Dejan Jovanović [Mon, 26 Mar 2012 19:42:25 +0000 (19:42 +0000)]
Global registry of SAT solvers, where they are registered at compile time. The available SAT solvers can be seen with the --show-sat-solvers option.
Dejan Jovanović [Mon, 26 Mar 2012 14:22:38 +0000 (14:22 +0000)]
More cleaning up.
Dejan Jovanović [Mon, 26 Mar 2012 12:29:21 +0000 (12:29 +0000)]
more datail from the build failure
Dejan Jovanović [Mon, 26 Mar 2012 12:25:12 +0000 (12:25 +0000)]
with a small fix
Dejan Jovanović [Mon, 26 Mar 2012 12:23:54 +0000 (12:23 +0000)]
forgot to commit this one, fixing build errors
Dejan Jovanović [Sun, 25 Mar 2012 20:45:45 +0000 (20:45 +0000)]
moving minisat implementation into their respective directories (regular and bv)
Dejan Jovanović [Sun, 25 Mar 2012 20:12:07 +0000 (20:12 +0000)]
sat_module.h,cpp -> sat_solver.h,cpp (as intended)
Dejan Jovanović [Sun, 25 Mar 2012 20:04:43 +0000 (20:04 +0000)]
sat.h,cpp -> theory_proxy.h,cpp (this is what it defines)
Dejan Jovanović [Sat, 24 Mar 2012 21:18:37 +0000 (21:18 +0000)]
a cute script to make a video of development from the svn logs
Tim King [Fri, 23 Mar 2012 23:06:29 +0000 (23:06 +0000)]
Removed the variableRemovalEnabled option and d_removedRows from TheoryArith. This had been disabled for several months.
Dejan Jovanović [Thu, 22 Mar 2012 23:09:03 +0000 (23:09 +0000)]
* improving arithmetic getEqualityStatus
* some sharing improvements based on model
Liana Hadarean [Thu, 22 Mar 2012 21:45:31 +0000 (21:45 +0000)]
Merged updated version of the bitvector theory:
* added simplification rewrites
Dejan Jovanović [Thu, 22 Mar 2012 20:40:41 +0000 (20:40 +0000)]
some improvements to the sharing mechanism/interface
Morgan Deters [Wed, 21 Mar 2012 20:51:02 +0000 (20:51 +0000)]
Disable nonclausal simplification for QF_SAT benchmarks by default.
(Can be overridden with --simplification=batch, for example.)
Morgan Deters [Fri, 9 Mar 2012 21:10:17 +0000 (21:10 +0000)]
Some work on the dump infrastructure to support portfolio work.
Dump("foo") << FooCommand(...);
now "dumps" the textual representation of the command (in the current
output language) to a file, IF dumping is on at configure-time, AND the
"muzzle" feature is off, AND the "foo" flag is turned on for the dump
stream during this run.
If it's a portfolio build, the above will also store the command in a
CommandSequence, IF the "foo" flag is turned on for the dump stream
during this run. This is done even if the muzzle is on.
This commit also cleans up some code that used the dump feature (in arrays,
particularly).
Morgan Deters [Fri, 9 Mar 2012 21:00:51 +0000 (21:00 +0000)]
fix a "lost command" bug and associated memory leak in SMT-LIBv1 parser due to an out-of-place parenthesis
Morgan Deters [Fri, 9 Mar 2012 20:30:15 +0000 (20:30 +0000)]
Strengthen minisat assertion regarding t-propagations that was unintentionally allowing a theory to propagate p and ~p at the same time (and the conflict was undetected, leading to an incorrect answer). Credit to Clark for finding this.
Morgan Deters [Fri, 9 Mar 2012 18:26:07 +0000 (18:26 +0000)]
minor fixes: to "make dist" in build directories with language bindings enabled; and to makefile standards conformance
Morgan Deters [Thu, 8 Mar 2012 19:06:08 +0000 (19:06 +0000)]
fix "make dist"
Dejan Jovanović [Thu, 8 Mar 2012 18:54:02 +0000 (18:54 +0000)]
Fixin the bug Clark found. In final check, enqueued propagations were not discharged.
Dejan Jovanović [Thu, 8 Mar 2012 02:33:37 +0000 (02:33 +0000)]
Removing QUICK_CHECK, and other unused ones, from the Theory::Effort.
