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This commit is contained in:
Nikolaj Bjorner 2017-08-03 08:50:17 -07:00
commit ffaaa1ff34
14 changed files with 285 additions and 254 deletions

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@ -65,4 +65,7 @@ env:
# - os: osx
# osx_image: xcode 8.2
script:
- contrib/ci/scripts/travis_ci_entry_point.sh
# Use `travis_wait` to handle commands that don't show output for a long period of time.
# Currently this is the LTO build which can be very slow.
# Allow at most 45 minutes for the build.
- travis_wait 45 contrib/ci/scripts/travis_ci_entry_point.sh

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@ -25,155 +25,149 @@ Notes:
#include "api/api_model.h"
#include "api/api_ast_map.h"
#include "api/api_ast_vector.h"
#include "qe/qe_vartest.h"
#include "qe/qe_lite.h"
#include "muz/spacer/spacer_util.h"
#include "ast/expr_map.h"
extern "C"
{
Z3_ast Z3_API Z3_qe_model_project (Z3_context c,
Z3_model m,
unsigned num_bounds,
Z3_app const bound[],
Z3_ast body)
{
Z3_TRY;
LOG_Z3_qe_model_project (c, m, num_bounds, bound, body);
RESET_ERROR_CODE();
app_ref_vector vars(mk_c(c)->m ());
for (unsigned i = 0; i < num_bounds; ++i)
{
app *a = to_app (bound [i]);
if (a->get_kind () != AST_APP)
{
SET_ERROR_CODE (Z3_INVALID_ARG);
RETURN_Z3(0);
}
vars.push_back (a);
static bool to_apps(unsigned n, Z3_app const es[], app_ref_vector& result) {
for (unsigned i = 0; i < n; ++i) {
if (!is_app(to_app(es[i]))) {
return false;
}
result.push_back (to_app (es [i]));
}
return true;
}
expr_ref result (mk_c(c)->m ());
result = to_expr (body);
model_ref model (to_model_ref (m));
spacer::qe_project (mk_c(c)->m (), vars, result, model);
mk_c(c)->save_ast_trail (result.get ());
return of_expr (result.get ());
Z3_CATCH_RETURN(0);
}
Z3_ast Z3_API Z3_qe_model_project_skolem (Z3_context c,
Z3_ast Z3_API Z3_qe_model_project (Z3_context c,
Z3_model m,
unsigned num_bounds,
Z3_app const bound[],
Z3_ast body,
Z3_ast_map map)
Z3_ast body)
{
Z3_TRY;
LOG_Z3_qe_model_project_skolem (c, m, num_bounds, bound, body, map);
RESET_ERROR_CODE();
ast_manager& man = mk_c(c)->m ();
app_ref_vector vars(man);
for (unsigned i = 0; i < num_bounds; ++i)
{
app *a = to_app (bound [i]);
if (a->get_kind () != AST_APP)
{
SET_ERROR_CODE (Z3_INVALID_ARG);
RETURN_Z3(0);
Z3_TRY;
LOG_Z3_qe_model_project (c, m, num_bounds, bound, body);
RESET_ERROR_CODE();
app_ref_vector vars(mk_c(c)->m ());
if (!to_apps(num_bounds, bound, vars)) {
SET_ERROR_CODE (Z3_INVALID_ARG);
RETURN_Z3(0);
}
vars.push_back (a);
}
expr_ref result (mk_c(c)->m ());
result = to_expr (body);
model_ref model (to_model_ref (m));
expr_map emap (man);
expr_ref result (mk_c(c)->m ());
result = to_expr (body);
model_ref model (to_model_ref (m));
spacer::qe_project (mk_c(c)->m (), vars, result, model);
mk_c(c)->save_ast_trail (result.get ());
spacer::qe_project (mk_c(c)->m (), vars, result, model, emap);
mk_c(c)->save_ast_trail (result.get ());
obj_map<ast, ast*> &map_z3 = to_ast_map_ref(map);
for (expr_map::iterator it = emap.begin(), end = emap.end(); it != end; ++it){
man.inc_ref(&(it->get_key()));
man.inc_ref(it->get_value());
map_z3.insert(&(it->get_key()), it->get_value());
}
return of_expr (result.get ());
Z3_CATCH_RETURN(0);
return of_expr (result.get ());
Z3_CATCH_RETURN(0);
}
Z3_ast Z3_API Z3_model_extrapolate (Z3_context c,
Z3_model m,
Z3_ast fml)
{
Z3_TRY;
LOG_Z3_model_extrapolate (c, m, fml);
RESET_ERROR_CODE();
model_ref model (to_model_ref (m));
