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remove lattice component

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Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>
This commit is contained in:
Nikolaj Bjorner 2026-02-19 15:49:45 -08:00
parent 5bd7d93b55
commit 38ce0882db
5 changed files with 1 additions and 409 deletions
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1
src/smt/CMakeLists.txt
View file

@ -58,7 +58,6 @@ z3_add_component(smt
theory_dense_diff_logic.cpp
theory_finite_set.cpp
theory_finite_set_size.cpp
theory_finite_set_lattice_refutation.cpp
theory_diff_logic.cpp
theory_dl.cpp
theory_dummy.cpp

7
src/smt/theory_finite_set.cpp
View file

@ -28,8 +28,7 @@ namespace smt {
theory(ctx, ctx.get_manager().mk_family_id("finite_set")),
u(m),
m_axioms(m), m_rw(m), m_find(*this),
m_cardinality_solver(*this),
m_lattice_refutation(*this)
m_cardinality_solver(*this)
{
// Setup the add_clause callback for axioms
std::function<void(theory_axiom *)> add_clause_fn =
@ -260,8 +259,6 @@ namespace smt {
ctx.push_trail(push_back_vector(m_eqs));
m_find.merge(v1, v2); // triggers merge_eh, which triggers incremental generation of theory axioms
}
if (ctx.get_fparams().m_finite_set_lattice_refutation)
m_lattice_refutation.add_equality(v1, v2);
// Check if Z3 has a boolean variable for it
TRACE(finite_set, tout << "new_eq_eh_r1: " << n1->get_root() << "r2: "<< n2->get_root() <<"\n";);
@ -288,8 +285,6 @@ namespace smt {
ctx.push_trail(push_back_vector(m_diseqs));
m_axioms.extensionality_axiom(e1, e2);
}
if (ctx.get_fparams().m_finite_set_lattice_refutation)
m_lattice_refutation.add_disequality(v1,v2);
}
//

5
src/smt/theory_finite_set.h
View file

@ -72,8 +72,6 @@ For ranges we can adapt a different model construction approach.
When introducing select and map, decidability can be lost.
For Boolean lattice constraints given by equality, subset, strict subset and union, intersections,
the theory solver uses a stand-alone satisfiability checker for Boolean algebras to close branches.
--*/
@ -87,7 +85,6 @@ the theory solver uses a stand-alone satisfiability checker for Boolean algebras
#include "util/union_find.h"
#include "smt/smt_theory.h"
#include "smt/theory_finite_set_size.h"
#include "smt/theory_finite_set_lattice_refutation.h"
#include "model/finite_set_factory.h"
namespace smt {
@ -97,7 +94,6 @@ namespace smt {
using th_union_find = union_find<theory_finite_set>;
friend class theory_finite_set_test;
friend class theory_finite_set_size;
friend class theory_finite_set_lattice_refutation;
friend struct finite_set_value_proc;
struct var_data {
@ -141,7 +137,6 @@ namespace smt {
th_union_find m_find;
theory_clauses m_clauses;
theory_finite_set_size m_cardinality_solver;
theory_finite_set_lattice_refutation m_lattice_refutation;
finite_set_factory *m_factory = nullptr;
obj_map<enode, obj_map<enode, bool> *> m_set_members;
ptr_vector<func_decl> m_set_in_decls;

