2021-09-21  Steven Eker  <eker@pup>

	* ACU_ExtensionInfo.cc (ACU_ExtensionInfo::copy): take const arg

	* ACU_ExtensionInfo.hh (class ACU_ExtensionInfo): updated decl for copy()

===================================Maude137===========================================

2021-06-02  Steven Eker  <eker2@eker10>

	* ACU_UnificationSubproblem2.cc
	(ACU_UnificationSubproblem2::solve): added comment to explain why
	we need a separate branch for the identity case

2021-05-11  Steven Eker  <eker2@eker10>

	* ACU_Subproblem.cc (ACU_Subproblem::ACU_Subproblem): deleted
	commented out print statement
	(ACU_Symbol::~ACU_Subproblem): deleted commented out print
	statement

	* ACU_Symbol.cc (ACU_Symbol::normalize): undid previous
	range-based for loop because iterators aren't safe here due to
	garbage collector
	(ACU_Symbol::copyReduceSubtermsAndNormalize): ditto
	(ACU_Symbol::reduceArgumentsAndNormalize): ditto
	(ACU_Symbol::eqRewrite): ditto
	(ACU_Symbol::memoStrategy): ditto

2021-04-14  Steven Eker  <eker2@eker10>

	* ACU_TreeMatcher.cc (ACU_LhsAutomaton::eliminateBoundVariables):
	use range-based for loop
	(ACU_LhsAutomaton::eliminateGroundAliens): use range-based for
	loop
	(ACU_LhsAutomaton::eliminateGroundedOutAliens): use range-based
	for loop
	(ACU_LhsAutomaton::makeHighMultiplicityAssignment): use
	range-based for loop
	(ACU_LhsAutomaton::greedyPureMatch): use range-based for loop
	(ACU_LhsAutomaton::treeMatch): use range-based for loop (2 places)

	* ACU_Term.cc (ACU_Term::compileRhs2): use range-based for loop
	(ACU_Term::ACU_Term): pre-increment (three versions)
	(ACU_Term::deepSelfDestruct): use range-based for loop
	(ACU_Term::normalizeAliensAndFlatten): pre-increment; pre-decrement
	(ACU_Term::normalize): pre-increment; pre-decrement

	* ACU_UnificationSubproblem2.cc
	(ACU_UnificationSubproblem2::addUnification): use range-based for
	loop (3 places)
	(ACU_UnificationSubproblem2::unsolve): use range-based for loop
	(ACU_UnificationSubproblem2::buildAndSolveDiophantineSystem): use
	range-based for loop
	(ACU_UnificationSubproblem2::markReachableNodes): pre-increment
	(ACU_UnificationSubproblem2::addUnification): use range-based for
	loop to clear multiplicities
	(ACU_UnificationSubproblem2::unsolve): use range-based for loop to
	clear multiplicities
	(ACU_UnificationSubproblem2::computeLegalSelections): use
	range-based for loop (2 places)

2021-04-13  Steven Eker  <eker2@eker10>

	* ACU_Matcher.cc (ACU_LhsAutomaton::handleElementVariables):
	insert missing & in range-based for loop

	* ACU_Symbol.cc (ACU_Symbol::stackArguments): use range-based for
	loop
	(ACU_Symbol::termify): use range-based for loop
	(ACU_Symbol::computeGeneralizedSort): use range-based for loop
	(ACU_Symbol::computeGeneralizedSort2): use range-based for loop
	(ACU_Symbol::normalize): use range-based for loop
	(ACU_Symbol::copyReduceSubtermsAndNormalize): use range-based for
	loop
	(ACU_Symbol::makeDagNode): pre-increment (both versions)
	(ACU_Symbol::reduceArgumentsAndNormalize): use range-based for
	loop
	(ACU_Symbol::eqRewrite): use range-based for loop
	(ACU_Symbol::memoStrategy): use range-based for loop
	(ACU_Symbol::stackArguments): pre-decrement (2 places)
	(ACU_Symbol::makeCanonical): pre-increment
	(ACU_Symbol::makeCanonicalCopy): pre-increment
	(ACU_Symbol::makeDagNode): replace ACU_DagNode::Pair with ACU_Pair
	(2 places, both versions)
	(ACU_Symbol::termify): replace ACU_DagNode::Pair with ACU_Pair (2
	places)
	(ACU_Symbol::makeCanonicalCopy): replace ACU_DagNode::Pair with
	ACU_Pair

	* ACU_Subproblem.cc (ACU_Subproblem): use range-based for loop (2
	places)
	(ACU_Subproblem::solveVariables): use range-based for loop
	(ACU_Subproblem::solveVariables): pre-increment
	(ACU_Subproblem::noVariableCase): pre-increment (4 places)
	(ACU_Subproblem::extractDiophantineSystem): pre-increment (3
	places)
	(ACU_Subproblem::computeAssignment): pre-increment (2 places)
	(ACU_Subproblem::fillOutExtensionInfo): pre-increment

	* ACU_Matcher.cc (ACU_LhsAutomaton::eliminateGroundAliens): use
	range-based for loop
	(ACU_LhsAutomaton::eliminateGroundedOutAliens): use range-based
	for loop
	(ACU_LhsAutomaton::computeTotalMultiplicity): use range-based for
	loop
	(ACU_LhsAutomaton::match): use range-based for loop
	(ACU_LhsAutomaton::fullMatch): use range-based for loop (2 places)
	(ACU_LhsAutomaton::handleElementVariables): use range-based for
	loop

2021-04-12  Steven Eker  <eker2@eker10>

	* ACU_LazySubproblem.cc (~ACU_LazySubproblem): use range-based for
	loop

	* ACU_ExtensionInfo.cc (ACU_ExtensionInfo::buildMatchedPortion):
	use range-based for loop (3 places)
	(ACU_ExtensionInfo::buildUnmatchedPortion): use range-based for
	loop; rewrote excessively complicated first loop

	* ACU_DagNode.cc (ACU_DagNode::markArguments): use range-based for
	loop
	(ACU_DagNode::getHashValue): use range-based for loop
	(ACU_DagNode::clearCopyPointers2): use range-based for loop
	(ACU_DagNode::argVecComputeBaseSort): use range-based for loop
	(ACU_DagNode::computeBaseSortForGroundSubterms): use range-based
	for loop
	(ACU_DagNode::insertVariables2): use range-based for loop
	(ACU_DagNode::indexVariables2): use range-based for loop
	(ACU_DagNode::matchVariableWithExtension): post increment

===================================Maude136===========================================

2020-12-11  Steven Eker  <eker2@eker10>

	* ACU_DagNode.cc (ACU_DagNode::instantiate2): take and pass
	maintainInvariants arg; only normalize and compute sort for ground
	dag if true
	(ACU_DagNode::instantiate2): remove comment about computing sorts
	in the narrowing case since now maintainInvariants will be false
	(ACU_DagNode::instantiateWithCopies2): pass maintainInvariants =
	false to instantiate()

	* ACU_DagNode.hh (class ACU_DagNode): updated decl for
	instantiate2()

===================================Maude132===========================================

2020-06-18  Steven Eker  <eker2@eker10>

	* ACU_UnificationSubproblem2.cc
	(ACU_UnificationSubproblem2::buildSolution): turn cerr into
	DebugInfo()

2020-06-06  Steven Eker  <eker2@eker10>

	* ACU_UnificationSubproblem2.cc
	(ACU_UnificationSubproblem2::buildAndSolveDiophantineSystem):
	DebugAdvisory() -> DebugInfo()

2020-06-05  Steven Eker  <eker2@eker10>

	* ACU_UnificationSubproblem2.cc
	(ACU_UnificationSubproblem2::buildSolution): don't
	computeBaseSortForGroundSubterms for identity here

	* ACU_Symbol.cc (ACU_Symbol::makeUnificationSubproblem): call
	computeBaseSortForGroundSubterms for identity here

	* ACU_UnificationSubproblem2.hh (class
	ACU_UnificationSubproblem2): added decl for reuseVariable()

	* ACU_UnificationSubproblem2.cc
	(ACU_UnificationSubproblem2::setMultiplicity): replace variables
	bound to aliens by their bindings
	(ACU_UnificationSubproblem2::setMultiplicity): unmade above change
	and added detail comment with example to explain why eager
	replacement fails
	(ACU_UnificationSubproblem2::reuseVariable): added
	(ACU_UnificationSubproblem2::buildSolution): added optional code
	to use reuseVariable() optimization

2020-06-02  Steven Eker  <eker2@eker10>

	* ACU_DagNode.cc (ACU_DagNode::computeSolvedForm2): added DebugEnter()

2020-05-27  Steven Eker  <eker2@eker10>

	* ACU_UnificationSubproblem2.cc
	(ACU_UnificationSubproblem2::solve): added DebugInfo()s for branch
	on hasUnequalLeftIdentityCollapse()

===================================Maude128a===========================================

2019-12-03  Steven Eker  <eker@mu>

	* ACU_BaseDagNode.cc (getSize): use safeCastNonNull<>() (2 places)

===================================Maude127===========================================

2019-11-11  Steven Eker  <eker@mu>

	* ACU_DagNode.cc (computeBaseSortForGroundSubterms): no early termination
	in UNIMPLEMENTED case

	* ACU_UnificationSubproblem2.cc (buildSolution): pass false to
	warnAboutUnimplemented arg

	* ACU_DagNode.hh (ACU_BaseDagNode): updated decl for
	computeBaseSortForGroundSubterms()

	* ACU_DagNode.cc (computeBaseSortForGroundSubterms): take and pass
	warnAboutUnimplemented flag; simplified

===================================Maude125===========================================

2019-07-24  Steven Eker  <eker@mu>

	* ACU_Term.cc (compareArguments): added comment about static analyzer
	warning

	* ACU_DagNode.cc (compareArguments): added comment about static analyzer
	warning

===================================Maude123===========================================

2019-05-23  Steven Eker  <eker@mu.csl.sri.com>

	* ACU_UnificationSubproblem2.cc (buildSolution): fix compiler warnings

===================================Maude121===========================================

2018-10-23  Steven Eker  <eker@install.csl.sri.com>

	* ACU_Symbol.hh (AssociativeSymbol): added decl for
	stackPhysicalArguments()

	* ACU_Symbol.cc (stackPhysicalArguments): added

2018-10-18  Steven Eker  <eker@install.csl.sri.com>

	* ACU_DagNode.cc (copyWithReplacement): added Assert() on
	argIndex

===================================Maude119===========================================

2017-04-20  Steven Eker  <eker@install.csl.sri.com>

	* ACU_Matcher.cc (buildBipartiteGraph): fixed symmetric bug
	(eliminateGroundedOutAliens): fixed symmetric bug
	(aliensOnlyMatch): fixed symmetric bug

	* ACU_GreedyMatcher.cc (greedyMatch): fixed symmetric bug

	* ACU_NGA_LhsAutomaton.cc (match): fixed two symmetric bugs

	* ACU_TreeMatcher.cc (eliminateGroundedOutAliens): fixed bug where we had
	the test for going past the last potential match the wrong way around
	(greedyMatch): fixed symmetric bug

	* ACU_DagOperations.cc (findFirstPotentialMatch): added comments

	* ACU_LazySubproblem.cc (solve): fix bug where we had the test for going
	pass last potential match the wrong way around

2017-04-19  Steven Eker  <eker@install.csl.sri.com>

	* ACU_LazySubproblem.cc (solve): added comments; end search early, as soon
	as stripperTerm is definitely greater than subject on current path

	* ACU_TreeMatcher.cc (treeMatch): added comment
	(treeMatch): changed comments "could be smarter" to explanations
	of why it's not worth being smarter (3 places)

	* ACU_CollectorLhsAutomaton.cc (collect): added comments

2017-04-17  Steven Eker  <eker@install.csl.sri.com>

	* ACU_LhsCompiler0.cc (tryToMakeCollectorLhsAutomaton): added support
	for ACU_BndVarLhsAutomaton

	* ACU_DagNode.hh (ACU_BaseDagNode): added friend class
	ACU_BndVarLhsAutomaton

	* ACU_Theory.hh: added class ACU_BndVarLhsAutomaton

	* ACU_BndVarLhsAutomaton.cc: created

	* ACU_BndVarLhsAutomaton.hh: created

2017-04-14  Steven Eker  <eker@install.csl.sri.com>

	* ACU_VarLhsAutomaton.cc (match): updated comments

===================================Maude112a===========================================

2017-02-23  Steven Eker  <eker@install.csl.sri.com>

	* ACU_DagNode.cc (instantiateWithCopies2): ifdef'd out normal form, sort and
	ground flag computation and added comment to explain why

2017-02-21  Steven Eker  <eker@install.csl.sri.com>

	* ACU_DagNode.hh (ACU_BaseDagNode): updated decl for
	instantiateWithReplacement()

	* ACU_DagNode.cc (instantiateWithReplacement): handle lazy contexts

2017-02-17  Steven Eker  <eker@install.csl.sri.com>

	* ACU_TreeDagNode.hh (ACU_BaseDagNode): deleted decl for stackArguments()

	* ACU_TreeDagNode.cc (stackArguments): deleted

	* ACU_DagNode.cc (stackArguments): deleted

	* ACU_DagNode.hh (ACU_BaseDagNode): deleted decl for stackArguments()

	* ACU_Symbol.hh (AssociativeSymbol): updated decl for stackArguments()

	* ACU_Symbol.cc (stackArguments): handle respectFrozen and
	eagerContext arguments

===================================Maude111b===========================================

2016-12-20  Steven Eker  <eker@install.csl.sri.com>

	* ACU_TreeDagNode.cc (copyAll2): added missing return statement

2016-11-10  Steven Eker  <eker@install.csl.sri.com>

	* ACU_TreeDagNode.hh (ACU_BaseDagNode): added decl for copyAll2()

	* ACU_TreeDagNode.cc (copyAll2): added

	* ACU_DagNode.hh (ACU_BaseDagNode): added decl for copyAll2()

	* ACU_DagNode.cc (copyAll2): added

===================================Maude111===========================================

2016-05-18  Steven Eker  <eker@install.csl.sri.com>

	* ACU_UnificationSubproblem2.cc (addUnification): check for subtermIndex
	!= NONE
	(setMultiplicity): check for variable bound to identity; this fixes
	a bug introduced in Maude108 where classify assumes such things
	have already canceled

===================================Maude110===========================================

2016-05-17  Steven Eker  <eker@install.csl.sri.com>

	* ACU_Symbol.cc (computeGeneralizedSort2): fixed nasty FMR bug
	where we were appending a reference to the same Vector which
	became stale if the append forced reallocation

2016-03-24  Steven Eker  <eker@install.csl.sri.com>

	* ACU_Symbol.cc (computeGeneralizedSort2): rewritten

2016-03-18  Steven Eker  <eker@install.csl.sri.com>

	* ACU_Symbol.cc (computeGeneralizedSort2): added

===================================Maude109===========================================

2015-08-07  Steven Eker  <eker@ape.csl.sri.com>

	* ACU_Symbol.cc (unificationPriority): make ACU have a lower
	priority than AC

2015-07-31  Steven Eker  <eker@ape.csl.sri.com>

	* ACU_UnificationSubproblem2.cc (classify): handle ground aliens
	specially

2015-07-30  Steven Eker  <eker@ape.csl.sri.com>

	* ACU_DagNode.cc (computeBaseSortForGroundSubterms): call
	setGround() in the ground case

===================================Maude108===========================================

2014-06-20  Steven Eker  <eker@ape.csl.sri.com>

	* ACU_UnificationSubproblem2.cc (solve): added comment with new
	insight into why solved forms must be unsolved

===================================Maude104===========================================

2013-02-28  Steven Eker  <eker@ape.csl.sri.com>

	* ACU_UnificationSubproblem2.cc (addUnification): call killCancelledSubterms()

	* ACU_UnificationSubproblem2.hh (SimpleRootContainer): added decl
	for killCancelledSubterms()

	* ACU_UnificationSubproblem2.cc (killCancelledSubterms): added

2013-02-27  Steven Eker  <eker@ape.csl.sri.com>

	* ACU_UnificationSubproblem2.cc (ACU_UnificationSubproblem2):
	removed pointless #ifndef
	(addUnification): code cleaning
	(markReachableNodes): code cleaning
	(solve): fix performance bug where we were checking subterms
	rather than unifications for emptiness to detect the degenerate
	case
	(markReachableNodes): protect preSolveSubstitution rather than
	savedSubstitution since it will have a superset of bindings

2013-02-07  Steven Eker  <eker@ape.csl.sri.com>

	* ACU_UnificationSubproblem2.cc: only bind variables to dags which
	are in our theory - leave everything else to
	computeSolvedForm() - This is to fix a bug where we bind a variable
	to itself, or form an occurs check problem in an alien theory

===================================Maude96c===========================================

2012-07-10  Steven Eker  <eker@ape.csl.sri.com>

	* ACU_BaseDagNode.hh (DagNode): update comment on ASSIGNMENT now
	that we can have variables at the kind level, and thus we don't
	guarentee non-error sort this NormalizationStatus

===================================Maude96a===========================================

2012-04-30  Steven Eker  <eker@ape.csl.sri.com>

	* ACU_Term.cc (ACU_Term): multiplicities version: fix Assert(),
	now that we can have a single argument with multiplicity >= 2

2012-04-13  Steven Eker  <eker@ape.csl.sri.com>

	* ACU_DagNode.hh (ACU_BaseDagNode): updated decl for
	instantiateWithReplacement(); added decl for
	instantiateWithCopies2()

	* ACU_DagNode.cc (instantiateWithReplacement): rewritten to
	respect eager positions
	(instantiateWithCopies2): added

2012-03-30  Steven Eker  <eker@ape.csl.sri.com>

	* ACU_Symbol.cc (termify): code cleaning

2012-03-29  Steven Eker  <eker@ape.csl.sri.com>

	* ACU_Symbol.hh (AssociativeSymbol): added decl for termify()

	* ACU_Term.hh (Term): added decl for new ctor

	* ACU_Term.cc (ACU_Term): added version that takes multiplicities

	* ACU_Symbol.cc (termify): added

===================================Maude96===========================================

2011-11-22  Steven Eker  <eker@rho>

	* ACU_UnificationSubproblem2.cc (ACU_UnificationSubproblem2::solve): use restoreFromClone()
	to make sure that sort and dagnode information for variable created on the branch we are
	backtracking get purged from our UnificationContext object (4 places)

===================================Maude95c===========================================

2010-12-09  Steven Eker  <eker@rho>

	* ACU_Symbol.cc (ACU_Symbol::postOpDeclarationPass): don't call
	rightIdentitySortCheck() since we are commutative

===================================Maude95b===========================================

2010-10-19  Steven Eker  <eker@rho>

	* ACU_Symbol.cc (ACU_Symbol::makeCanonicalCopyEagerUptoReduced):
	becomes makeCanonicalCopy()

	* ACU_Symbol.hh (class ACU_Symbol):
	makeCanonicalCopyEagerUptoReduced() -> makeCanonicalCopy()

===================================Maude95a===========================================

2010-09-29  Steven Eker  <eker@rho>

	* ACU_Symbol.cc (ACU_Symbol::makeCanonicalCopyEagerUptoReduced):
	simplifed now that we only get unreduced nodes; use
	getCanonicalCopyEagerUptoReduced(); fix bug where we were not
	copying flags and sort

	* ACU_Symbol.hh (class ACU_Symbol): added decl for
	makeCanonicalCopyEagerUptoReduced()

	* ACU_Symbol.cc (ACU_Symbol::makeCanonicalCopyEagerUptoReduced):
	added
	(ACU_Symbol::makeCanonical): removed commment out tree->array
	conversion

2010-09-23  Steven Eker  <eker@rho>

	* ACU_LazySubproblem.cc (ACU_LazySubproblem::bindCollector): fix
	bug where we weren't handling the case where our collector
	variable had become bound by our stripper automaton

	* ACU_LhsAutomaton.cc (ACU_LhsAutomaton::complete): fixed out of
	date comment

2010-09-10  Steven Eker  <eker@rho>

	* ACU_UnificationSubproblem2.cc
	(ACU_UnificationSubproblem2::solve): don't exclude the null
	solution in the unequal identity collapse case

2010-09-09  Steven Eker  <eker@rho>

	* ACU_UnificationSubproblem2.cc
	(ACU_UnificationSubproblem2::solve): check
	hasUnequalLeftIdentityCollapse() and force generation of
	non-maximal solutions when it is true

2010-08-18  Steven Eker  <eker@rho>

	* ACU_UnificationSubproblem2.cc
	(ACU_UnificationSubproblem2::nextSelectionWithIdentity): deleted
	commented out old verions

	* ACU_DagNode.cc (ACU_DagNode::nonVariableSize): deleted

	* ACU_DagNode.hh (class ACU_DagNode): deleted decl for
	nonVariableSize()

===================================Maude95===========================================

2010-08-11  Steven Eker  <eker@rho>

	* ACU_DagNode.cc (ACU_DagNode::computeSolvedForm2): handle
	unification agaist bound variable by unifying against variables
	binding to avoid nontermination

2010-08-04  Steven Eker  <eker@rho>

	* ACU_UnificationSubproblem2.cc
	(ACU_UnificationSubproblem2::buildSolution): handle <oldvar> =? d
	the old way when the representative variable of <oldvar> is bound
	to avoid generating problems of the same size as we solve
	(ACU_UnificationSubproblem2::addUnification): handle variable rhs
	even when we don't have an identity

2010-08-03  Steven Eker  <eker@rho>

	* ACU_DagNode.cc (ACU_DagNode::computeSolvedForm2): rewritten to
	push problems of the form f(...) = X on the pending stack rather
	than pass them to VariableDagNode::computeSolvedForm2()

	* ACU_UnificationSubproblem2.hh (class
	ACU_UnificationSubproblem2): updated decl for addUnification()

	* ACU_UnificationSubproblem2.cc
	(ACU_UnificationSubproblem2::addUnification): handle marked
	argument

2010-07-29  Steven Eker  <eker@rho>

	* ACU_UnificationSubproblem2.hh (class
	ACU_UnificationSubproblem2): updated decl for classify();
	deleleted decl for isRestrictedSubterm(); updated decl for
	unsolve(); updated decl for setMultiplicity()
	(class ACU_UnificationSubproblem2): deleted data member
	restrictedSubterms; added data member markedSubterms

	* ACU_UnificationSubproblem2.cc
	(ACU_UnificationSubproblem2::addUnification): take solution as
	argument
	(ACU_UnificationSubproblem2::addUnification): simplified; keep set
	of indices for marked subterms
	(ACU_UnificationSubproblem2::setMultiplicity): use representative
	variable in a chain; return subterm index
	(ACU_UnificationSubproblem2::unsolve): simplified; never fail - we
	let Diophantine solver worry about pathological X = f(..., X,...)
	case
	(ACU_UnificationSubproblem2::solve): simplified using new
	unsolve() symantics
	(ACU_UnificationSubproblem2::classify): simplified - no longer
	chase variable chains as we should only have representative
	variables in our system
	(ACU_UnificationSubproblem2::isRestrictedSubterm): deleted

	* ACU_UnificationSubproblem2.hh (class
	ACU_UnificationSubproblem2): updated decl for addUnification()

2010-07-21  Steven Eker  <eker@rho>

	* ACU_UnificationSubproblem2.cc
	(ACU_UnificationSubproblem2::buildAndSolveDiophantineSystem):
	comment out the case where with fail because we only have one
	Diophantine variable since even with no basis elements we can
	still get a unifier

2010-07-20  Steven Eker  <eker@rho>

	* ACU_UnificationSubproblem2.hh (class
	ACU_UnificationSubproblem2): added decl for isRestrictedSubterm

	* ACU_UnificationSubproblem2.cc
	(ACU_UnificationSubproblem2::classify): use equal() rather than ==
	for checking for restricted subterms
	(ACU_UnificationSubproblem2::isRestrictedSubterm): added
	(ACU_UnificationSubproblem2::classify): rewritten using
	isRestrictedSubterm() to ensure that variables can be restricted

2010-07-19  Steven Eker  <eker@rho>

	* ACU_UnificationSubproblem2.cc
	(ACU_UnificationSubproblem2::markReachableNodes): fix bug where we
	were deleting maximalSelections here rather than in
	~ACU_UnificationSubproblem2()

2010-07-09  Steven Eker  <eker@rho>

	* ACU_UnificationSubproblem2.cc
	(ACU_UnificationSubproblem2::buildSolution): add an Assert to
	detect trivial bounds violation
	(ACU_UnificationSubproblem2::computeLegalSelections): use index
	member of basis element rather than separately maintained index
	which is incorrect

2010-07-08  Steven Eker  <eker@rho>

	* ACU_UnificationSubproblem2.cc
	(ACU_UnificationSubproblem2::solve): set maximalSelections
	(ACU_UnificationSubproblem2::ACU_UnificationSubproblem2): clear
	maximalSelections

	* ACU_UnificationSubproblem2.hh (class
	ACU_UnificationSubproblem2): added data member maximalSelections

	* ACU_UnificationSubproblem2.cc
	(ACU_UnificationSubproblem2::addUnification): use hasIdentity()
	(ACU_UnificationSubproblem2::unsolve): use hasIdentity()
	(ACU_UnificationSubproblem2::solve): use hasIdentity()

	* ACU_DagNode.cc (ACU_DagNode::computeBaseSortForGroundSubterms):
	removed commented out code

2010-07-07  Steven Eker  <eker@rho>

	* ACU_UnificationSubproblem2.hh (class
	ACU_UnificationSubproblem2): added decl for
	computeLegalSelections()

===================================Maude94a===========================================

2010-06-29  Steven Eker  <eker@rho>

	* ACU_Symbol.cc (ACU_Symbol::canResolveTheoryClash): added

	* ACU_DagNode.cc (ACU_DagNode::computeSolvedForm2): try using
	resolveTheoryClash()

