[llvm] MCExpr-ify SIProgramInfo (PR #88257)

[Matt Arsenault via llvm-commits]

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@@ -61,6 +65,21 @@ void AMDGPUVariadicMCExpr::printImpl(raw_ostream &OS,
   case AGVK_Max:
     OS << "max(";
     break;
+  case AGVK_ExtraSGPRs:
+    OS << "extrasgprs(";
+    break;
+  case AGVK_TotalNumVGPRs:
+    OS << "totalnumvgprs(";
+    break;
+  case AGVK_TotalNumVGPRs90A:
+    OS << "totalnumvgprs90a(";
+    break;
+  case AGVK_AlignTo:
+    OS << "alignto(";
+    break;
+  case AGVK_Occupancy:
+    OS << "occupancy(";
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arsenm wrote:

The occupancy isn't a standalone concept, it's derivable from everything else. Why does it need its own expression? 

https://github.com/llvm/llvm-project/pull/88257