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

[Aditya prakash jha via llvm-commits]

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AdityaOP007 wrote:

Thanks for checking! You're right, the current test doesn't reproduce the crash. I'll rework the regression test based on the reduced reproducer in dtcxzyw/llvm-autoreduce#255 so it directly exercises the failing path.

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