[llvm-branch-commits] [llvm] [VPlan] Scalarize to first-lane-only directly on VPlan (PR #184267)

[Andrei Elovikov via llvm-branch-commits]

================
@@ -6395,3 +6395,68 @@ void VPlanTransforms::makeMemOpWideningDecisions(
                              return ReplaceWith(VPI, Recipe);
                            });
 }
+
+void VPlanTransforms::makeScalarizationDecisions(
+    VPlan &Plan, VFRange &Range, VPRecipeBuilder &RecipeBuilder) {
+  if (LoopVectorizationPlanner::getDecisionAndClampRange(
+          [&](ElementCount VF) { return VF.isScalar(); }, Range))
----------------
eas wrote:

```c++
if (LoopVectorizationPlanner::getDecisionAndClampRange(
        Predicate: std::mem_fn(pm: &ElementCount::isScalar), &: Range))
  return;
```

would work, but I don't think it's more readable than a lambda.

https://github.com/llvm/llvm-project/pull/184267