p_is_helper doesn't have any operands, so ACO's value numbering and/or
the pre-RA optimizer could incorrectly recognize two such instructions
as the same.
This patch adds exec as an operand to p_is_helper in order to achieve
correct behavior.
Cc: mesa-stable
Closes: https://gitlab.freedesktop.org/mesa/mesa/-/issues/5570
Signed-off-by: Timur Kristóf <timur.kristof@gmail.com>
Reviewed-by: Daniel Schürmann <daniel@schuermann.dev>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/13577>
(cherry picked from commit d80c7f3406)