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https://github.com/Z3Prover/z3
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760 lines
29 KiB
C++
760 lines
29 KiB
C++
/*++
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Copyright (c) 2006 Microsoft Corporation
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Module Name:
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dl_mk_simple_joins.cpp
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Abstract:
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<abstract>
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Author:
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Krystof Hoder 2010-05-20.
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Revision History:
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--*/
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#include<utility>
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#include<sstream>
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#include<limits>
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#include"dl_mk_simple_joins.h"
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#include"dl_relation_manager.h"
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#include"ast_pp.h"
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#include"trace.h"
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namespace datalog {
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mk_simple_joins::mk_simple_joins(context & ctx):
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plugin(1000),
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m_context(ctx),
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rm(ctx.get_rule_manager()) {
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}
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class join_planner {
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typedef float cost;
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class pair_info {
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cost m_total_cost;
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/**
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\brief Number of rules longer than two that contain this pair.
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This number is being updated by \c add_rule and \remove rule. Even though between
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adding a rule and removing it, the length of a rule can decrease without this pair
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being notified about it, it will surely see the decrease from length 3 to 2 which
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the threshold for rule being counted in this counter.
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*/
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unsigned m_consumers;
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bool m_stratified;
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unsigned m_src_stratum;
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public:
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var_idx_set m_all_nonlocal_vars;
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rule_vector m_rules;
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pair_info() : m_consumers(0), m_stratified(true), m_src_stratum(0) {}
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bool can_be_joined() const {
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return m_consumers > 0;
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}
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cost get_cost() const {
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SASSERT(m_consumers > 0);
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cost amortized = m_total_cost/m_consumers;
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if (m_stratified) {
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return amortized * ( (amortized>0) ? (1/16.0f) : 16.0f);
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}
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else {
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return amortized;
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}
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}
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/**
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\brief Add rule \c r among rules interested in current predicate pair.
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The \c pl.m_rule_content entry of the rule has to be properly filled in
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by the time of a call to this function
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*/
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void add_rule(join_planner & pl, app * t1, app * t2, rule * r,
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const var_idx_set & non_local_vars_normalized,
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const var_idx_set & non_local_vars) {
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if (m_rules.empty()) {
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m_total_cost = pl.compute_cost(t1, t2, non_local_vars);
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m_src_stratum = std::max(pl.get_stratum(t1->get_decl()), pl.get_stratum(t2->get_decl()));
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}
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m_rules.push_back(r);
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if (pl.m_rules_content.find(r).size()>2) {
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m_consumers++;
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}
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if (m_stratified) {
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unsigned head_stratum = pl.get_stratum(r->get_decl());
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SASSERT(head_stratum>=m_src_stratum);
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if (head_stratum==m_src_stratum) {
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m_stratified = false;
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}
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}
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idx_set_union(m_all_nonlocal_vars, non_local_vars_normalized);
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}
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/**
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\brief Remove rule from the pair record. Return true if no rules remain
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in the pair, and so it should be removed.