expr_ref_vector facts (mk_c(c)->m ());
facts.push_back (to_expr (fml));
flatten_and (facts);
spacer::model_evaluator_util mev (mk_c(c)->m());
mev.set_model (*model);
expr_ref_vector lits (mk_c(c)->m());
spacer::compute_implicant_literals (mev, facts, lits);
expr_ref result (mk_c(c)->m ());
result = mk_and (lits);
mk_c(c)->save_ast_trail (result.get ());
return of_expr (result.get ());
Z3_CATCH_RETURN(0);
}
Z3_ast Z3_API Z3_qe_lite (Z3_context c, Z3_ast_vector vars, Z3_ast body)
{
Z3_TRY;
LOG_Z3_qe_lite (c, vars, body);
RESET_ERROR_CODE();
ast_ref_vector &vVars = to_ast_vector_ref (vars);
app_ref_vector vApps (mk_c(c)->m());
for (unsigned i = 0; i < vVars.size (); ++i)
Z3_ast Z3_API Z3_qe_model_project_skolem (Z3_context c,
Z3_model m,
unsigned num_bounds,
Z3_app const bound[],
Z3_ast body,
Z3_ast_map map)
{
app *a = to_app (vVars.get (i));
if (a->get_kind () != AST_APP)
{
SET_ERROR_CODE (Z3_INVALID_ARG);
RETURN_Z3(0);
}
vApps.push_back (a);
Z3_TRY;
LOG_Z3_qe_model_project_skolem (c, m, num_bounds, bound, body, map);
RESET_ERROR_CODE();
ast_manager& man = mk_c(c)->m ();
app_ref_vector vars(man);
if (!to_apps(num_bounds, bound, vars)) {
RETURN_Z3(0);
}
expr_ref result (mk_c(c)->m ());
result = to_expr (body);
model_ref model (to_model_ref (m));
expr_map emap (man);
spacer::qe_project (mk_c(c)->m (), vars, result, model, emap);
mk_c(c)->save_ast_trail (result.get ());
obj_map<ast, ast*> &map_z3 = to_ast_map_ref(map);
for (expr_map::iterator it = emap.begin(), end = emap.end(); it != end; ++it){
man.inc_ref(&(it->get_key()));
man.inc_ref(it->get_value());
map_z3.insert(&(it->get_key()), it->get_value());
}
return of_expr (result.get ());
Z3_CATCH_RETURN(0);
}
expr_ref result (mk_c(c)->m ());
result = to_expr (body);
params_ref p;
qe_lite qe (mk_c(c)->m (), p);
qe (vApps, result);
// -- copy back variables that were not eliminated
if (vApps.size () < vVars.size ())
Z3_ast Z3_API Z3_model_extrapolate (Z3_context c,
Z3_model m,
Z3_ast fml)
{
vVars.reset ();
for (unsigned i = 0; i < vApps.size (); ++i)
vVars.push_back (vApps.get (i));
Z3_TRY;
LOG_Z3_model_extrapolate (c, m, fml);
RESET_ERROR_CODE();
model_ref model (to_model_ref (m));
expr_ref_vector facts (mk_c(c)->m ());
facts.push_back (to_expr (fml));
flatten_and (facts);
spacer::model_evaluator_util mev (mk_c(c)->m());
mev.set_model (*model);
expr_ref_vector lits (mk_c(c)->m());
spacer::compute_implicant_literals (mev, facts, lits);
expr_ref result (mk_c(c)->m ());
result = mk_and (lits);
mk_c(c)->save_ast_trail (result.get ());
return of_expr (result.get ());
Z3_CATCH_RETURN(0);
}
mk_c(c)->save_ast_trail (result.get ());
return of_expr (result);
Z3_CATCH_RETURN(0);
}
Z3_ast Z3_API Z3_qe_lite (Z3_context c, Z3_ast_vector vars, Z3_ast body)
{
Z3_TRY;
LOG_Z3_qe_lite (c, vars, body);
RESET_ERROR_CODE();
ast_ref_vector &vVars = to_ast_vector_ref (vars);
app_ref_vector vApps (mk_c(c)->m());
for (unsigned i = 0; i < vVars.size (); ++i) {
app *a = to_app (vVars.get (i));
if (a->get_kind () != AST_APP) {
SET_ERROR_CODE (Z3_INVALID_ARG);
RETURN_Z3(0);
}
vApps.push_back (a);
}
expr_ref result (mk_c(c)->m ());
result = to_expr (body);
params_ref p;
qe_lite qe (mk_c(c)->m (), p);
qe (vApps, result);
// -- copy back variables that were not eliminated
if (vApps.size () < vVars.size ()) {
vVars.reset ();
for (app* v : vApps) {
vVars.push_back (v);
}
}
mk_c(c)->save_ast_trail (result.get ());
return of_expr (result);
Z3_CATCH_RETURN(0);
}
}

