The GIMPLE SSA operand scanner handles COMPONENT_REFs that are
not marked TREE_THIS_VOLATILE but have a TREE_THIS_VOLATILE
FIELD_DECL as volatile. That's inconsistent in how TREE_THIS_VOLATILE
testing on GENERIC refs works which requires operand zero of
component references to mirror TREE_THIS_VOLATILE to the ref
so that testing TREE_THIS_VOLATILE on the outermost reference
is enough to determine the volatileness.
The following patch thus removes FIELD_DECL scanning from
the GIMPLE SSA operand scanner, possibly leaving fewer stmts
marked as gimple_has_volatile_ops.
Bootstrap and regtest running on x86_64-unknown-linux-gnu
(ontop of the earlier posted tree-nested fix)
2021-08-09 Richard Biener <rguent...@suse.de>
* tree-ssa-operands.c (operands_scanner::get_expr_operands):
Do not look at COMPONENT_REF FIELD_DECLs TREE_THIS_VOLATILE
to determine has_volatile_ops.
---
gcc/tree-ssa-operands.c | 7 +------
1 file changed, 1 insertion(+), 6 deletions(-)
diff --git a/gcc/tree-ssa-operands.c b/gcc/tree-ssa-operands.c
index c15575416dd..ebf7eea3b04 100644
--- a/gcc/tree-ssa-operands.c
+++ b/gcc/tree-ssa-operands.c
@@ -834,12 +834,7 @@ operands_scanner::get_expr_operands (tree *expr_p, int
flags)
get_expr_operands (&TREE_OPERAND (expr, 0), flags);
if (code == COMPONENT_REF)
- {
- if (!(flags & opf_no_vops)
- && TREE_THIS_VOLATILE (TREE_OPERAND (expr, 1)))
- gimple_set_has_volatile_ops (stmt, true);
- get_expr_operands (&TREE_OPERAND (expr, 2), uflags);
- }
+ get_expr_operands (&TREE_OPERAND (expr, 2), uflags);
else if (code == ARRAY_REF || code == ARRAY_RANGE_REF)
{
get_expr_operands (&TREE_OPERAND (expr, 1), uflags);
--
2.31.1
