Refactoring sese.h and graphite-poly.h

Rename scop->region to scop->scop_info
Removed conversion constructors for sese_l and dr_info.
Removed macros.

No functional changed intended. Passes regtest and bootstrap.

gcc/ChangeLog:

2015-19-10  Aditya Kumar  <aditya.k7@samsung.com>
        * graphite-poly.h (struct dr_info): Removed conversion constructor.
        (struct scop): Renamed scop::region to scop::scop_info
        (scop_set_region): Same.
        (SCOP_REGION): Removed
        (SCOP_CONTEXT): Removed.
        (POLY_SCOP_P): Removed.
        * graphite-isl-ast-to-gimple.c (translate_isl_ast_node_user):
        Rename scop->region to scop->scop_info.
        (add_parameters_to_ivs_params): Same.
        (graphite_regenerate_ast_isl): Same.
        * graphite-poly.c (new_scop): Same.
        (free_scop): Same.
        (print_scop_params): Same.
        * graphite-scop-detection.c (scop_detection::remove_subscops): Same.
        (scop_detection::remove_intersecting_scops): Use pointer to sese_l.
        (dot_all_scops_1): Rename scop->region to scop->scop_info.
        (scop_detection::nb_pbbs_in_loops): Same.
        (find_scop_parameters): Same.
        (try_generate_gimple_bb): Same.
        (gather_bbs::before_dom_children): Same.
        (gather_bbs::after_dom_children): Same.
        (build_scops): Same.
        * graphite-sese-to-poly.c (build_scop_scattering): Same.
        (extract_affine_chrec): Same.
        (extract_affine): Same.
        (set_scop_parameter_dim): Same.
        (build_loop_iteration_domains): Same.
        (create_pw_aff_from_tree): Same.
        (add_param_constraints): Same.
        (build_scop_iteration_domain): Same.
        (build_scop_drs): Same.
        (analyze_drs_in_stmts): Same.
        (insert_out_of_ssa_copy_on_edge): Same.
        (rewrite_close_phi_out_of_ssa):Same.
        (rewrite_reductions_out_of_ssa):Same.
        (handle_scalar_deps_crossing_scop_limits):Same.
        (rewrite_cross_bb_scalar_deps):Same.
        (rewrite_cross_bb_scalar_deps_out_of_ssa):Same.
        (build_poly_scop):Same.
        (build_alias_set): Use pointer to dr_info.
        * graphite.c (print_graphite_scop_statistics):
        (graphite_transform_loops):
        * sese.h (struct sese_l): Remove conversion constructor.

From-SVN: r229135

gcc/ChangeLog

+2015-10-21  Aditya Kumar  <aditya.k7@samsung.com>
+
+	* graphite-poly.h (struct dr_info): Removed conversion constructor.
+	(struct scop): Renamed scop::region to scop::scop_info
+	(scop_set_region): Same.
+	(SCOP_REGION): Removed
+	(SCOP_CONTEXT): Removed.
+	(POLY_SCOP_P): Removed.
+	* graphite-isl-ast-to-gimple.c (translate_isl_ast_node_user):
+	Rename scop->region to scop->scop_info.
+	(add_parameters_to_ivs_params): Same.
+	(graphite_regenerate_ast_isl): Same.
+	* graphite-poly.c (new_scop): Same.
+	(free_scop): Same.
+	(print_scop_params): Same.
+	* graphite-scop-detection.c (scop_detection::remove_subscops): Same.
+	(scop_detection::remove_intersecting_scops): Use pointer to sese_l.
+	(dot_all_scops_1): Rename scop->region to scop->scop_info.
+	(scop_detection::nb_pbbs_in_loops): Same.
+	(find_scop_parameters): Same.
+	(try_generate_gimple_bb): Same.
+	(gather_bbs::before_dom_children): Same.
+	(gather_bbs::after_dom_children): Same.
+	(build_scops): Same.
+	* graphite-sese-to-poly.c (build_scop_scattering): Same.
+	(extract_affine_chrec): Same.
+	(extract_affine): Same.
+	(set_scop_parameter_dim): Same.
+	(build_loop_iteration_domains): Same.
+	(create_pw_aff_from_tree): Same.
+	(add_param_constraints): Same.
+	(build_scop_iteration_domain): Same.
+	(build_scop_drs): Same.
+	(analyze_drs_in_stmts): Same.
+	(insert_out_of_ssa_copy_on_edge): Same.
+	(rewrite_close_phi_out_of_ssa):Same.
+	(rewrite_reductions_out_of_ssa):Same.
+	(handle_scalar_deps_crossing_scop_limits):Same.
+	(rewrite_cross_bb_scalar_deps):Same.
+	(rewrite_cross_bb_scalar_deps_out_of_ssa):Same.
+	(build_poly_scop):Same.
+	(build_alias_set): Use pointer to dr_info.
+	* graphite.c (print_graphite_scop_statistics):
+	(graphite_transform_loops):
+	* sese.h (struct sese_l): Remove conversion constructor.
+
 2015-10-11  Jan Hubicka  <hubicka@ucw.cz>
 
