[PATCH] D124646: [SCEV] Support modelling of same base pointer `select`s in more complex than most trivial cases (when there is a base variable offset)

[Roman Lebedev via Phabricator via llvm-commits]

lebedev.ri created this revision.
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`umin_seq` `select` modelling requires that one of the hands of the select must be a constant.
After we remove pointer base, in all but most trivial cases,
there will likely be some other offset between the base and the selected-between pointers,
and if both of them happen to have some variable offset, we fail,
even if they have *the same* variable offset.

Instead, we should try to factor it out, perhaps that leaves us with a constant in one hand.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D124646

Files:
  llvm/lib/Analysis/ScalarEvolution.cpp
  llvm/test/Analysis/ScalarEvolution/pointer-select.ll

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