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Merge pull request #1700 from agurfinkel/deep_space

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Deep space
This commit is contained in:
Nikolaj Bjorner 2018-06-24 19:13:34 -07:00 • committed by GitHub
commit a5f4980c92
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7 changed files with 910 additions and 590 deletions
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2
src/muz/spacer/spacer_iuc_proof.h
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@ -33,7 +33,7 @@ public:
bool is_h_marked(proof* p) {return m_h_mark.is_marked(p);} bool is_h_marked(proof* p) {return m_h_mark.is_marked(p);}
bool is_b_pure (proof *p) { bool is_b_pure (proof *p) {
return !is_h_marked (p) && is_core_pure(m.get_fact (p)); return !is_h_marked(p) && !this->is_a_marked(p) && is_core_pure(m.get_fact(p));
} }
void display_dot(std::ostream &out); void display_dot(std::ostream &out);

34
src/muz/spacer/spacer_iuc_solver.cpp
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@ -322,6 +322,24 @@ void iuc_solver::get_iuc(expr_ref_vector &core)
// -- new hypothesis reducer // -- new hypothesis reducer
else else
{ {
#if 0
static unsigned bcnt = 0;
{
bcnt++;
TRACE("spacer", tout << "Dumping pf bcnt: " << bcnt << "\n";);
if (bcnt == 123) {
std::ofstream ofs;
ofs.open("/tmp/bpf_" + std::to_string(bcnt) + ".dot");
iuc_proof iuc_pf_before(m, res.get(), core_lits);
iuc_pf_before.display_dot(ofs);
ofs.close();
proof_checker pc(m);
expr_ref_vector side(m);
ENSURE(pc.check(res, side));
}
}
#endif
scoped_watch _t_ (m_hyp_reduce2_sw); scoped_watch _t_ (m_hyp_reduce2_sw);
// pre-process proof for better iuc extraction // pre-process proof for better iuc extraction
@ -356,6 +374,22 @@ void iuc_solver::get_iuc(expr_ref_vector &core)
iuc_proof iuc_pf(m, res, core_lits); iuc_proof iuc_pf(m, res, core_lits);
#if 0
static unsigned cnt = 0;
{
cnt++;
TRACE("spacer", tout << "Dumping pf cnt: " << cnt << "\n";);
if (cnt == 123) {
std::ofstream ofs;
ofs.open("/tmp/pf_" + std::to_string(cnt) + ".dot");
iuc_pf.display_dot(ofs);
ofs.close();
proof_checker pc(m);
expr_ref_vector side(m);
ENSURE(pc.check(res, side));
}
}
#endif
unsat_core_learner learner(m, iuc_pf); unsat_core_learner learner(m, iuc_pf);
unsat_core_plugin* plugin; unsat_core_plugin* plugin;

1165
src/muz/spacer/spacer_proof_utils.cpp
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File diff suppressed because it is too large Load diff

36
src/muz/spacer/spacer_unsat_core_learner.cpp
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@ -36,28 +36,27 @@ void unsat_core_learner::register_plugin(unsat_core_plugin* plugin) {
} }
void unsat_core_learner::compute_unsat_core(expr_ref_vector& unsat_core) { void unsat_core_learner::compute_unsat_core(expr_ref_vector& unsat_core) {
// traverse proof
proof_post_order it(m_pr.get(), m); proof_post_order it(m_pr.get(), m);
while (it.hasNext()) { while (it.hasNext()) {
proof* currentNode = it.next(); proof* curr = it.next();
if (m.get_num_parents(currentNode) > 0) { bool done = is_closed(curr);
bool need_to_mark_closed = true; if (done) continue;
for (proof* premise : m.get_parents(currentNode)) { if (m.get_num_parents(curr) > 0) {
need_to_mark_closed &= (!m_pr.is_b_marked(premise) || m_closed.is_marked(premise)); done = true;
} for (proof* p : m.get_parents(curr)) done &= !is_b_open(p);
set_closed(curr, done);
// save result
m_closed.mark(currentNode, need_to_mark_closed);
} }
