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fix the merge

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Signed-off-by: Lev Nachmanson <levnach@hotmail.com>
This commit is contained in:
Lev Nachmanson 2019-05-23 03:27:31 -07:00
parent 3b9b4d973b
commit b6513b8e2d
9 changed files with 20 additions and 535 deletions
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2
src/smt/theory_lra.cpp
View file

@ -438,7 +438,7 @@ class theory_lra::imp {
void ensure_nla() {
if (!m_nla) {
m_nla = alloc(nla::solver, *m_solver.get(), m.limit(), ctx().get_params());
m_nla = alloc(nla::solver, *m_solver.get());
m_switcher.m_nla = &m_nla;
for (auto const& _s : m_scopes) {
(void)_s;

3
src/util/lp/CMakeLists.txt
View file

@ -31,7 +31,8 @@ z3_add_component(lp
nla_monotone_lemmas.cpp
nla_order_lemmas.cpp
nla_solver.cpp
nra_solver.cpp
nla_tangent_lemmas.cpp
nra_solver.cpp
permutation_matrix.cpp
random_updater.cpp
row_eta_matrix.cpp

2
src/util/lp/factorization.h
View file

@ -21,11 +21,11 @@
#pragma once
#include "util/rational.h"
#include "util/lp/monomial.h"
#include "util/lp/nla_defs.h"
namespace nla {
struct factorization_factory;
typedef unsigned lpvar;
enum class factor_type { VAR, MON };

1
src/util/lp/lp_types.h
View file

@ -22,4 +22,5 @@ namespace lp {
typedef unsigned var_index;
typedef unsigned constraint_index;
typedef unsigned row_index;
enum lconstraint_kind { LE = -2, LT = -1 , GE = 2, GT = 1, EQ = 0, NE = 3 };
}