 	PR middle-end/67966

gcc/graphite-isl-ast-to-gimple.c

@@ -786,10 +786,10 @@ translate_isl_ast_node_user (__isl_keep isl_ast_node *node,
   iv_map.create (nb_loops);
   iv_map.safe_grow_cleared (nb_loops);
 
-  build_iv_mapping (iv_map, gbb, user_expr, ip, pbb->scop->region->region);
+  build_iv_mapping (iv_map, gbb, user_expr, ip, pbb->scop->scop_info->region);
   isl_ast_expr_free (user_expr);
   next_e = copy_bb_and_scalar_dependences (GBB_BB (gbb),
-					   pbb->scop->region, next_e,
+					   pbb->scop->scop_info, next_e,
 					   iv_map,
 					   &graphite_regenerate_error);
   iv_map.release ();
@@ -909,7 +909,7 @@ print_isl_ast_node (FILE *file, __isl_keep isl_ast_node *node,
 static void
 add_parameters_to_ivs_params (scop_p scop, ivs_params &ip)
 {
-  sese_info_p region = scop->region;
+  sese_info_p region = scop->scop_info;
   unsigned nb_parameters = isl_set_dim (scop->param_context, isl_dim_param);
   gcc_assert (nb_parameters == SESE_PARAMS (region).length ());
   unsigned i;
@@ -1144,7 +1144,7 @@ bool
 graphite_regenerate_ast_isl (scop_p scop)
 {
   loop_p context_loop;
-  sese_info_p region = scop->region;
+  sese_info_p region = scop->scop_info;
   ifsese if_region = NULL;
   isl_ast_node *root_node;
   ivs_params ip;

gcc/graphite-poly.c

@@ -306,7 +306,7 @@ new_scop (edge entry, edge exit)
   scop->may_waw_no_source = NULL;
   scop_set_region (scop, region);
   scop->pbbs.create (3);
-  POLY_SCOP_P (scop) = false;
+  scop->poly_scop_p = false;
   scop->drs.create (3);
 
   return scop;
@@ -321,7 +321,7 @@ free_scop (scop_p scop)
   poly_bb_p pbb;
 
   remove_gbbs_in_scop (scop);
-  free_sese_info (SCOP_REGION (scop));
+  free_sese_info (scop->scop_info);
 
   FOR_EACH_VEC_ELT (scop->pbbs, i, pbb)
     free_poly_bb (pbb);
@@ -475,13 +475,13 @@ print_pbb (FILE *file, poly_bb_p pbb)
 void
 print_scop_params (FILE *file, scop_p scop)
 {
-  if (SESE_PARAMS (SCOP_REGION (scop)).is_empty ())
+  if (SESE_PARAMS (scop->scop_info).is_empty ())
     return;
 
   int i;
   tree t;
   fprintf (file, "parameters (");
-  FOR_EACH_VEC_ELT (SESE_PARAMS (SCOP_REGION (scop)), i, t)
+  FOR_EACH_VEC_ELT (SESE_PARAMS (scop->scop_info), i, t)
     {
       print_generic_expr (file, t, 0);
       fprintf (file, ", ");

gcc/graphite-poly.h

@@ -387,12 +387,6 @@ struct dr_info
   dr_info (data_reference_p dr, int alias_set, poly_bb_p pbb)
     : dr (dr), alias_set (alias_set), pbb (pbb) {}
 