// we have now collected all necessary information, so we can visit the node // we have now collected all necessary information,
// if the node mixes A-reasoning and B-reasoning and contains non-closed premises // so we can visit the node
if (m_pr.is_a_marked(currentNode) && // if the node mixes A-reasoning and B-reasoning
m_pr.is_b_marked(currentNode) && // and contains non-closed premises
!m_closed.is_marked(currentNode)) { if (!done) {
compute_partial_core(currentNode); // then we need to compute a partial core if (is_a(curr) && is_b(curr)) {
compute_partial_core(curr);
}
} }
} }
@ -74,7 +73,7 @@ void unsat_core_learner::compute_unsat_core(expr_ref_vector& unsat_core) {
void unsat_core_learner::compute_partial_core(proof* step) { void unsat_core_learner::compute_partial_core(proof* step) {
for (unsat_core_plugin* plugin : m_plugins) { for (unsat_core_plugin* plugin : m_plugins) {
if (m_closed.is_marked(step)) break; if (is_closed(step)) break;
plugin->compute_partial_core(step); plugin->compute_partial_core(step);
} }
} }
@ -93,9 +92,6 @@ void unsat_core_learner::set_closed(proof* p, bool value) {
m_closed.mark(p, value); m_closed.mark(p, value);
} }
bool unsat_core_learner::is_b_open(proof *p) {
return m_pr.is_b_marked(p) && !is_closed (p);
}
void unsat_core_learner::add_lemma_to_core(expr* lemma) { void unsat_core_learner::add_lemma_to_core(expr* lemma) {
m_unsat_core.push_back(lemma); m_unsat_core.push_back(lemma);

33
src/muz/spacer/spacer_unsat_core_learner.h
View file

@ -22,6 +22,7 @@ Revision History:
#include "ast/ast.h" #include "ast/ast.h"
#include "muz/spacer/spacer_util.h" #include "muz/spacer/spacer_util.h"
#include "muz/spacer/spacer_proof_utils.h" #include "muz/spacer/spacer_proof_utils.h"
#include "muz/spacer/spacer_iuc_proof.h"
namespace spacer { namespace spacer {
@ -31,13 +32,32 @@ namespace spacer {
class unsat_core_learner { class unsat_core_learner {
typedef obj_hashtable<expr> expr_set; typedef obj_hashtable<expr> expr_set;
ast_manager& m;
iuc_proof& m_pr;
ptr_vector<unsat_core_plugin> m_plugins;
ast_mark m_closed;
expr_ref_vector m_unsat_core;
public: public:
unsat_core_learner(ast_manager& m, iuc_proof& pr) : unsat_core_learner(ast_manager& m, iuc_proof& pr) :
m(m), m_pr(pr), m_unsat_core(m) {}; m(m), m_pr(pr), m_unsat_core(m) {};
virtual ~unsat_core_learner(); virtual ~unsat_core_learner();
ast_manager& m; ast_manager& get_manager() {return m;}
iuc_proof& m_pr;
bool is_a(proof *pr) {
// AG: treat hypotheses as A
// AG: assume that all B-hyp have been eliminated
// AG: this is not yet true in case of arithmetic eq_prop
return m_pr.is_a_marked(pr) || is_h(pr);
}
bool is_b(proof *pr) {return m_pr.is_b_marked(pr);}
bool is_h(proof *pr) {return m_pr.is_h_marked(pr);}
bool is_b_pure(proof *pr) { return m_pr.is_b_pure(pr);}
bool is_b_open(proof *p) {return m_pr.is_b_marked(p) && !is_closed (p);}
/* /*
* register a plugin for computation of partial unsat cores * register a plugin for computation of partial unsat cores
@ -59,7 +79,6 @@ namespace spacer {
bool is_closed(proof* p); bool is_closed(proof* p);
void set_closed(proof* p, bool value); void set_closed(proof* p, bool value);
bool is_b_open (proof *p);
/* /*
* adds a lemma to the unsat core * adds a lemma to the unsat core
@ -67,14 +86,6 @@ namespace spacer {
void add_lemma_to_core(expr* lemma); void add_lemma_to_core(expr* lemma);
private: private:
ptr_vector<unsat_core_plugin> m_plugins;
ast_mark m_closed;
/*
* collects the lemmas of the unsat-core
* will at the end be inserted into unsat_core.