318
src/smt/theory_finite_set_lattice_refutation.cpp
View file

@ -1,318 +0,0 @@
/*++
Copyright (c) 2025 Lorenz Winkler
Module Name:
theory_finite_set_lattice_refutation.cpp
--*/
#include "smt/theory_finite_set_lattice_refutation.h"
#include "smt/smt_theory.h"
#include "smt/theory_finite_set.h"
#include "smt/smt_context.h"
#include <iostream>
const int NUM_WORDS = 5;
// some example have shown, the introduction of large conflict clauses can severely slow down refutation
const int MAX_DECISION_LITERALS = 10;
namespace smt {
reachability_matrix::reachability_matrix(context &ctx, theory_finite_set_lattice_refutation &t_lattice)
: reachable(NUM_WORDS * NUM_WORDS * 64, (uint64_t)0),
links(NUM_WORDS * NUM_WORDS * 64 * 64, {nullptr, nullptr}),
link_dls(NUM_WORDS * NUM_WORDS * 64 * 64, (uint64_t)0),
non_links(NUM_WORDS * NUM_WORDS * 64, (uint64_t)0),
non_link_justifications(NUM_WORDS * NUM_WORDS * 64 * 64, {nullptr, nullptr}),
largest_var(0),
max_size(NUM_WORDS * 64),
ctx(ctx),
t_lattice_refutation(t_lattice) {}
int reachability_matrix::get_max_var() {
return largest_var;
}
inline int reachability_matrix::get_word_index(int row, int col) const {
return (row * NUM_WORDS) + (col / 64);
};
inline uint64_t reachability_matrix::get_bitmask(int col) const {
return 1ull << (col % 64);
};
bool reachability_matrix::is_reachability_forbidden(theory_var source, theory_var dest) {
return non_links[get_word_index(source, dest)] & get_bitmask(dest);
}
bool reachability_matrix::in_bounds(theory_var source, theory_var dest) {
return source >= 0 && dest >= 0 && source < max_size && dest < max_size;
}
bool reachability_matrix::is_reachable(theory_var source, theory_var dest) const {
return reachable[get_word_index(source, dest)] & get_bitmask(dest);
}
bool reachability_matrix::is_linked(theory_var source, theory_var dest) {
return links[source * max_size + dest].first != nullptr;
}
bool reachability_matrix::bitwise_or_rows(int source_dest, int source) {
bool changes = false;
for (int i = 0; i < NUM_WORDS; i++) {
uint64_t old_value = reachable[source_dest * NUM_WORDS + i];
uint64_t new_value = reachable[source_dest * NUM_WORDS + i] | reachable[source * NUM_WORDS + i];
if (old_value == new_value) {
continue;
}
ctx.push_trail(value_trail(reachable[source_dest * NUM_WORDS + i]));
reachable[source_dest * NUM_WORDS + i] = new_value;
changes = true;
check_reachability_conflict_word(source_dest, i);
}
return changes;
}
bool reachability_matrix::set_reachability(theory_var source, theory_var dest, enode_pair reachability_witness) {
if (!in_bounds(source, dest) || is_reachable(source, dest)) {
return false;
}
ctx.push_trail(value_trail(largest_var));
largest_var = std::max({largest_var, source, dest});
int word_idx = get_word_index(source, dest);
ctx.push_trail(value_trail(reachable[word_idx]));
reachable[word_idx] |= get_bitmask(dest);
ctx.push_trail(value_trail(links[source * max_size + dest]));
links[source * max_size + dest] = reachability_witness;
ctx.push_trail(value_trail(link_dls[source * max_size + dest]));
TRACE(finite_set, tout << "set_reachability(" << source << "," << dest << "), dl: " << ctx.get_scope_level());
link_dls[source * max_size + dest] = ctx.get_scope_level();
check_reachability_conflict(source, dest);
// update reachability of source
bitwise_or_rows(source, dest);
for (int i = 0; i <= largest_var; i++) { // update reachability of i to the nodes reachable from dest
if (!is_reachable(i, source) || i == source) {
continue;
}
bitwise_or_rows(i, source);
}
if (conflict_word >= 0 && conflict_row >= 0) {
for (int i = conflict_word * 64; i < conflict_word * 64 + 64; i++) {
check_reachability_conflict(conflict_row, i);
}
conflict_word = -1;
conflict_row = -1;
}
return true;
}
bool reachability_matrix::set_non_reachability(theory_var source, theory_var dest,
enode_pair non_reachability_witness) {
if (is_reachability_forbidden(source, dest)) {
return false;
}
ctx.push_trail(value_trail(largest_var));
largest_var = std::max({largest_var, source, dest});
ctx.push_trail(value_trail(non_links[get_word_index(source, dest)]));
non_links[get_word_index(source, dest)] |= get_bitmask(dest);
ctx.push_trail(value_trail(non_link_justifications[source * max_size + dest]));
non_link_justifications[source * max_size + dest] = non_reachability_witness;
check_reachability_conflict(source, dest);
return true;
}
theory_finite_set_lattice_refutation::theory_finite_set_lattice_refutation(theory_finite_set &th)
: m(th.m), ctx(th.ctx), th(th), u(m), bs(m), m_assumption(m), reachability(th.ctx, *this) {}
// determines if the two enodes capture a subset relation:
// checks, whether intersect_expr = intersect(subset, return_value) for some return value
// otherwise return null
enode *theory_finite_set_lattice_refutation::get_superset(enode *subset, enode *intersect_expr) {
expr *arg1 = nullptr, *arg2 = nullptr;
if (u.is_intersect(intersect_expr->get_expr(), arg1, arg2)) {
if (arg1 == subset->get_expr()) {
return ctx.get_enode(arg2);
}
if (arg2 == subset->get_expr()) {
return ctx.get_enode(arg1);
}
}
return nullptr;
}
void theory_finite_set_lattice_refutation::add_equality(theory_var v1, theory_var v2) {
auto n1 = th.get_enode(v1);
auto n2 = th.get_enode(v2);
enode *subset = n1;
enode *superset = get_superset(n1, n2);
if (superset == nullptr) {
subset = n2;
superset = get_superset(n2, n1);
}
if (superset == nullptr) {
add_set_equality(n1, n2);
return;
}
TRACE(finite_set, tout << "new_eq_intersection: " << enode_pp(subset, ctx) << "(" << th.get_th_var(subset)
<< ")" << "\\subseteq " << enode_pp(superset, ctx) << "(" << th.get_th_var(superset)
