[all-commits] [llvm/llvm-project] 554870: [LoopUnrollAndJam] Avoid repeated instructions for...

[Danilo Carvalho Grael via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 55487079a9bb039103615a78500d1cdd4de474ab
      https://github.com/llvm/llvm-project/commit/55487079a9bb039103615a78500d1cdd4de474ab
  Author: Danilo C. Grael <dancgr at gmail.com>
  Date:   2021-04-15 (Thu, 15 Apr 2021)

  Changed paths:
    M llvm/lib/Transforms/Utils/LoopUnrollAndJam.cpp
    A llvm/test/Transforms/LoopUnrollAndJam/unroll-and-jam-many-instr.ll

  Log Message:
  -----------
  [LoopUnrollAndJam] Avoid repeated instructions for UAJ analysis

Avoid visiting repeated instructions for processHeaderPhiOperands as it can cause a scenario of endless loop. Test case is attached and can be ran with `opt -basic-aa -tbaa -loop-unroll-and-jam  -allow-unroll-and-jam -unroll-and-jam-count=4`.

Reviewed By: dmgreen

Differential Revision: https://reviews.llvm.org/D97407