Some functions in ppir iterate the ppir_op_info slots arrays looking
for the PPIR_INSTR_SLOT_END token. The dummy/undef internal ops may
appear in the scheduling code and their slots arrays did not contain
that token, which could result in invalid array reads.
Reported by gcc -fsanitize=address.
Signed-off-by: Erico Nunes <nunes.erico@gmail.com>
Reviewed-by: Vasily Khoruzhick <anarsoul@gmail.com>
Cc: 22.0 <mesa-stable>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/14894>