Seems to be working better <http://church.cims.nyu.edu/regress-results/compare_jobs.php?job_id=3749&category=&p=5&reference_id=3739>, and should fix the failing cases in the regressions.
Removing one test case from the integer regress0.
François Bobot [Wed, 7 Mar 2012 22:29:39 +0000 (22:29 +0000)]
cdqueue : fix size(). Thank you Clark for spotting this silly mistake.
Morgan Deters [Wed, 7 Mar 2012 21:38:04 +0000 (21:38 +0000)]
fix some Java compatibility-layer interface problems; also fix some Mac OS X build issues
Dejan Jovanović [Tue, 6 Mar 2012 19:08:32 +0000 (19:08 +0000)]
updating the equality engine to be able to give explanations for terms that were not in the databas (queried by areEqual and areDisequal)
and it's a bit better
http://church.cims.nyu.edu/regress-results/compare_jobs.php?job_id=3738&category=&p=-1&reference_id=3731
Morgan Deters [Sat, 3 Mar 2012 23:29:20 +0000 (23:29 +0000)]
Changing the dependency checking; GMP is required (and sometimes must be explicitly linked in with -l) when using CLN. Fixes a bug on recent Debian that Francois reported. Hopefully this doesn't break anything..
Kshitij Bansal [Fri, 2 Mar 2012 23:43:50 +0000 (23:43 +0000)]
Remove some commented out code from sat.h
Tim King [Fri, 2 Mar 2012 23:37:06 +0000 (23:37 +0000)]
This commit merges in the changes from branches/arithmetic/refactor0
- Improved the checks in AssertLower and AssertUpper so that redundant bounds cause less work.
- Because of the above change, d_constantIntegerVariables now cannot have duplicate elements enqueued. This allows removing d_varsInDioSolver.
- Fix to an assertion in CDQueue.
- Implements a CDArithVarSet using a vector of booleans and CDList.
- Refactored ArithVar out of arith_utilities.h. Miscellaneous cleanup of arithmetic.
Dejan Jovanović [Fri, 2 Mar 2012 20:38:23 +0000 (20:38 +0000)]
CDMap -> CDHashMap
CDSet -> CDHashSet
Morgan Deters [Fri, 2 Mar 2012 20:12:44 +0000 (20:12 +0000)]
committing the TNode/Node fix that was in the kind-backend branch; there's still something fishy here, I think I need to merge in a few more things to support incrementality properly. But this fixes "make check" for now
Tim King [Fri, 2 Mar 2012 16:32:16 +0000 (16:32 +0000)]
Renamed CDQueue to CDTrailQueue and CDQueue2 to CDQueue. Small changes to function names and documentation.
Morgan Deters [Thu, 1 Mar 2012 14:48:04 +0000 (14:48 +0000)]
Partial merge from kind-backend branch, including Minisat and CNF work to
support incrementality.
Some clean-up work will likely follow, but the CNF/Minisat stuff should be
left pretty much untouched.
Expected performance change negligible; slightly better on memory:
http://church.cims.nyu.edu/regress-results/compare_jobs.php?job_id=3705&reference_id=3697&mode=&category=&p=5
Note that there are crashes, but that these are exhibited in the nightly
regression run too!
François Bobot [Thu, 1 Mar 2012 01:34:35 +0000 (01:34 +0000)]
cdqueue2 : cdlist that can be used like queue and can delete element that will never be restored
Tim King [Thu, 1 Mar 2012 00:38:37 +0000 (00:38 +0000)]
Fixed a copy paste error where a lower bound was looked up instead of an upper bound.
Liana Hadarean [Wed, 29 Feb 2012 20:33:43 +0000 (20:33 +0000)]
This should fix the debian build fails:
* removed bvpicosat directory as it is currently not used
Cleared some of the flurry of warnings my previous merge caused in src/prop/
Dejan Jovanović [Wed, 29 Feb 2012 20:06:21 +0000 (20:06 +0000)]
fixing bug310
* theories that are parametric and therefore need the combination framwork should be tagged as "parametric" in the kinds file
* default care graph computation was not sufficient, fixed
Morgan Deters [Wed, 29 Feb 2012 17:49:44 +0000 (17:49 +0000)]
consistency in how the Dump output stream is used
Tim King [Tue, 28 Feb 2012 21:26:35 +0000 (21:26 +0000)]
This commit merges in branches/arithmetic/internalbb up to revision 2831. This is a significant refactoring of code.