-  /* A simpler constructor to be able to push these objects in a vec.  */
-  dr_info (int i) : dr (NULL), alias_set (-1), pbb (NULL)
-  {
-    gcc_assert (i == 0);
-  }
-
   /* Assignment operator, to be able to iterate over a vec of these objects.  */
   const dr_info &
   operator= (const dr_info &p)
@@ -409,7 +403,7 @@ struct dr_info
 struct scop
 {
   /* A SCOP is defined as a SESE region.  */
-  sese_info_p region;
+  sese_info_p scop_info;
 
   /* Number of parameters in SCoP.  */
   graphite_dim_t nb_params;
@@ -453,10 +447,6 @@ struct scop
   bool poly_scop_p;
 };
 
-#define SCOP_REGION(S) (S->region)
-#define SCOP_CONTEXT(S) (NULL)
-#define POLY_SCOP_P(S) (S->poly_scop_p)
-
 extern scop_p new_scop (edge, edge);
 extern void free_scop (scop_p);
 extern gimple_poly_bb_p new_gimple_poly_bb (basic_block, vec<data_reference_p>);
@@ -471,7 +461,7 @@ extern bool apply_poly_transforms (scop_p);
 static inline void
 scop_set_region (scop_p scop, sese_info_p region)
 {
-  scop->region = region;
+  scop->scop_info = region;
 }
 
 /* Returns the number of parameters for SCOP.  */

gcc/graphite-scop-detection.c

@@ -491,7 +491,7 @@ private:
   vec<sese_l> scops;
 };
 
-sese_l scop_detection::invalid_sese (0);
+sese_l scop_detection::invalid_sese (NULL, NULL);
 
 /* Return an sese_l around the LOOP.  */
 
@@ -888,13 +888,13 @@ void
 scop_detection::remove_subscops (sese_l s1)
 {
   int j;
-  sese_l s2 (0);
+  sese_l *s2;
   FOR_EACH_VEC_ELT_REVERSE (scops, j, s2)
     {
-      if (subsumes (s1, s2))
+      if (subsumes (s1, *s2))
 	{
 	  DEBUG_PRINT (dp << "\nRemoving sub-SCoP";
-		       print_sese (dump_file, s2));
+		       print_sese (dump_file, *s2));
 	  scops.unordered_remove (j);
 	}
     }
@@ -923,13 +923,13 @@ void
 scop_detection::remove_intersecting_scops (sese_l s1)
 {
   int j;
-  sese_l s2 (0);
+  sese_l *s2;
   FOR_EACH_VEC_ELT_REVERSE (scops, j, s2)
     {
-      if (intersects (s1, s2))
+      if (intersects (s1, *s2))
 	{
 	  DEBUG_PRINT (dp << "\nRemoving intersecting SCoP";
-		       print_sese (dump_file, s2); dp << "Intersects with:";
+		       print_sese (dump_file, *s2); dp << "Intersects with:";
 		       print_sese (dump_file, s1));
 	  scops.unordered_remove (j);
 	}
@@ -1273,7 +1273,7 @@ dot_all_scops_1 (FILE *file, vec<scop_p> scops)
       /* Select color for SCoP.  */
       FOR_EACH_VEC_ELT (scops, i, scop)
 	{
-	  sese_l region = scop->region->region;
+	  sese_l region = scop->scop_info->region;
 	  if (bb_in_sese_p (bb, region) || (region.exit->dest == bb)
 	      || (region.entry->dest == bb))
 	    {
@@ -1482,7 +1482,7 @@ scop_detection::nb_pbbs_in_loops (scop_p scop)
   int res = 0;
 
   FOR_EACH_VEC_ELT (scop->pbbs, i, pbb)
-    if (loop_in_sese_p (gbb_loop (PBB_BLACK_BOX (pbb)), scop->region->region))
+    if (loop_in_sese_p (gbb_loop (PBB_BLACK_BOX (pbb)), scop->scop_info->region))
       res++;
 
   return res;
@@ -1623,7 +1623,7 @@ static void
 find_scop_parameters (scop_p scop)
 {
   unsigned i;
-  sese_info_p region = scop->region;
+  sese_info_p region = scop->scop_info;
   struct loop *loop;
 
