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Diffstat (limited to 'omegalib/omega_lib/src/reach.cc')
| -rw-r--r-- | omegalib/omega_lib/src/reach.cc | 211 |
1 files changed, 211 insertions, 0 deletions
diff --git a/omegalib/omega_lib/src/reach.cc b/omegalib/omega_lib/src/reach.cc new file mode 100644 index 0000000..bde785c --- /dev/null +++ b/omegalib/omega_lib/src/reach.cc @@ -0,0 +1,211 @@ +#include <omega.h> +#include <omega/Relations.h> +#include <basic/Dynamic_Array.h> +#include <omega/reach.h> + +namespace omega { + +typedef Dynamic_Array1<Relation> Rel_Array1; +typedef Dynamic_Array2<Relation> Rel_Array2; + +// This is from parallelism.c, modified + +static void closure_rel(Rel_Array2 &trans, int i, int k, int j) { + Relation tik; + + if (trans[k][k].is_upper_bound_satisfiable()) { + Relation tkk = TransitiveClosure(copy(trans[k][k])); + tkk.simplify(2,4); + tik = Composition(tkk, copy(trans[i][k])); + tik.simplify(2,4); + tik = Union(copy(trans[i][k]), tik); + tik.simplify(2,4); + } + else { + tik = trans[i][k]; + } + Relation fresh; + Relation tkj = trans[k][j]; + fresh = Composition(tkj, tik); + fresh.simplify(2,4); + trans[i][j] = Union(trans[i][j], fresh); + trans[i][j].simplify(2,4); + +#if 0 + fprintf(DebugFile, "%d -> %d -> %d\n", i, k, j); + trans[i][j].print_with_subs(DebugFile); +#endif +} + + +static void close_rels(Rel_Array2 &trans,int n_nodes) { + for (int k=1; k<=n_nodes; k++) + for (int i=1; i<=n_nodes; i++) + if (trans[i][k].is_upper_bound_satisfiable()) + for (int j=1; j<=n_nodes; j++) + if (trans[k][j].is_upper_bound_satisfiable()) + closure_rel(trans, i, k, j); +} + + +void dump_rels(Rel_Array2 &a, reachable_information *reachable_info) { + int i,j; + int n_nodes = reachable_info->node_names.size(); + for(i = 1; i <= n_nodes; i++) + for(j = 1; j <= n_nodes; j++) { + fprintf(stderr,"t[%s][%s] = ", + (reachable_info->node_names[i]).c_str(), + (reachable_info->node_names[j]).c_str()); + a[i][j].print_with_subs(stderr); + } +} + + +void dump_sets(Rel_Array1 &a, reachable_information *reachable_info) { + int i; + int n_nodes = reachable_info->node_names.size(); + for(i = 1; i <= n_nodes; i++) { + fprintf(stderr,"r[%s] = ", (reachable_info->node_names[i]).c_str()); + a[i].print_with_subs(stderr); + } +} + + + +Rel_Array1 *Reachable_Nodes(reachable_information *reachable_info) { + Tuple<std::string> &node_names = reachable_info->node_names; + Tuple<int> &arity = reachable_info->node_arity; + Rel_Array2 &transitions = reachable_info->transitions; + Rel_Array1 &start_nodes = reachable_info->start_nodes; + + int n_nodes = node_names.size(),i,j; + +#define DUMP_INITIAL 1 +#define DUMP_CLOSED 1 + + if(DUMP_INITIAL && relation_debug){ + fprintf(stderr,"Initially:\n"); + dump_rels(transitions, reachable_info); + } + + close_rels(transitions,n_nodes); + + if(DUMP_CLOSED && relation_debug) { + fprintf(stderr,"Closed:\n"); + dump_rels(transitions, reachable_info); + } + + Rel_Array1 *finalp = + new Rel_Array1("node"); + Rel_Array1 &final = *finalp; + final.resize(n_nodes+1); + for (i=1; i<=n_nodes; i++) + final[i] = Relation::False(arity[i]); + + for(i = 1; i <= n_nodes; i++) + for(j = 1; j <= n_nodes; j++) + if(start_nodes[i].is_upper_bound_satisfiable()) + final[j] = Union(final[j], + Composition(copy(transitions[i][j]), + copy(start_nodes[i]))); + return finalp; +} + +static void compute_initially_reachable(Rel_Array1 &r, + Rel_Array1 &start_nodes, + Rel_Array2 &, + Rel_Array2 &closed, + Rel_Array1 &end_nodes, + int n_nodes, Tuple<int> &arity){ + for(int n = 1; n <= n_nodes; n++) + r[n] = Relation::False(arity[n]); + + for(int i = 1; i <= n_nodes; i++) + for(int j = 1; j <= n_nodes; j++) + r[i] = Union(r[i], + Range(Restrict_Domain( + Restrict_Range(copy(closed[j][i]), + copy(end_nodes[i])), + copy(start_nodes[j])))); +} + + +static bool iterate(Rel_Array1 &r, Rel_Array2 &, Rel_Array2 &closed, + Rel_Array1 &, int n_nodes) { + bool changed; + + changed = false; + for(int j = 1; j <= n_nodes; j++) { + for(int i = 1; i <= n_nodes; i++) { + /* look for additional steps from interesting states */ + Relation new_rj = Range(Restrict_Domain(copy(closed[i][j]), + copy(r[i]))); + if(!Must_Be_Subset(copy(new_rj),copy(r[j]))) { + r[j] = Union(r[j],new_rj); + r[j].simplify(2,2); + changed = true; + } + } + } + return changed; +} + + + + +Rel_Array1 *I_Reachable_Nodes(reachable_information *reachable_info) { + bool changed; + + Tuple<std::string> &node_names = reachable_info->node_names; + int n_nodes = node_names.size(); + Tuple<int> &arity = reachable_info->node_arity; + Rel_Array2 &transitions = reachable_info->transitions; + Rel_Array1 &start_nodes = reachable_info->start_nodes; + Rel_Array2 closed("node number","node number"); + closed.resize(n_nodes+1,n_nodes+1); // abuse of dynamic arrays + Rel_Array1 *rp = new Rel_Array1("node number"); + Rel_Array1 &r = *rp; + r.resize(n_nodes+1); // abuse of dynamic arrays + + int i,j; + + Rel_Array1 end_nodes("Hi!"); + end_nodes.resize(n_nodes+1); // for future use + for(int n = 1; n <= n_nodes; n++) end_nodes[n] = Relation::True(arity[n]); + + for(j = 1; j <= n_nodes; j++) { + closed[j][j] = TransitiveClosure(copy(transitions[j][j])); + for(i = 1; i <= n_nodes; i++) + if (i != j) + closed[i][j] = transitions[i][j]; + } + + compute_initially_reachable(r,start_nodes,transitions,closed,end_nodes, + n_nodes,arity); + +#define DUMP_INITIAL 1 +#define DUMP_CLOSED 1 + + if(DUMP_INITIAL && relation_debug > 1) { + fprintf(stderr,"Closed:\n"); + dump_rels(closed, reachable_info); + } + if(DUMP_INITIAL && relation_debug) { + fprintf(stderr,"start nodes:\n"); + dump_sets(start_nodes, reachable_info); + fprintf(stderr,"Initially reachable:\n"); + dump_sets(r, reachable_info); + } + + changed = true; + int iterations = 0, max_iterations = 1000; + while(changed && iterations < max_iterations) { + changed = iterate(r,transitions,closed,start_nodes,n_nodes); + iterations++; + } + if(relation_debug) + fprintf(stdout,"[Iterations to convergence: %d]\n",iterations); + return rp; +} + +} // namespace |