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propagate intervals from containing slice

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This commit is contained in:
Jakob Rath 2024-01-29 16:45:14 +01:00
parent f0b056d859
commit 75527e8e19
2 changed files with 104 additions and 3 deletions
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105
src/sat/smt/polysat/viable.cpp
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@ -556,7 +556,7 @@ namespace polysat {
auto after = last;
if (c.inconsistent())
verbose_stream() << "inconistent explain\n";
verbose_stream() << "inconsistent explain\n";
TRACE("bv", display_explain(tout));
auto unmark = [&]() {
@ -583,7 +583,7 @@ namespace polysat {
result.append(e->deps);
if (!index.is_null())
result.push_back(c.get_dependency(index));
};
};
if (last.e->interval.is_full()) {
explain_entry(last.e);
@ -619,13 +619,112 @@ namespace polysat {
// there is just one entry
SASSERT(m_explain.size() == 1);
explain_entry(last.e);
propagate_from_containing_slice(last.e, last.value, result);
}
unmark();
if (c.inconsistent())
verbose_stream() << "inconistent after explain\n";
verbose_stream() << "inconsistent after explain\n";
return result;
}
void viable::propagate_from_containing_slice(entry* e, rational const& value, dependency_vector const& e_deps) {
for (auto const& slice : m_overlaps)
propagate_from_containing_slice(e, value, e_deps, slice);
}
void viable::propagate_from_containing_slice(entry* e, rational const& value, dependency_vector const& e_deps, offset_slice const& slice) {
auto [w, offset] = slice;
if (w == m_var)
return;
unsigned const v_sz = c.size(m_var);
unsigned const w_sz = c.size(w);
verbose_stream() << "v" << m_var << " size " << v_sz << ", v" << w << " size " << w_sz << " offset " << offset << "\n";
rational const& lo = e->interval.lo_val();
rational const& hi = e->interval.hi_val();
if (v_sz == w_sz) {
return;
#if 0
// TODO: copy interval over?
rational const& w_lo = lo;
rational const& w_hi = hi;
verbose_stream() << "=> v" << w << " not in [" << w_lo << ";" << w_hi << "[\n";
auto sc = ~cs.ult(c.var(w) - w_lo, w_hi - w_lo);
dependency_vector deps;
deps.append(result); // explains e
deps.push_back(offset_claim{m_var, slice}); // v = w
auto exp = c.propagate(sc, deps);
if (c.inconsistent()) {
verbose_stream() << "YYY inconsistent " << sc << " " << exp << "\n";
}
#endif
return;
}
if (offset == 0) {
verbose_stream() << "propagate interval " << e->interval << " from v" << m_var << " to v" << w << "\n";
if (e->interval.current_len() > rational::power_of_two(v_sz) - rational::power_of_two(w_sz)) {
verbose_stream() << "generic interval works\n";
rational w_lo = mod2k(lo, w_sz);
rational w_hi = mod2k(hi, w_sz);
verbose_stream() << "=> v" << w << " not in [" << w_lo << ";" << w_hi << "[\n";
SASSERT(w_lo != w_hi); // otherwise the length of e->interval would have been smaller
auto sc = ~cs.ult(c.var(w) - w_lo, w_hi - w_lo);
dependency_vector deps;
deps.append(e_deps); // explains e
deps.push_back(offset_claim{m_var, slice}); // v[w_sz:0] = w
auto exp = c.propagate(sc, deps);
if (c.inconsistent()) {
verbose_stream() << "XXX1 inconsistent " << sc << " " << exp << "\n";
}
}
#if 0
// if other part is constant
// v[v_sz-1:w_sz] == n, v[w_sz-1:0] == w
if (rational n; m_fixed_bits.try_get_value(v_sz - 1, w_sz, n)) {
rational lo_d = machine_div2k(lo, w_sz);
rational hi_d = machine_div2k(hi, w_sz);
rational w_lo = (lo_d == n) ? mod2k(lo, w_sz) : rational(0);
rational w_hi = (hi_d == n) ? mod2k(hi, w_sz) : rational(0);
if (w_lo != w_hi) {
verbose_stream() << "=> v" << w << " not in [" << w_lo << ";" << w_hi << "[\n";
}
else if (ivl.currently_contains(n * rational::power_of_two(w_sz))) {
verbose_stream() << "=> no value for v" << w << "\n";
}
}
#endif
// we have the assignment for v, thus a fixed value for the upper slice
// v[v_sz-1:w_sz] == n, v[w_sz-1:0] == w
rational n = machine_div2k(value, w_sz);
rational lo_d = machine_div2k(lo, w_sz);
rational hi_d = machine_div2k(hi, w_sz);
rational w_lo = (lo_d == n) ? mod2k(lo, w_sz) : rational(0);
rational w_hi = (hi_d == n) ? mod2k(hi, w_sz) : rational(0);
verbose_stream() << "n " << n << " lo_d " << lo_d << " hi_d " << hi_d << " w_lo " << w_lo << " w_hi " << w_hi << "\n";
if (w_lo != w_hi) {
verbose_stream() << "=> v" << w << " not in [" << w_lo << ";" << w_hi << "[\n";
auto sc = ~cs.ult(c.var(w) - w_lo, w_hi - w_lo);
dependency_vector deps;
deps.append(e_deps); // explains e
deps.push_back(offset_claim{m_var, slice}); // v[w_sz:0] = w
deps.push_back(fixed_claim{m_var, n, w_sz, v_sz - w_sz}); // v[v_sz-1:w_sz] = n
auto exp = c.propagate(sc, deps);
if (c.inconsistent()) {
verbose_stream() << "XXX2 inconsistent " << sc << " " << exp << "\n";
}
}
else if (e->interval.currently_contains(n * rational::power_of_two(w_sz))) {
verbose_stream() << "=> no value for v" << w << "\n";
}
}
else {
// TODO
}
}
/*
* For two consecutive intervals
*

2
src/sat/smt/polysat/viable.h
View file

@ -115,6 +115,8 @@ namespace polysat {
bool intersect(pvar v, entry* e);
void propagate_from_containing_slice(entry* e, rational const& value, dependency_vector const& e_deps);
void propagate_from_containing_slice(entry* e, rational const& value, dependency_vector const& e_deps, offset_slice const& slice);
// find the first non-fixed entry that overlaps with val, if any.
entry* find_overlap(rational& val);