[llvm] [llvm][CodeGen] Add a new software pipeliner 'Window Scheduler' (PR #84443)

[Hua Tian via llvm-commits]

huaatian wrote:

Does anyone have any more comments? We really hope that this algorithm can be merged into the mainline so that other DSA developers can use it.
ping at all

https://github.com/llvm/llvm-project/pull/84443