   /* Find the parameters used in the loop bounds.  */
@@ -1655,7 +1655,7 @@ try_generate_gimple_bb (scop_p scop, basic_block bb)
 {
   vec<data_reference_p> drs;
   drs.create (5);
-  sese_l region = scop->region->region;
+  sese_l region = scop->scop_info->region;
   loop_p nest = outermost_loop_in_sese (region, bb);
 
   loop_p loop = bb->loop_father;
@@ -1700,7 +1700,7 @@ gather_bbs::gather_bbs (cdi_direction direction, scop_p scop)
 void
 gather_bbs::before_dom_children (basic_block bb)
 {
-  if (!bb_in_sese_p (bb, scop->region->region))
+  if (!bb_in_sese_p (bb, scop->scop_info->region))
     return;
 
   gcond *stmt = single_pred_cond_non_loop_exit (bb);
@@ -1717,7 +1717,7 @@ gather_bbs::before_dom_children (basic_block bb)
 	cases.safe_push (NULL);
     }
 
-  scop->region->bbs.safe_push (bb);
+  scop->scop_info->bbs.safe_push (bb);
 
   gimple_poly_bb_p gbb = try_generate_gimple_bb (scop, bb);
   GBB_CONDITIONS (gbb) = conditions.copy ();
@@ -1733,7 +1733,7 @@ gather_bbs::before_dom_children (basic_block bb)
 void
 gather_bbs::after_dom_children (basic_block bb)
 {
-  if (!bb_in_sese_p (bb, scop->region->region))
+  if (!bb_in_sese_p (bb, scop->scop_info->region))
     return;
 
   if (single_pred_cond_non_loop_exit (bb))
@@ -1760,10 +1760,10 @@ build_scops (vec<scop_p> *scops)
   /* Now create scops from the lightweight SESEs.  */
   vec<sese_l> scops_l = sb.get_scops ();
   int i;
-  sese_l s (0);
+  sese_l *s;
   FOR_EACH_VEC_ELT (scops_l, i, s)
     {
-      scop_p scop = new_scop (s.entry, s.exit);
+      scop_p scop = new_scop (s->entry, s->exit);
 
       /* Record all basic blocks and their conditions in REGION.  */
       gather_bbs (CDI_DOMINATORS, scop).walk (cfun->cfg->x_entry_block_ptr);
@@ -1777,7 +1777,7 @@ build_scops (vec<scop_p> *scops)
 	  continue;
 	}
 
-      build_sese_loop_nests (scop->region);
+      build_sese_loop_nests (scop->scop_info);
 
       find_scop_parameters (scop);
       graphite_dim_t max_dim = PARAM_VALUE (PARAM_GRAPHITE_MAX_NB_SCOP_PARAMS);

gcc/graphite-sese-to-poly.c

@@ -335,7 +335,7 @@ build_scop_scattering (scop_p scop)
       int prefix = 0;
 
       if (previous_gbb)
-	prefix = nb_common_loops (scop->region->region, previous_gbb, gbb);
+	prefix = nb_common_loops (scop->scop_info->region, previous_gbb, gbb);
 
       previous_gbb = gbb;
 
@@ -357,7 +357,7 @@ extract_affine_chrec (scop_p s, tree e, __isl_take isl_space *space)
   isl_pw_aff *lhs = extract_affine (s, CHREC_LEFT (e), isl_space_copy (space));
   isl_pw_aff *rhs = extract_affine (s, CHREC_RIGHT (e), isl_space_copy (space));
   isl_local_space *ls = isl_local_space_from_space (space);
-  unsigned pos = sese_loop_depth (s->region->region, get_chrec_loop (e)) - 1;
+  unsigned pos = sese_loop_depth (s->scop_info->region, get_chrec_loop (e)) - 1;
   isl_aff *loop = isl_aff_set_coefficient_si
     (isl_aff_zero_on_domain (ls), isl_dim_in, pos, 1);
   isl_pw_aff *l = isl_pw_aff_from_aff (loop);
@@ -539,8 +539,8 @@ extract_affine (scop_p s, tree e, __isl_take isl_space *space)
       break;
 
     case SSA_NAME:
-      gcc_assert (-1 != parameter_index_in_region_1 (e, s->region)
-		  || !invariant_in_sese_p_rec (e, s->region->region));
+      gcc_assert (-1 != parameter_index_in_region_1 (e, s->scop_info)
+		  || !invariant_in_sese_p_rec (e, s->scop_info->region));
       res = extract_affine_name (s, e, space);
       break;
 
