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re-organize muz_qe into separate units

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Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>
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Nikolaj Bjorner 2013-08-28 21:20:24 -07:00
parent 4597872be8
commit 0d56499e2d
131 changed files with 994 additions and 20069 deletions
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src/muz/transforms/dl_mk_quantifier_abstraction.cpp Normal file
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/*++
Copyright (c) 2013 Microsoft Corporation
Module Name:
dl_mk_quantifier_abstraction.cpp
Abstract:
Create quantified Horn clauses from benchmarks with arrays.
Author:
Ken McMillan
Andrey Rybalchenko
Nikolaj Bjorner (nbjorner) 2013-04-02
Revision History:
--*/
#include "dl_mk_quantifier_abstraction.h"
#include "dl_context.h"
#include "expr_safe_replace.h"
#include "expr_abstract.h"
namespace datalog {
// model converter:
// Given model for P^(x, y, i, a[i])
// create model: P(x,y,a) == forall i . P^(x,y,i,a[i])
// requires substitution and list of bound variables.
class mk_quantifier_abstraction::qa_model_converter : public model_converter {
ast_manager& m;
func_decl_ref_vector m_old_funcs;
func_decl_ref_vector m_new_funcs;
vector<expr_ref_vector> m_subst;
vector<sort_ref_vector> m_sorts;
vector<svector<bool> > m_bound;
public:
qa_model_converter(ast_manager& m):
m(m), m_old_funcs(m), m_new_funcs(m) {}
virtual ~qa_model_converter() {}
virtual model_converter * translate(ast_translation & translator) {
return alloc(qa_model_converter, m);
}
void insert(func_decl* old_p, func_decl* new_p, expr_ref_vector& sub, sort_ref_vector& sorts, svector<bool> const& bound) {
m_old_funcs.push_back(old_p);
m_new_funcs.push_back(new_p);
m_subst.push_back(sub);
m_bound.push_back(bound);
m_sorts.push_back(sorts);
}
virtual void operator()(model_ref & old_model) {
model_ref new_model = alloc(model, m);
for (unsigned i = 0; i < m_new_funcs.size(); ++i) {
func_decl* p = m_new_funcs[i].get();
func_decl* q = m_old_funcs[i].get();
expr_ref_vector const& sub = m_subst[i];
sort_ref_vector const& sorts = m_sorts[i];
svector<bool> const& is_bound = m_bound[i];
func_interp* f = old_model->get_func_interp(p);
expr_ref body(m);
unsigned arity_p = p->get_arity();
unsigned arity_q = q->get_arity();
SASSERT(0 < arity_p);
func_interp* g = alloc(func_interp, m, arity_q);
if (f) {
body = f->get_interp();
SASSERT(!f->is_partial());
SASSERT(body);
}
else {
body = m.mk_false();
}
// Create quantifier wrapper around body.
TRACE("dl", tout << mk_pp(body, m) << "\n";);
// 1. replace variables by the compound terms from
// the original predicate.
expr_safe_replace rep(m);
for (unsigned i = 0; i < sub.size(); ++i) {
rep.insert(m.mk_var(i, m.get_sort(sub[i])), sub[i]);
}
rep(body);
rep.reset();
TRACE("dl", tout << mk_pp(body, m) << "\n";);
// 2. replace bound variables by constants.
expr_ref_vector consts(m), bound(m), free(m);
svector<symbol> names;
ptr_vector<sort> bound_sorts;
for (unsigned i = 0; i < sorts.size(); ++i) {
sort* s = sorts[i];
consts.push_back(m.mk_fresh_const("C", s));
rep.insert(m.mk_var(i, s), consts.back());
if (is_bound[i]) {
bound.push_back(consts.back());
names.push_back(symbol(i));
bound_sorts.push_back(s);
}
else {
free.push_back(consts.back());
}
}
rep(body);
rep.reset();
TRACE("dl", tout << mk_pp(body, m) << "\n";);
// 3. abstract and quantify those variables that should be bound.
expr_abstract(m, 0, bound.size(), bound.c_ptr(), body, body);
body = m.mk_forall(names.size(), bound_sorts.c_ptr(), names.c_ptr(), body);
TRACE("dl", tout << mk_pp(body, m) << "\n";);
// 4. replace remaining constants by variables.