537
src/util/lp/nla_core.cpp
View file

@ -215,15 +215,6 @@ std::ostream& core::print_monomial(const monomial& m, std::ostream& out) const {
return out;
}
std::ostream& core::print_point(const point &a, std::ostream& out) const {
out << "(" << a.x << ", " << a.y << ")";
return out;
}
std::ostream& core::print_tangent_domain(const point &a, const point &b, std::ostream& out) const {
out << "("; print_point(a, out); out << ", "; print_point(b, out); out << ")";
return out;
}
std::ostream& core::print_bfc(const factorization& m, std::ostream& out) const {
SASSERT(m.size() == 2);
@ -541,36 +532,7 @@ int core::vars_sign(const svector<lpvar>& v) {
return sign;
}
void core:: negate_strict_sign(lpvar j) {
TRACE("nla_solver_details", print_var(j, tout););
if (!vvr(j).is_zero()) {
int sign = nla::rat_sign(vvr(j));
mk_ineq(j, (sign == 1? llc::LE : llc::GE));
} else { // vvr(j).is_zero()
if (has_lower_bound(j) && get_lower_bound(j) >= rational(0)) {
explain_existing_lower_bound(j);
mk_ineq(j, llc::GT);
} else {
SASSERT(has_upper_bound(j) && get_upper_bound(j) <= rational(0));
explain_existing_upper_bound(j);
mk_ineq(j, llc::LT);
}
}
}
void core:: generate_strict_case_zero_lemma(const monomial& m, unsigned zero_j, int sign_of_zj) {
TRACE("nla_solver_bl", tout << "sign_of_zj = " << sign_of_zj << "\n";);
// we know all the signs
add_empty_lemma();
mk_ineq(zero_j, (sign_of_zj == 1? llc::GT : llc::LT));
for (unsigned j : m){
if (j != zero_j) {
negate_strict_sign(j);
}
}
negate_strict_sign(m.var());
TRACE("nla_solver", print_lemma(tout););
}
bool core:: has_upper_bound(lpvar j) const {
return m_lar_solver.column_has_upper_bound(j);
@ -628,103 +590,6 @@ bool core::sign_contradiction(const monomial& m) const {
}
*/
// Monomials m and n vars have the same values, up to "sign"
// Generate a lemma if values of m.var() and n.var() are not the same up to sign
bool core:: basic_sign_lemma_on_two_monomials(const monomial& m, const monomial& n, const rational& sign) {
if (vvr(m) == vvr(n) *sign)
return false;
TRACE("nla_solver", tout << "sign contradiction:\nm = "; print_monomial_with_vars(m, tout); tout << "n= "; print_monomial_with_vars(n, tout); tout << "sign: " << sign << "\n";);
generate_sign_lemma(m, n, sign);
return true;
}
void core:: basic_sign_lemma_model_based_one_mon(const monomial& m, int product_sign) {
if (product_sign == 0) {
TRACE("nla_solver_bl", tout << "zero product sign\n";);
generate_zero_lemmas(m);
} else {
add_empty_lemma();
for(lpvar j: m) {
negate_strict_sign(j);
}
mk_ineq(m.var(), product_sign == 1? llc::GT : llc::LT);
TRACE("nla_solver", print_lemma(tout); tout << "\n";);
}
}
bool core:: basic_sign_lemma_model_based() {
unsigned i = random() % m_to_refine.size();
unsigned ii = i;
do {
const monomial& m = m_monomials[m_to_refine[i]];
int mon_sign = nla::rat_sign(vvr(m));
int product_sign = rat_sign(m);
if (mon_sign != product_sign) {
basic_sign_lemma_model_based_one_mon(m, product_sign);
if (done())
return true;
}
i++;
if (i == m_to_refine.size())
i = 0;
} while (i != ii);
return m_lemma_vec->size() > 0;
}
bool core:: basic_sign_lemma_on_mon(unsigned i, std::unordered_set<unsigned> & explored){
const monomial& m = m_monomials[i];
TRACE("nla_solver_details", tout << "i = " << i << ", mon = "; print_monomial_with_vars(m, tout););
const index_with_sign& rm_i_s = m_rm_table.get_rooted_mon(i);
unsigned k = rm_i_s.index();
if (!try_insert(k, explored))
return false;
const auto& mons_to_explore = m_rm_table.rms()[k].m_mons;
TRACE("nla_solver", tout << "rm = "; print_rooted_monomial_with_vars(m_rm_table.rms()[k], tout) << "\n";);
for (index_with_sign i_s : mons_to_explore) {
TRACE("nla_solver", tout << "i_s = (" << i_s.index() << "," << i_s.sign() << ")\n";
print_monomial_with_vars(m_monomials[i_s.index()], tout << "m = ") << "\n";
{
for (lpvar j : m_monomials[i_s.index()] ) {
lpvar rj = m_evars.find(j).var();
if (j == rj)
tout << "rj = j =" << j << "\n";
else {
lp::explanation e;
m_evars.explain(j, e);
tout << "j = " << j << ", e = "; print_explanation(e, tout) << "\n";
}
}
}
);
unsigned n = i_s.index();
if (n == i) continue;
if (basic_sign_lemma_on_two_monomials(m, m_monomials[n], rm_i_s.sign()*i_s.sign()))
if(done())
return true;
}
