[llvm] [IR][NFC] Introduce Constant::containsMatchingVectorElement and corresponding matcher m_ContainsMatchingVectorElement (PR #200502)

[Ramkumar Ramachandra via llvm-commits]

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artagnon wrote:

Just noting: I think this constant handling is missing in the new code, but I don't think it's necessary, as it will be a fixed-vector type, and we'd check all the aggregate elements?

https://github.com/llvm/llvm-project/pull/200502