[llvm] [AArch64] merge index address with large offset into base address (PR #75343)

[David Sherwood via llvm-commits]

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@@ -4089,6 +4089,11 @@ AArch64InstrInfo::getLdStOffsetOp(const MachineInstr &MI) {
   return MI.getOperand(Idx);
 }
 
+const MachineOperand &
+AArch64InstrInfo::getLdStAmountOp(const MachineInstr &MI) {
+  return MI.getOperand(4);
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david-arm wrote:

How do you know this is always going to be operand 4 without inspecting the opcode? For example, see the functions above.

https://github.com/llvm/llvm-project/pull/75343