- r2820
-- Refactors Simplex so that it does significantly fewer functions.
-- Adds the LinearEqualityModule for handling update and pivotAndUpdate and other utility functions that require access to both the tableau and partial model.
-- Some of the code for propagation has moved to TheoryArith.
-r2826
-- Small changes to documentation and removes the no longer implemented deduceLowerBound() and deduceUpperBound().
- r2827
-- Adds isZero() to Rational. Adds cmp to DeltaRational.
- r2831
-- Refactored comparison to upper and lower in the partial model to use DeltaRational::cmp.
-- Refactored AssertUpper and AssertLower in TheoryArith to include functionality that has weaseled into TheoryArith::assertionCases.
Tim King [Tue, 28 Feb 2012 20:42:55 +0000 (20:42 +0000)]
Improves the arithmetic difference manager to delay any work until a shared term is added.
Morgan Deters [Tue, 28 Feb 2012 20:20:03 +0000 (20:20 +0000)]
fix theory "kinds" file documentation for allowed arity of operators
Tim King [Tue, 28 Feb 2012 20:13:02 +0000 (20:13 +0000)]
Adds the CDQueue class. This is a wrapper for combining a CDList<T> and a CDO<size_t> into a FIFO queue.
Morgan Deters [Tue, 28 Feb 2012 19:51:10 +0000 (19:51 +0000)]
Replace the sequence of hardcoded addTheory() calls with a use of the theory traits---with the effect that everything with a kinds file is registered as a theory. Eventually we may want a more dynamic way of selecting theory implementations, but for now we don't have a need for this. Expected performance impact: none. (This commit addresses and re-closes the reopened bug #307.)
Morgan Deters [Mon, 27 Feb 2012 22:51:53 +0000 (22:51 +0000)]
fixes to new-theory script; resolves bug #307
Dejan Jovanović [Sat, 25 Feb 2012 22:35:53 +0000 (22:35 +0000)]
ppAsert -> ppAssert
Liana Hadarean [Sat, 25 Feb 2012 18:23:10 +0000 (18:23 +0000)]
Refactored CnfStream to work with the bv theory Bitblaster:
* separated SatSolverInput interface class into two classes:
- TheoryProxy for the sat solver to communicate with the theories
- SatSolverInterface abstract class to communicate with the sat solver
* instead of using #ifdef typedef for SatClauses and SatLiterals, now there are CVC4 SatLiteral/SatClause types and mappings between them and the internal sat solver clause/literal representation
* added abstract classes for DPLLSatSolver and BVSatSolver different interfaces
Replaced TheoryBV with bitblasting implementation:
* all operators bitblasted
* only operator elimination rewrite rules so far
Dejan Jovanović [Fri, 24 Feb 2012 20:29:12 +0000 (20:29 +0000)]
Theory interface changes:
solve -> ppAsert
staticLearning -> ppStaticLearn
preprocess -> ppRewrite
SolveStatus -> PPAssertStatus (SOLVE_* -> PP_ASSERT_*)
via Eclipse refactoring magic.
Morgan Deters [Thu, 23 Feb 2012 23:08:03 +0000 (23:08 +0000)]
Added ability to set a "cvc4-specific logic" in standards-compliant
SMT-LIBv1 and SMT-LIBv2 input:
In SMT-LIBv1, you specify the "cvc4_logic" benchmark attribute; for instance:
(benchmark actually_a_sat_benchmark_but_looks_like_uf
:logic QF_UF
:cvc4_logic { QF_SAT }
[...]
In SMT-LIBv2, you use a set-info; for instance:
(set-logic QF_UF)
(set-info :cvc4-logic "QF_SAT")
[...]
Right now, the only thing this does is disable the symmetry breaker for
benchmarks like the above ones.
As part of this work, TheoryEngine::setLogic() was removed (the logic field there
wasn't actually used anywhere, its need disappeared when
Theory::setUninterpretedSortOwner() was provided).
Also, Theory::d_uninterpretedSortOwner got a name change to
Theory::s_uninterpretedSortOwner, to highlight that it is static to the Theory
class. This represents a breakage of our separation goals for CVC4, since it
means that two SmtEngines cannot be created separately to solve a QF_AX and
QF_UF problem. A bug report is pending.