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*/
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bool remove_rule(rule * r, unsigned original_length) {
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VERIFY( remove_from_vector(m_rules, r) );
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if (original_length>2) {
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SASSERT(m_consumers>0);
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m_consumers--;
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}
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SASSERT(!m_rules.empty() || m_consumers==0);
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return m_rules.empty();
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}
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private:
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pair_info & operator=(const pair_info &); //to avoid the implicit one
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};
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typedef std::pair<app*, app*> app_pair;
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typedef pair_hash<obj_ptr_hash<app>, obj_ptr_hash<app> > app_pair_hash;
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typedef map<app_pair, pair_info *, app_pair_hash, default_eq<app_pair> > cost_map;
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typedef map<rule *, ptr_vector<app>, ptr_hash<rule>, ptr_eq<rule> > rule_pred_map;
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typedef ptr_hashtable<rule, rule_hash_proc, default_eq<rule *> > rule_hashtable;
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context & m_context;
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ast_manager & m;
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rule_manager & rm;
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var_subst & m_var_subst;
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rule_set & m_rs_aux_copy; //reference to a rule_set that will allow to ask for stratum levels
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cost_map m_costs;
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ptr_vector<app> m_interpreted;
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rule_pred_map m_rules_content;
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rule_ref_vector m_introduced_rules;
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bool m_modified_rules;
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ast_ref_vector m_pinned;
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mutable ptr_vector<sort> m_vars;
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public:
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join_planner(context & ctx, rule_set & rs_aux_copy)
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: m_context(ctx), m(ctx.get_manager()),
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rm(ctx.get_rule_manager()),
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m_var_subst(ctx.get_var_subst()),
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m_rs_aux_copy(rs_aux_copy),
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m_introduced_rules(ctx.get_rule_manager()),
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m_modified_rules(false),
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m_pinned(ctx.get_manager())
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{
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}
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~join_planner()
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{
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cost_map::iterator it = m_costs.begin();
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cost_map::iterator end = m_costs.end();
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for (; it != end; ++it) {
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dealloc(it->m_value);
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}
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m_costs.reset();
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}
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private:
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void get_normalizer(app * t, unsigned & next_var, expr_ref_vector & result) const {
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SASSERT(result.size()>0);
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unsigned res_ofs = result.size()-1;
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unsigned n=t->get_num_args();
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for(unsigned i=0; i<n; i++) {
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SASSERT(is_var(t->get_arg(i)));
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var * v = to_var(t->get_arg(i));
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unsigned var_idx = v->get_idx();
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if (result[res_ofs-var_idx]==0) {
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result[res_ofs-var_idx]=m.mk_var(next_var, v->get_sort());
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next_var++;
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}
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}
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}
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void get_normalizer(app * t1, app * t2, expr_ref_vector & result) const {
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SASSERT(result.empty());
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if (t1->get_num_args()==0 && t2->get_num_args()==0) {
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return; //nothing to normalize
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}
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SASSERT(!t1->is_ground() || !t2->is_ground());
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unsigned max_var_idx = 0;
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{
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var_idx_set& orig_var_set = rm.collect_vars(t1, t2);
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var_idx_set::iterator ovit = orig_var_set.begin();
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var_idx_set::iterator ovend = orig_var_set.end();
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for(; ovit!=ovend; ++ovit) {
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unsigned var_idx = *ovit;
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if (var_idx>max_var_idx) {
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max_var_idx = var_idx;
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}
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}
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}
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if (t1->get_decl()!=t2->get_decl()) {
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if (t1->get_decl()->get_id()<t2->get_decl()->get_id()) {
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std::swap(t1, t2);
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}
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}
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else {
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int_vector norm1(max_var_idx+1, -1);
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int_vector norm2(max_var_idx+1, -1);
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unsigned n=t1->get_num_args();
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SASSERT(n==t2->get_num_args());
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for(unsigned i=0; i<n; i++) {
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//We assume that the mk_simple_joins transformer is applied after mk_filter_rules,
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//so the only literals which appear in pairs are the ones that contain only variables.
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var * v1 = to_var(t1->get_arg(i));
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var * v2 = to_var(t2->get_arg(i));
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if (v1->get_sort()!=v2->get_sort()) {
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//different sorts mean we can distinguish the two terms
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if (v1->get_sort()->get_id()<v2->get_sort()->get_id()) {
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std::swap(t1, t2);
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}
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break;
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}
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unsigned v1_idx = v1->get_idx();
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unsigned v2_idx = v2->get_idx();
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//since the rules already went through the mk_filter_rules transformer,
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//variables must be linear
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SASSERT(norm1[v1_idx]==-1);
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SASSERT(norm2[v2_idx]==-1);
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if (norm2[v1_idx]!=norm1[v2_idx]) {
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//now we can distinguish the two terms
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if (norm2[v1_idx]<norm1[v2_idx]) {
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std::swap(t1, t2);
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}
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break;
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}
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norm1[v1_idx]=i;
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norm2[v2_idx]=i;
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}
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//if we did not exit the loop prematurely, the two terms are indistinguishable,
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//so the order should not matter
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}
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result.resize(max_var_idx+1, static_cast<expr *>(0));
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unsigned next_var = 0;
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get_normalizer(t1, next_var, result);
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get_normalizer(t2, next_var, result);
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}
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app_pair get_key(app * t1, app * t2) {
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expr_ref_vector norm_subst(m);
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get_normalizer(t1, t2, norm_subst);
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expr_ref t1n_ref(m);
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expr_ref t2n_ref(m);
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m_var_subst(t1, norm_subst.size(), norm_subst.c_ptr(), t1n_ref);
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m_var_subst(t2, norm_subst.size(), norm_subst.c_ptr(), t2n_ref);
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app * t1n = to_app(t1n_ref);
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app * t2n = to_app(t2n_ref);
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if (t1n->get_id() > t2n->get_id()) {
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std::swap(t1n, t2n);
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}
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m_pinned.push_back(t1n);
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m_pinned.push_back(t2n);
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return app_pair(t1n, t2n);
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}
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/**
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\brief Add rule \c r among rules interested in predicate pair \c t1, \c t2.
