llvm-project

a5e388de - [GlobalISel] Fold Add Shift combine from SelectionDAG (#177371)

[GlobalISel] Fold Add Shift combine from SelectionDAG (#177371) This PR adds the combine rule `fold (add x, shl(0 - y, n)) -> sub(x, shl(y, n))` to GlobalISel, corresponding to an existing SelectionDAG combine in [DAGCombiner::visitADDLikeCommutative](https://github.com/llvm/llvm-project/blame/fcba3040107944604904aeb146c26ec0628160f4/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp#L3367). Co-authored-by: Sarah Kuhn <sarahlinhkuhn@gmail.com> --------- Co-authored-by: Sarah Kuhn <sarahlinhkuhn@gmail.com> Co-authored-by: Luisa Cicolini <48860705+luisacicolini@users.noreply.github.com>