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@ -23,6 +23,7 @@ z3_add_component(ast
expr_map.cpp
expr_stat.cpp
expr_substitution.cpp
factor_equivs.cpp
for_each_ast.cpp
for_each_expr.cpp
format.cpp

109
src/ast/factor_equivs.cpp Normal file
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@ -0,0 +1,109 @@
/*++
Copyright (c) 2017 Arie Gurfinkel
Module Name:
factor_equivs.cpp
Abstract:
Factor equivalence classes out of an expression.
"Equivalence class structure" for objs. Uses a union_find structure internally.
Operations are :
-Declare a new equivalence class with a single element
-Merge two equivalence classes
-Retrieve whether two elements are in the same equivalence class
-Iterate on all the elements of the equivalence class of a given element
-Iterate on all equivalence classes (and then within them)
Author:
Julien Braine
Arie Gurfinkel
Revision History:
*/
#include "ast/factor_equivs.h"
#include "ast/arith_decl_plugin.h"
/**
Factors input vector v into equivalence classes and the rest
*/
void factor_eqs(expr_ref_vector &v, expr_equiv_class &equiv) {
ast_manager &m = v.get_manager();
arith_util arith(m);
expr *e1 = 0, *e2 = 0;
flatten_and(v);
unsigned j = 0;
for (unsigned i = 0; i < v.size(); ++i) {
if (m.is_eq(v.get(i), e1, e2)) {
if (arith.is_zero(e1)) {
std::swap(e1, e2);
}
// y + -1*x == 0
expr* a0 = 0, *a1 = 0, *x = 0;
if (arith.is_zero(e2) && arith.is_add(e1, a0, a1)) {
if (arith.is_times_minus_one(a1, x)) {
e1 = a0;
e2 = x;
}
else if (arith.is_times_minus_one(a0, x)) {
e1 = a1;
e2 = x;
}
}
equiv.merge(e1, e2);
}
else {
if (j < i) {
v[j] = v.get(i);
}
j++;
}
}
v.shrink(j);
}
/**
* converts equivalence classes to equalities
*/
void equiv_to_expr(expr_equiv_class &equiv, expr_ref_vector &out) {
ast_manager &m = out.get_manager();
for (auto eq_class : equiv) {
expr *rep = nullptr;
for (expr *elem : eq_class) {
if (!m.is_value(elem)) {
rep = elem;
break;
}
}
SASSERT(rep);
for (expr *elem : eq_class) {
if (rep != elem) {
out.push_back (m.mk_eq (rep, elem));
}
}
}
}
/**
* expands equivalence classes to all derivable equalities
*/
bool equiv_to_expr_full(expr_equiv_class &equiv, expr_ref_vector &out) {
ast_manager &m = out.get_manager();
bool dirty = false;
for (auto eq_class : equiv) {
for (auto a = eq_class.begin(), end = eq_class.end(); a != end; ++a) {
expr_equiv_class::iterator b(a);
for (++b; b != end; ++b) {
out.push_back(m.mk_eq(*a, *b));
dirty = true;
}
}
}
return dirty;
}

