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use array interpretations whenever possible for #2378. Also strengthen equality test for lambda

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Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>
This commit is contained in:
Nikolaj Bjorner 2019-07-14 09:23:29 -04:00
parent 3ca32efd18
commit 4deb9d2af2
6 changed files with 124 additions and 100 deletions
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22
src/ast/rewriter/array_rewriter.cpp
View file

@ -19,6 +19,7 @@ Notes:
#include "ast/rewriter/array_rewriter.h"
#include "ast/rewriter/array_rewriter_params.hpp"
#include "ast/ast_lt.h"
#include "ast/ast_util.h"
#include "ast/ast_pp.h"
#include "ast/rewriter/var_subst.h"
@ -566,6 +567,15 @@ bool array_rewriter::has_index_set(expr* e, expr_ref& else_case, vector<expr_ref
else_case = m().mk_false();
return true;
}
if (!is_ground(e) && m().is_and(e)) {
for (expr* arg : *to_app(e)) {
if (!add_store(args, num_idxs, arg, m().mk_true(), stores)) {
return false;
}
}
else_case = m().mk_true();
return true;
}
while (!is_ground(e) && m().is_ite(e, e1, store_val, e3) && is_ground(store_val)) {
if (!add_store(args, num_idxs, e1, store_val, stores)) {
return false;
@ -584,13 +594,16 @@ bool array_rewriter::add_store(expr_ref_vector& args, unsigned num_idxs, expr* e
ptr_vector<expr> eqs;
args.reset();
args.resize(num_idxs + 1, nullptr);
bool is_not = m().is_bool(store_val) && m().is_not(e, e);
eqs.push_back(e);
for (unsigned i = 0; i < eqs.size(); ++i) {
e = eqs[i];
if (m().is_and(e)) {
eqs.append(to_app(e)->get_num_args(), to_app(e)->get_args());
continue;
}
else if (m().is_eq(e, e1, e2)) {
if (m().is_eq(e, e1, e2)) {
if (is_var(e2)) {
std::swap(e1, e2);
}
@ -601,11 +614,16 @@ bool array_rewriter::add_store(expr_ref_vector& args, unsigned num_idxs, expr* e
else {
return false;
}
}
continue;
}
return false;
}
for (unsigned i = 0; i < num_idxs; ++i) {
if (!args.get(i)) return false;
}
if (is_not) {
store_val = mk_not(m(), store_val);
}
args[num_idxs] = store_val;
stores.push_back(args);
return true;

98
src/model/func_interp.cpp
View file

@ -75,7 +75,8 @@ func_interp::func_interp(ast_manager & m, unsigned arity):
m_arity(arity),
m_else(nullptr),
m_args_are_values(true),
m_interp(nullptr) {
m_interp(nullptr),
m_array_interp(nullptr) {
}
func_interp::~func_interp() {
@ -84,6 +85,7 @@ func_interp::~func_interp() {
}
m_manager.dec_ref(m_else);
m_manager.dec_ref(m_interp);
m_manager.dec_ref(m_array_interp);
}
func_interp * func_interp::copy() const {
@ -98,7 +100,9 @@ func_interp * func_interp::copy() const {
void func_interp::reset_interp_cache() {
m_manager.dec_ref(m_interp);
m_manager.dec_ref(m_array_interp);
m_interp = nullptr;
m_array_interp = nullptr;
}
bool func_interp::is_fi_entry_expr(expr * e, ptr_vector<expr> & args) {
@ -317,36 +321,6 @@ bool func_interp::is_identity() const {
return (sz.size() == m_entries.size() + 1);
}
expr_ref func_interp::get_array_interp(sort_ref_vector const& domain) const {
if (m_else == nullptr)
return expr_ref(m_manager);
if (!is_ground(m_else)) {
return expr_ref(m_manager);
}
array_util autil(m_manager);
sort_ref A(autil.mk_array_sort(domain.size(), domain.c_ptr(), m_manager.get_sort(m_else)), m_manager);
expr_ref r(autil.mk_const_array(A, m_else), m_manager);
expr_ref_vector args(m_manager);
for (func_entry * curr : m_entries) {
expr * res = curr->get_result();
if (m_else == res) {
continue;
}
args.reset();
args.push_back(r);
for (unsigned i = 0; i < m_arity; i++) {
expr* arg = curr->get_arg(i);
if (!is_ground(arg)) {
return expr_ref(m_manager);
}
args.push_back(arg);
}
args.push_back(res);
r = autil.mk_store(args.size(), args.c_ptr());
}
return r;
}
expr * func_interp::get_interp_core() const {
if (m_else == nullptr)
@ -382,6 +356,57 @@ expr * func_interp::get_interp_core() const {
return r;
}
expr* func_interp::get_array_interp_core(func_decl * f) const {
if (m_else == nullptr)
return nullptr;
ptr_vector<sort> domain;
for (sort* s : *f) {
domain.push_back(s);
}
expr* r;
bool ground = is_ground(m_else);
for (func_entry * curr : m_entries) {
ground &= is_ground(curr->get_result());
for (unsigned i = 0; i < m_arity; i++) {
ground &= is_ground(curr->get_arg(i));
}
}
if (!ground) {
r = get_interp();
if (!r) return r;
sort_ref_vector vars(m_manager);
svector<symbol> var_names;
for (unsigned i = 0; i < m_arity; ++i) {
var_names.push_back(symbol(i));
vars.push_back(domain.get(m_arity - i - 1));
}
r = m_manager.mk_lambda(vars.size(), vars.c_ptr(), var_names.c_ptr(), r);
return r;
}
expr_ref_vector args(m_manager);
array_util autil(m_manager);
sort_ref A(autil.mk_array_sort(domain.size(), domain.c_ptr(), m_manager.get_sort(m_else)), m_manager);
r = autil.mk_const_array(A, m_else);
for (func_entry * curr : m_entries) {
expr * res = curr->get_result();
if (m_else == res) {
continue;
}
args.reset();
args.push_back(r);
for (unsigned i = 0; i < m_arity; i++) {
args.push_back(curr->get_arg(i));
}
args.push_back(res);
r = autil.mk_store(args.size(), args.c_ptr());
}
return r;
}
expr * func_interp::get_interp() const {
if (m_interp != nullptr)
return m_interp;
@ -393,6 +418,17 @@ expr * func_interp::get_interp() const {
return r;
}
expr * func_interp::get_array_interp(func_decl * f) const {
if (m_array_interp != nullptr)
return m_array_interp;
expr* r = get_array_interp_core(f);
if (r != nullptr) {
const_cast<func_interp*>(this)->m_array_interp = r;
m_manager.inc_ref(m_array_interp);
}
return r;
}
func_interp * func_interp::translate(ast_translation & translator) const {
func_interp * new_fi = alloc(func_interp, translator.to(), m_arity);

