[llvm] [AMDGPU] Add register usage diagnostics at the point of maximum register pressure. (PR #161850)

[Matt Arsenault via llvm-commits]

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@@ -960,6 +975,16 @@ void GCNScheduleDAGMILive::runSchedStages() {
       RegionLiveOuts.buildLiveRegMap();
   }
 
+#ifdef DUMP_MAX_REG_PRESSURE
+  auto dumpRegUsage = [this]() {
+    dumpMaxRegPressure(MF, GCNRegPressure::VGPR, *LIS, MLI);
+    dumpMaxRegPressure(MF, GCNRegPressure::SGPR, *LIS, MLI);
+    LIS->dump();
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arsenm wrote:

It's still trivial enough to just duplicate 

https://github.com/llvm/llvm-project/pull/161850