[all-commits] [llvm/llvm-project] 5c75c2: [LV] Forget LCSSA phi with new pred before other S...

[Florian Hahn via All-commits]

  Branch: refs/heads/release/20.x
  Home:   https://github.com/llvm/llvm-project
  Commit: 5c75c290f87aacd2227619748ccb0ffd4b578ea4
      https://github.com/llvm/llvm-project/commit/5c75c290f87aacd2227619748ccb0ffd4b578ea4
  Author: Florian Hahn <flo at fhahn.com>
  Date:   2025-02-10 (Mon, 10 Feb 2025)

  Changed paths:
    M llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
    A llvm/test/Transforms/LoopVectorize/invalidate-scev-at-scope-after-vectorization.ll

  Log Message:
  -----------
  [LV] Forget LCSSA phi with new pred before other SCEV invalidation. (#119897)

`forgetLcssaPhiWithNewPredecessor` performs additional invalidation if
there is an existing SCEV for the phi, but earlier
`forgetBlockAndLoopDispositions` or `forgetLoop` may already invalidate
the SCEV for the phi.

Change the order to first call `forgetLcssaPhiWithNewPredecessor` to
ensure it runs before its SCEV gets invalidated too eagerly.

Fixes https://github.com/llvm/llvm-project/issues/119665.

PR: https://github.com/llvm/llvm-project/pull/119897
(cherry picked from commit 3706dfef660097f24fb5efbac0d7f14b424492ed)



To unsubscribe from these emails, change your notification settings at https://github.com/llvm/llvm-project/settings/notifications