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The \c m_rule_content entry of the rule \c r has to be properly filled in
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by the time of a call to this function
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*/
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void register_pair(app * t1, app * t2, rule * r, const var_idx_set & non_local_vars) {
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SASSERT(t1!=t2);
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cost_map::entry * e = m_costs.insert_if_not_there2(get_key(t1, t2), 0);
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pair_info * & ptr_inf = e->get_data().m_value;
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if (ptr_inf==0) {
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ptr_inf = alloc(pair_info);
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}
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pair_info & inf = *ptr_inf;
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expr_ref_vector normalizer(m);
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get_normalizer(t1, t2, normalizer);
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unsigned norm_ofs = normalizer.size()-1;
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var_idx_set normalized_vars;
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var_idx_set::iterator vit = non_local_vars.begin();
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var_idx_set::iterator vend = non_local_vars.end();
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for(; vit!=vend; ++vit) {
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unsigned norm_var = to_var(normalizer.get(norm_ofs-*vit))->get_idx();
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normalized_vars.insert(norm_var);
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}
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inf.add_rule(*this, t1, t2, r, normalized_vars, non_local_vars);
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TRACE("dl", tout << mk_pp(t1, m) << " " << mk_pp(t2, m) << " ";
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vit = non_local_vars.begin();
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for (; vit != vend; ++vit) tout << *vit << " ";
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tout << "\n";
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r->display(m_context, tout);
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if (inf.can_be_joined()) tout << "cost: " << inf.get_cost() << "\n";);
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}
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void remove_rule_from_pair(app_pair key, rule * r, unsigned original_len) {
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pair_info * ptr = 0;
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if (m_costs.find(key, ptr) && ptr &&
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ptr->remove_rule(r, original_len)) {
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SASSERT(ptr->m_rules.empty());
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m_costs.remove(key);
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dealloc(ptr);
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}
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}
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void register_rule(rule * r) {
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rule_counter counter;
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counter.count_rule_vars(r, 1);
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ptr_vector<app> & rule_content =
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m_rules_content.insert_if_not_there2(r, ptr_vector<app>())->get_data().m_value;
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SASSERT(rule_content.empty());
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unsigned pos_tail_size=r->get_positive_tail_size();
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for(unsigned i=0; i<pos_tail_size; i++) {
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rule_content.push_back(r->get_tail(i));
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}
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for(unsigned i=0; i+1 < pos_tail_size; i++) {
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app * t1 = r->get_tail(i);
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var_idx_set t1_vars = rm.collect_vars(t1);
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counter.count_vars(t1, -1); //temporarily remove t1 variables from counter
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for(unsigned j=i+1; j<pos_tail_size; j++) {
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app * t2 = r->get_tail(j);
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counter.count_vars(t2, -1); //temporarily remove t2 variables from counter
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var_idx_set scope_vars = rm.collect_vars(t2);
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scope_vars |= t1_vars;
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var_idx_set non_local_vars;
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counter.collect_positive(non_local_vars);
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counter.count_vars(t2, 1); //restore t2 variables in counter
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set_intersection(non_local_vars, scope_vars);
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register_pair(t1, t2, r, non_local_vars);
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}
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counter.count_vars(t1, 1); //restore t1 variables in counter
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}
