mirrors/z3
3
0
Fork 0
mirror of https://github.com/Z3Prover/z3 synced 2025-07-18 02:16:40 +00:00
Code Activity

better proof mining for Farkas

Browse source 
Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>
This commit is contained in:
Nikolaj Bjorner 2012-10-13 10:13:14 -07:00
parent 8121386d5e
commit 9828a29b68
6 changed files with 119 additions and 115 deletions
Download patch file Download diff file Expand all files Collapse all files

96
lib/pdr_farkas_learner.cpp
View file

@ -512,12 +512,10 @@ namespace pdr {
for_each_expr(collect_proc, *it);
}
proof_ref tmp(root, m);
proof_utils::reduce_hypotheses(tmp);
IF_VERBOSE(2, verbose_stream() << "Elim Hyps:\n" << mk_ismt2_pp(tmp, m) << "\n";);
proof_ref pr(root, m);
permute_unit_resolution(pr);
proof_utils::reduce_hypotheses(pr);
IF_VERBOSE(2, verbose_stream() << "Elim Hyps:\n" << mk_ismt2_pp(pr, m) << "\n";);
proof_utils::permute_unit_resolution(pr);
ptr_vector<expr_set> hyprefs;
obj_map<expr, expr_set*> hypmap;
@ -751,94 +749,6 @@ namespace pdr {
}
}
// permute unit resolution over Theory lemmas to track premises.
void farkas_learner::permute_unit_resolution(proof_ref& pr) {
expr_ref_vector refs(pr.get_manager());
obj_map<proof,proof*> cache;
permute_unit_resolution(refs, cache, pr);
}
void farkas_learner::permute_unit_resolution(expr_ref_vector& refs, obj_map<proof,proof*>& cache, proof_ref& pr) {
ast_manager& m = pr.get_manager();
proof* pr2 = 0;
proof_ref_vector parents(m);
proof_ref prNew(pr);
if (cache.find(pr, pr2)) {
pr = pr2;
return;
}
for (unsigned i = 0; i < m.get_num_parents(pr); ++i) {
prNew = m.get_parent(pr, i);
permute_unit_resolution(refs, cache, prNew);
parents.push_back(prNew);
}
prNew = pr;
if (pr->get_decl_kind() == PR_UNIT_RESOLUTION &&
parents[0]->get_decl_kind() == PR_TH_LEMMA) {
/*
Unit resolution:
T1: (or l_1 ... l_n l_1' ... l_m')
T2: (not l_1)
...
T(n+1): (not l_n)
[unit-resolution T1 ... T(n+1)]: (or l_1' ... l_m')
Th lemma:
T1: (not l_1)
...
Tn: (not l_n)
[th-lemma T1 ... Tn]: (or l_{n+1} ... l_m)
Such that (or l_1 .. l_n l_{n+1} .. l_m) is a theory axiom.
Implement conversion:
T1 |- not l_1 ... Tn |- not l_n
------------------------------- TH_LEMMA
(or k_1 .. k_m j_1 ... j_m) S1 |- not k_1 ... Sm |- not k_m
-------------------------------------------------------------- UNIT_RESOLUTION
(or j_1 .. j_m)
|->
T1 |- not l_1 ... Tn |- not l_n S1 |- not k_1 ... Sm |- not k_m
---------------------------------------------------------------- TH_LEMMA
(or j_1 .. j_m)
*/
proof_ref_vector premises(m);
proof* thLemma = parents[0].get();
for (unsigned i = 0; i < m.get_num_parents(thLemma); ++i) {
premises.push_back(m.get_parent(thLemma, i));
}
for (unsigned i = 1; i < parents.size(); ++i) {
premises.push_back(parents[i].get());
}
parameter const* params = thLemma->get_decl()->get_parameters();
unsigned num_params = thLemma->get_decl()->get_num_parameters();
SASSERT(params[0].is_symbol());
family_id tid = m.get_family_id(params[0].get_symbol());
SASSERT(tid != null_family_id);
prNew = m.mk_th_lemma(tid, m.get_fact(pr),
premises.size(), premises.c_ptr(), num_params-1, params+1);
}
else {
ptr_vector<expr> args;
for (unsigned i = 0; i < parents.size(); ++i) {
args.push_back(parents[i].get());
}
if (m.has_fact(pr)) {
args.push_back(m.get_fact(pr));
}
prNew = m.mk_app(pr->get_decl(), args.size(), args.c_ptr());
}
cache.insert(pr, prNew);
refs.push_back(prNew);
pr = prNew;
}
bool farkas_learner::is_farkas_lemma(ast_manager& m, expr* e) {
app * a;