TRACE("nla_solver_details", tout << "return false\n";);
return false;
}
/**
* \brief <generate lemma by using the fact that -ab = (-a)b) and
-ab = a(-b)
*/
bool core:: basic_sign_lemma(bool derived) {
if (!derived)
return basic_sign_lemma_model_based();
std::unordered_set<unsigned> explored;
for (unsigned i : m_to_refine){
if (basic_sign_lemma_on_mon(i, explored))
return true;
}
return false;
}
bool core:: var_is_fixed_to_zero(lpvar j) const {
return
m_lar_solver.column_has_upper_bound(j) &&
@ -872,63 +737,6 @@ bool core:: var_is_separated_from_zero(lpvar j) const {
var_has_positive_lower_bound(j);
}
// x = 0 or y = 0 -> xy = 0
bool core:: basic_lemma_for_mon_non_zero_derived(const rooted_mon& rm, const factorization& f) {
TRACE("nla_solver", trace_print_monomial_and_factorization(rm, f, tout););
if (!var_is_separated_from_zero(var(rm)))
return false;
int zero_j = -1;
for (auto j : f) {
if (var_is_fixed_to_zero(var(j))) {
zero_j = var(j);
break;
}
}
if (zero_j == -1) {
return false;
}
add_empty_lemma();
explain_fixed_var(zero_j);
explain_var_separated_from_zero(var(rm));
explain(rm, current_expl());
TRACE("nla_solver", print_lemma(tout););
return true;
}
// use the fact that
// |xabc| = |x| and x != 0 -> |a| = |b| = |c| = 1
bool core:: basic_lemma_for_mon_neutral_monomial_to_factor_model_based(const rooted_mon& rm, const factorization& f) {
TRACE("nla_solver_bl", trace_print_monomial_and_factorization(rm, f, tout););
lpvar mon_var = m_monomials[rm.orig_index()].var();
TRACE("nla_solver_bl", trace_print_monomial_and_factorization(rm, f, tout); tout << "\nmon_var = " << mon_var << "\n";);
const auto & mv = vvr(mon_var);
const auto abs_mv = abs(mv);
if (abs_mv == rational::zero()) {
return false;
}
lpvar jl = -1;
for (auto j : f ) {
if (abs(vvr(j)) == abs_mv) {
jl = var(j);
break;
}
}
if (jl == static_cast<lpvar>(-1))
return false;
lpvar not_one_j = -1;
for (auto j : f ) {
if (var(j) == jl) {
continue;
}
if (abs(vvr(j)) != rational(1)) {
not_one_j = var(j);
break;
}
}
bool core::vars_are_equiv(lpvar a, lpvar b) const {
SASSERT(abs(val(a)) == abs(val(b)));
@ -947,240 +755,6 @@ void core::explain_equiv_vars(lpvar a, lpvar b) {
}
}
// use the fact that
// |xabc| = |x| and x != 0 -> |a| = |b| = |c| = 1
bool core:: basic_lemma_for_mon_neutral_monomial_to_factor_derived(const rooted_mon& rm, const factorization& f) {
TRACE("nla_solver", trace_print_monomial_and_factorization(rm, f, tout););
lpvar mon_var = m_monomials[rm.orig_index()].var();
TRACE("nla_solver", trace_print_monomial_and_factorization(rm, f, tout); tout << "\nmon_var = " << mon_var << "\n";);
const auto & mv = vvr(mon_var);
const auto abs_mv = abs(mv);
if (abs_mv == rational::zero()) {
return false;
}
bool mon_var_is_sep_from_zero = var_is_separated_from_zero(mon_var);
lpvar jl = -1;
for (auto fc : f ) {
lpvar j = var(fc);
if (abs(vvr(j)) == abs_mv && vars_are_equiv(j, mon_var) &&
(mon_var_is_sep_from_zero || var_is_separated_from_zero(j))) {
jl = j;
break;
}
}
if (jl == static_cast<lpvar>(-1))
return false;
lpvar not_one_j = -1;
for (auto j : f ) {
if (var(j) == jl) {
continue;
}
if (abs(vvr(j)) != rational(1)) {
not_one_j = var(j);
break;
}
}
if (not_one_j == static_cast<lpvar>(-1)) {
return false;
}
add_empty_lemma();
// mon_var = 0
if (mon_var_is_sep_from_zero)
explain_var_separated_from_zero(mon_var);
else
explain_var_separated_from_zero(jl);
explain_equiv_vars(mon_var, jl);
// not_one_j = 1
mk_ineq(not_one_j, llc::EQ, rational(1));
// not_one_j = -1
mk_ineq(not_one_j, llc::EQ, -rational(1));
explain(rm, current_expl());
TRACE("nla_solver", print_lemma(tout); );
return true;
}
// use the fact
// 1 * 1 ... * 1 * x * 1 ... * 1 = x
bool core:: basic_lemma_for_mon_neutral_from_factors_to_monomial_model_based(const rooted_mon& rm, const factorization& f) {
rational sign = rm.orig_sign();
TRACE("nla_solver_bl", tout << "f = "; print_factorization(f, tout); tout << ", sign = " << sign << '\n'; );
lpvar not_one = -1;
for (auto j : f){
TRACE("nla_solver_bl", tout << "j = "; print_factor_with_vars(j, tout););
auto v = vvr(j);
if (v == rational(1)) {
continue;
}
if (v == -rational(1)) {
sign = - sign;
continue;
}
if (not_one == static_cast<lpvar>(-1)) {
not_one = var(j);
continue;
}
