2005-03-04 Devang Patel <dpatel@apple.com>
+
+ PR tree-optimization/18815
+ * tree-if-conv.c (combine_blocks): Adjust loop header edges for
+ loops with zero exit edges.
+
+2005-03-04 Devang Patel <dpatel@apple.com>
* doc/invoke.texi: Remove reference to webpage that does not exist.
basic_block bb, exit_bb, merge_target_bb;
unsigned int orig_loop_num_nodes = loop->num_nodes;
unsigned int i;
-
+ unsigned int n_exits;
+ edge *exits = get_loop_exit_edges (loop, &n_exits);
/* Process phi nodes to prepare blocks for merge. */
process_phi_nodes (loop);
continue;
/* It is time to remove this basic block. First remove edges. */
- while (EDGE_COUNT (bb->succs) > 0)
- remove_edge (EDGE_SUCC (bb, 0));
while (EDGE_COUNT (bb->preds) > 0)
remove_edge (EDGE_PRED (bb, 0));
+ /* This is loop latch and loop does not have exit then do not
+ delete this basic block. Just remove its PREDS and reconnect
+ loop->header and loop->latch blocks. */
+ if (bb == loop->latch && n_exits == 0)
+ {
+ exits = NULL; /* To suppress unused warning. */
+ make_edge (loop->header, loop->latch, EDGE_FALLTHRU);
+ set_immediate_dominator (CDI_DOMINATORS, loop->latch, loop->header);
+ continue;
+ }
+
+ while (EDGE_COUNT (bb->succs) > 0)
+ remove_edge (EDGE_SUCC (bb, 0));
+
/* Remove labels and make stmts member of loop->header. */
for (bsi = bsi_start (bb); !bsi_end_p (bsi); )
{