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

[Benjamin Maxwell 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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MacDue wrote:

I think it would be nice if the test names somewhat follow the possible cases (or at least some comments for them). E.g. `vtrn2_flipped`, `vtrn1`, `vtrn1_flipped`.



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