diff options
| author | rguenth <rguenth@138bc75d-0d04-0410-961f-82ee72b054a4> | 2015-03-13 08:52:51 +0000 |
|---|---|---|
| committer | rguenth <rguenth@138bc75d-0d04-0410-961f-82ee72b054a4> | 2015-03-13 08:52:51 +0000 |
| commit | 98b2c85f39b54df3bc2d48b16edf27d3e8703caf (patch) | |
| tree | 8fc2a2876c706f677325a184d1ccf5c45ac26b51 /gcc/tree-cfgcleanup.c | |
| parent | 25959a395efef4c26d979720c98df9a2737a5f1b (diff) | |
| download | gcc-98b2c85f39b54df3bc2d48b16edf27d3e8703caf.tar.gz | |
2015-03-12 Richard Biener <rguenther@suse.de>
PR middle-end/44563
* tree-inline.c (gimple_expand_calls_inline): Walk BB backwards
to avoid quadratic behavior with inline expansion splitting blocks.
* tree-cfgcleanup.c (cleanup_tree_cfg_bb): Do not merge block
with the successor if the predecessor will be merged with it.
* tree-cfg.c (gimple_can_merge_blocks_p): We can't merge the
entry block with its successor.
git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@221410 138bc75d-0d04-0410-961f-82ee72b054a4
Diffstat (limited to 'gcc/tree-cfgcleanup.c')
| -rw-r--r-- | gcc/tree-cfgcleanup.c | 14 |
1 files changed, 12 insertions, 2 deletions
diff --git a/gcc/tree-cfgcleanup.c b/gcc/tree-cfgcleanup.c index f5a21a30f85..e7122e33c28 100644 --- a/gcc/tree-cfgcleanup.c +++ b/gcc/tree-cfgcleanup.c @@ -650,8 +650,18 @@ cleanup_tree_cfg_bb (basic_block bb) if (single_succ_p (bb) && can_merge_blocks_p (bb, single_succ (bb))) { - merge_blocks (bb, single_succ (bb)); - return true; + /* If there is a merge opportunity with the predecessor + do nothing now but wait until we process the predecessor. + This happens when we visit BBs in a non-optimal order and + avoids quadratic behavior with adjusting stmts BB pointer. */ + if (single_pred_p (bb) + && can_merge_blocks_p (single_pred (bb), bb)) + ; + else + { + merge_blocks (bb, single_succ (bb)); + return true; + } } return retval; |