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Simplify code

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This commit is contained in:
CEisenhofer 2026-04-13 14:06:06 +02:00
parent 276b9c38af
commit d620f20c63
4 changed files with 29 additions and 95 deletions
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30
src/smt/theory_nseq.cpp
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@ -613,7 +613,9 @@ namespace smt {
if (!m_nielsen_literals.empty() && m_nielsen.sat_node() != nullptr &&
all_of(m_nielsen_literals, [&](auto lit) { return l_true == ctx.get_assignment(lit); })) {
IF_VERBOSE(1, verbose_stream() << "nseq final_check: satifiable state revisited\n");
return FC_DONE;
// Re-run solving/model extraction instead of early exiting on a
// cached SAT node. This avoids stale sat paths after additional
// SAT assignments were introduced in prior FC_CONTINUE rounds.
}
// unfold higher-order terms when sequence structure is known
@ -693,8 +695,13 @@ namespace smt {
// Nielsen found a consistent assignment for positive constraints.
SASSERT(has_eq_or_mem); // we should have axiomatized them
if (!add_nielsen_assumptions())
return FC_CONTINUE;
if (!add_nielsen_assumptions()) {
// If assumptions remain undefined, returning SAT can yield
// unsound/invalid models because the chosen Nielsen branch
// is not yet committed in the outer SAT core.
IF_VERBOSE(1, verbose_stream() << "nseq final_check: unresolved assumptions, FC_GIVEUP\n";);
return FC_GIVEUP;
}
if (!check_length_coherence())
return FC_CONTINUE;
@ -730,17 +737,22 @@ namespace smt {
//std::cout << "Nielsen assumptions:\n";
ctx.push_trail(reset_vector(m_nielsen_literals));
for (auto const& c : m_nielsen.sat_node()->constraints()) {
bool was_internalized = ctx.e_internalized(c.fml);
auto lit = mk_literal(c.fml);
m_nielsen_literals.push_back(lit);
std::cout << "Assumption: " << mk_pp(c.fml, m) << std::endl;
// Ensure Nielsen assumptions participate in SAT search instead of
// remaining permanently undefined under pure phase hints.
ctx.mark_as_relevant(lit);
// std::cout << "Assumption: " << mk_pp(c.fml, m) << std::endl;
switch (ctx.get_assignment(lit)) {
case l_true:
break;
case l_undef:
//std::cout << "Undef [" << lit << "]: " << mk_pp(c.fml, m) << "\n";
std::cout << "Undef [" << lit << "]: " << mk_pp(c.fml, m) << std::endl;
has_undef = true;
ctx.force_phase(lit);
// Commit the chosen Nielsen assumption to the SAT core so it
// cannot remain permanently undefined in a partial model.
ctx.mk_th_axiom(get_id(), 1, &lit);
ctx.force_phase(lit);
IF_VERBOSE(2, verbose_stream() <<
"nseq final_check: adding nielsen assumption " << c.fml << "\n";);
TRACE(seq, tout << "assign: " << c.fml << "\n");
@ -749,10 +761,10 @@ namespace smt {
// this should not happen because nielsen checks for this before returning a satisfying path.
IF_VERBOSE(1, verbose_stream()
<< "nseq final_check: nielsen assumption " << c.fml << " is false\n";);
ctx.force_phase(lit);
has_undef = true;
ctx.mk_th_axiom(get_id(), 1, &lit);
ctx.force_phase(lit);
//std::cout << "False [" << lit << "]: " << mk_pp(c.fml, m) << std::endl;
std::cout << "False [" << lit << "]: " << mk_pp(c.fml, m) << std::endl;
break;
}
}