pbessolvesymbolic

This is a solving tool for parameterised Boolean equation systems (.pbes extension) that is based on a parity game exploration technique that utilises symbolic representations. The symbolic exploration works very similar to the one implemented by lpsreach, where it is described in great detail. The main difference is that the underlying PBES is first transformed into a standard recursive format (SRF), which is in some sense very similar to a linear process.

Next, we describe useful options that are exclusive to pbessolvesymbolic. One option that can be useful to further refine the dependencies of transition groups is –split-conditions, which introduces new transition groups based on the structure of the SRF pbes and is generally safe.

Similarly to pbessolve the pbessolvesymbolic tool also contains various partial solving strategies that attempt to optimistically solve the intermediate parity games to present the solution (and terminate) early. These can be enabled with the –solve-strategy option.

Limitations

Currently, pbessolvesymbolic can not provide counter examples when the property does not hold, and solving PBESs with counter example information is extremely slow.

This tool is only available on macOS and Linux since the Sylvan dependency cannot be compiled by Visual Studio.

orphan:

Usage

pbessolvesymbolic   [OPTION]... [INFILE [OUTFILE]]

Description

Solves PBES from INFILE. If INFILE is not present, stdin is used. The PBES is first instantiated into a parity game, which is then solved using Zielonka’s algorithm.

Command line options

--cached

use transition group caching to speed up state space exploration

--chaining

reduce the amount of breadth-first iterations by applying the transition groups consecutively

--groups[=GROUPS]

‘none’ (default) no summand groups

‘used’ summands with the same variables are joined ‘simple’ summands with the same read/write variables are joined a user defined list of summand groups separated by semicolons, e.g. ‘0; 1 3 4; 2 5’

--info

print read/write information of the summands

--lace-dqsize[=NUM]

set length of Lace task queue (default 1024*1024*4)

--lace-stacksize[=NUM]

set size of program stack in kilobytes (0=default stack size)

--max-iterations[=NUM]

limit number of breadth-first iterations to NUM

-m[NUM] , --memory-limit[=NUM]

Sylvan memory limit in gigabytes (default 3)

--print-exact

prints the sizes of LDDs exactly when within the representable range, and in scientific notation otherwise

--print-nodesize

print the number of LDD nodes in addition to the number of elements represented as ‘elements[nodes]’

-QNUM , --qlimit=NUM

limit enumeration of universal and existential quantifiers in data expressions to NUM iterations (default NUM=10, NUM=0 for unlimited).

--reorder[=ORDER]

‘none’ (default) no variable reordering

‘random’ variables are put in a random order ‘a user defined permutation e.g. ‘1 3 2 0 4’

--reset

set constant values when introducing parameters

-rNAME , --rewriter=NAME

use rewrite strategy NAME:

jitty

jitty rewriting

jittyc

compiled jitty rewriting

jittyp

jitty rewriting with prover

--saturation

reduce the amount of breadth-first iterations by applying the transition groups until fixed point

-sNUM , --solve-strategy=NUM

Use solve strategy NUM. All strategies except 0 periodically apply on-the-fly solving, which may lead to early termination.

0

No on-the-fly solving is applied

1

Detect solitair winning cycles.

2

Detect solitair winning cycles with safe attractors.

3

Detect forced winning cycles.

4

Detect forced winning cycles with safe attractors.

5

Detect fatal attractors.

6

Detect fatal attractors with safe attractors.

7

Solve subgames using a Zielonka solver.

-c , --split-conditions

split disjunctive conditions to obtain more summands with potentially less dependencies

--threads=NUM

run with NUM threads (default=1). With multiple threads the stack size on a Mac is limited which can lead to bus errors.

--timings[=FILE]

append timing measurements to FILE. Measurements are written to standard error if no FILE is provided

-t , --total

make the SRF PBES total

Standard options

-q , --quiet

do not display warning messages

-v , --verbose

display short log messages

-d , --debug

display detailed log messages

--log-level=LEVEL

display log messages up to and including level; either warn, verbose, debug or trace

-h , --help

display help information

--version

display version information

--help-all

display help information, including hidden and experimental options

Author

Wieger Wesselink