*/
expr_ref_vector m_unsat_core;
/* /*
* computes partial core for step by delegating computation to plugins * computes partial core for step by delegating computation to plugins

162
src/muz/spacer/spacer_unsat_core_plugin.cpp
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@ -34,27 +34,25 @@ Revision History:
namespace spacer { namespace spacer {
unsat_core_plugin::unsat_core_plugin(unsat_core_learner& learner): unsat_core_plugin::unsat_core_plugin(unsat_core_learner& ctx):
m(learner.m), m_learner(learner) {}; m(ctx.get_manager()), m_ctx(ctx) {};
void unsat_core_plugin_lemma::compute_partial_core(proof* step) { void unsat_core_plugin_lemma::compute_partial_core(proof* step) {
SASSERT(m_learner.m_pr.is_a_marked(step)); SASSERT(m_ctx.is_a(step));
SASSERT(m_learner.m_pr.is_b_marked(step)); SASSERT(m_ctx.is_b(step));
for (proof* premise : m.get_parents(step)) { for (auto* p : m.get_parents(step)) {
if (m_ctx.is_b_open (p)) {
if (m_learner.is_b_open (premise)) {
// by IH, premises that are AB marked are already closed // by IH, premises that are AB marked are already closed
SASSERT(!m_learner.m_pr.is_a_marked(premise)); SASSERT(!m_ctx.is_a(p));
add_lowest_split_to_core(premise); add_lowest_split_to_core(p);
} }
} }
m_learner.set_closed(step, true); m_ctx.set_closed(step, true);
} }
void unsat_core_plugin_lemma::add_lowest_split_to_core(proof* step) const void unsat_core_plugin_lemma::add_lowest_split_to_core(proof* step) const {
{ SASSERT(m_ctx.is_b_open(step));
SASSERT(m_learner.is_b_open(step));
ptr_buffer<proof> todo; ptr_buffer<proof> todo;
todo.push_back(step); todo.push_back(step);
@ -64,45 +62,46 @@ namespace spacer {
todo.pop_back(); todo.pop_back();
// if current step hasn't been processed, // if current step hasn't been processed,
if (!m_learner.is_closed(pf)) { if (!m_ctx.is_closed(pf)) {
m_learner.set_closed(pf, true); m_ctx.set_closed(pf, true);
// the step is b-marked and not closed. // the step is b-marked and not closed.
// by I.H. the step must be already visited // by I.H. the step must be already visited
// so if it is also a-marked, it must be closed // so if it is also a-marked, it must be closed
SASSERT(m_learner.m_pr.is_b_marked(pf)); SASSERT(m_ctx.is_b(pf));
SASSERT(!m_learner.m_pr.is_a_marked(pf)); SASSERT(!m_ctx.is_a(pf));
// the current step needs to be interpolated: // the current step needs to be interpolated:
expr* fact = m.get_fact(pf); expr* fact = m.get_fact(pf);
// if we trust the current step and we are able to use it // if we trust the current step and we are able to use it
if (m_learner.m_pr.is_b_pure (pf) && if (m_ctx.is_b_pure (pf) && (m.is_asserted(pf) || is_literal(m, fact))) {
(m.is_asserted(pf) || is_literal(m, fact))) {
// just add it to the core // just add it to the core
m_learner.add_lemma_to_core(fact); m_ctx.add_lemma_to_core(fact);
} }
// otherwise recurse on premises // otherwise recurse on premises
else { else {
for (proof* premise : m.get_parents(pf)) for (proof* premise : m.get_parents(pf))
if (m_learner.is_b_open(premise)) if (m_ctx.is_b_open(premise))
todo.push_back(premise); todo.push_back(premise);
} }
} }
} }
} }
void unsat_core_plugin_farkas_lemma::compute_partial_core(proof* step) /***
{ * FARKAS
SASSERT(m_learner.m_pr.is_a_marked(step)); */
SASSERT(m_learner.m_pr.is_b_marked(step)); void unsat_core_plugin_farkas_lemma::compute_partial_core(proof* step) {
SASSERT(m_ctx.is_a(step));
SASSERT(m_ctx.is_b(step));
// XXX this assertion should be true so there is no need to check for it // XXX this assertion should be true so there is no need to check for it