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}
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bool extract_argument_info(unsigned var_idx, app * t, expr_ref_vector & args,
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ptr_vector<sort> & domain) {
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unsigned n=t->get_num_args();
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for(unsigned i=0; i<n; i++) {
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var * v=to_var(t->get_arg(i));
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if (v->get_idx()==var_idx) {
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args.push_back(v);
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domain.push_back(m.get_sort(v));
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return true;
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}
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}
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return false;
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}
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void join_pair(app_pair pair_key) {
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app * t1 = pair_key.first;
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app * t2 = pair_key.second;
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pair_info* infp = 0;
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if (!m_costs.find(pair_key, infp) || !infp) {
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UNREACHABLE();
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return;
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}
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pair_info & inf = *infp;
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SASSERT(!inf.m_rules.empty());
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var_idx_set & output_vars = inf.m_all_nonlocal_vars;
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expr_ref_vector args(m);
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ptr_vector<sort> domain;
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unsigned arity = output_vars.num_elems();
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idx_set::iterator ovit=output_vars.begin();
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idx_set::iterator ovend=output_vars.end();
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//TODO: improve quadratic complexity
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for(;ovit!=ovend;++ovit) {
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unsigned var_idx=*ovit;
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bool found=extract_argument_info(var_idx, t1, args, domain);
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if (!found) {
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found=extract_argument_info(var_idx, t2, args, domain);
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}
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SASSERT(found);
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}
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SASSERT(args.size()==arity);
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SASSERT(domain.size()==arity);
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rule * one_parent = inf.m_rules.back();
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func_decl* parent_head = one_parent->get_decl();
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const char * one_parent_name = parent_head->get_name().bare_str();
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std::string parent_name;
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if (inf.m_rules.size() > 1) {
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parent_name = one_parent_name + std::string("_and_") + to_string(inf.m_rules.size()-1);
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}
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else {
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parent_name = one_parent_name;
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}
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func_decl * decl = m_context.mk_fresh_head_predicate(
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symbol(parent_name.c_str()), symbol("split"),
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arity, domain.c_ptr(), parent_head);
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app_ref head(m.mk_app(decl, arity, args.c_ptr()), m);
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app * tail[] = {t1, t2};
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rule * new_rule = m_context.get_rule_manager().mk(head, 2, tail, 0);
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//TODO: update accounting so that it can handle multiple parents
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new_rule->set_accounting_parent_object(m_context, one_parent);
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m_introduced_rules.push_back(new_rule);
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//here we copy the inf.m_rules vector because inf.m_rules will get changed
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//in the iteration. Also we use hashtable instead of vector because we do
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//not want to process one rule twice.
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rule_hashtable processed_rules;
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rule_vector rules(inf.m_rules);
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for (unsigned i = 0; i < rules.size(); ++i) {
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rule* r = rules[i];
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if (!processed_rules.contains(r)) {