2010-06-25  Steven Eker  <eker@rho>

	* ACU_UnificationSubproblem2.cc
	(ACU_UnificationSubproblem2::addUnification): handle the theory
	clash case where the rhs is actually our identity

	* ACU_DagNode.cc (ACU_DagNode::computeSolvedForm2): quick hack to
	handle theory clashes asymetrically

	* ACU_UnificationSubproblem2.hh (class
	ACU_UnificationSubproblem2): added data member restrictedSubterms

	* ACU_UnificationSubproblem2.cc
	(ACU_UnificationSubproblem2::unsolve): handle X = f(..., X, ...)
	case where collapse might be possible
	(ACU_UnificationSubproblem2::addUnification): rewritten to handle
	theory clash unifications
	(ACU_UnificationSubproblem2::classify): handle restricted subterms

2010-06-24  Steven Eker  <eker@rho>

	* ACU_UnificationSubproblem2.cc
	(ACU_UnificationSubproblem2::buildAndSolveDiophantineSystem):
	given each basis element a unique index

	* ACU_UnificationSubproblem2.hh (class
	ACU_UnificationSubproblem2): added index field to struct Entry

	* ACU_UnificationSubproblem2.cc
	(ACU_UnificationSubproblem2::nextSelectionWithIdentity): avoid
	generating subsets of previous selections

	* ACU_UnificationSubproblem2.hh (class
	ACU_UnificationSubproblem2): added data member old
	(class ACU_UnificationSubproblem2): added NatSetList typedef
	(class ACU_UnificationSubproblem2): added date member selectionSet

	* ACU_UnificationSubproblem2.cc
	(ACU_UnificationSubproblem2::buildAndSolveDiophantineSystem):
	change criteria for failing due to lack of coverage

	* ACU_UnificationSubproblem2.hh (class
	ACU_UnificationSubproblem2): added data member needToCover

	* ACU_UnificationSubproblem2.cc: fill out needToCover

	* ACU_UnificationSubproblem2.hh (class
	ACU_UnificationSubproblem2): added decl for
	nextSelectionWithIdentity()

	* ACU_UnificationSubproblem2.cc
	(ACU_UnificationSubproblem2::buildSolution): handle null
	assignments by using getIdentityDag()
	(ACU_UnificationSubproblem2::nextSelectionWithIdentity): added
	(ACU_UnificationSubproblem2::solve): use
	nextSelectionWithIdentity() in identity case

2010-06-23  Steven Eker  <eker@rho>

	* ACU_UnificationSubproblem2.hh (class
	ACU_UnificationSubproblem2): update decl for classify()

	* ACU_UnificationSubproblem2.cc
	(ACU_UnificationSubproblem2::classify): fixed bug where we were
	not checking for unbound variable
	(ACU_UnificationSubproblem2::classify): fixed bug where we assume
	we could treat our own top symbol as a stable symbol, even though
	in any combination of basis elements it could take multiple things
	and not be forced to unify against a single specific thing
	(ACU_UnificationSubproblem2::classify): pass canTakeIdentity flag
	rather than needToCover flag; fix bug where we could have left
	needToCover false even when there was no identity
	(ACU_UnificationSubproblem2::buildAndSolveDiophantineSystem): use
	new classify() semantics

2010-06-22  Steven Eker  <eker@rho>

	* ACU_UnificationSubproblem2.cc
	(ACU_UnificationSubproblem2::buildAndSolveDiophantineSystem):
	rewritten using classify() to fix bug in basis element killing
	code

	* ACU_UnificationSubproblem2.hh (class
	ACU_UnificationSubproblem2): added decl for classify()

	* ACU_UnificationSubproblem2.cc
	(ACU_UnificationSubproblem2::classify): added

2010-06-07  Steven Eker  <eker@rho>

	* ACU_UnificationSubproblem2.cc
	(ACU_UnificationSubproblem2::buildAndSolveDiophantineSystem):
	added code to exclude basis elements that force unresolvable
	theory clashes

2010-05-21  Steven Eker  <eker@rho>

	* ACU_DagNode.cc (ACU_DagNode::computeBaseSortForGroundSubterms):
	hack to allow unification to proceed on non-ground ACU dags

===================================Maude94===========================================

2010-04-16  Steven Eker  <eker@rho>

	* ACU_LhsCompiler1.cc (ACU_Term::analyseConstraintPropagation):
	code cleaning

2010-04-15  Steven Eker  <eker@rho>

	* ACU_LhsCompiler2.cc
	(ACU_Term::findConstraintPropagationSequence): minor code cleaning

2010-04-14  Steven Eker  <eker@rho>

	* ACU_LhsCompiler2.cc
	(ACU_Term::findConstraintPropagationSequence): amongst sequences
	that bind uniquely the same number of variables, perfer the longer
	sequence

	* ACU_Term.hh (class ACU_Term): deleted decl for
	addIndependentAliens()

	* ACU_LhsCompiler2.cc (ACU_Term::compileAliensOnlyCase): code
	cleaning
	(ACU_Term::findConstraintPropagationSequence): rewritten to avoid
	exponential blow up in more cases.
	(ACU_Term::findConstraintPropagationSequence): allow current
	forceable NGA to be pruned if we've already explored a path and
	there is nothing to be gained by matching it now
	(ACU_Term::compileAliensOnlyCase): don't call
	addIndependentAliens() since we assume best sequence will already
	contain all forceable NGAs
	(ACU_Term::addIndependentAliens): deleted

===================================Maude93a===========================================

2010-03-12  Steven Eker  <eker@rho>

	* ACU_RhsAutomaton.cc (ACU_RhsAutomaton::buildArguments): use
	nrArguments

	* ACU_Term.cc (ACU_Term::compileRhs2): rewritten to compile/build
	larger subterms first, to avoid quadratic conflict arcs on clt's
	example

	* ACU_RhsAutomaton.cc (ACU_RhsAutomaton::close): set nrArguments
	(ACU_RhsAutomaton::construct, ACU_RhsAutomaton::replace): use
	nrArguments rather than arguments.size() to avoid checking for a
	null Vector

	* ACU_RhsAutomaton.hh (class ACU_RhsAutomaton): added date element
	nrArguments

===================================Maude93===========================================

2010-02-26  Steven Eker  <eker@rho>

	* ACU_DagOperations.cc (ACU_DagNode::binarySearch): removed
	setOnLs()/setOnGeq() since it seems to be a pessimization (both
	versions)

2010-02-24  Steven Eker  <eker@rho>

	* ACU_Normalize.cc (ACU_DagNode::copyAndBinaryInsert): use new
	binarySearch() convention

2010-02-19  Steven Eker  <eker@rho>

	* ACU_DagNode.hh (class ACU_DagNode): updated decl for DagNode*
	version of binarySearch()

	* ACU_DagOperations.cc (ACU_DagNode::binarySearch): rewrote
	DagNode* version
	(ACU_DagNode::eliminateSubject): use new binarySearch() convention

	* ACU_DagNode.hh (class ACU_DagNode): updated decl for Term*
	version of binarySearch()

	* ACU_GndLhsAutomaton.cc (ACU_GndLhsAutomaton::match): use new
	binarySearch() convention

	* ACU_Matcher.cc (ACU_LhsAutomaton::eliminateGroundAliens): use
	new binarySearch() convention

	* ACU_DagOperations.cc (ACU_DagNode::binarySearch): rewritten to
	return position rather than pass it back through a reference argument
	(ACU_DagNode::eliminateArgument): use new binarySearch semantics

2010-02-18  Steven Eker  <eker@rho>

	* ACU_DagOperations.cc (ACU_DagNode::binarySearch): use unsigned
	sum optimization in both versions

2010-01-06  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_Term.cc (compileRhs2): experiment code to check my
	understanding of clt's extreme right nesting example

===================================Maude92c===========================================

2009-12-09  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_TreeDagNode.cc (makeCanonical): added

	* ACU_Symbol.cc (makeCanonical): use
	ACU_TreeDagNode::makeCanonical()

2009-12-03  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_Symbol.hh (class ACU_Symbol): added decl for makeCanonical()

	* ACU_TreeDagNode.hh (class ACU_TreeDagNode): make ACU_Symbol a
	friend

	* ACU_Symbol.cc (makeCanonical): added

===================================Maude92b===========================================

2008-12-22  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_Symbol.cc (computeGeneralizedSort): new getSortFunction()
	convention

2008-12-19  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_Subproblem.hh: derive from DelayedSubproblem

===================================Maude92===========================================

2008-09-24  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_Matcher.cc (fullMatch): fix bug where we weren't setting up
	the extensionInfo in the new fast success case

2008-09-23  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_Matcher.cc (fullMatch): catch the case where we have no
	patterns, one variable that can't take identity, one subject and
	extension
	(fullMatch): catch the same case where we can take identity but
	we're not allowed to since there were only two things in the
	subject

===================================Maude91c===========================================

2008-09-11  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_DagNode.cc (computeBaseSortForGroundSubterms): added default
	case to avoid compiler warning

2008-05-08  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_UnificationSubproblem2.cc (buildAndSolveDiophantineSystem):
	use IntSystem rather than MpzSystem
	(buildAndSolveDiophantineSystem): use new IntSystem semantics to
	avoid making a zero padded copy of each equation

===================================Maude91a===========================================

2008-04-18  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_Symbol.hh (class ACU_Symbol): added decl for unificationPriority()

	* ACU_Symbol.cc (unificationPriority): added

===================================Maude91===========================================

2008-03-23  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_DagNode.hh (class ACU_DagNode): ACU_UnificationSubproblem,
	ACU_UnificationWithExtensionSubproblem no longer friends

	* ACU_UnificationWithExtensionSubproblem.cc: deleted

	* ACU_UnificationWithExtensionSubproblem.hh: deleted

	* ACU_UnificationWithExtensionSubproblem.cc: deleted

	* ACU_UnificationWithExtensionSubproblem.hh: deleted

	* ACU_Theory.hh: removed classes ACU_UnificationSubproblem,
	ACU_UnificationWithUnificationSubproblem

	* ACU_DagNode.hh (class ACU_DagNode): deleted commented out decl
	for old version of computeSolvedForm2()

	* ACU_DagNode.cc (computeSolvedForm2): deleted commented out old
	version

===================================Maude90a===========================================

2008-02-08  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_UnificationSubproblem2.hh (class
	ACU_UnificationSubproblem2): added date member
	preSolveSubstitution; added decl for unsolve()

	* ACU_UnificationSubproblem2.cc (solve): unsolve solved forms in
	our theory
	(unsolve): added

	* ACU_DagNode.cc (computeSolvedForm2): Substitution ->
	UnificationContext

	* ACU_DagNode.hh (class ACU_DagNode): updated decl for
	computeSolvedForm2()

2008-02-05  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_Symbol.cc (makeUnificationSubproblem): added

	* ACU_Symbol.hh (class ACU_Symbol): added decl for
	makeUnificationSubproblem()

	* ACU_DagNode.hh (class ACU_DagNode): updated decl for computeSolvedForm2()

	* ACU_DagNode.cc (computeSolvedForm2): rewritten

2008-02-04  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_UnificationSubproblem2.cc: created

	* ACU_UnificationSubproblem2.hh: created

2008-01-17  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_UnificationSubproblem.cc (ACU_UnificationSubproblem):
	initialize savedSubstitution with 0 entries rather than with a
	single entry (that will end up being marked in GC)

===================================Maude90===========================================

2007-11-20  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_UnificationSubproblem.cc (ACU_UnificationSubproblem):
	savedSubstitution needs to be at least size 1 in new Substitution
	handling
	(unificationSolve): fix bug by using clone() to restore old
	substitution

2007-11-07  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_TreeDagNode.cc (indexVariables2): added

	* ACU_TreeDagNode.hh (class ACU_TreeDagNode): added decl for
	indexVariables2()

2007-11-05  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_DagNode.cc (indexVariables2, instantiateWithReplacement): added
	(instantiate2): use isGround() rather than checking for an unknown
	sort
	(instantiate2): call setGround()

	* ACU_DagNode.hh (class ACU_DagNode): added decl for
	indexVariables2() and instantiateWithReplacement() 

2007-11-01  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_DagNode.cc (instantiate2): updated

	* ACU_DagNode.hh (class ACU_DagNode): updated decl for
	instantiate2()

2007-09-28  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_UnificationSubproblem.cc (unificationSolve): replaced two
	clone() calls with copy() calls since when we copy back a saved
	substitution, both substitutions should have the same copy size

===================================Maude89h===========================================

2007-08-24  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_DagNode.cc (computeBaseSortForGroundSubterms): rewritten

	* ACU_DagNode.hh (class ACU_DagNode): updated decl for
	computeBaseSortForGroundSubterms()

	* ACU_UnificationSubproblem.cc (unificationSolve): added comments
	to indicate that fresh variables are deallocated when done with

2007-08-23  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_UnificationSubproblem.cc (buildSolution): use
	sortAndUniquize() in place of dumbNormalizeAtTop()

	* ACU_DagNode.cc (computeSolvedForm): becomes computeSolvedForm2()

	* ACU_DagNode.hh (class ACU_DagNode): computeSolvedForm() ->
	computeSolvedForm2()

2007-08-21  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_UnificationSubproblem.cc (initialize): simplify and comment
	(initialize): fix nasty bug by clearing previous selections

2007-08-17  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_UnificationSubproblem.hh (class ACU_UnificationSubproblem):
	update decl for addBasisElement()

	* ACU_UnificationSubproblem.cc (addBasisElement): pass element by
	reference; made assignment in if statement obvious

===================================Maude89g===========================================

2007-08-09  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_DagNode.hh (class ACU_DagNode): added decl for
	dumbNormalizeAtTop()

	* ACU_DagNode.cc (instantiate2): use dumbNormalizeAtTop() to avoid
	getting a tree form

	* ACU_UnificationSubproblem.cc (buildSolution): use
	dumbNormalizeAtTop() to avoid getting a tree form

	* ACU_Normalize.cc (dumbNormalizeAtTop): added
	(normalizeAtTop): use dumbNormalizeAtTop() for general case

	* ACU_UnificationSubproblem.cc (buildSolution): added Assert() to
	protect against getting a tree form from normalizeAtTop()

===================================Maude89f===========================================

2007-07-06  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_DagNode.cc (computeSolvedForm): use
	ACU_UnificationWithExtensionSubproblem()

	* ACU_Theory.hh: added ACU_UnificationWithUnificationSubproblem

2007-06-29  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_UnificationWithExtensionSubproblem.cc (generateUnificationSubproblem) 
	(fillOutExtensionInfo, nextSelection): added

2007-06-28  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_UnificationWithExtensionSubproblem.cc: created

	* ACU_UnificationWithExtensionSubproblem.hh: created

	* ACU_DagNode.hh (class ACU_DagNode): updated decl for
	computeSolvedForm()

	* ACU_DagNode.cc (computeSolvedForm): added extensionInfo arg

===================================Maude89c===========================================

2007-03-16  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_Symbol.cc (computeGeneralizedSort): reuse bddPair between
	iterations

2007-03-15  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_Symbol.cc (computeGeneralizedSort): pass realToBdd by ref

	* ACU_Symbol.hh (class ACU_Symbol): fix decl for
	computeGeneralizedSort()

===================================Maude89a===========================================

2007-03-14  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_UnificationSubproblem.hh (class ACU_UnificationSubproblem):
	added decl for markReachableNodes()

	* ACU_UnificationSubproblem.cc (markReachableNodes): added

	* ACU_UnificationSubproblem.hh (class ACU_UnificationSubproblem):
	derive from SimpleRootContainer

	* ACU_UnificationSubproblem.cc (ACU_UnificationSubproblem):
	initialize savedSubstitution
	(unificationSolve): don't call deallocateFreshVariables(); restore
	original substitution after we're done with selection

2007-03-13  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_Symbol.cc (computeGeneralizedSort): added

	* ACU_Symbol.hh (class ACU_Symbol): added decl for
	computeGeneralizedSort()

	* ACU_DagNode.hh (class ACU_DagNode): added decl for
	instantiate2()

	* ACU_DagNode.cc (instantiate2): added

	* ACU_UnificationSubproblem.cc (unificationSolve): keep a copy of
	the solution and restore is each time we give up on the current
	basis selection

	* ACU_UnificationSubproblem.hh (class ACU_UnificationSubproblem):
	added data member savedSubstitution

	* ACU_UnificationSubproblem.cc (buildSolution): added
	(unificationSolve): fix bug that we were clearing selection that
	we needed for backtracking

	* ACU_UnificationSubproblem.hh (class ACU_UnificationSubproblem):
	added decl for buildSolution()

	* ACU_DagNode.hh (class ACU_DagNode): ACU_UnificationSubproblem
	becomes a friend

	* ACU_Theory.hh: added class ACU_UnificationSubproblem

2007-03-12  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_DagNode.cc (computeSolvedForm): use coverable() check

	* ACU_UnificationSubproblem.cc (coverable): added

	* ACU_DagNode.cc (computeSolvedForm): use
	ACU_UnificationSubproblem

	* ACU_UnificationSubproblem.cc: created

	* ACU_UnificationSubproblem.hh: created

2007-03-09  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_DagNode.cc (computeBaseSortForGroundSubterms): added
	(computeSolvedForm): take car of upper bounds

	* ACU_DagNode.hh (class ACU_DagNode): added decl for
	computeBaseSortForGroundSubterms()

	* ACU_DagNode.cc (nonVariableSize): added
	(insertVariables2): added
	(computeSolvedForm): added stub

	* ACU_DagNode.hh (class ACU_DagNode): added decls for
	computeSolvedForm(), nonVariableSize(), insertVariables2()

===================================Maude89===========================================

2006-10-10  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_DagNode.hh: added declaration for getACU_DagNode() to
	appease gcc 4.1

===================================Maude88b===========================================

2005-10-06  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_Term.cc (deepCopy2): fix bug where we were testing s rather
	than s2 for 0

===================================Maude86c===========================================

2005-07-28  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_Term.hh (class ACU_Term): updated decl for SymbolMap*
	version of ctor

	* ACU_Term.cc (deepCopy2): handle translation to a non-ACU_Symbol
	(ACU_Term): force symbol arg to be a ACU_Symbol*

2005-07-01  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_Term.hh (class ACU_Term): updated decls for deepCopy2() and
	SymbolMap* version of ctor

	* ACU_Term.cc (deepCopy2): rewritten
	(ACU_Term): (SymbolMap* version) rewritten

===================================Maude86b===========================================

2003-08-28  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_Symbol.hh (class ACU_Symbol): added decl for
	rewriteAtTopNoOwise()

	* ACU_Symbol.cc (complexStrategy): rewritten to use
	rewriteAtTopNoOwise() for first 0 in semi-eager case
	(memoStrategy): ditto
	(rewriteAtTopNoOwise): added
	
===================================Maude82===========================================

2003-07-31  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_LazySubproblem.cc (bindCollector): fixed nasty bug where we
	were binding local rather than solution
	(solve): need to retract() after a successful assert() followed by
	subproblem failure (2 places)

===================================Maude81===========================================

2003-05-29  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_TreeMatcher.cc (treeMatch): added extra Assert()s for FULL case

	* ACU_LhsAutomaton.cc (addTopVariable): update nrExpectedUnboundVariables
	(ACU_LhsAutomaton): clear nrExpectedUnboundVariables
	(addTopVariable): fix bug where we were not checking that
	multiplicity == 1 in order to set collectorSeen

	* ACU_LhsAutomaton.hh (class ACU_LhsAutomaton): data member
	nrExpectedUnboundVariables

	* ACU_LhsAutomaton.cc (complete): fix bug where we weren't
	checking that single nga had multiplicity 1 before enabling
	treeMatchOK in FULL case

	* ACU_TreeMatcher.cc (treeMatch): check for only 1 thing left in
	FULL case

	* ACU_LazySubproblem.cc (ACU_LazySubproblem): call ctors for
	matchTime and local
	(bindCollector): use checkSort()
	(bindCollector): added Assert() for empty tree

	* ACU_LhsAutomaton.cc (complete): allow the use of tree matching
	in some FULL cases

	* ACU_LazySubproblem.cc (bindCollector): simplified as
	collectorSort will never be 0

	* ACU_TreeMatcher.cc (treeMatch): use ACU_LazySubproblem()

	* ACU_LazySubproblem.hh (class ACU_LazySubproblem): added decl for
	bindCollector()
	(class ACU_LazySubproblem): replaced topSymbol with subject;
	updated decls for bindCollector() and ctor

	* ACU_LazySubproblem.cc (ACU_LazySubproblem): init topSymbol

	* ACU_LazySubproblem.hh (class ACU_LazySubproblem): added data
	member topSymbol; updated decl for ctor

	* ACU_LazySubproblem.cc (ACU_LazySubproblem): remaining arg is now
	a const ACU_Tree&; use copy() to initialize matchTime
	(bindCollector): added

	* ACU_LazySubproblem.hh (class ACU_LazySubproblem): data member
	remaining becomes ACU_Tree; updated decl for ctor

2003-05-19  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_Normalize.cc (normalizeAtTop): use useTree()
	(insertAlien): use useTree()

	* ACU_Symbol.hh (class ACU_Symbol): updated decl for ACU_Symbol()
	(useTree): added

	* ACU_Symbol.cc (ACU_Symbol): initialize useTreeFlag

	* ACU_Symbol.hh (class ACU_Symbol): added data member useTreeFlag

2003-05-16  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_Symbol.cc (stackArguments): rewritten; handle tree case; use
	FOR_EACH_CONST() in ArgVec case
	(ruleRewrite): use ruleFree(); don't use getACU_DagNode()

2003-05-15  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_Symbol.cc (reduceArgumentsAndNormalize): rewritten; now
	return true for collapse and false owise

	* ACU_Symbol.hh (class ACU_Symbol): added decls for normalize()
	and copyReduceSubtermsAndNormalize()

	* ACU_Symbol.cc (memoStrategy): rewritten
	(normalize): added
	(complexStrategy): simplified using normalize()
	(memoStrategy): simplified using normalize()
	(normalizeAndComputeTrueSort): simplified using normalize()
	(copyAndReduceSubterms): rewritten
	(copyAndReduceSubterms): becomes copyReduceSubtermsAndNormalize()
	(memoStrategy): simplified using copyReduceSubtermsAndNormalize()
	(complexStrategy): simplified using
	copyReduceSubtermsAndNormalize()

	* ACU_TreeDagNode.cc (treeToArgVec): pass ASSIGNMENT to
	ACU_DagNode()

	* ACU_Symbol.cc (reduceArgumentsAndNormalize): use isFresh()
	(eqRewrite): use isFresh()
	(complexStrategy): use isFresh()
	(memoStrategy): use isFresh() (2 places)
	(normalizeAndComputeTrueSort): rewritten; only call
	computeTrueSort() on args and normalize if our normalization
	status is FRESH

	* ACU_BaseDagNode.hh (isFresh): added

	* ACU_Symbol.cc (computeBaseSort): use isTree()

2003-05-14  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_ExtensionInfo.hh (useUnmatched): deleted
	(class ACU_ExtensionInfo): deleted decls for convertToUnmatched(0
	and useUnmatched()

	* ACU_ExtensionInfo.cc (buildMatchedPortion): rewritten using
	iterators
	(convertToUnmatched): deleted

	* ACU_DagNode.cc (partialReplace): need to set normalization
	status to FRESH

	* ACU_TreeMatcher.cc (makeHighMultiplicityAssignment): use new
	ACU_DagNode() convention
	(tryToBindLastVariable): use new ACU_DagNode() convention
	(forcedLoneVariableCase): use new ACU_DagNode() convention

	* ACU_Subproblem.cc (oneVariableCase): use new ACU_DagNode()
	convention
	(computeAssignment): use new ACU_DagNode() convention
	(solveVariables): don't call setNormalizationStatus()

	* ACU_NonLinearLhsAutomaton.cc (match): use new ACU_DagNode()
	convention

	* ACU_Matcher.cc (forcedLoneVariableCase): use new ACU_DagNode()
	convention

	* ACU_ExtensionInfo.cc (buildUnmatchedPortion): use new
	ACU_DagNode() convention

	* ACU_GreedyMatcher.cc (greedyPureMatch): use new ACU_DagNode()
	convention

	* ACU_CollectorLhsAutomaton.cc (collect): use new ACU_DagNode()
	convention

	* ACU_DagNode.hh (ACU_DagNode): take NormalizationStatus arg

	* ACU_ExtensionInfo.cc (buildUnmatchedPortion): rewritten to
	handle tree case and use iterators

	* ACU_ExtensionInfo.hh (getUnmatched): deleted

	* ACU_MergeSort.cc (flattenSortAndUniquize): moved here

	* ACU_Normalize.cc (copyAndBinaryInsert): moved here

	* ACU_DagNode.hh (class ACU_DagNode): deleted decls for
	extensionNormalizeAtTop() and binaryInsert()

	* ACU_DagNormalization.cc (extensionNormalizeAtTop): deleted
	(binaryInsert): deleted

	* ACU_Symbol.cc (reduceArgumentsAndNormalize): removed EXTENSION
	case
	(complexStrategy): test for ACU_BaseDagNode::FRESH
	(memoStrategy): removed EXTENSION case

	* ACU_BaseDagNode.hh (class ACU_BaseDagNode): deleted EXTENSION
	from enum NormalizationStatus

	* ACU_DagNode.cc (partialReplace): simplified using
	buildUnmatchedPortion(); don't use EXTENSION normalization status
	(partialConstruct): simplified using buildUnmatchedPortion()

	* ACU_ExtensionInfo.hh (class ACU_ExtensionInfo): added decl for
	buildUnmatchedPortion()

