3 * TS: Fixed bug concerning matchings between ground and possibly
8 * TS: Fixed a bug in code generation, overeager removal of a clause.
12 * TS: Refactored some code.
16 * TS: Add exception handler to initialize chr_leash in new threads.
20 * TS: Bug fix for programs in debugging mode.
24 * JW: Fixed make clean
25 * JW: Enlarged stacks to make build succeed
29 * JW: Add target ln-install
33 * TS: Fixed wrong arities in not inlined predicates. Mike Elston.
37 * TS: Code clean-up, more inlining, only generate used imports.
41 * TS: Inlining and more specialization of auxiliary predicates.
45 * TS: Fixed bug for constraints without rules in debug mode.
47 * TS: Compiler clean-up
49 * TS: Experimental var_assoc_store.
54 * TS: Various minor code generation improvements, including smaller
59 * TS: Absolutely no lock checking when check_guard_bindings is disabled.
63 * TS: Minor optimizations for (-) arguments.
65 * TS: Important optimization for awakening fewer suspended constraints
69 * TS: Fixed typo in static type checker.
71 * TS: Documented static and dynamic type checking.
75 * TS: Fixed bug (type alias related) in static type checker. Mike Elston.
77 * TS: Added static type checking on variable matching in rule heads.
79 * TS: Added static type checking on CHR constraints in rule bodies.
83 * TS: New (limited) compile time type checking of rule heads.
87 * TS: New experimental robustness feature in debug mode:
88 runtime type checking of CHR constraints.
92 * TS: Minor bug fixes.
96 * TS: Improved performance of ai_observation_analysis,
97 mainly via additional tabling and passive declarations.
101 * TS: Disabled some code only intended for SICStus.
103 * TS: Fixed bug in removal of constraints. Spotted by Leslie De Koninck.
107 * TS: Next fix to tracer. Cconstraints in propagation
108 rules are shown in textual order.
112 * TS: Next few fixes to tracer. Constraints in simpagation rules
113 are now shown on the right side of the backslash.
117 * TS: Synchronization with SICStus version of K.U.Leuven CHR.
119 * TS: First few fixes to tracer. Cconstraints in simplification
120 rules are shown in textual order. Constraint insertions
125 * TS: Termination bug fixed in guard_entailment.
127 * TS: Runtime library predicate run_suspensions is now specialized
128 per constraint, avoiding requirement of fixed suspension layout.
130 * TS: Further update to suspension term layout. Only constraints for
131 which the propagation history is used get a history field.
135 * TS: Ignore propagation rules with trivial body 'true'.
139 * TS: Guard entailment now first simplifies the formula it processes,
140 in order to reduce the number of disjunctions, to obtain a smaller
145 * TS: Bug fix by Jon Sneyers: type aliases now support built-in types.
146 Spotted by Mike Elston.
148 * TS: Small refactorings based on Ciao port experience.
150 * TS: Removed -singleton stylecheck option now that portray_clause
151 prints singleton variables as _.
155 * JW: Make library(chr) load its private stuff silent.
159 * TS: Bug fix: too many guards were locked.
163 * TS: Most runtime library predicates are now specialized
164 per constraint, avoiding generic =.. and lists code.
166 Mayor update to suspension term layout. Layout may now
167 differ from one constraint to the other. Some unused suspension
168 fields (continuation goal and generation number) are omitted.
169 Further analysis can remove more fields.
171 Default store constraints now each have
172 their own global variable: a list of all the suspensions.
173 Removal from this list is now O(1) thanks to setarg/1 and
174 back pointers in the suspension terms. This can cause time
175 time complexity improvements in solvers that always have
176 variable indexing on their constraints.
178 Ground, non-indexed constraints are now removed from
179 their global list store in O(1), as for the default store.
181 Minor bug fixes in a number of places.
185 * TS: Fixed subtle bug in ai_observation analysis,
186 that caused goal sequences to only generate
187 the optimistic default answer pattern, leading
188 to invalid 'not observed' conclusions.
