[llvm] [VectorCombine] Fix duplicate freeze scheduling for shared indexes (PR #213461)

[via llvm-commits]

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ParkHanbum wrote:

These test cases do not trigger the crash, so they do not seem suitable for testing this patch. Could you please check? https://github.com/dtcxzyw/llvm-autoreduce/issues/255 maybe help

https://github.com/llvm/llvm-project/pull/213461