Morgan Deters [Thu, 23 Feb 2012 22:02:45 +0000 (22:02 +0000)]
pcvc4 only built if --with-portfolio given to the configure script (Clark-requested change)
Tim King [Wed, 22 Feb 2012 22:32:45 +0000 (22:32 +0000)]
Fix for bug 305.
Morgan Deters [Wed, 22 Feb 2012 22:24:19 +0000 (22:24 +0000)]
fixes to configure and boost.m4 to make certain boost installations nonfatal errors; threading support should only be required to build pcvc4, not cvc4
Morgan Deters [Wed, 22 Feb 2012 20:36:15 +0000 (20:36 +0000)]
another static library unavailability issue
Morgan Deters [Wed, 22 Feb 2012 20:12:44 +0000 (20:12 +0000)]
make sure to clear out READLINE_LIBS if readline causes problems at configure time; fixes a bug reported by Clark for static-binary builds on machines where no static libreadline is available (like CIMS machines)
Morgan Deters [Wed, 22 Feb 2012 20:08:57 +0000 (20:08 +0000)]
Added OutputChannel::propagateAsDecision() functionality, allowing a theory
to request a decision on a literal. All these theory requests are kept in a
context-dependent queue and serviced in order when the SAT solver goes to make a
decision. Requests that don't have a SAT literal give an assert-fail. Requests
for literals that already have an assignment are silently ignored.
Since the queue is CD, requests can actually be serviced more than once (e.g., if
a request is made at DL 5, but not serviced until DL 10, and later, a conflict
backtracks to level 7, the request may be serviced again).
Performance impact: none to negligible for theories that don't use it
See http://church.cims.nyu.edu/regress-results/compare_jobs.php?job_id=3620&reference_id=3614&mode=&category=&p=0
Morgan Deters [Wed, 22 Feb 2012 15:30:51 +0000 (15:30 +0000)]
Fixes to documentation / fixes for MacOS
Kshitij Bansal [Wed, 22 Feb 2012 03:00:24 +0000 (03:00 +0000)]
minor change to order fn in sat solver's ElimLt
(better, (marginally) faster -- regressions 3605, 3606)
Morgan Deters [Tue, 21 Feb 2012 23:02:23 +0000 (23:02 +0000)]
add a "--with-portfolio" configure option that makes a missing boost-thread library an error; useful for builds requiring a "pcvc4" binary at the end
Morgan Deters [Tue, 21 Feb 2012 22:13:05 +0000 (22:13 +0000)]
fix src/util/hash.h to specialize GNU's hash template for <uint64_t> on platforms that need it; fixes Mac builds.
Morgan Deters [Tue, 21 Feb 2012 21:52:17 +0000 (21:52 +0000)]
language bindings fixes for yesterday's portfolio merge
Dejan Jovanović [Tue, 21 Feb 2012 19:43:46 +0000 (19:43 +0000)]
Fix for bug303. The problem was with function applications that get normalized when added to the term database. For example, if x=y exists, and the term f(x) is added, f(y) was stored. So, when getExplanation(f(x), f(y)) was called, trouble ensued. I now keep the original version so that explanations can be properly produced.
Also added theory::assertions debug flag that will printout assertions of each theory for ease and uniformity of debugging in the future.
Morgan Deters [Tue, 21 Feb 2012 19:24:51 +0000 (19:24 +0000)]
don't require libboost_thread (its presence is detected at configure-time), and other build/documentation fixes from yesterday's portfolio merge; resolves bug 302
Morgan Deters [Mon, 20 Feb 2012 20:04:31 +0000 (20:04 +0000)]
fix sharing issue for portfolio (full lit-to-node map wasn't being kept in my previous checkin)
Morgan Deters [Mon, 20 Feb 2012 18:23:15 +0000 (18:23 +0000)]
fix "make dist"
Morgan Deters [Mon, 20 Feb 2012 18:22:27 +0000 (18:22 +0000)]
zlib not required; remove configure's dependency on it
Morgan Deters [Mon, 20 Feb 2012 17:59:33 +0000 (17:59 +0000)]
portfolio merge
Morgan Deters [Mon, 20 Feb 2012 16:28:44 +0000 (16:28 +0000)]
readline links in -ltermcap -ltinfo too (fixes breakage in static-binary builds)
Morgan Deters [Mon, 20 Feb 2012 14:48:22 +0000 (14:48 +0000)]
Added Theory::postsolve() infrastructure as Clark requested.