	* ACU_ExtensionInfo.cc (buildUnmatchedPortion): added

2003-05-13  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_TreeDagNode.cc (copyEagerUptoReduced2): avoid treeToArgVec()
	in the case that our symbol is not eager
	(clearCopyPointers2): changed CantHappen() to Assert() now that we
	handle non-eager copies ourself

	* ACU_DagNode.cc (clearCopyPointers2): only need to clear copy
	pointer if we're eager - lazy argumnets don't get copied

2003-05-12  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_Symbol.cc (eqRewrite): simplified
	(complexStrategy): rewritten to avoid converting from tree to
	argvec form unless we need to evaluate aour args

	* ACU_TreeDagNode.cc (getHashValue): cache hash value

	* ACU_TreeDagNode.hh (class ACU_TreeDagNode): deleted decl for
	treeComputeBaseSort()
	(class ACU_TreeDagNode): added data member hashCache

	* ACU_TreeDagNode.cc (treeComputeBaseSort): deleted

	* ACU_Symbol.cc (computeBaseSort): use ACU_Tree::computeBaseSort()

	* ACU_TreeMatcher.cc (tryToBindLastVariable): use
	ACU_Tree::computeBaseSort()

	* ACU_CollectorLhsAutomaton.cc (collect): (ACU_Tree version)
	simplified

	* ACU_LhsAutomaton.cc (complete): removed SAT_MULT test and
	comment

	* ACU_LhsCompiler0.cc (tryToMakeNonLinearLhsAutomaton): removed
	SAT_MULT test and comment

	* ACU_NonLinearLhsAutomaton.cc (ACU_NonLinearLhsAutomaton):
	removed SAT_MULT part of Assert()

	* ACU_TreeMatcher.cc (treeMatch): deleted SAT_MULT Assert()

2003-05-06  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_DagOperations.cc (findFirstPotentialMatch): use
	Term::UNKNOWN

2003-05-05  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_LhsAutomaton.hh (class ACU_LhsAutomaton): redBlackMatch() ->
	treeMatch()

	* ACU_TreeMatcher.cc (redBlackMatch): becomes treeMatch()

	* ACU_Matcher.cc (match): redBlackOK -> treeMatchOK,
	redBlackMatch() -> treeMatch()

	* ACU_LhsAutomaton.cc: redBlackOK -> treeMatchOK

	* ACU_LhsAutomaton.hh (class ACU_LhsAutomaton): redBlackOK ->
	treeMatchOK

	* ACU_TreeMatcher.cc: remamed from ACU_RedBlackMatcher.cc

	* ACU_RedBlackMatcher.cc (eliminateBoundVariables): use deleteMult()
	(makeHighMultiplicityAssignment): use class ACU_Tree
	(redBlackMatch): use getTree()
	(eliminateGroundAliens): use deleteMult()
	(eliminateGroundedOutAliens): use deleteMult()
	(greedyMatch): use deleteMult()
	(tryToBindVariable): use deleteMult()
	(tryToBindLastVariable): use deleteMult()
	(eliminateBoundVariables): use ACU_Tree::find()
	(eliminateGroundAliens): use ACU_Tree::find()
	(eliminateGroundedOutAliens): use
	ACU_Tree::findFirstPotentialMatch()
	(greedyMatch): use ACU_Tree::findFirstPotentialMatch()
	(tryToBindVariable): use ACU_Tree::findGeqMult()
	(tryToBindLastVariable): use getSoleDagNode()

	* ACU_LhsAutomaton.hh (class ACU_LhsAutomaton): current becomes an
	ACU_Tree

	* ACU_GndLhsAutomaton.cc (match): use getTree()

	* ACU_ExtensionInfo.cc (convertToUnmatched): use getTree()

	* ACU_Term.cc (compareArguments): use getTree()

	* ACU_LhsAutomaton.hh (class ACU_LhsAutomaton): updated decl for
	makeHighMultiplicityAssignment()

	* ACU_NGA_LhsAutomaton.cc (match): use getTree()

	* ACU_NonLinearLhsAutomaton.cc (match): use getTree()

	* ACU_VarLhsAutomaton.cc (match): use getTree()

	* ACU_Flatten.cc (flattenSortAndUniquize): use getTree()

	* ACU_Normalize.cc (normalizeAtTop): use class ACU_Tree

	* ACU_FastMerge.cc (fastMerge): use getTree() (2 versions)

	* ACU_DagNode.hh (class ACU_DagNode): replace struct Pair with a
	typedef from ACU_Pair

	* ACU_Normalize.cc (insertAlien): use class ACU_Tree

	* ACU_DagNode.cc (compareArguments): use getTree()

	* ACU_Convert.cc: deleted

	* ACU_DagNode.hh (class ACU_DagNode): deleted decls for
	makeTree(), pow2min1(), makeTree()

	* ACU_BaseDagNode.cc (getSize): use getTree()

	* ACU_TreeDagNode.cc (recComputeBaseSort): deleted
	(arguments): use tree data member
	(getHashValue): use tree data member
	(overwriteWithClone): use tree data member
	(makeClone): use tree data member
	(compareArguments): use tree data member
	(stackArguments): use tree data member
	(markArguments): use ACU_Tree::mark()
	(treeToArgVec): use tree data member

	* ACU_TreeDagNode.hh (class ACU_TreeDagNode): use ACU_Tree data
	element
	(getRoot): becomes getTree()
	(class ACU_TreeDagNode): deleted decl for recComputeBaseSort()

	* ACU_Symbol.hh (computeMultSortIndex): deleted
	(computeSortIndex): deleted
	
===================================Maude80a===========================================

2003-05-02  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_Symbol.hh (class ACU_Symbol): added decl for rewriteAtTop()

	* ACU_Symbol.cc (rewriteAtTop): added
	(eqRewrite): use rewriteAtTop() to avoid having an
	ACU_ExtensionInfo on our stack frame
	(eqRewrite): simplified; we no longer assume that if we have
	standard strategy and our subject was produced by an assignment
	that we cannot be equation free; mbs can prevent exact sort
	calculation and setting of reduced flag
	(reduceArgumentsAndNormalize): only remove identity in
	ACU_DagNode::EXTENSION case

	* ACU_DagNode.cc (markArguments): avoid recursing on the first arg
	that shares our symbol

2003-05-01  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_TreeDagNode.cc (overwriteWithClone): use
	copySetRewritingFlags()
	(makeClone): use copySetRewritingFlags()

	* ACU_DagNode.cc (overwriteWithClone): use copySetRewritingFlags()
	and fastCopy()
	(makeClone): use copySetRewritingFlags() and fastCopy()

2003-04-30  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_LhsCompiler3.cc (findLongestIncreasingSequence): added
	comment to explain why calling subsumes() is safe even in the
	presence of external agencies that can bind variables in the
	subsumer
	
===================================Maude80===========================================

2003-03-28  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_LhsAutomaton.hh (class ACU_LhsAutomaton): deleted decl for
	copyMultiplicity()

	* ACU_Matcher.cc (fullMatch): call addSubjects() here
	(aliensOnlyMatch): call addSubjects() here
	(buildBipartiteGraph): don't call addSubjects() here
	(aliensOnlyMatch): check for trivial graph
	(match): expand copyMultiplicity() here since it's only called
	from this one place
	(copyMultiplicity): deleted

2003-03-27  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_Matcher.cc (fullMatch): check for trivial bipartite graph

2003-03-26  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_Subproblem.hh (noPatterns): added

	* ACU_Matcher.cc (forcedLoneVariableCase): now handle identity
	case here; no longer local_inline
	(match): don't handle lone variable identity case here

	* ACU_RedBlackMatcher.cc (forcedLoneVariableCase): code cleaning

	* ACU_Theory.hh: deleted fwd decl for class
	ACU_AlienAlienLhsAutomaton

	* ACU_DagNode.hh (class ACU_DagNode): deleted decl for
	findFirstOccurrence()

	* ACU_DagOperations.cc (findFirstOccurrence): deleted

	* ACU_Term.hh (class ACU_Term): deleted decl for
	tryToMakeAlienAlienLhsAutomaton()

	* ACU_LhsCompiler0.cc (tryToMakeAlienAlienLhsAutomaton): deleted
	(tryToMakeSpecialCaseAutomaton): don't call
	tryToMakeAlienAlienLhsAutomaton()

	* ACU_AlienAlienLhsAutomaton.cc: deleted

	* ACU_AlienAlienLhsAutomaton.hh: deleted

	* ACU_Matcher.cc (buildBipartiteGraph): new ACU_Subproblem()
	convention to get arround the probelm that currentMultipplicities
	can change

	* ACU_DagNode.cc (matchVariableWithExtension): new
	ACU_Subproblem() convention

	* ACU_Subproblem.hh (class ACU_Subproblem): added decl for
	addSubjects(); updated decl for ctor

	* ACU_Subproblem.cc (addSubjects): added
	(ACU_Subproblem): don't set currentMultiplicity here

	* ACU_LhsAutomaton.hh (class ACU_LhsAutomaton): updated decl for
	buildBipartiteGraph()

	* ACU_Matcher.cc (buildBipartiteGraph): take SubproblemAccumulator
	arg
	(fullMatch): new buildBipartiteGraph() convention
	(aliensOnlyMatch): new buildBipartiteGraph() convention

	* ACU_Subproblem.hh (class ACU_Subproblem): added decl for
	removePatternNode()

	* ACU_Subproblem.cc (removePatternNode): added

	* ACU_Matcher.cc (buildBipartiteGraph): force patterns that only
	have a single edge

2003-03-25  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_LhsAutomaton.hh (class ACU_LhsAutomaton): updated decls for
	forcedLoneVariableCase(), greedyPureMatch(),
	tryToBindLastVariable(), tryToBindVariable(), greedyMatch(),
	eliminateGroundedOutAliens(), eliminateGroundAliens(),
	eliminateBoundVariables()

	* ACU_RedBlackMatcher.cc (eliminateBoundVariables): simplified
	argument list
	(eliminateGroundAliens): simplified argument list
	(eliminateGroundedOutAliens): simplified argument list
	(greedyMatch): simplified argument list
	(greedyMatch): simpified call to greedyPureMatch()
	(tryToBindVariable): simplified argument list
	(makeHighMultiplicityAssignment): current -> root so we don't
	confuse arg with data member
	(tryToBindLastVariable): simplified argument list
	(greedyPureMatch): simplified argument list
	(greedyPureMatch): simplified calls to tryToBindLastVariable() and
	tryToBindVariable()
	(redBlackMatch): assignto data members rather than local variables
	for current and matchedMultiplicity
	(redBlackMatch): simplified calls to eliminateBoundVariables(),
	eliminateGroundAliens(), eliminateGroundedOutAliens(),
	forcedLoneVariableCase() and greedyMatch()
	(forcedLoneVariableCase): simplified argument list

	* ACU_LhsAutomaton.hh (class ACU_LhsAutomaton): added decl for
	red-black version of forcedLoneVariableCase()
	(class ACU_LhsAutomaton): added data members current,
	nrUnboundVariables and matchedMultiplicity so we don't have to
	drag these values around as arguments at match time

	* ACU_RedBlackMatcher.cc (forcedLoneVariableCase): added red-black
	version
	(redBlackMatch): use forcedLoneVariableCase()

	* ACU_Matcher.cc (match): pass returnedSubproblem arg to
	redBlackMatch()

	* ACU_RedBlackMatcher.cc (redBlackMatch): now take
	returnedSubproblem arg

2003-03-24  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_AlienAlienLhsAutomaton.cc (match): use safeCast()

	* ACU_ExtensionInfo.cc (copy): use safeCast()

	* ACU_Matcher.cc (match): use safeCast()

	* ACU_Term.cc (normalizeAliensAndFlatten): use safeCast() (3
	places)

	* ACU_DagNode.cc (partialReplace): use safeCast()
	(partialConstruct): use safeCast()
	(matchVariableWithExtension): use safeCast()

	* ACU_NonLinearLhsAutomaton.cc (match): use safeCast() (2 places)

	* ACU_GndLhsAutomaton.cc (ACU_GndLhsAutomaton): don't initialize
	trueFailure
	(match): test extensionInfo == 0 rather than trueFailure
	(dump): don't dump trueFailure

	* ACU_GndLhsAutomaton.hh (class ACU_GndLhsAutomaton): deleted data
	member trueFailure

	* ACU_CollectorLhsAutomaton.cc (ACU_CollectorLhsAutomaton): added
	Assert to check for sort constraint freeness
	(collect): don't check for sort constraint freeness (both
	versions)
	(collect): use getUniqueSortIndex() (both versions)

	* ACU_LhsCompiler0.cc (tryToMakeCollectorLhsAutomaton): require
	that top symbol be sort constraint free

2003-03-21  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_Term.hh (class ACU_Term): added decl for
	tryToMakeSpecialCaseAutomaton()

	* ACU_LhsCompiler0.cc (tryToMakeSpecialCaseAutomaton): added
	(compileLhs2): simplified using tryToMakeSpecialCaseAutomaton()

	* ACU_NGA_LhsAutomaton.cc (match): call setValidAfterMatch()

	* ACU_VarLhsAutomaton.cc (match): call setValidAfterMatch()

	* ACU_GndLhsAutomaton.cc (match): call setValidAfterMatch()

	* ACU_TreeDagNode.hh (ACU_TreeDagNode): added Assert() to check
	that we don't make an ACU_TreeDagNode with single argument

	* ACU_NonLinearLhsAutomaton.cc (match): fixed symmetric bug
	(dump): dump pureSort
	(match): deleted superfluous setValidAfterMatch()

	* ACU_RedBlackMatcher.cc (greedyPureMatch): fixed bug where we
	were creating ACU node with single argument when setting extension

	* ACU_NonLinearLhsAutomaton.cc (match): restructured

2003-03-20  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_Term.hh (class ACU_Term): updated decl for
	tryToMakeNonLinearLhsAutomaton()

	* ACU_LhsCompiler0.cc (tryToMakeNonLinearLhsAutomaton): don't take
	matchAtTop arg since now it must be true
	(tryToMakeNonLinearLhsAutomaton): allow LIMIT_SORT, check that
	multiplicity <= SAT_MULT; new ACU_NonLinearLhsAutomaton() calling
	convention
	(compileLhs2): use new tryToMakeNonLinearLhsAutomaton() convention

	* ACU_NonLinearLhsAutomaton.cc (match): check getMaxMult() here so
	that we can return false if there is no subject with enough
	multiplicity

	* ACU_NonLinearLhsAutomaton.hh (class ACU_NonLinearLhsAutomaton):
	updated decl for ctor

	* ACU_NonLinearLhsAutomaton.cc (ACU_NonLinearLhsAutomaton): don't
	take matchAtTop (must be true) or collapsePossible (must be false)

	* ACU_NonLinearLhsAutomaton.hh (class ACU_NonLinearLhsAutomaton):
	deleted data members topSymbol and matched; added data member
	pureSort
	(class ACU_NonLinearLhsAutomaton): deleted decl for treeMatch()

	* ACU_NonLinearLhsAutomaton.cc (match): use
	makeHighMultiplicityAssignment() rather than treeMatch()
	(match): deleted non-extension case; this will now be handled in
	the general greedy matcher
	(dump): don't dump topSymbol
	(match): use getSymbol rather than topSymbol
	(ACU_NonLinearLhsAutomaton): init pureSort; allow LIMIT_SORT
	(ACU_NonLinearLhsAutomaton): don't init topSymbol
	(treeMatch): deleted

	* ACU_Subproblem.cc (~ACU_Subproblem): use FOR_EACH_CONST
	(solveVariables): use FOR_EACH_CONST

	* ACU_RedBlackMatcher.cc (greedyMatch): new convention for
	greedyPureMatch()

	* ACU_LhsAutomaton.hh (class ACU_LhsAutomaton): updated decl for
	greedyPureMatch(); made makeHighMultiplicityAssignment() protected

	* ACU_RedBlackMatcher.cc (greedyPureMatch): return bool now that
	we no longer try to make a distiction between true failure and
	UNDECIDED

	* ACU_LhsAutomaton.hh (class ACU_LhsAutomaton): updated decls for
	decidePhase1FailureMode() and decidePhase2FailureMode()

	* ACU_GreedyMatcher.cc (decidePhase1FailureMode): rewritten
	(greedyPureMatch): use new decidePhase1FailureMode() convention
	(decidePhase2FailureMode): simplified to avoid nasty bug where a
	unit variable could be given a lower sort subject when it actually
	needs a higher sort subject in order for the match to succeed and
	we could end up returning false when a match is really possible
	(greedyPureMatch): use new decidePhase2FailureMode() convention

2003-03-19  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_LhsAutomaton.hh (class ACU_LhsAutomaton): added decls for
	decidePhase1FailureMode() and decidePhase2FailureMode()

	* ACU_GreedyMatcher.cc (decidePhase1FailureMode): added
	(decidePhase2FailureMode): added
	(greedyPureMatch): use decidePhase1FailureMode() and
	decidePhase2FailureMode()

	* ACU_Matcher.cc (match): don't pass returnUndecidedOnFail arg to
	greedyPureMatch() 

	* ACU_GreedyMatcher.cc (greedyMatch): don't pass
	returnUndecidedOnFail arg to greedyPureMatch()

	* ACU_LhsAutomaton.hh (class ACU_LhsAutomaton): updated decl for
	greedyPureMatch()

	* ACU_GreedyMatcher.cc (greedyPureMatch): don't take
	returnUndecidedOnFail since greedyMatch() already checks for true
	and wasted effort is slight and rare

	* ACU_Matcher.cc (eliminateGroundAliens): use FOR_EACH_CONST
	(eliminateGroundedOutAliens): use FOR_EACH_CONST
	(eliminateGroundedOutAliens): rewritten to be almost symmetric
	with red-black version
	(computeTotalMultiplicity): use FOR_EACH_CONST
	(copyMultiplicity): use FOR_EACH_CONST
	(fullMatch): use FOR_EACH_CONST
	(handleElementVariables): use FOR_EACH_CONST

	* ACU_GreedyMatcher.cc (greedyMatch): rewritten to be mostly
	symmetric with red-black version

	* ACU_LhsAutomaton.cc (dump): dump redBlackOK and collectorSeen

	* ACU_LhsCompiler3.cc (compileGreedyAndFullCases): new complete()
	convention

	* ACU_LhsCompiler2.cc (compileAliensOnlyCase): new complete()
	convention

	* ACU_LhsCompiler1.cc (compileLhs3): new complete() convention

	* ACU_LhsAutomaton.hh (class ACU_LhsAutomaton): updated decl for
	complete()

	* ACU_LhsAutomaton.cc (ACU_LhsAutomaton): init collectorSeen
	(addTopVariable): update collectorSeen
	(complete): new redBlackOK calculation

	* ACU_LhsAutomaton.hh (class ACU_LhsAutomaton): updated decl for
	addTopVariable()
	(class ACU_LhsAutomaton): added data member collectorSeen

	* ACU_LhsCompiler1.cc (compileLhs3): use new addTopVariable()
	convention

	* ACU_LhsAutomaton.cc (ACU_LhsAutomaton): init redBlackOK = true
	(addAbstractionVariable): falsify redBlackOK
	(addGroundedOutAlien): falsify redBlackOK if alien unstable
	(addNonGroundAlien): falsify redBlackOK if alien unstable

2003-03-18  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_LhsCompiler3.cc (compileGreedyAndFullCases): use new
	complete() convention

	* ACU_LhsCompiler2.cc (compileAliensOnlyCase): use new complete()
	convention

	* ACU_LhsCompiler1.cc (compileLhs3): use new complete() convention

	* ACU_LhsAutomaton.hh (class ACU_LhsAutomaton): updated decl for
	complete()

	* ACU_LhsAutomaton.cc (complete): take redBlackPossible arg; we
	can't rely on strategy == LONE_VARIABLE beacuse of variable
	abstraction

	* ACU_LhsCompiler1.cc (compileLhs3): use empty() rather than
	length() == 0

2003-03-17  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_TreeDagNode.cc (recComputeBaseSort): fixed nasty bug where
	we were using getLeft() twice instead of getRight() and computing
	the wrong sort

	* ACU_LhsAutomaton.cc (ACU_LhsAutomaton): don't set redBlackOK
	here
	(complete): set redBlackOK here

	* ACU_RedBlackMatcher.cc (redBlackMatch): call greedyMatch()

2003-03-12  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_LhsAutomaton.hh (class ACU_LhsAutomaton): added decl for
	makeHighMultiplicityAssignment()
	(class ACU_LhsAutomaton): added data member matched

	* ACU_RedBlackMatcher.cc (makeHighMultiplicityAssignment): added
	(tryToBindLastVariable): added high multiplicity cases

2003-03-11  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_LhsAutomaton.hh (class ACU_LhsAutomaton): added decl for
	tryToBindLastVariable()

	* ACU_RedBlackMatcher.cc (tryToBindLastVariable): added

	* ACU_LhsAutomaton.hh (class ACU_LhsAutomaton): updated decls for
	eliminateBoundVariables(), eliminateGroundAliens(),
	eliminateGroundedOutAliens() and greedyMatch(); added decl for
	tryToBindVariable()
	(class ACU_LhsAutomaton): updated decl for greedyPureMatch()

	* ACU_RedBlackMatcher.cc (eliminateBoundVariables): update
	matchedMultiplicity
	(eliminateGroundAliens): update matchedMultiplicity
	(greedyMatch): update matchedMultiplicity
	(tryToBindVariable): added

	* ACU_LhsAutomaton.hh (class ACU_LhsAutomaton): added decls for
	red-black versions of greedyPureMatch() and greedyMatch(); updated
	decl for eliminateBoundVariables()

	* ACU_RedBlackMatcher.cc (greedyMatch): added red-black version
	(eliminateBoundVariables): keep track of number of unbound
	variables rather than making a linked list of them.
	(eliminateBoundVariables): use iterators
	(eliminateBoundVariables): use FOR_EACH_CONST() macro
	(eliminateGroundAliens): use FOR_EACH_CONST() macro
	(eliminateGroundedOutAliens): use FOR_EACH_CONST() macro
	(greedyPureMatch): added red-black version

2003-03-10  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_Matcher.cc (eliminateGroundAliens): use iterators
	(eliminateGroundedOutAliens): use iterators
	(eliminateGroundedOutAliens): rearrange tests; now only look at
	multiplicity after we have a match; if current multiplicity is too
	small we can rewturn false since ground out alien must  match a
	unique subject subterm

	* ACU_LhsAutomaton.hh (class ACU_LhsAutomaton): added decls for
	red-black versions of eliminateBoundVariables(),
	eliminateGroundAliens() and eliminateGroundedOutAliens()

	* ACU_RedBlackMatcher.cc (eliminateBoundVariables): added
	red-black version
	(eliminateGroundAliens): added red-black version
	(eliminateGroundedOutAliens): added red-black version

	* ACU_LhsAutomaton.cc (ACU_LhsAutomaton): initialize redBlackOK

	* ACU_LhsAutomaton.hh (class ACU_LhsAutomaton): added decl for
	redBlackMatch()

	* ACU_RedBlackMatcher.cc (redBlackMatch): added stub

	* ACU_LhsAutomaton.hh (class ACU_LhsAutomaton): added data member
	redBlackOK

	* ACU_Matcher.cc (match): use redBlackOK and redBlackMatch()

2003-03-07  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_NGA_LhsAutomaton.hh (class ACU_NGA_LhsAutomaton): delete
	data memeber trueFailure

	* ACU_NGA_LhsAutomaton.cc (ACU_NGA_LhsAutomaton): added Assert()s
	to check to stripper term is non-ground and stable
	(match): do full match if collect() fails; this fixes a nasty bug
	where we tried to continue but collect() has destroyed the
	iterator
	(ACU_NGA_LhsAutomaton): don't initialize trueFailure

	* ACU_VarLhsAutomaton.cc (ACU_VarLhsAutomaton): allow trueFailure
	if stripper variable has pure sort

	* ACU_LhsCompiler0.cc (tryToMakeCollectorLhsAutomaton): no longer
	require stripper variable to have unit or pure sort

	* ACU_VarLhsAutomaton.cc (match): do full match if collect()
	fails; this fixes a nasty bug where we tried to continue but
	collect() has destroyed the iterator
	(ACU_VarLhsAutomaton): changed definition of trueFailure to take
	account of the fact that failures due to collect() never test
	trueFailure
	(ACU_VarLhsAutomaton): added Assert() to check that stripper
	variable can't take identity

	* ACU_LhsCompiler0.cc (tryToMakeCollectorLhsAutomaton): chnage
	requirement on collect variable to have unbounded sort rather than
	pure or limit sort. The is a wweaker condition that is now allowed
	because we gave up on the fast sort computation trick.

