Merge branch 'fix_bliss_maxgenerator_check' into 'v90-bugfix'

fix limits on number of generators

See merge request integer/scip!3305

CHANGELOG

@@ -41,6 +41,7 @@ Features
 - when parsing nonlinear constraints from CIP files, the * after the number in a term is now optional if followed by a variable,
   i.e., instead of 3*<x>*<y>, now also 3<x>*<y> can be read, but 3<x><y> is not supported;
   this allows to read some CIP files that were written with SCIP < 8
+- when running bliss, we now limit the number of actually created generators and not the ones considered by bliss
 
 Performance improvements
 ------------------------

src/symmetry/compute_symmetry_bliss.cpp

@@ -345,29 +345,30 @@ SCIP_RETCODE computeAutomorphisms(
    /* disable component recursion as advised by Tommi Junttila from bliss */
    G->set_component_recursion(false);
 
-   /* do not use a node limit, but set generator limit */
-#ifdef BLISS_PATCH_PRESENT
-   G->set_search_limits(0, (unsigned) maxgenerators);
-#endif
-
    oldtime = SCIPgetSolvingTime(scip);
 #if BLISS_VERSION_MAJOR >= 1 || BLISS_VERSION_MINOR >= 76
    /* lambda function to have access to data and pass it to the blisshook above */
    auto reportglue = [&](unsigned int n, const unsigned int* aut) {
       blisshook((void*)&data, n, aut);
    };
 
-   /* lambda function to have access to stats and terminate the search if maxgenerators are reached */
-   long unsigned int terminatesearch = INT_MAX;
-   if ( maxgenerators != 0 )
-      terminatesearch = (long unsigned int) maxgenerators;
+   /* lambda function to have access to data and terminate the search if maxgenerators are reached */
    auto term = [&]() {
-      return (stats.get_nof_generators() >= terminatesearch);
+      return (maxgenerators != 0 && data.nperms >= maxgenerators); /* check the number of generators that we have created so far */
    };
 
    /* start search */
    G->find_automorphisms(stats, reportglue, term);
 #else
+
+   /* Older bliss versions do not allow to terminate with a limit on the number of generators unless patched. */
+#ifdef BLISS_PATCH_PRESENT
+   /* If patch is present, do not use a node limit, but set generator limit. This approach is not very accurate, since
+    * it limits the generators considered in bliss and not the ones that we generate (the ones that work on the variable
+    * set). */
+   G->set_search_limits(0, (unsigned) maxgenerators);
+#endif
+
    /* start search */
    G->find_automorphisms(stats, blisshook, (void*) &data);
 #endif

src/symmetry/compute_symmetry_sassy_bliss.cpp

@@ -312,18 +312,10 @@ SCIP_RETCODE computeAutomorphisms(
    /* disable component recursion as advised by Tommi Junttila from bliss */
    blissgraph.set_component_recursion(false);
 
-   /* do not use a node limit, but set generator limit */
-#ifdef BLISS_PATCH_PRESENT
-   blissgraph.set_search_limits(0, (unsigned) maxgenerators);
-#endif
-
 #if BLISS_VERSION_MAJOR >= 1 || BLISS_VERSION_MINOR >= 76
-   /* lambda function to have access to stats and terminate the search if maxgenerators are reached */
-   long unsigned int terminatesearch = INT_MAX;
-   if ( maxgenerators != 0 )
-      terminatesearch = (long unsigned int) maxgenerators;
+   /* lambda function to have access to data and terminate the search if maxgenerators are reached */
    auto term = [&]() {
-      return (stats.get_nof_generators() >= terminatesearch);
+      return (maxgenerators != 0 && data.nperms >= maxgenerators); /* check the number of generators that we have created so far */
    };
 
    auto hook = [&](unsigned int n, const unsigned int* aut) {
@@ -333,6 +325,15 @@ SCIP_RETCODE computeAutomorphisms(
    /* start search */
    blissgraph.find_automorphisms(stats, hook, term);
 #else
+
+   /* Older bliss versions do not allow to terminate with a limit on the number of generators unless patched. */
+#ifdef BLISS_PATCH_PRESENT
+   /* If patch is present, do not use a node limit, but set generator limit. This approach is not very accurate, since
+    * it limits the generators considered in bliss and not the ones that we generate (the ones that work on the variable
+    * set). */
+   G->set_search_limits(0, (unsigned) maxgenerators);
+#endif
+
    /* start search */
    blissgraph.find_automorphisms(stats, sassy::preprocessor::bliss_hook, (void*) &sassy);
 #endif