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fix bug in optimization where a variable is updated twice

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Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>
This commit is contained in:
Nikolaj Bjorner 2015-07-07 16:01:48 -07:00
parent 940fed16e1
commit d815cf9b7b
4 changed files with 40 additions and 15 deletions
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50
src/smt/theory_arith_aux.h
View file

@ -1321,8 +1321,10 @@ namespace smt {
typename svector<col_entry>::iterator end = c.end_entries();
init_gains(x_j, inc, min_gain, max_gain);
has_shared |= ctx.is_shared(get_enode(x_j));
bool empty_column = true;
for (; it != end; ++it) {
if (it->is_dead()) continue;
empty_column = false;
row const & r = m_rows[it->m_row_id];
theory_var s = r.get_base_var();
numeral const & coeff_ij = r[it->m_row_idx].m_coeff;
@ -1333,7 +1335,6 @@ namespace smt {
}
has_shared |= ctx.is_shared(get_enode(s));
}
bool empty_column = (c.begin_entries() == end);
TRACE("opt",
tout << (safe_gain(min_gain, max_gain)?"safe":"unsafe") << "\n";
tout << "min gain: " << min_gain;
@ -1373,7 +1374,7 @@ namespace smt {
template<typename Ext>
void theory_arith<Ext>::normalize_gain(numeral const& divisor, inf_numeral & max_gain) const {
SASSERT(divisor.is_int());
if (!divisor.is_minus_one() && !divisor.is_one() && !max_gain.is_minus_one()) {
if (!divisor.is_minus_one() && !max_gain.is_minus_one()) {
max_gain = floor(max_gain/divisor)*divisor;
}
}
@ -1401,7 +1402,8 @@ namespace smt {
TRACE("opt",
tout << "v" << x << " := " << get_value(x) << " "
<< "min gain: " << min_gain << " "
<< "max gain: " << max_gain << "\n";);
<< "max gain: " << max_gain << "\n";);
SASSERT(max_gain.is_minus_one() || !max_gain.is_neg());
SASSERT(min_gain.is_minus_one() || min_gain.is_one());
@ -1423,6 +1425,8 @@ namespace smt {
// a_ij < 0, !inc -> decrement x_i
// a_ij denominator
SASSERT(!a_ij.is_zero());
if (!safe_gain(min_gain, max_gain)) return false;
inf_numeral max_inc = inf_numeral::minus_one();
@ -1438,8 +1442,13 @@ namespace smt {
if (is_int(x_i)) den_aij = denominator(a_ij);
SASSERT(den_aij.is_pos() && den_aij.is_int());
if (is_int(x_i) && !den_aij.is_one() && min_gain.is_pos()) {
min_gain = inf_numeral(lcm(min_gain.get_rational(), den_aij));
if (is_int(x_i) && !den_aij.is_one()) {
if (min_gain.is_neg()) {
min_gain = inf_numeral(den_aij);
}
else {
min_gain = inf_numeral(lcm(min_gain.get_rational(), den_aij));
}
normalize_gain(min_gain.get_rational(), max_gain);
}
@ -1467,11 +1476,12 @@ namespace smt {
<< "min gain: " << min_gain << " "
<< "max gain: " << max_gain << " tighter: "
<< (is_tighter?"true":"false") << "\n";);
SASSERT(max_gain.is_minus_one() || !max_gain.is_neg());
SASSERT(min_gain.is_minus_one() || !min_gain.is_neg());
//SASSERT(!is_int(x_i) || min_gain.is_pos());
//SASSERT(!is_int(x_i) || min_gain.is_int());
//SASSERT(!is_int(x_i) || max_gain.is_int());
SASSERT(!is_int(x_i) || min_gain.is_pos());
SASSERT(!is_int(x_i) || min_gain.is_int());
SASSERT(!is_int(x_i) || max_gain.is_int());
return is_tighter;
}
@ -1510,6 +1520,7 @@ namespace smt {
context& ctx = get_context();
SASSERT(!maintain_integrality || valid_assignment());
