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fix #2613 fix #2612

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Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>
This commit is contained in:
Nikolaj Bjorner 2019-10-05 16:57:51 -07:00
parent 016732aa59
commit 39edf73e78
16 changed files with 222 additions and 162 deletions
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45
src/nlsat/nlsat_evaluator.cpp
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@ -43,7 +43,7 @@ namespace nlsat {
svector<section> m_sections;
unsigned_vector m_sorted_sections; // refs to m_sections
unsigned_vector m_poly_sections; // refs to m_sections
svector<int> m_poly_signs;
svector<polynomial::sign> m_poly_signs;
struct poly_info {
unsigned m_num_roots;
unsigned m_first_section; // idx in m_poly_sections;
@ -149,18 +149,18 @@ namespace nlsat {
\brief Add polynomial with the given roots and signs.
*/
unsigned_vector p_section_ids;
void add(anum_vector & roots, svector<int> & signs) {
void add(anum_vector & roots, svector<polynomial::sign> & signs) {
p_section_ids.reset();
if (!roots.empty())
merge(roots, p_section_ids);
unsigned first_sign = m_poly_signs.size();
unsigned first_section = m_poly_sections.size();
unsigned num_signs = signs.size();
unsigned num_poly_signs = signs.size();
// Must normalize signs since we use arithmetic operations such as *
// during evaluation.
// Without normalization, overflows may happen, and wrong results may be produced.
for (unsigned i = 0; i < num_signs; i++)
m_poly_signs.push_back(normalize_sign(signs[i]));
for (unsigned i = 0; i < num_poly_signs; i++)
m_poly_signs.push_back(signs[i]);
m_poly_sections.append(p_section_ids);
m_info.push_back(poly_info(roots.size(), first_section, first_sign));
SASSERT(check_invariant());
@ -169,10 +169,10 @@ namespace nlsat {
/**
\brief Add constant polynomial
*/
void add_const(int sign) {
void add_const(polynomial::sign sign) {
unsigned first_sign = m_poly_signs.size();
unsigned first_section = m_poly_sections.size();
m_poly_signs.push_back(normalize_sign(sign));
m_poly_signs.push_back(sign);
m_info.push_back(poly_info(0, first_section, first_sign));
}
@ -226,12 +226,12 @@ namespace nlsat {
}
// Return the sign idx of pinfo
int sign(poly_info const & pinfo, unsigned i) const {
polynomial::sign sign(poly_info const & pinfo, unsigned i) const {
return m_poly_signs[pinfo.m_first_sign + i];
}
#define LINEAR_SEARCH_THRESHOLD 8
int sign_at(unsigned info_id, unsigned c) const {
polynomial::sign sign_at(unsigned info_id, unsigned c) const {
poly_info const & pinfo = m_info[info_id];
unsigned num_roots = pinfo.m_num_roots;
if (num_roots < LINEAR_SEARCH_THRESHOLD) {
@ -239,7 +239,7 @@ namespace nlsat {
for (; i < num_roots; i++) {
unsigned section_cell_id = cell_id(pinfo, i);
if (section_cell_id == c)
return 0;
return polynomial::sign_zero;
else if (section_cell_id > c)
break;
}
@ -253,7 +253,7 @@ namespace nlsat {
if (c < root_1_cell_id)
return sign(pinfo, 0);
else if (c == root_1_cell_id || c == root_n_cell_id)
return 0;
return polynomial::sign_zero;
else if (c > root_n_cell_id)
return sign(pinfo, num_roots);
int low = 0;
@ -272,7 +272,7 @@ namespace nlsat {
SASSERT(low < mid && mid < high);
unsigned mid_cell_id = cell_id(pinfo, mid);
if (mid_cell_id == c) {
return 0;
return polynomial::sign_zero;
}
if (c < mid_cell_id) {
high = mid;
@ -319,7 +319,7 @@ namespace nlsat {
for (unsigned j = 0; j < num_cells(); j++) {
if (j > 0)
out << " ";
int s = sign_at(i, j);
auto s = sign_at(i, j);
if (s < 0) out << "-";
else if (s == 0) out << "0";
else out << "+";
@ -381,11 +381,10 @@ namespace nlsat {
\pre All variables of p are assigned in the current interpretation.
*/
int eval_sign(poly * p) {
polynomial::sign eval_sign(poly * p) {
// TODO: check if it is useful to cache results
SASSERT(m_assignment.is_assigned(max_var(p)));
int r = m_am.eval_sign_at(polynomial_ref(p, m_pm), m_assignment);
return r > 0 ? +1 : (r < 0 ? -1 : 0);
return m_am.eval_sign_at(polynomial_ref(p, m_pm), m_assignment);
}
bool satisfied(int sign, atom::kind k) {
@ -450,7 +449,7 @@ namespace nlsat {
return a->is_ineq_atom() ? eval_ineq(to_ineq_atom(a), neg) : eval_root(to_root_atom(a), neg);
}
svector<int> m_add_signs_tmp;
svector<polynomial::sign> m_add_signs_tmp;
void add(poly * p, var x, sign_table & t) {
SASSERT(m_pm.max_var(p) <= x);
if (m_pm.max_var(p) < x) {
@ -459,7 +458,7 @@ namespace nlsat {
else {
// isolate roots of p
scoped_anum_vector & roots = m_add_roots_tmp;
svector<int> & signs = m_add_signs_tmp;
svector<polynomial::sign> & signs = m_add_signs_tmp;
roots.reset();
signs.reset();
TRACE("nlsat_evaluator", tout << "x: " << x << " max_var(p): " << m_pm.max_var(p) << "\n";);
@ -471,18 +470,18 @@ namespace nlsat {
}
// Evaluate the sign of p1^e1*...*pn^en (of atom a) in cell c of table t.
int sign_at(ineq_atom * a, sign_table const & t, unsigned c) const {
int sign = 1;
polynomial::sign sign_at(ineq_atom * a, sign_table const & t, unsigned c) const {
auto sign = polynomial::sign_pos;
unsigned num_ps = a->size();
for (unsigned i = 0; i < num_ps; i++) {
int curr_sign = t.sign_at(i, c);
polynomial::sign curr_sign = t.sign_at(i, c);
TRACE("nlsat_evaluator_bug", tout << "sign of i: " << i << " at cell " << c << "\n";
m_pm.display(tout, a->p(i));
tout << "\nsign: " << curr_sign << "\n";);
if (a->is_even(i) && curr_sign < 0)
curr_sign = 1;
curr_sign = polynomial::sign_pos;
sign = sign * curr_sign;
if (sign == 0)
if (sign == polynomial::sign_zero)
break;
}
return sign;