SASSERT (!m_learner.is_closed (step)); SASSERT (!m_ctx.is_closed (step));
func_decl* d = step->get_decl(); func_decl* d = step->get_decl();
symbol sym; symbol sym;
if (!m_learner.is_closed(step) && // if step is not already interpolated TRACE("spacer.farkas",
is_farkas_lemma(m, step)) { tout << "looking at: " << mk_pp(step, m) << "\n";);
// weaker check: d->get_num_parameters() >= m.get_num_parents(step) + 2 if (!m_ctx.is_closed(step) && is_farkas_lemma(m, step)) {
// weaker check : d->get_num_parameters() >= m.get_num_parents(step) + 2
SASSERT(d->get_num_parameters() == m.get_num_parents(step) + 2); SASSERT(d->get_num_parameters() == m.get_num_parents(step) + 2);
SASSERT(m.has_fact(step)); SASSERT(m.has_fact(step));
@ -135,32 +134,33 @@ namespace spacer {
*/ */
parameter const* params = d->get_parameters() + 2; // point to the first Farkas coefficient parameter const* params = d->get_parameters() + 2; // point to the first Farkas coefficient
STRACE("spacer.farkas", TRACE("spacer.farkas",
verbose_stream() << "Farkas input: "<< "\n"; tout << "Farkas input: "<< "\n";
for (unsigned i = 0; i < m.get_num_parents(step); ++i) { for (unsigned i = 0; i < m.get_num_parents(step); ++i) {
proof * prem = m.get_parent(step, i); proof * prem = m.get_parent(step, i);
rational coef = params[i].get_rational(); rational coef = params[i].get_rational();
bool b_pure = m_learner.m_pr.is_b_pure (prem); bool b_pure = m_ctx.is_b_pure (prem);
verbose_stream() << (b_pure?"B":"A") << " " << coef << " " << mk_pp(m.get_fact(prem), m) << "\n"; tout << (b_pure?"B":"A") << " " << coef << " " << mk_pp(m.get_fact(prem), m) << "\n";
} }
); );
bool can_be_closed = true; bool done = true;
for (unsigned i = 0; i < m.get_num_parents(step); ++i) { for (unsigned i = 0; i < m.get_num_parents(step); ++i) {
proof * premise = m.get_parent(step, i); proof * premise = m.get_parent(step, i);
if (m_learner.is_b_open (premise)) { if (m_ctx.is_b_open (premise)) {
SASSERT(!m_learner.m_pr.is_a_marked(premise)); SASSERT(!m_ctx.is_a(premise));
if (m_learner.m_pr.is_b_pure (step)) { if (m_ctx.is_b_pure (premise)) {
if (!m_use_constant_from_a) { if (!m_use_constant_from_a) {
rational coefficient = params[i].get_rational(); rational coefficient = params[i].get_rational();
coeff_lits.push_back(std::make_pair(abs(coefficient), (app*)m.get_fact(premise))); coeff_lits.push_back(std::make_pair(abs(coefficient), (app*)m.get_fact(premise)));
} }
} }
else { else {
can_be_closed = false; // -- mixed premise, won't be able to close this proof step
done = false;
if (m_use_constant_from_a) { if (m_use_constant_from_a) {
rational coefficient = params[i].get_rational(); rational coefficient = params[i].get_rational();
@ -176,6 +176,7 @@ namespace spacer {
} }
} }
// TBD: factor into another method
if (m_use_constant_from_a) { if (m_use_constant_from_a) {
params += m.get_num_parents(step); // point to the first Farkas coefficient, which corresponds to a formula in the conclusion params += m.get_num_parents(step); // point to the first Farkas coefficient, which corresponds to a formula in the conclusion
@ -205,13 +206,12 @@ namespace spacer {
} }
// only if all b-premises can be used directly, add the farkas core and close the step // only if all b-premises can be used directly, add the farkas core and close the step
if (can_be_closed) { // AG: this decision needs to be re-evaluated. If the proof cannot be closed, literals above
m_learner.set_closed(step, true); // AG: it will go into the core. However, it does not mean that this literal should/could not be added.
