[llvm] [AMDGPU] NFCI: Track AV Register Pressure separately (PR #149863)

[Lucas Ramirez via llvm-commits]

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@@ -29,43 +29,58 @@ class raw_ostream;
 class SlotIndex;
 
 struct GCNRegPressure {
-  enum RegKind { SGPR, VGPR, AGPR, TOTAL_KINDS };
+  enum RegKind { SGPR, VGPR, AGPR, AVGPR, TOTAL_KINDS };
 
   GCNRegPressure() {
     clear();
   }
 
-  bool empty() const { return !Value[SGPR] && !Value[VGPR] && !Value[AGPR]; }
+  bool empty() const {
+    return !Value[SGPR] && !Value[VGPR] && !Value[AGPR] && !Value[AVGPR];
+  }
 
   void clear() { std::fill(&Value[0], &Value[ValueArraySize], 0); }
 
   /// \returns the SGPR32 pressure
   unsigned getSGPRNum() const { return Value[SGPR]; }
-  /// \returns the aggregated ArchVGPR32, AccVGPR32 pressure dependent upon \p
-  /// UnifiedVGPRFile
+  /// \returns the aggregated ArchVGPR32, AccVGPR32, and Pseudo AVGPR pressure
+  /// dependent upon \p UnifiedVGPRFile
   unsigned getVGPRNum(bool UnifiedVGPRFile) const {
     if (UnifiedVGPRFile) {
-      return Value[AGPR] ? getUnifiedVGPRNum(Value[VGPR], Value[AGPR])
-                         : Value[VGPR];
+      return Value[AGPR]
+                 ? getUnifiedVGPRNum(Value[VGPR], Value[AGPR], Value[AVGPR])
+                 : Value[VGPR] + Value[AVGPR];
     }
-    return std::max(Value[VGPR], Value[AGPR]);
+    // Until we hit the VGPRThreshold, we will assign AV as VGPR. After that
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lucas-rami wrote:

What's the VGPRThreshold? Is it the addressable limit? I think this should be described in a comment somewhere.

https://github.com/llvm/llvm-project/pull/149863