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stellensatz2 showing signs of life

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Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>
This commit is contained in:
Nikolaj Bjorner 2026-01-21 20:44:38 -08:00
parent f77fd30b8c
commit 2bb5829c1b
3 changed files with 74 additions and 28 deletions
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3
src/math/interval/interval_def.h
View file

@ -1214,8 +1214,9 @@ void interval_manager<C>::mul(interval const & i1, interval const & i2, interval
m().swap(upper(r), new_u_val);
set_lower_is_inf(r, new_l_kind == EN_MINUS_INFINITY);
set_upper_is_inf(r, new_u_kind == EN_PLUS_INFINITY);
SASSERT(!(i1_contains_zero || i2_contains_zero) || contains_zero(r));
TRACE(interval_bug, tout << "result: "; display(tout, r); tout << "\n";);
SASSERT(!(i1_contains_zero || i2_contains_zero) || contains_zero(r));
#ifdef _TRACE
call_id++;
#endif

96
src/math/lp/nla_stellensatz2.cpp
View file

@ -87,6 +87,10 @@ namespace nla {
m_di(m_dm, core->reslim()) {
}
stellensatz2::~stellensatz2() {
reset();
}
lbool stellensatz2::saturate() {
unsigned num_conflicts = 0;
init_solver();
@ -131,10 +135,9 @@ namespace nla {
return r;
}
void stellensatz2::init_solver() {
void stellensatz2::reset() {
m_num_scopes = 0;
m_monomial_factory.reset();
m_coi.init();
m_values.reset();
while (!m_constraints.empty()) {
m_constraints.pop_back();
@ -143,7 +146,12 @@ namespace nla {
pop_bound();
pop_propagation(m_bounds.size());
}
m_constraint_index.reset();
m_constraint_index.reset();
}
void stellensatz2::init_solver() {
reset();
m_coi.init();
init_vars();
simplify();
}
@ -584,19 +592,26 @@ namespace nla {
//
bool stellensatz2::backtrack(svector<lp::constraint_index> const &core) {
// reset_bounds();
SASSERT(well_formed());
m_constraints_in_conflict.reset();
svector<lp::constraint_index> external, assumptions;
for (auto ci : core)
explain_constraint(ci, external, assumptions);
TRACE(arith, display(tout << "backtrack core " << core << "external " << external << " assumptions " << assumptions << "\n"));
TRACE(arith, display(tout << "backtrack core " << core << "external " << external << " assumptions " << assumptions << "\n");
for (auto a : assumptions)
display_constraint(tout, a);
);
if (assumptions.empty())
return false;
lp::constraint_index max_ci = 0;
for (auto ci : assumptions)
for (auto ci : assumptions)
max_ci = std::max(ci, max_ci);
assumptions.erase(max_ci);
SASSERT(all_of(assumptions, [&](lp::constraint_index ci) { return m_levels[ci] < m_levels[max_ci]; }));
external.append(assumptions);
backtrack(max_ci, external);
SASSERT(well_formed());
return true;
}
@ -1099,14 +1114,19 @@ namespace nla {
propagation_level = std::max(propagation_level, m_levels[ci]);
m_constraint_index.erase({p.index(), k});
TRACE(arith, display_constraint(tout, ci) << "deps: " << deps << " level " << propagation_level << "\n");
TRACE(arith, for (auto d : deps) display_constraint(tout << " dep: ", d););
SASSERT(propagation_level <= m_levels[ci]);
// propagate negated constraint
m_constraints[ci] = negate_constraint(m_constraints[ci]);
m_justifications[ci] = propagation_justification(deps);
m_num_scopes = m_levels[ci] - 1;
m_levels[ci] = propagation_level;
m_num_scopes = propagation_level;
lp::constraint_index head = ci + 1, tail = ci + 1;
// replay other constraints
unsigned sz = m_constraints.size();
// non-chronological backtracking breaks several assumptions that hold for chronological
// The last decision
svector<lp::constraint_index> tail2head;
tail2head.resize(sz - ci);
auto translate_ci = [&](lp::constraint_index old_ci) -> lp::constraint_index {
@ -1114,11 +1134,13 @@ namespace nla {
return old_ci < ci ? old_ci : tail2head[sz - old_ci];
};
for (; tail < m_constraints.size(); ++tail) {
auto [p, k] = m_constraints[tail];
auto level = m_levels[tail];
m_constraint_index.erase({p.index(), k});
if (level > m_num_scopes)
continue;
TRACE(arith, display_constraint(tout << "replaying " << tail << " " << m_num_scopes << "\n", tail));
m_constraints[head] = m_constraints[tail];
m_justifications[head] = translate_j(translate_ci, m_justifications[tail]);
m_levels[head] = is_decision(head) ? ++m_num_scopes : get_level(m_justifications[tail]);
@ -1508,6 +1530,20 @@ namespace nla {
for (unsigned i = 0; i < m_constraints.size(); ++i)
if (!well_formed_bound(i))
return false;
unsigned level = 1;
for (lp::constraint_index i = 0; i < m_constraints.size(); ++i) {
