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make difference logic simplex optimizer incremental

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Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>
This commit is contained in:
Nikolaj Bjorner 2014-09-07 16:46:46 -07:00
parent c1580fb85a
commit d9c61464d0
6 changed files with 159 additions and 56 deletions
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175
src/smt/theory_diff_logic_def.h
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@ -29,8 +29,6 @@ Revision History:
#include"warning.h"
#include"smt_model_generator.h"
#include"model_implicant.h"
#include"simplex.h"
#include"simplex_def.h"
using namespace smt;
@ -343,7 +341,13 @@ void theory_diff_logic<Ext>::pop_scope_eh(unsigned num_scopes) {
m_asserted_atoms.shrink(s.m_asserted_atoms_lim);
m_asserted_qhead = s.m_asserted_qhead_old;
m_scopes.shrink(new_lvl);
unsigned num_edges = m_graph.get_num_edges();
m_graph.pop(num_scopes);
if (num_edges != m_graph.get_num_edges() && m_num_simplex_edges > 0) {
m_S.reset();
m_num_simplex_edges = 0;
m_objective_rows.reset();
}
theory::pop_scope_eh(num_scopes);
}
@ -1066,12 +1070,120 @@ void theory_diff_logic<Ext>::get_implied_bound_antecedents(edge_id bridge_edge,
m_graph.explain_subsumed_lazy(bridge_edge, subsumed_edge, f);
}
template<typename Ext>
unsigned theory_diff_logic<Ext>::node2simplex(unsigned v) {
//return v;
return m_objectives.size() + 2*v + 1;
}
template<typename Ext>
unsigned theory_diff_logic<Ext>::edge2simplex(unsigned e) {
//return m_graph.get_num_nodes() + e;
return m_objectives.size() + 2*e;
}
template<typename Ext>
unsigned theory_diff_logic<Ext>::obj2simplex(unsigned e) {
//return m_graph.get_num_nodes() + m_graph.get_num_edges() + e;
return e;
}
template<typename Ext>
unsigned theory_diff_logic<Ext>::num_simplex_vars() {
//return m_graph.get_num_nodes() + m_graph.get_num_edges() + m_objectives.size();
return m_objectives.size() + std::max(2*m_graph.get_num_edges(),2*m_graph.get_num_nodes()+1);
}
template<typename Ext>
bool theory_diff_logic<Ext>::is_simplex_edge(unsigned e) {
#if 0
return
m_graph.get_num_nodes() <= e &&
e < m_graph.get_num_nodes() + m_graph.get_num_edges();
#else
if (e < m_objectives.size()) return false;
e -= m_objectives.size();
return (0 == (e & 0x1));
#endif
}
template<typename Ext>
unsigned theory_diff_logic<Ext>::simplex2edge(unsigned e) {
SASSERT(is_simplex_edge(e));
//return e - m_graph.get_num_nodes();
return (e - m_objectives.size())/2;
}
template<typename Ext>
void theory_diff_logic<Ext>::update_simplex(Simplex& S) {
unsigned num_nodes = m_graph.get_num_nodes();
vector<dl_edge<GExt> > const& es = m_graph.get_all_edges();
S.ensure_var(num_simplex_vars());
for (unsigned i = 0; i < num_nodes; ++i) {
numeral const& a = m_graph.get_assignment(i);
rational fin = a.get_rational().to_rational();
rational inf = a.get_infinitesimal().to_rational();
mpq_inf q(fin.to_mpq(), inf.to_mpq());
S.set_value(node2simplex(i), q);
}
S.set_lower(node2simplex(get_zero()), mpq_inf(mpq(0), mpq(0)));
S.set_upper(node2simplex(get_zero()), mpq_inf(mpq(0), mpq(0)));
svector<unsigned> vars;
unsynch_mpq_manager mgr;
scoped_mpq_vector coeffs(mgr);
coeffs.push_back(mpq(1));
coeffs.push_back(mpq(-1));
coeffs.push_back(mpq(-1));
vars.resize(3);
for (unsigned i = m_num_simplex_edges; i < es.size(); ++i) {
// t - s <= w
// =>
// t - s - b = 0, b >= w
dl_edge<GExt> const& e = es[i];
unsigned base_var = edge2simplex(i);
vars[0] = node2simplex(e.get_target());
vars[1] = node2simplex(e.get_source());
vars[2] = base_var;
S.add_row(base_var, 3, vars.c_ptr(), coeffs.c_ptr());
}
m_num_simplex_edges = es.size();
for (unsigned i = 0; i < es.size(); ++i) {
dl_edge<GExt> const& e = es[i];
unsigned base_var = edge2simplex(i);
if (e.is_enabled()) {
numeral const& w = e.get_weight();
rational fin = w.get_rational().to_rational();
rational inf = w.get_infinitesimal().to_rational();
mpq_inf q(fin.to_mpq(),inf.to_mpq());
S.set_upper(base_var, q);
}
else {
S.unset_upper(base_var);
}
}
for (unsigned v = m_objective_rows.size(); v < m_objectives.size(); ++v) {
unsigned w = obj2simplex(v);
objective_term const& objective = m_objectives[v];
// add objective function as row.
