Since the stack pointer may wrap around the stack size in overflow
cases, traversal logic calculates the real stack pointer with
nir_umod_imm(b, stack, args->stack_entries * args->stack_stride).
For ray queries, "stack" was initialized to
"stack_base + local_invocation_idx * 4". This was completely broken, as
the umod would later delete the stack base completely and overwrite the
start of LDS, which belongs to the apps' shared memory.
Instead, add the stack base as a constant offset in the load/store_stack
callback. (This should also save 1 VALU per ray query)
Also, delete radv_ray_traversal_args::stack_base since it's unused now.
Cc: mesa-stable
(cherry picked from commit b046eaf36d)
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/40488>
976efbe12a