for (unsigned i = 0; i < free.size(); ++i) {
rep.insert(free[i].get(), m.mk_var(i, m.get_sort(free[i].get())));
}
rep(body);
g->set_else(body);
TRACE("dl", tout << mk_pp(body, m) << "\n";);
new_model->register_decl(q, g);
}
old_model = new_model;
}
};
mk_quantifier_abstraction::mk_quantifier_abstraction(
context & ctx, unsigned priority):
plugin(priority),
m(ctx.get_manager()),
m_ctx(ctx),
a(m),
m_refs(m) {
}
mk_quantifier_abstraction::~mk_quantifier_abstraction() {
}
func_decl* mk_quantifier_abstraction::declare_pred(rule_set const& rules, rule_set& dst, func_decl* old_p) {
if (rules.is_output_predicate(old_p)) {
dst.inherit_predicate(rules, old_p, old_p);
return 0;
}
unsigned sz = old_p->get_arity();
unsigned num_arrays = 0;
for (unsigned i = 0; i < sz; ++i) {
if (a.is_array(old_p->get_domain(i))) {
num_arrays++;
}
}
if (num_arrays == 0) {
return 0;
}
func_decl* new_p = 0;
if (!m_old2new.find(old_p, new_p)) {
expr_ref_vector sub(m), vars(m);
svector<bool> bound;
sort_ref_vector domain(m), sorts(m);
expr_ref arg(m);
for (unsigned i = 0; i < sz; ++i) {
sort* s0 = old_p->get_domain(i);
unsigned lookahead = 0;
sort* s = s0;
while (a.is_array(s)) {
lookahead += get_array_arity(s);
s = get_array_range(s);
}
arg = m.mk_var(bound.size() + lookahead, s0);
s = s0;
while (a.is_array(s)) {
unsigned arity = get_array_arity(s);
expr_ref_vector args(m);
for (unsigned j = 0; j < arity; ++j) {
sort* s1 = get_array_domain(s, j);
domain.push_back(s1);
args.push_back(m.mk_var(bound.size(), s1));
bound.push_back(true);
sorts.push_back(s1);
}
arg = mk_select(arg, args.size(), args.c_ptr());
s = get_array_range(s);
}
domain.push_back(s);
bound.push_back(false);
sub.push_back(arg);
sorts.push_back(s0);
}
SASSERT(old_p->get_range() == m.mk_bool_sort());
new_p = m.mk_func_decl(old_p->get_name(), domain.size(), domain.c_ptr(), old_p->get_range());
m_refs.push_back(new_p);
m_ctx.register_predicate(new_p, false);
if (m_mc) {
m_mc->insert(old_p, new_p, sub, sorts, bound);
}
m_old2new.insert(old_p, new_p);
}
return new_p;
}
app_ref mk_quantifier_abstraction::mk_head(rule_set const& rules, rule_set& dst, app* p, unsigned idx) {
func_decl* new_p = declare_pred(rules, dst, p->get_decl());
if (!new_p) {
return app_ref(p, m);
}
expr_ref_vector args(m);
expr_ref arg(m);
unsigned sz = p->get_num_args();
for (unsigned i = 0; i < sz; ++i) {
arg = p->get_arg(i);
sort* s = m.get_sort(arg);
while (a.is_array(s)) {
unsigned arity = get_array_arity(s);
for (unsigned j = 0; j < arity; ++j) {
args.push_back(m.mk_var(idx++, get_array_domain(s, j)));
}
arg = mk_select(arg, arity, args.c_ptr()+args.size()-arity);
s = get_array_range(s);
}
args.push_back(arg);
}
TRACE("dl",
tout << mk_pp(new_p, m) << "\n";
for (unsigned i = 0; i < args.size(); ++i) {
tout << mk_pp(args[i].get(), m) << "\n";
});
return app_ref(m.mk_app(new_p, args.size(), args.c_ptr()), m);
}
app_ref mk_quantifier_abstraction::mk_tail(rule_set const& rules, rule_set& dst, app* p) {
func_decl* old_p = p->get_decl();
func_decl* new_p = declare_pred(rules, dst, old_p);
if (!new_p) {
return app_ref(p, m);