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apply_binary_rule(r, pair_key, head);
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processed_rules.insert(r);
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}
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}
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// SASSERT(!m_costs.contains(pair_key));
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}
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void replace_edges(rule * r, const ptr_vector<app> & removed_tails,
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const ptr_vector<app> & added_tails0, const ptr_vector<app> & rule_content) {
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SASSERT(removed_tails.size()>=added_tails0.size());
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unsigned len = rule_content.size();
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unsigned original_len = len+removed_tails.size()-added_tails0.size();
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ptr_vector<app> added_tails(added_tails0); //we need a copy since we'll be modifying it
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unsigned rt_sz = removed_tails.size();
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//remove edges between removed tails
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for(unsigned i=0; i<rt_sz; i++) {
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for(unsigned j=i+1; j<rt_sz; j++) {
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app_pair pair_key = get_key(removed_tails[i], removed_tails[j]);
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remove_rule_from_pair(pair_key, r, original_len);
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}
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}
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//remove edges between surviving tails and removed tails
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for(unsigned i=0; i<len; i++) {
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if (added_tails.contains(rule_content[i])) {
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continue;
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}
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for(unsigned ri=0; ri<rt_sz; ri++) {
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app_pair pair_key = get_key(rule_content[i], removed_tails[ri]);
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remove_rule_from_pair(pair_key, r, original_len);
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}
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}
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if (len==1) {
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return;
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}
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app * head = r->get_head();
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var_counter counter;
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counter.count_vars(head, 1);
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unsigned tail_size=r->get_tail_size();
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unsigned pos_tail_size=r->get_positive_tail_size();
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for(unsigned i=pos_tail_size; i<tail_size; i++) {
|
|
counter.count_vars(r->get_tail(i), 1);
|
|
}
|
|
for(unsigned i=0; i<len; i++) {
|
|
counter.count_vars(rule_content[i], 1);
|
|
}
|
|
|
|
//add edges that contain added tails
|
|
while(!added_tails.empty()) {
|
|
app * a_tail = added_tails.back(); //added tail
|
|
|
|
var_idx_set a_tail_vars = rm.collect_vars(a_tail);
|
|
counter.count_vars(a_tail, -1); //temporarily remove a_tail variables from counter
|
|
|
|
for(unsigned i=0; i<len; i++) {
|
|
app * o_tail = rule_content[i]; //other tail
|
|
if (added_tails.contains(o_tail)) {
|
|
//this avoids adding edges between new tails twice
|
|
continue;
|
|
}
|
|
|
|
counter.count_vars(o_tail, -1); //temporarily remove o_tail variables from counter
|
|
var_idx_set scope_vars = rm.collect_vars(o_tail);
|
|
scope_vars |= a_tail_vars;
|
|
var_idx_set non_local_vars;
|
|
counter.collect_positive(non_local_vars);
|
|
counter.count_vars(o_tail, 1); //restore o_tail variables in counter
|
|
set_intersection(non_local_vars, scope_vars);
|
|
|
|
register_pair(o_tail, a_tail, r, non_local_vars);
|
|
}
|
|
counter.count_vars(a_tail, 1); //restore t1 variables in counter
|
|
added_tails.pop_back();
|
|
}
|
|
}
|
|
|
|
void apply_binary_rule(rule * r, app_pair pair_key, app * t_new) {
|
|
app * t1 = pair_key.first;
|
|
app * t2 = pair_key.second;
|
|
ptr_vector<app> & rule_content = m_rules_content.find(r);
|
|
unsigned len = rule_content.size();
|
|
if (len==1) {
|
|
return;
|
|
}
|
|
|
|
func_decl * t1_pred = t1->get_decl();
|
|
func_decl * t2_pred = t2->get_decl();
|
|
ptr_vector<app> removed_tails;
|
|
ptr_vector<app> added_tails;
|
|
for(unsigned i1=0; i1<len; i1++) {
|
|
app * rt1 = rule_content[i1];
|
|
if (rt1->get_decl()!=t1_pred) {
|
|
continue;
|
|
}
|
|
unsigned i2start = (t1_pred==t2_pred) ? (i1+1) : 0;
|
|
for(unsigned i2=i2start; i2<len; i2++) {
|
|
app * rt2 = rule_content[i2];
|
|
if (i1==i2 || rt2->get_decl()!=t2_pred) {
|
|
continue;
|
|
}
|
|
if (get_key(rt1, rt2)!=pair_key) {
|
|
continue;
|
|
}
|
|
expr_ref_vector normalizer(m);
|
|
get_normalizer(rt1, rt2, normalizer);
|
|
expr_ref_vector denormalizer(m);
|
|
reverse_renaming(m, normalizer, denormalizer);
|
|
expr_ref new_transf(m);
|
|
m_var_subst(t_new, denormalizer.size(), denormalizer.c_ptr(), new_transf);
|
|
app * new_lit = to_app(new_transf);
|
|
|
|
m_pinned.push_back(new_lit);
|
|
rule_content[i1]=new_lit;
|
|
rule_content[i2]=rule_content.back();
|
|
rule_content.pop_back();
|
|
len--; //here the bound of both loops changes!!!
