[PATCH] D124246: [AMDGPU] Adjust wave priority based on VMEM instructions to avoid duty-cycling.

[Jay Foad via Phabricator via llvm-commits]

foad added inline comments.


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Comment at: llvm/lib/Target/AMDGPU/AMDGPUSetWavePriority.cpp:95
+    return false;
+
+  const GCNSubtarget &ST = MF.getSubtarget<GCNSubtarget>();
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I think it only makes sense to run this pass on kernels (i.e. the entry point of a wave), not on subfunctions, so you should bail out if `!AMDGPU::isKernel(MF.getFunction().getCallingConv())` or similar.


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Comment at: llvm/lib/Target/AMDGPU/AMDGPUSetWavePriority.cpp:131
+    if (MBBInfos[&MBB].MayReachVMEMLoad) {
+      if (MBB.isReturnBlock())
+        PriorityLoweringBlocks.insert(&MBB);
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I could be wrong but I don't think kernels have a normal "return" at the end. Maybe change this to `MBB.succ_empty()` to make it a bit more generic?


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D124246/new/

https://reviews.llvm.org/D124246