[PATCH] D124419: [InstCombine] try to fold icmp with mismatched extended operands

[Sanjay Patel via Phabricator via llvm-commits]

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If a value is known to be non-negative and zexted, that's the same thing as sexted.

So for the purpose of looking past the casts with an icmp, treat it as if it was a sext:
https://alive2.llvm.org/ce/z/_BDsGV

This is necessary, but not enough to solve the motivating problem:
https://github.com/llvm/llvm-project/issues/55013


https://reviews.llvm.org/D124419

Files:
  llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp
  llvm/lib/Transforms/InstCombine/InstCombineInternal.h
  llvm/test/Transforms/InstCombine/icmp-ext-ext.ll

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