|
|
removed_tails.push_back(rt1);
|
|
removed_tails.push_back(rt2);
|
|
added_tails.push_back(new_lit);
|
|
//this exits the inner loop, the outer one continues in case there will
|
|
//be other matches
|
|
break;
|
|
}
|
|
}
|
|
SASSERT(!removed_tails.empty());
|
|
SASSERT(!added_tails.empty());
|
|
m_modified_rules = true;
|
|
replace_edges(r, removed_tails, added_tails, rule_content);
|
|
}
|
|
|
|
cost get_domain_size(func_decl * pred, unsigned arg_index) const {
|
|
relation_sort sort = pred->get_domain(arg_index);
|
|
return static_cast<cost>(m_context.get_sort_size_estimate(sort));
|
|
//unsigned sz;
|
|
//if (!m_context.get_sort_size(sort, sz)) {
|
|
// sz=UINT_MAX;
|
|
//}
|
|
//return static_cast<cost>(sz);
|
|
}
|
|
|
|
unsigned get_stratum(func_decl * pred) const {
|
|
return m_rs_aux_copy.get_predicate_strat(pred);
|
|
}
|
|
|
|
cost estimate_size(app * t) const {
|
|
func_decl * pred = t->get_decl();
|
|
unsigned n=pred->get_arity();
|
|
rel_context_base* rel = m_context.get_rel_context();
|
|
if (!rel) {
|
|
return cost(1);
|
|
}
|
|
relation_manager& rm = rel->get_rmanager();
|
|
if ( (m_context.saturation_was_run() && rm.try_get_relation(pred))
|
|
|| rm.is_saturated(pred)) {
|
|
SASSERT(rm.try_get_relation(pred)); //if it is saturated, it should exist
|
|
unsigned rel_size_int = rel->get_relation(pred).get_size_estimate_rows();
|
|
if (rel_size_int!=0) {
|
|
cost rel_size = static_cast<cost>(rel_size_int);
|
|
cost curr_size = rel_size;
|
|
for(unsigned i=0; i<n; i++) {
|
|
if (!is_var(t->get_arg(i))) {
|
|
curr_size /= get_domain_size(pred, i);
|
|
}
|
|
}
|
|
return curr_size;
|
|
}
|
|
}
|
|
cost res = 1;
|
|
for(unsigned i=0; i<n; i++) {
|
|
if (is_var(t->get_arg(i))) {
|
|
res *= get_domain_size(pred, i);
|
|
}
|
|
}
|
|
return res;
|
|
}
|
|
|
|
cost compute_cost(app * t1, app * t2, const var_idx_set & non_local_vars) const {
|
|
func_decl * t1_pred = t1->get_decl();
|
|
func_decl * t2_pred = t2->get_decl();
|
|
cost inters_size = 1;
|
|
variable_intersection vi(m_context.get_manager());
|
|
vi.populate(t1, t2);
|
|
unsigned n = vi.size();
|
|
// remove contributions from joined columns.
|
|
for(unsigned i=0; i<n; i++) {
|
|
unsigned arg_index1, arg_index2;
|
|
vi.get(i, arg_index1, arg_index2);
|
|
SASSERT(is_var(t1->get_arg(arg_index1)));
|
|
if (non_local_vars.contains(to_var(t1->get_arg(arg_index1))->get_idx())) {
|
|
inters_size *= get_domain_size(t1_pred, arg_index1);
|
|
}
|
|
//joined arguments must have the same domain
|
|
SASSERT(get_domain_size(t1_pred, arg_index1)==get_domain_size(t2_pred, arg_index2));
|
|
}
|
|
// remove contributions from projected columns.
|
|
for (unsigned i = 0; i < t1->get_num_args(); ++i) {
|
|
if (is_var(t1->get_arg(i)) &&
|
|
!non_local_vars.contains(to_var(t1->get_arg(i))->get_idx())) {
|
|
inters_size *= get_domain_size(t1_pred, i);
|
|
}
|
|
}
|
|
for (unsigned i = 0; i < t2->get_num_args(); ++i) {
|
|
if (is_var(t2->get_arg(i)) &&
|
|
!non_local_vars.contains(to_var(t2->get_arg(i))->get_idx())) {
|
|
inters_size *= get_domain_size(t2_pred, i);
|
|
}
|
|
}
|
|
|
|
cost res = estimate_size(t1)*estimate_size(t2)/ inters_size; // (inters_size*inters_size);
|
|
//cost res = -inters_size;
|
|
|
|
/*unsigned t1_strat = get_stratum(t1_pred);
