[llvm] [ARMISelDAGToDAG] use MO_FrameIndex to represent FrameIndex rather than MO_Register (PR #69654)

[Nick Desaulniers via llvm-commits]

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@@ -2649,9 +2649,9 @@ bool llvm::rewriteARMFrameIndex(MachineInstr &MI, unsigned FrameRegIdx,
   unsigned AddrMode = (Desc.TSFlags & ARMII::AddrModeMask);
   bool isSub = false;
 
-  // Memory operands in inline assembly always use AddrMode2.
+  // Memory operands in inline assembly always use AddrMode_i12.
   if (Opcode == ARM::INLINEASM || Opcode == ARM::INLINEASM_BR)
-    AddrMode = ARMII::AddrMode2;
+    AddrMode = ARMII::AddrMode_i12;
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nickdesaulniers wrote:

this needs the same `InlineAsm::Flag` check as ARMAsmPrinter

https://github.com/llvm/llvm-project/pull/69654