[llvm] [CostModel] Add type-based cost model for get.active.lane.mask intrinsic (PR #130132)

[Ricardo Jesus via llvm-commits]

================
@@ -1987,25 +2010,8 @@ class BasicTTIImplBase : public TargetTransformInfoImplCRTPBase<T> {
       return Cost;
     }
     case Intrinsic::get_active_lane_mask: {
-      EVT ResVT = getTLI()->getValueType(DL, RetTy, true);
-      EVT ArgType = getTLI()->getValueType(DL, ICA.getArgTypes()[0], true);
-
-      // If we're not expanding the intrinsic then we assume this is cheap
-      // to implement.
-      if (!getTLI()->shouldExpandGetActiveLaneMask(ResVT, ArgType)) {
-        return getTypeLegalizationCost(RetTy).first;
-      }
-
-      // Create the expanded types that will be used to calculate the uadd_sat
-      // operation.
-      Type *ExpRetTy = VectorType::get(
-          ICA.getArgTypes()[0], cast<VectorType>(RetTy)->getElementCount());
-      IntrinsicCostAttributes Attrs(Intrinsic::uadd_sat, ExpRetTy, {}, FMF);
-      InstructionCost Cost =
-          thisT()->getTypeBasedIntrinsicInstrCost(Attrs, CostKind);
-      Cost += thisT()->getCmpSelInstrCost(BinaryOperator::ICmp, ExpRetTy, RetTy,
-                                          CmpInst::ICMP_ULT, CostKind);
-      return Cost;
+      return thisT()->getActiveLaneMaskCost(RetTy, ICA.getArgTypes()[0],
+                                            CostKind);
----------------
rj-jesus wrote:

Could this be
```
return thisT()->getTypeBasedIntrinsicInstrCost(ICA, CostKind);
```
so that `getActiveLaneMaskCost` could be moved inline to `getTypeBasedIntrinsicInstrCost`? That's what we did for `experimental_vector_match`.

 If we did this, we could probably also group the `case` blocks of the two intrinsics and save an extra LOC. What do you think? :)

https://github.com/llvm/llvm-project/pull/130132