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Fixed code review issues

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This commit is contained in:
Maksim Kita 2022-08-08 14:54:11 +02:00
parent 59db59fe83
commit a9c8e13344
1 changed files with 10 additions and 31 deletions
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41
src/Parsers/IAST.cpp
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@ -32,7 +32,7 @@ IAST::~IAST()
* Each ASTPtr child contains pointer to next child to delete.
*/
ASTPtr delete_list_head_holder = nullptr;
bool delete_directly = next_to_delete_list_head == nullptr;
const bool delete_directly = next_to_delete_list_head == nullptr;
ASTPtr & delete_list_head_reference = next_to_delete_list_head ? *next_to_delete_list_head : delete_list_head_holder;
/// Move children into intrusive list
@ -65,7 +65,14 @@ IAST::~IAST()
while (delete_list_head_reference)
{
auto next_node_to_delete = std::move(delete_list_head_reference->next_to_delete);
/** Extract child to delete from current list head.
* Child will be destroyed at the end of scope.
*/
ASTPtr child_to_delete;
child_to_delete.swap(delete_list_head_reference);
/// Update list head
delete_list_head_reference = std::move(child_to_delete->next_to_delete);
/** Pass list head into child before destruction.
* It is important to properly handle cases where subclass has member same as one of its children.
@ -79,35 +86,7 @@ IAST::~IAST()
* If we try to move child to delete children into list before subclasses desruction,
* first child use count will be 2.
*/
{
ASTPtr child_to_delete;
child_to_delete.swap(delete_list_head_reference);
child_to_delete->next_to_delete_list_head = &delete_list_head_reference;
}
/** Here we have 2 cases:
* 1. Child during deletion does not move any node into list, then just replace current head with next node to delete.
* 2. Child during deletion moved some nodes into list, then iterate list and add next to delete node in list tail.
*/
if (delete_list_head_reference == nullptr)
{
delete_list_head_reference = std::move(next_node_to_delete);
}
else
{
ASTPtr delete_list_tail = delete_list_head_reference;
while (delete_list_tail)
{
if (delete_list_tail->next_to_delete == nullptr)
{
delete_list_tail->next_to_delete = std::move(next_node_to_delete);
break;
}
delete_list_tail = delete_list_tail->next_to_delete;
}
}
child_to_delete->next_to_delete_list_head = &delete_list_head_reference;
}
}