[all-commits] [llvm/llvm-project] b8ac19: [SCEV] Limited support for unsigned preds in isImp...

[max-azul via All-commits]

  Branch: refs/heads/master
  Home:   https://github.com/llvm/llvm-project
  Commit: b8ac19cf1cca5faec8b4404bb0f666cb63c9e1de
      https://github.com/llvm/llvm-project/commit/b8ac19cf1cca5faec8b4404bb0f666cb63c9e1de
  Author: Max Kazantsev <mkazantsev at azul.com>
  Date:   2020-10-02 (Fri, 02 Oct 2020)

  Changed paths:
    M llvm/lib/Analysis/ScalarEvolution.cpp
    M llvm/unittests/Analysis/ScalarEvolutionTest.cpp

  Log Message:
  -----------
  [SCEV] Limited support for unsigned preds in isImpliedViaOperations

The logic there only considers `SLT/SGT` predicates. We can use the same logic
for proving `ULT/UGT` predicates if all involved values are non-negative.

Adding full-scale support for unsigned might be challenging because of code amount,
so we can consider this in the future.

Differential Revision: https://reviews.llvm.org/D88087
Reviewed By: reames