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working on pdr gen

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Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>
This commit is contained in:
Nikolaj Bjorner 2013-02-08 16:54:05 -08:00
parent 2e2fa84d40
commit 3ad43c60a9
3 changed files with 93 additions and 41 deletions
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95
src/muz_qe/pdr_generalizers.cpp
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@ -147,8 +147,12 @@ namespace pdr {
}
// -----------------------------
// ---------------------------------
// core_arith_inductive_generalizer
// NB. this is trying out some ideas for generalization in
// an ad hoc specialized way. arith_inductive_generalizer should
// not be used by default. It is a place-holder for a general purpose
// extrapolator of a lattice basis.
core_arith_inductive_generalizer::core_arith_inductive_generalizer(context& ctx):
core_generalizer(ctx),
@ -168,42 +172,50 @@ namespace pdr {
svector<eq> eqs;
get_eqs(core, eqs);
if (eqs.empty()) {
return;
}
expr_ref_vector new_core(m);
new_core.append(core);
for (unsigned eq = 0; eq < eqs.size(); ++eq) {
rational r = eqs[eq].m_value;
expr* x = eqs[eq].m_term;
unsigned k = eqs[eq].m_i;
unsigned l = eqs[eq].m_j;
expr_ref_vector new_core(m);
for (unsigned i = 0; i < core.size(); ++i) {
if (i == k || k == l) {
new_core.push_back(m.mk_true());
}
else {
if (!substitute_alias(r, x, core[i].get(), e)) {
e = core[i].get();
}
new_core.push_back(e);
new_core[l] = m.mk_true();
new_core[k] = m.mk_true();
for (unsigned i = 0; i < new_core.size(); ++i) {
if (substitute_alias(r, x, new_core[i].get(), e)) {
new_core[i] = e;
}
}
if (abs(r) >= rational(2) && a.is_int(x)) {
new_core[k] = m.mk_eq(a.mk_mod(x, a.mk_numeral(abs(r), true)), a.mk_numeral(rational(0), true));
new_core[l] = a.mk_ge(x, a.mk_numeral(r, true));
new_core[k] = m.mk_eq(a.mk_mod(x, a.mk_numeral(rational(2), true)), a.mk_numeral(rational(0), true));
new_core[l] = a.mk_le(x, a.mk_numeral(rational(0), true));
}
}
bool inductive = n.pt().check_inductive(n.level(), new_core, uses_level);
bool inductive = n.pt().check_inductive(n.level(), new_core, uses_level);
IF_VERBOSE(1,
verbose_stream() << (inductive?"":"non") << "inductive\n";
for (unsigned j = 0; j < new_core.size(); ++j) {
verbose_stream() << mk_pp(new_core[j].get(), m) << "\n";
});
if (inductive) {
core.reset();
core.append(new_core);
}
IF_VERBOSE(1,
verbose_stream() << (inductive?"":"non") << "inductive\n";
verbose_stream() << "old\n";
for (unsigned j = 0; j < core.size(); ++j) {
verbose_stream() << mk_pp(core[j].get(), m) << "\n";
}
verbose_stream() << "new\n";
for (unsigned j = 0; j < new_core.size(); ++j) {
verbose_stream() << mk_pp(new_core[j].get(), m) << "\n";
});
if (inductive) {
core.reset();
core.append(new_core);
}
}
@ -289,13 +301,34 @@ namespace pdr {
result = m.mk_not(result);
return true;
}
if (a.is_le(e, y, z) && a.is_numeral(z, r2) && r == r2) {
result = a.mk_le(y, x);
return true;
if (a.is_le(e, y, z) && a.is_numeral(z, r2)) {
if (r == r2) {
result = a.mk_le(y, x);
return true;
}
if (r == r2 + rational(1)) {
result = a.mk_lt(y, x);
return true;
}
if (r == r2 - rational(1)) {
result = a.mk_le(y, a.mk_sub(x, a.mk_numeral(rational(1), a.is_int(x))));
return true;
}
}
if (a.is_ge(e, y, z) && a.is_numeral(z, r2) && r == r2) {
result = a.mk_ge(y, x);
return true;
if (a.is_ge(e, y, z) && a.is_numeral(z, r2)) {
if (r == r2) {
result = a.mk_ge(y, x);
return true;
}
if (r2 == r + rational(1)) {
result = a.mk_gt(y, x);
return true;
}
if (r2 == r - rational(1)) {
result = a.mk_ge(y, a.mk_sub(x, a.mk_numeral(rational(1), a.is_int(x))));
return true;
}
}
return false;
}