@@ -571,7 +571,7 @@ extract_affine (scop_p s, tree e, __isl_take isl_space *space)
 static void
 set_scop_parameter_dim (scop_p scop)
 {
-  sese_info_p region = scop->region;
+  sese_info_p region = scop->scop_info;
   unsigned nbp = sese_nb_params (region);
   isl_space *space = isl_space_set_alloc (scop->isl_context, nbp, 0);
 
@@ -594,7 +594,7 @@ build_loop_iteration_domains (scop_p scop, struct loop *loop,
 {
 
   tree nb_iters = number_of_latch_executions (loop);
-  sese_l region = scop->region->region;
+  sese_l region = scop->scop_info->region;
   gcc_assert (loop_in_sese_p (loop, region));
 
   isl_set *inner = isl_set_copy (outer);
@@ -704,7 +704,7 @@ create_pw_aff_from_tree (poly_bb_p pbb, tree t)
 {
   scop_p scop = PBB_SCOP (pbb);
 
-  t = scalar_evolution_in_region (scop->region->region, pbb_loop (pbb), t);
+  t = scalar_evolution_in_region (scop->scop_info->region, pbb_loop (pbb), t);
   gcc_assert (!automatically_generated_chrec_p (t));
 
   return extract_affine (scop, t, isl_set_get_space (pbb->domain));
@@ -818,7 +818,7 @@ add_conditions_to_constraints (scop_p scop)
 static void
 add_param_constraints (scop_p scop, graphite_dim_t p)
 {
-  tree parameter = SESE_PARAMS (scop->region)[p];
+  tree parameter = SESE_PARAMS (scop->scop_info)[p];
   tree type = TREE_TYPE (parameter);
   tree lb = NULL_TREE;
   tree ub = NULL_TREE;
@@ -892,7 +892,7 @@ build_scop_context (scop_p scop)
 static void
 build_scop_iteration_domain (scop_p scop)
 {
-  sese_info_p region = scop->region;
+  sese_info_p region = scop->scop_info;
   int nb_loops = number_of_loops (cfun);
   isl_set **doms = XCNEWVEC (isl_set *, nb_loops);
 
@@ -1103,13 +1103,13 @@ build_alias_set (scop_p scop)
 {
   int num_vertices = scop->drs.length ();
   struct graph *g = new_graph (num_vertices);
-  dr_info dr1 (0), dr2 (0);
+  dr_info *dr1, *dr2;
   int i, j;
   int *all_vertices;
 
   FOR_EACH_VEC_ELT (scop->drs, i, dr1)
     for (j = i+1; scop->drs.iterate (j, &dr2); j++)
-      if (dr_may_alias_p (dr1.dr, dr2.dr, true))
+      if (dr_may_alias_p (dr1->dr, dr2->dr, true))
 	{
 	  add_edge (g, i, j);
 	  add_edge (g, j, i);
@@ -1155,9 +1155,9 @@ build_scop_drs (scop_p scop)
 
   build_alias_set (scop);
 
-  dr_info dri (0);
+  dr_info *dri;
   FOR_EACH_VEC_ELT (scop->drs, i, dri)
-    build_poly_dr (dri);
+    build_poly_dr (*dri);
 }
 
 /* Analyze all the data references of STMTS and add them to the
@@ -1166,7 +1166,7 @@ build_scop_drs (scop_p scop)
 static void
 analyze_drs_in_stmts (scop_p scop, basic_block bb, vec<gimple *> stmts)
 {
-  sese_l region = scop->region->region;
+  sese_l region = scop->scop_info->region;
   if (!bb_in_sese_p (bb, region))
     return;
 
@@ -1283,7 +1283,7 @@ insert_out_of_ssa_copy_on_edge (scop_p scop, edge e, tree res, tree expr)
   gsi_commit_edge_inserts ();
   basic_block bb = gimple_bb (stmt);
 
-  if (!bb_in_sese_p (bb, scop->region->region))
+  if (!bb_in_sese_p (bb, scop->scop_info->region))
     return;
 
   if (!gbb_from_bb (bb))
@@ -1365,7 +1365,7 @@ propagate_expr_outside_region (tree def, tree expr, sese_l &region)
 static void
 rewrite_close_phi_out_of_ssa (scop_p scop, gimple_stmt_iterator *psi)
 {
-  sese_l region = scop->region->region;
+  sese_l region = scop->scop_info->region;
   gimple *phi = gsi_stmt (*psi);
   tree res = gimple_phi_result (phi);
   basic_block bb = gimple_bb (phi);
@@ -1498,7 +1498,7 @@ static void
 rewrite_reductions_out_of_ssa (scop_p scop)
 {
   basic_block bb;
-  sese_l region = scop->region->region;
+  sese_l region = scop->scop_info->region;
 
