[llvm] [IRBuilder][ConstantFold] Fold constant for CreateInsertVector. (PR #116229)

[Nikita Popov via llvm-commits]

https://github.com/nikic requested changes to this pull request.

There shouldn't be an IRBuilderFolder API that is specific to this intrinsic. This is a specific instance of general intrinsic folding support.

https://github.com/llvm/llvm-project/pull/116229