[all-commits] [llvm/llvm-project] ada219: [NFC][IndVars] Add test that caused D108043 to be ...

[Roman Lebedev via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: ada219b13a2debc94cb252feb0dd987ef9290126
      https://github.com/llvm/llvm-project/commit/ada219b13a2debc94cb252feb0dd987ef9290126
  Author: Roman Lebedev <lebedev.ri at gmail.com>
  Date:   2021-08-30 (Mon, 30 Aug 2021)

  Changed paths:
    A llvm/test/Transforms/IndVarSimplify/D108043.ll

  Log Message:
  -----------
  [NFC][IndVars] Add test that caused D108043 to be reverted

We currently don't simplify anything here, but we can.


  Commit: 7b0d59da9af4bf4eb8342cac579e42a818ac1ae7
      https://github.com/llvm/llvm-project/commit/7b0d59da9af4bf4eb8342cac579e42a818ac1ae7
  Author: Roman Lebedev <lebedev.ri at gmail.com>
  Date:   2021-08-30 (Mon, 30 Aug 2021)

  Changed paths:
    M llvm/lib/Transforms/Utils/LoopUtils.cpp
    M llvm/test/Transforms/IndVarSimplify/D108043.ll

  Log Message:
  -----------
  [IndVars] Drop check for the validity of rewrite

`isValidRewrite()` checks that the both the original SCEV,
and the rewrite SCEV have the same base pointer.
I //believe//, after all the recent SCEV improvements,
this invariant is already enforced by SCEV itself.

I originally tried changing it into an assert in D108043,
but that showed that it triggers on e.g. https://reviews.llvm.org/D108043#2946621,
where SCEV manages to forward the store to load,
test added.

Reviewed By: nikic

Differential Revision: https://reviews.llvm.org/D108655


Compare: https://github.com/llvm/llvm-project/compare/0a1d80d56e6a...7b0d59da9af4