   FOR_EACH_BB_FN (bb, cfun)
     if (bb_in_sese_p (bb, region))
@@ -1563,7 +1563,7 @@ handle_scalar_deps_crossing_scop_limits (scop_p scop, tree def, gimple *stmt)
   tree var = create_tmp_reg (TREE_TYPE (def));
   tree new_name = make_ssa_name (var, stmt);
   bool needs_copy = false;
-  sese_l region = scop->region->region;
+  sese_l region = scop->scop_info->region;
 
   imm_use_iterator imm_iter;
   gimple *use_stmt;
@@ -1601,7 +1601,7 @@ handle_scalar_deps_crossing_scop_limits (scop_p scop, tree def, gimple *stmt)
 static bool
 rewrite_cross_bb_scalar_deps (scop_p scop, gimple_stmt_iterator *gsi)
 {
-  sese_l region = scop->region->region;
+  sese_l region = scop->scop_info->region;
   gimple *stmt = gsi_stmt (*gsi);
   imm_use_iterator imm_iter;
   tree def;
@@ -1686,7 +1686,7 @@ rewrite_cross_bb_scalar_deps_out_of_ssa (scop_p scop)
 {
   basic_block bb;
   gimple_stmt_iterator psi;
-  sese_l region = scop->region->region;
+  sese_l region = scop->scop_info->region;
   bool changed = false;
 
   /* Create an extra empty BB after the scop.  */
@@ -1729,6 +1729,6 @@ build_poly_scop (scop_p scop)
 
   /* This SCoP has been translated to the polyhedral
      representation.  */
-  POLY_SCOP_P (scop) = true;
+  scop->poly_scop_p = true;
 }
 #endif  /* HAVE_isl */

gcc/graphite.c

@@ -144,7 +144,7 @@ print_graphite_scop_statistics (FILE* file, scop_p scop)
       gimple_stmt_iterator psi;
       loop_p loop = bb->loop_father;
 
-      if (!bb_in_sese_p (bb, scop->region->region))
+      if (!bb_in_sese_p (bb, scop->scop_info->region))
 	continue;
 
       n_bbs++;
@@ -162,7 +162,7 @@ print_graphite_scop_statistics (FILE* file, scop_p scop)
 	  n_p_stmts += bb->count;
 	}
 
-      if (loop->header == bb && loop_in_sese_p (loop, scop->region->region))
+      if (loop->header == bb && loop_in_sese_p (loop, scop->scop_info->region))
 	{
 	  n_loops++;
 	  n_p_loops += bb->count;
@@ -171,8 +171,8 @@ print_graphite_scop_statistics (FILE* file, scop_p scop)
 
   fprintf (file, "\nFunction Name: %s\n", current_function_name ());
 
-  edge scop_begin = scop->region->region.entry;
-  edge scop_end = scop->region->region.exit;
+  edge scop_begin = scop->scop_info->region.entry;
+  edge scop_end = scop->scop_info->region.exit;
 
   fprintf (file, "\nSCoP (entry_edge (bb_%d, bb_%d), ",
 	   scop_begin->src->index, scop_begin->dest->index);
@@ -334,7 +334,7 @@ graphite_transform_loops (void)
 	if (dump_file && dump_flags)
 	  print_scop (dump_file, scop);
 
-	if (POLY_SCOP_P (scop)
+	if (scop->poly_scop_p
 	    && apply_poly_transforms (scop)
 	    && graphite_regenerate_ast_isl (scop))
 	  need_cfg_cleanup_p = true;

gcc/sese.h

@@ -30,9 +30,6 @@ struct sese_l
 {
   sese_l (edge e, edge x) : entry (e), exit (x) {}
 
-  /* This is to push objects of sese_l in a vec.  */
-  sese_l (int i) : entry (NULL), exit (NULL) { gcc_assert (i == 0); }
-
   operator bool () const { return entry && exit; }
 
   const sese_l &