[llvm] [GlobalISel] Fold Add Shift combine from SelectionDAG (PR #177371)

[Osman Yasar via llvm-commits]

osmanyasar05 wrote:

I added hasOneUse checks for the inner `(0-B)` and the `shl (0-B, C)` operations, also added a new test case to ensure the rewrite does not fire when there are multiple uses. @arsenm 

https://github.com/llvm/llvm-project/pull/177371