: Added builtins library.
561 * TS: Added clean_code library.
562 * TS: Added binomial_heap library.
563 * TS: Added a_star library.
564 * TS: Added new intermediate bootstrapping step
565 * TS: Synchronized CHR compiler with most recent development version
569 "The new version of the compiler contains several new optimizations, both
570 fully automatic, such as the antimonotny-based delay avoidance (see
571 http://www.cs.kuleuven.be/publicaties/rapporten/cw/CW385.abs.html for
572 the technical report), and enabled by mode declarations (see CHR
573 documentation), such as hashtable-based constraint indexes."
577 * JW: Added chr_messages.pl. Make all debug messages use the print_message/2
578 interface to enable future embedding.
582 * JW: Added chr:debug_interact/3 hook. Defined in chr_swi.pl to void
583 showing constraints first as goal and then as CHR call.
584 * JW: Added chr:debug_event/2 hook. Defined in chr_swi.pl to make the
585 CHR debugger honour a skip command from the Prolog tracer.
589 * JW: Added b (break) to the CHR debugger.
590 * TS: added chr_expandable/2 clause for pragma/2
594 * JW: fixed reference to format_rule/2.
595 * JW: Use select/3 rather than delete/3 in diff/2 in Tests/zebra.pl
596 * TS: CHR translation now leaves CHR store empty
600 * JW: added :- use_module(library(chr)) to all examples.
601 * JW: mapped -O --> option(optimize, full).
602 * JW: introduced file-search-path `chr' for clarity and to enable running
603 make check from the local environment instead of the public installation.
604 * JW: mapped prolog flag generate_debug_info --> option(debug, on)
605 * JW: Replaced the chr -> pl step with term_expansion/2.
606 * JW: Moved insert_declarations/2 to chr_swi.pl
610 * JW: fixed Undefined procedure: chr_runtime:run_suspensions_loop_d/1
611 * TS: Added <space> for creep and shortened debug line prefix to CHR:
615 * JW: Use \+ \+ in chr_compile/3 to undo changes to the constraint
616 pool. Regression test suite using "make check" works again.
620 * TS: Added skip and ancestor debug commands
624 * TS: Added bootstrapping process for CHR compiler using CHR.
625 * TS: CHR compiler now uses CHR.
626 * TS: Fixed bug in compilation of multi-headed simpagation rules.
627 * TS: Cleaned up compiler.
628 * TS: Added analysis + optimization for never attached constraints.
629 * TS: Exploit uniqueness (functional dependency) results to detect
630 set semantics type simpagation rules where one rule can be passive
631 * TS: Compiler generates 'chr debug_event'/1 calls
632 * TS: Rudimentary support for debugging.
633 option(debug,on) causes a trace of CHR events to be printed
637 * JW: Fix operator handling.
641 * JW: Integrated new version from Tom Schrijvers.