diff options
Diffstat (limited to 'gcc/cfghooks.c')
| -rw-r--r-- | gcc/cfghooks.c | 37 |
1 files changed, 35 insertions, 2 deletions
diff --git a/gcc/cfghooks.c b/gcc/cfghooks.c index c4c51cc4404..bc1b7a2f582 100644 --- a/gcc/cfghooks.c +++ b/gcc/cfghooks.c @@ -508,6 +508,7 @@ delete_basic_block (basic_block bb) { loop->header = NULL; loop->latch = NULL; + loops_state_set (LOOPS_NEED_FIXUP); } remove_bb_from_loops (bb); @@ -682,8 +683,18 @@ merge_blocks (basic_block a, basic_block b) cfg_hooks->merge_blocks (a, b); + /* If we merge a loop header into its predecessor, update the loop + structure. */ if (current_loops != NULL) - remove_bb_from_loops (b); + { + if (b->loop_father->header == b) + { + remove_bb_from_loops (a); + add_bb_to_loop (a, b->loop_father); + a->loop_father->header = a; + } + remove_bb_from_loops (b); + } /* Normally there should only be one successor of A and that is B, but partway though the merge of blocks for conditional_execution we'll @@ -998,7 +1009,29 @@ duplicate_block (basic_block bb, edge e, basic_block after) { struct loop *cloop = bb->loop_father; struct loop *copy = get_loop_copy (cloop); - add_bb_to_loop (new_bb, copy ? copy : cloop); + /* If we copied the loop header block but not the loop + we have created a loop with multiple entries. Ditch the loop, + add the new block to the outer loop and arrange for a fixup. */ + if (!copy + && cloop->header == bb) + { + add_bb_to_loop (new_bb, loop_outer (cloop)); + cloop->header = NULL; + cloop->latch = NULL; + loops_state_set (LOOPS_NEED_FIXUP); + } + else + { + add_bb_to_loop (new_bb, copy ? copy : cloop); + /* If we copied the loop latch block but not the loop, adjust + loop state. */ + if (!copy + && cloop->latch == bb) + { + cloop->latch = NULL; + loops_state_set (LOOPS_MAY_HAVE_MULTIPLE_LATCHES); + } + } } return new_bb; |