189 * TS: Variable indexing/suspension analysis now ignores functor/3
190 in guards. Could be extended to other built-ins
191 that cause an error when arguments are not
192 properly instantiated.
196 * TS: Renamed global variable id to chr_id in chr_runtime.pl.
199 * JS: Synchronization with experimental version:
200 - minor optimizations, e.g. efficient lookups with statically known
202 - new alternative syntax for passive declarations
203 - new dense_int built-in type + underlying store
204 - new type alias definitions, like in Mercury
207 * BD: small changes in chr_compiler_options.pl and chr_translate.chr
208 affecting only the SICStus port
211 * BD: lots of changes related to porting to SICStus
212 * TS: Now exception/3 hook is only used in SWI-Prolog
216 * TS: Use exception/3 hook to catch undefined
217 global variables of chr_runtime.pl and CHR modules,
218 for multi-threaded programs and saved states.
222 * JW: Fix "make check" path issues.
223 * TS: Removed all is_chr_file tests when loading file.
227 * BD: chr_swi.pl: option(optimize --> :- chr_option(optimize
228 * TS: Removed obsolete experimental optimization option.
229 * TS: Correctly report variable pragmas!
230 * TS: No constraints declared is no longer a special case.
234 * BD: chr_swi.pl - use_module(hprolog added for SICStus port
235 * TS: Removed operator declaration for '::'. No longer used.
239 * TS: Removed chr_constraints declaration again, in favor
240 of only the chr_constraint declaration and modified
241 documentation accordingly.
242 * TS: Modified documentation based on recommendations of Bart Demoen.
243 * TS: Added chr_info/3 predicate to chr_compiler_errors, as suggested by
244 Jon Sneyers. Now print banner on calling compiler.
248 * TS: warnings are now written to user_error stream.
252 * TS: option and constraints declarations are now deprecated. They
253 are replaced by chr_option and chr_constraint(s).
254 * TR: Made an interface for warnings and errors. Errors now implemented
256 * TR: Revised documentation.
259 * BD: chr_translate.chr, chr_translate_bootstrap2.chr
260 mutables "abstracted"
261 * BD: chr_translate_bootstrap1.chr
262 atomic_concat - some duplicate code of it is in more than one file :-(
263 create_get_mutable definitions if-deffed
264 verbosity_on/0 for porting
266 definitions of init_store/2, get_store/2, update_store/2
267 and of make_init_store_goal/make_get_store_goal/make_update_store_goal
268 removed prolog_flag/3 (seemed nowhere used)
269 chr_translate_bootstrap2.chr
270 make_init_store_goal/make_get_store_goal/make_update_store_goal introduced
271 verbosity_on/0 for porting
272 chr_translate_bootstrap.pl
273 atom_concat -> atomic_concat
274 verbosity_on/0 for porting
275 conditional import van library(terms)
277 make_init_store_goal etc. introduced
278 create_get_mutable_ref wherever needed (chr_translate*)
282 * BD: chr_runtime.pl:
284 included contents of chr_debug.pl
286 create_mutable changed into 'chr create_mutable'
287 got rid of explicit inlining and did it by goal expansion
288 inlining also of 'chr default_store'
290 removed :- use_module(chr(chr_debug))
291 module header: version for SICStus
292 * BD: chr_debug.pl: emptied
293 * BD: chr_translate.chr:
294 system specific declarations factored out in insert_declarations
295 changed two atom_concat/3 into atomic_concat/3 (because arg 2 was sometimes an int)
296 * BD: chr_compiler_utility.pl:
297 put atomic_concat/3 there
298 adapted atom_concat_list/2 to use it
299 * BD: chr_swi_bootstrap.pl:
300 introduced chr_swi_bootstrap/2 for ease of porting
301 exported also chr_compile/3
302 porting code for get_time stuff/read_term/absolute_file_name
303 * BD: builtins.pl, a_star.pl, clean_code.pl:
308 * BD: hprolog.pl: removed strip_attributes/2 and restore_attributes/2
311 * BD: chr_swi.pl: Removed code that took Handler for Module (in chr_expand(end_of_file)
312 Added :- chr_option(_,_) with same meaning as option(_,_)
313 is_chr_file: .chr is no longer a recognised suffix
314 added use_module(library(lists))
315 changed calls to source_location/2 into prolog_load_context/2
316 * BD: chr_translate.chr: chr_translate/2: added end_of_file to translated program
317 adapted SICStus compatibility message
318 made :- chr_option(_,_) available
319 changed precedence of + - ? to 980 (these ops are
320 probably not local enough to the module)
324 * TS: Further synchronization with hProlog.
