[all-commits] [llvm/llvm-project] 426297: [DSE] Add test case showing bug PR52774.

[Marianne Mailhot-Sarrasin via All-commits]

  Branch: refs/heads/release/13.x
  Home:   https://github.com/llvm/llvm-project
  Commit: 426297cce9d5138e6085d51c66a8a1dc4dd23b17
      https://github.com/llvm/llvm-project/commit/426297cce9d5138e6085d51c66a8a1dc4dd23b17
  Author: Marianne Mailhot-Sarrasin <marianne.ms.qc at gmail.com>
  Date:   2022-01-06 (Thu, 06 Jan 2022)

  Changed paths:
    A llvm/test/Transforms/DeadStoreElimination/store-after-loop.ll

  Log Message:
  -----------
  [DSE] Add test case showing bug PR52774.

Pre-commiting the test case before the bug fix.

Reviewed by: Florian Hahn

Differential revision: https://reviews.llvm.org/D115965

(cherry picked from commit df590567aa435211dea1f306b55b8d4ba92ddbb1)


  Commit: 33f7aa65f5d77bdec6a528af65ff0fa9033370c2
      https://github.com/llvm/llvm-project/commit/33f7aa65f5d77bdec6a528af65ff0fa9033370c2
  Author: Marianne Mailhot-Sarrasin <marianne.ms.qc at gmail.com>
  Date:   2022-01-06 (Thu, 06 Jan 2022)

  Changed paths:
    M llvm/lib/Transforms/Scalar/DeadStoreElimination.cpp
    M llvm/test/Transforms/DeadStoreElimination/store-after-loop.ll

  Log Message:
  -----------
  [DSE] Fix invalid removal of store instruction

Fix handling of alloc-like instructions in isGuaranteedLoopInvariant(). It was not valid when the 'KillingDef' was outside of the loop, while the 'CurrentDef' was inside the loop. In that case, the 'KillingDef' only overwrites the definition from the last iteration of the loop, and not the ones of all iterations. Therefor it does not make the 'CurrentDef' to be dead, and must not remove it.

Fixing issue : https://github.com/llvm/llvm-project/issues/52774

Reviewed by: Florian Hahn

Differential revision: https://reviews.llvm.org/D115965

(cherry picked from commit 90d1786ba0c233456b7785fe4b93eca835d56028)


Compare: https://github.com/llvm/llvm-project/compare/0d44201451f0...33f7aa65f5d7