Review nits

Author: JonPsson1

llvm/include/llvm/Analysis/TargetTransformInfo.h

@@ -913,7 +913,7 @@ class TargetTransformInfo {
   /// Insert is true.
   InstructionCost getScalarizationOverhead(
       VectorType *Ty, const APInt &DemandedElts, bool Insert, bool Extract,
-      TTI::TargetCostKind CostKind, ArrayRef<Value *> VL = std::nullopt) const;
+      TTI::TargetCostKind CostKind, ArrayRef<Value *> VL = {}) const;
 
   /// Estimate the overhead of scalarizing an instructions unique
   /// non-constant operands. The (potentially vector) types to use for each of
@@ -2004,7 +2004,7 @@ class TargetTransformInfo::Concept {
   virtual InstructionCost
   getScalarizationOverhead(VectorType *Ty, const APInt &DemandedElts,
                            bool Insert, bool Extract, TargetCostKind CostKind,
-                           ArrayRef<Value *> VL = std::nullopt) = 0;
+                           ArrayRef<Value *> VL = {}) = 0;
   virtual InstructionCost
   getOperandsScalarizationOverhead(ArrayRef<const Value *> Args,
                                    ArrayRef<Type *> Tys,
@@ -2585,7 +2585,7 @@ class TargetTransformInfo::Model final : public TargetTransformInfo::Concept {
   InstructionCost
   getScalarizationOverhead(VectorType *Ty, const APInt &DemandedElts,
                            bool Insert, bool Extract, TargetCostKind CostKind,
-                           ArrayRef<Value *> VL = std::nullopt) override {
+                           ArrayRef<Value *> VL = {}) override {
     return Impl.getScalarizationOverhead(Ty, DemandedElts, Insert, Extract,
                                          CostKind, VL);
   }

llvm/include/llvm/Analysis/TargetTransformInfoImpl.h

@@ -403,7 +403,7 @@ class TargetTransformInfoImplBase {
 
   InstructionCost getScalarizationOverhead(
       VectorType *Ty, const APInt &DemandedElts, bool Insert, bool Extract,
-      TTI::TargetCostKind CostKind, ArrayRef<Value *> VL = std::nullopt) const {
+      TTI::TargetCostKind CostKind, ArrayRef<Value *> VL = {}) const {
     return 0;
   }
 

llvm/include/llvm/CodeGen/BasicTTIImpl.h

@@ -779,17 +779,15 @@ class BasicTTIImplBase : public TargetTransformInfoImplCRTPBase<T> {
   /// extracted from vectors.
   InstructionCost getScalarizationOverhead(
       VectorType *InTy, const APInt &DemandedElts, bool Insert, bool Extract,
-      TTI::TargetCostKind CostKind, ArrayRef<Value *> VL = std::nullopt) {
-    assert((VL.empty() ||
-            VL.size() == cast<FixedVectorType>(InTy)->getNumElements()) &&
-           "Type does not match the values.");
+      TTI::TargetCostKind CostKind, ArrayRef<Value *> VL = {}) {
     /// FIXME: a bitfield is not a reasonable abstraction for talking about
     /// which elements are needed from a scalable vector
     if (isa<ScalableVectorType>(InTy))
       return InstructionCost::getInvalid();
     auto *Ty = cast<FixedVectorType>(InTy);
 
     assert(DemandedElts.getBitWidth() == Ty->getNumElements() &&
+           (VL.empty() || VL.size() == Ty->getNumElements()) &&
            "Vector size mismatch");
 
     InstructionCost Cost = 0;

llvm/lib/Target/AArch64/AArch64TargetTransformInfo.h

@@ -424,7 +424,7 @@ class AArch64TTIImpl : public BasicTTIImplBase<AArch64TTIImpl> {
                                            const APInt &DemandedElts,
                                            bool Insert, bool Extract,
                                            TTI::TargetCostKind CostKind,
-                                           ArrayRef<Value *> VL = std::nullopt);
+                                           ArrayRef<Value *> VL = {});
 
   /// Return the cost of the scaling factor used in the addressing
   /// mode represented by AM for this target, for a load/store

llvm/lib/Target/RISCV/RISCVTargetTransformInfo.h

@@ -150,7 +150,7 @@ class RISCVTTIImpl : public BasicTTIImplBase<RISCVTTIImpl> {
                                            const APInt &DemandedElts,
                                            bool Insert, bool Extract,
                                            TTI::TargetCostKind CostKind,
-                                           ArrayRef<Value *> VL = std::nullopt);
+                                           ArrayRef<Value *> VL = {});
 
   InstructionCost getIntrinsicInstrCost(const IntrinsicCostAttributes &ICA,
                                         TTI::TargetCostKind CostKind);

llvm/lib/Target/SystemZ/SystemZTargetTransformInfo.h

@@ -85,7 +85,7 @@ class SystemZTTIImpl : public BasicTTIImplBase<SystemZTTIImpl> {
                                            const APInt &DemandedElts,
                                            bool Insert, bool Extract,
                                            TTI::TargetCostKind CostKind,
-                                           ArrayRef<Value *> VL = std::nullopt);
+                                           ArrayRef<Value *> VL = {});
   bool supportsEfficientVectorElementLoadStore() { return true; }
   bool enableInterleavedAccessVectorization() { return true; }
 

llvm/lib/Target/X86/X86TargetTransformInfo.h

@@ -170,7 +170,7 @@ class X86TTIImpl : public BasicTTIImplBase<X86TTIImpl> {
                                            const APInt &DemandedElts,
                                            bool Insert, bool Extract,
                                            TTI::TargetCostKind CostKind,
-                                           ArrayRef<Value *> VL = std::nullopt);
+                                           ArrayRef<Value *> VL = {});
   InstructionCost getReplicationShuffleCost(Type *EltTy, int ReplicationFactor,
                                             int VF,
                                             const APInt &DemandedDstElts,