They're not really "push" anymore but that's because there is no such
thing as push constants in bindless shaders on Intel. They should be
fast enough, though. There is some room for debate here as to whether
we want to do the pull in NIR or push it into the back-end. The
advantage of doing it in the back-end is that it'd be easier to use
MOV_INDIRECT for indirect push constant access rather than falling back
to a dataport message.
Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/7356>
Unlike graphics and compute pipelines, Vulkan ray-tracing pipelines do
not have a single entrypoint. Instead, the raygen shader is specified
as a one-element shader binding table in the vkCmdTraceRay call. This
means that raygen shaders have to be bindless shaders just like any
other ray tracing shader. To launch them, we have a tiny compute shader
that acts as a trampoline and sets up the hotzone and uses btd_spawn to
fire off the raygen shader.
Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/7356>
Anuj Phogat
Jason Ekstrand