	* ACU_GndLhsAutomaton.cc (ACU_GndLhsAutomaton): added Assert() to
	check that stripper term is ground

	* ACU_CollectorLhsAutomaton.cc (ACU_CollectorLhsAutomaton): added
	Assert() to check that collector has unbounded sort

	* ACU_NGA_LhsAutomaton.hh (class ACU_NGA_LhsAutomaton): deleted
	data member local

	* ACU_NGA_LhsAutomaton.cc (match): use getLocal()
	(ACU_NGA_LhsAutomaton): don't initialize local

	* ACU_LhsAutomaton.hh (getLocal): added
	(getLocal2): added

	* ACU_NGA_LhsAutomaton.hh (class ACU_NGA_LhsAutomaton): deleted
	data members topSymbol and collapsePossible; added data member
	trueFailure

	* ACU_NGA_LhsAutomaton.cc (match): use getSymbol()
	(match): use getCollapsePossible()
	(dump): don't dump topSymbol or collapsePossible
	(ACU_NGA_LhsAutomaton): don't initialize topSymbol or
	collapsePossible; initialize trueFailure
	(match): reorganized search loops using trueFailure

2003-03-06  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_NGA_LhsAutomaton.cc (match): use new collapse() convention

	* ACU_GndLhsAutomaton.cc (ACU_GndLhsAutomaton): initialize
	trueFailure
	(match): use trueFailure
	(dump): dump trueFailure

	* ACU_GndLhsAutomaton.hh (class ACU_GndLhsAutomaton): added data
	member trueFailure

	* ACU_VarLhsAutomaton.cc (match): rewrote argVec case
	(dump): dump trueFailure

	* ACU_VarLhsAutomaton.hh (class ACU_VarLhsAutomaton): added data
	member trueFailure

	* ACU_VarLhsAutomaton.cc (ACU_VarLhsAutomaton): don't initialize
	topSymbol or collapsePossible
	(dump): don't dump topSymbol or collapsePossible
	(match): use use getSymbol() and getCollapsePossible(); use new
	collapse() convention
	(match): fixed bug where we were returing false even though
	assigning multiple things to stripper, or putting stuff in
	extension or applying a membership might have produced a match.
	(ACU_VarLhsAutomaton): initialize trueFailure

	* ACU_VarLhsAutomaton.hh (class ACU_VarLhsAutomaton): deleted data
	members topSymbol and collapsePossible

	* ACU_GndLhsAutomaton.cc (match): use new collapse() convention

	* ACU_CollectorLhsAutomaton.hh (collapse): use getSymbol()
	(class ACU_CollectorLhsAutomaton): updated decl for collapse()

	* ACU_GndLhsAutomaton.cc (ACU_GndLhsAutomaton): don't initialize
	topSymbol or collapsePossible
	(dump): don't dump topSymbol or collapsePossible
	(match): fixed bug where we assumed red-black collect failing
	implied no match, where as some of teh suff might have been put in
	the extension
	(match): use getSymbol() (two places) and getCollapsePossible()

	* ACU_GndLhsAutomaton.hh (class ACU_GndLhsAutomaton): deleted data
	members topSymbol and collapsePossible

	* ACU_LhsAutomaton.hh (getSymbol): added
	(getCollapsePossible): added

	* ACU_CollectorLhsAutomaton.cc (collect): major simplification; we
	no longer try to do sort check as we build, instead we use
	argVecComputeBaseSort() afterwards; this can lose in the case that
	we are not in an error free component (argVecComputeBaseSort() has
	to look at each arg) and we are not reduced (didn't need to have
	th exact base sort); but it simplifies things greatly
	(ACU_CollectorLhsAutomaton): swich of sort checks for kind
	variables

2003-03-05  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_Symbol.cc (computeBaseSort): complete rewrite using
	argVecComputeBaseSort(); this fixes a nasty bug where we assumed
	that ACU_DagNodes with getNormalizationStatus() == ASSIGNMENT
	could not be in the error sort - no longer true since we allowed
	variables at the kind level

	* ACU_DagNode.cc (argVecComputeBaseSort): unroll first iteration
	of standand case loop to move initial case branch out of loop

	* ACU_DagNode.hh (class ACU_DagNode): added decl for
	argVecComputeBaseSort()

	* ACU_DagNode.cc (argVecComputeBaseSort): added

	* ACU_TreeDagNode.hh (class ACU_TreeDagNode): deleted decl for
	makeDelete(); updated decl for treeComputeBaseSort()

	* ACU_Symbol.cc (computeBaseSort): use new treeComputeBaseSort()
	convention

	* ACU_TreeDagNode.cc (treeComputeBaseSort): return index of
	computed sort rather than calling setSortIndex()
	(makeDelete): deleted

	* ACU_CollectorLhsAutomaton.cc (collect): (tree version) use
	treeComputeBaseSort(); don't use makeDelete(); use setSortIndex();
	don't use repudiateSortInfo()

	* ACU_Symbol.cc (computeBaseSort): use treeComputeBaseSort()

	* ACU_TreeDagNode.hh (class ACU_TreeDagNode): updated decls for
	recComputeBaseSort() and treeComputeBaseSort()

	* ACU_TreeDagNode.cc (computeBaseSort): computeMultBaseSort() ->
	computeMultSortIndex(); computeBaseSort() -> computeSortIndex() (2
	places)
	(computeBaseSort): becomes recComputeBaseSort()
	(computeBaseSort): treeComputeBaseSort()

	* ACU_NonLinearLhsAutomaton.cc (treeMatch): computeMultBaseSort()
	-> computeMultSortIndex() (2 places)

	* ACU_Symbol.hh (computeBaseSort): renamed to computeSortIndex()
	to avoid confusion
	(computeMultBaseSort): renamed to computeMultSortIndex() for the
	sake on consistancy

	* ACU_TreeDagNode.cc (computeBaseSort): use new
	computeMultBaseSort() calling convention

	* ACU_NonLinearLhsAutomaton.cc (treeMatch): use new
	computeMultBaseSort() calling convention (2 places)

	* ACU_Symbol.hh (computeMultBaseSort): rewritten
	(class ACU_Symbol): updated decl for computeMultBaseSort()

2003-03-04  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_Term.hh (class ACU_Term): updated decl for
	tryToMakeAlienAlienLhsAutomaton()

	* ACU_LhsCompiler0.cc (compileLhs2): use new alien-alien automata
	convention
	(tryToMakeAlienAlienLhsAutomaton): use new
	ACU_AlienAlienLhsAutomaton() convention

	* ACU_AlienAlienLhsAutomaton.cc (ACU_AlienAlienLhsAutomaton): call
	ACU_LhsAutomaton()
	(match): call ACU_LhsAutomation::match() instead of fullMatch()
	(dump): call ACU_LhsAutomaton::dump() rather than
	HeuristicLhsAutomaton::dump()

	* ACU_AlienAlienLhsAutomaton.hh: derive from ACU_LhsAutomaton
	rather than HeuristicLhsAutomaton; updated decl for ctor

	* ACU_CollectorLhsAutomaton.cc (dump): call
	ACU_LhsAutomaton::dump() rather than HeuristicLhsAutomaton::dump()

	* ACU_LhsCompiler0.cc (tryToMakeCollectorLhsAutomaton): use new
	ACU_GndLhsAutomaton() convention
	(tryToMakeCollectorLhsAutomaton): use new ACU_VarLhsAutomaton()
	convention
	(tryToMakeCollectorLhsAutomaton): use new ACU_NGA_LhsAutomaton()
	convention
	(compileLhs2): use new compilation conventions for collector
	automata

	* ACU_NGA_LhsAutomaton.cc (ACU_NGA_LhsAutomaton): use new
	ACU_CollectorLhsAutomaton() convention
	(match): call ACU_LhsAutomation::match() instead of fullMatch() (3
	places)

	* ACU_NGA_LhsAutomaton.hh (class ACU_NGA_LhsAutomaton): updated
	decl for ctor

	* ACU_VarLhsAutomaton.cc (ACU_VarLhsAutomaton): use new
	ACU_CollectorLhsAutomaton() convention
	(match): call ACU_LhsAutomation::match() instead of fullMatch() (2
	places)

	* ACU_VarLhsAutomaton.hh (class ACU_VarLhsAutomaton): updated decl
	for ctor

	* ACU_GndLhsAutomaton.cc (ACU_GndLhsAutomaton): use new
	ACU_CollectorLhsAutomaton() convention
	(match): call ACU_LhsAutomation::match() instead of fullMatch()

	* ACU_GndLhsAutomaton.hh (class ACU_GndLhsAutomaton): updated decl
	for ctor

	* ACU_CollectorLhsAutomaton.cc (ACU_CollectorLhsAutomaton): call
	ACU_LhsAutomaton()

	* ACU_CollectorLhsAutomaton.hh (class ACU_CollectorLhsAutomaton):
	derive from ACU_LhsAutomaton rather than HeuristicLhsAutomaton;
	updated decl for ctor

2003-03-03  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_LhsCompiler0.cc (compileLhs2): use new
	ACU_NonLinearLhsAutomaton convention
	(tryToMakeNonLinearLhsAutomaton): use new
	ACU_NonLinearLhsAutomaton convention

	* ACU_NonLinearLhsAutomaton.cc (ACU_NonLinearLhsAutomaton): call
	ACU_LhsAutomaton()
	(treeMatch): call ACU_LhsAutomaton::match() instead of fullMatch()
	(match): call ACU_LhsAutomaton::match() instead of fullMatch()
	(dump): call instead ACU_LhsAutomaton::dump() of
	HeuristicLhsAutomaton::dump()

	* ACU_NonLinearLhsAutomaton.hh (class ACU_NonLinearLhsAutomaton):
	derive from ACU_LhsAutomaton rather than HeuristicLhsAutomaton
	(class ACU_NonLinearLhsAutomaton): updated decl for ctor

	* ACU_LhsCompiler1.cc (compileLhs3): don't return automaton

	* ACU_Term.hh (class ACU_Term): updated decl for compileLhs3()

	* ACU_LhsCompiler1.cc (compileLhs3): take ACU_LhsAutomaton rather
	than creating it

	* ACU_LhsCompiler0.cc (compileLhs2): create ACU_LhsAutomaton;
	use new compileLhs3() convention

	* ACU_LhsCompiler1.cc (compileLhs3): use new ACU_LhsAutomaton()
	convention

	* ACU_LhsAutomaton.cc (ACU_LhsAutomaton): clear
	uniqueCollapseAutomaton rather than setting it

	* ACU_LhsAutomaton.hh (class ACU_LhsAutomaton): updated decl for
	ctor; added decl for addUniqueCollapseAutomaton()
	(addUniqueCollapseAutomaton): added

2003-02-25  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_VarLhsAutomaton.cc: removed #pragma
	(match): updated Assert()

	* ACU_VarLhsAutomaton.hh: removed #pragma

	* ACU_TreeDagNode.cc (computeBaseSort): updated Assert()
	(treeToArgVec): updated Assert()

	* ACU_TreeDagArgumentIterator.cc (argument): updated Assert()
	(next): updated Assert()

	* ACU_Term.cc: removed #pragma
	(Term): updated Assert()
	(normalizeAliensAndFlatten): updated Assert()
	(compareArguments): updated Assert()s (both versions)
	(insertAbstractionVariables): updated DebugAdvisoryCheck()

	* ACU_Term.hh: removed #pragma

	* ACU_Symbol.cc: removed #pragma
	(makeDagNode): updated Assert()
	(computeBaseSort): updated Assert()s
	(normalizeAndComputeTrueSort): updated Assert()

	* ACU_Symbol.hh: removed #pragma

	* ACU_Subproblem.cc: removed #pragma

	* ACU_Subproblem.hh: removed #pragma

	* ACU_RhsAutomaton.cc: removed #pragma
	(buildArguments): updated Assert()s

	* ACU_RhsAutomaton.hh: removed #pragma

	* ACU_NonLinearLhsAutomaton.cc: removed #pragma
	(ACU_NonLinearLhsAutomaton): updated Assert()
	(fillOutExtensionInfo): updated Assert()
	(treeMatch): updated Assert()s
	(match): updated Assert()s

	* ACU_NonLinearLhsAutomaton.hh: removed #pragma

	* ACU_NGA_LhsAutomaton.cc: removed #pragma
	(match): updated Assert()

	* ACU_NGA_LhsAutomaton.hh: removed #pragma

	* ACU_MergeSort.cc (mergeSortAndUniquize): updated Assert()

	* ACU_Matcher.cc (eliminateGroundedOutAliens): updated Assert()
	(forcedLoneVariableCase): updated Assert()s
	(match): updated Assert()s

	* ACU_LhsCompiler3.cc (findGreedySequence): updated Assert()

	* ACU_LhsCompiler2.cc (compileAliensOnlyCase): updated Assert()s
	(findConstraintPropagationSequence): updated Assert()

	* ACU_LhsCompiler1.cc (compileLhs3): updated Assert()

	* ACU_LhsAutomaton.cc: removed #pragma
	(complete): updated Assert()

	* ACU_LhsAutomaton.hh: removed #pragma

	* ACU_GreedyMatcher.cc (greedyPureMatch): updated Assert()s

	* ACU_GndLhsAutomaton.cc: removed #pragma
	(match): updated Assert()

	* ACU_GndLhsAutomaton.hh: removed #pragma

	* ACU_ExtensionInfo.cc (buildMatchedPortion): updated Assert()s
	(convertToUnmatched): updated Assert()s

	* ACU_ExtensionInfo.hh (useUnmatched): updated Assert()

	* ACU_DagOperations.cc (findFirstOccurrence): updated Assert()
	(findFirstPotentialMatch): updated Assert()
	(binarySearch): updated Assert() (both versions)

	* ACU_DagNormalization.cc (extensionNormalizeAtTop): updated Assert()

	* ACU_DagNode.cc: removed #pragma
	(compareArguments): updated Assert()s
	(markArguments): updated Assert()
	(copyWithReplacement): updated Assert()
	(partialReplace): updated Assert()s
	(partialConstruct): updated Assert()

	* ACU_DagNode.hh: removed #pragma

	* ACU_DagArgumentIterator.cc: removed #pragma
	(argument): updated Assert()
	(next): updated Assert()

	* ACU_DagArgumentIterator.hh: removed #pragma

	* ACU_CollectorLhsAutomaton.cc: removed #pragma
	(collect): updated Assert()s

	* ACU_CollectorLhsAutomaton.hh: removed #pragma

	* ACU_CollapseMatcher.cc (uniqueCollapseMatch): updated Assert()s
	(multiwayCollapseMatch): updated Assert()s

	* ACU_ArgumentIterator.cc: removed #pragma
	(argument): updated Assert()
	(next): updated Assert()

	* ACU_ArgumentIterator.hh: removed #pragma

	* ACU_AlienAlienLhsAutomaton.cc: removed #pragma

	* ACU_AlienAlienLhsAutomaton.hh: removed #pragma
	
===================================Maude79===========================================

2003-02-20  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_Flatten.cc (flattenSortAndUniquize): use fastCopy(); handle
	ACU_TreeDagNode* case; don't bother trying to combine flattened in
	argument list with current run
	(flattenSortAndUniquize): can't use fastCopy() after all - need to
	multiply by multiplicity
	(flattenSortAndUniquize): removed optimize involving d+1 as it
	fails due to strict iterator checking

	* ACU_DagNormalization.cc (copyAndBinaryInsert): don't treat
	nrSourceArgs > 1 as a special case
	(extensionNormalizeAtTop): fixed longstanding performance bug
	where we were copying an argArray rather than taking its reference
	(extensionNormalizeAtTop): handle ACU_TreeDagNode* case

2003-02-13  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_Convert.cc (makeTree): don't use fast version of
	ACU_RedBlackNode() since we don't have the maxMult value to hand

2003-02-12  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_Flatten.cc (flattenSortAndUniquize): moved here

	* ACU_MergeSort.cc (mergeSortAndUniquize): moved here
	(sortAndUniquize): moved here

	* ACU_Convert.cc (makeTree): added optional code for checking
	red-black property

	* ACU_ExtensionInfo.cc (convertToUnmatched): reimplemented to
	handle unmatched dag root case

2003-02-11  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_ExtensionInfo.cc (copy): reimplemented to handle unmatched
	dag root case
	(makeClone): reimplemented to handle unmatched dag root case
	(buildMatchedPortion): reimplemented to handle ACU_TreeDagNode
	case

	* ACU_DagNode.hh (class ACU_DagNode): deleted decl for
	makeExtensionInfo()

	* ACU_DagNode.cc (makeExtensionInfo): deleted

	* ACU_TreeDagNode.hh (class ACU_TreeDagNode): deleted decl for
	makeExtensionInfo()

	* ACU_TreeDagNode.cc (makeExtensionInfo): deleted

	* ACU_BaseDagNode.hh (class ACU_BaseDagNode): added decl for
	makeExtensionInfo()

	* ACU_BaseDagNode.cc (makeExtensionInfo): added

	* ACU_TreeDagNode.cc (partialConstruct): reimplemented without
	using treeToArgVec()

	* ACU_TreeDagNode.hh (class ACU_TreeDagNode): deleted decls for
	argVecToTree(), overwriteWithInsert() and makeTree()

	* ACU_TreeDagNode.cc (argVecToTree): deleted
	(pow2min1): deleted
	(makeTree): deleted
	(overwriteWithInsert): deleted

	* ACU_NewNormalize.cc: deleted

	* ACU_Normalize.cc (insertAlien): use makeTree() in place of
	argVecToTree() (2 places)
	(insertAlien): use consInsert() in place of overwriteWithInsert()
	(normalizeAtTop): use makeTree() in place of argVecToTree()
	(normalizeAtTop): removed alternative merge case code

	* ACU_DagNode.hh (class ACU_DagNode): added decl for makeTree()
	(both versions) and pow2min1()

	* ACU_Convert.cc: created

	* ACU_Normalize.cc (insertAlien): use CONVERT_THRESHOLD
	(insertAlien): fixed bug in alterate code when we fall below the
	threshold

	* ACU_DagNode.hh (class ACU_DagNode): added MERGE_THRESHOLD to
	enum Sizes; THRESHOLD -> CONVERT_THRESHOLD

	* ACU_Normalize.cc (normalizeAtTop): use MERGE_THRESHOLD

2003-02-10  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_Normalize.cc (normalizeAtTop): don't convert back to
	re-black ofer merging two red-black trees

	* ACU_NonLinearLhsAutomaton.cc (treeMatch):
	setNormalizationStatus(ACU_DagNode::ASSIGNMENT) now that we are
	extract hi mult arguments in order

2003-02-07  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_DagNode.hh (class ACU_DagNode): added ctor decl for Pair
	(Pair): added
	(Pair): added default ctor

	* ACU_NonLinearLhsAutomaton.hh (class ACU_NonLinearLhsAutomaton):
	added data member matched

	* ACU_NonLinearLhsAutomaton.cc (treeMatch): rewritten
	(match): use treeMatch()

2003-02-06  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_NonLinearLhsAutomaton.hh (class ACU_NonLinearLhsAutomaton):
	added decl for treeMatch()

	* ACU_NonLinearLhsAutomaton.cc (treeMatch): added

2003-02-05  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_TreeDagNode.cc (partialReplace): simplified using new
	ACU_Extension interface

	* ACU_NonLinearLhsAutomaton.cc (match): use new ACU_Extension
	interface

	* ACU_ExtensionInfo.hh (clearMatched): deleted
	(addMatched): deleted
	(getMatched): deleted
	(clear): set unmatched to 0 rather than clearing matched
	(reset): set unmatched to 0 rather than clearing matched
	(class ACU_ExtensionInfo): deleted data member matched; added data
	member unmatched
	(setUnmatched): added DagNode* version
	(getUnmatched): added DagNode* version
	(useUnmatched): use unmatched

2003-02-04  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_Symbol.cc: (complexStrategy): use new normalizeAtTop() (2
	places)
	(reduceArgumentsAndNormalize): use new normalizeAtTop()
	(eqRewrite): use new normalizeAtTop()
	(memoStrategy): use new normalizeAtTop() (3 places)
	(normalizeAndComputeTrueSort): use new normalizeAtTop()

	* ACU_DagNode.hh (class ACU_DagNode): added THRESHHOLD to enum Sizes

	* ACU_TreeDagNode.hh (class ACU_TreeDagNode): made ctor public

	* ACU_Normalize.cc (normalizeAtTop): reimplemented
	(insertAlien): added

2003-02-03  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_Normalize.cc: created

	* ACU_DagNode.hh (fastCopy): moved here
	(fastCopy): added ACU_FastIter version
	(class ACU_DagNode): added decls for additional versions of fastMerge()

	* ACU_FastMerge.cc: created

	* ACU_TreeDagNode.cc (markArguments): rewritten to do a preorder
	traversal, ignoring marked red-black nodes
	(partialReplace): added replacement == matched arg heuristic

2003-01-31  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_NewNormalize.cc (normalizeAtTop): fixed stupid brace bug in
	two red-black tree case

	* ACU_NonLinearLhsAutomaton.cc (match): fixed bug where we weren't
	dealing with the case that we matched everything

	* ACU_TreeDagNode.cc (partialReplace): fixed bug where we were not
	testing r->getMultiplicity() against 1

	* ACU_NewNormalize.cc (normalizeAtTop): added code for two
	red-black trees case

	* ACU_Term.cc (analyseCollapses): becomes analyseCollapses2()

	* ACU_Term.hh (class ACU_Term): analyseCollapses() ->
	analyseCollapses2()

	* ACU_TreeDagArgumentIterator.cc: moved here

	* ACU_TreeDagArgumentIterator.hh: moved here

	* ACU_TreeDagNode.cc: moved here

	* ACU_TreeDagNode.hh: moved here

	* ACU_Theory.hh: added fwd decls for ACU_TreeDagNode and
	ACU_TreeDagArgumentIterator

2003-01-30  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_CollectorLhsAutomaton.cc (collect): ACU_SlowIter ->
	ACU_Stack

	* ACU_CollectorLhsAutomaton.hh (class ACU_CollectorLhsAutomaton):
	ACU_SlowIter -> ACU_Stack

	* ACU_NGA_LhsAutomaton.cc (match): use
	ACU_RedBlackNode::findFirstPotentialMatch rather than
	ACU_TreeDagNode::findFirstPotentialMatch

2003-01-29  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_VarLhsAutomaton.cc (match): getArgument() -> getDagNode()

	* ACU_Term.cc (compareArguments): getArgument() -> getDagNode()

	* ACU_NonLinearLhsAutomaton.cc (match): getArgument() ->
	getDagNode()

	* ACU_NGA_LhsAutomaton.cc (match): getArgument() -> getDagNode()
	(2 places)

	* ACU_DagNode.cc (compareArguments): getArgument() -> getDagNode()

2003-01-28  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_ExtensionInfo.hh (class ACU_ExtensionInfo): added decl for
	convertToUnmatched()

	* ACU_ExtensionInfo.cc (convertToUnmatched): added

	* ACU_ExtensionInfo.hh (useUnmatched): added

	* ACU_NewNormalize.cc (normalizeAtTop): use isTree() (2 places)

	* ACU_DagNode.cc (getACU_DagNode): use isTree()

	* ACU_NonLinearLhsAutomaton.cc (match): added red-black case

2003-01-27  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_VarLhsAutomaton.cc (match): added red-black case

	* ACU_GndLhsAutomaton.cc (match): added red-black case

	* ACU_NGA_LhsAutomaton.cc (match): fixed if nesting bug; it hadn't
	bitten because collect() seldom return false;

	* ACU_Symbol.cc (eqRewrite): use isTree()

	* ACU_NGA_LhsAutomaton.cc (match): use isTree()

	* ACU_ExtensionInfo.hh (clear): use getSize()
	(reset): use getSize()
	(clearMatched): added

	* ACU_BaseDagNode.cc: created

	* ACU_ExtensionInfo.hh (ACU_ExtensionInfo): take ACU_BaseDagNode*
	(class ACU_ExtensionInfo): added struct Matched and data member
	matched

2003-01-23  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_DagNode.cc (compareArguments): rewritten to use left to
	right comparison and handle ACU_TreeDagNodes

	* ACU_Term.cc (compareArguments): (DagNode* version) rewritten to
	use left to right comparison and handle ACU_TreeDagNodes
	(compareArguments): (Term*) rewritten to use iterators and left to
	right comparison

2003-01-22  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_BaseDagNode.hh (isTree): added

2003-01-14  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_Symbol.cc (eqRewrite): fixed casting bug in tree case

2003-01-13  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_Symbol.hh (computeBaseSort): added
	(computeMultBaseSort): added

	* ACU_ExtensionInfo.hh (ACU_ExtensionInfo): added ACU_TreeDagNode*
	version

	* ACU_Symbol.cc (eqRewrite): handle TREE case

	* ACU_CollectorLhsAutomaton.cc (collect): added ACU_TreeDagNode*
	version

2003-01-12  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_NGA_LhsAutomaton.cc (match): added support for
	ACU_TreeDagNodes

	* ACU_CollectorLhsAutomaton.hh (class ACU_CollectorLhsAutomaton):
	added decl for ACU_TreeDagNode* version of collect

2003-01-10  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_Symbol.cc (eqRewrite): rewritten to use new normalizeAtTop()

	* ACU_DagNode.hh (class ACU_DagNode): added decl for new version
	of normalizeAtTop()

	* ACU_NewNormalize.cc: created

	* ACU_DagNode.cc (getACU_DagNode): made into a global function

	* ACU_DagNode.hh (class ACU_DagNode): made getACU_DagNode() a
	friend function rather than a static member function

	* ACU_VarLhsAutomaton.cc (match): used getACU_DagNode()

	* ACU_Term.cc (compareArguments): used getACU_DagNode() +
	const_cast<DagNode*>()

	* ACU_Subproblem.cc (solveVariables): used getACU_DagNode()

	* ACU_NonLinearLhsAutomaton.cc (match): used getACU_DagNode()

	* ACU_NGA_LhsAutomaton.cc (match): used getACU_DagNode()

	* ACU_Matcher.cc (match): used getACU_DagNode()

	* ACU_GndLhsAutomaton.cc (match): used getACU_DagNode()

	* ACU_AlienAlienLhsAutomaton.cc (match): used getACU_DagNode()

	* ACU_Term.hh (symbol): replaced static_cast<ACU_Symbol>() with
	safeCast() 

	* ACU_Symbol.cc (ruleRewrite): used getACU_DagNode()
	(reduceArgumentsAndNormalize): used getACU_DagNode()
	(eqRewrite): used getACU_DagNode()
	(complexStrategy): used getACU_DagNode()
	(memoStrategy): used getACU_DagNode()
	(computeBaseSort): used getACU_DagNode()
	(normalizeAndComputeTrueSort): used getACU_DagNode()
	(stackArguments): used getACU_DagNode()

