alarsyo/spot
1
0
Fork 0
Code Issues Pull requests Projects Releases Wiki Activity

simplify: fix 3 incorrect simplification rules

Browse source 
* src/ltlvisit/simplify.cc: Remove two incorrect rules, and
partially disable another one.
* doc/tl/tl.tex: Reflect the change.
* src/ltltest/reduccmp.test: Likewise.
* src/ltltest/equals.cc: Add safety checks to catch such errors in the
future.
* NEWS: Mention the bug.
This commit is contained in:
Alexandre Duret-Lutz 2014-05-13 16:59:51 +02:00
parent 34fd27a381
commit 48471b5114
5 changed files with 61 additions and 123 deletions
Download patch file Download diff file Expand all files Collapse all files

3
NEWS
View file

@ -14,6 +14,9 @@ New in spot 1.2.3a (not yet released)
- "ltl2tgta --ta" could crash in certain conditions due to the
introduction of a simulation-based reduction after
degeneralization.
- Fix three incorrect simplifications rules, all related to the
factorization of Boolean subformulas in operands of the
non-length-matching "&" SERE operator.
New in spot 1.2.3 (2014-02-11)

10
doc/tl/tl.tex
View file

@ -1460,13 +1460,11 @@ SERE.
\0 &\text{else}\\
\end{cases}\\
\sere{b_1\CONCAT r_1}\ANDALT\sere{b_2\CONCAT r_2} &\equiv \sere{b_1\ANDALT b_2}\CONCAT\sere{r_1\ANDALT r_2} &
\sere{b_1\CONCAT r_1}\AND \sere{b_2\CONCAT r_2} &\equiv \sere{b_1\ANDALT b_2}\CONCAT\sere{r_1\AND r_2} \\
\sere{r_1\CONCAT b_1}\ANDALT\sere{r_2\CONCAT b_2} &\equiv \sere{r_1\ANDALT r_2}\CONCAT\sere{b_1\ANDALT b_2} \\
\sere{b_1\FUSION r_1}\ANDALT\sere{b_2\FUSION r_2} &\equiv \sere{b_1\ANDALT b_2}\FUSION\sere{r_1\ANDALT r_2} &
\sere{b_1\FUSION r_1}\AND \sere{b_2\FUSION r_2} &\equiv \sere{b_1\ANDALT b_2}\FUSION\sere{r_1\AND r_2} \\
\sere{r_1\CONCAT b_1}\ANDALT\sere{r_2\CONCAT b_2} &\equiv \sere{r_1\ANDALT r_2}\CONCAT\sere{b_1\ANDALT b_2} &
\sere{r_1\CONCAT b_1}\AND \sere{r_2\CONCAT b_2} &\equiv \sere{r_1\ANDALT r_2}\CONCAT\sere{b_1\AND b_2} \\
\sere{r_1\FUSION b_1}\ANDALT\sere{r_2\FUSION b_2} &\equiv \sere{r_1\ANDALT r_2}\FUSION\sere{b_1\ANDALT b_2} &
\sere{r_1\FUSION b_1}\AND \sere{r_2\FUSION b_2} &\equiv \sere{r_1\ANDALT r_2}\FUSION\sere{b_1\AND b_2} \\
\sere{r_1\FUSION b_1}\ANDALT\sere{r_2\FUSION b_2} &\equiv \sere{r_1\ANDALT r_2}\FUSION\sere{b_1\ANDALT b_2} \\
\sere{b_1\CONCAT r_1}\AND \sere{b_2\CONCAT r_2} &\equiv \sere{b_1\ANDALT b_2}\CONCAT\sere{r_1\AND r_2} \\
\sere{b_1\FUSION r_1}\AND \sere{b_2\FUSION r_2} &\equiv \sere{b_1\ANDALT b_2}\FUSION\sere{r_1\AND r_2} \mathrlap{\quad\text{if~}\varepsilon\nVDash r_1\land\varepsilon\nVDash r_2}\\
\end{align*}
Starred subformul\ae{} are rewritten in Star Normal

