The following builds upon the logic of the PR105679 fix by avoiding
to thread to a known edge that is predicted as probably never executed.
Bootstrapped on x86_64-unknown-linux-gnu, testing in progress.
PR tree-optimization/106495
* tree-ssa-threadbackward.cc
(back_threader_profitability::profitable_path_p): If known_edge
is probably never executed avoid threading.
---
gcc/tree-ssa-threadbackward.cc | 7 +++++++
1 file changed, 7 insertions(+)
diff --git a/gcc/tree-ssa-threadbackward.cc b/gcc/tree-ssa-threadbackward.cc
index 90f5331c265..0519f2a8c4b 100644
--- a/gcc/tree-ssa-threadbackward.cc
+++ b/gcc/tree-ssa-threadbackward.cc
@@ -777,6 +777,13 @@ back_threader_profitability::profitable_path_p (const
vec<basic_block> &m_path,
"exceeds PARAM_MAX_FSM_THREAD_PATH_INSNS.\n");
return false;
}
+ if (taken_edge && probably_never_executed_edge_p (cfun, taken_edge))
+ {
+ if (dump_file && (dump_flags & TDF_DETAILS))
+ fprintf (dump_file, " FAIL: Jump-thread path not considered: "
+ "path leads to probably never executed edge.\n");
+ return false;
+ }
edge entry = find_edge (m_path[m_path.length () - 1],
m_path[m_path.length () - 2]);
if (probably_never_executed_edge_p (cfun, entry))
--
2.35.3