	* ACU_DagNormalization.cc (flattenSortAndUniquize): used
	getACU_DagNode()
	(normalizeAtTop): used getACU_DagNode() in many places
	(extensionNormalizeAtTop): used getACU_DagNode()

	* ACU_DagOperations.cc (eliminateSubject): use getACU_DagNode()
	rather than static_cast<ACU_DagNode*>

	* ACU_DagNode.cc (compareArguments): handle TREE case

	* ACU_DagNode.hh (class ACU_DagNode): added decl for
	getACU_DagNode()

	* ACU_DagNode.cc (getACU_DagNode): added

2003-01-08  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_Symbol.cc (eqRewrite): added crude hack to see if we can
	convert to re-black form and back

	* ACU_DagNode.hh (class ACU_DagNode): made ACU_TreeDagNode a friend

	* ACU_Theory.hh: added ACU_BaseDagNode;

	* ACU_DagNode.cc (~ACU_DagNode): deleted

	* ACU_DagNode.hh (class ACU_DagNode): rewritten, deriving from
	ACU_BaseDagNode

	* ACU_BaseDagNode.hh: created

2003-01-07  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_LhsCompiler0.cc (tryToMakeCollectorLhsAutomaton): use new
	ACU_NGA_LhsAutomaton() convention

	* ACU_NGA_LhsAutomaton.cc (ACU_NGA_LhsAutomaton): replaced
	stripperTopSymbol with stripperTerm
	(match): rewritten using stripperTerm
	(dump): sump stripperTerm

	* ACU_NGA_LhsAutomaton.hh (class ACU_NGA_LhsAutomaton): replaced
	stripperTopSymbol with stripperTerm
	(class ACU_NGA_LhsAutomaton): updated decl for
	ACU_NGA_LhsAutomaton()

	* ACU_GreedyMatcher.cc (greedyMatch): use partialCompare() and
	findFirstPotentialMatch()

	* ACU_Matcher.cc (eliminateGroundedOutAliens): use
	partialCompare() and findFirstPotentialMatch()
	(aliensOnlyMatch): use partialCompare() and
	findFirstPotentialMatch()
	(buildBipartiteGraph): use partialCompare() and
	findFirstPotentialMatch()

	* ACU_LhsAutomaton.cc (addGroundedOutAlien): assign to term rather
	than topSymbol
	(addNonGroundAlien): assign to term rather than topSymbol

	* ACU_LhsAutomaton.hh (class ACU_LhsAutomaton): term replaces
	topSymbol in struct NonGroundAlien

	* ACU_DagOperations.cc (findFirstPotentialMatch): added

===================================Maude78==================================================

2003-01-02  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_Term.hh (class ACU_Term): updated decl for
	tryToMakeCollectorLhsAutomaton()

	* ACU_LhsCompiler0.cc (compileLhs2): use new
	tryToMakeCollectorLhsAutomaton() calling convention
	(tryToMakeCollectorLhsAutomaton): Allow collector variable to
	occur in context and/or condition as long as stripper is a ground
	term and we have no extension. This is ok because the ground term
	must strip exactly one occurence of itself from subject with the
	rest of the subject providing a unique binding for the collector

2002-12-20  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_CollectorLhsAutomaton.cc (collect): optimized no sort check
	case
	(collect): optimized sort check case

2002-12-19  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_DagOperations.cc (binarySearch): (Term* version): use
	setOnLs(), setOnGeq()

2002-12-17  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_LhsAutomaton.hh (class ACU_LhsAutomaton): added decl for
	handleElementVariables()

	* ACU_Matcher.cc (handleElementVariables): added
	(fullMatch): use handleElementVariables()
	(buildBipartiteGraph): don't handle element variables here

	* ACU_DagNormalization.cc (copyAndBinaryInsert): rewritten using
	resizeWithoutPreservation()
	(fastMerge): rewritten using resizeWithoutPreservation()

2002-12-16  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_DagNormalization.cc (copyAndBinaryInsert): use fastCopy() in
	place of STL copy() (3 places)
	(fastMerge): use use fastCopy() in place of STL copy() (2 places)

	* ACU_DagNode.hh (class ACU_DagNode): added decl for fastCopy()

	* ACU_DagNormalization.cc (fastCopy): added

	* ACU_DagNode.cc (markArguments): rewritten to avoid seperate
	iteration count

2002-11-22  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_Subproblem.hh (class ACU_Subproblem): added decl for
	noVariableCase(); updated decl for oneVariableCase()

	* ACU_Subproblem.cc (noVariableCase): added
	(oneVariableCase): generalized to handle the case where there may
	be multiple varibales but only one is unbound
	(extractDiophantineSystem): rewritten to handle a number of
	special cases efficiently

	* ACU_Matcher.cc (buildBipartiteGraph): use new addEdge() calling
	convention
	(buildBipartiteGraph): use new addEdge() calling convention

	* ACU_Subproblem.hh (class ACU_Subproblem): updated decl for
	addEdge()

	* ACU_Subproblem.cc (addEdge): take difference rather than global
	and local bindings

2002-11-21  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_Matcher.cc (buildBipartiteGraph): fixed bug we introduced by
	checking for matchable outside of the right scope

	* ACU_Subproblem.hh (class ACU_Subproblem): updated decl for
	addPatternNode()

	* ACU_Subproblem.cc (addPatternNode): return index to created
	pattern node

	* ACU_Matcher.cc (buildBipartiteGraph): treat unbound variables
	that take exactly one subject as non-ground aliens
	(fullMatch): don't treat unbound variables that take exactly one
	subject as top variables

2002-11-20  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_DagNode.cc (matchVariableWithExtension): now check & use
	sort bound

2002-11-19  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_Subproblem.cc (oneVariableCase): partly optimized using
	iterators

	* ACU_DagNormalization.cc (copyAndBinaryInsert): rewritten using
	iterators and copy() algorithm template
	(copyAndBinaryInsert): put back missing expandBy()
	(fastMerge):rewritten using iterators and copy() algorithm
	template

	* ACU_NonLinearLhsAutomaton.hh (class ACU_NonLinearLhsAutomaton):
	updated decl for fillOutExtensionInfo()

	* ACU_NonLinearLhsAutomaton.cc (match): rewritten using iterators
	to replace CONST_ARG_VEC_HACK()
	(fillOutExtensionInfo): pass chosen as a const
	ArgVec<ACU_DagNode::Pair>::const_iterator
	(match): new fillOutExtensionInfo() calling convention

2002-11-18  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_DagOperations.cc (findFirstOccurrence): replaced
	CONST_ARG_VEC_HACK() with const_iterator 
	(binarySearch): (both versions) replaced CONST_ARG_VEC_HACK() with
	const_iterator

	* ACU_Matcher.cc (multiplicityChecks): rewritten using
	const_iterator in place of CONST_ARG_VEC_HACK()

	* ACU_NonLinearLhsAutomaton.cc (fillOutExtensionInfo): rewritten
	using const_iterator in place of CONST_ARG_VEC_HACK()

	* ACU_DagNode.cc (compareArguments): need to iterate backwards for
	consistancy

	* ACU_RhsAutomaton.cc (buildArguments): rewritten using iterator
	in place of ARG_VEC_HACK()

	* ACU_DagNode.cc (compareArguments): rewritten using
	iterators in place of CONST_ARG_VEC_HACK()s
	(partialReplace): rewritten using
	CONST_ARG_VEC_HACK()/ARG_VEC_HACK()

	* ACU_CollectorLhsAutomaton.cc (collect): rewritten using
	itterators in place of CONST_ARG_VEC_HACK()/ARG_VEC_HACK()
	
===================================Maude77==================================================

2002-11-07  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_Subproblem.cc (solveVariables):
	DagNode::okToCollectGarbage() -> MemoryCell::okToCollectGarbage()

2002-11-06  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_Subproblem.cc (oneVariableCase): try using set() rather
	than Pair(); on sparc this saves 1 ld instruction in loop - wins
	under quantify but loses in actual run - must be a sparc
	scheduling problem

	* ACU_DagNode.hh (Pair): deleted as it loses
	(set): added

	* ACU_Subproblem.cc (oneVariableCase): use ACU_DagNode::Pair() to
	see if enables g++ to generate better code

	* ACU_DagNode.hh (Pair): added

	* ACU_Subproblem.hh (class ACU_Subproblem): added decl for
	oneVariableCase() and updated decl for extractDiophantineSystem()

	* ACU_Subproblem.cc (oneVariableCase): added
	(extractDiophantineSystem): use oneVariableCase(); take
	RewritingContext& since we need to pass it to oneVariableCase()

2002-11-05  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_Subproblem.cc (extractDiophantineSystem): deleted
	excessively cute trivial case code; if we have no subjects but can
	succeed by binding unbound variables to the identity, do the
	binding here rather than in solveVariables()
	(solveVariables): don't do identity binding in null system case;
	code reorganized to share unbinding loop
	(extractDiophantineSystem): use clear()

	* ACU_Matcher.cc (multiplicityChecks): replaced VECTOR_HACK() with
	Vector<int>::iterator

	* ACU_RhsAutomaton.cc (buildArguments): replaced
	CONST_VECTOR_HACK() with Vector<Argument>::const_iterator

2002-10-28  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_LhsCompiler0.cc (compileLhs2): added DebugAdvisory() for
	when we fail to produce heuristic ACU automaton

2002-10-16  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_Symbol.hh (class ACU_Symbol): postInterSymbolPass() ->
	postOpDeclarationPass()

	* ACU_Symbol.cc (postInterSymbolPass): becomes
	postOpDeclarationPass() since sort tables arem't computed at
	postInterSymbolPass time

2002-10-07  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_DagNode.cc (copyWithReplacement): complex version: rewritten
	to fix a serious bug where we were relying on unstackable flags to
	figure out when args had been stacked and needed
	replacement. Since unstackable flags can be set after stacking
	this approach fails badly, corrupting the dag node

2002-10-04  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_DagNode.hh (class ACU_DagNode): updated decl for the more
	complex copyWithReplacement()

	* ACU_DagNode.cc (copyWithReplacement): rewritten to handle
	situation where only some args are stacked.

	* ACU_Symbol.cc (stackArguments): we no longer stack all
	arguments; if we have frozen arguments we don't stack anything;
	otherwise we stack only those arguments that have not been flagged
	as unstackable

2002-10-03  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_DagNode.hh (class ACU_DagNode): updated decl for
	stackArguments()

	* ACU_DagNode.cc (stackArguments): handle respectFrozen argument
	
===================================Maude76==================================================

2002-08-02  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_Term.cc (compileRhs2): added code to flag last use of each
	source

2002-07-24  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_LhsCompiler3.cc (findLongestIncreasingSequence): same as
	below

	* ACU_LhsCompiler0.cc (tryToMakeAlienAlienLhsAutomaton): pass
	sameVariableSet = true to calls of subsumes() since both subterms
	are from the same pattern
	
===================================Maude74==================================================

2002-05-13  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_Symbol.hh (class ACU_Symbol): added decl for multiplicities
	version of makeDagNode()

	* ACU_Symbol.cc (makeDagNode): added multiplicities version; this
	is so that derived symbol classes can build new AC_DagNodes from
	old ones with reasonable efficiency

2002-05-10  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_Symbol.hh (class ACU_Symbol): added decl for
	reduceArgumentsAndNormalize()
	(class ACU_Symbol): added defaults for strategy and memo args

	* ACU_Symbol.cc (reduceArgumentsAndNormalize): added; this is a
	special purpose function the all ACU builtin symbols to get an ACU
	dag in normal form
	
===================================Maude72==================================================

2002-03-11  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_Term.cc: deleted explicit template instantiation

	* ACU_Subproblem.cc: deleted explicit template instantiation

	* ACU_RhsAutomaton.cc: deleted explicit template instantiation

	* ACU_DagNode.cc: deleted explicit template instantiation

	* ACU_LhsAutomaton.cc: deleted explicit template instantiations
	
===================================Maude71==================================================

2001-12-10  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_DagNode.hh (class ACU_DagNode): made class
	ACU_DagArgumentIterator a friend

	* ACU_Term.hh (class ACU_Term): made class ACU_ArgumentIterator a
	friend
	
===================================Maude69==================================================

2001-04-03  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_DagNode.hh (class ACU_DagNode): added decl for
	Vector<RedexPosition> version of copyWithReplacement()

	* ACU_DagNode.cc (copyWithReplacement): added
	(Vector<RedexPosition> version)
	
===================================Engine66==================================================

2001-03-08  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_Symbol.hh (class ACU_Symbol): added decl for
	stackArguments()

	* ACU_Symbol.cc (stackArguments): added
	
===================================Engine65==================================================

2001-01-26  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_DagNode.hh (class ACU_DagNode): updated decl for
	markArguments() and made it private

	* ACU_DagNode.cc (markArguments): rewritten with new semantics
	
===================================Engine64==================================================

2000-08-02  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_DagNode.cc (matchVariableWithExtension): don't pass
	inErrorSort arg to ACU_Subproblem()

	* ACU_Subproblem.cc (ACU_Subproblem): no longer take inErrorSort
	arg
	(dump): don't dump inErrorSort data member
	(solveVariables): don't test inErrorSort (2 places)

	* ACU_Subproblem.hh (class ACU_Subproblem): ctor decl no longer
	has inErrorSort flag
	(class ACU_Subproblem): deleted data member inErrorSort

	* ACU_Matcher.cc (buildBipartiteGraph): don't pass inErrorSort
	flag to ACU_Subproblem()

	* ACU_LhsAutomaton.cc (ACU_LhsAutomaton): don't take inErrorSort
	arg
	(dump): don't dump inErrorSort data member

	* ACU_LhsAutomaton.hh (class ACU_LhsAutomaton): deleted data
	member inErrorSort
	(class ACU_LhsAutomaton): updared ctor decl

	* ACU_LhsCompiler1.cc (compileLhs3): no longer care if pattern is
	in error sort; don't pass inErrorSort flags to ACU_LhsAutomaton()

	* ACU_LhsCompiler0.cc (compileLhs2): no longer care if pattern is
	in error sort
	(tryToMakeNonLinearLhsAutomaton): no longer care if pattern is
	in error sort

	* ACU_Symbol.cc (complexStrategy): greatly simplified now that we
	no longer treat last strategy zero specially when term is in the
	error sort
	(memoStrategy): ditto

	* ACU_DagNode.hh (class ACU_DagNode): assumption "our sort 
	(which may not be known) is not the error sort." for the
	ASSIGNMENT case is no longer true

2000-07-31  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_Symbol.cc (computeBaseSort): don't handle union sorts
	
===================================Engine61==================================================

2000-07-28  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_RhsAutomaton.cc (remapIndices): added

	* ACU_RhsAutomaton.hh (class ACU_RhsAutomaton): added decl for
	remapIndices()

2000-07-26  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_LhsCompiler1.cc (compileLhs3): use
	getNrProtectedVariables() instead of nrVariables()

	* ACU_LhsCompiler0.cc (tryToMakeAlienAlienLhsAutomaton): use
	getNrProtectedVariables() instead of nrVariables()
	(tryToMakeCollectorLhsAutomaton): use getNrProtectedVariables()
	instead of nrVariables()

	* ACU_Term.cc (insertAbstractionVariables): use
	makeProtectedVariable() instead of makeAbstractionVariable()
	(compileRhs2): use makeConstructionIndex() instead of
	allocateIndex()

2000-07-25  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_Term.cc (findAvailableTerms): don't insert ground terms into
	availableTerms since we can't do left->right sharing on them

	* ACU_LhsAutomaton.cc (dump): cast Bool member before print so
	they don't print out as chars

	* ACU_RhsAutomaton.cc (construct): don't call buildAliens()
	(replace): don't call buildAliens()
	(dump): don't call RhsAutomaton::dump()

	* ACU_Term.hh (class ACU_Term): deleted decl for compileRhs()

	* ACU_Term.cc (compileRhs): deleted
	
===================================Engine60==================================================

2000-07-18  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_LhsCompiler0.cc (tryToMakeNonLinearLhsAutomaton): use
	getConditionVariables() 
	(tryToMakeCollectorLhsAutomaton): use getConditionVariables()

	* ACU_LhsCompiler1.cc (compileLhs3): use getConditionVariables()

2000-07-12  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_Term.cc (compileRhs2): call addRhsAutomaton()

2000-07-11  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_Term.cc (findAvailableTerms): added
	(compileRhs2): added

	* ACU_Term.hh (class ACU_Term): added declarations for
	findAvailableTerms() and compileRhs2()
	
===================================Engine59==================================================

	
2000-07-05  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_LhsCompiler0.cc (compileLhs2): call to compileLhs2() becomes
	call to compileLhs3()

	* ACU_LhsCompiler1.cc (compileLhs2): becomes compileLhs3()

	* ACU_Term.hh (class ACU_Term): old compileLhs2() -> compileLhs3() 

	* ACU_LhsCompiler0.cc (compileLhs): becomes compileLhs2()

	* ACU_Term.hh (class ACU_Term): compileLhs() -> compileLhs2()

2000-06-23  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_Term.cc (compileRhs): modifiedIndex() -> getModifiedIndex()

	* ACU_VarLhsAutomaton.cc (ACU_VarLhsAutomaton): index() ->
	getIndex()
	(ACU_VarLhsAutomaton): lookupSort() -> getSort()

	* ACU_LhsCompiler1.cc (analyseConstraintPropagation): index() ->
	getIndex()
	(compileLhs2): index() -> getIndex()

	* ACU_LhsCompiler0.cc (tryToMakeCollectorLhsAutomaton): index() ->
	getIndex()
	(tryToMakeNonLinearLhsAutomaton): index() -> getIndex()
	(tryToMakeNonLinearLhsAutomaton): lookupSort() -> getSort()
	(tryToMakeCollectorLhsAutomaton): lookupSort() -> getSort()

	* ACU_LhsAutomaton.cc (addTopVariable): lookupSort() -> getSort()
	(addTopVariable): index() -> getIndex()

	* ACU_CollectorLhsAutomaton.cc (ACU_CollectorLhsAutomaton):
	index() -> getIndex()
	(ACU_CollectorLhsAutomaton): lookupSort() -> getSort()
	
===================================Engine58==================================================

2000-03-17  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_VarLhsAutomaton.hh (class ACU_VarLhsAutomaton): use
	NO_COPYING() macro; ifdef'd dump() decl

	* ACU_Term.cc (dump): ifdef'd

	* ACU_Term.hh (class ACU_Term): use NO_COPYING() macro; ifdef'd
	dump() decl

	* ACU_Subproblem.cc (dump): ifdef'd

	* ACU_Subproblem.hh (class ACU_Subproblem): use NO_COPYING()
	macro; ifdef'd dump() decl

	* ACU_RhsAutomaton.cc (dump): ifdef'd

	* ACU_RhsAutomaton.hh (class ACU_RhsAutomaton): use NO_COPYING()
	macro; ifdef'd dump() decl

	* ACU_NonLinearLhsAutomaton.cc (dump): ifdef'd

	* ACU_NonLinearLhsAutomaton.hh (class ACU_NonLinearLhsAutomaton):
	use NO_COPYING() macro; ifdef'd dump() decl

	* ACU_NGA_LhsAutomaton.cc (dump): ifdef'd

	* ACU_NGA_LhsAutomaton.hh (class ACU_NGA_LhsAutomaton): use
	NO_COPYING() macro; ifdef'd dump() decl

	* ACU_LhsAutomaton.cc (dump): ifdef'd

	* ACU_LhsAutomaton.hh (class ACU_LhsAutomaton): use NO_COPYING()
	macro; ifdef'd dump() decl

	* ACU_GndLhsAutomaton.cc (dump): ifdef'd

	* ACU_GndLhsAutomaton.hh (class ACU_GndLhsAutomaton): use
	NO_COPYING() macro; ifdef'd dump() decl 

	* ACU_CollectorLhsAutomaton.cc (dump): ifdef'd

	* ACU_CollectorLhsAutomaton.hh (class ACU_CollectorLhsAutomaton):
	use NO_COPYING() macro; ifdef'd dump() decl

	* ACU_AlienAlienLhsAutomaton.cc (dump): ifdef'd

	* ACU_AlienAlienLhsAutomaton.hh (class
	ACU_AlienAlienLhsAutomaton): use NO_COPYING() macro; ifdef'd
	dump() decl

	* ACU_Symbol.cc (complexStrategy): AdvisoryCheck() -> IssueAdvisory()
	(memoStrategy): AdvisoryCheck() -> IssueAdvisory()

2000-03-13  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_NonLinearLhsAutomaton.cc (match): fixed nasty bug:
	if (nrArgs == 1 || args[0].multiplicity == fastMult) should be
	if (nrArgs == 1 && args[0].multiplicity == fastMult)
	
===================================Engine56==================================================

2000-01-31  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_Subproblem.cc (solveVariables): allow collection of garbage
	in fail case to avoid build up of failed solutions
	
===================================Engine54==================================================

1999-11-03  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_Symbol.hh (class ACU_Symbol): added decl for memoStrategy()

	* ACU_Symbol.cc (memoStrategy): added
	(complexStrategy): simplified using revised MemoTable
	(memoStrategy): simplified using revised MemoTable

1999-11-01  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_Symbol.cc (eqRewrite): use standardStrategy()

1999-10-29  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_Symbol.cc (ACU_Symbol): use new AssociativeSymbol
	conventions
	
===================================Engine53==================================================

1999-10-26  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_LhsCompiler1.cc (analyseConstraintPropagation):
	VariableTerm::dynamicCast() -> dynamic_cast<VariableTerm*>()
	(compileLhs2): VariableTerm::dynamicCast() ->
	dynamic_cast<VariableTerm*>()

	* ACU_LhsCompiler0.cc (tryToMakeNonLinearLhsAutomaton):
	VariableTerm::dynamicCast() -> dynamic_cast<VariableTerm*>()
	(tryToMakeCollectorLhsAutomaton): VariableTerm::dynamicCast() ->
	dynamic_cast<VariableTerm*>() (*2)

	* ACU_Term.cc (compileRhs): VariableTerm::dynamicCast() ->
	dynamic_cast<VariableTerm*>()
	(insertAbstractionVariables): VariableTerm::dynamicCast() ->
	dynamic_cast<VariableTerm*>()

	* ACU_Symbol.cc (ACU_Symbol): added memoFlag arg

	* ACU_Symbol.hh (class ACU_Symbol): added memoFlag arg to ctor
	decl

1999-10-19  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_DagNode.cc (getHashValue): added

	* ACU_DagNode.hh (class ACU_DagNode): added decl for
	getHashValue()
	
===================================Engine52==================================================

1999-08-02  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_LhsAutomaton.hh (class ACU_LhsAutomaton): decl for
	topVariableCompare() replaced by decl for topVariableLt()

	* ACU_LhsAutomaton.cc (complete): use STL sort function
	(topVariableCompare): becomes topVariableLt()

	* ACU_Term.hh (class ACU_Term): decl for pairCompare() replaced by
	decl for pairLt()

	* ACU_Term.cc (normalize): use STL sort function
	(pairCompare): becomes pairLt()

1999-06-08  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_Symbol.hh (class ACU_Symbol): added decl for complexStrategy()

	* ACU_Symbol.cc (complexStrategy): added, taking guts from eqRewrite()
	(eqRewrite): rewritten using complexStrategy()

	* ACU_NonLinearLhsAutomaton.cc (match): CONST_ARG_VEC_HACK
	(fillOutExtensionInfo): CONST_ARG_VEC_HACK
	(match): fastMult hack - register copy of multiplicity to avoid
	reloading after writes to memory

	* ACU_VarLhsAutomaton.cc (match): very minor optimization using
	temporary to hold pointer to (potentially) stripped term

	* ACU_DagOperations.cc (eliminateSubject): updated calling
	convention for binarySearch() (2 places)
	(eliminateArgument): updated calling convention for binarySearch()

	* ACU_DagNormalization.cc (copyAndBinaryInsert): updated calling
	convention for binarySearch()
	(binaryInsert): updated calling convention for binarySearch()

	* ACU_GndLhsAutomaton.cc (match): updated calling convention for
	binarySearch()

	* ACU_NGA_LhsAutomaton.cc (match): updated calling
	convention for findFirstOccurrence()

	* ACU_Matcher.cc (eliminateGroundedOutAliens): updated calling
	convention for findFirstOccurrence()
	(aliensOnlyMatch): updated calling convention for
	findFirstOccurrence()
	(buildBipartiteGraph): updated calling convention for
	findFirstOccurrence()
	(eliminateGroundAliens): updated calling convention for
	binarySearch()

	* ACU_GreedyMatcher.cc (greedyMatch): updated calling convention
	for findFirstOccurrence()

	* ACU_AlienAlienLhsAutomaton.cc (match): updated calling convention
	for findFirstOccurrence() (2 places)

	* ACU_DagNode.hh (class ACU_DagNode): updated decls for
	findFirstOccurrence() and binarySearch (both versions)

	* ACU_DagOperations.cc (findFirstOccurrence): made into member
	function; use CONST_ARG_VEC_HACK()
	(binarySearch): (both versions): made into member function; use
	CONST_ARG_VEC_HACK()

1999-06-07  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_CollectorLhsAutomaton.cc (collect): simplified the case
	where there's only one unstripped arg and no new ACU_DagNode is
	needed
	(collect): loses so try another rearrangement
	(collect): yet another rearrangement
	(collect): 4th attempt
	(collect): 5th attempt

1999-06-03  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_DagNormalization.cc (fastMerge): take ACU_DagNode*
	rather than ArgVec<Pair>& for both args
	(normalizeAtTop): updated calling convention for fastMerge()
	(flattenSortAndUniquize): fixed bug that we introduced, since we
	were originally calling mergeSortAndUniquize() on newArray rather
	than argArray; now swap them before the call.

