This is similar to intel_miptree_map_blit and intel_buffer_object.c's
temporary blits in i965.
Improves performance of DiRT Rally by 20-25% by eliminating stalls.
Breaks piglit's spec/arb_shader_image_load_store/host-mem-barrier,
by using the GPU to do uploads, exposing a st/mesa issue where it
doesn't give us memory_barrier() calls. This is a pre-existing issue
and will be fixed by a later patch (currently out for review).
Suggested by Chris Wilson, if only to make it obvious to the human
readers that these are volatile reads. It may also be necessary for
the compiler in a few cases.
This commit introduces a new Gallium driver for Intel Gen8+ GPUs,
named 'iris_dri.so' after the hardware.
Developed by:
- Kenneth Graunke (overall driver)
- Dave Airlie (shaders, conditional render, overflow query, Gen8 port)
- Chris Wilson (fencing, pinned memory, ...)
- Jordan Justen (compute shaders)
- Jason Ekstrand (image load store)
- Caio Marcelo de Oliveira Filho (tessellation control passthrough)
- Rafael Antognolli (auxiliary buffer fixes)
- The rest of the i965 contributors and the Mesa community
