llvm-project

07c085af - [VPlan] Add narrowToSingleScalarRecipe transform. (#139150)

[VPlan] Add narrowToSingleScalarRecipe transform. (#139150) Add a new convertToUniformRecipes transform which uses VPlan-based uniformity analysis to determine if wide recipes and replicate recipes can be converted to uniform recipes. There are a few places where we ad-hoc convert recipes to uniform recipes, which this transform will eventually replace. There are a few more generalizations required to do so which I plan to do as follow-ups. By converting the recipes to uniform recipes, we effectively materialize the information from the VPlan-based analysis. Note that there is one regression at the moment in SystemZ/pr47665.ll due to trivial constant folding opportunities in the input IR. This will be fixed by VPlan-based constant folding (https://github.com/llvm/llvm-project/pull/125365/) PR: https://github.com/llvm/llvm-project/pull/139150