Changeset 117902 in webkit

Timestamp:

May 21, 2012 10:11:02 PM (12 years ago)

Author:

kling@webkit.org

Message:

Use stack-allocated BitArray in StylePropertySet serialization.
<​http://webkit.org/b/87071>

Reviewed by Anders Carlsson.

Use BitArray instead of BitVector to track seen properties in StylePropertySet::asText().
This removes two heap allocations from this path.

• css/StylePropertySet.cpp:

(WebCore::StylePropertySet::asText):

Location:

trunk/Source/WebCore

Files:

• ChangeLog (modified) (1 diff)
• css/StylePropertySet.cpp (modified) (4 diffs)

trunk/Source/WebCore/ChangeLog

@@ +1 @@
+2012-05-21  Andreas Kling  <kling@webkit.org>
+
+        Use stack-allocated BitArray in StylePropertySet serialization.
+        <http://webkit.org/b/87071>
+
+        Reviewed by Anders Carlsson.
+
+        Use BitArray instead of BitVector to track seen properties in StylePropertySet::asText().
+        This removes two heap allocations from this path.
+
+        * css/StylePropertySet.cpp:
+        (WebCore::StylePropertySet::asText):
+
 2012-05-21  Hajime Morrita  <morrita@chromium.org>
 

trunk/Source/WebCore/css/StylePropertySet.cpp

@@ -31 +31 @@
 #include "PropertySetCSSStyleDeclaration.h"
 #include "StylePropertyShorthand.h"
-#include <wtf/BitVector.h>
+#include <wtf/BitArray.h>
 #include <wtf/text/StringBuilder.h>
 
@@ -592 +592 @@
     const CSSProperty* repeatYProp = 0;
 
-    // FIXME: Stack-allocate the buffer for these BitVectors.
-    BitVector shorthandPropertyUsed;
-    BitVector shorthandPropertyAppeared;
+    BitArray<numCSSProperties> shorthandPropertyUsed;
+    BitArray<numCSSProperties> shorthandPropertyAppeared;
 
     unsigned size = m_properties.size();
@@ -640 +639 @@
                 value = borderPropertyValue(ReturnNullOnUncommonValues);
                 if (value.isNull())
-                    shorthandPropertyAppeared.ensureSizeAndSet(CSSPropertyBorder - firstCSSProperty, numCSSProperties);
+                    shorthandPropertyAppeared.set(CSSPropertyBorder - firstCSSProperty);
                 else
                     shorthandPropertyID = CSSPropertyBorder;
@@ -737 +736 @@
             if (!shorthandPropertyAppeared.get(shortPropertyIndex) && value.isNull())
                 value = getPropertyValue(shorthandPropertyID);
-            shorthandPropertyAppeared.ensureSizeAndSet(shortPropertyIndex, numCSSProperties);
+            shorthandPropertyAppeared.set(shortPropertyIndex);
         }
 
         if (!value.isNull()) {
             propertyID = shorthandPropertyID;
-            shorthandPropertyUsed.ensureSizeAndSet(shortPropertyIndex, numCSSProperties);
+            shorthandPropertyUsed.set(shortPropertyIndex);
         } else
             value = prop.value()->cssText();