[all-commits] [llvm/llvm-project] faa631: [LSV] Improve chain splitting in some corner cases.

[Artem Belevich via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: faa631f939e43260deb707cffbeda4cda341f350
      https://github.com/llvm/llvm-project/commit/faa631f939e43260deb707cffbeda4cda341f350
  Author: Artem Belevich <tra at google.com>
  Date:   2023-04-17 (Mon, 17 Apr 2023)

  Changed paths:
    M llvm/lib/Transforms/Vectorize/LoadStoreVectorizer.cpp
    A llvm/test/Transforms/LoadStoreVectorizer/NVPTX/vectorize_i8.ll

  Log Message:
  -----------
  [LSV] Improve chain splitting in some corner cases.

Currently we happen to split a chain of 12xi8 accesses into 6xi8 + 6xi8, which
produces rather suboptimal code.

This change attempts to split-off non-multiples of 4bytes at the end and if that
does not work, splits on the smaller power-of-2 boundary.

Differential Revision: https://reviews.llvm.org/D147976