SPIR-V: Use NIR deref instructions for UBO/SSBO access
This MR begins the process of being able to optimize external memory access by first moving us over to using deref instructions for UBO/SSBO access.
Many of the patches are cleanups or fairly small refactors of NIR or SPIR-V. More notable changes include:
- Reworking some NIR variable modes to properly distinguish between UBOs and other uniforms
- Adding support to
glsl_type
for explicit strides/offsets on types. - Adding a new ptr-as-array deref type to NIR
- Adding a new
nir_opt_deref
pass to optimize ptr-as-array derefs - Relaxing several NIR validation rules
- Adding support for cast derefs to a couple of passes
- Adding UBO/SSBO deref support to
spirv_to_nir
but hidden behind a flag - Enabling the new path in ANV.
All in all, I think I finally have a version of this that I'm actually happy with. It took several iterations to figure out how I wanted to best describe the type information coming out of SPIR-V. The glsl_type
modifications ended up being not nearly as bad as I expected so I went that route.