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testing inference based on complementary bounds

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Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>
This commit is contained in:
Nikolaj Bjorner 2023-01-02 17:30:08 -08:00
parent 56bda59de9
commit 824c10711c
3 changed files with 88 additions and 88 deletions
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115
src/math/polysat/viable.cpp
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@ -726,73 +726,70 @@ namespace polysat {
return !out_c.empty();
}
bool viable::has_max_forbidden(pvar v, rational& out_lo, rational& out_hi, vector<signed_constraint>& out_c) {
bool viable::has_max_forbidden(pvar v, signed_constraint const& c, rational& out_lo, rational& out_hi, vector<signed_constraint>& out_c) {
out_c.reset();
entry const* first = m_units[v];
entry const* e = first;
bool found = false;
if (!e)
return false;
auto covers_all = [&](rational const& lo1, rational const& hi1, rational const lo2, rational const& hi2) {
SASSERT(lo1 != hi1);
if (lo1 < hi1) {
return lo2 <= hi1 && lo1 <= hi2;
}
else
// hi1 < lo1
return hi1 <= hi2 && hi2 <= lo2 && lo2 <= lo1;
};
auto overlap_left = [&](rational const& lo1, rational const& hi1, rational const lo2, rational const& hi2) {
if (lo2 < hi2)
return lo2 <= hi1 && hi1 <= hi2;
else
// hi2 < lo2
return lo1 < lo2 && (hi1 <= hi2 || lo2 <= hi1);
};
do {
found = false;
do {
if (e->refined)
goto next;
auto const& lo = e->interval.lo();
auto const& hi = e->interval.hi();
if (!lo.is_val() || !hi.is_val())
goto next;
if (out_c.contains(e->src))
goto next;
if (out_c.empty()) {
out_c.push_back(e->src);
out_lo = lo.val();
out_hi = hi.val();
found = true;
}
else if (covers_all(out_lo, out_hi, lo.val(), hi.val()))
return false;
// [lo, hi0, hi[
// [lo, hi0, 0, hi[
else if (overlap_left(lo.val(), hi.val(), out_lo, out_hi)) {
out_c.push_back(e->src);
out_lo = lo.val();
found = true;
}
// [lo, lo0, hi[
// [lo, 0, lo0, hi[
else if (overlap_left(out_lo, out_hi, lo.val(), hi.val())) {
out_c.push_back(e->src);
out_hi = hi.val();
found = true;
}
next:
e = e->next();
}
while (e != first);
if (e->src == c)
break;
e = e->next();
}
while (found);
return !out_c.empty();
while (e != first);
if (e->src != c)
return false;
entry const* e0 = e;
do {
entry const* n = e->next();
while (n != first) {
entry const* n1 = n->next();
if (n1 == e)
break;
if (!e->interval.currently_contains(n1->interval.lo_val()))
if (e->interval.hi_val() != n1->interval.lo_val())
break;
n = n1;
}
if (e == e0) {
out_hi = n->interval.lo_val();
if (!n->interval.lo().is_val())
out_c.push_back(s.eq(n->interval.lo(), out_hi));
}
else if (n == e0) {
out_lo = e->interval.hi_val();
if (!e->interval.hi().is_val())
out_c.push_back(s.eq(e->interval.hi(), out_lo));
}
else if (!e->interval.is_full()) {
auto const& hi = e->interval.hi();
auto const& next_lo = n->interval.lo();
auto const& next_hi = n->interval.hi();
auto lhs = hi - next_lo;
auto rhs = next_hi - next_lo;
signed_constraint c = s.m_constraints.ult(lhs, rhs);
out_c.push_back(c);
}
if (e != e0) {
for (auto sc : e->side_cond)
out_c.push_back(sc);
out_c.push_back(e->src);
}
e = n;
}
while (e != e0);
IF_VERBOSE(2,
verbose_stream() << "has-max-forbidden " << e->src << "\n";
verbose_stream() << "v" << v << " " << out_lo << " " << out_hi << " " << out_c << "\n";
display(verbose_stream(), v) << "\n");
return true;
}