coeffs.reset();
vars.reset();
for (unsigned i = 0; i < objective.size(); ++i) {
coeffs.push_back(objective[i].second.to_mpq());
vars.push_back(node2simplex(objective[i].first));
}
coeffs.push_back(mpq(1));
vars.push_back(w);
Simplex::row row = S.add_row(w, vars.size(), vars.c_ptr(), coeffs.c_ptr());
m_objective_rows.push_back(row);
}
}
template<typename Ext>
inf_eps_rational<inf_rational> theory_diff_logic<Ext>::maximize(theory_var v, expr_ref& blocker) {
typedef simplex::simplex<simplex::mpq_ext> Simplex;
Simplex S;
Simplex& S = m_S;
ast_manager& m = get_manager();
update_simplex(S);
objective_term const& objective = m_objectives[v];
TRACE("arith",
@ -1081,55 +1193,6 @@ inf_eps_rational<inf_rational> theory_diff_logic<Ext>::maximize(theory_var v, ex
}
tout << "Free coefficient " << m_objective_consts[v] << "\n";
);
unsigned num_nodes = m_graph.get_num_nodes();
unsigned num_edges = m_graph.get_num_edges();
vector<dl_edge<GExt> > const& es = m_graph.get_all_edges();
S.ensure_var(num_nodes + num_edges + m_objectives.size());
for (unsigned i = 0; i < num_nodes; ++i) {
numeral const& a = m_graph.get_assignment(i);
rational fin = a.get_rational().to_rational();
rational inf = a.get_infinitesimal().to_rational();
mpq_inf q(fin.to_mpq(), inf.to_mpq());
S.set_value(i, q);
}
S.set_lower(get_zero(), mpq_inf(mpq(0), mpq(0)));
S.set_upper(get_zero(), mpq_inf(mpq(0), mpq(0)));
svector<unsigned> vars;
unsynch_mpq_manager mgr;
scoped_mpq_vector coeffs(mgr);
coeffs.push_back(mpq(1));
coeffs.push_back(mpq(-1));
coeffs.push_back(mpq(-1));
vars.resize(3);
for (unsigned i = 0; i < es.size(); ++i) {
dl_edge<GExt> const& e = es[i];
if (e.is_enabled()) {
unsigned base_var = num_nodes + i;
vars[0] = e.get_target();
vars[1] = e.get_source();
vars[2] = base_var;
S.add_row(base_var, 3, vars.c_ptr(), coeffs.c_ptr());
// t - s <= w
// t - s - b = 0, b >= w
numeral const& w = e.get_weight();
rational fin = w.get_rational().to_rational();
rational inf = w.get_infinitesimal().to_rational();
mpq_inf q(fin.to_mpq(),inf.to_mpq());
S.set_upper(base_var, q);
}
}
unsigned w = num_nodes + num_edges + v;
// add objective function as row.
coeffs.reset();
vars.reset();
for (unsigned i = 0; i < objective.size(); ++i) {
coeffs.push_back(objective[i].second.to_mpq());
vars.push_back(objective[i].first);
}
coeffs.push_back(mpq(1));
vars.push_back(w);
Simplex::row row = S.add_row(w, vars.size(), vars.c_ptr(), coeffs.c_ptr());
TRACE("opt", S.display(tout); display(tout););
@ -1141,11 +1204,13 @@ inf_eps_rational<inf_rational> theory_diff_logic<Ext>::maximize(theory_var v, ex
}
TRACE("opt", S.display(tout); );
SASSERT(is_sat != l_false);
unsigned w = obj2simplex(v);
lbool is_fin = S.minimize(w);
switch (is_fin) {
case l_true: {
simplex::mpq_ext::eps_numeral const& val = S.get_value(w);
inf_rational r(-rational(val.first), -rational(val.second));
Simplex::row row = m_objective_rows[v];
TRACE("opt", tout << r << " " << "\n";
S.display_row(tout, row, true););
Simplex::row_iterator it = S.row_begin(row), end = S.row_end(row);
@ -1154,8 +1219,8 @@ inf_eps_rational<inf_rational> theory_diff_logic<Ext>::maximize(theory_var v, ex
core.reset();
for (; it != end; ++it) {
unsigned v = it->m_var;
if (num_nodes <= v && v < num_nodes + num_edges) {
unsigned edge_id = v - num_nodes;
if (is_simplex_edge(v)) {
unsigned edge_id = simplex2edge(v);
literal lit = m_graph.get_explanation(edge_id);
get_context().literal2expr(lit, tmp);
core.push_back(tmp);