	* ACU_DagNode.hh (class ACU_DagNode): updated
	copyAndBinaryInsert() decl

	* ACU_DagNormalization.cc (copyAndBinaryInsert): take ACU_DagNode*
	rather than ArgVec<Pair>& as 1st arg
	(normalizeAtTop): pass ACU_DagNode* rather than ArgVec<Pair> to
	copyAndBinaryInsert() (2 places)

	* ACU_DagNode.hh (class ACU_DagNode): updated decl for
	mergeSortAndUniquize()

	* ACU_DagNormalization.cc (mergeSortAndUniquize): get rid of
	runs arg and use runsBuffer directly
	(sortAndUniquize): don't pass runsBuffer to mergeSortAndUniquize()
	(flattenSortAndUniquize): don't pass runsBuffer to
	mergeSortAndUniquize()
	(extensionNormalizeAtTop): don't pass runsBuffer to
	mergeSortAndUniquize()

	* ACU_DagNode.hh (class ACU_DagNode): updated decl for
	mergeSortAndUniquize(), no longer static

	* ACU_DagNormalization.cc (mergeSortAndUniquize): removed argArray
	arg; now going to be a member function
	(sortAndUniquize): call mergeSortAndUniquize() like a member
	function
	(flattenSortAndUniquize): call mergeSortAndUniquize() like a member
	function
	(extensionNormalizeAtTop): call mergeSortAndUniquize() like a member
	function

1999-06-01  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_DagNode.hh (class ACU_DagNode): update decl for binaryInsert()

	* ACU_DagNormalization.cc (binaryInsert): moved here as it its
	only used for normalization
	(binaryInsert): first arg deleted; made non-static
	(extensionNormalizeAtTop): use new binaryInsert() calling convention

	* ACU_DagNode.cc (partialReplace): added ARG_VEC_HACK
	(partialReplace): changed for() loop into do-while loop

	* ACU_CollectorLhsAutomaton.cc (collect): replaced SPEED_HACK with
	CONST_ARG_VEC_HACK and ARG_VEC_HACK for cleaness

	* ACU_DagNode.cc (compareArguments): replaced SPEED_HACK with
	CONST_ARG_VEC_HACKs for cleaness
	(markArguments): replaced SPEED_HACK with CONST_ARG_VEC_HACK for
	cleaness
	(markArguments): converted for() loop into do-while since we
	always have at least 1 arg

	* ACU_Matcher.cc (multiplicityChecks): replaced SPEED_HACKs with
	CONST_ARG_VEC_HACK and VECTOR_HACK for cleaness

	* ACU_RhsAutomaton.cc (buildArguments): replaced SPEED_HACK with
	ARG_VEC_HACK and CONST_VECTOR_HACK for cleaness

	* ACU_DagNormalization.cc (fastMerge): add heursitic to try and
	avoid full merge
	(fastMerge): removed previous heursitic as it seems to lose on
	average

	* ACU_DagNode.hh (class ACU_DagNode): added decl for fastMerge()

	* ACU_DagNormalization.cc (fastMerge): added
	(normalizeAtTop): call fastMerge()

	* ACU_DagNode.hh (class ACU_DagNode): updated decls for
	binarySearch() (both versions) and copyAndBinaryInsert()

	* ACU_DagNormalization.cc (copyAndBinaryInsert): use ARG_VEC_HACKs

	* ACU_DagOperations.cc (binarySearch): (both versions) made first
	arg const

	* ACU_DagNormalization.cc (normalizeAtTop): fix bug where we were
	using copyAndBinaryInsert() even when the arg to be flattened in
	had arity > 1
	(copyAndBinaryInsert): make first arg const

1999-05-28  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_DagNormalization.cc (copyAndBinaryInsert): fixed bug; we
	were searching in argArray rarther than source
	(normalizeAtTop): rearranged if statements to favor common cases

	* ACU_DagNode.hh (class ACU_DagNode): added decl for copyAndBinaryInsert()

	* ACU_DagNormalization.cc (fastNormalizeAtTop): added
	(copyAndBinaryInsert): added
	(flattenSortAndUniquize): no longer local inline
	(sortAndUniquize): no longer local inline
	(normalizeAtTop): incorporate fastNormalizeAtTop()
	(fastNormalizeAtTop): deleted

1999-05-16  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_DagNode.cc (markArguments): added SPEED_HACK

	* ACU_AlienAlienLhsAutomaton.cc: find first occurence of second
	symbol before entering outermost loop

	* ACU_CollectorLhsAutomaton.cc (ACU_CollectorLhsAutomaton): set
	noSortChecks flag if the collector variable has a sort that is the
	unique maximal sort in an error free component
	(ACU_CollectorLhsAutomaton): indicate "sort checks off" by setting
	collectorSort to 0
	(collect): handle "sort checks off" in the 3 cases with superfast
	loops in the main case
	(dump): handle "sort checks off"

1999-05-13  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_DagNode.cc (makeClone): copy theory byte
	(overwriteWithClone): copy theory byte

1999-05-12  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_Symbol.hh (class ACU_Symbol): computeTrueSort() ->
	normalizeAndComputeTrueSort()

	* ACU_Symbol.cc (computeTrueSort): become
	normalizeAndComputeTrueSort()
	(normalizeAndComputeTrueSort): use fastComputeTrueSort()

1999-05-11  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_RhsAutomaton.cc (buildArguments): made local_inline
	(buildArguments): added SPEED_HACK

===================================Engine49==================================================

1999-04-18  Steven Eker  <eker@goo.csl.sri.com>

	* Unmade previous chnage in all files due to huge number of
	functions that should have been in-lined but weren't (ans not
	reported either!) length(), expandTo(), contractTo()

1999-03-14  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_Subproblem.cc: try commenting out template decls

	* ACU_LhsAutomaton.cc: try commenting out template decls

	* ACU_RhsAutomaton.cc: try commenting out template decls

	* ACU_DagNode.cc: try commenting out template decls

	* ACU_Term.cc: try commenting out template decls
	
===================================Maude 1.0.2 released=======================================
===================================Maude 1.0.1 released=======================================

1999-02-18  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_RhsAutomaton.cc (buildArguments): for() changed to
	do-while()
	
===================================VectorExperiment==========================================

1999-01-19  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_LhsCompiler0.cc (tryToMakeAlienAlienLhsAutomaton): fixed
	nasty long running bug where we were not dealing correctly with
	UNDECIDED from Term::subsumes()

1999-01-16  Steven Eker  <eker@goo.csl.sri.com>

	* ACU_LhsAutomaton.hh (class ACU_LhsAutomaton): changed
	matchAtTop, inErrorSort and collapsePossible to Bool to save memory
	(class ACU_LhsAutomaton): changed matchStrategy to Byte to save memory

	* ACU_Term.hh (class ACU_Term): made
	Pair::abstractionVariableIndex a short to save memory
	
===================================Engine46==================================================

Tue Dec  8 10:48:45 1998  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_Term.cc (Term): fixed nasty bug where we were not copying
	multiplicity correctly
	
===================================Engine44==================================================

Fri Nov  6 15:30:44 1998  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_Term.cc (deepCopy): -> deepCopy2()

	* ACU_Term.hh (class ACU_Term): deepCopy() -> deepCopy2()
	
===================================Engine43==================================================

Wed Oct 28 14:41:53 1998  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_AlienAlienLhsAutomaton.cc (match): fixed nasty bug in
	extension setting code: e->setUnmatched(i, m); becomes
	e->setUnmatched(k, m);

Thu Oct  8 13:41:45 1998  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_Term.cc (compareArguments): (DagNode* version) added
	const_cast
	(compareArguments): (DagNode* version) removed const_cast, added
	const
	(compareArguments): (Term* version) added const

	* ACU_Term.hh: added #include "ACU_Symbol.hh" so that we can down
	cast everwhere in symbol()

Fri Oct  2 11:20:43 1998  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_Matcher.cc (multiplicityChecks): added SPEED_HACKS
	(multiplicityChecks): rewritten; simpler and much faster in the
	maxPatternMultiplicity > 1 fail case at the cost of being slightly
	slower (or maybe not?) in the success case. When
	maxPatternMultiplicity > 1 failure seems to be _much_ more
	likely.
	
===================================Engine41==================================================

Tue Sep 22 14:52:16 1998  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_Symbol.cc (computeBaseSort): use lastIndex heuristic in
	uniform sort structure case

	* ACU_CollectorLhsAutomaton.cc (collect): put collectorSort
	pointer into local variable to avoid reload; Use lastIndex
	heuristic to try and avoid sort comparisons; use leq(int, Sort*)
	instead of DagNode::Sort* where neccessary

Fri Sep 18 11:28:08 1998  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_DagNode.cc (overwriteWithClone): use setSortIndex()
	(makeClone): use setSortIndex()

	* ACU_Symbol.cc (computeBaseSort): rewritten using setSortIndex(),
	DagNode::leq(), traverse() and lookupSortIndex()

Thu Sep 17 18:17:18 1998  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_VarLhsAutomaton.cc (match): use DagNode::leq() (2 places)

	* ACU_NonLinearLhsAutomaton.cc (match): use DagNode::leq() (5
	places)

	* ACU_Matcher.cc (forcedLoneVariableCase): use DagNode::leq()

	* ACU_GreedyMatcher.cc (greedyPureMatch): use DagNode::leq() (2
	places)
	(greedyPureMatch): use leq(Sort*,Sort*)

	* ACU_CollectorLhsAutomaton.cc (collect): use DagNode::leq() (5
	places)

Fri Sep 11 17:26:33 1998  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_Subproblem.cc (solveVariables): use new checkSort() convention

	* ACU_Matcher.cc (forcedLoneVariableCase): use new checkSort()
	convention

	* ACU_Symbol.cc (computeBaseSort): use <=(DagNode*,Sort&) (1 place)

	* ACU_VarLhsAutomaton.cc (match): use <=(DagNode*,Sort&) (2
	places)

	* ACU_NonLinearLhsAutomaton.cc (match): use <=(DagNode*,Sort&)
	(5 places)

	* ACU_DagNode.cc (matchVariableWithExtension): pass sort rather
	than code to addTopVariable()

	* ACU_Matcher.cc (forcedLoneVariableCase): use <=(DagNode*,Sort&)
	(fullMatch): pass sort rather than code to addTopVariable()

	* ACU_GreedyMatcher.cc (greedyPureMatch): use <=(DagNode*,Sort&)
	(2 places) and <=(Sort&,Sort&)

	* ACU_CollectorLhsAutomaton.cc (collect): use <=(DagNode*,Sort&)
	(5 places)

	* ACU_Subproblem.cc (addTopVariable): store sort rather than sortCode
	(solveVariables): temporary hack: pass sort->code() to checkSort()
	(dump): sort rather than sortCode

	* ACU_Subproblem.hh (class ACU_Subproblem): struct TopVariable now
	has sort rather than sortCode; addTopVariable() decl updated

Wed Sep  9 11:52:44 1998  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_Symbol.cc (compileOpDeclarations): call
	commutativeSortCompletion() before Symbol::compileOpDeclarations()
	due to new implementation
	
===================================Engine40==================================================

Mon Jul 20 19:35:25 1998  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_Term.hh (class ACU_Term): added decl for new ctor

	* ACU_Term.cc (deepCopy): added
	(ACU_Term): added new ctor

	* ACU_Term.hh (class ACU_Term): added decl for deepCopy()
	
===================================Engine39==================================================

Wed Jun 10 11:57:08 1998  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_Symbol.cc (postInterSymbolPass): added to do identity stuff
	(compileOpDeclarations): don't do identity stuff here anymore

	* ACU_Term.hh (class ACU_Term): updated
	normalizeAliensAndFlatten() and normalize() decls

	* ACU_Term.cc: IntSet -> NatSet
	(normalize): go back to getIdentity(); set changed flag if
	normalization made any changes to term; clear changed otherwise
	(normalizeAliensAndFlatten): return flag to say wether we changed term

	* ACU_LhsCompiler3.cc: IntSet -> NatSet

	* ACU_LhsCompiler2.cc: IntSet -> NatSet

	* ACU_LhsCompiler1.cc: IntSet -> NatSet

	* ACU_LhsCompiler0.cc: IntSet -> NatSet

	* ACU_Term.hh: IntSet -> NatSet
	
===================================Engine38==================================================

Wed Jun  3 16:29:33 1998  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_Term.cc (normalize): use earlyGetIdentity()
	
===================================Engine37==================================================

Fri Mar  6 17:22:37 1998  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_DagOperations.cc (eliminateSubject): fixed nasty bug  - test
	should be identity != 0 && identity->equal(target) and we had ||

Tue Feb 24 11:10:10 1998  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_Matcher.cc (eliminateBoundVariables): simplify now that
	eliminateSubject() handle identity

	* ACU_DagOperations.cc (eliminateSubject): handle identity; this
	fixes a serious bug in ACU_Subproblem::extractDiophantineSystem()
	which assumed we were

	* ACU_Subproblem.cc (dump): added
	(dump): dump local bindings
	(solveVariables): fixed serious bug - in the trivial Diophantine
	system case where findFirst is false we must unbind any variables
	we bound to the identity the first time around before returning false.

	* ACU_Subproblem.hh (class ACU_Subproblem): added decl for dump()

Fri Feb 20 17:27:13 1998  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_DagNode.cc (stackArguments): only stack arguments that are
	not flagged as unstackable
	
===================================Engine36==================================================

Sat Feb 14 14:45:02 1998  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_LhsAutomaton.cc (ACU_LhsAutomaton): need to delete
	uniqueCollapseAutomaton and abstraction automata

Thu Feb 12 17:50:45 1998  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_NGA_LhsAutomaton.cc (~ACU_NGA_LhsAutomaton): added

	* ACU_NGA_LhsAutomaton.hh (class ACU_NGA_LhsAutomaton): added decl
	for ~ACU_NGA_LhsAutomaton()

	* ACU_AlienAlienLhsAutomaton.cc (~ACU_AlienAlienLhsAutomaton): add

	* ACU_AlienAlienLhsAutomaton.hh (class
	ACU_AlienAlienLhsAutomaton): added decl for
	~ACU_AlienAlienLhsAutomaton()

	* ACU_LhsAutomaton.cc (ACU_LhsAutomaton): added

	* ACU_LhsAutomaton.hh (class ACU_LhsAutomaton): added decl for
	~ACU_LhsAutomaton()

Wed Feb 11 16:46:29 1998  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_VarLhsAutomaton.cc (match): compare() != 0 replaced by
	!equal()

	* ACU_Term.cc (normalize): compare() == 0 replaced by equal() (2
	places)

	* ACU_Matcher.cc (eliminateBoundVariables): compare() != 0
	replaced by !equal()

	* ACU_GndLhsAutomaton.cc (match): compare() != 0 replaced by
	!equal()

	* ACU_CollapseMatcher.cc (uniqueCollapseMatch): compare() != 0
	replaced by !equal()
	(multiwayCollapseMatch): compare() != 0 replaced by !equal()
	(multiwayCollapseMatch): compare() == 0 replaced by equal() (2
	places)

	* ACU_NGA_LhsAutomaton.cc (match): use delete rather than
	calling deepSelfDestruct()

	* ACU_Matcher.cc (buildBipartiteGraph): use delete rather than
	calling deepSelfDestruct()

	* ACU_GreedyMatcher.cc (greedyMatch): use delete rather than
	calling deepSelfDestruct()

	* ACU_AlienAlienLhsAutomaton.cc (match): use delete rather than
	calling deepSelfDestruct()

	* ACU_Subproblem.hh (class ACU_Subproblem): deleted decl for
	deepSelfDestruct()

	* ACU_Subproblem.cc (deepSelfDestruct): deleted
	(~ACU_Subproblem): inserted bulk of code from old
	deepSelfDestruct(); use delete rather than calling
	deepSelfDestruct()
	
===================================Engine35==================================================

Fri Jan 16 18:19:12 1998  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_Term.cc (insertAbstractionVariables): changed
	AdvisoryCheck() to DebugAdvisoryCheck()

Wed Dec 24 15:34:20 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_LhsAutomaton.cc (dump): dump uniqueCollapseAutomaton if it exists

Tue Dec 23 12:38:55 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_LhsAutomaton.cc (dump): don't try to print name of an
	abstraction variable

	* ACU_LhsCompiler1.cc (compileLhs2): use greedySafe()

	* ACU_LhsCompiler0.cc (tryToMakeAlienAlienLhsAutomaton): use greedySafe()
	(tryToMakeCollectorLhsAutomaton): use greedySafe()

Thu Dec 18 18:01:52 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_LhsAutomaton.cc (addTopVariable): use Term::takeIdentity()

	* ACU_LhsCompiler0.cc (tryToMakeNonLinearLhsAutomaton): use
	Term::takeIdentity()
	(tryToMakeCollectorLhsAutomaton): use Term::takeIdentity()

Wed Dec 17 12:03:01 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_NonLinearLhsAutomaton.cc (match): check to see that we
	actually have a match before allocating ACU_DagNode in non ext
	case; the space for the ACU_DagNode can be very big and this case
	is likely to fail.

	* ACU_NonLinearLhsAutomaton.hh (class ACU_NonLinearLhsAutomaton):
	made varIndex, multiplicity, varSort, unitSort const

Tue Dec 16 11:52:36 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_Term.hh (class ACU_Term): added decl for tryToMakeNonLinearLhsAutomaton()

	* ACU_LhsCompiler0.cc (compileLhs): major rewrite and simplification
	(tryToMakeNonLinearLhsAutomaton): added

	* ACU_NonLinearLhsAutomaton.cc (match): handle case where variable
	is bound
	(dump): call HeuristicLhsAutomaton::dump()

	* ACU_NonLinearLhsAutomaton.hh (class ACU_NonLinearLhsAutomaton):
	derive from HeuristicLhsAutomaton

	* ACU_AlienAlienLhsAutomaton.cc (complete): deleted
	(match): use fullMatch()
	(dump): call HeuristicLhsAutomaton::dump()

	* ACU_AlienAlienLhsAutomaton.hh (class
	ACU_AlienAlienLhsAutomaton): derive from HeuristicLhsAutomaton;
	deleted decl for complete(); data member fullAutomaton;

	* ACU_CollectorLhsAutomaton.cc (dump): call HeuristicLhsAutomaton::dump()
	(complete): deleted

	* ACU_CollectorLhsAutomaton.hh (class ACU_CollectorLhsAutomaton):
	derive from HeuristicLhsAutomaton
	(class ACU_CollectorLhsAutomaton): deleted decls for complete()
	and fullMatch()
	(fullMatch): deleted
	(class ACU_CollectorLhsAutomaton): deleted data member fullAutomaton

	* ACU_LhsCompiler0.cc (compileLhs): insert index of variable into
	boundUniquely when making a ACU_NonLinearLhsAutomaton

	* ACU_NonLinearLhsAutomaton.cc (match): fixed bug where we were
	forgetting to increment p when building new ACU_DagNode

	* ACU_LhsCompiler0.cc (compileLhs): added code to make
	ACU_NonLinearLhsAutomaton where appropriate

Mon Dec 15 18:54:20 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_NonLinearLhsAutomaton.cc: created

	* ACU_NonLinearLhsAutomaton.hh (class ACU_NonLinearLhsAutomaton):
	created
	
===================================Engine34==================================================

Thu Dec 11 18:24:11 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_Subproblem.cc (solveVariables): check that we actually have
	a sort before calling d->setReduced() since d->checkSort() is not
	guarenteed to leave a sort behind (in the presence of sort constraints).

Fri Dec  5 11:23:05 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_DagOperations.cc (eliminateArgument): code cleaning

	* ACU_Symbol.cc (eqRewrite): optimized use of nrArgs
	(compileOpDeclarations): only call leftIdentitySortCheck() and
	rightIdentitySortCheck() if we actually have an identity

	* ACU_Symbol.hh (class ACU_Symbol): deleted utilityBuffer static
	class member decl

	* ACU_Symbol.cc (finalizeSortInfo): deleted
	(compileOpDeclarations): call leftIdentitySortCheck() and
	rightIdentitySortCheck()
	deleted utilityBuffer static class member
	(computeBaseSort): use local static sortIndexBuffer in place of
	utilityBuffer

	* ACU_Symbol.hh (class ACU_Symbol): deleted finalizeSortInfo() decl

Thu Dec  4 12:52:46 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_Term.cc (compareArguments): compare multiplicity before
	actaul argument (dagNode version)
	(compareArguments): compare multiplicity before
	actaul argument (term version)

	* ACU_DagNode.cc (compareArguments): compare multiplicity before
	actaul argument; this may avoid comparison of argument in some cases.

	* ACU_Symbol.cc (ACU_Symbol): deleted inert arg

	* ACU_Symbol.hh (class ACU_Symbol): deleted inert
	arg from ctor decl

Tue Dec  2 16:40:08 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_Symbol.cc (copyAndReduceSubterms): use DagNode::copyAndReduce()

Mon Dec  1 11:33:38 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_Symbol.cc (eqRewrite): use getPermuteStrategy() (*3)

	* ACU_Term.cc (markEagerArguments): use getPermuteStrategy()
	(findEagerVariables): use getPermuteStrategy()

	* ACU_Symbol.cc (ACU_Symbol): PermuteSymbol -> AssociativeSymbol
	(eqRewrite): PermuteSymbol -> AssociativeSymbol (*3)

	* ACU_Term.cc (findEagerVariables): PermuteSymbol -> BinarySymbol (*3)
	(markEagerArguments): PermuteSymbol -> BinarySymbol

	* ACU_LhsCompiler0.cc (tryToMakeCollectorLhsAutomaton): PermuteSymbol ->
	AssociativeSymbol (*2)

	* ACU_LhsAutomaton.cc (addAbstractionVariable): PermuteSymbol ->
	AssociativeSymbol

	* ACU_GreedyMatcher.cc (greedyPureMatch): PermuteSymbol ->
	AssociativeSymbol (*4)

	* ACU_DagOperations.cc (eliminateArgument): use getPermuteStrategy()

	* ACU_DagNode.cc (copyEagerUptoReduced2): use getPermuteStrategy()

	* ACU_Symbol.hh (class ACU_Symbol): PermuteSymbol ->
	AssociativeSymbol

	* ACU_LhsAutomaton.hh (class ACU_LhsAutomaton): PermuteSymbol ->
	AssociativeSymbol

Mon Nov 24 11:09:15 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_AlienAlienLhsAutomaton.cc (dump): implemented

	* ACU_DagNode.hh (class ACU_DagNode): ACU_FastLhsAutomaton no
	longer exists and hence is no longer a friend

	* ACU_RhsAutomaton.cc (buildAliens): deleted
	(dump): implemented

	* ACU_RhsAutomaton.hh (class ACU_RhsAutomaton): deleted aliens
	data member
	(addAlien): deleted

	* ACU_Term.hh (class ACU_Term): updated member function declarations

	* ACU_LhsCompiler0.cc (compileLhs): rewrutten
	(tryToMakeFastAutomation2): renamed to
	tryToMakeAlienAlienLhsAutomaton() 
	(tryToMakeFastAutomaton): renamed to
	tryToMakeCollectorLhsAutomaton() 
	(tryToMakeCollectorLhsAutomaton): rewrittten to use new derived classes

	* ACU_GndLhsAutomaton.cc: created

	* ACU_GndLhsAutomaton.hh (class ACU_GndLhsAutomaton): created

	* ACU_DagNode.hh (class ACU_DagNode): ACU_VarLhsAutomaton becomes
	a friend
	(class ACU_DagNode): ACU_GndLhsAutomaton becomes a friend

	* ACU_VarLhsAutomaton.hh (class ACU_VarLhsAutomaton): created

	* ACU_VarLhsAutomaton.cc: created

	* ACU_DagNode.hh (class ACU_DagNode): ACU_NGA_LhsAutomaton becomes
	a friend

	* ACU_CollectorLhsAutomaton.cc (complete): added
	(dump): now dump fullAutomaton

	* ACU_CollectorLhsAutomaton.hh (fullMatch): added

	* ACU_NGA_LhsAutomaton.hh (class ACU_NGA_LhsAutomaton): created

	* ACU_NGA_LhsAutomaton.cc: created

Sun Nov 23 17:27:37 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_DagNode.hh (class ACU_DagNode): ACU_CollectorLhsAutomaton
	becomes a friend

	* ACU_FastLhsAutomaton.cc (dump): rewritten as a temporary hack
	9this class will soon be split 3 ways)

	* ACU_FastLhsAutomaton.hh (class ACU_FastLhsAutomaton): updated
	dump() decl

	* ACU_AlienAlienLhsAutomaton.hh (class
	ACU_AlienAlienLhsAutomaton): updated dump() decl

	* ACU_LhsAutomaton.cc (dump): rewritten

	* ACU_RhsAutomaton.hh (class ACU_RhsAutomaton): updated dump() decl

	* ACU_LhsAutomaton.hh (class ACU_LhsAutomaton): updated dump() decl

	* ACU_CollectorLhsAutomaton.cc: created from ACU_FastLhsAutomaton.cc

	* ACU_CollectorLhsAutomaton.hh: created from
	ACU_FastLhsAutomaton.hh
	
===================================Engine33==================================================

Fri Nov 21 14:28:50 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_DagNormalization.cc (extensionNormalizeAtTop): added

	* ACU_Symbol.cc (eqRewrite): have special handling for case when
	normalizationStatus == ACU_DagNode::EXTENSION

	* ACU_DagNode.cc (partialReplace): use setNormalizationStatus()

	* ACU_Subproblem.cc (solveVariables): use setNormalizationStatus()

	* ACU_GreedyMatcher.cc (greedyPureMatch): use setNormalizationStatus()

	* ACU_Matcher.cc (forcedLoneVariableCase): use setNormalizationStatus()

	* ACU_FastLhsAutomaton.cc (collect): use setNormalizationStatus()

	* ACU_DagNode.hh (ACU_DagNode): set theory byte to 0

	* ACU_Symbol.cc (computeBaseSort): use getNormalizationStatus()
	(eqRewrite): use getNormalizationStatus() (3 times)

	* ACU_DagNode.hh (clearShortCircuit): deleted
	(setShortCircuit): deleted
	(getShortCircuit): deleted
	(getNormalizationStatus): added
	(setNormalizationStatus): added

	* ACU_DagNode.cc (partialReplace): made and unmade change to
	remove implicit flattening. The advantage of not implicitly
	flattening is that we don't mix sorted reduced stuff with unsorted
	undeduced stuff and thereby defeat are fast normalization. The
	problem is that we need an extra dag node, more match attempts and
	the new "not in error sort" semantics of the shortCircuit flag in
	unsafe here since the extension part could be in the error sort.

