[llvm] [AMDGPU] Use correct VGPR threshold for flagging ExcessRP regions in unified register file case (PR #85860)

[Stanislav Mekhanoshin via llvm-commits]

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@@ -974,11 +974,13 @@ void GCNSchedStage::checkScheduling() {
                       << DAG.MinOccupancy << ".\n");
   }
 
-  unsigned MaxVGPRs = ST.getMaxNumVGPRs(MF);
+  unsigned MaxVGPRs = ST.getMaxNumVGPRs(MF, /*WholeRegisterFile*/ true);
+  unsigned MaxArchVGPRs = ST.getMaxNumVGPRs(MF, /*WholeRegisterFile*/ false);
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rampitec wrote:

Do I get this right, after the last change `MaxArchVGPRs` is initialized with the equivalent of `min(MaxVGPRs, getAddressableNumArchVGPRs)`? If so it is easier to do just this.

https://github.com/llvm/llvm-project/pull/85860