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memory management in cross_nested is broken

This commit is contained in:
Lev Nachmanson 2019-07-20 16:58:00 -07:00
parent d5708b184a
commit 46f8159926
2 changed files with 84 additions and 38 deletions

View file

@ -51,10 +51,10 @@ public:
}
};
bool proceed_with_common_factor(nex* c, vector<nex*>& front, const std::unordered_map<lpvar, occ> & occurences) {
TRACE("nla_cn", tout << "c=" << *c << "\n";);
static bool extract_common_factor(nex* c, nex& f, const std::unordered_map<lpvar, occ> & occurences) {
SASSERT(c->is_sum());
auto f = nex::mul();
f.type() = expr_type::MUL;
SASSERT(f.children().empty());
unsigned size = c->children().size();
for(const auto & p : occurences) {
if (p.second.m_occs == size) {
@ -64,7 +64,16 @@ public:
}
}
}
if (f.children().size() == 0) return false;
return !f.children().empty();
}
bool proceed_with_common_factor(nex* c, vector<nex*>& front, const std::unordered_map<lpvar, occ> & occurences) {
TRACE("nla_cn", tout << "c=" << *c << "\n";);
SASSERT(c->is_sum());
nex f;
if (!extract_common_factor(c, f, occurences))
return false;
*c /= f;
f.simplify();
* c = nex::mul(f, *c);
@ -89,7 +98,8 @@ public:
TRACE("nla_cn", tout << "restore c=" << *c << ", m_e=" << m_e << "\n";);
for (unsigned i = 0; i < front.size(); i++)
*(front[i]) = copy_of_front[i];
TRACE("nla_cn", tout << "restore c=" << *c << ", m_e=" << m_e << "\n";);
TRACE("nla_cn", tout << "restore c=" << *c << "\n";);
TRACE("nla_cn", tout << "m_e=" << m_e << "\n";);
}
}
@ -113,11 +123,18 @@ public:
if(front.empty()) {
if (trivial_form)
return;
TRACE("nla_cn", tout << "got the cn form: m_e=" << m_e << "\n";);
SASSERT(!can_be_cross_nested_more(m_e));
auto e_to_report = m_e;
e_to_report.simplify();
m_call_on_result(e_to_report);
auto e_s = m_e;
e_s.simplify();
occurences = get_mult_occurences(e_s);
if (occurences.empty()) {
TRACE("nla_cn", tout << "got the cn form: e_s=" << e_s << "\n";);
SASSERT(!can_be_cross_nested_more(e_s));
m_call_on_result(e_s);
} else {
cross_nested cn(e_s, m_call_on_result);
cn.run();
}
} else {
nex* c = pop_back(front);
cross_nested_of_expr_on_front_elem(c, front, trivial_form);
@ -135,8 +152,12 @@ public:
split_with_var(*c, j, front);
TRACE("nla_cn", tout << "after split c=" << *c << "\nfront="; print_vector_of_ptrs(front, tout) << "\n";);
SASSERT(front.size());
nex* n = pop_back(front); TRACE("nla_cn", tout << "n=" << *n <<"\n";);
cross_nested_of_expr_on_front_elem(n, front, false); // we got a non-trivial_form
if (can_be_cross_nested_more(*c)) {
cross_nested_of_expr_on_front_elem(c, front, false);
} else {
nex* n = pop_back(front); TRACE("nla_cn", tout << "n=" << *n <<"\n";);
cross_nested_of_expr_on_front_elem(n, front, false); // we got a non-trivial_form
}
}
static void process_var_occurences(lpvar j, std::unordered_map<lpvar, occ>& occurences) {
auto it = occurences.find(j);
@ -190,7 +211,7 @@ public:
TRACE("nla_cn_details", tout << "e=" << e << "\noccs="; dump_occurences(tout, occurences) << "\n";);
return occurences;
}
bool can_be_cross_nested_more(const nex& s) const {
static bool can_be_cross_nested_more(const nex& s) {
auto e = s;
e.simplify();
TRACE("nla_cn_details", tout << "simplified " << e << "\n";);
@ -217,11 +238,8 @@ public:
return false;
}
}
void split_with_var(nex& e, lpvar j, vector<nex*> & front) {
TRACE("nla_cn_details", tout << "e = " << e << ", j = v" << j << "\n";);
if (!e.is_sum())
return;
nex a, b;
// all factors of j go to a, the rest to b
static void pre_split(nex &e, lpvar j, nex &a, nex&b) {
for (const nex & ce: e.children()) {
if ((ce.is_mul() && ce.contains(j)) || (ce.is_var() && ce.var() == j)) {
a.add_child(ce / j);
@ -232,14 +250,42 @@ public:
a.type() = expr_type::SUM;
TRACE("nla_cn_details", tout << "a = " << a << "\n";);
SASSERT(a.children().size() >= 2);
a.simplify();
if (b.children().size() == 1) {
nex t = b.children()[0];
b = t;
} else if (b.children().size() > 1) {
b.type() = expr_type::SUM;
}
}
static void update_front_with_split_with_non_empty_b(nex& e, lpvar j, vector<nex*> & front, nex& a, nex& b) {
nex f;
bool a_has_f = extract_common_factor(&a, f, get_mult_occurences(a));
SASSERT(a.is_sum());
if (a_has_f) {
TRACE("nla_cn", tout << "a=" << a << ", f=" << f << "\n";);
a /= f;
e = nex::sum(nex::mul(nex::var(j), f, a), b);
TRACE("nla_cn", tout << "a = " << a << ", e = " << e << "\n";);
auto& jfa = e.children()[0];
SASSERT(jfa.size() == 3);
front.push_back(&(jfa.children()[2]));
front.push_back(&e); // e might have its own cross nested form
} else {
TRACE("nla_cn_details", tout << "b = " << b << "\n";);
e = nex::sum(nex::mul(nex::var(j), a), b);
front.push_back(&(e.children()[0].children()[1]));
TRACE("nla_cn_details", tout << "push to front " << e.children()[0].children()[1] << "\n";);
}
if (b.is_sum()) {
front.push_back(&(e.children()[1]));
TRACE("nla_cn_details", tout << "push to front " << e.children()[1] << "\n";);
}
}
static void update_front_with_split(nex& e, lpvar j, vector<nex*> & front, nex& a, nex& b) {
if (b.is_undef()) {
SASSERT(b.children().size() == 0);
e = nex(expr_type::MUL);
@ -249,19 +295,18 @@ public:
front.push_back(&e.children().back());
TRACE("nla_cn_details", tout << "push to front " << e.children().back() << "\n";);
}
} else {
TRACE("nla_cn_details", tout << "b = " << b << "\n";);
e = nex::sum(nex::mul(nex::var(j), a), b);
if (a.is_sum()) {
front.push_back(&(e.children()[0].children()[1]));
TRACE("nla_cn_details", tout << "push to front " << e.children()[0].children()[1] << "\n";);
}
if (b.is_sum()) {
front.push_back(&(e.children()[1]));
TRACE("nla_cn_details", tout << "push to front " << e.children()[1] << "\n";);
}
update_front_with_split_with_non_empty_b(e, j, front, a, b);
}
}
static void split_with_var(nex& e, lpvar j, vector<nex*> & front) {
TRACE("nla_cn_details", tout << "e = " << e << ", j = v" << j << "\n";);
if (!e.is_sum())
return;
nex a, b;
pre_split(e, j, a, b);
update_front_with_split(e, j, front, a, b);
}
std::set<lpvar> get_vars_of_expr(const nex &e ) const {
std::set<lpvar> r;