Thu Nov 20 11:58:34 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_ExtensionInfo.hh (reset): added; allows extensionInfo to be
	prepared for use without wasting time clearing it.

	* ACU_AlienAlienLhsAutomaton.cc (match): put automata pointers into
	local variable to avoid gcc generating register reloads after
	function calls. Use ACU_ExtensionInfo::reset().

	* ACU_LhsCompiler0.cc (tryToMakeFastAutomation2): fixed bug where
	we were compile same t1 twice and t2 not at all

	* ACU_AlienAlienLhsAutomaton.cc (match): handle cases where
	first/second symbol does not occcur in subject
	(match): fixed bug where we using wrong local substitution in 2nd match

	* ACU_LhsCompiler0.cc (tryToMakeFastAutomation2): added missing
	return for AlienAlien case

	* ACU_DagNode.hh (class ACU_DagNode): class
	ACU_AlienAlienLhsAutomaton becomes a friend

	* ACU_AlienAlienLhsAutomaton.hh (class ACU_AlienAlienLhsAutomaton): created

	* ACU_AlienAlienLhsAutomaton.cc (ACU_AlienAlienLhsAutomaton): created

Tue Nov 18 18:25:08 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_Term.cc (dump): added
	(dumpArguments): deleted

	* ACU_Term.hh (class ACU_Term): dumpArguments() decl becomes dump()

	* ACU_Term.cc (dumpArguments): removed const; pass variableInfo by
	ref; switch varableInfo, indentLevel args

	* ACU_Term.hh (class ACU_Term): dumpArguments() decl now passes
	variableInfo by ref; removed const; switch varableInfo,
	indentLevel args

Mon Nov 17 11:07:23 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_Subproblem.cc (computeAssignment): don't pass shortCircuit
	argument to ACU_DagNode()
	(solveVariables): setShortCircuit()

	* ACU_Matcher.cc (forcedLoneVariableCase): call setShortCircuit()

	* ACU_GreedyMatcher.cc (greedyPureMatch): call setShortCircuit()

	* ACU_FastLhsAutomaton.cc (collect): call setShortCircuit()

	* ACU_Symbol.cc (eqRewrite): use getShortCircuit() (three places)

	* ACU_DagNode.cc (partialReplace): call clearShortCircuit()

	* ACU_DagNode.hh (class ACU_DagNode): removed shortCircuit arg from
	ctor
	(class ACU_DagNode): added decls for getShortCircuit() and
	setShortCircuit() and clearShortCircuit()
	(class ACU_DagNode): deleted shortCircuit data member
	(ACU_DagNode): non longer intialize shortCircuit
	(setShortCircuit): added
	(getShortCircuit): added
	(clearShortCircuit): added

Fri Nov 14 10:20:07 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_LhsAutomaton.cc (dump): dump collapsePossible

	* ACU_FastLhsAutomaton.cc (collect): added speed hack
	(dump): implemented

	* ACU_LhsCompiler0.cc: don't use fast automaton if we're in error
	sort and we have extension

	* ACU_FastLhsAutomaton.cc (collect): hand optimized

	* ACU_LhsAutomaton.hh (class ACU_LhsAutomaton): all todays changes
	unmade as they made things slower 

	* ACU_Matcher.cc: all todays changes unmade as they made things slower

	* ACU_LhsAutomaton.hh (class ACU_LhsAutomaton): data memeber
	totalMultiplicity deleted
	(class ACU_LhsAutomaton): updated multiplicityChecks() decl

	* ACU_Matcher.cc (multiplicityChecks): rewritten; first case now
	just does copying without multiplicity checks in the case where
	they will all trvially succeed. Second case now has early failure
	when totalSubjectMultiplicity > totalUpperBound
	(multiplicityChecks): rewritten; now sets extensionInfo upperBound
	(match): pass extensionInfo to multiplicityChecks(); don't set
	extensionInfo upperBound

	* ACU_FastLhsAutomaton.cc (ACU_FastLhsAutomaton): changed
	stripperTopSymbol to stripperSymbol to avoid confusion with data member
	(match): make sure we actually bind stripper variable
	(match): bind collector variable in local rather than solution so
	it does not get overwritten when we copy local into solution

	* ACU_LhsCompiler0.cc (tryToMakeFastAutomation): pass
	!(collapseSymbols().empty()) for collapsePossible (2 places)

Thu Nov 13 16:11:00 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_LhsCompiler0.cc: created

	* ACU_Term.hh (class ACU_Term): added decl for compileLhs2()

	* ACU_LhsCompiler1.cc (compileLhs2): created from old
	compileLhs(); now returns ACU_LhsAutomaton*

	* ACU_DagNode.hh (class ACU_DagNode): ACU_FastLhsAutomaton becomes
	a friend

	* ACU_FastLhsAutomaton.hh (class ACU_FastLhsAutomaton): created

	* ACU_FastLhsAutomaton.cc: created
	
===================================Engine32==================================================

Fri Oct 31 16:56:23 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_CollapseMatcher.cc (multiwayCollapseMatch): removed buggy
	optimization where we were binding variables to identity in
	solution after they had been considered for match against whole
	subject; the problem is that solution gets returned to caller with
	these not always correct bindings
	(multiwayCollapseMatch): make use of the faxt that all variables
	with multiplicity > 1 will be bound to dentity once we reach the
	disjuction loop; use DisjunctiveSubproblemAccumulator to simplify code.
	(multiwayCollapseMatch): eliminated first flag by using empty()

Wed Oct 29 10:30:51 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_DagNode.cc (matchVariableWithExtension): call
	extensionInfo->setValidAfterMatch(false)

	* ACU_CollapseMatcher.cc (multiwayCollapseMatch): don't call
	extensionInfo->clear()
	(multiwayCollapseMatch): use extensionInfo->validAfterMatch()
	(multiwayCollapseMatch): use
	extensionInfo->setValidAfterMatch(false) in place of extensionInfo->clear()
	(multiwayCollapseMatch): in the case where the subject is our
	identity we fix a bug by checking for extension info and calling
	extensionInfo->setValidAfterMatch(true) and
	extensionInfo->setMatchedWhole(true) if so. Previously we didn't
	worry about extension with the result that it was never set,
	allowing an uninitialized data read in partialConstruct() for example.
	(multiwayCollapseMatch): non viable variable that are unbound are
	bound to identity at the outset (that is unbound variables that
	have multiplicity > 1). The case where nrViableVariables == 0
	contained a bug since we could still get a match if extension was
	present. The case where nrViableVariables == 1 clean up now we
	know that all other variables are bound to identity.

	* ACU_Subproblem.cc (fillOutExtensionInfo): use setMatchedWhole()
	in place of setWholeFlag() (2 places)
	(solveVariables): use setMatchedWhole() in place of setWholeFlag()

	* ACU_GreedyMatcher.cc (greedyPureMatch): call
	setValidAfterMatch(true) if we fill out the extension info

	* ACU_Matcher.cc (fullMatch): call setValidAfterMatch(false) since
	extension info will not be valid until solve phase

	* ACU_ExtensionInfo.cc (makeClone): use setValidAfterMatch(),
	validAfterMatch() and setMatchedWhole()
	(copy): use setValidAfterMatch(),
	validAfterMatch() and setMatchedWhole()

Tue Oct 28 10:19:21 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_CollapseMatcher.cc (multiwayCollapseMatch): clear extension
	information if it exists before each call to matchVariable; only
	save extensionInfo in SubproblemDisjunction in the case where it
	is valid (regardless of whether subproblem == 0 because we can
	have the case where extensionInfo is valid but subproblem != 0);
	Before exiting with true we clear any old extension info that
	might exist be cause it will now be invalid (having been saved on
	one of the disjuction paths it cannot be globally valid).

Mon Oct 27 11:43:56 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_CollapseMatcher.cc (multiwayCollapseMatch): save
	extensionInfo in SubproblemDisjunction in the case where subproblem == 0

	* ACU_ExtensionInfo.hh (class ACU_ExtensionInfo): subject made non
	const in order to do copy()

	* ACU_ExtensionInfo.cc (makeClone): added
	(copy): added

	* ACU_ExtensionInfo.hh (class ACU_ExtensionInfo): added decls for
	makeClone() and copy()

Fri Oct 24 13:07:30 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_Subproblem.cc (solveVariables): use
	ExtensionInfo::buildMatchedPortion() and DagNode::inErrorSort()
	instead of matchedPortionOK(); call fillOutExtensionInfo() first
	(matchedPortionOK): deleted

	* ACU_Subproblem.hh (class ACU_Subproblem): deleted decl for
	matchedPortionOK();

	* ACU_CollapseMatcher.cc (multiwayCollapseMatch): use
	EqualitySubproblem instead of ExclusionSubproblem

	* ACU_DagNode.hh (class ACU_DagNode): class ACU_ExtensionInfo is
	now a friend

	* ACU_Symbol.cc (ruleRewrite): switched to new ACU_ExtensionInfo convention
	(eqRewrite): switched to new ACU_ExtensionInfo convention (3 places)

	* ACU_DagNode.cc (makeExtensionInfo): switched to new
	ACU_ExtensionInfo convention

	* ACU_Theory.cc: deleted

	* ACU_ExtensionInfo.cc: created

	* ACU_ExtensionInfo.hh (ACU_ExtensionInfo): ctor now takes subject
	rather than nrArgs; added decl for buildMatchedPortion()
	(clear): use subject data member
	(ACU_ExtensionInfo): store subject arg in data member

Tue Oct 21 12:23:04 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_CollapseMatcher.cc (multiwayCollapseMatch): add exclusion
	subproblems to eliminate duplicate solutions in the case that the
	subject matches out identity with extension.

	* ACU_Term.cc (dagify2): switched to new convention

	* ACU_Term.hh (class ACU_Term): switched dagify2() decl to new convention

Wed Oct 15 17:17:16 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_Subproblem.cc (solveVariables): use BinarySymbol::getIdentityDag()
	(2 places)
	(solveVariables): delete identityDag local variable

	* ACU_GreedyMatcher.cc (greedyPureMatch): use BinarySymbol::getIdentityDag()
	(greedyPureMatch): delete identityDag local variable

	* ACU_Matcher.cc (match): use BinarySymbol::getIdentityDag()

	* ACU_LhsAutomaton.hh (class ACU_LhsAutomaton): delete identityDag
	arg from bindUnboundVariablesToIdentity()

	* ACU_CollapseMatcher.cc (uniqueCollapseMatch): use BinarySymbol::getIdentityDag()
	(bindUnboundVariablesToIdentity): use
	BinarySymbol::getIdentityDag(); remove identityDag arg
	(multiwayCollapseMatch): use BinarySymbol::getIdentityDag()

	* ACU_LhsCompiler1.cc (analyseConstraintPropagation): use VariableTerm::dynamicCast()
	(compileLhs): use VariableTerm::dynamicCast()

	* ACU_Term.cc (mightCollapseToOurSymbol): deleted
	(mightMatchOurIdentity): deleted
	(analyseCollapses): use BinarySymbol::mightMatchOurIdentity()
	(insertAbstractionVariables): use BinarySymbol::mightMatchOurIdentity()
	(insertAbstractionVariables): use PermuteSymbol::mightCollapseToOurSymbol()
	(compileRhs): use VariableTerm::dynamicCast()
	(insertAbstractionVariables): use VariableTerm::dynamicCast()

	* ACU_Term.hh (class ACU_Term): deleted decls for
	mightCollapseToOurSymbol() and mightMatchOurIdentity()

	* ACU_Symbol.cc (~ACU_Symbol): deleted
	(compileOpDeclarations): use BinarySymbol::processIdentity()
	(eqRewrite): use getIdentity() (2 places)
	(computeTrueSort): use getIdentity()

	* ACU_Symbol.hh (class ACU_Symbol): delete dtor decl

	* ACU_Symbol.cc (ACU_Symbol): rewritten to use new PermuteSymbol conventions

	* ACU_Symbol.hh (class ACU_Symbol): removed constructor arg from
	ctor; deleted decls for getIdentity() and makeIdentityDag();
	(class ACU_Symbol): deleted identity, identityAutomaton and
	identitySubstitution data members
	(getIdentity): deleted
	(makeIdentityDag): deleted

Mon Oct 13 10:36:57 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_Term.cc (mightCollapseToOurSymbol): added
	(mightMatchOurIdentity): added
	(analyseCollapses): added
	(insertAbstractionVariables): added
	(determineCollapseSymbols): deleted

	* ACU_Term.hh (class ACU_Term): added decls for analyseCollapses()
	and insertAbstractionVariables(); delete decl for determineCollapseSymbols()

	* ACU_LhsAutomaton.cc (dump): index2Symbol() -> index2Variable()

	* ACU_LhsAutomaton.hh (class ACU_LhsAutomaton): VariableIndex -> VariableInfo

	* ACU_LhsAutomaton.cc (dump): VariableIndex -> VariableInfo

	* ACU_Term.cc (dumpArguments): VariableIndex -> VariableInfo
	(determineCollapseSymbols): VariableIndex -> VariableInfo
	(dumpArguments): VariableIndex -> VariableInfo

	* ACU_Term.hh (class ACU_Term): VariableIndex -> VariableInfo

	* ACU_Symbol.cc (compileOpDeclarations): VariableIndex ->
	VariableInfo
	
===================================Engine30==================================================

Tue Oct  7 15:32:51 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_Symbol.hh (class ACU_Symbol): added decl for makeDagNode()

	* ACU_Symbol.cc (makeDagNode): added

Fri Oct  3 19:26:11 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_Symbol.cc (compileOpDeclarations): DataSet -> TermSet

	* ACU_Term.cc (compileRhs): DataSet -> TermSet
	(dagify2): DataSet -> TermSet

	* ACU_Term.hh (class ACU_Term): DataSet -> TermSet
	
===================================Engine29==================================================

Thu Oct  2 17:43:48 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_Symbol.cc (compileOpDeclarations): pass DataSet to compileRhs()

	* ACU_Term.hh (class ACU_Term): updated compileRhs() decl

	* ACU_Term.cc (compileRhs): adapted to use DataSet& compiled

Tue Sep 30 12:18:57 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_Term.hh (class ACU_Term): dagify() decl changed to dagify2()

	* ACU_Term.cc (normalize): now compute hash values
	(dagify2): adapted from dagify()

Thu Sep 25 16:38:20 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_Term.cc (determineCollapseSymbols): use getOpDeclarations()

	* ACU_Symbol.cc (specificRewrite): deleted

	* ACU_Symbol.hh (class ACU_Symbol): deleted decl for
	specificRewrite()
	
===================================Engine28==================================================

Mon Aug 25 12:11:34 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_Symbol.cc (eqRewrite): fixed a bug where we could collapse
	to an unreduced subterm and stop rewriting at this node. We now
	return true in this case to force rewriting to continue.

Tue Aug 19 15:27:21 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_DagNode.hh (nrArgs): added
	(getArgument): added
	(getMultiplicity): added
	(class ACU_DagNode): added decl for nrArgs(), getArgument(int i),
	getMultiplicity(int i). This provide a fast interface to the
	argument list for non ACU_Theory code that is ACU_Theory aware
	(maybe classes derived from ACU_Symbol).

Fri Jul 25 18:04:23 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_DagNode.cc (partialReplace): removed Assert(getSortIndex() ==
	Sort::SORT_UNKNOWN, cerr << "shouldn't have valid sort"); since if
	node was original created by matcher it may well have valid sort

Thu Jul 24 11:20:50 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_GreedyMatcher.cc (greedyPureMatch): optimized vector
	accesses for assignment building
	(greedyPureMatch): optimized inner loop for assigning unassigned subjects

	* ACU_Subproblem.cc (computeAssignment): pass shortCircuit =
	true to ACU_DagNode()

	* ACU_GreedyMatcher.cc (greedyPureMatch): pass shortCircuit =
	true to ACU_DagNode()

	* ACU_Matcher.cc (forcedLoneVariableCase): pass shortCircuit =
	true to ACU_DagNode()

	* ACU_Symbol.cc (eqRewrite): added s->eliminateArgument(identity)
	calls after new normalizeAtTop() calls
	(eqRewrite): rewritten from scatch to make use of short circuit

	* ACU_DagNode.cc (partialReplace): clear shortCircuit flag

	* ACU_DagNode.hh (ACU_DagNode): set shortCircuit flag

	* ACU_Symbol.cc (eqRewrite): added normalizeAtTop() calls after
	sort computation for LAZY and SEMI_EAGER cases; this fixes a bug
	introduced by just-in-time normalization

	* ACU_DagNode.hh (class ACU_DagNode): added shortCircuit data
	member; the idea is to set this when an ACU_DagNode is created in
	the matcher cut down need for normalization checking

Wed Jul 23 11:50:27 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_DagNode.cc (partialReplace): added call to repudiateSortInfo()

	* ACU_Term.cc (normalize): added full flag
	(normalize): don't call normalizeAliensAndFlatten() if full = false
	(normalizeAliensAndFlatten): pass full = true to normalize()

	* ACU_Term.hh (class ACU_Term): added full flag to normalize

	* ACU_Symbol.cc (ACU_Symbol): pass full = true to normalize()
	(compileOpDeclarations): deleted superfluous normalization call

Mon Jul 21 10:24:23 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_RhsAutomaton.hh (class ACU_RhsAutomaton): updated
	buildArguments() decl

	* ACU_RhsAutomaton.cc (buildArguments): take argArray rather than node

	* ACU_Symbol.cc (computeTrueSort): now do normalization

	* ACU_DagNode.hh (class ACU_DagNode): deleted
	normalizeEagerUptoReduced2() and nonEagerInsert() decls

	* ACU_DagNode.cc (normalizeEagerUptoReduced2): deleted
	(partialReplace): no longer attempt to normalize node
	(partialConstruct): no longer attempt to normalize node
	(copyWithReplacement): no longer attempt to normalize node
	(nonEagerInsert): deleted

	* ACU_Term.cc (compileRhs): no longer pass normalize flag to ACU_RhsAutomaton
	(compileRhs): no longer pass term to addArgument()

	* ACU_RhsAutomaton.cc (ACU_RhsAutomaton): no longer initialize simpleCtor
	(buildArguments): no longer check for reduced args or return bool
	(construct): greatly simplified; no longer attempt normalization
	under any circumstance
	(replace): greatly simplified; no longer attempt normalization
	under any circumstance

	* ACU_RhsAutomaton.hh (class ACU_RhsAutomaton): removed simpleCtor
	member
	(class ACU_RhsAutomaton): changed buildArguments() decl

===================================Engine26b==================================================
	
Fri Jul 18 16:11:45 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_RhsAutomaton.hh (class ACU_RhsAutomaton): (26) updated to
	agree with all the changes below

	* ACU_RhsAutomaton.cc (ACU_RhsAutomaton): (26b) stripped stable stuff;
	deleted normalize arg
	(addArgument): (26b) all stable stuff removed; term arg removed
	(close): (26b) all stable stuff removed
	(calculateFlattening): (26b) all stable stuff removed
	(normalizeBuildArguments): (26b) deleted
	(buildArguments): (26b) created from old fastBuildArguments)
	(calculateFlattening): (26b) deleted
	(buildArguments): (26b) now return allReducedFlag
	(tryToSetReducedFlag): (26b) deleted
	(allArgumentsReduced): (26b) deleted
	(replace): (26b) rewritten
	(construct): (26b) rewritten

	* ACU_RhsAutomaton.hh (class ACU_RhsAutomaton): (26b) stripped
	stable stuff
	(class ACU_RhsAutomaton): (26b) stripped normalize flag
	(class ACU_RhsAutomaton): (26b) removed normalize arg from ctor

	* ACU_DagNode.cc (normalizeEagerUpToReduced2): added
	(nonEagerInsert): use normalizeEagerUpToReduced()

	* ACU_DagNode.hh (class ACU_DagNode): added decl for
	normalizeEagerUpToReduced2()

Thu Jul 17 10:38:22 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_DagNode.hh (class ACU_DagNode): added decl for nonEagerInsert()

	* ACU_DagNode.cc (nonEagerInsert): added
	(partialReplace): rewritten using nonEagerInsert()
	(partialConstruct): rewritten using nonEagerInsert()
	(copyWithReplacement): rewritten using nonEagerInsert()

	* ACU_RhsAutomaton.cc (addArgument): changed criteria for stable
	arg; must
	(1) be stable term;
	(2) not have our top symbol on top (+NEW*)
	(3) not have our identity's top symbol on top (*NEW*)
	(4) have a top symbol greater than that of last stable arg
	Condition (2) is necessary since we will no longer flatten rhs in
	eager context. Condition (3) allows us to restrict search for
	identity to case where we have unstable args.
	(normalizeBuildArguments): code for removing identity elements
	pushed into unstable case

	* ACU_Term.cc (compileRhs): calculate and pass normalize flag to
	ACU_RhsAutomaton()

	* ACU_RhsAutomaton.hh (class ACU_RhsAutomaton): runs -> runsBuffer
	(class ACU_RhsAutomaton): added and changed memebr function decls
	to agree with all the recent changes in ACU_RhsAutomaton.cc

	* ACU_RhsAutomaton.cc (normalizeBuildArguments): created from old
	buildArguments(); now do identity elimination
	(close): runs renamed to runsBuffer
	(replace): rewritten from scratch to be like new construct()
	(ACU_RhsAutomaton): initialize normalize flag

Wed Jul 16 11:41:48 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_RhsAutomaton.cc (construct): fixed bug where we were
	applying tryToSetReducedFlag() to a non ACU dagnode produced by
	eliminateArgument(identity)
	(replace): fix bug similar to above
	(construct): rewritten from scratch to handle building dagNode in
	normalized or denormalized form depending on the circumstances
	(buildAliens): now much simpler; return void
	(allArgumentsReduced): added
	(calculateFlattening): added
	(fastBuildArguments): added
	(tryToSetReducedFlag): simplified

Tue Jul 15 15:33:28 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_RhsAutomaton.cc (ACU_RhsAutomaton): simpleCtor
	initialization simplified

	* ACU_Symbol.cc (ACU_Symbol): added inert arg
	(eqRewrite): inert() call replaced by equationFree() call

	* ACU_Symbol.hh (class ACU_Symbol): added inert arg to ctor
	
=====================================Engine26=================================================
	
Mon Jul 14 10:48:39 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_DagNode.hh (class ACU_DagNode): changed decl for
	sortAndUniquize(); tidied private function decls

	* ACU_DagNormalization.cc (sortAndUniquize): code cleaned; make
	non-static; arg deleted; made local_inline
	(flattenSortAndUniquize): made local_inline
	(normalizeAtTop): deleted arg from sortAndUniquize() call

Fri Jul 11 12:01:09 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_DagNode.hh (class ACU_DagNode): added decl for flattenSortAndUniquize()

	* ACU_DagNormalization.cc: created
	(normalizeAtTop): optimized; now use flattenSortAndUniquize()
	(flattenSortAndUniquize): added

	* ACU_DagOperations.cc: created

	* ACU_DagNode.cc: ACU specific functions split off into
	ACU_DagNormalization.cc and ACU_DagOperations.cc

Wed Jul  9 10:53:22 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_RhsAutomaton.hh (class ACU_RhsAutomaton): added decl for
	tryToSetReducedFlag()

	* ACU_RhsAutomaton.cc (topSymbol): initialize simpleCtor
	(tryToSetReducedFlag): added

	* ACU_RhsAutomaton.hh (class ACU_RhsAutomaton): simpleStor flag added

	* ACU_Subproblem.cc (computeAssignment): added comment to note the
	fact that assigments are built in normal form
	(solveVariables): added topSymbol and buildReducedNodes local
	variables; now set reduced flags on nodes with our top symbol if
	the subject is reduced.

	* ACU_Matcher.cc (forcedLoneVariableCase): set reduced flag on
	created ACU dag node if subject is reduced and new dag node has
	its true sort after sort checkSort()

	* ACU_GreedyMatcher.cc (greedyPureMatch): if the subject is
	reduced and the top symbol is sort constraint free when we build
	assignments using the top symbols we compute their true sort
	(which is equal to their base sort) and set the reduced flag. This
	avoid unnecessary future normalization and matching attempts at
	the cost of a small matching overhead and having the matcher no
	longer oblivious to reduced flags and sort constraints. Ideally
	this optimization should only be done for assignments to variables
	that are "useful"; i.e. that appear in the rhs or condition. At
	some point we should add a "useful" flag to TopVariable or maybe a
	more sophisticated mechanism that would allow optimization of solutions.

