[all-commits] [llvm/llvm-project] 93ccd7: [MLIR][Presburger] fix bug where Simplex::addZeroR...

[Arjun P via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 93ccd7c490ede05b5e8d004349c62d3eb9d032aa
      https://github.com/llvm/llvm-project/commit/93ccd7c490ede05b5e8d004349c62d3eb9d032aa
  Author: Arjun P <arjunpitchanathan at gmail.com>
  Date:   2022-03-22 (Tue, 22 Mar 2022)

  Changed paths:
    M mlir/lib/Analysis/Presburger/Simplex.cpp

  Log Message:
  -----------
  [MLIR][Presburger] fix bug where Simplex::addZeroRow was not undoable

Previously, an UndoLogEntry was added by addRow but not by addZeroRow. So
calling directly into addZeroRow, as LexSimplex::addCut does, was not an
undoable operation. In the current usage of addCut this could never
lead to an incorrect result, and addZeroRow is protected, so it is not
currently possible to add a regression test for this. This bug needs to be
fixed for the symbolic integer lexmin algorithm.

Reviewed By: Groverkss

Differential Revision: https://reviews.llvm.org/D122162