Address review comments

Author: skachkov-sc

llvm/include/llvm/CodeGen/BasicTTIImpl.h

@@ -1472,8 +1472,10 @@ class BasicTTIImplBase : public TargetTransformInfoImplCRTPBase<T> {
   InstructionCost getExpandCompressMemoryOpCost(
       unsigned Opcode, Type *DataTy, bool VariableMask, Align Alignment,
       TTI::TargetCostKind CostKind, const Instruction *I = nullptr) {
+    // Treat expand load/compress store as gather/scatter operation.
+    // TODO: implement more precise cost estimation for these intrinsics.
     return getCommonMaskedMemoryOpCost(Opcode, DataTy, Alignment, VariableMask,
-                                       true, CostKind);
+                                       /*IsGatherScatter*/ true, CostKind);
   }
 
   InstructionCost getStridedMemoryOpCost(unsigned Opcode, Type *DataTy,

llvm/lib/Target/RISCV/RISCVTargetTransformInfo.cpp

@@ -862,7 +862,8 @@ InstructionCost RISCVTTIImpl::getExpandCompressMemoryOpCost(
   // vsetivli        zero, 8, e32, m2, ta, ma
   // viota.m v12, v0
   // vrgather.vv     v8, v10, v12, v0.t
-  auto MemOpCost = getMemoryOpCost(Opcode, DataTy, Alignment, 0, CostKind);
+  auto MemOpCost =
+      getMemoryOpCost(Opcode, DataTy, Alignment, /*AddressSpace*/ 0, CostKind);
   auto LT = getTypeLegalizationCost(DataTy);
   SmallVector<unsigned, 4> Opcodes{RISCV::VSETVLI};
   if (VariableMask)