The main path discovery function was due for a cleanup. First,
there's a nagging goto and second, my bitmap use was sloppy. Hopefully
this makes the code easier for others to read.
Regstrapped on x86-64 Linux. I also made sure there were no difference
in the number of threads with this patch.
No functional changes.
OK?
gcc/ChangeLog:
* tree-ssa-threadbackward.c (back_threader::find_paths_to_names):
Remove gotos and other cleanups.
---
gcc/tree-ssa-threadbackward.c | 52 ++++++++++++++---------------------
1 file changed, 20 insertions(+), 32 deletions(-)
diff --git a/gcc/tree-ssa-threadbackward.c b/gcc/tree-ssa-threadbackward.c
index b7eaff94567..d6a5b0b8da2 100644
--- a/gcc/tree-ssa-threadbackward.c
+++ b/gcc/tree-ssa-threadbackward.c
@@ -402,26 +402,18 @@ back_threader::find_paths_to_names (basic_block bb,
bitmap interesting)
m_path.safe_push (bb);
+ // Try to resolve the path without looking back.
if (m_path.length () > 1
- && !m_profit.profitable_path_p (m_path, m_name, NULL))
+ && (!m_profit.profitable_path_p (m_path, m_name, NULL)
+ || maybe_register_path ()))
{
m_path.pop ();
m_visited_bbs.remove (bb);
return false;
}
- // Try to resolve the path without looking back.
- if (m_path.length () > 1 && maybe_register_path ())
- {
- m_path.pop ();
- m_visited_bbs.remove (bb);
- return true;
- }
-
auto_bitmap processed;
- unsigned i;
bool done = false;
-
// We use a worklist instead of iterating through the bitmap,
// because we may add new items in-flight.
auto_vec<tree> worklist (bitmap_count_bits (interesting));
@@ -433,34 +425,30 @@ back_threader::find_paths_to_names (basic_block bb,
bitmap interesting)
basic_block def_bb = gimple_bb (SSA_NAME_DEF_STMT (name));
// Process any names defined in this block.
- if (def_bb == bb)
+ if (def_bb == bb
+ && bitmap_set_bit (processed, i)
+ && resolve_def (name, interesting, worklist))
{
- bitmap_set_bit (processed, i);
-
- if (resolve_def (name, interesting, worklist))
- {
- done = true;
- goto leave_bb;
- }
+ done = true;
+ break;
}
}
-
// If there are interesting names not yet processed, keep looking.
- bitmap_and_compl_into (interesting, processed);
- if (!bitmap_empty_p (interesting))
+ if (!done)
{
- edge_iterator iter;
- edge e;
- FOR_EACH_EDGE (e, iter, bb->preds)
- if ((e->flags & EDGE_ABNORMAL) == 0)
- done |= find_paths_to_names (e->src, interesting);
+ bitmap_and_compl_into (interesting, processed);
+ if (!bitmap_empty_p (interesting))
+ {
+ edge_iterator iter;
+ edge e;
+ FOR_EACH_EDGE (e, iter, bb->preds)
+ if ((e->flags & EDGE_ABNORMAL) == 0)
+ done |= find_paths_to_names (e->src, interesting);
+ }
}
- leave_bb:
- bitmap_iterator bi;
- EXECUTE_IF_SET_IN_BITMAP (processed, 0, i, bi)
- bitmap_set_bit (interesting, i);
-
+ // Reset things to their original state.
+ bitmap_ior_into (interesting, processed);
m_path.pop ();
m_visited_bbs.remove (bb);
return done;
--
2.31.1
