The number of fields comes from the shader, so it could be a value large
enough that using alloca would be problematic.
Fixes: c11833ab24 ("nir,spirv: Rework function calls")
Reviewed-by: Caio Oliveira <caio.oliveira@intel.com>
Reviewed-by: Ryan Neph <ryanneph@google.com>
Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
(cherry picked from commit 9017d37e84)
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/40092>
45ce75f3bc