// if we are here then there are at least two factors with absolute values different from one : cannot create the lemma
return false;
}
if (not_one + 1) {
// we found the only not_one
if (vvr(rm) == vvr(not_one) * sign) {
TRACE("nla_solver", tout << "the whole equal to the factor" << std::endl;);
return false;
}
} else {
// we have +-ones only in the factorization
if (vvr(rm) == sign) {
return false;
}
}
TRACE("nla_solver_bl", tout << "not_one = " << not_one << "\n";);
add_empty_lemma();
for (auto j : f){
lpvar var_j = var(j);
if (not_one == var_j) continue;
mk_ineq(var_j, llc::NE, j.is_var()? vvr(j) : canonize_sign(j) * vvr(j));
}
if (not_one == static_cast<lpvar>(-1)) {
mk_ineq(m_monomials[rm.orig_index()].var(), llc::EQ, sign);
} else {
mk_ineq(m_monomials[rm.orig_index()].var(), -sign, not_one, llc::EQ);
}
explain(rm, current_expl());
explain(f, current_expl());
TRACE("nla_solver",
print_lemma(tout);
tout << "rm = "; print_rooted_monomial_with_vars(rm, tout);
);
return true;
}
// use the fact
// 1 * 1 ... * 1 * x * 1 ... * 1 = x
bool core:: basic_lemma_for_mon_neutral_from_factors_to_monomial_model_based_fm(const monomial& m) {
lpvar not_one = -1;
rational sign(1);
TRACE("nla_solver_bl", tout << "m = "; print_monomial(m, tout););
for (auto j : m){
auto v = vvr(j);
if (v == rational(1)) {
continue;
}
if (v == -rational(1)) {
sign = - sign;
continue;
}
if (not_one == static_cast<lpvar>(-1)) {
not_one = j;
continue;
}
// if we are here then there are at least two factors with values different from one and minus one: cannot create the lemma
return false;
}
if (not_one + 1) { // we found the only not_one
if (vvr(m) == vvr(not_one) * sign) {
TRACE("nla_solver", tout << "the whole equal to the factor" << std::endl;);
return false;
}
}
add_empty_lemma();
for (auto j : m){
if (not_one == j) continue;
mk_ineq(j, llc::NE, vvr(j));
}
if (not_one == static_cast<lpvar>(-1)) {
mk_ineq(m.var(), llc::EQ, sign);
} else {
mk_ineq(m.var(), -sign, not_one, llc::EQ);
}
TRACE("nla_solver", print_lemma(tout););
return true;
}
// use the fact
// 1 * 1 ... * 1 * x * 1 ... * 1 = x
bool core:: basic_lemma_for_mon_neutral_from_factors_to_monomial_derived(const rooted_mon& rm, const factorization& f) {
return false;
rational sign = rm.orig().m_sign;
lpvar not_one = -1;
TRACE("nla_solver", tout << "f = "; print_factorization(f, tout););
for (auto j : f){
TRACE("nla_solver", tout << "j = "; print_factor_with_vars(j, tout););
auto v = vvr(j);
if (v == rational(1)) {
continue;
}
if (v == -rational(1)) {
sign = - sign;
continue;
}
if (not_one == static_cast<lpvar>(-1)) {
not_one = var(j);
continue;
}
// if we are here then there are at least two factors with values different from one and minus one: cannot create the lemma
return false;
}
add_empty_lemma();
explain(rm, current_expl());
for (auto j : f){
lpvar var_j = var(j);
if (not_one == var_j) continue;
mk_ineq(var_j, llc::NE, j.is_var()? vvr(j) : canonize_sign(j) * vvr(j));
}
if (not_one == static_cast<lpvar>(-1)) {
mk_ineq(m_monomials[rm.orig_index()].var(), llc::EQ, sign);
} else {
mk_ineq(m_monomials[rm.orig_index()].var(), -sign, not_one, llc::EQ);
}
TRACE("nla_solver",
tout << "rm = "; print_rooted_monomial_with_vars(rm, tout);
print_lemma(tout););
return true;
}
void core::basic_lemma_for_mon_neutral_model_based(const rooted_mon& rm, const factorization& f) {
if (f.is_mon()) {
basic_lemma_for_mon_neutral_monomial_to_factor_model_based_fm(*f.mon());
basic_lemma_for_mon_neutral_from_factors_to_monomial_model_based_fm(*f.mon());
}
else {
basic_lemma_for_mon_neutral_monomial_to_factor_model_based(rm, f);
basic_lemma_for_mon_neutral_from_factors_to_monomial_model_based(rm, f);
}
}
bool core:: basic_lemma_for_mon_neutral_derived(const rooted_mon& rm, const factorization& factorization) {
return
basic_lemma_for_mon_neutral_monomial_to_factor_derived(rm, factorization) ||
basic_lemma_for_mon_neutral_from_factors_to_monomial_derived(rm, factorization);
return false;
}
void core::explain(const factorization& f, lp::explanation& exp) {
SASSERT(!f.is_mon());
for (const auto& fc : f) {
@ -1310,6 +884,16 @@ void core::init_vars_equivalence() {
collect_equivs();
// SASSERT(tables_are_ok());
}
bool core::vars_table_is_ok() const {
// return m_var_eqs.is_ok();
return true;
