1 files changed, 31 insertions, 37 deletions

diff --git a/src/shared_string.hh b/src/shared_string.hh
index ffd8bf04..b3906ea3 100644
--- a/src/shared_string.hh
+++ b/src/shared_string.hh
@@ -13,61 +13,55 @@ namespace Kakoune
 
 struct StringData : UseMemoryDomain<MemoryDomain::SharedString>
 {
-    int refcount;
-    int length;
+    uint32_t refcount;
+    const int length;
 
-    StringData(int ref, int len) : refcount(ref), length(len) {}
-
-    [[gnu::always_inline]]
-    char* data() { return reinterpret_cast<char*>(this + 1); }
     [[gnu::always_inline]]
     const char* data() const { return reinterpret_cast<const char*>(this + 1); }
     [[gnu::always_inline]]
     StringView strview() const { return {data(), length}; }
 
+private:
+    StringData(int len) : refcount(0), length(len) {}
+
+    static constexpr uint32_t interned_flag = 1 << 31;
+    static constexpr uint32_t refcount_mask = ~interned_flag;
+
     struct PtrPolicy
     {
         static void inc_ref(StringData* r, void*) noexcept { ++r->refcount; }
-        static void dec_ref(StringData* r, void*) noexcept { if (--r->refcount == 0) destroy(r); }
+        static void dec_ref(StringData* r, void*) noexcept
+        {
+            if ((--r->refcount & refcount_mask) == 0)
+            {
+                if (r->refcount & interned_flag)
+                    Registry::instance().remove(r->strview());
+                StringData::operator delete(r, sizeof(StringData) + r->length + 1);
+            }
+        }
         static void ptr_moved(StringData*, void*, void*) noexcept {}
     };
 
-    static RefPtr<StringData, PtrPolicy> create(ArrayView<const StringView> strs)
-    {
-        const int len = std::accumulate(strs.begin(), strs.end(), 0,
-                                        [](int l, StringView s)
-                                        { return l + (int)s.length(); });
-        void* ptr = StringData::operator new(sizeof(StringData) + len + 1);
-        auto* res = new (ptr) StringData(0, len);
-        auto* data = res->data();
-        for (auto& str : strs)
-        {
-            memcpy(data, str.begin(), (size_t)str.length());
-            data += (int)str.length();
-        }
-        res->data()[len] = 0;
-        return RefPtr<StringData, PtrPolicy>{res};
-    }
+public:
+    using Ptr = RefPtr<StringData, PtrPolicy>;
 
-    static void destroy(StringData* s)
+    class Registry : public Singleton<Registry>
     {
-        StringData::operator delete(s, sizeof(StringData) + s->length + 1);
-    }
-};
+    public:
+        void debug_stats() const;
+        Ptr intern(StringView str);
+        void remove(StringView str);
 
-using StringDataPtr = RefPtr<StringData, StringData::PtrPolicy>;
-
-class StringRegistry : public Singleton<StringRegistry>
-{
-public:
-    void debug_stats() const;
-    StringDataPtr intern(StringView str);
-    void purge_unused();
+    private:
+        UnorderedMap<StringView, StringData*, MemoryDomain::SharedString> m_strings;
+    };
 
-private:
-    UnorderedMap<StringView, StringDataPtr, MemoryDomain::SharedString> m_strings;
+    static Ptr create(ArrayView<const StringView> strs);
 };
 
+using StringDataPtr = StringData::Ptr;
+using StringRegistry = StringData::Registry;
+
 inline StringDataPtr intern(StringView str)
 {
     return StringRegistry::instance().intern(str);