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

[Momchil Velikov 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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momchil-velikov wrote:

Actually, I think the changes are correct and perhaps LDR/STR_ZZXI/etc need to be added here as well.
The store takes a single register as operand (representing a register pair).
Perhaps, I'll be able to construct a test case showing how it makes a difference, say in MachineLICM or in StackSlotColoring.

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