On Mon, 2015-06-29 at 00:11 -0700, Jordan Justen wrote: > On 2015-06-24 07:36:24, Iago Toral wrote: > > On Wed, 2015-06-24 at 15:43 +0300, Francisco Jerez wrote: > > > AFAICT the reason why this (and many of the other changes in GLSL > > > optimization passes) is needed is because SSBO loads have been > > > implemented as ir_expression nodes instead of being lowered into > > > intrinsics (as other side-effectful operations do like > > > ARB_shader_image_load_store and ARB_shader_atomic_counters). This > > > surely broke the assumption of a number of optimization passes that > > > ir_expression nodes behave as pure functions. I guess the reason why > > > you've done it this way is because UBO loads were already being > > > represented as expressions, so I see why you may have wanted to use the > > > same approach for SSBOs even though there is a fundamental difference > > > between the two: UBO loads have no side effects and are constant for a > > > given set of arguments and a given shader execution, SSBO loads and > > > stores are not. SSBO stores couldn't be accommodated into the same > > > framework so easily, and you decided to create a separate ir node for > > > them, what seems inconsistent with loads. Intrinsics would probably > > > have been a good fit for both loads and stores, and would have made all > > > these optimization changes unnecessary... > > > > > > P.S.: Sorry for the late reply, I was on vacation when I was CC'ed. > > > > Right, your assessment about the reasons behind the current > > implementation is correct. I did not realize of these issues when I > > decided to go with the current implementation, now it does look like > > going with GLSL intrinsics would have made things a bit easier. I > > suppose it would make sense to revisit the implementation in the near > > future taking your work on arb_shader_image_load_store as a reference. > > While we're waiting for curro's work to land, I was hoping to review > and let you guys land the first ~30 front end patches. These patches > would allow some compiler tests to pass if the extension is > overridden. (Plus, it would take a big chunk out of this large > series.) > > Unfortunately, I think you should rework the load/store ops as > intrinsics as recommended by curro. > > Once you have the extension working again with intrinsics, could you > re-post the early patches before the 'i965' patches start? > > Does this seem like a reasonable plan?
Sure, that sounds reasonable. Iago _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/mesa-dev