}
SASSERT(new_p->get_arity() > old_p->get_arity());
unsigned num_extra_args = new_p->get_arity() - old_p->get_arity();
var_shifter shift(m);
expr_ref p_shifted(m);
shift(p, num_extra_args, p_shifted);
app* ps = to_app(p_shifted);
expr_ref_vector args(m);
app_ref_vector pats(m);
sort_ref_vector vars(m);
svector<symbol> names;
expr_ref arg(m);
unsigned idx = 0;
unsigned sz = p->get_num_args();
for (unsigned i = 0; i < sz; ++i) {
arg = ps->get_arg(i);
sort* s = m.get_sort(arg);
bool is_pattern = false;
while (a.is_array(s)) {
is_pattern = true;
unsigned arity = get_array_arity(s);
for (unsigned j = 0; j < arity; ++j) {
vars.push_back(get_array_domain(s, j));
names.push_back(symbol(idx));
args.push_back(m.mk_var(idx++, vars.back()));
}
arg = mk_select(arg, arity, args.c_ptr()+args.size()-arity);
s = get_array_range(s);
}
if (is_pattern) {
pats.push_back(to_app(arg));
}
args.push_back(arg);
}
expr* pat = 0;
expr_ref pattern(m);
pattern = m.mk_pattern(pats.size(), pats.c_ptr());
pat = pattern.get();
app_ref result(m);
symbol qid, skid;
result = m.mk_app(new_p, args.size(), args.c_ptr());
result = m.mk_eq(m.mk_forall(vars.size(), vars.c_ptr(), names.c_ptr(), result, 1, qid, skid, 1, &pat), m.mk_true());
return result;
}
expr * mk_quantifier_abstraction::mk_select(expr* arg, unsigned num_args, expr* const* args) {
ptr_vector<expr> args2;
args2.push_back(arg);
args2.append(num_args, args);
return a.mk_select(args2.size(), args2.c_ptr());
}
rule_set * mk_quantifier_abstraction::operator()(rule_set const & source) {
TRACE("dl", tout << "quantify " << source.get_num_rules() << " " << m_ctx.get_params().quantify_arrays() << "\n";);
if (!m_ctx.get_params().quantify_arrays()) {
return 0;
}
unsigned sz = source.get_num_rules();
for (unsigned i = 0; i < sz; ++i) {
rule& r = *source.get_rule(i);
if (r.has_negation()) {
return 0;
}
}
m_refs.reset();
m_old2new.reset();
m_new2old.reset();
rule_manager& rm = source.get_rule_manager();
rule_ref new_rule(rm);
expr_ref_vector tail(m);
app_ref head(m);
expr_ref fml(m);
rule_counter& vc = rm.get_counter();
if (m_ctx.get_model_converter()) {
m_mc = alloc(qa_model_converter, m);
}
rule_set * result = alloc(rule_set, m_ctx);
for (unsigned i = 0; i < sz; ++i) {
tail.reset();
rule & r = *source.get_rule(i);
TRACE("dl", r.display(m_ctx, tout); );
unsigned cnt = vc.get_max_rule_var(r)+1;
unsigned utsz = r.get_uninterpreted_tail_size();
unsigned tsz = r.get_tail_size();
for (unsigned j = 0; j < utsz; ++j) {
tail.push_back(mk_tail(source, *result, r.get_tail(j)));
}
for (unsigned j = utsz; j < tsz; ++j) {
tail.push_back(r.get_tail(j));
}
head = mk_head(source, *result, r.get_head(), cnt);
fml = m.mk_implies(m.mk_and(tail.size(), tail.c_ptr()), head);
rule_ref_vector added_rules(rm);
proof_ref pr(m);
rm.mk_rule(fml, pr, *result);
TRACE("dl", result->last()->display(m_ctx, tout););
}
// proof converter: proofs are not necessarily preserved using this transformation.
if (m_old2new.empty()) {
dealloc(result);
dealloc(m_mc);
result = 0;
}
else {
m_ctx.add_model_converter(m_mc);
}
m_mc = 0;
return result;
}
};