[all-commits] [llvm/llvm-project] 2c7d5f: [SCEV] Generalize implication when signedness of F...

[Max Kazantsev via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 2c7d5fbc9ebf914f90acad8534289ea01e899ec8
      https://github.com/llvm/llvm-project/commit/2c7d5fbc9ebf914f90acad8534289ea01e899ec8
  Author: Max Kazantsev <mkazantsev at azul.com>
  Date:   2021-09-21 (Tue, 21 Sep 2021)

  Changed paths:
    M llvm/lib/Analysis/ScalarEvolution.cpp
    M llvm/test/Transforms/IndVarSimplify/negative_ranges.ll

  Log Message:
  -----------
  [SCEV] Generalize implication when signedness of FoundPred doesn't matter

The implication logic for two values that are both negative or non-negative
says that it doesn't matter whether their predicate is signed and unsigned,
but only flips unsigned into signed for further inference. This patch adds
support for flipping a signed predicate into unsigned as well.

Differential Revision: https://reviews.llvm.org/D109959
Reviewed By: nikic