[llvm] [AArch64] Implement spill/fill of predicate pair register classes (PR #76068)

[Sander de Smalen via llvm-commits]

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@@ -2221,6 +2222,7 @@ unsigned AArch64InstrInfo::isStoreToStackSlot(const MachineInstr &MI,
   case AArch64::STRDui:
   case AArch64::STRQui:
   case AArch64::STR_PXI:
+  case AArch64::STR_PPXI:
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sdesmalen-arm wrote:

Which test does this change affect?

Given that this store takes two P registers as operands, are the operand numbers below correct? (i.e. is MI.getOperand(1).isFI() ever true for STR_PPXI?

https://github.com/llvm/llvm-project/pull/76068