Since we never process loops with inner loops that have been split
we can delay SSA update until after the pass is done with the whole
loop, avoiding the O(function-size) work associated with it.
Bootstrapped and tested on x86_64-unknown-linux-gnu, pushed.
2022-06-28 Richard Biener <rguent...@suse.de>
* tree-ssa-loop-split.cc (fix_loop_bb_probability): Do not
call update_ssa.
---
gcc/tree-ssa-loop-split.cc | 5 ++---
1 file changed, 2 insertions(+), 3 deletions(-)
diff --git a/gcc/tree-ssa-loop-split.cc b/gcc/tree-ssa-loop-split.cc
index d61bad5ba47..bccf621493b 100644
--- a/gcc/tree-ssa-loop-split.cc
+++ b/gcc/tree-ssa-loop-split.cc
@@ -491,8 +491,6 @@ static void
fix_loop_bb_probability (class loop *loop1, class loop *loop2, edge true_edge,
edge false_edge)
{
- update_ssa (TODO_update_ssa);
-
/* Proportion first loop's bb counts except those dominated by true
branch to avoid drop 1s down. */
basic_block *bbs1, *bbs2;
@@ -1668,7 +1666,8 @@ tree_ssa_split_loops (void)
if (loop->aux)
{
/* If any of our inner loops was split, don't split us,
- and mark our containing loop as having had splits as well. */
+ and mark our containing loop as having had splits as well.
+ This allows for delaying SSA update. */
loop_outer (loop)->aux = loop;
continue;
}
--
2.35.3
