isl_union_set_compute_schedule: ignore backward proximity edges on split

[platform/upstream/isl.git] / isl_schedule.c

diff --git a/isl_schedule.c b/isl_schedule.c
index 65573f5..7435a55 100644 (file)
--- a/isl_schedule.c
+++ b/isl_schedule.c
@@ -1642,6 +1642,9 @@ static int copy_nodes(struct isl_sched_graph *dst, struct isl_sched_graph *src,
 
 /* Copy non-empty edges that satisfy edge_pred from the src dependence graph
  * to the dst dependence graph.
+ * If the source or destination node of the edge is not in the destination
+ * graph, then it must be a backward proximity edge and it should simply
+ * be ignored.
  */
 static int copy_edges(isl_ctx *ctx, struct isl_sched_graph *dst,
        struct isl_sched_graph *src,
@@ -1653,6 +1656,7 @@ static int copy_edges(isl_ctx *ctx, struct isl_sched_graph *dst,
        for (i = 0; i < src->n_edge; ++i) {
                struct isl_sched_edge *edge = &src->edge[i];
                isl_map *map;
+               struct isl_sched_node *dst_src, *dst_dst;
 
                if (!edge_pred(edge, data))
                        continue;
@@ -1660,12 +1664,19 @@ static int copy_edges(isl_ctx *ctx, struct isl_sched_graph *dst,
                if (isl_map_plain_is_empty(edge->map))
                        continue;
 
+               dst_src = graph_find_node(ctx, dst, edge->src->dim);
+               dst_dst = graph_find_node(ctx, dst, edge->dst->dim);
+               if (!dst_src || !dst_dst) {
+                       if (edge->validity)
+                               isl_die(ctx, isl_error_internal,
+                                       "backward validity edge", return -1);
+                       continue;
+               }
+
                map = isl_map_copy(edge->map);
 
-               dst->edge[dst->n_edge].src =
-                       graph_find_node(ctx, dst, edge->src->dim);
-               dst->edge[dst->n_edge].dst =
-                       graph_find_node(ctx, dst, edge->dst->dim);
+               dst->edge[dst->n_edge].src = dst_src;
+               dst->edge[dst->n_edge].dst = dst_dst;
                dst->edge[dst->n_edge].map = map;
                dst->edge[dst->n_edge].validity = edge->validity;
                dst->edge[dst->n_edge].proximity = edge->proximity;