//
// Ackermann related routines
//
void
Egraph::retrieveFunctionApplications( Enode * formula )
{
assert( formula );
vector< Enode * > unprocessed_enodes;
initDup1( );
unprocessed_enodes.push_back( formula );
//
// Visit the DAG of the formula from the leaves to the root
//
while( !unprocessed_enodes.empty( ) )
{
Enode * enode = unprocessed_enodes.back( );
//
// Skip if the node has already been processed before
//
if ( isDup1( enode ) )
{
unprocessed_enodes.pop_back( );
continue;
}
bool unprocessed_children = false;
Enode * arg_list;
for ( arg_list = enode->getCdr( ) ;
arg_list != enil ;
arg_list = arg_list->getCdr( ) )
{
Enode * arg = arg_list->getCar( );
assert( arg->isTerm( ) );
//
// Push only if it is unprocessed
//
if ( !isDup1( arg ) )
{
unprocessed_enodes.push_back( arg );
unprocessed_children = true;
}
}
//
// SKip if unprocessed_children
//
if ( unprocessed_children )
continue;
unprocessed_enodes.pop_back( );
//
// At this point, every child has been processed
//
if ( enode->isUf( ) || enode->isUp( ) )
{
if ( uf_to_appl_cache[ enode->getCar( ) ].insert( enode ).second )
{
uf_to_appl[ enode->getCar( ) ].push_back( enode );
undo_stack_oper.push_back( ACK_APPL );
undo_stack_term.push_back( enode );
}
}
assert( !isDup1( enode ) );
storeDup1( enode );
}
doneDup1( );
}
Enode * Egraph::canonizeDTC( Enode * formula, bool split_eqs )
{
assert( config.sat_lazy_dtc != 0 );
assert( config.logic == QF_UFLRA
|| config.logic == QF_UFIDL );
list< Enode * > dtc_axioms;
vector< Enode * > unprocessed_enodes;
initDupMap1( );
unprocessed_enodes.push_back( formula );
//
// Visit the DAG of the formula from the leaves to the root
//
while( !unprocessed_enodes.empty( ) )
{
Enode * enode = unprocessed_enodes.back( );
//
// Skip if the node has already been processed before
//
if ( valDupMap1( enode ) != NULL )
{
unprocessed_enodes.pop_back( );
continue;
}
bool unprocessed_children = false;
Enode * arg_list;
for ( arg_list = enode->getCdr( )
; arg_list != enil
; arg_list = arg_list->getCdr( ) )
{
Enode * arg = arg_list->getCar( );
assert( arg->isTerm( ) );
//
// Push only if it is unprocessed
//
if ( valDupMap1( arg ) == NULL )
{
unprocessed_enodes.push_back( arg );
unprocessed_children = true;
}
}
//
// SKip if unprocessed_children
//
if ( unprocessed_children )
continue;
unprocessed_enodes.pop_back( );
Enode * result = NULL;
//
// Replace arithmetic atoms with canonized version
//
if ( enode->isTAtom( )
&& !enode->isUp( ) )
{
// No need to do anything if node is purely UF
if ( isRootUF( enode ) )
{
if ( config.verbosity > 2 )
cerr << "# Egraph::Skipping canonization of " << enode << " as it's root is purely UF" << endl;
result = enode;
}
else
{
LAExpression a( enode );
result = a.toEnode( *this );
#ifdef PRODUCE_PROOF
const uint64_t partitions = getIPartitions( enode );
assert( partitions != 0 );
setIPartitions( result, partitions );
#endif
if ( split_eqs && result->isEq( ) )
{
#ifdef PRODUCE_PROOF
if ( config.produce_inter > 0 )
opensmt_error2( "can't compute interpolant for equalities at the moment ", enode );
#endif
LAExpression aa( enode );
Enode * e = aa.toEnode( *this );
#ifdef PRODUCE_PROOF
assert( partitions != 0 );
setIPartitions( e, partitions );
#endif
Enode * lhs = e->get1st( );
Enode * rhs = e->get2nd( );
Enode * leq = mkLeq( cons( lhs, cons( rhs ) ) );
LAExpression b( leq );
leq = b.toEnode( *this );
#ifdef PRODUCE_PROOF
assert( partitions != 0 );
setIPartitions( leq, partitions );
#endif
Enode * geq = mkGeq( cons( lhs, cons( rhs ) ) );
LAExpression c( geq );
geq = c.toEnode( *this );
#ifdef PRODUCE_PROOF
assert( partitions != 0 );
setIPartitions( geq, partitions );
#endif
Enode * not_e = mkNot( cons( enode ) );
Enode * not_l = mkNot( cons( leq ) );
Enode * not_g = mkNot( cons( geq ) );
// Add clause ( !x=y v x<=y )
Enode * c1 = mkOr( cons( not_e
, cons( leq ) ) );
// Add clause ( !x=y v x>=y )
Enode * c2 = mkOr( cons( not_e
, cons( geq ) ) );
// Add clause ( x=y v !x>=y v !x<=y )
Enode * c3 = mkOr( cons( enode
, cons( not_l
, cons( not_g ) ) ) );
// Add conjunction of clauses
Enode * ax = mkAnd( cons( c1
, cons( c2
, cons( c3 ) ) ) );
dtc_axioms.push_back( ax );
result = enode;
}
}
}
//
// If nothing have been done copy and simplify
//