6
src/model/func_interp.h
View file

@ -73,10 +73,14 @@ class func_interp {
expr * m_interp; //!< cache for representing the whole interpretation as a single expression (it uses ite terms).
expr * m_array_interp; // <! interp with lambda abstraction
void reset_interp_cache();
expr * get_interp_core() const;
expr * get_array_interp_core(func_decl * f) const;
public:
func_interp(ast_manager & m, unsigned arity);
~func_interp();
@ -112,7 +116,7 @@ public:
expr * get_interp() const;
expr_ref get_array_interp(sort_ref_vector const& domain) const;
expr * get_array_interp(func_decl* f) const;
func_interp * translate(ast_translation & translator) const;

16
src/model/model.cpp
View file

@ -418,10 +418,7 @@ expr_ref model::cleanup_expr(top_sort& ts, expr* e, unsigned current_partition)
// only expand auxiliary definitions that occur once.
if (can_inline_def(ts, f)) {
fi = get_func_interp(f);
for (sort* s : *f) {
domain.push_back(s);
}
new_t = fi->get_array_interp(domain);
new_t = fi->get_array_interp(f);
TRACE("model", tout << "array interpretation:" << new_t << "\n";);
}
}
@ -429,17 +426,6 @@ expr_ref model::cleanup_expr(top_sort& ts, expr* e, unsigned current_partition)
if (new_t) {
// noop
}
else if (fi && fi->get_interp()) {
f = autil.get_as_array_func_decl(a);
expr_ref_vector sargs(m);
sort_ref_vector vars(m);
svector<symbol> var_names;
for (unsigned i = 0; i < f->get_arity(); ++i) {
var_names.push_back(symbol(i));
vars.push_back(f->get_domain(f->get_arity() - i - 1));
}
new_t = m.mk_lambda(vars.size(), vars.c_ptr(), var_names.c_ptr(), fi->get_interp());
}
else if (f->is_skolem() && can_inline_def(ts, f) && (fi = get_func_interp(f)) &&
fi->get_interp() && (!ts.partition_ids().find(f, pid) || pid != current_partition)) {
var_subst vs(m, false);