Tue Jul  1 10:19:58 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_DagNode.cc (compareArguments): use modified multiset ordering

	* ACU_Term.cc (compareArguments): use modified multiset ordering
	(compareArguments): use modified multiset ordering

	* ACU_DagNode.cc (sortAndUniquize): switched two tests on "r"
	because we now sort in ascending order
	(mergeSortAndUniquize): switched two tests on "r"
	because we now sort in ascending order
	(findFirstOccurrence): switched test on "r" because we now
	sort in ascending order
	(binarySearch): switched test on "r" because we now
	sort in ascending order (DagNode* version)
	(binarySearch): switched test on "r" because we now
	sort in ascending order (Term* version)

Mon Jun 30 16:28:11 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_DagNode.cc (compareArguments): rewritten to do multiset ordering under the
	assumption that args are sorted in ascending order

	* ACU_RhsAutomaton.cc (buildArguments): changed comparison to r >
	0 now that we want to swap args into ascending order
	(addArgument): changed test for adding new stable arg to < 0 since
	stable args will now be in ascending order of symbols

	* ACU_Term.cc (pairCompare): use ascending rather than descending
	order to sort ACU arg list
	(compareArguments): rewritten to do multiset ordering under the
	assumption that args are sorted in ascending order (Term* version)
	(compareArguments): rewritten to do multiset ordering under the
	assumption that args are sorted in ascending order (DagNode* version)

Fri Jun 27 15:50:27 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_DagNode.hh (class ACU_DagNode): copyEagerUptoReduced2() and
	clearCopyPointers2() made private

	* ACU_DagNode.cc (eliminateArgument): use copyReducible()
	rather than copyUptoEager(); we weren't calling
	clearCopyPointers() which was a serious but subtle bug.
	(copyWithReplacement): use copyReducible()
	rather than copyUptoEager(); we weren't calling
	clearCopyPointers()
	(partialReplace): use copyReducible()
	rather than copyUptoEager(); we weren't calling
	clearCopyPointers()
	(partialConstruct): use copyReducible()
	rather than copyUptoEager(); we weren't calling
	clearCopyPointers()

	* ACU_Symbol.cc (copyAndReduceSubterms): use copyReducible()
	rather than copyUptoEager() and clearCopyPointers();

Wed Jun 25 15:15:12 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_Symbol.cc: added #include "variable.hh"

Tue Jun 24 15:53:31 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_LhsAutomaton.cc (addTopVariable): changed Variable*
	to VariableTerm*

	* ACU_LhsAutomaton.hh (class ACU_LhsAutomaton): changed Variable*
	to VariableTerm* in addTopVariable() decl

	* ACU_Term.cc: added #include "variable.hh"

	* ACU_LhsCompiler1.cc (analyseConstraintPropagation): use VariableTerm::downCast()
	(compileLhs): use VariableTerm::downCast()

	* ACU_Term.cc (compileRhs): use VariableTerm::downCast()

Thu Jun 19 10:38:03 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_Symbol.cc: deleted #include "unionFind.hh"

Tue Jun 17 16:40:13 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_Symbol.cc (compileOpDeclarations): no longer do the assoc
	stuff here

	* ACU_Symbol.hh (class ACU_Symbol): deleted compileEquations() decl

	* ACU_Symbol.cc (finalizeSortInfo): added
	(compileEquations): deleted

	* ACU_Symbol.hh (class ACU_Symbol): added decl for finalizeSortInfo()

Wed Jun 11 10:35:22 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_LhsCompiler1.cc (analyseConstraintPropagation): use
	willGroundOutMatch()
	(compileLhs): use willGroundOutMatch()

	* ACU_LhsCompiler2.cc (findConstraintPropagationSequence): use
	willGroundOutMatch()

Tue Jun 10 10:24:35 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_LhsCompiler2.cc (findConstraintPropagationSequence): don't
	add in grounded out aliens unless they also "honor ground out match".

Fri Jun  6 18:32:04 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_Term.hh (class ACU_Term): deleted addSubsumedAliens() decl

	* ACU_LhsCompiler2.cc (compileAliensOnlyCase): removed call to
	addSubsumedAliens(); We cannot safely add subsumed aliens for the
	following reason: Even though the subsumed alien will not steal
	the only match for its subsuming alien (unless there is no overall
	match) it could take the wrong match if there is a subproblem; and
	we would not discover this until the solve phase when it is too
	late. We could make the use of this optimization conditional on
	there being no subproblem at match time but this complicates what is
	a very minor infrequently usable optimization beyond its utility -
	so we ditch it altogether.
	(addSubsumedAliens): deleted

	* ACU_DagNode.hh (class ACU_DagNode): added
	matchVariableWithExtension() decl

	* ACU_Symbol.hh (class ACU_Symbol): deleted
	matchVariableWithExtension() decl

	* ACU_DagNode.cc (matchVariableWithExtension): added

	* ACU_Symbol.cc (matchVariableWithExtension): deleted

Thu Jun  5 11:48:46 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_DagNode.cc (copyEagerUptoReduced2): adapted from old
	copyEagerUptoReduced()
	(clearCopyPointers2): adapted from old clearCopyPointers()

	* ACU_DagNode.hh (class ACU_DagNode): decls for
	clearCopyPointers() and copyEagerUptoReduced() changed

	* ACU_Subproblem.cc (solveVariables): don't pass context in call
	to computeAssignment()

	* ACU_Subproblem.hh (class ACU_Subproblem): updated
	computeAssignment() decl

	* ACU_Subproblem.cc (computeAssignment): no longer compute sort of
	returned DagNode
	(solveVariables): use inErrorSort() rather than
	computeTrueSortWhilePreservingContext()
	(solveVariables): use checkSort() now that assignment is no longer
	guarenteed to have a sort
	(computeAssignment): removed context arg as no longer needed

	* ACU_Symbol.cc (ACU_Symbol): don't pass stable arg to Symbol; in
	fact we were aleays passing true which was a bug!
	
==============================Engine24====================================

Tue Jun  3 17:01:31 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_CollapseMatcher.cc (uniqueCollapseMatch): now cope with
	abstraction variables
	(multiwayCollapseMatch): removed error check for matching identity
	at top because such a match may ultimately fail due to abstraction
	subproblems and is therefore not necessarily illegal.
	(collapseMatch): handle abstraction variables in multiway collapse
	case

Mon Jun  2 11:16:05 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_Symbol.cc (compileOpDeclarations): move identity code here
	because we need sorts to be done before we can do collapse analysis

	* ACU_LhsAutomaton.cc (dump): handle abstraction variables

	* ACU_Matcher.cc (match): Assert in wrong place

	* ACU_Term.cc (determineCollapseSymbols): fixed bug where we had
	wrong test for setting p.collapseToOurSymbol

	* ACU_LhsAutomaton.cc (addAbstractionVariable): fixed bug where we
	were assigning tv.upperBound to itself rather than initializing it
	from upperBound arg

	* ACU_Matcher.cc (fullMatch): pass nrVariables arg to
	VariableAbstractionSubproblem()

Fri May 30 11:56:07 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_LhsCompiler1.cc (compileLhs): check abstractionVariableIndex
	against NONE rather than 0

	* ACU_Matcher.cc (match): handle the variable only case
	case where the last unbound variable is an abstraction variable
	and there is nothing to bind it to except identity
	(forcedLoneVariableCase): rewritten to deal with abstraction variables
	(fullMatch): deal with abstraction variables

	* ACU_LhsCompiler1.cc (compileLhs): rewritten to
	handle abstractionVariable and honorsGroundOutMatch()

	* ACU_LhsAutomaton.cc (addTopVariable): set abstracted to 0

	* ACU_LhsCompiler1.cc (analyseConstraintPropagation): rewritten to
	handle abstractionVariable and honorsGroundOutMatch()

	* ACU_LhsAutomaton.cc (addAbstractionVariable): added

	* ACU_LhsAutomaton.hh (class ACU_LhsAutomaton): added abstracted
	field to struct TopVariable
	(class ACU_LhsAutomaton): added decl for addAbstractionVariable()

Thu May 29 16:57:27 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_Term.cc (determineCollapseSymbols): major rewrite to set
	honorsGroundOutMatch and collapseToOurSymbol and matchOurIdentity flags
	(dumpArguments): print collapseToOurSymbol and matchOurIdentity

	* ACU_Term.hh (class ACU_Term): added collapseToOurSymbol and
	matchOurIdentity to struct Pair

Wed May 28 11:29:39 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_Subproblem.cc (deepSelfDestruct): fixed long standing memory
	leak where we were deleting rather than deepSelfDestruct()ing edge
	subproblems

	* ACU_CollapseMatcher.cc (multiwayCollapseMatch): pass identityDag
	arg to bindUnboundVariablesToIdentity()
	(bindUnboundVariablesToIdentity): added identityDag arg

	* ACU_LhsAutomaton.hh (class ACU_LhsAutomaton): added identityDag
	arg to bindUnboundVariablesToIdentity()

	* ACU_LhsAutomaton.cc: added include for SubproblemDisjunction

	* ACU_CollapseMatcher.cc (multiwayCollapseMatch): now use
	SubproblemDisjunction rather than ACU_CollapseSubproblem

Tue May 27 11:19:03 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_CollapseMatcher.cc (multiwayCollapseMatch): considerably
	simplified using DagNode::matchVariable()

Fri May 23 14:18:00 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_CollapseSubproblem.cc: created

	* ACU_CollapseMatcher.cc (multiwayCollapseMatch): general case added

	* ACU_CollapseSubproblem.hh (class ACU_CollapseSubproblem): created

	* ACU_CollapseMatcher.cc (uniqueCollapseMatch): code cleaning;
	vi eliminated
	(bindUnboundVariablesToIdentity): added
	(multiwayCollapseMatch): implemented 1 bound variable, identity
	subject, 0 viable variables and 1 viable variable cases 

Thu May 22 10:48:52 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_Matcher.cc (match): Don't do matchAtTop assertion until
	we've established that the subject actualy has our symbol on top
	since an alien (e.g. free) symbol may not have extension.

	* ACU_LhsCompiler1.cc (compileLhs): fixed bug where
	we were using !empty rather than !empty() to decide whether
	collapse possible
	(compileLhs): uniqueCollapseAutomaton must be passed our
	matchAtTop flag to ensure matching with extension is performed if
	necessary.

	* ACU_CollapseMatcher.cc (multiwayCollapseMatch): added
	(uniqueCollapseMatch): added

Wed May 21 15:19:01 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_LhsAutomaton.cc (ACU_LhsAutomaton): initialize
	uniqueCollapseAutomaton

	* ACU_LhsAutomaton.hh (class ACU_LhsAutomaton): add
	uniqueCollapseAutomaton arg to ctor decl

	* ACU_LhsCompiler1.cc (compileLhs): pass flag saying whether we
	could collapse to ACU_LhsAutomaton()
	(compileLhs): compute uniqueCollapseAutomaton if needed

	* ACU_LhsAutomaton.hh (class ACU_LhsAutomaton): add
	collapsePosible arg to ctor decl

	* ACU_LhsAutomaton.cc (ACU_LhsAutomaton): initialize collapse
	possible flag

	* ACU_Term.cc (determineCollapseSymbols): need to insert
	abstraction variables for subterms that can't collapse but which
	have our identity as their top symbol and are non-ground.
	(determineCollapseSymbols): non longer assume that a subterm might
	match the idenitity element because it has the same top symbol as
	the identity element - check to see also that it is non-ground.

Tue May 20 16:24:31 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_Term.cc (dumpArguments): added

	* ACU_Term.hh (class ACU_Term): added decl for dumpArguments()

	* ACU_Matcher.cc (match): temporarily comment out unfinished
	collapse code so we can test variable abstraction

	* ACU_Term.cc (determineCollapseSymbols): rewritten to do
	selective variable abstraction

Mon May 19 10:48:23 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_Term.cc (determineCollapseSymbols): now fill out
	uniqueCollapseSubtermIndex and abstractionVariableIndex

	* ACU_Term.hh (class ACU_Term): added uniqueCollapseSubtermIndex
	(class ACU_Term): added abstractionVariableIndex to Pair (no
	longer really a pair! If this works out we will rename it to Triple.

Fri May 16 11:38:36 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_CollapseMatcher.cc: created

	* ACU_Matcher.cc (match): added call to collapseMatch() in the
	case where top symbol mis-matches and collapsePossible

	* ACU_LhsAutomaton.hh (class ACU_LhsAutomaton): added
	collapsePossible flag and uniqueCollapseAutomaton pointer

	* ACU_Term.cc (compileRhs): pass Term* rather than Symbol* for
	first arg of addArgument()

	* ACU_RhsAutomaton.hh (class ACU_RhsAutomaton): change decl for
	addArgument()

	* ACU_RhsAutomaton.cc (addArgument): rewritten to use se
	Term::stable() rather than Symbol::stable(). First arg is now a Term*

	* ACU_LhsAutomaton.cc (addGroundedOutAlien): use Term::stable()
	rather than Symbol::stable()
	(addNonGroundAlien): use Term::stable() rather than Symbol::stable()

Wed May 14 15:42:04 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_Term.cc (analyseCollapses): deleted

	* ACU_Term.hh (class ACU_Term): deleted analyseCollapses() decl

	* ACU_Term.cc (determineCollapseSymbols): added

	* ACU_Term.hh (class ACU_Term): added decl for determineCollapseSymbols()

	* ACU_Symbol.cc (eqRewrite): changed comment on repudiate call now
	that inErrorSort() can leave sort info behind

Tue May 13 10:29:27 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_LhsAutomaton.cc: comment out #include "sortCheckSubproblem.hh"

	* ACU_Matcher.cc (forcedLoneVariableCase): use
	DagNode::checkSort() to simplify code

Fri May  9 15:55:04 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_Term.cc (analyseCollapses): fixed bug where we need to check
	multiplicity against 1 in order to return early

Wed May  7 16:46:17 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_Term.cc (analyseCollapses): added

Thu Apr 10 16:16:03 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_Matcher.cc (forcedLoneVariableCase): must repudiateSort() in
	the case where the base sort is not small enough and
 	the top symbol is not sort constraint free as the
	base sort we calculated may not be the true sort and will inhibit
	the calculation of the true sort during the solution of the sort
	check subprblem.

Wed Apr  2 16:54:05 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_Subproblem.cc (solveVariables): when solving a trivial
	system with extension, use extensionInfo->setWholeFlag(true)
	rather than extensionInfo->clear() (trying to fix UMR:
	Uninitialized memory read reported by purify).

Fri Mar 28 16:51:53 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_DagNode.hh (class ACU_DagNode): decl for makeExtensionInfo()
	added

	* ACU_DagNode.cc (makeExtensionInfo): added

Wed Mar 26 11:02:46 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_Matcher.cc (buildBipartiteGraph): rewritten to use findFirstOccurrence()
	(aliensOnlyMatch): rewritten to use findFirstOccurrence()
	(eliminateGroundedOutAliens): rewritten to use findFirstOccurrence()

	* ACU_GreedyMatcher.cc (greedyMatch): test top symbol before multiplicity

Tue Mar 25 12:17:05 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_GreedyMatcher.cc (greedyMatch): rewritten to use findFirstOccurrence()

	* ACU_DagNode.hh (class ACU_DagNode): added decl for
	findFirstOccurrence()

	* ACU_DagNode.cc (findFirstOccurrence): added

	* ACU_Subproblem.cc (computeAssignment): initialized col to avoid
	spurious uninit warning from g++

	* ACU_LhsCompiler3.cc (compileGreedyAndFullCases): pass term in
	addNonGroundAlien() call

	* ACU_LhsCompiler2.cc (compileAliensOnlyCase): pass term in
	addNonGroundAlien() calls

	* ACU_LhsCompiler1.cc (compileLhs): pass term in
	addGroundedOutAlien() call

	* ACU_LhsAutomaton.cc (addGroundedOutAlien): store topSymbol if
	stable, 0 otherwise
	(addNonGroundAlien): store topSymbol if stable, 0 otherwise

	* ACU_LhsAutomaton.hh (class ACU_LhsAutomaton): added topSymbol field
	to NonGroundAlien struct; added Term* alien arg to
	addGroundedOutAlien() and addNonGroundAlien()

	* ACU_GreedyMatcher.cc (greedyPureMatch): new condition for
	choosing between false and UNDECIDED when we can't find a variable
	to assign some subject to in phase 2.

Fri Mar 21 18:54:28 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_GreedyMatcher.cc (greedyPureMatch): new technique for
	calculating failure mode in phase 1.
	(greedyMatch): call greedyPureMatch with extra arg

	* ACU_Matcher.cc (match): call greedyPureMatch with extra arg

Thu Mar 20 16:05:15 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_Matcher.cc (multiplicityChecks): split off case where
	maxPatternMultiplicity = 1 

	* ACU_LhsAutomaton.hh (class ACU_LhsAutomaton): extensionInfo
	removed from multiplicityChecks and totalMultiplicity added as
	data member; the aim is to save the totalSubjectMultiplicity so we
	don't have to mess with extensionInfo until it is clear that it is
	needed. (After checking with quantify)

Tue Mar 18 16:07:47 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_Symbol.cc (matchVariableWithExtension): set extensionInfo
	upperBound to avoid crashing when trying to build diophantine system

Wed Feb 19 16:08:49 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_LhsCompiler3.cc (findFullSequence): remember to expand
	sequenece before putting stuff in it.

Thu Feb 13 10:41:49 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_LhsCompiler1.cc (compileLhs): greedy = !inErrorSort

Wed Feb 12 16:11:35 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_GreedyMatcher.cc (greedyPureMatch): make sure we don't
	assign to much to extension

	* ACU_Subproblem.cc (extractDiophantineSystem): use extensionInfo
	upper bound to bound extension row in diophantine system

	* ACU_LhsAutomaton.hh (class ACU_LhsAutomaton): amended
	multiplicityChecks() decl

	* ACU_ExtensionInfo.hh (setUpperBound): added
	(getUpperBound): added

	* ACU_Matcher.cc (match): pass extensionInfo to
	multiplicityChecks(); test extensionInfo rather than matchAtTop
	(multiplicityChecks): set upper bound on size of extension if necessary

	* ACU_Subproblem.hh (class ACU_Subproblem): identityDag deleted

	* ACU_Subproblem.cc (solveVariables): added code to bind variables
	to idenity in the case where ther are unbound variables and no system
	(solveVariables): handle the case where the sort of the dag node
	reeturn by computeAssignment() is unknown; this can only be the
	identity case
	(solveVariables): unbinding code simplified
	(extractDiophantineSystem): handle case where there are no
	unused subjects but all variables case take the identity by
	keeping track of nrNonIdentityVariables
	(computeAssignment): don't bother computing the sort of the
	identity dag since our lower bound condition guarentees that the
	variable can take the identity element
	(computeAssignment): return 0 in identity case
	(solveVariables): handle case where 0 is returned from computeAssignment()

Fri Feb  7 14:49:35 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_Term.cc (findEagerVariables): static_cast removed for symbol()
	(markEagerArguments): static_cast removed for symbol()

	* ACU_DagNode.cc (copyEagerUptoReduced): static_cast removed for symbol()
	(overwriteWithClone): static_cast removed for symbol()
	(makeClone): static_cast removed for symbol()
	(copyWithReplacement): static_cast removed for symbol()
	(partialReplace): static_cast removed for symbol()
	(partialConstruct): static_cast removed for symbol()
	(eliminateArgument): static_cast removed for symbol()

	* ACU_DagNode.hh (symbol): added

	* ACU_Subproblem.hh (class ACU_Subproblem): identityDag pointer added

	* ACU_Subproblem.cc (addEdge): optimized
	(addTopVariable): optimized
	(extractDiophantineSystem): optimized
	(solveVariables): zero out idenity dag pointer since the identity
	element that it may point to may get garbage collected before in
	can be used
	(computeAssignment): handle identity case

	* ACU_Matcher.cc (fullMatch): pass 0 as lower bound for variables
	that can take identity

	* ACU_LhsCompiler1.cc (compileLhs): set error sort flag only if we
	are matching with extension. Prevent compiling with greedy
	strategy if we are in the error sort flag is set.
 	This fixes a bug because the ACU
	greedy matcher does not do sort check for matched part.

Thu Feb  6 16:46:16 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_GreedyMatcher.cc (greedyMatch): simplified
	(greedyPureMatch): deal with identity in first phase by allowing a
	variable with takeIdentity set to have no firstSubject if none can
	be found.
	(greedyPureMatch): in 3rd phase deal with variables that were
	assigned nothing by binding them to identity dag

Wed Feb  5 11:57:26 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_Symbol.cc (ACU_Symbol): zero identityAutomaton and
	identitySubstitution. Handle no identity case.

	* ACU_Symbol.hh (makeIdentityDag): added

	* ACU_Symbol.cc (compileEquations): added code to compile a
	rhsAutomaton for our identity element. Handle no identity case 

	* ACU_GreedyMatcher.cc: created

	* ACU_Matcher.cc (multiplicityChecks): totalPatternMultiplicity ->
	totalLowerBound
	(eliminateBoundVariables): handle the case where a top variable is
	bound to our identity
	(match): recognize and handle special case of one variable which
	can take identity vs no subjects (no extension case)

Tue Feb  4 12:18:37 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_LhsAutomaton.cc (updateTotals): totalPatternMultiplicity ->
	totalLowerBound
	(addTopVariable): fill out takeIdentity field and take it into
	account when updating totals
	(dump): output takeIdenity field

	* ACU_LhsAutomaton.hh (class ACU_LhsAutomaton): takeIdentity field
	added to struct TopVariable
	(class ACU_LhsAutomaton): totalPatternMultiplicity ->
	totalLowerBound (since identity may result in some pattern
	variables not being counted)

	* ACU_LhsCompiler3.cc (findFullSequence): use weakConstraintPropogation()

	* ACU_LhsCompiler2.cc (compileAliensOnlyCase): use weakConstraintPropogation()

	* ACU_LhsCompiler1.cc (weakConstraintPropogation): added

	* ACU_LhsCompiler3.cc (compileGreedyAndFullCases): simplified
	using findFullSequence()
	(findFullSequence): added

Fri Jan 31 17:07:29 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_LhsCompiler3.cc (compileGreedyAndFullCases): removed greedy
	argument; code cleaning
	(lengthCompare): deleted
	(findGreedySequence): no longer deal with fully independent aliens
	first as I can't see any justification for doing so
	(findIndependentSets): no longer sort independent sets by length
	(can't think of any justification).

	* ACU_LhsCompiler1.cc (compileLhs): compileGreedyAndFullCases() no
	longer takes greedy argument

	* ACU_LhsCompiler2.cc (compileAliensOnlyCase): code cleaning

	* ACU_LhsCompiler1.cc (compileLhs): code cleaning; make sure
	subproblemLikely is false in lone variable case

Thu Jan 30 16:17:56 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_LhsCompiler3.cc: created
	(compileGreedyAndFullCases): added

	* ACU_Term.hh (symbol): added

	* ACU_LhsCompiler2.cc: created
	(compileAliensOnlyCase): added

Mon Jan 27 10:59:41 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_LhsAutomaton.hh: created

	* ACU_LhsAutomaton.cc: created

	* ACU_Matcher.cc: created

Thu Jan 16 18:17:11 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_RhsAutomaton.hh (class ACU_RhsAutomaton): topSymbol is
	ACU_Symbol* rather that Symbol*

	* ACU_RhsAutomaton.cc (construct): added call to eliminate identity
	elements
	(replace): added call to eliminate identity elements
	(ACU_RhsAutomaton): take ACU_Symbol* rather that Symbol*

Mon Jan 13 12:53:38 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_RhsAutomaton.hh: created

Fri Jan 10 11:15:42 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_Term.cc: created
	(normalize): now delete idenity elements, collapsing to subterm
	where necessary

	* ACU_DagNode.hh (class ACU_DagNode): enum NormalizationResult
	removed; declaration for eliminateArgument() added

	* ACU_DagNode.cc (copyWithReplacement): handle case where collapse
	is avoided because single remaining argument has multiplicity > 1
	(partialReplace): handle case where collapse
	is avoided because single remaining argument has multiplicity > 1
	(partialConstruct): handle case where collapse
	is avoided because single remaining argument has multiplicity > 1
	(eliminateArgument): added to handle the removal of identity elements

Thu Jan  9 15:40:11 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_DagNode.cc: created
	(overwriteWithClone): fixed serious bug where we were copying sort
	of overwritten node rather than overwriting node
	(mergeSortAndUniquize): old commented out flip code removed
	(eliminateSubject): unnecessary ACU_DagNode::'s removed
	(partialConstruct): handle case where replacement it the identity element
	(partialReplace): handle case where replacement it the identity element
	(copyWithReplacement): handle case where replacement it the identity element

Wed Jan  8 10:26:06 1997  Steven Eker  <eker@lilac.csl.sri.com>

	* ACU_Symbol.cc (eqRewrite): now cope with the possibility that
	whenever we normalize at top it is possible that we could collpase
	out of the current theory
	(computeBaseSort): added uniform sort code optimization;
	simplified uniform sort code computation by passing vectors of
	sort codes rather thhan vectors of vectors of int

	* ACU_DagNode.hh (class ACU_DagNode): added enum NormalizationResult

	* ACU_Symbol.cc: created
	(~ACU_Symbol): added
	(compileEquations): added as a hack to process identity element
	after all other op decl processing has been done.
	(ACU_Symbol): do normalization here to avoid problem of later
	identities that could possibly depend on this one.

	* ACU_DagArgumentIterator.cc: created

	* ACU_ArgumentIterator.hh (class ACU_ArgumentIterator): created

	* ACU_DagArgumentIterator.hh (class ACU_DagArgumentIterator): created

	* ACU_ArgumentIterator.cc: created

	* ACU_ExtensionInfo.hh (class ACU_ExtensionInfo): created

	* ACU_Theory.cc: created

	* ACU_Theory.hh: created

	* ACU_Term.hh (class ACU_Term): created

	* ACU_Symbol.hh (getIdentity): added

	* ACU_DagNode.hh (class ACU_DagNode): created

	* ACU_Symbol.hh (class ACU_Symbol): created