(Though currently unused.)
For theories that request presolve and postsolve (in their kinds file),
they will get a presolve() notification before the first check(). After
the final check during the current search, they get a postsolve().
presolve() and postsolve() notifications always come in pairs, bracketing
all check()/propagate()/getValue() calls related to a single query. In
the case of incremental benchmarks, theories may get additional
presolve()/postsolve() pairs, but again, they always come in pairs.
Expected performance impact: none (for theories that don't use it)
http://church.cims.nyu.edu/regress-results/compare_jobs.php?job_id=3598&reference_id=3581&p=5
Morgan Deters [Mon, 20 Feb 2012 13:44:50 +0000 (13:44 +0000)]
By default, ONLY enable symmetry breaker ONLY for QF_UF (both SMT-LIBv1
and SMT-LIBv2).
There are --enable-symmetry-breaker and --disable-symmetry-breaker
options that are always respected regardless of this default.
Expected performance impact: positive
New default (UF only) compared to old default (always on):
http://church.cims.nyu.edu/regress-results/compare_jobs.php?job_id=3594&reference_id=3595&p=5
Symmetry breaker remains a big win on UF:
http://church.cims.nyu.edu/regress-results/compare_jobs.php?job_id=3594&reference_id=3596&p=5
The last link to results looks at first that the symmetry breaker should
always be turned off, since its use loses more regressions than it gains.
*However*, the lost ones are only our "QF_SAT" benchmarks. For these, we
should indeed turn off the symmetry breaker, but that's impossible for
now because we tag them internally with the logic "QF_UF."
Morgan Deters [Thu, 16 Feb 2012 13:30:28 +0000 (13:30 +0000)]
clarify wording in README, thanks for finding this Francois!
Tim King [Thu, 16 Feb 2012 00:54:12 +0000 (00:54 +0000)]
Last commit accidentally lacked r2778 and r2779 from integer2. I have manually brought these changes over. Changed the tests used by test/regress/regress0/arith/integers/Makefile.am to be 15 of the more interesting tests. Did a bit of cleanup on TheoryArith to eliminate a warning and remove dead code.
Tim King [Wed, 15 Feb 2012 21:52:16 +0000 (21:52 +0000)]
This commit merges into trunk the branch branches/arithmetic/integers2 from r2650 to r2779.
- This excludes revision 2777. This revision had some strange performance implications and was delaying the merge.
- This includes the new DioSolver. The DioSolver can discover conflicts, produce substitutions, and produce cuts.
- The DioSolver can be disabled at command line using --disable-dio-solver.
- This includes a number of changes to the arithmetic normal form.
- The Integer class features a number of new number theoretic function.
- This commit includes a few rather loud warning. I will do my best to take care of them today.
François Bobot [Mon, 13 Feb 2012 23:12:15 +0000 (23:12 +0000)]
precision in theoryskel
Morgan Deters [Mon, 13 Feb 2012 01:06:01 +0000 (01:06 +0000)]
proper handling of improper get-value
Morgan Deters [Sun, 12 Feb 2012 22:01:47 +0000 (22:01 +0000)]
copyright year updated to 2012
Morgan Deters [Sun, 12 Feb 2012 20:59:13 +0000 (20:59 +0000)]
separate new-theory components into a "theoryskel" directory so that new files can be added to it without modifying the script.
Morgan Deters [Sat, 11 Feb 2012 21:57:14 +0000 (21:57 +0000)]
ensure using bash for new-theory script
Morgan Deters [Fri, 10 Feb 2012 23:43:06 +0000 (23:43 +0000)]
attempt at a fix for the local regression failure (CLN linking issues on oneiric
Morgan Deters [Fri, 10 Feb 2012 23:36:07 +0000 (23:36 +0000)]
script to ease creating a new theory from scratch (will go along with new reference documentation)
Morgan Deters [Fri, 10 Feb 2012 20:27:10 +0000 (20:27 +0000)]
correct comment typo found during today's architectural meeting
Dejan Jovanović [Thu, 9 Feb 2012 21:25:00 +0000 (21:25 +0000)]
fixing antoher small bug in backtracking
Dejan Jovanović [Wed, 8 Feb 2012 16:04:24 +0000 (16:04 +0000)]
fixing a bug in uf_engine application lookup backtracking
this should also fix bug299
Tim King [Wed, 8 Feb 2012 00:31:00 +0000 (00:31 +0000)]
Number of changes to cvc_printer.cpp. Specialized the printing for BVPLUS, BVSUB, and BVMULT. Fixed a bug in printing on PREFIX operators. Added parenthsis for POSTFIX operators. Passing the ouroborous test now.
