SharedPtr: Remove explicit detached bool

`detach()` now fully releases the object, resulting in memory and performance savings. Profile before (compiling bootstrap 4): ``` flat flat% sum% cum cum% 24651348 6.97% 6.97% 24651348 6.97% [[kernel.kallsyms]] 20746241 5.87% 12.84% 20746241 5.87% Sass::SharedPtr::decRefCount 18401663 5.20% 18.04% 20420896 5.78% __libc_malloc 15205959 4.30% 22.34% 15205959 4.30% [libc-2.27.so] 12974307 3.67% 26.01% 14070189 3.98% _int_malloc 10958857 3.10% 29.11% 10958857 3.10% Sass::SharedPtr::incRefCount 9837672 2.78% 31.89% 18433250 5.21% cfree 8770779 2.48% 34.37% 8770779 2.48% Sass::Inspect::operator() ``` Profile after: ``` flat flat% sum% cum cum% 28346546 7.94% 7.94% 28346546 7.94% [[kernel.kallsyms]] 20920665 5.86% 13.80% 20920665 5.86% [libc-2.27.so] 13540151 3.79% 17.60% 14637507 4.10% __libc_malloc 13091487 3.67% 21.26% 13091487 3.67% Sass::SharedPtr::incRefCount 9864675 2.76% 24.03% 9864675 2.76% Sass::SharedPtr::decRefCount 8763387 2.46% 26.48% 8763387 2.46% _int_malloc 7676121 2.15% 28.63% 7676121 2.15% std::vector::_M_realloc_insert 6578211 1.84% 30.48% 6578211 1.84% __dynamic_cast ```
nschonni · Nov 14, 2018 · 2ebf465 · 2ebf465
1 parent 5baf0fa
commit 2ebf465
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Showing 2 changed files with 10 additions and 18 deletions.
diff --git a/src/memory/SharedPtr.cpp b/src/memory/SharedPtr.cpp
@@ -32,12 +32,11 @@ namespace Sass {
   bool SharedObj::taint = false;
 
   SharedObj::SharedObj()
-  : detached(false)
+  : refcounter(0)
     #ifdef DEBUG_SHARED_PTR
     , dbg(false)
     #endif
   {
-    refcounter = 0;
     #ifdef DEBUG_SHARED_PTR
       if (taint) all.push_back(this);
     #endif
@@ -63,17 +62,14 @@ namespace Sass {
           // AST_Node_Ptr ast = dynamic_cast<AST_Node*>(node);
           if (node->dbg) std::cerr << "DELETE NODE " << node << "\n";
         #endif
-        if (!node->detached) {
-          delete(node);
-        }
+        delete(node);
       }
     }
   }
 
   void SharedPtr::incRefCount() {
     if (node) {
       ++ node->refcounter;
-      node->detached = false;
       #ifdef DEBUG_SHARED_PTR
         if (node->dbg) {
           std::cerr << "+ " << node << " X " << node->refcounter << " (" << this << ") " << "\n";
@@ -111,4 +107,4 @@ namespace Sass {
     incRefCount();
   }
 
-}
+}
diff --git a/src/memory/SharedPtr.hpp b/src/memory/SharedPtr.hpp
@@ -49,8 +49,6 @@ namespace Sass {
     #endif
     static bool taint;
     long refcounter;
-    // long refcount;
-    bool detached;
     #ifdef DEBUG_SHARED_PTR
       bool dbg;
     #endif
@@ -82,7 +80,7 @@ namespace Sass {
     virtual const std::string to_string() const = 0;
 
     virtual ~SharedObj();
-    long getRefCount() {
+    long getRefCount() const {
       return refcounter;
     }
   };
@@ -123,11 +121,10 @@ namespace Sass {
     bool isNull () const {
       return node == NULL;
     };
-    SharedObj* detach() const {
-      if (node) {
-        node->detached = true;
-      }
-      return node;
+    SharedObj* detach() {
+      SharedObj* result = node;
+      node = NULL;
+      return result;
     };
     operator bool() const {
       return node != NULL;
@@ -197,8 +194,7 @@ namespace Sass {
     T* ptr () const {
       return static_cast<T*>(this->obj());
     };
-    T* detach() const {
-      if (this->obj() == NULL) return NULL;
+    T* detach() {
       return static_cast<T*>(SharedPtr::detach());
     }
     bool isNull() const {
@@ -214,4 +210,4 @@ namespace Sass {
 
 }
 
-#endif
+#endif