328 * TS: Removed dead code in guard_entailment.chr
329 * TS: Fixed performance bug: now lookup is indexed
330 on maximal number of arguments.
331 * TS: Removed some redundant intermediate predicates
333 * TS: It is now possible to disable the printing
334 of the CHR constraint store per module,
335 through the option toplevel_show_store on/off
336 * TS: Synchronized with hProlog
337 * TS: bug fix in functional dependency analysis
341 * TS: Removed two dead predicates in chr_translate.chr
342 and hooked up the late_storage_analysis
343 that was being bypassed.
344 * TS: Renamed global_term_ref_1 to default_store.
345 * TS: Removed redundant predicate values_ht.
346 * TS: Compiler no longer generates dead code for never stored constraints,
347 i.e. attach/detach predicates.
348 This reduces the generated .pl by about 700 lines.
352 * TS: Two more bug fixes for constraints without
353 active occurrences that trigger.
357 * TS: Small optimization of code for constraints
358 without any active occurrence.
359 * TS: Fixed bug caused by previous bug fix:
360 added only_ground_indexed_arguments/1 test
361 to separate out that meaning from may_trigger/1.
365 * TS: Removed strip_attributes code.
366 * TS: Fixed bug that causes new constraints to be added on triggering.
370 * TS: Two minor bug fixes.
374 * TS: Fixed bug due to overly aggressive inlining of get_mutable_value.
378 * JS: Compiled code is broken, if debug is off and optimize too.
379 Debug off now entails optimize on.
381 * TS: Some fixes of the documentation. Thanks to Bart Demoen
386 * TS: Synchronized with hProlog.
390 * TS: Added missing operator declarations for prefix (?).
394 * JW: import lists into chr_compiler_utility.pl
396 * JW: make message hook for query(yes) detect CHR global variables.
398 * JW: Exported pairlist_delete_eq/3 from pairlist and use this in
399 chr_hashtable_store.pl
403 * TS: Renamed pairlist:delete/3 to pairlist:pairlist_delete/3.
407 * TS: Extended more efficient ground matching code to
408 removed simpagation occurrence code.
412 * TS: New input verification: duplicate constraint declaration
413 now reported as an error. Requested by Mike Elston.
414 * TS: More efficient matching code for ground constraints
415 when matching an argument of a partner constraint with
417 * JS: Bug fix in guard simplification.
421 * TS: Factored out option functionality into separate module.
422 * TS: Factored out utility code into separate module.
426 * TS: Changed chr_show_store/1 to use print/1 instead of write/1.
430 * TS: Removed spurious and conflicting operator definitions
431 for +, - and ? as mode declarations.
435 * TS: Added find_chr_constraint/1 functionality.
439 * TS: Improved compiler scalability: use nb_setval/2 to
440 remember compiled code through backtracking over
441 compilation process instead of assert/1.
442 * TS: Removed spurious comma from file.
446 * TS: Added option to disable toplevel constraint store printing.
447 * TS: Slightly improved hash table constraint store implementation.
451 * JW: Added patch from Jon Sneyers.
455 * TS: Improved head reordering heuristic.
456 * TS: Added support primitive for alternate built-in solver dependency.
460 * TS: Fixed bug that causes wrong output in chr_show_store.
464 * TS: Fixed several bugs in generation of debugable code.