39
src/ltltest/equals.cc
View file

@ -1,6 +1,6 @@
// -*- coding: utf-8 -*-
// Copyright (C) 2008, 2009, 2010, 2011, 2012 Laboratoire de Recherche
// et Développement de l'Epita (LRDE).
// Copyright (C) 2008, 2009, 2010, 2011, 2012, 2014 Laboratoire de
// Recherche et Développement de l'Epita (LRDE).
// Copyright (C) 2003, 2004, 2006 Laboratoire d'Informatique de
// Paris 6 (LIP6), département Systèmes Répartis Coopératifs (SRC),
// Université Pierre et Marie Curie.
@ -68,7 +68,7 @@ main(int argc, char** argv)
if (spot::ltl::format_parse_errors(std::cerr, argv[2], p2))
return 2;
int exit_code;
int exit_code = 0;
{
#if defined LUNABBREV || defined TUNABBREV || defined NENOFORM || defined WM
@ -112,6 +112,14 @@ main(int argc, char** argv)
const spot::ltl::formula* tmp;
tmp = f1;
f1 = simp.simplify(f1);
if (!simp.are_equivalent(f1, tmp))
{
std::cerr << "Source and simplified formulae are not equivalent!\n";
std::cerr << "Simplified: " << spot::ltl::to_string(f1) << "\n";
exit_code = 1;
}
tmp->destroy();
}
spot::ltl::dump(std::cout, f1);
@ -124,6 +132,14 @@ main(int argc, char** argv)
const spot::ltl::formula* tmp;
tmp = f1;
f1 = simp.simplify(f1);
if (!simp.are_equivalent(f1, tmp))
{
std::cerr << "Source and simplified formulae are not equivalent!\n";
std::cerr << "Simplified: " << spot::ltl::to_string(f1) << "\n";
exit_code = 1;
}
tmp->destroy();
}
spot::ltl::dump(std::cout, f1);
@ -136,13 +152,21 @@ main(int argc, char** argv)
const spot::ltl::formula* tmp;
tmp = f1;
f1 = simp.simplify(f1);
if (!simp.are_equivalent(f1, tmp))
{
std::cerr << "Source and simplified formulae are not equivalent!\n";
std::cerr << "Simplified: " << spot::ltl::to_string(f1) << "\n";
exit_code = 1;
}
tmp->destroy();
}
spot::ltl::dump(std::cout, f1);
std::cout << std::endl;
#endif
exit_code = f1 != f2;
exit_code |= f1 != f2;
#if (!defined(REDUC) && !defined(REDUC_TAU) && !defined(REDUC_TAUSTR))
spot::ltl::ltl_simplifier simp;
@ -150,8 +174,11 @@ main(int argc, char** argv)
if (!simp.are_equivalent(f1, f2))
{
std::cerr << "Source and destination formulae are not equivalent!"
<< std::endl;
#if (!defined(REDUC) && !defined(REDUC_TAU) && !defined(REDUC_TAUSTR))
std::cerr << "Source and destination formulae are not equivalent!\n";
#else
std::cerr << "Simpl. and destination formulae are not equivalent!\n";
#endif
exit_code = 1;
}

11
src/ltltest/reduccmp.test
View file

@ -1,7 +1,7 @@
#! /bin/sh
# -*- coding: utf-8 -*-
# Copyright (C) 2009, 2010, 2011, 2012, 2013 Laboratoire de Recherche
# et Developpement de l'Epita (LRDE).
# Copyright (C) 2009, 2010, 2011, 2012, 2013, 2014 Laboratoire de
# Recherche et Developpement de l'Epita (LRDE).
# Copyright (C) 2004, 2006 Laboratoire d'Informatique de Paris 6 (LIP6),
# département Systèmes Répartis Coopératifs (SRC), Université Pierre
# et Marie Curie.
@ -317,9 +317,10 @@ for x in ../reduccmp ../reductaustr; do
run 0 $x '{{a;b*;c}&&{d;e*}&&{f*;g}&&{h*}}' \
'{{f*;g}&&{h*}&&{{a&&d};{e* && {b*;c}}}}'
run 0 $x '{{{b1;r1*}&{b2;r2*}};c}' 'b1&b2&X{{r1*&r2*};c}'
run 0 $x '{{b1:r1*}&{b2:r2*}}' '{{b1&&b2}:{r1*&r2*}}'
run 0 $x '{{r1*;b1}&{r2*;b2}}' '{{r1*&r2*};{b1&&b2}}'
run 0 $x '{{r1*:b1}&{r2*:b2}}' '{{r1*&r2*}:{b1&&b2}}'
run 0 $x '{{b1:(r1;x1*)}&{b2:(r2;x2*)}}' '{{b1&&b2}:{{r1&&r2};{x1*&x2*}}}'
run 0 $x '{{b1:r1*}&{b2:r2*}}' '{{b1:r1*}&{b2:r2*}}' # Not reduced
run 0 $x '{{r1*;b1}&{r2*;b2}}' '{{r1*;b1}&{r2*;b2}}' # Not reduced
run 0 $x '{{r1*:b1}&{r2*:b2}}' '{{r1*:b1}&{r2*:b2}}' # Not reduced
run 0 $x '{{a;b*;c}&{d;e*}&{f*;g}&{h*}}' \
'{{f*;g}&{h*}&{{a&&d};{e* & {b*;c}}}}'
run 0 $x '{a;(b*;c*;([*0]+{d;e}))*}!' '{a;{b|c|{d;e}}*}!'