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@ -3,9 +3,11 @@ Copyright (c) 2017 Arie Gurfinkel
Module Name:
obj_equiv_class.h
factor_equivs.h
Abstract:
Factor equivalence classes out of an expression.
"Equivalence class structure" for objs. Uses a union_find structure internally.
Operations are :
-Declare a new equivalence class with a single element
@ -17,19 +19,19 @@ Abstract:
Author:
Julien Braine
Arie Gurfinkel
Revision History:
*/
#ifndef OBJ_EQUIV_CLASS_H_
#define OBJ_EQUIV_CLASS_H_
#ifndef FACTOR_EQUIVS_H_
#define FACTOR_EQUIVS_H_
#include "util/union_find.h"
#include "ast/ast_util.h"
namespace spacer {
//All functions naturally add their parameters to the union_find class
///All functions naturally add their parameters to the union_find class
template<typename OBJ, typename Manager>
class obj_equiv_class {
basic_union_find m_uf;
@ -164,87 +166,18 @@ typedef obj_equiv_class<expr, ast_manager> expr_equiv_class;
/**
Factors input vector v into equivalence classes and the rest
* Factors input vector v into equivalence classes and the rest
*/
inline void factor_eqs(expr_ref_vector &v, expr_equiv_class &equiv) {
ast_manager &m = v.get_manager();
arith_util arith(m);
expr *e1, *e2;
flatten_and(v);
unsigned j = 0;
for (unsigned i = 0; i < v.size(); ++i) {
if (m.is_eq(v.get(i), e1, e2)) {
if (arith.is_zero(e1)) {
expr* t;
t = e1; e1 = e2; e2 = t;
}
// y + -1*x == 0
if (arith.is_zero(e2) && arith.is_add(e1) &&
to_app(e1)->get_num_args() == 2) {
expr *a0, *a1, *x;
a0 = to_app(e1)->get_arg(0);
a1 = to_app(e1)->get_arg(1);
if (arith.is_times_minus_one(a1, x)) {
e1 = a0;
e2 = x;
}
else if (arith.is_times_minus_one(a0, x)) {
e1 = a1;
e2 = x;
}
}
equiv.merge(e1, e2);
}
else {
if (j < i) {v[j] = v.get(i);}
j++;
}
}
v.shrink(j);
}
void factor_eqs(expr_ref_vector &v, expr_equiv_class &equiv);
/**
* converts equivalence classes to equalities
*/
inline void equiv_to_expr(expr_equiv_class &equiv, expr_ref_vector &out) {
ast_manager &m = out.get_manager();
for (auto eq_class : equiv) {
expr *rep = nullptr;
for (expr *elem : eq_class) {
if (!m.is_value (elem)) {
rep = elem;
break;
}
}
SASSERT(rep);
for (expr *elem : eq_class) {
if (rep != elem) {out.push_back (m.mk_eq (rep, elem));}
}
}
}
void equiv_to_expr(expr_equiv_class &equiv, expr_ref_vector &out);
/**
* expands equivalence classes to all derivable equalities
*/
inline bool equiv_to_expr_full(expr_equiv_class &equiv, expr_ref_vector &out) {
ast_manager &m = out.get_manager();
bool dirty = false;
for (auto eq_class : equiv) {
for (auto a = eq_class.begin(), end = eq_class.end(); a != end; ++a) {
expr_equiv_class::iterator b(a);
for (++b; b != end; ++b) {
out.push_back(m.mk_eq(*a, *b));
dirty = true;
}
}
}
return dirty;
}
bool equiv_to_expr_full(expr_equiv_class &equiv, expr_ref_vector &out);
}
#endif

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@ -50,7 +50,6 @@ Notes:
#include "util/luby.h"
#include "ast/rewriter/expr_safe_replace.h"
#include "ast/expr_abstract.h"
#include "muz/spacer/obj_equiv_class.h"
namespace spacer {
@ -1123,7 +1122,7 @@ lemma::lemma(pob_ref const &p) :
m_pob(p), m_new_pob(m_pob) {SASSERT(m_pob);}
lemma::lemma(pob_ref const &p, expr_ref_vector &cube, unsigned lvl) :
m_ref_count(0),
m_ref_count(0),
m(p->get_ast_manager()),
m_body(m), m_cube(m),
m_bindings(m), m_lvl(p->level()),

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@ -24,7 +24,7 @@ Revision History:
#include "ast/expr_abstract.h"
#include "ast/rewriter/var_subst.h"
#include "ast/for_each_expr.h"
#include "muz/spacer/obj_equiv_class.h"
#include "ast/factor_equivs.h"
namespace spacer {