SASSERT(satisfy_bounds());
numeral a_ij, curr_a_ij, coeff, curr_coeff;
inf_numeral min_gain, max_gain, curr_min_gain, curr_max_gain;
@ -1538,15 +1549,17 @@ namespace smt {
// variable cannot be used for max/min.
continue;
}
if (!pick_var_to_leave(curr_x_j, curr_inc, curr_a_ij,
curr_min_gain, curr_max_gain,
has_shared, curr_x_i)) {
bool picked_var = pick_var_to_leave(curr_x_j, curr_inc, curr_a_ij,
curr_min_gain, curr_max_gain,
has_shared, curr_x_i);
SASSERT(!picked_var || safe_gain(curr_min_gain, curr_max_gain));
if (!picked_var) {
best_efforts++;
}
else {
SASSERT(safe_gain(curr_min_gain, curr_max_gain));
}
if (curr_x_i == null_theory_var) {
else if (curr_x_i == null_theory_var) {
TRACE("opt", tout << "unbounded\n";);
// we can increase/decrease curr_x_j as much as we want.
x_i = null_theory_var; // unbounded
@ -1584,6 +1597,7 @@ namespace smt {
if (x_j == null_theory_var) {
TRACE("opt", tout << "row is " << (max ? "maximized" : "minimized") << "\n";);
SASSERT(!maintain_integrality || valid_assignment());
SASSERT(satisfy_bounds());
result = OPTIMIZED;
break;
}
@ -1599,14 +1613,17 @@ namespace smt {
update_value(x_j, max_gain);
TRACE("opt", tout << "moved v" << x_j << " to upper bound\n";);
SASSERT(!maintain_integrality || valid_assignment());
SASSERT(satisfy_bounds());
continue;
}
if (!inc && lower(x_j)) {
SASSERT(!unbounded_gain(max_gain));
SASSERT(max_gain.is_pos());
max_gain.neg();
update_value(x_j, max_gain);
TRACE("opt", tout << "moved v" << x_j << " to lower bound\n";);
SASSERT(!maintain_integrality || valid_assignment());
SASSERT(satisfy_bounds());
continue;
}
#if 0
@ -1642,6 +1659,7 @@ namespace smt {
}
update_value(x_j, max_gain);
SASSERT(!maintain_integrality || valid_assignment());
SASSERT(satisfy_bounds());
continue;
}
@ -1670,6 +1688,7 @@ namespace smt {
add_tmp_row(r, coeff, r2);
SASSERT(r.get_idx_of(x_j) == -1);
SASSERT(!maintain_integrality || valid_assignment());
SASSERT(satisfy_bounds());
}
TRACE("opt", display(tout););
return (best_efforts>0)?BEST_EFFORT:result;
@ -1749,6 +1768,7 @@ namespace smt {
expr* e = get_enode(v)->get_owner();
SASSERT(!maintain_integrality || valid_assignment());
SASSERT(satisfy_bounds());
SASSERT(!is_quasi_base(v));
if ((max && at_upper(v)) || (!max && at_lower(v))) {
TRACE("opt", tout << "At bound: " << mk_pp(e, get_manager()) << "...\n";);

1
src/smt/theory_arith_core.h
View file

@ -2154,6 +2154,7 @@ namespace smt {
CASSERT("arith", wf_rows());
CASSERT("arith", wf_columns());
CASSERT("arith", valid_row_assignment());
CASSERT("arith", satisfy_bounds());
return true;
}

1
src/smt/theory_arith_inv.h
View file

@ -196,6 +196,7 @@ namespace smt {
CTRACE("bound_bug", below_lower(v) || above_upper(v), display_var(tout, v); display(tout););
SASSERT(!below_lower(v));
SASSERT(!above_upper(v));
if (below_lower(v) || above_upper(v)) return false;
}
return true;
}

3
src/smt/theory_arith_nl.h
View file

@ -2238,6 +2238,9 @@ namespace smt {
m_nl_gb_exhausted = true;
warn = true;
}
if (get_context().get_cancel_flag()) {
return GB_FAIL;
}
TRACE("non_linear_gb", tout << "after:\n"; gb.display(tout););
// Scan the grobner basis eqs, and look for inconsistencies.
eqs.reset();