Same buffer size for BatchQueue and native algo

Ensure buffer size for BatchQueue and the native communication algorithm is the
same in case there is 1 producer and 1 consumer. In case of several
producers or several consumers, the size of the buffer is multiplied by
max(nb producers, nb consumers).

gcc/omp-low.c

@@ -7867,29 +7867,38 @@ prepare_streaming_context (omp_region_p region)
 		 parallel region.  */
 	      for (i = 0; VEC_iterate (stream_p, sinfo->streams, i, stream); ++i)
 		{
-#ifdef BATCHQ_ENABLED
-		  int nb_views = 0;
+		  int nb_views = 0, nb_rviews = 0, nb_wviews = 0;
 
+#ifdef BATCHQ_ENABLED
 		  stream->use_batchQ = 0;
+#endif
 		  for (j = 0; VEC_iterate (view_p, stream->rviews, j, view); ++j)
 		    {
 		      if (INTEGER_CST_CHECK(view->sinfo->num_instances))
-			nb_views += TREE_INT_CST_LOW(view->sinfo->num_instances);
+			{
+			  nb_views += TREE_INT_CST_LOW(view->sinfo->num_instances);
+			  nb_rviews += TREE_INT_CST_LOW(view->sinfo->num_instances);
+			}
 		      else
 		        {
 			  /* Ensure we use generic functions */
 			  nb_views += 2;
+			  nb_rviews += 2;
 			  break;
 			}
 		    }
 		  for (j = 0; VEC_iterate (view_p, stream->wviews, j, view); ++j)
 		    {
 		      if (INTEGER_CST_CHECK(view->sinfo->num_instances))
-			nb_views += TREE_INT_CST_LOW(view->sinfo->num_instances);
+			{
+			  nb_views += TREE_INT_CST_LOW(view->sinfo->num_instances);
+		          nb_wviews += TREE_INT_CST_LOW(view->sinfo->num_instances);
+			}
 		      else
 		        {
 			  /* Ensure we use generic functions */
 			  nb_views += 2;
+			  nb_wviews += 2;
 			  break;
 			}
 		    }
@@ -7903,55 +7912,76 @@ prepare_streaming_context (omp_region_p region)
 		      /* If there are firstprivate views, there should be no write views.  */
 		      gcc_assert (VEC_empty (view_p, stream->wviews));
 		      nb_views ++;
+		      nb_wviews ++;
 		    }
 
+#ifdef BATCHQ_ENABLED
 		  if (nb_views == 2)
 		    stream->use_batchQ = 1;
 #endif
 
 		  tree type_size = TYPE_SIZE_UNIT (stream->element_type);
 		  tree horizon_size;
-#ifdef BATCHQ_ENABLED
 		  tree read_burst_size, write_burst_size, burst_size;
 		  view_p rview, wview;
 
-#endif
-
 		  gsi = gsi_last_bb (sinfo->initialization_bb);
+		  horizon_size = create_tmp_var (size_type_node,
+						 "horizon_size");
+		  burst_size = create_tmp_var (size_type_node,
+					       "burst_size");
+		  rview = VEC_index(view_p, stream->rviews, 0);
+		  read_burst_size = get_view_burst_size (rview, &gsi);
+		  if (VEC_empty (view_p, stream->wviews))
+		      wview = VEC_index(view_p, stream->fpviews, 0);
+		  else
+		      wview = VEC_index(view_p, stream->wviews, 0);
+		  write_burst_size = get_view_burst_size (wview, &gsi);
+		  stmt = gimple_build_assign_with_ops (MAX_EXPR,
+						       burst_size,
+						       read_burst_size,
+						       write_burst_size);
+		  gsi_insert_after (&gsi, stmt, GSI_CONTINUE_LINKING);
+		  /* MAX(read_burst_size, write_burst_size) / type_size */
+		  stmt = gimple_build_assign_with_ops (CEIL_DIV_EXPR,
+						       horizon_size,
+						       burst_size,
+						       type_size);
+		  gsi_insert_after (&gsi, stmt, GSI_CONTINUE_LINKING);
 #ifdef BATCHQ_ENABLED
 		  if (stream->use_batchQ)
+		      fn = built_in_decls[BUILT_IN_GOMP_BATCHQ_CREATE_STREAM];
+		  else
 		    {
-		      horizon_size = create_tmp_var (size_type_node,
-						     "horizon_size");
-		      burst_size = create_tmp_var (size_type_node,
-						   "burst_size");
-		      rview = VEC_index(view_p, stream->rviews, 0);
-		      read_burst_size = get_view_burst_size (rview, &gsi);
-		      if (VEC_empty (view_p, stream->wviews))
-			  wview = VEC_index(view_p, stream->fpviews, 0);
-		      else
-			  wview = VEC_index(view_p, stream->wviews, 0);
-		      write_burst_size = get_view_burst_size (wview, &gsi);
+#endif
+		      tree aggregation_factor, nbwviewscst, nbrviewscst;
+		      tree max_nbviews;
+
+		      aggregation_factor = build_int_cst (size_type_node,
+							  AGGREGATION_FACTOR);
+		      nbwviewscst = build_int_cst (size_type_node, nb_wviews);
+		      nbrviewscst = build_int_cst (size_type_node, nb_rviews);
+		      max_nbviews = create_tmp_var (size_type_node,
+						    "max_nbviews");
 		      stmt = gimple_build_assign_with_ops (MAX_EXPR,
-							   burst_size,
-							   read_burst_size,
-							   write_burst_size);
+							   max_nbviews,
+							   nbrviewscst,
+							   nbrviewscst);
 		      gsi_insert_after (&gsi, stmt, GSI_CONTINUE_LINKING);
-		      /* MAX(read_burst_size, write_burst_size) / type_size */
-		      stmt = gimple_build_assign_with_ops (CEIL_DIV_EXPR,
+		      stmt = gimple_build_assign_with_ops (MULT_EXPR,
+							   horizon_size,
 							   horizon_size,
-							   burst_size,
-							   type_size);
+							   max_nbviews);
+		      gsi_insert_after (&gsi, stmt, GSI_CONTINUE_LINKING);
+		      stmt = gimple_build_assign_with_ops (MULT_EXPR,
+							   horizon_size,
+							   horizon_size,
+							   aggregation_factor);
 		      gsi_insert_after (&gsi, stmt, GSI_CONTINUE_LINKING);
-		      fn = built_in_decls[BUILT_IN_GOMP_BATCHQ_CREATE_STREAM];
-		    }
-		  else
-#endif
-		    {
-		      horizon_size = build_int_cst (size_type_node,
-						    HORIZON);
 		      fn = built_in_decls[BUILT_IN_GOMP_STREAM_CREATE_STREAM];
+#ifdef BATCHQ_ENABLED
 		    }
+#endif
 		    stmt = gimple_build_call (fn, 2, type_size, horizon_size);
 		    gimple_call_set_lhs (stmt, stream->stream);
 		    gsi_insert_after (&gsi, stmt, GSI_CONTINUE_LINKING);