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@ -34,7 +34,7 @@
#include "util/luby.h"
#include "ast/rewriter/expr_safe_replace.h"
#include "ast/expr_abstract.h"
#include "muz/spacer/obj_equiv_class.h"
#include "ast/factor_equivs.h"
namespace spacer {

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@ -63,7 +63,7 @@ Notes:
#include "tactic/arith/propagate_ineqs_tactic.h"
#include "tactic/arith/arith_bounds_tactic.h"
#include "muz/spacer/obj_equiv_class.h"
#include "ast/factor_equivs.h"
namespace spacer {

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@ -22,11 +22,7 @@ Revision History:
#include "muz/base/dl_context.h"
#include "muz/base/fixedpoint_params.hpp"
#include "muz/transforms/dl_mk_array_eq_rewrite.h"
#include "../spacer/obj_equiv_class.h"
// NSB code review: avoid dependency on spacer inside this directory.
// The python build system will rightfully complain if you include
// "muz/spacer/obj_equiv_class.h".
#include "ast/factor_equivs.h"
namespace datalog {
@ -65,7 +61,7 @@ namespace datalog {
new_tail.push_back(r.get_tail(i));
}
spacer::expr_equiv_class array_eq_classes(m);
expr_equiv_class array_eq_classes(m);
for(unsigned i = nb_predicates; i < tail_size; i++) {
expr* cond = r.get_tail(i);
expr* e1, *e2;

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@ -11,16 +11,14 @@ Author:
Julien Braine
Revision History:
Revision History:
--*/
#ifndef DL_MK_ARRAY_EQ_REWRITE_H_
#define DL_MK_ARRAY_EQ_REWRITE_H_
#include "muz/base/dl_rule_transformer.h"
#include "../spacer/obj_equiv_class.h"
namespace datalog {
@ -30,7 +28,7 @@ namespace datalog {
ast_manager& m;
context& m_ctx;
array_util m_a;
//Rule set context
const rule_set* m_src_set;
rule_set* m_dst;
@ -51,4 +49,3 @@ namespace datalog {
};
#endif /* DL_MK_ARRAY_EQ_REWRITE_H_ */

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@ -24,7 +24,6 @@ Revision History:
#include "ast/rewriter/expr_safe_replace.h"
#include "ast/expr_abstract.h"
#include "muz/base/fixedpoint_params.hpp"
#include "../spacer/obj_equiv_class.h"
namespace datalog {
@ -244,7 +243,7 @@ namespace datalog {
expr_ref_vector mk_array_instantiation::retrieve_all_selects(expr*array)
{
expr_ref_vector all_selects(m);
for(spacer::expr_equiv_class::iterator it = eq_classes.begin(array);
for(expr_equiv_class::iterator it = eq_classes.begin(array);
it != eq_classes.end(array); ++it)
{
selects.insert_if_not_there(*it, ptr_vector<expr>());

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@ -70,8 +70,8 @@ Revision History:
#define DL_MK_ARRAY_INSTANTIATION_H_
#include "ast/factor_equivs.h"
#include "muz/base/dl_rule_transformer.h"
#include "../spacer/obj_equiv_class.h"
namespace datalog {
@ -89,7 +89,7 @@ namespace datalog {
//Rule context
obj_map<expr, ptr_vector<expr> > selects;
spacer::expr_equiv_class eq_classes;
expr_equiv_class eq_classes;
unsigned cnt;//Index for new variables
obj_map<expr, var*> done_selects;
expr_ref_vector ownership;

