[llvm] Reland "[LoopVectorizer] Add support for chaining partial reductions #120272" (PR #124282)

[Nicholas Guy via llvm-commits]

NickGuy-Arm wrote:

Thanks @mikaelholmen I've opened a PR at https://github.com/llvm/llvm-project/pull/136680 to fix this.


https://github.com/llvm/llvm-project/pull/124282