m_ctx.set_closed(step, done);
expr_ref res = compute_linear_combination(coeff_lits); expr_ref res = compute_linear_combination(coeff_lits);
TRACE("spacer.farkas", tout << "Farkas core: " << res << "\n";);
m_learner.add_lemma_to_core(res); m_ctx.add_lemma_to_core(res);
}
} }
} }
@ -235,12 +235,12 @@ namespace spacer {
void unsat_core_plugin_farkas_lemma_optimized::compute_partial_core(proof* step) void unsat_core_plugin_farkas_lemma_optimized::compute_partial_core(proof* step)
{ {
SASSERT(m_learner.m_pr.is_a_marked(step)); SASSERT(m_ctx.is_a(step));
SASSERT(m_learner.m_pr.is_b_marked(step)); SASSERT(m_ctx.is_b(step));
func_decl* d = step->get_decl(); func_decl* d = step->get_decl();
symbol sym; symbol sym;
if (!m_learner.is_closed(step) && // if step is not already interpolated if (!m_ctx.is_closed(step) && // if step is not already interpolated
is_farkas_lemma(m, step)) { is_farkas_lemma(m, step)) {
SASSERT(d->get_num_parameters() == m.get_num_parents(step) + 2); SASSERT(d->get_num_parameters() == m.get_num_parents(step) + 2);
SASSERT(m.has_fact(step)); SASSERT(m.has_fact(step));
@ -249,25 +249,25 @@ namespace spacer {
parameter const* params = d->get_parameters() + 2; // point to the first Farkas coefficient parameter const* params = d->get_parameters() + 2; // point to the first Farkas coefficient
STRACE("spacer.farkas", TRACE("spacer.farkas",
verbose_stream() << "Farkas input: "<< "\n"; tout << "Farkas input: "<< "\n";
for (unsigned i = 0; i < m.get_num_parents(step); ++i) { for (unsigned i = 0; i < m.get_num_parents(step); ++i) {
proof * prem = m.get_parent(step, i); proof * prem = m.get_parent(step, i);
rational coef = params[i].get_rational(); rational coef = params[i].get_rational();
bool b_pure = m_learner.m_pr.is_b_pure (prem); bool b_pure = m_ctx.is_b_pure (prem);
verbose_stream() << (b_pure?"B":"A") << " " << coef << " " << mk_pp(m.get_fact(prem), m_learner.m) << "\n"; tout << (b_pure?"B":"A") << " " << coef << " " << mk_pp(m.get_fact(prem), m) << "\n";
} }
); );
bool can_be_closed = true; bool can_be_closed = true;
for (unsigned i = 0; i < m.get_num_parents(step); ++i) { for (unsigned i = 0; i < m.get_num_parents(step); ++i) {
proof * premise = m.get_parent(step, i); proof * premise = m.get_parent(step, i);
if (m_learner.m_pr.is_b_marked(premise) && !m_learner.is_closed(premise)) if (m_ctx.is_b(premise) && !m_ctx.is_closed(premise))
{ {
SASSERT(!m_learner.m_pr.is_a_marked(premise)); SASSERT(!m_ctx.is_a(premise));
if (m_learner.m_pr.is_b_pure(premise)) if (m_ctx.is_b_pure(premise))
{ {
rational coefficient = params[i].get_rational(); rational coefficient = params[i].get_rational();
linear_combination.push_back linear_combination.push_back
@ -283,7 +283,7 @@ namespace spacer {
// only if all b-premises can be used directly, close the step and add linear combinations for later processing // only if all b-premises can be used directly, close the step and add linear combinations for later processing
if (can_be_closed) if (can_be_closed)
{ {
m_learner.set_closed(step, true); m_ctx.set_closed(step, true);
if (!linear_combination.empty()) if (!linear_combination.empty())
{ {
m_linear_combinations.push_back(linear_combination); m_linear_combinations.push_back(linear_combination);
@ -349,7 +349,7 @@ namespace spacer {
SASSERT(!coeff_lits.empty()); SASSERT(!coeff_lits.empty());
expr_ref linear_combination = compute_linear_combination(coeff_lits); expr_ref linear_combination = compute_linear_combination(coeff_lits);
m_learner.add_lemma_to_core(linear_combination); m_ctx.add_lemma_to_core(linear_combination);
} }
} }
@ -480,7 +480,7 @@ namespace spacer {
SASSERT(!coeff_lits.empty()); // since then previous outer loop would have found solution already SASSERT(!coeff_lits.empty()); // since then previous outer loop would have found solution already