69
src/model/model_evaluator.cpp
View file

@ -150,6 +150,7 @@ struct evaluator_cfg : public default_rewriter_cfg {
expr * val = m_model.get_const_interp(f);
if (val != nullptr) {
result = val;
// return BR_DONE;
return m_ar.is_as_array(val)? BR_REWRITE1 : BR_DONE;
}
else if (m_model_completion) {
@ -243,19 +244,8 @@ struct evaluator_cfg : public default_rewriter_cfg {
result = def;
return BR_DONE;
}
if (get_macro(g, def, q, def_pr)) {
sort_ref_vector sorts(m);
expr_ref_vector vars(m);
svector<symbol> var_names;
unsigned sz = g->get_arity();
for (unsigned i = 0; i < sz; ++i) {
var_names.push_back(symbol(sz - i - 1));
vars.push_back(m.mk_var(sz - i - 1, g->get_domain(i)));
sorts.push_back(g->get_domain(i));
}
var_subst subst(m, false);
result = subst(def, sorts.size(), vars.c_ptr());
result = m.mk_lambda(sorts.size(), sorts.c_ptr(), var_names.c_ptr(), result);
func_interp * fi = m_model.get_func_interp(g);
if (fi && (result = fi->get_array_interp(g))) {
model_evaluator ev(m_model, m_params);
result = ev(result);
m_pinned.push_back(result);
@ -530,47 +520,34 @@ struct evaluator_cfg : public default_rewriter_cfg {
func_decl* f = m_ar.get_as_array_func_decl(to_app(a));
func_interp* g = m_model.get_func_interp(f);
if (!g) return false;
if (!g) return false;
else_case = g->get_else();
if (!else_case) {
TRACE("model_evaluator", tout << "no else case " << mk_pp(a, m) << "\n";);
return false;
}
bool ground = is_ground(else_case);
unsigned sz = g->num_entries();
unsigned arity = f->get_arity();
unsigned base_sz = stores.size();
expr_ref_vector store(m);
for (unsigned i = 0; i < sz; ++i) {
expr_ref_vector store(m);
store.reset();
func_entry const* fe = g->get_entry(i);
store.append(arity, fe->get_args());
store.push_back(fe->get_result());
for (unsigned j = 0; j < store.size(); ++j) {
if (!is_ground(store[j].get())) {
TRACE("model_evaluator", tout << "could not extract array interpretation: " << mk_pp(a, m) << "\n" << mk_pp(store[j].get(), m) << "\n";);
return false;
}
expr* res = fe->get_result();
if (m.are_equal(else_case, res)) {
continue;
}
ground &= is_ground(res);
store.append(g->get_arity(), fe->get_args());
store.push_back(res);
for (expr* arg : store) {
ground &= is_ground(arg);
}
stores.push_back(store);
}
else_case = g->get_else();
if (!else_case) {
TRACE("model_evaluator", tout << "no else case " << mk_pp(a, m) << "\n";
/*model_smt2_pp(tout, m, m_model, 0);*/
);
if (!ground) {
TRACE("model_evaluator", tout << "could not extract ground array interpretation: " << mk_pp(a, m) << "\n";);
return false;
}
if (!is_ground(else_case)) {
TRACE("model_evaluator", tout << "non-ground else case " << mk_pp(a, m) << "\n" << else_case << "\n";);
return false;
}
for (unsigned i = stores.size(); are_values && i > base_sz; ) {
--i;
if (m.are_equal(else_case, stores[i].back())) {
for (unsigned j = i + 1; j < stores.size(); ++j) {
stores[j-1].reset();
stores[j-1].append(stores[j]);
}
stores.pop_back();
continue;
}
are_values &= args_are_values(stores[i], are_unique);
}
TRACE("model_evaluator", tout << "else case: " << mk_pp(else_case, m) << "\n";);
return true;
}
};

13
src/qe/qe_arrays.cpp
View file

@ -515,9 +515,8 @@ namespace qe {
* ...
*/
unsigned get_nesting_depth(app* eq) {
SASSERT(m.is_eq(eq));
expr* lhs = eq->get_arg (0);
expr* rhs = eq->get_arg (1);
expr* lhs = nullptr, *rhs = nullptr;
VERIFY(m.is_eq(eq, lhs, rhs));
bool lhs_has_v = (lhs == m_v || m_has_stores_v.is_marked (lhs));
bool rhs_has_v = (rhs == m_v || m_has_stores_v.is_marked (rhs));
app* store = nullptr;
@ -537,9 +536,13 @@ namespace qe {
}
unsigned nd = 0; // nesting depth
for (nd = 1; m_arr_u.is_store (store); nd++, store = to_app (store->get_arg (0)))
for (nd = 1; m_arr_u.is_store (store); nd++, store = to_app (store->get_arg (0))) {
/* empty */ ;
SASSERT (store == m_v);
}
if (store != m_v) {
TRACE("qe", tout << "not a store " << mk_pp(eq, m) << " " << lhs_has_v << " " << rhs_has_v << " " << mk_pp(m_v, m) << "\n";);
return UINT_MAX;
}
return nd;
}