[llvm] [AArch64][llvm] Redefine some insns as an alias of `SYS` (PR #187004)

[via llvm-commits]

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@@ -919,12 +919,21 @@ bool AArch64InstPrinter::printSysAlias(const MCInst *MI,
   bool OptionalReg = false;
   std::string Ins;
   std::string Name;
+  StringRef RegSep = ", ";
 
   if (CnVal == 7) {
     switch (CmVal) {
     default: return false;
     // MLBI aliases
     case 0: {
+      if (Op1Val == 6 && Op2Val == 0) {
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Lukacma wrote:

If you go back to using aliases I think these changes in printer will also become unnecessary

https://github.com/llvm/llvm-project/pull/187004