Changeset 30042 in webkit

Timestamp:

Feb 6, 2008 9:53:53 AM (16 years ago)

Author:

ggaren@apple.com

Message:

Reviewed by Darin Adler.

PLT speedup related to <rdar://problem/5659272> REGRESSION: PLT .4%
slower due to r28884 (global variable symbol table optimization)

Tweaked RefCounted::deref() to be a little more efficient.

1% - 1.5% speedup on my machine. .7% speedup on Stephanie's machine.

• wtf/RefCounted.h: (WTF::RefCounted::deref): Don't modify m_refCount if we're just going to delete the object anyway. Also, use a simple == test, which might be faster than <= on some hardware.

Location:

trunk/JavaScriptCore

Files:

• ChangeLog (modified) (1 diff)
• wtf/RefCounted.h (modified) (1 diff)

trunk/JavaScriptCore/ChangeLog

@@ +1 @@
+2008-02-06  Geoffrey Garen  <ggaren@apple.com>
+
+        Reviewed by Darin Adler.
+
+        PLT speedup related to <rdar://problem/5659272> REGRESSION: PLT .4%
+        slower due to r28884 (global variable symbol table optimization)
+        
+        Tweaked RefCounted::deref() to be a little more efficient.
+
+        1% - 1.5% speedup on my machine. .7% speedup on Stephanie's machine.
+        
+        * wtf/RefCounted.h:
+        (WTF::RefCounted::deref): Don't modify m_refCount if we're just going
+        to delete the object anyway. Also, use a simple == test, which might be
+        faster than <= on some hardware.
+
 2008-02-06  Darin Adler  <darin@apple.com>
 

trunk/JavaScriptCore/wtf/RefCounted.h

@@ -46 +46 @@
     {
         ASSERT(!m_deletionHasBegun);
-        if (--m_refCount <= 0) {
+        if (m_refCount == 1) {
 #ifndef NDEBUG
             m_deletionHasBegun = true;
 #endif
             delete static_cast<T*>(this);
-        }
+        } else 
+            --m_refCount;
     }