https://gcc.gnu.org/g:8e6a25b01becf449d54154b7e83de5f4955cba37
commit r15-4998-g8e6a25b01becf449d54154b7e83de5f4955cba37
Author: Alexandre Oliva <ol...@adacore.com>
Date: Thu Nov 7 02:47:15 2024 -0300
allow vuses in ifcombine blocks
Disallowing vuses in blocks for ifcombine is too strict, and it
prevents usefully moving fold_truth_andor into ifcombine. That
tree-level folder has long ifcombined loads, absent other relevant
side effects.
for gcc/ChangeLog
* tree-ssa-ifcombine.c (bb_no_side_effects_p): Allow vuses,
but not vdefs.
Diff:
---
gcc/tree-ssa-ifcombine.cc | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/gcc/tree-ssa-ifcombine.cc b/gcc/tree-ssa-ifcombine.cc
index 39702929fc01..57b7e4b62f29 100644
--- a/gcc/tree-ssa-ifcombine.cc
+++ b/gcc/tree-ssa-ifcombine.cc
@@ -130,7 +130,7 @@ bb_no_side_effects_p (basic_block bb)
enum tree_code rhs_code;
if (gimple_has_side_effects (stmt)
|| gimple_could_trap_p (stmt)
- || gimple_vuse (stmt)
+ || gimple_vdef (stmt)
/* We need to rewrite stmts with undefined overflow to use
unsigned arithmetic but cannot do so for signed division. */
|| ((ass = dyn_cast <gassign *> (stmt))
