[all-commits] [llvm/llvm-project] 332477: [SLP] Improve gather tree nodes matching when user...

[Valery Dmitriev via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 3324776d9c043be1cd5df7d325e55067bf8eda73
      https://github.com/llvm/llvm-project/commit/3324776d9c043be1cd5df7d325e55067bf8eda73
  Author: Valery Dmitriev <valery.n.dmitriev at intel.com>
  Date:   2023-10-24 (Tue, 24 Oct 2023)

  Changed paths:
    M llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp
    M llvm/test/Transforms/SLPVectorizer/X86/delayed-gather-emission.ll
    M llvm/test/Transforms/SLPVectorizer/X86/matching-gather-nodes-phi-users.ll

  Log Message:
  -----------
  [SLP] Improve gather tree nodes matching when users are PHIs. (#70111)

This is re-commit of #69392 and also fixes issue #69670 which was
uncovered with the prior commit.
For delayed gather emission it may be incorrect to use stab instruction
as insertion point if it is a PHI operand. For that case insertion point
is adjusted to be at the end of block, ensuring that prior dependecy
vector code is emitted earlier.