https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96370
--- Comment #5 from Richard Biener <rguenth at gcc dot gnu.org> ---
OK, so rewrite_expr_tree isn't prepared to see ops with a three component
"leaf" as try_special_add_to_ops produces which turns { -b, b } into
{ b, b, -1 }. Instead it recurses into the apperant non-leaf _1 which
is the negate.
/* Recurse on the LHS of the binary operator, which is guaranteed to
be the non-leaf side. */
tree new_rhs1
= rewrite_expr_tree (SSA_NAME_DEF_STMT (rhs1), opindex + 1, ops,
changed || oe->op != rhs2 || next_changed,
false);
But I have a simple fix.
