[llvm] [AArch64] Define constructive EXT_ZZZI pseudo instruction (PR #152552)

[Gaëtan Bossu via llvm-commits]

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@@ -36,7 +36,8 @@ def DestructiveBinary             : DestructiveInstTypeEnum<5>;
 def DestructiveBinaryComm         : DestructiveInstTypeEnum<6>;
 def DestructiveBinaryCommWithRev  : DestructiveInstTypeEnum<7>;
 def DestructiveTernaryCommWithRev : DestructiveInstTypeEnum<8>;
-def DestructiveUnaryPassthru      : DestructiveInstTypeEnum<9>;
+def DestructiveRegRegImmUnpred    : DestructiveInstTypeEnum<9>;
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gbossu wrote:

Note: If someone prefers, I can rename that to `DestructiveTernaryImmUnpred` to match what I think is the existing naming scheme. I just find `DestructiveRegRegImmUnpred` more explicit.

https://github.com/llvm/llvm-project/pull/152552