Method WriteCollection

be/src/runtime/raw-value.cc:292–330

template <bool COLLECT_VAR_LEN_VALS>
void RawValue::WriteCollection(const void* value, Tuple* tuple,
    const SlotDescriptor* slot_desc, MemPool* pool, vector<StringValue*>* string_values,
    vector<pair<CollectionValue*, int64_t>>* collection_values) {
  DCHECK(slot_desc->type().IsCollectionType());

  void* dst = tuple->GetSlot(slot_desc->tuple_offset());

  const CollectionValue* src = reinterpret_cast<const CollectionValue*>(value);
  CollectionValue* dest = reinterpret_cast<CollectionValue*>(dst);
  dest->num_tuples = src->num_tuples;

  int64_t byte_size = dest->ByteSize(*slot_desc->children_tuple_descriptor());
  if (pool != nullptr) {
    // If 'dest' and 'src' point to the same address, assigning the address of the newly
    // allocated buffer to 'dest->ptr' will also overwrite 'src->ptr', and the memcpy will
    // be from the destination to the destination.
    DCHECK_NE(dest, src);
    // Note: if this changes to TryAllocate(), SlotDescriptor::CodegenWriteToSlot() will
    // need to reflect this change as well (the codegen'd Allocate() call is actually
    // generated in SlotDescriptor::CodegenWriteStringOrCollectionToSlot()).
    dest->ptr = reinterpret_cast<uint8_t*>(pool->Allocate(byte_size));
    Ubsan::MemCpy(dest->ptr, src->ptr, byte_size);
  } else {
    dest->ptr = src->ptr;
  }

  // We only need to recurse if this is a deep copy (pool != nullptr) OR if we collect
  // var-len values.
  if (pool != nullptr || COLLECT_VAR_LEN_VALS) {
    WriteCollectionChildren<COLLECT_VAR_LEN_VALS>(*dest, *src, *slot_desc, pool,
        string_values, collection_values);
  }

  if (COLLECT_VAR_LEN_VALS) {
    DCHECK(string_values != nullptr);
    DCHECK(collection_values != nullptr);
    collection_values->push_back(std::make_pair(dest, byte_size));
  }
}

template <bool COLLECT_VAR_LEN_VALS>
void RawValue::WriteCollectionChildren(const CollectionValue& dest,