468 * JW: Cleanup integration in SWI-Prolog environment:
469 - Extended SWI-Prolog library ordsets. Renamed ord_delete/3 to
470 ord_del_element/3 and ord_difference/3 to ord_subtract/3 for
471 better compatibility.
472 - Renamed module find to chr_find to avoid name conflict and declared
473 preds as meta-predicate.
474 - Re-inserted and exported strip_attributes/2 and
475 restore_attributes/2 in hprolog.pl. Deleted hprolog: from
477 - Added dummy option declarations to bootstrap compiler.
478 - Fixed path problems in makefile (-p chr=.) and install new
480 - Fixed typo 'chr show_store' --> chr_show_store.
484 * JS: Added guard entailment optimizations and
485 new syntax for type and mode declarations.
489 * TS: Use prolog:message/3 hook to automatically print
490 contents of CHR constraint stores with query bindings
495 * TS: Bugfix in code generation. Reported by Lyosha Ilyukhin.
499 * TS: Updated hashtable stores. They now start small and expand.
503 * JW: Removed chr_pp: module prefixes
504 * JW: Updated Windows makefile.mak (more similar organisation, added check)
508 * TS: Added chr_hashtable_store library.
509 * TS: Added find library.
510 * TS: Added builtins library.
511 * TS: Added clean_code library.
512 * TS: Added binomial_heap library.
513 * TS: Added a_star library.
514 * TS: Added new intermediate bootstrapping step
515 * TS: Synchronized CHR compiler with most recent development version
519 "The new version of the compiler contains several new optimizations, both
520 fully automatic, such as the antimonotny-based delay avoidance (see
521 http://www.cs.kuleuven.be/publicaties/rapporten/cw/CW385.abs.html for
522 the technical report), and enabled by mode declarations (see CHR
523 documentation), such as hashtable-based constraint indexes."
527 * JW: Added chr_messages.pl. Make all debug messages use the print_message/2
528 interface to enable future embedding.
532 * JW: Added chr:debug_interact/3 hook. Defined in chr_swi.pl to void
533 showing constraints first as goal and then as CHR call.
534 * JW: Added chr:debug_event/2 hook. Defined in chr_swi.pl to make the
535 CHR debugger honour a skip command from the Prolog tracer.
539 * JW: Added b (break) to the CHR debugger.
540 * TS: added chr_expandable/2 clause for pragma/2
544 * JW: fixed reference to format_rule/2.
545 * JW: Use select/3 rather than delete/3 in diff/2 in Tests/zebra.pl
546 * TS: CHR translation now leaves CHR store empty
550 * JW: added :- use_module(library(chr)) to all examples.
551 * JW: mapped -O --> option(optimize, full).
552 * JW: introduced file-search-path `chr' for clarity and to enable running
553 make check from the local environment instead of the public installation.
554 * JW: mapped prolog flag generate_debug_info --> option(debug, on)
555 * JW: Replaced the chr -> pl step with term_expansion/2.
556 * JW: Moved insert_declarations/2 to chr_swi.pl
560 * JW: fixed Undefined procedure: chr_runtime:run_suspensions_loop_d/1
561 * TS: Added <space> for creep and shortened debug line prefix to CHR:
565 * JW: Use \+ \+ in chr_compile/3 to undo changes to the constraint
566 pool. Regression test suite using "make check" works again.
570 * TS: Added skip and ancestor debug commands
574 * TS: Added bootstrapping process for CHR compiler using CHR.
575 * TS: CHR compiler now uses CHR.
576 * TS: Fixed bug in compilation of multi-headed simpagation rules.
577 * TS: Cleaned up compiler.
578 * TS: Added analysis + optimization for never attached constraints.
579 * TS: Exploit uniqueness (functional dependency) results to detect
580 set semantics type simpagation rules where one rule can be passive
581 * TS: Compiler generates 'chr debug_event'/1 calls
582 * TS: Rudimentary support for debugging.
583 option(debug,on) causes a trace of CHR events to be printed
587 * JW: Fix operator handling.
591 * JW: Integrated new version from Tom Schrijvers.