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/* Test the timeout facility of the library.
Copyright (C) 2001-2009 Roberto Bagnara <bagnara@cs.unipr.it>
This file is part of the Parma Polyhedra Library (PPL).
The PPL is free software; you can redistribute it and/or modify it
under the terms of the GNU General Public License as published by the
Free Software Foundation; either version 3 of the License, or (at your
option) any later version.
The PPL is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software Foundation,
Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02111-1307, USA.
For the most up-to-date information see the Parma Polyhedra Library
site: http://www.cs.unipr.it/ppl/ . */
#include "ppl_test.hh"
#include "pwl.hh"
#include "timings.hh"
namespace {
void
compute_open_hypercube_generators(dimension_type dimension) {
NNC_Polyhedron hypercube(dimension);
for (dimension_type i = 0; i < dimension; ++i) {
Variable x(i);
hypercube.add_constraint(x > 0);
hypercube.add_constraint(x < 1);
}
(void) hypercube.generators();
}
class Timeout : virtual public std::exception,
public Parma_Polyhedra_Library::Throwable {
public:
const char* what() const throw() {
return "Timeout in watchdog1.cc";
}
void throw_me() const {
throw *this;
}
int priority() const {
return 0;
}
Timeout() {
}
~Timeout() throw() {
}
};
Timeout t;
bool
timed_compute_open_hypercube_generators(dimension_type dimension,
int hundredth_secs) {
try {
Parma_Watchdog_Library::Watchdog
w(hundredth_secs, abandon_expensive_computations, t);
start_clock();
compute_open_hypercube_generators(dimension);
abandon_expensive_computations = 0;
return true;
}
catch (const Timeout& e) {
abandon_expensive_computations = 0;
nout << e.what() << " after ";
print_clock(nout);
nout << " s" << endl;
return false;
}
#if !PWL_WATCHDOG_OBJECTS_ARE_SUPPORTED
// If Watchdog objects are not supported, an std::logic_error exception
// will be thrown: this is normal.
catch (const std::runtime_error& e) {
nout << "std::runtime_error exception caught: \n" << e.what() << std::endl;
exit(0);
}
#endif // !PWL_WATCHDOG_OBJECTS_ARE_SUPPORTED
catch (...) {
exit(1);
}
// Should never get here.
return false;
}
} // namespace
#define INIT_TIME 20
int
main() TRY {
set_handlers();
// Find a dimension that cannot be computed with a INIT_TIME timeout.
dimension_type dimension = 0;
do {
++dimension;
nout << "Trying dimension " << dimension << endl;
} while (timed_compute_open_hypercube_generators(dimension, INIT_TIME));
// Now find an upper bound to the time necessary to compute it.
int upper_bound = INIT_TIME;
do {
upper_bound *= 2;
nout << "Trying upper bound " << upper_bound << endl;
} while (!timed_compute_open_hypercube_generators(dimension, upper_bound));
// Search the "exact" time.
int lower_bound = upper_bound/2;
do {
int test_time = (lower_bound+upper_bound)/2;
nout << "Probing " << test_time << endl;
if (timed_compute_open_hypercube_generators(dimension, test_time))
upper_bound = test_time;
else
lower_bound = test_time;
} while (upper_bound-lower_bound > 4);
nout << "Estimated time for dimension " << dimension
<< ": " << (lower_bound+upper_bound)/2 << " 100th of sec" << endl;
return 0;
}
CATCH
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