[llvm] [AMDGPU] Support block load/store for CSR (PR #130013)

[Matt Arsenault via llvm-commits]

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@@ -72,6 +76,9 @@ class CalleeSavedInfo {
   bool isRestored()                        const { return Restored; }
   void setRestored(bool R)                       { Restored = R; }
   bool isSpilledToReg()                    const { return SpilledToReg; }
+
+  bool isHandledByTarget() const { return IsHandledByTarget; }
+  void setHandledByTarget() { IsHandledByTarget = true; }
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arsenm wrote:

Can you just override spillCalleeSavedRegisters/restoreCalleeSavesRegisters? Why do we need a parallel customization mechanism in the same code?

https://github.com/llvm/llvm-project/pull/130013