[llvm] [AArch64] recognise trn1/trn2 with flipped operands (PR #169858)

[Philip Ginsbach-Chen via llvm-commits]

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@@ -246,6 +246,87 @@ define <4 x float> @vtrnQf(ptr %A, ptr %B) nounwind {
 	ret <4 x float> %tmp5
 }
 
+define <8 x i8> @vtrni8_8first(ptr %A, ptr %B) nounwind {
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ginsbach wrote:

I was trying to follow the naming conventions from [existing tests](https://github.com/llvm/llvm-project/pull/167235/files#diff-0371c06f28d9d7d435a5d259b075e8daa659a967a9163c5768b97459ef6b2f12), but gladly renamed in commit 2.

https://github.com/llvm/llvm-project/pull/169858