This directory contains benchmark scripts for LTL-to-Büchi translators.
They are all based on lbtt.

==========
 CONTENTS
==========

* algorithms

  The lbtt configuration of all the algorithms.  More about these below.

* small
* big
* known

  Run lbtt on, respectively:
    small formulae (size 10, 4 propositions)
    big formulae (size 12..15, 8 propositions)
    known formulae (96 formulae from formulae.ltl)

  Each script generates 3 files:
    xxxx.cfg: the configuration file for lbtt
    xxxx.log: the log of lbtt's execution (also output when the script runs)
    xxxx.txt: the summary of the test (also output at the end of the script)

* ltl2baw.in
* ltl2baw.pl

  ltl2baw.pl is generated from ltl2baw.in by configure.  This perl
  script converts the intermediate generalized automata computed by
  ltl2ba into a form usable by lbtt.

* formulae.ltl

  A list of LTL formulae used by the `known' check.
  See ../emptchk/README for the sources.

* parseout.pl

  This scripts is used to create *.txt files from *.log files.


====================
 ALGORITHMS & TOOLS
====================

The page http://spot.lip6.fr/wiki/LtlTranslationBenchmark explains
all the keys used and the different tools involved in the benchmark.

Spot's configure script checks for the tools needed in the
benchmark, and the script in this directory should omit the tools
that are not available.


=====================
 Running the scripts
=====================

  1) Install all the third-party translators that you want to check.
     They must all be in $PATH and work from there.

     Two difficulties comes from Modella and wring2lbtt:

       * Modella 1.5.7 produces automata that are not readable by lbtt 1.1.2.
         You have to fix the former as follows:

--- modella1.5.7/modella_automa.c	2004-08-30 17:19:47.000000000 +0200
+++ modella1.5.7.fixed/modella_automa.c	2005-04-14 15:07:46.632785000 +0200
@@ -618,6 +618,7 @@ void print_LBA(LBA* b,FILE* output){
 	if(b->R[j]->source==i){
 	  fprintf(output,"%d ",b->R[j]->dest);
 	  print_form_prefix(b->R[j]->label,output);
+	  fputc('\n',output);
 	}
       fprintf(output,"-1 ");


       * The automata produced by Wring are translated to the syntax
         understood by lbtt using `wring2lbtt' (by the same author of
         Modella).  wring2lbtt suffers from the same "lbtt syntax"
         problem described above, you have to fix this too before it
         can be used.

         Also wring2lbtt requires a Wring directory in the directory
         where it is run; that makes it harder to use as a normal tool
         from $PATH.  I use the following wrapper in my $PATH to work
         around this.

#!/bin/sh
cd ~/src/wring2lbtt && ./wring2lbtt "$@"

         This is OK because the filenames supplied by lbtt are absolute.

  2) ./configure Spot, and build it.

     During the configure process you should see lines such as

checking for lbt... lbt
checking for ltl2ba... ltl2ba
checking for modella... modella
checking for script4lbtt.py... script4lbtt.py
checking for spin... spin
checking for wring2lbtt... wring2lbtt

     If some tool is not found, the corresponding tests will be disabled.
     You can also use variables such as LBT, LTL2BA, MODELLA, LTL2NBA,
     SPIN, and WRING2LBTT to specify the location of any of these scripts
     if it is not in $PATH.  For instance

        ./configure LTL2NBA=/home/adl/src/ltlnba/script4lbtt.py

  3) Run `make' to build Spot.

  4) cd into bench/ltl2tgba/ and execute any of
        ./small
        ./big
     or ./known

     Alternatively running `make run' (in that directory) will run all
     three scripts.  If you have a multicore processor, you may want
     to run `make -j3 run' to run these three scripts in parallel.
     None of the tested translators use more than one core.

  5) Wait...

=======================
 Reading the summaries
=======================

The files small.txt, big.txt, and known.txt contain a summary of the
results.  Each algorithm is described as two lines formated as
follows.

    6: Spot FM (degen)
            834 /   2419 /  188 /      2.86      166579 /   8749162   (188)

The first line presents the name of the algorithm ("Spot FM (degen)")
and its number for lbtt (6).  The number is useless.  In this example,
"FM (degen)" means that the Couvreur/FM algorithm is used to translate
LTL formula into a TGBA that is then DEGENeralized.  You may want to
look in the file `algorithms' to see which options are used for each
name, if the naming is unclear.

The second line display 7 values:
  1. the total number of states of all generated automata (834)
  2. the total number of transitions of all generated automata (2419)
  3. the total number of acceptance conditions of all generated automata (188)
  4. the cumulated translation time in seconds (2.86)
  5. the total number of states in the synchronized products (166579)
  6. the total number of transitions in the synchronized products (8749162)
  7. the number of translated formulae (188)

Notes:

  * Small translation times are not accurate because most of the
    translators are run through scripts that translate their input
    from and their output to the format understood by lbtt.  For fast
    translators, most of the time is spent through these wrappers.
    (For instance Spot's ltl2tgba is run through lbtt-translate, and
    depending on how Spot has been configured w.r.t. to dynamic
    libraries, ltl2tgba itself is often a shell script that run the
    real binary with the locally built libraries.)

  * Some tools will appear to have translated fewer automata than the
    others.  This normally indicates bugs in the translator.  In that
    case it is harder to compare the results.  (Normalizing the other
    values accordingly may not be fair: maybe the translator precisely
    failed to translate the largest automata.)
