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fix and coallesce clique functionality

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Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>
This commit is contained in:
Nikolaj Bjorner 2016-11-19 03:55:48 -08:00
parent 1600823435
commit ea601dd403
17 changed files with 361 additions and 119 deletions
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75
src/sat/sat_solver.cpp
View file

@ -21,6 +21,7 @@ Revision History:
#include"luby.h"
#include"trace.h"
#include"sat_bceq.h"
#include"max_cliques.h"
// define to update glue during propagation
#define UPDATE_GLUE
@ -3062,74 +3063,44 @@ namespace sat {
//
// -----------------------
struct neg_literal {
unsigned negate(unsigned idx) {
return (~to_literal(idx)).index();
}
};
lbool solver::find_mutexes(literal_vector const& lits, vector<literal_vector> & mutexes) {
literal_vector ps(lits);
max_cliques<neg_literal> mc;
m_user_bin_clauses.reset();
m_binary_clause_graph.reset();
collect_bin_clauses(m_user_bin_clauses, true);
collect_bin_clauses(m_user_bin_clauses, false);
hashtable<literal_pair, pair_hash<literal_hash, literal_hash>, default_eq<literal_pair> > seen_bc;
for (unsigned i = 0; i < m_user_bin_clauses.size(); ++i) {
literal l1 = m_user_bin_clauses[i].first;
literal l2 = m_user_bin_clauses[i].second;
m_binary_clause_graph.reserve(l1.index() + 1);
m_binary_clause_graph.reserve(l2.index() + 1);
m_binary_clause_graph.reserve((~l1).index() + 1);
m_binary_clause_graph.reserve((~l2).index() + 1);
m_binary_clause_graph[l1.index()].push_back(l2);
m_binary_clause_graph[l2.index()].push_back(l1);
literal_pair p(l1, l2);
if (!seen_bc.contains(p)) {
seen_bc.insert(p);
mc.add_edge(l1.index(), l2.index());
}
}
vector<unsigned_vector> _mutexes;
unsigned_vector ps;
for (unsigned i = 0; i < lits.size(); ++i) {
m_binary_clause_graph.reserve(lits[i].index() + 1);
m_binary_clause_graph.reserve((~lits[i]).index() + 1);
ps.push_back(lits[i].index());
}
bool non_empty = true;
m_seen[0].reset();
while (non_empty) {
literal_vector mutex;
bool turn = false;
m_reachable[turn] = ps;
while (!m_reachable[turn].empty()) {
literal p = m_reachable[turn].pop();
if (m_seen[0].contains(p)) {
continue;
}
m_reachable[turn].remove(p);
m_seen[0].insert(p);
mutex.push_back(p);
if (m_reachable[turn].empty()) {
break;
}
m_reachable[!turn].reset();
get_reachable(p, m_reachable[turn], m_reachable[!turn]);
turn = !turn;
mc.cliques(ps, _mutexes);
for (unsigned i = 0; i < _mutexes.size(); ++i) {
literal_vector lits;
for (unsigned j = 0; j < _mutexes[i].size(); ++j) {
lits.push_back(to_literal(_mutexes[i][j]));
}
if (mutex.size() > 1) {
mutexes.push_back(mutex);
}
non_empty = !mutex.empty();
mutexes.push_back(lits);
}
return l_true;
}
void solver::get_reachable(literal p, literal_set const& goal, literal_set& reachable) {
m_seen[1].reset();
m_todo.reset();
m_todo.push_back(p);
while (!m_todo.empty()) {
p = m_todo.back();
m_todo.pop_back();
if (m_seen[1].contains(p)) {
continue;
}
m_seen[1].insert(p);
literal np = ~p;
if (goal.contains(np)) {
reachable.insert(np);
}
m_todo.append(m_binary_clause_graph[np.index()]);
}
}
// -----------------------
//
// Consequence generation.

5
src/sat/sat_solver.h
View file

@ -451,14 +451,9 @@ namespace sat {
u_map<index_set> m_antecedents;
vector<literal_vector> m_binary_clause_graph;
literal_set m_reachable[2];
literal_set m_seen[2];
literal_vector m_todo;
void extract_assumptions(literal lit, index_set& s);
void get_reachable(literal p, literal_set const& goal, literal_set& reachable);
lbool get_consequences(literal_vector const& assms, literal_vector const& lits, vector<literal_vector>& conseq);
void delete_unfixed(literal_set& unfixed);

1
src/sat/sat_types.h
View file

@ -96,6 +96,7 @@ namespace sat {
};
const literal null_literal;
struct literal_hash : obj_hash<literal> {};
inline literal to_literal(unsigned x) { return literal(x); }
inline bool operator<(literal const & l1, literal const & l2) { return l1.m_val < l2.m_val; }