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/********************* */
/*! \file theory_builtin.cpp
** \verbatim
** Original author: mdeters
** Major contributors: none
** Minor contributors (to current version): none
** This file is part of the CVC4 prototype.
** Copyright (c) 2009, 2010 The Analysis of Computer Systems Group (ACSys)
** Courant Institute of Mathematical Sciences
** New York University
** See the file COPYING in the top-level source directory for licensing
** information.\endverbatim
**
** \brief Implementation of the builtin theory.
**
** Implementation of the builtin theory.
**/
#include "theory/builtin/theory_builtin.h"
#include "theory/valuation.h"
#include "expr/kind.h"
using namespace std;
namespace CVC4 {
namespace theory {
namespace builtin {
Node TheoryBuiltin::simplify(TNode in, Substitutions& outSubstitutions) {
if(in.getKind() == kind::EQUAL) {
Node lhs = d_valuation.simplify(in[0], outSubstitutions);
Node rhs = d_valuation.simplify(in[1], outSubstitutions);
Node n = lhs.eqNode(rhs);
if( n[0].getMetaKind() == kind::metakind::VARIABLE &&
n[1].getMetaKind() == kind::metakind::CONSTANT ) {
Debug("simplify:builtin") << "found new substitution! "
<< n[0] << " => " << n[1] << endl;
outSubstitutions.push_back(make_pair(n[0], n[1]));
// with our substitutions we've subsumed the equality
return NodeManager::currentNM()->mkConst(true);
} else if( n[1].getMetaKind() == kind::metakind::VARIABLE &&
n[0].getMetaKind() == kind::metakind::CONSTANT ) {
Debug("simplify:builtin") << "found new substitution! "
<< n[1] << " => " << n[0] << endl;
outSubstitutions.push_back(make_pair(n[1], n[0]));
// with our substitutions we've subsumed the equality
return NodeManager::currentNM()->mkConst(true);
}
} else if(in.getKind() == kind::NOT && in[0].getKind() == kind::DISTINCT) {
TNode::iterator found = in[0].end();
for(TNode::iterator i = in[0].begin(), i_end = in[0].end(); i != i_end; ++i) {
if((*i).getMetaKind() == kind::metakind::CONSTANT) {
found = i;
break;
}
}
if(found != in[0].end()) {
for(TNode::iterator i = in[0].begin(), i_end = in[0].end(); i != i_end; ++i) {
if(i != found) {
outSubstitutions.push_back(make_pair(*i, *found));
}
}
// with our substitutions we've subsumed the (NOT (DISTINCT...))
return NodeManager::currentNM()->mkConst(true);
}
}
return in;
}
Node TheoryBuiltin::getValue(TNode n) {
switch(n.getKind()) {
case kind::VARIABLE:
// no variables that the builtin theory is responsible for
Unreachable();
case kind::EQUAL: { // 2 args
// has to be an EQUAL over tuples, since all others should be
// handled elsewhere
Assert(n[0].getKind() == kind::TUPLE &&
n[1].getKind() == kind::TUPLE);
return NodeManager::currentNM()->
mkConst( getValue(n[0]) == getValue(n[1]) );
}
case kind::TUPLE: { // 2+ args
NodeBuilder<> nb(kind::TUPLE);
for(TNode::iterator i = n.begin(),
iend = n.end();
i != iend;
++i) {
nb << d_valuation.getValue(*i);
}
return Node(nb);
}
default:
// all other "builtins" should have been rewritten away or handled
// by the valuation, or handled elsewhere.
Unhandled(n.getKind());
}
}
}/* CVC4::theory::builtin namespace */
}/* CVC4::theory */
}/* CVC4 namespace */
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