expr_ref linear_combination = compute_linear_combination(coeff_lits); expr_ref linear_combination = compute_linear_combination(coeff_lits);
m_learner.add_lemma_to_core(linear_combination); m_ctx.add_lemma_to_core(linear_combination);
} }
return; return;
} }
@ -504,10 +504,10 @@ namespace spacer {
{ {
ptr_vector<proof> todo; ptr_vector<proof> todo;
SASSERT(m_learner.m_pr.is_a_marked(step)); SASSERT(m_ctx.is_a(step));
SASSERT(m_learner.m_pr.is_b_marked(step)); SASSERT(m_ctx.is_b(step));
SASSERT(m.get_num_parents(step) > 0); SASSERT(m.get_num_parents(step) > 0);
SASSERT(!m_learner.is_closed(step)); SASSERT(!m_ctx.is_closed(step));
todo.push_back(step); todo.push_back(step);
while (!todo.empty()) while (!todo.empty())
@ -516,7 +516,7 @@ namespace spacer {
todo.pop_back(); todo.pop_back();
// if we need to deal with the node and if we haven't added the corresponding edges so far // if we need to deal with the node and if we haven't added the corresponding edges so far
if (!m_learner.is_closed(current) && !m_visited.is_marked(current)) if (!m_ctx.is_closed(current) && !m_visited.is_marked(current))
{ {
// compute smallest subproof rooted in current, which has only good edges // compute smallest subproof rooted in current, which has only good edges
// add an edge from current to each leaf of that subproof // add an edge from current to each leaf of that subproof
@ -527,7 +527,7 @@ namespace spacer {
} }
} }
m_learner.set_closed(step, true); m_ctx.set_closed(step, true);
} }
@ -538,7 +538,7 @@ namespace spacer {
ptr_buffer<proof> todo_subproof; ptr_buffer<proof> todo_subproof;
for (proof* premise : m.get_parents(step)) { for (proof* premise : m.get_parents(step)) {
if (m_learner.m_pr.is_b_marked(premise)) { if (m_ctx.is_b(premise)) {
todo_subproof.push_back(premise); todo_subproof.push_back(premise);
} }
} }
@ -548,21 +548,21 @@ namespace spacer {
todo_subproof.pop_back(); todo_subproof.pop_back();
// if we need to deal with the node // if we need to deal with the node
if (!m_learner.is_closed(current)) if (!m_ctx.is_closed(current))
{ {
SASSERT(!m_learner.m_pr.is_a_marked(current)); // by I.H. the step must be already visited SASSERT(!m_ctx.is_a(current)); // by I.H. the step must be already visited
// and the current step needs to be interpolated: // and the current step needs to be interpolated:
if (m_learner.m_pr.is_b_marked(current)) if (m_ctx.is_b(current))
{ {
// if we trust the current step and we are able to use it // if we trust the current step and we are able to use it
if (m_learner.m_pr.is_b_pure (current) && if (m_ctx.is_b_pure (current) &&
(m.is_asserted(current) || (m.is_asserted(current) ||
is_literal(m, m.get_fact(current)))) is_literal(m, m.get_fact(current))))
{ {
// we found a leaf of the subproof, so // we found a leaf of the subproof, so
// 1) we add corresponding edges // 1) we add corresponding edges
if (m_learner.m_pr.is_a_marked(step)) if (m_ctx.is_a(step))
{ {
add_edge(nullptr, current); // current is sink add_edge(nullptr, current); // current is sink
} }
@ -684,7 +684,7 @@ namespace spacer {
m_min_cut.compute_min_cut(cut_nodes); m_min_cut.compute_min_cut(cut_nodes);
for (unsigned cut_node : cut_nodes) { for (unsigned cut_node : cut_nodes) {
m_learner.add_lemma_to_core(m_node_to_formula[cut_node]); m_ctx.add_lemma_to_core(m_node_to_formula[cut_node]);
} }
} }
} }

2
src/muz/spacer/spacer_unsat_core_plugin.h
View file

@ -36,7 +36,7 @@ namespace spacer {
virtual void compute_partial_core(proof* step) = 0; virtual void compute_partial_core(proof* step) = 0;
virtual void finalize(){}; virtual void finalize(){};
unsat_core_learner& m_learner; unsat_core_learner& m_ctx;
}; };
class unsat_core_plugin_lemma : public unsat_core_plugin { class unsat_core_plugin_lemma : public unsat_core_plugin {