[llvm] [ConstantFolding] Add folding for [de]interleave2, insert and extract (PR #141301)

[Nikolay Panchenko via llvm-commits]

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@@ -0,0 +1,90 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 5
+; RUN: opt < %s -passes=instsimplify,verify -disable-verify -S | FileCheck %s
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npanchen wrote:

That comes from https://github.com/llvm/llvm-project/pull/141301#discussion_r2105744653 comment.
The reason I think it's valid is if such instruction was constructed and being folded within a single pass, verification won't catch it.

https://github.com/llvm/llvm-project/pull/141301