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@ -22,6 +22,7 @@ Revision History:
#include "util/obj_hashtable.h"
#include "util/region.h"
#include "util/obj_ref.h"
#include "util/vector.h"
template<typename Ctx>
class trail {
@ -35,16 +36,16 @@ template<typename Ctx, typename T>
class value_trail : public trail<Ctx> {
T & m_value;
T m_old_value;
public:
value_trail(T & value):
m_value(value),
m_old_value(value) {
}
virtual ~value_trail() {
}
virtual void undo(Ctx & ctx) {
m_value = m_old_value;
}
@ -57,10 +58,10 @@ public:
reset_flag_trail(bool & value):
m_value(value) {
}
virtual ~reset_flag_trail() {
}
virtual void undo(Ctx & ctx) {
m_value = false;
}
@ -74,7 +75,7 @@ public:
m_ptr(ptr) {
SASSERT(m_ptr == 0);
}
virtual void undo(Ctx & ctx) {
m_ptr = 0;
}
@ -98,8 +99,8 @@ public:
virtual void undo(Ctx & ctx) {
m_vector.shrink(m_old_size);
}
};
};
template<typename Ctx, typename T, bool CallDestructors=true>
class vector_value_trail : public trail<Ctx> {
vector<T, CallDestructors> & m_vector;
@ -111,10 +112,10 @@ public:
m_idx(idx),
m_old_value(v[idx]) {
}
virtual ~vector_value_trail() {
}
virtual void undo(Ctx & ctx) {
m_vector[m_idx] = m_old_value;
}
@ -150,7 +151,7 @@ public:
push_back_vector(V & v):
m_vector(v) {
}
virtual void undo(Ctx & ctx) {
m_vector.pop_back();
}
@ -165,15 +166,15 @@ public:
m_vector(v),
m_idx(idx) {
}
virtual ~set_vector_idx_trail() {
}
virtual void undo(Ctx & ctx) {
m_vector[m_idx] = 0;
}
};
template<typename Ctx, typename T, bool CallDestructors=true>
class pop_back_trail : public trail<Ctx> {
vector<T, CallDestructors> & m_vector;
@ -183,7 +184,7 @@ public:
m_vector(v),
m_value(m_vector.back()) {
}
virtual void undo(Ctx & ctx) {
m_vector.push_back(m_value);
}
@ -201,7 +202,7 @@ public:
m_index(index),
m_value(m_vector[index].back()) {
}
virtual void undo(Ctx & ctx) {
m_vector[m_index].push_back(m_value);
}
@ -216,7 +217,7 @@ public:
push_back_trail(vector<T, CallDestructors> & v):
m_vector(v) {
}
virtual void undo(Ctx & ctx) {
m_vector.pop_back();
}
@ -228,11 +229,11 @@ class push_back2_trail : public trail<Ctx> {
vector_t & m_vector;
unsigned m_index;
public:
push_back2_trail(vector_t & v, unsigned index) :
push_back2_trail(vector_t & v, unsigned index) :
m_vector(v),
m_index(index) {
}
virtual void undo(Ctx & ctx) {
m_vector[m_index].pop_back();
}
@ -249,12 +250,12 @@ public:
SASSERT(m_vector[m_idx] == false);
m_vector[m_idx] = true;
}
virtual void undo(Ctx & ctx) {
m_vector[m_idx] = false;
}
};
template<typename Ctx, typename T>
class new_obj_trail : public trail<Ctx> {
T * m_obj;
@ -262,7 +263,7 @@ public:
new_obj_trail(T * obj):
m_obj(obj) {
}
virtual void undo(Ctx & ctx) {
dealloc(m_obj);
}
@ -275,7 +276,7 @@ public:
obj_ref_trail(obj_ref<T,M>& obj):
m_obj(obj) {
}
virtual void undo(Ctx & ctx) {
m_obj.reset();
}
@ -300,7 +301,7 @@ class remove_obj_trail : public trail<Ctx> {
public:
remove_obj_trail(obj_hashtable<T>& t, T* o) : m_table(t), m_obj(o) {}
virtual ~remove_obj_trail() {}
virtual void undo(Ctx & ctx) { m_table.insert(m_obj); }
virtual void undo(Ctx & ctx) { m_table.insert(m_obj); }
};
@ -326,13 +327,13 @@ public:
trail_stack(Ctx & c):m_ctx(c) {}
~trail_stack() {}
region & get_region() { return m_region; }
void reset() {
pop_scope(m_scopes.size());
void reset() {
pop_scope(m_scopes.size());
// Undo trail objects stored at lvl 0 (avoid memory leaks if lvl 0 contains new_obj_trail objects).
undo_trail_stack(m_ctx, m_trail_stack, 0);
undo_trail_stack(m_ctx, m_trail_stack, 0);
}
void push_ptr(trail<Ctx> * t) { m_trail_stack.push_back(t); }
@ -357,4 +358,3 @@ public:
};
#endif /* TRAIL_H_ */