}
bool core::rm_table_is_ok() const {
// return m_emons.is_ok();
return true;
}
bool core:: tables_are_ok() const {
return vars_table_is_ok() && rm_table_is_ok();
@ -1636,28 +1220,6 @@ void core::add_empty_lemma() {
m_lemma_vec->push_back(lemma());
}
void core::generate_tang_plane(const rational & a, const rational& b, const factor& x, const factor& y, bool below, lpvar j, const rational& j_sign) {
lpvar jx = var(x);
lpvar jy = var(y);
add_empty_lemma();
negate_relation(jx, a);
negate_relation(jy, b);
bool sbelow = j_sign.is_pos()? below: !below;
#if Z3DEBUG
int mult_sign = nla::rat_sign(a - vvr(jx))*nla::rat_sign(b - vvr(jy));
SASSERT((mult_sign == 1) == sbelow);
// If "mult_sign is 1" then (a - x)(b-y) > 0 and ab - bx - ay + xy > 0
// or -ab + bx + ay < xy or -ay - bx + xy > -ab
// j_sign*vvr(j) stands for xy. So, finally we have -ay - bx + j_sign*j > - ab
#endif
lp::lar_term t;
t.add_coeff_var(-a, jy);
t.add_coeff_var(-b, jx);
t.add_coeff_var( j_sign, j);
mk_ineq(t, sbelow? llc::GT : llc::LT, - a*b);
}
void core::negate_relation(unsigned j, const rational& a) {
SASSERT(val(j) != a);
if (val(j) < a) {
@ -1667,85 +1229,6 @@ void core::negate_relation(unsigned j, const rational& a) {
mk_ineq(j, llc::LE, a);
}
}
void core::generate_two_tang_lines(const bfc & bf, const point& xy, const rational& sign, lpvar j) {
add_empty_lemma();
mk_ineq(var(bf.m_x), llc::NE, xy.x);
mk_ineq(sign, j, - xy.x, var(bf.m_y), llc::EQ);
add_empty_lemma();
mk_ineq(var(bf.m_y), llc::NE, xy.y);
mk_ineq(sign, j, - xy.y, var(bf.m_x), llc::EQ);
}
// Get two planes tangent to surface z = xy, one at point a, and another at point b.
// One can show that these planes still create a cut.
void core::get_initial_tang_points(point &a, point &b, const point& xy,
bool below) const {
const rational& x = xy.x;
const rational& y = xy.y;
if (!below){
a = point(x - rational(1), y + rational(1));
b = point(x + rational(1), y - rational(1));
}
else {
a = point(x - rational(1), y - rational(1));
b = point(x + rational(1), y + rational(1));
}
}
void core::push_tang_point(point &a, const point& xy, bool below, const rational& correct_val, const rational& val) const {
SASSERT(correct_val == xy.x * xy.y);
int steps = 10;
point del = a - xy;
while (steps--) {
del *= rational(2);
point na = xy + del;
TRACE("nla_solver", tout << "del = "; print_point(del, tout); tout << std::endl;);
if (!plane_is_correct_cut(na, xy, correct_val, val, below)) {
TRACE("nla_solver_tp", tout << "exit";tout << std::endl;);
return;
}
a = na;
}
}
void core::push_tang_points(point &a, point &b, const point& xy, bool below, const rational& correct_val, const rational& val) const {
push_tang_point(a, xy, below, correct_val, val);
push_tang_point(b, xy, below, correct_val, val);
}
rational core::tang_plane(const point& a, const point& x) const {
return a.x * x.y + a.y * x.x - a.x * a.y;
}
bool core:: plane_is_correct_cut(const point& plane,
const point& xy,
const rational & correct_val,
const rational & val,
bool below) const {
SASSERT(correct_val == xy.x * xy.y);
if (below && val > correct_val) return false;
rational sign = below? rational(1) : rational(-1);
rational px = tang_plane(plane, xy);
return ((correct_val - px)*sign).is_pos() && !((px - val)*sign).is_neg();
}
// "below" means that the val is below the surface xy
void core::get_tang_points(point &a, point &b, bool below, const rational& val,
const point& xy) const {
get_initial_tang_points(a, b, xy, below);
auto correct_val = xy.x * xy.y;
TRACE("nla_solver", tout << "xy = "; print_point(xy, tout); tout << ", correct val = " << xy.x * xy.y;
tout << "\ntang points:"; print_tangent_domain(a, b, tout);tout << std::endl;);
TRACE("nla_solver", tout << "tang_plane(a, xy) = " << tang_plane(a, xy) << " , val = " << val;
tout << "\ntang_plane(b, xy) = " << tang_plane(b, xy); tout << std::endl;);
SASSERT(plane_is_correct_cut(a, xy, correct_val, val, below));
SASSERT(plane_is_correct_cut(b, xy, correct_val, val, below));
push_tang_points(a, b, xy, below, correct_val, val);
TRACE("nla_solver", tout << "pushed a = "; print_point(a, tout); tout << "\npushed b = "; print_point(b, tout); tout << std::endl;);
}
bool core:: conflict_found() const {
for (const auto & l : * m_lemma_vec) {

