[PATCH] D105683: [AMDGPU] Allow frontends to disable null export for pixel shaders

[Carl Ritson via Phabricator via llvm-commits]

critson added inline comments.


================
Comment at: llvm/lib/Target/AMDGPU/SILateBranchLowering.cpp:76
   // "null export"
-  if (IsPS) {
+  if (IsPS && HasExports) {
     BuildMI(MBB, I, DL, TII->get(AMDGPU::EXP_DONE))
----------------
ruiling wrote:
> Do you think we need to define a subtarget feature like AllowNoExportPS and check it here? The hardware behavior is different before and after gfx10, if we do not check this hardware difference, then this attributes will be gpu-generation-dependent (frontend should not set this attribute before gfx10). I am not sure whether this sounds a issue to others?
It depends, it seems we are going in the direction that it is up to frontends to ensure correct behaviour of exports.  Rather than adding a subtarget feature we could just add an architecture check here.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D105683/new/

https://reviews.llvm.org/D105683