[PATCH] D27586: AMDGPU/SI: Add llvm.amdgcn.s.buffer.load intrinsic

[Marek Olšák via Phabricator via llvm-commits]

mareko added a comment.

Would you please describe the purpose of this patch? It's not obvious why it's useful.

What is the behavior of the constant address space in LLVM? Note that vertex buffers and 'restrict' read-only buffers use immutable memory too, so those are also 'constant' and selecting SMEM for those is desirable if it's possible.

OpenGL Constant buffers aren't limited to SMEM. They can be read with a VGPR offset too. LLVM doesn't have the capability to recognize a non-constant SGPR offset at ISel. If you wanna select SMEM with a non-constant offset, you also need to update moveToVALU.


https://reviews.llvm.org/D27586