Changeset 261440 in webkit

Timestamp:

May 9, 2020 3:29:50 PM (4 years ago)

Author:

Darin Adler

Message:

Add iterator checking to ListHashSet
​https://bugs.webkit.org/show_bug.cgi?id=211669

Reviewed by Anders Carlsson.

HashSet and HashMap have iterator checking in debug builds.
Add similar checking to ListHashSet, controlled by the same
macro, CHECK_HASHTABLE_ITERATORS. Use WeakPtr to make the
implementation simple.

• wtf/ListHashSet.h: Make ListHashSet and ListHashSetNode derive

from CanMakeWeakPtr. Add m_weakSet and m_weakPosition members to
ListHashSetConstIterator, and assert their values at the appropriate
times so we will get a breakpoint or crash.

Location:

trunk/Source/WTF

Files:

• ChangeLog (modified) (1 diff)
• wtf/ListHashSet.h (modified) (9 diffs)

trunk/Source/WTF/ChangeLog

@@ +1 @@
+2020-05-09  Darin Adler  <darin@apple.com>
+
+        Add iterator checking to ListHashSet
+        https://bugs.webkit.org/show_bug.cgi?id=211669
+
+        Reviewed by Anders Carlsson.
+
+        HashSet and HashMap have iterator checking in debug builds.
+        Add similar checking to ListHashSet, controlled by the same
+        macro, CHECK_HASHTABLE_ITERATORS. Use WeakPtr to make the
+        implementation simple.
+
+        * wtf/ListHashSet.h: Make ListHashSet and ListHashSetNode derive
+        from CanMakeWeakPtr. Add m_weakSet and m_weakPosition members to
+        ListHashSetConstIterator, and assert their values at the appropriate
+        times so we will get a breakpoint or crash.
+
 2020-05-08  Darin Adler  <darin@apple.com>
 

trunk/Source/WTF/wtf/ListHashSet.h

@@ -24 +24 @@
 #include <wtf/HashSet.h>
 
+#if CHECK_HASHTABLE_ITERATORS
+#include <wtf/WeakPtr.h>
+#endif
+
 namespace WTF {
 
@@ -46 +50 @@
 template<typename HashArg> struct ListHashSetTranslator;
 
-template<typename ValueArg, typename HashArg = typename DefaultHash<ValueArg>::Hash> class ListHashSet final {
+template<typename ValueArg, typename HashArg = typename DefaultHash<ValueArg>::Hash> class ListHashSet final
+#if CHECK_HASHTABLE_ITERATORS
+    : public CanMakeWeakPtr<ListHashSet<ValueArg, HashArg>>
+#endif
+{
     WTF_MAKE_FAST_ALLOCATED;
 private:
@@ -165 +173 @@
 };
 
-template<typename ValueArg> struct ListHashSetNode {
-    WTF_MAKE_FAST_ALLOCATED;
-public:
-    template<typename T>
-    ListHashSetNode(T&& value)
+template<typename ValueArg> struct ListHashSetNode
+#if CHECK_HASHTABLE_ITERATORS
+    : CanMakeWeakPtr<ListHashSetNode<ValueArg>>
+#endif
+{
+    WTF_MAKE_STRUCT_FAST_ALLOCATED;
+
+    template<typename T> ListHashSetNode(T&& value)
         : m_value(std::forward<T>(value))
     {
@@ -248 +259 @@
         : m_set(set)
         , m_position(position)
+#if CHECK_HASHTABLE_ITERATORS
+        , m_weakSet(makeWeakPtr(set))
+        , m_weakPosition(makeWeakPtr(position))
+#endif
     {
     }
@@ -264 +279 @@
     const ValueType* get() const
     {
+#if CHECK_HASHTABLE_ITERATORS
+        ASSERT(m_weakPosition);
+#endif
         return std::addressof(m_position->m_value);
     }
@@ -272 +290 @@
     const_iterator& operator++()
     {
+#if CHECK_HASHTABLE_ITERATORS
+        ASSERT(m_weakPosition);
+#endif
         ASSERT(m_position);
         m_position = m_position->m_next;
+#if CHECK_HASHTABLE_ITERATORS
+        m_weakPosition = makeWeakPtr(m_position);
+#endif
         return *this;
     }
@@ -281 +305 @@
     const_iterator& operator--()
     {
+#if CHECK_HASHTABLE_ITERATORS
+        ASSERT(m_weakSet);
+        m_weakPosition.get();
+#endif
         ASSERT(m_position != m_set->m_head);
         if (!m_position)
@@ -286 +314 @@
         else
             m_position = m_position->m_prev;
+#if CHECK_HASHTABLE_ITERATORS
+        m_weakPosition = makeWeakPtr(m_position);
+#endif
         return *this;
     }
@@ -304 +335 @@
     Node* node() { return m_position; }
 
-    const ListHashSetType* m_set;
-    Node* m_position;
+    const ListHashSetType* m_set { nullptr };
+    Node* m_position { nullptr };
+#if CHECK_HASHTABLE_ITERATORS
+    WeakPtr<const ListHashSetType> m_weakSet;
+    WeakPtr<Node> m_weakPosition;
+#endif
 };