|
|
SASSERT(t1_strat<=m_head_stratum);
|
|
if (t1_strat<m_head_stratum) {
|
|
unsigned t2_strat = get_stratum(t2_pred);
|
|
SASSERT(t2_strat<=m_head_stratum);
|
|
if (t2_strat<m_head_stratum) {
|
|
//the rule of this predicates would depend on predicates
|
|
//in lower stratum than the head, which is a good thing, since
|
|
//then the rule code will not need to appear in a loop
|
|
if (res>0) {
|
|
res /= 2;
|
|
}
|
|
else {
|
|
res *= 2;
|
|
}
|
|
}
|
|
}*/
|
|
|
|
TRACE("report_costs",
|
|
display_predicate(m_context, t1, tout);
|
|
display_predicate(m_context, t2, tout);
|
|
tout << res << "\n";);
|
|
return res;
|
|
}
|
|
|
|
|
|
bool pick_best_pair(app_pair & p) {
|
|
app_pair best;
|
|
bool found = false;
|
|
cost best_cost;
|
|
|
|
cost_map::iterator it = m_costs.begin();
|
|
cost_map::iterator end = m_costs.end();
|
|
for(; it!=end; ++it) {
|
|
app_pair key = it->m_key;
|
|
pair_info & inf = *it->m_value;
|
|
if (!inf.can_be_joined()) {
|
|
continue;
|
|
}
|
|
cost c = inf.get_cost();
|
|
if (!found || c<best_cost) {
|
|
found = true;
|
|
best_cost = c;
|
|
best = key;
|
|
}
|
|
}
|
|
if (!found) {
|
|
return false;
|
|
}
|
|
p=best;
|
|
return true;
|
|
}
|
|
|
|
|
|
public:
|
|
rule_set * run(rule_set const & source) {
|
|
|
|
unsigned num_rules = source.get_num_rules();
|
|
for (unsigned i = 0; i < num_rules; i++) {
|
|
register_rule(source.get_rule(i));
|
|
}
|
|
|
|
app_pair selected;
|
|
while(pick_best_pair(selected)) {
|
|
join_pair(selected);
|
|
}
|
|
|
|
if (!m_modified_rules) {
|
|
return 0;
|
|
}
|
|
rule_set * result = alloc(rule_set, m_context);
|
|
rule_pred_map::iterator rcit = m_rules_content.begin();
|
|
rule_pred_map::iterator rcend = m_rules_content.end();
|
|
for(; rcit!=rcend; ++rcit) {
|
|
rule * orig_r = rcit->m_key;
|
|
ptr_vector<app> content = rcit->m_value;
|
|
SASSERT(content.size()<=2);
|
|
if (content.size()==orig_r->get_positive_tail_size()) {
|
|
//rule did not change
|
|
result->add_rule(orig_r);
|
|
continue;
|
|
}
|
|
|
|
ptr_vector<app> tail(content);
|
|
svector<bool> negs(tail.size(), false);
|
|
unsigned or_len = orig_r->get_tail_size();
|
|
for(unsigned i=orig_r->get_positive_tail_size(); i<or_len; i++) {
|
|
tail.push_back(orig_r->get_tail(i));
|
|
negs.push_back(orig_r->is_neg_tail(i));
|
|
}
|
|
|
|
rule * new_rule = m_context.get_rule_manager().mk(orig_r->get_head(), tail.size(), tail.c_ptr(),
|
|
negs.c_ptr(), orig_r->name());
|
|
|
|
new_rule->set_accounting_parent_object(m_context, orig_r);
|
|
m_context.get_rule_manager().mk_rule_rewrite_proof(*orig_r, *new_rule);
|
|
result->add_rule(new_rule);
|
|
}
|
|
while (!m_introduced_rules.empty()) {
|
|
result->add_rule(m_introduced_rules.back());
|
|
m_context.get_rule_manager().mk_rule_asserted_proof(*m_introduced_rules.back());
|
|
m_introduced_rules.pop_back();
|
|
}
|
|
result->inherit_predicates(source);
|
|
return result;
|
|
}
|
|
};
|
|
|
|
rule_set * mk_simple_joins::operator()(rule_set const & source) {
|
|
rule_set rs_aux_copy(m_context);
|
|
rs_aux_copy.replace_rules(source);
|
|
if (!rs_aux_copy.is_closed()) {
|
|
rs_aux_copy.close();
|
|
}
|
|
|
|
join_planner planner(m_context, rs_aux_copy);
|
|
|
|
return planner.run(source);
|
|
}
|
|
|
|
|
|
};
|
|
|