[llvm] [IR] Add llvm.vector.[de]interleave{4,6,8} (PR #139893)

[Luke Lau via llvm-commits]

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@@ -340,6 +340,9 @@ def IIT_ONE_FIFTH_VEC_ARG : IIT_Base<63>;
 def IIT_ONE_SEVENTH_VEC_ARG : IIT_Base<64>;
 def IIT_V2048: IIT_Vec<2048, 65>;
 def IIT_V4096: IIT_Vec<4096, 66>;
+def IIT_ONE_FOURTH_VEC_ARG : IIT_Base<67>;
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lukel97 wrote:

Yes this annoyed me too :) But I wasn't 100% sure if the ordering needs to be kept for backwards compatibility?

https://github.com/llvm/llvm-project/pull/139893