[llvm] Xtensa] Implement windowed call ABI. (PR #130001)

[Matt Arsenault via llvm-commits]

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@@ -1385,6 +1389,16 @@ MachineBasicBlock *XtensaTargetLowering::EmitInstrWithCustomInserter(
     }
     return MBB;
   }
+  case Xtensa::MOVSP_P: {
+    MachineOperand SP = MI.getOperand(0);
+    MachineOperand NewSP = MI.getOperand(1);
+
+    BuildMI(*MBB, MI, DL, TII.get(Xtensa::MOVSP), SP.getReg())
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arsenm wrote:

Could this just have used the call frame pseudos to start 

https://github.com/llvm/llvm-project/pull/130001