Morgan Deters [Tue, 7 Feb 2012 22:13:12 +0000 (22:13 +0000)]
re-adding comment about available languages
Dejan Jovanović [Tue, 7 Feb 2012 16:20:52 +0000 (16:20 +0000)]
removing the 100 integer benchmarks from regress0, too many
Dejan Jovanović [Tue, 7 Feb 2012 16:14:17 +0000 (16:14 +0000)]
fixing some missing stuff
Tim King [Mon, 6 Feb 2012 18:32:52 +0000 (18:32 +0000)]
Fixing a bug in the integer unit tests when configured for GMP with assertions off.
Dejan Jovanović [Sun, 5 Feb 2012 21:44:02 +0000 (21:44 +0000)]
changes to the cvc4 language printer, so that it actually prints the cvc4 language
all theory writers should take a look a what's being printed, to ensure all cases are covered
Andrew Reynolds [Sat, 4 Feb 2012 22:19:12 +0000 (22:19 +0000)]
support for isWellFounded/mkGroundTerm on uninterpretted sorts. cvc4 now assumes uninterpretted sorts are well-founded, allowing datatypes to work with uninterpretted sort subdata
Dejan Jovanović [Fri, 3 Feb 2012 23:17:30 +0000 (23:17 +0000)]
updating configure to use python-config for building python bindings
Morgan Deters [Fri, 27 Jan 2012 20:00:54 +0000 (20:00 +0000)]
effecting the same change in the compat Java binding as was done to CVC3 yesterday (ValidityChecker::value() and ValidityChecker::getValue())
Tim King [Wed, 25 Jan 2012 16:36:19 +0000 (16:36 +0000)]
Adding regress1 test ooo.rf6.smt2.
Tim King [Mon, 23 Jan 2012 21:13:08 +0000 (21:13 +0000)]
Partial fix to TheoryEngine::getExplanation so that SharedAssertions request explanations from the theory that can explain them. This partially fixes bug 295.
Dejan Jovanović [Mon, 23 Jan 2012 04:19:38 +0000 (04:19 +0000)]
fix for bug295
Andrew Reynolds [Tue, 17 Jan 2012 18:15:03 +0000 (18:15 +0000)]
updates to smt2 parser to support datatypes, minor updates to datatypes theory/rewriter to support datatypes with non-datatype subdata
Tim King [Thu, 15 Dec 2011 22:23:25 +0000 (22:23 +0000)]
Partial fix to bug 295.
Tim King [Thu, 15 Dec 2011 21:02:33 +0000 (21:02 +0000)]
Fix to the previous commit.
Tim King [Thu, 15 Dec 2011 20:39:20 +0000 (20:39 +0000)]
Partial fix in arithmetic for propagating shared terms. This partially resolves bug 289. Adds failing tests to regress1.
Andrew Reynolds [Wed, 14 Dec 2011 23:40:44 +0000 (23:40 +0000)]
added minor documentation for parametric datatypes, for bug 283
Morgan Deters [Wed, 14 Dec 2011 22:44:58 +0000 (22:44 +0000)]
minor fixes to printing and parsing of CVC-language defined functions and lambdas; resolves bug 294
Dejan Jovanović [Wed, 14 Dec 2011 09:31:21 +0000 (09:31 +0000)]
some more bug fixes (TNode -> Node, normalize literals in explanations)
Dejan Jovanović [Mon, 12 Dec 2011 09:47:37 +0000 (09:47 +0000)]
* merging some uf stuff from incremental_work branch that somehow nobody merged-in
* since two theories can propagate the same literal minisat now explicitly checks that a propagated literal has not been asserted yet
Dejan Jovanović [Sat, 10 Dec 2011 08:34:41 +0000 (08:34 +0000)]
adding additional checks for theories propagating literals that already have a value