if (is_decision(i)) {
CTRACE(arith, level != m_levels[i], tout << "level of " << i << " should be " << level << "\n";
display_constraint(tout, i));
if (level != m_levels[i])
return false;
++level;
}
}
if (m_num_scopes + 1 != level) {
TRACE(arith, tout << "num scopes set to " << m_num_scopes << " but there are " << level -1 << " decisions\n");
return false;
}
return true;
}
@ -1662,7 +1698,7 @@ namespace nla {
auto [inf, sup, conflict, lo, hi] = find_bounds(v);
CTRACE(arith, inf != lp::null_ci || sup != lp::null_ci || conflict != lp::null_ci,
tout << "bounds for v" << v << " @ " << m_var2level[v] << "\n";
tout << "bounds for v" << v << " @" << m_var2level[v] << "\n";
display_constraint(tout << "lo: ", inf);
display_constraint(tout << "hi: ", sup);
display_constraint(tout << "conflict: ", conflict));
@ -1676,7 +1712,7 @@ namespace nla {
if (!constraint_is_false(inf) && !constraint_is_false(sup))
return lp::null_ci;
TRACE(arith, tout << "v" << v << " @ " << m_var2level[v] << "\n");
TRACE(arith, tout << "v" << v << " @" << m_var2level[v] << "\n");
bool strict_lo = inf != lp::null_ci && m_constraints[inf].k == lp::lconstraint_kind::GT;
bool strict_hi = sup != lp::null_ci && m_constraints[sup].k == lp::lconstraint_kind::GT;
@ -1878,7 +1914,7 @@ namespace nla {
for (unsigned ci = 0; ci < m_constraints.size(); ++ci)
display_constraint(out, ci);
// return out;
return out;
// Display propagation data structures
out << "\n=== Propagation State ===\n";
@ -1997,7 +2033,7 @@ namespace nla {
bool is_true = constraint_is_true(ci);
auto const &[p, k] = m_constraints[ci];
auto level = m_levels[ci];
display_constraint(out << "(" << ci << ") @ " << level << ": ", m_constraints[ci])
display_constraint(out << "(" << ci << ") @" << level << ": ", m_constraints[ci])
<< (is_true ? " [true] " : " [false] ") << "(" << value(p) << " " << k << " 0)\n";
auto const &j = m_justifications[ci];
return display(out << "\t<- ", j) << "\n";
@ -2276,13 +2312,10 @@ namespace nla {
m_prop_qhead = s.qhead;
m_scopes.pop_back();
}
void stellensatz2::propagate() {
while (m_prop_qhead < m_polynomial_queue.size()) {
auto p = m_polynomial_queue[m_prop_qhead++];
propagate_intervals(p);
}
while (m_prop_qhead < m_polynomial_queue.size() && !is_conflict() && c().reslim().inc())
propagate_intervals(m_polynomial_queue[m_prop_qhead++]);
}
bool stellensatz2::is_better(dep_interval const &new_iv, dep_interval const &old_iv) {
@ -2318,6 +2351,7 @@ namespace nla {
bool stellensatz2::update_interval(dep_interval const &new_iv, dd::pdd const &p) {
SASSERT(!p.is_val());
// SASSERT(!m_di.is_empty(new_iv));
auto &old_iv = get_interval(p);
if (!is_better(new_iv, old_iv))
@ -2330,17 +2364,12 @@ namespace nla {
}
void stellensatz2::propagate_intervals(dd::pdd const &p) {
// for each parent of p, propagate updated intervals
m_parents.reserve(p.index() + 1);
for (auto parent : m_parents[p.index()]) {
SASSERT(!parent.is_val());
scoped_dep_interval new_iv(m_di);
auto &x = get_interval(pddm.mk_var(parent.var()));
auto &lo = get_interval(parent.lo());
auto &hi = get_interval(parent.hi());
calculate_interval(new_iv, x, lo, hi);
if (update_interval(new_iv, parent))
m_polynomial_queue.push_back(parent);
auto const &ivp = get_interval(p);
if (m_di.is_empty(ivp)) {
m_conflict_dep.reset();
m_dm.linearize(ivp.m_lower_dep, m_conflict_dep);
m_dm.linearize(ivp.m_upper_dep, m_conflict_dep);
return;
}
// check constraints
@ -2367,5 +2396,18 @@ namespace nla {
propagate_constraint(x, k, value, ci, cs);
}
// for each parent of p, propagate updated intervals
m_parents.reserve(p.index() + 1);
for (auto parent : m_parents[p.index()]) {
SASSERT(!parent.is_val());
scoped_dep_interval new_iv(m_di);
auto &x = get_interval(pddm.mk_var(parent.var()));
auto &lo = get_interval(parent.lo());
auto &hi = get_interval(parent.hi());
calculate_interval(new_iv, x, lo, hi);
if (update_interval(new_iv, parent))
m_polynomial_queue.push_back(parent);
}
}
}

3
src/math/lp/nla_stellensatz2.h
View file

@ -241,6 +241,8 @@ namespace nla {
bool is_decision(justification const& j) const { return std::holds_alternative<assumption_justification>(j); }
bool is_decision(lp::constraint_index ci) const { return is_decision(m_justifications[ci]); }
void reset();
indexed_uint_set m_tabu;
unsigned_vector m_var2level, m_level2var;
@ -458,6 +460,7 @@ namespace nla {
public:
stellensatz2(core* core);
~stellensatz2();
lbool saturate();
void updt_params(params_ref const &p);