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address divergence in the case of shared theory symbols. Codeplex issue 147, thanks to George Karpenkov

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Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>
This commit is contained in:
Nikolaj Bjorner 2014-12-09 16:04:25 +01:00
commit 08cb8b8de8
74 changed files with 1280 additions and 896 deletions
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32
src/smt/theory_arith_aux.h
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@ -928,11 +928,10 @@ namespace smt {
*/
template<typename Ext>
bool theory_arith<Ext>::is_safe_to_leave(theory_var x, bool& has_int) {
bool theory_arith<Ext>::is_safe_to_leave(theory_var x, bool& has_int, bool& shared) {
if (get_context().is_shared(get_enode(x))) {
return false;
}
context& ctx = get_context();
shared |= ctx.is_shared(get_enode(x));
column & c = m_columns[x];
typename svector<col_entry>::iterator it = c.begin_entries();
typename svector<col_entry>::iterator end = c.end_entries();
@ -944,8 +943,9 @@ namespace smt {
numeral const & coeff = r[it->m_row_idx].m_coeff;
if (s != null_theory_var && is_int(s)) has_int = true;
bool is_unsafe = (s != null_theory_var && is_int(s) && !coeff.is_int());
is_unsafe = is_unsafe || (s != null_theory_var && get_context().is_shared(get_enode(s)));
TRACE("opt", tout << "is v" << x << " safe to leave for v" << s << "? " << (is_unsafe?"no":"yes") << " " << (has_int?"int":"real") << "\n";
shared |= (s != null_theory_var && ctx.is_shared(get_enode(s)));
TRACE("opt", tout << "is v" << x << " safe to leave for v" << s
<< "? " << (is_unsafe?"no":"yes") << " " << (has_int?"int":"real") << "\n";
display_row(tout, r, true););
if (is_unsafe) return false;
}
@ -1072,10 +1072,12 @@ namespace smt {
}
template<typename Ext>
inf_eps_rational<inf_rational> theory_arith<Ext>::maximize(theory_var v, expr_ref& blocker) {
inf_eps_rational<inf_rational> theory_arith<Ext>::maximize(theory_var v, expr_ref& blocker, bool& has_shared) {
TRACE("bound_bug", display_var(tout, v); display(tout););
max_min_t r = max_min(v, true);
has_shared = false;
max_min_t r = max_min(v, true, has_shared);
if (r == UNBOUNDED) {
has_shared = false;
blocker = get_manager().mk_false();
return inf_eps_rational<inf_rational>::infinity();
}
@ -1299,10 +1301,11 @@ namespace smt {
Return true if succeeded.
*/
template<typename Ext>
typename theory_arith<Ext>::max_min_t theory_arith<Ext>::max_min(row & r, bool max) {
typename theory_arith<Ext>::max_min_t theory_arith<Ext>::max_min(row & r, bool max, bool& has_shared) {
TRACE("max_min", tout << "max_min...\n";);
m_stats.m_max_min++;
bool skipped_row = false;
has_shared = false;
SASSERT(valid_row_assignment());
SASSERT(satisfy_bounds());
@ -1332,7 +1335,7 @@ namespace smt {
bool has_int = false;
if ((curr_inc && at_upper(curr_x_j)) || (!curr_inc && at_lower(curr_x_j)))
continue; // variable cannot be used for max/min.
if (!is_safe_to_leave(curr_x_j, has_int)) {
if (!is_safe_to_leave(curr_x_j, has_int, has_shared)) {
skipped_row = true;
continue;
}
@ -1536,7 +1539,7 @@ namespace smt {
\brief Maximize/Minimize the given variable. The bounds of v are update if procedure succeeds.
*/
template<typename Ext>
typename theory_arith<Ext>::max_min_t theory_arith<Ext>::max_min(theory_var v, bool max) {
typename theory_arith<Ext>::max_min_t theory_arith<Ext>::max_min(theory_var v, bool max, bool& has_shared) {
expr* e = get_enode(v)->get_owner();
SASSERT(valid_row_assignment());
SASSERT(satisfy_bounds());
@ -1558,7 +1561,7 @@ namespace smt {
add_tmp_row_entry<true>(m_tmp_row, it->m_coeff, it->m_var);
}
}
max_min_t r = max_min(m_tmp_row, max);
max_min_t r = max_min(m_tmp_row, max, has_shared);
if (r == OPTIMIZED) {
TRACE("opt", tout << mk_pp(e, get_manager()) << " " << (max ? "max" : "min") << " value is: " << get_value(v) << "\n";
display_row(tout, m_tmp_row, true); display_row_info(tout, m_tmp_row););
@ -1581,12 +1584,13 @@ namespace smt {
template<typename Ext>
bool theory_arith<Ext>::max_min(svector<theory_var> const & vars) {
bool succ = false;
bool has_shared = false;
svector<theory_var>::const_iterator it = vars.begin();
svector<theory_var>::const_iterator end = vars.end();
for (; it != end; ++it) {
if (max_min(*it, true) == OPTIMIZED)
if (max_min(*it, true, has_shared) == OPTIMIZED && !has_shared)
succ = true;
if (max_min(*it, false) == OPTIMIZED)
if (max_min(*it, false, has_shared) == OPTIMIZED && !has_shared)
succ = true;
}
if (succ) {