if ( result == NULL )
result = copyEnodeEtypeTermWithCache( enode );
assert( valDupMap1( enode ) == NULL );
storeDupMap1( enode, result );
#ifdef PRODUCE_PROOF
if ( config.produce_inter > 0 )
{
// Setting partitions for result
setIPartitions( result, getIPartitions( enode ) );
// Setting partitions for negation as well occ if atom
if ( result->hasSortBool( ) )
{
setIPartitions( mkNot( cons( result ) )
, getIPartitions( enode ) );
}
}
#endif
}
Enode * new_formula = valDupMap1( formula );
assert( new_formula );
doneDupMap1( );
if ( !dtc_axioms.empty( ) )
{
dtc_axioms.push_back( new_formula );
new_formula = mkAnd( cons( dtc_axioms ) );
}
return new_formula;
}
void Egraph::gatherInterfaceTerms( Enode * e )
{
assert( config.sat_lazy_dtc != 0 );
assert( config.logic == QF_UFIDL
|| config.logic == QF_UFLRA );
assert( e );
if ( config.verbosity > 2 )
cerr << "# Egraph::Gathering interface terms" << endl;
vector< Enode * > unprocessed_enodes;
initDup1( );
unprocessed_enodes.push_back( e );
//
// Visit the DAG of the term from the leaves to the root
//
while( !unprocessed_enodes.empty( ) )
{
Enode * enode = unprocessed_enodes.back( );
//
// Skip if the node has already been processed before
//
if ( isDup1( enode ) )
{
unprocessed_enodes.pop_back( );
continue;
}
bool unprocessed_children = false;
Enode * arg_list;
for ( arg_list = enode->getCdr( ) ;
arg_list != enil ;
arg_list = arg_list->getCdr( ) )
{
Enode * arg = arg_list->getCar( );
assert( arg->isTerm( ) );
//
// Push only if it is unprocessed
//
if ( !isDup1( arg ) )
{
unprocessed_enodes.push_back( arg );
unprocessed_children = true;
}
}
//
// SKip if unprocessed_children
//
if ( unprocessed_children )
continue;
unprocessed_enodes.pop_back( );
//
// At this point, every child has been processed
//
if ( enode->isUFOp( ) )
{
// Retrieve arguments
for ( Enode * arg_list = enode->getCdr( )
; !arg_list->isEnil( )
; arg_list = arg_list->getCdr( ) )
{
Enode * arg = arg_list->getCar( );
// This is for sure an interface term
if ( ( arg->isArithmeticOp( )
|| arg->isConstant( ) )
&& interface_terms_cache.insert( arg ).second )
{
if ( config.verbosity > 2 )
cerr << "# Egraph::Added interface term: " << arg << endl;
// Save info for backtracking
undo_stack_oper.push_back( INTERFACE_TERM );
undo_stack_term.push_back( arg );
}
// We add this variable to the potential
// interface terms or to interface terms if
// already seen in LA
else if ( arg->isVar( ) || arg->isConstant( ) )
{
if ( it_la.find( arg ) == it_la.end( ) )
{
if ( it_uf.insert( arg ).second )
{
// Insertion took place, save undo info
undo_stack_oper.push_back( INTERFACE_UF );
undo_stack_term.push_back( arg );
}
}
else if ( interface_terms_cache.insert( arg ).second )
{
interface_terms.push_back( arg );
if ( config.verbosity > 2 )
cerr << "# Egraph::Added interface term: " << arg << endl;
// Save info for backtracking
undo_stack_oper.push_back( INTERFACE_TERM );
undo_stack_term.push_back( arg );
}
}
}
}
if ( enode->isArithmeticOp( )
&& !isRootUF( enode ) )
{
// Retrieve arguments
for ( Enode * arg_list = enode->getCdr( )
; !arg_list->isEnil( )
; arg_list = arg_list->getCdr( ) )
{
Enode * arg = arg_list->getCar( );
// This is for sure an interface term
if ( arg->isUFOp( )
&& !arg->isUp( )
&& interface_terms_cache.insert( arg ).second )
{
interface_terms.push_back( arg );
if ( config.verbosity > 2 )
cerr << "# Egraph::Added interface term: " << arg << endl;
// Save info for backtracking
undo_stack_oper.push_back( INTERFACE_TERM );
undo_stack_term.push_back( arg );
}
// We add this variable to the potential
// interface terms or to interface terms if
// already seen in UF
else if ( arg->isVar( ) || arg->isConstant( ) )
{
if ( it_uf.find( arg ) == it_uf.end( ) )
{
if ( it_la.insert( arg ).second )
{
// Insertion took place, save undo info
undo_stack_oper.push_back( INTERFACE_LA );
undo_stack_term.push_back( arg );
}
}
else if ( interface_terms_cache.insert( arg ).second )
{
interface_terms.push_back( arg );
if ( config.verbosity > 2 )
cerr << "# Egraph::Added interface term: " << arg << endl;
// Save info for backtracking
undo_stack_oper.push_back( INTERFACE_TERM );
undo_stack_term.push_back( arg );
}
}
}
}
assert( !isDup1( enode ) );
storeDup1( enode );
}
doneDup1( );
}