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add array selects to basic ackerman reduction improves performance significantly for #2525 as it now uses the SAT solver core instead of SMT core

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Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>
This commit is contained in:
Nikolaj Bjorner 2019-09-01 12:17:10 -07:00
parent 7823117776
commit 000e485794
25 changed files with 706 additions and 572 deletions
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109
src/ackermannization/ackr_helper.h
View file

@ -18,45 +18,86 @@
#define ACKR_HELPER_H_
#include "ast/bv_decl_plugin.h"
#include "ast/array_decl_plugin.h"
class ackr_helper {
public:
typedef obj_hashtable<app> app_set;
typedef obj_map<func_decl, app_set*> fun2terms_map;
public:
typedef obj_hashtable<app> app_set;
typedef obj_map<func_decl, app_set*> fun2terms_map;
typedef obj_map<app, app_set*> sel2terms_map;
ackr_helper(ast_manager& m) : m_bvutil(m), m_autil(m) {}
/**
\brief Determines if a given function should be Ackermannized.
This includes all uninterpreted functions but also "special" functions, e.g. OP_BSMOD0,
which are not marked as uninterpreted but effectively are.
*/
inline bool is_uninterp_fn(app const * a) const {
if (is_uninterp(a))
return true;
else {
decl_plugin * p = m_bvutil.get_manager().get_plugin(a->get_family_id());
return p->is_considered_uninterpreted(a->get_decl());
}
}
ackr_helper(ast_manager& m) : m_bvutil(m) {}
/**
\brief determines if a term is a candidate select for Ackerman reduction
*/
inline bool is_select(app* a) {
return m_autil.is_select(a) && is_uninterp_const(a->get_arg(0));
}
/**
\brief Determines if a given function should be Ackermannized.
This includes all uninterpreted functions but also "special" functions, e.g. OP_BSMOD0,
which are not marked as uninterpreted but effectively are.
*/
inline bool should_ackermannize(app const * a) const {
if (is_uninterp(a))
return true;
else {
decl_plugin * p = m_bvutil.get_manager().get_plugin(a->get_family_id());
return p->is_considered_uninterpreted(a->get_decl());
void mark_non_select(app* a, expr_mark& non_select) {
if (m_autil.is_select(a)) {
bool first = true;
for (expr* arg : *a) {
if (first)
first = false;
else
non_select.mark(arg, true);
}
}
inline bv_util& bvutil() { return m_bvutil; }
/**
\brief Calculates an upper bound for congruence lemmas given a map of function of occurrences.
*/
static double calculate_lemma_bound(fun2terms_map& occurrences);
/** \brief Calculate n choose 2. **/
inline static unsigned n_choose_2(unsigned n) { return n & 1 ? (n * (n >> 1)) : (n >> 1) * (n - 1); }
/** \brief Calculate n choose 2 guarded for overflow. Returns infinity if unsafe. **/
inline static double n_choose_2_chk(unsigned n) {
SASSERT(std::numeric_limits<unsigned>().max() & 32);
return n & (1 << 16) ? std::numeric_limits<double>().infinity() : n_choose_2(n);
else {
for (expr* arg : *a) {
non_select.mark(arg, true);
}
}
private:
bv_util m_bvutil;
}
void prune_non_select(obj_map<app, app_set*> & sels, expr_mark& non_select) {
ptr_vector<app> nons;
for (auto& kv : sels) {
if (non_select.is_marked(kv.m_key)) {
nons.push_back(kv.m_key);
dealloc(kv.m_value);
}
}
for (app* s : nons) {
sels.erase(s);
}
}
inline bv_util& bvutil() { return m_bvutil; }
/**
\brief Calculates an upper bound for congruence lemmas given a map of function of occurrences.
*/
static double calculate_lemma_bound(fun2terms_map const& occs1, sel2terms_map const& occs2);
/** \brief Calculate n choose 2. **/
inline static unsigned n_choose_2(unsigned n) { return n & 1 ? (n * (n >> 1)) : (n >> 1) * (n - 1); }
/** \brief Calculate n choose 2 guarded for overflow. Returns infinity if unsafe. **/
inline static double n_choose_2_chk(unsigned n) {
SASSERT(std::numeric_limits<unsigned>().max() & 32);
return n & (1 << 16) ? std::numeric_limits<double>().infinity() : n_choose_2(n);
}
private:
bv_util m_bvutil;
array_util m_autil;
};
#endif /* ACKR_HELPER_H_6475 */
#endif /* ACKR_HELPER_H_ */