<< ")");
add_subset(subset->get_th_var(th.get_id()), superset->get_th_var(th.get_id()), {n1, n2});
};
std::pair<vector<enode_pair>, int> reachability_matrix::get_path(theory_var source, theory_var dest) {
SASSERT(is_reachable(source, dest));
vector<enode_pair> path;
vector<bool> visited(max_size, false);
if (source != dest) {
visited[source] = true;
}
int num_decisions = 0;
do {
bool success = false;
// TRACE(finite_set, tout << "get_path:source: "<<source);
for (int i = 0; i <= largest_var; i++) {
if (!visited[i] && is_linked(source, i) && ((is_reachable(i, dest)) || i == dest)) {
path.push_back(links[source * max_size + i]);
if (link_dls[source * max_size + i] != 0) {
num_decisions += 1;
}
source = i;
visited[source] = true;
success = true;
break;
}
}
SASSERT(success);
} while (source != dest);
TRACE(finite_set, tout << "get_path_num_decisions: " << num_decisions);
return {std::move(path), num_decisions};
}
bool reachability_matrix::check_reachability_conflict(theory_var source, theory_var dest) {
if (is_reachable(source, dest) && is_reachability_forbidden(source, dest)) {
TRACE(finite_set, tout << "found_conflict1: " << source << " -> " << dest);
auto [path, num_decisions] = get_path(source, dest);
// TRACE(finite_set, tout << "found path: "<<source<<" -> "<<dest<<" length: "<<path.size());
if (num_decisions <= MAX_DECISION_LITERALS) {
TRACE(finite_set, tout << "num_decisions: " << num_decisions << " path_length: " << path.size());
enode_pair diseq = non_link_justifications[source * max_size + dest];
t_lattice_refutation.trigger_conflict(path, diseq);
}
return true;
}
return false;
}
bool reachability_matrix::check_reachability_conflict_word(int row, int word) {
if (reachable[row * NUM_WORDS + word] & non_links[row * NUM_WORDS + word]) {
// somewhere in this word there is a conflict
conflict_row = row;
conflict_word = word;
return true;
}
return false;
}
void reachability_matrix::display_relations(std::ostream& out) const {
out << "largest_var: " << largest_var << "\n";
for (int i = 0; i < max_size; i++) {
for (int j = 0; j < max_size; j++) {
if ((reachable[get_word_index(i, j)] & get_bitmask(j)) || is_reachable(i, j)) {
out << "reachable: " << i << "->" << j << " :" << is_reachable(i, j) << "\n";
}
}
}
}
void theory_finite_set_lattice_refutation::trigger_conflict(vector<enode_pair> equalities,
enode_pair clashing_disequality) {
auto eq_expr =
m.mk_not(m.mk_eq(clashing_disequality.first->get_expr(), clashing_disequality.second->get_expr()));
auto disequality_literal = ctx.get_literal(eq_expr);
auto j1 = ext_theory_conflict_justification(th.get_id(), ctx, 1, &disequality_literal, equalities.size(),
equalities.data());
auto justification = ctx.mk_justification(j1);
TRACE(finite_set, tout << "conflict_literal: " << disequality_literal);
TRACE(finite_set, tout << "setting_partial_order_conflict");
ctx.set_conflict(justification);
}
void theory_finite_set_lattice_refutation::add_disequality(theory_var v1, theory_var v2) {
auto n1 = th.get_enode(v1);
auto n2 = th.get_enode(v2);
enode *subset = n1;
enode *superset = get_superset(n1, n2);
if (!superset) {
subset = n2;
superset = get_superset(n2, n1);
}
if (!superset)
return;
TRACE(finite_set, tout << "new_diseq_intersection: " << enode_pp(subset, ctx) << "(" << th.get_th_var(subset)
<< ")" << "\\not\\subseteq " << enode_pp(superset, ctx) << "(" << th.get_th_var(superset)
<< ")");
add_not_subset(subset->get_th_var(th.get_id()), superset->get_th_var(th.get_id()), {n1, n2});
};
void theory_finite_set_lattice_refutation::add_subset(theory_var subset_th, theory_var superset_th,
enode_pair justifying_equality) {
if (!reachability.in_bounds(subset_th, superset_th)) {
return;
}
if (subset_th == null_theory_var || superset_th == null_theory_var) {
return;
}
reachability.set_reachability(subset_th, superset_th, justifying_equality);
SASSERT(reachability.is_reachable(subset_th, superset_th));
if (reachability.is_reachable(superset_th, subset_th)) {
TRACE(finite_set, tout << "cycle_detected: " << subset_th << " <--> " << superset_th);
auto [path, num_decisions] = reachability.get_path(subset_th, subset_th);
// we propagate the equality
// build justification to be used by all propagated equalities
auto j1 = ctx.mk_justification(
ext_theory_conflict_justification(th.get_id(), ctx, 0, nullptr, path.size(), path.data()));
for (unsigned i = 0; i < path.size() - 1; i++) {
auto set1 = path[i].first;
auto set2 = path[i + 1].first;
ctx.add_eq(set1, set2, eq_justification(j1));
TRACE(finite_set, tout << "added_equality: " << set1 << " == " << set2);
}
}
};
void theory_finite_set_lattice_refutation::add_not_subset(theory_var subset_th, theory_var superset_th,
enode_pair justifying_disequality) {
if (!reachability.in_bounds(subset_th, superset_th)) {
return;
}
if (subset_th == null_theory_var || superset_th == null_theory_var) {
return;
}
reachability.set_non_reachability(subset_th, superset_th, justifying_disequality);
SASSERT(reachability.is_reachability_forbidden(subset_th, superset_th));
}
void theory_finite_set_lattice_refutation::add_set_equality(enode *set1, enode *set2) {
theory_var set1_th = set1->get_th_var(th.get_id());
theory_var set2_th = set2->get_th_var(th.get_id());
if (!reachability.in_bounds(set1_th, set2_th)) {
return;
}
reachability.set_reachability(set1_th, set2_th, {set1, set2});
SASSERT(reachability.is_reachable(set1_th, set2_th));
reachability.set_reachability(set2_th, set1_th, {set2, set1});
SASSERT(reachability.is_reachable(set2_th, set1_th));
}
} // namespace smt

