[llvm] [ARM] Fix MRC cp10 and cp11 warning (PR #126407)

[Oliver Stannard via llvm-commits]

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@@ -77,8 +77,8 @@ static bool getMCRDeprecationInfo(MCInst &MI, const MCSubtargetInfo &STI,
 static bool getMRCDeprecationInfo(MCInst &MI, const MCSubtargetInfo &STI,
                                   std::string &Info) {
   if (STI.hasFeature(llvm::ARM::HasV7Ops) &&
-      ((MI.getOperand(0).isImm() && MI.getOperand(0).getImm() == 10) ||
-       (MI.getOperand(0).isImm() && MI.getOperand(0).getImm() == 11))) {
+      ((MI.getOperand(1).isImm() && MI.getOperand(1).getImm() == 10) ||
+       (MI.getOperand(1).isImm() && MI.getOperand(1).getImm() == 11))) {
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ostannard wrote:

This looks correct to me. Output operands always come first in `MCInst`, so MRC has the destination register first, but MCR has it third, matching the assembly syntax.

https://github.com/llvm/llvm-project/pull/126407