//
// Subroutine of explain
// A step of explanation for x and y
//
void Egraph::expExplainAlongPath ( Enode * x, Enode * y )
{
Enode * v = expHighestNode( x );
Enode * to = expHighestNode( y );
while ( v != to )
{
Enode * p = v->getExpParent( );
assert( p != NULL );
Enode * r = v->getExpReason( );
// If it is not a congruence edge
if ( r != NULL )
{
if ( !isDup1( r ) )
{
assert( r->isTerm( ) );
explanation.push_back( r );
storeDup1( r );
}
}
// Otherwise it is a congruence edge
// This means that the edge is linking nodes
// like (v)f(a1,...,an) (p)f(b1,...,bn), and that
// a1,...,an = b1,...bn. For each pair ai,bi
// we have therefore to compute the reasons
else
{
assert( v->getCar( ) == p->getCar( ) );
assert( v->getArity( ) == p->getArity( ) );
expEnqueueArguments( v, p );
}
#ifdef PRODUCE_PROOF
if ( config.produce_inter > 0
&& config.logic != QF_AX )
{
cgraph.addCNode( v );
cgraph.addCNode( p );
cgraph.addCEdge( v, p, r );
}
#endif
expUnion( v, p );
v = expHighestNode( p );
}
}
//
// 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( );
}
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( );
}
bool Egraph::isPureUF( Enode * e )
{
assert( config.sat_lazy_dtc != 0 );
assert( config.logic == QF_UFIDL
|| config.logic == QF_UFLRA );
assert( e );
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->isArithmeticOp( ) )
{
doneDup1( );
return false;
}
assert( !isDup1( enode ) );
storeDup1( enode );
}
doneDup1( );
return true;
}
void Egraph::getInterfaceVars( Enode * e, set< Enode * > & iv )
{
assert( config.produce_inter != 0 );
assert( config.sat_lazy_dtc != 0 );
assert( config.logic == QF_UFIDL
|| config.logic == QF_UFLRA );
assert( e );
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( );
if ( enode->isVar( )
&& interface_terms_cache.find( enode ) != interface_terms_cache.end( ) )
iv.insert( enode );
assert( !isDup1( enode ) );
storeDup1( enode );
}
doneDup1( );
}