79
src/smt/theory_finite_set_lattice_refutation.h
View file

@ -1,79 +0,0 @@
/*++
Copyright (c) 2025 Lorenz Winkler
Module Name:
theory_finite_lattice_refutation.h
--*/
#pragma once
#include "ast/finite_set_decl_plugin.h"
#include "smt/smt_theory.h"
namespace smt {
class context;
class theory_finite_set;
class theory_finite_set_lattice_refutation;
class reachability_matrix {
svector<uint64_t> reachable; // V x V -> bitset of reachable nodes
enode_pair_vector links; // V x V -> enode_pair justifying the link
svector<uint64_t> link_dls; // V x V -> decision level when the link was added
svector<uint64_t> non_links; // V x V -> bitset of non-reachable nodes
enode_pair_vector non_link_justifications; // V x V -> enode_pair justifying the non-link
int largest_var;
int max_size;
context &ctx;
theory_finite_set_lattice_refutation &t_lattice_refutation;
int conflict_row = -1;
int conflict_word = -1;
// sets source_dest |= dest, and pushing the changed words to the trail
bool bitwise_or_rows(int source_dest, int source);
inline int get_word_index(int row, int col) const;
inline uint64_t get_bitmask(int col) const;
public:
std::pair<vector<enode_pair>, int> get_path(theory_var source, theory_var dest);
reachability_matrix(context &ctx, theory_finite_set_lattice_refutation &t_lattice);
bool in_bounds(theory_var source, theory_var dest);
bool is_reachable(theory_var source, theory_var dest) const;
bool is_reachability_forbidden(theory_var source, theory_var dest);
bool is_linked(theory_var source, theory_var dest);
bool check_reachability_conflict(theory_var source, theory_var dest);
bool check_reachability_conflict_word(int row, int word);
bool set_reachability(theory_var source, theory_var dest, enode_pair reachability_witness);
bool set_non_reachability(theory_var source, theory_var dest, enode_pair non_reachability_witness);
int get_max_var();
void display_relations(std::ostream& out) const;
};
class theory_finite_set_lattice_refutation {
ast_manager &m;
context &ctx;
theory_finite_set &th;
finite_set_util u;
expr_ref_vector bs;
expr_ref m_assumption;
reachability_matrix reachability;
enode *get_superset(enode *, enode *);
void add_subset(theory_var subset, theory_var superset, enode_pair justifying_equality);
void add_not_subset(theory_var subset, theory_var superset, enode_pair justifying_disequality);
void propagate_new_subset(theory_var v1, theory_var v2);
void add_set_equality(enode *set1, enode *set2);
public:
void trigger_conflict(vector<enode_pair> equalities, enode_pair clashing_disequality);
theory_finite_set_lattice_refutation(theory_finite_set &th);
void add_equality(theory_var v1, theory_var v2);
void add_disequality(theory_var v1, theory_var v2);
};
} // namespace smt