[llvm] [DAG] SDPatternMatch - add matchers for reassociatable binops (PR #119985)

[Ethan Kaji via llvm-commits]

Esan5 wrote:

I'm having trouble recreating the failing build on `windows-windows-x64`. From the logs it looks like tests are faling under `llvm/test/tools`, but when I run these with `llvm-lit llvm/test/tools`everything appears to be passing. Is there a compilation step I'm missing?

https://github.com/llvm/llvm-project/pull/119985