4
src/util/lp/nla_solver.cpp
View file

@ -50,8 +50,8 @@ void solver::pop(unsigned n) {
}
solver::solver(lp::lar_solver& s, reslimit& lim, params_ref const& p) {
m_core = alloc(core, s, lim, p);
solver::solver(lp::lar_solver& s) {
m_core = alloc(core, s);
}
solver::~solver() {

2
src/util/lp/nla_solver.h
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@ -34,7 +34,7 @@ class solver {
public:
void add_monomial(lp::var_index v, unsigned sz, lp::var_index const* vs);
solver(lp::lar_solver& s, reslimit& lim, params_ref const& p);
solver(lp::lar_solver& s);
~solver();
inline core * get_core() { return m_core; }
void push();

2
src/util/lp/ul_pair.h
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@ -24,10 +24,10 @@ Revision History:
#include <algorithm>
#include <utility>
#include "util/lp/column_info.h"
#include "util/lp/lp_types.h"
namespace lp {
enum lconstraint_kind { LE = -2, LT = -1 , GE = 2, GT = 1, EQ = 0, NE = 3 };
inline bool kind_is_strict(lconstraint_kind kind) { return kind == LT || kind == GT;}

2
src/util/lp/var_eqs.h
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@ -20,7 +20,7 @@
#pragma once
#include "util/union_find.h"
#include "util/lp/lp_types.h"
#include "util/lp/nla_defs.h"
#include "util/rational.h"
#include "util/lp/explanation.h"
#include "util/lp/incremental_vector.h"