121
src/ltlvisit/simplify.cc
View file

@ -1,5 +1,5 @@
// -*- coding: utf-8 -*-
// Copyright (C) 2011, 2012, 2013 Laboratoire de Recherche et
// Copyright (C) 2011, 2012, 2013, 2014 Laboratoire de Recherche et
// Developpement de l'Epita (LRDE).
//
// This file is part of Spot, a model checking library.
@ -3456,22 +3456,14 @@ namespace spot
if (op == multop::Concat)
{
head1->push_back(h->clone());
multop::vec* tail = new multop::vec;
unsigned s = f->size();
for (unsigned j = 1; j < s; ++j)
tail->push_back(f->nth(j)->clone());
tail1->push_back(multop::instance(op, tail));
tail1->push_back(f->all_but(0));
(*i)->destroy();
*i = 0;
}
else if (op == multop::Fusion)
{
head2->push_back(h->clone());
multop::vec* tail = new multop::vec;
unsigned s = f->size();
for (unsigned j = 1; j < s; ++j)
tail->push_back(f->nth(j)->clone());
tail2->push_back(multop::instance(op, tail));
tail2->push_back(f->all_but(0));
(*i)->destroy();
*i = 0;
}
@ -3535,20 +3527,14 @@ namespace spot
if (op == multop::Concat)
{
tail3->push_back(t->clone());
multop::vec* head = new multop::vec;
for (unsigned j = 0; j < s; ++j)
head->push_back(f->nth(j)->clone());
head3->push_back(multop::instance(op, head));
head3->push_back(f->all_but(s));
(*i)->destroy();
*i = 0;
}
else if (op == multop::Fusion)
{
tail4->push_back(t->clone());
multop::vec* head = new multop::vec;
for (unsigned j = 0; j < s; ++j)
head->push_back(f->nth(j)->clone());
head4->push_back(multop::instance(op, head));
head4->push_back(f->all_but(s));
(*i)->destroy();
*i = 0;
}
@ -4155,6 +4141,8 @@ namespace spot
// head1 tail1
// {b1:r1}&{b2:r2} = {b1∧b2}:{r1&r2}
// head2 tail2
// BEWARE: The second rule is correct only when
// both r1 and r2 do not accept [*0].
multop::vec* head1 = new multop::vec;
multop::vec* tail1 = new multop::vec;
@ -4175,22 +4163,20 @@ namespace spot
if (op == multop::Concat)
{
head1->push_back(h->clone());
multop::vec* tail = new multop::vec;
unsigned s = f->size();
for (unsigned j = 1; j < s; ++j)
tail->push_back(f->nth(j)->clone());
tail1->push_back(multop::instance(op, tail));
tail1->push_back(f->all_but(0));
(*i)->destroy();
*i = 0;
}
else if (op == multop::Fusion)
{
const formula* t = f->all_but(0);
if (t->accepts_eword())
{
t->destroy();
continue;
}
head2->push_back(h->clone());
multop::vec* tail = new multop::vec;
unsigned s = f->size();
for (unsigned j = 1; j < s; ++j)
tail->push_back(f->nth(j)->clone());
tail2->push_back(multop::instance(op, tail));
tail2->push_back(t);
(*i)->destroy();
*i = 0;
}
@ -4230,83 +4216,6 @@ namespace spot
delete tail2;
}
// {r1;b1}&{r2;b2} = {r1&r2};{b1∧b2}
// head3 tail3
// {r1:b1}&{r2:b2} = {r1&r2}:{b1∧b2}
// head4 tail4
multop::vec* head3 = new multop::vec;
multop::vec* tail3 = new multop::vec;
multop::vec* head4 = new multop::vec;
multop::vec* tail4 = new multop::vec;
for (multop::vec::iterator i = s.res_other->begin();
i != s.res_other->end(); ++i)
{
if (!*i)
continue;
if ((*i)->kind() != formula::MultOp)
continue;
const multop* f = down_cast<const multop*>(*i);
unsigned s = f->size() - 1;
const formula* t = f->nth(s);
if (!t->is_boolean())
continue;
multop::type op = f->op();
if (op == multop::Concat)
{
tail3->push_back(t->clone());
multop::vec* head = new multop::vec;
for (unsigned j = 0; j < s; ++j)
head->push_back(f->nth(j)->clone());
head3->push_back(multop::instance(op, head));
(*i)->destroy();
*i = 0;
}
else if (op == multop::Fusion)
{
tail4->push_back(t->clone());
multop::vec* head = new multop::vec;
for (unsigned j = 0; j < s; ++j)
head->push_back(f->nth(j)->clone());
head4->push_back(multop::instance(op, head));
(*i)->destroy();
*i = 0;
}
else
{
continue;
}
}
if (!head3->empty())
{
const formula* h =
multop::instance(multop::AndNLM, head3);
const formula* t =
multop::instance(multop::And, tail3);
const formula* f =
multop::instance(multop::Concat, h, t);
s.res_other->push_back(f);
}
else
{
delete head3;
delete tail3;
}
if (!head4->empty())
{
const formula* h =
multop::instance(multop::AndNLM, head4);
const formula* t =
multop::instance(multop::And, tail4);
const formula* f =
multop::instance(multop::Fusion, h, t);
s.res_other->push_back(f);
}
else
{
delete head4;
delete tail4;
}
result_ = multop::instance(multop::AndNLM, s.res_other);
// If we altered the formula in some way, process
// it another time.