Changeset 96192 in webkit

Timestamp:

Sep 27, 2011 11:32:38 PM (13 years ago)

Author:

macpherson@chromium.org

Message:

Defer call to CSSValue::isPrimitiveValue(), saves ~4% in CSSStyleSelector::applyProperty().
​https://bugs.webkit.org/show_bug.cgi?id=68964

Reviewed by Eric Seidel.

No new tests / no functionality changed.

Doing value->isPrimitiveValue() is relatviely expensive, so moving it after the early returns but
before the result is used saves a significant number of cycles. (Tested with Shark profiler in Safari).

• css/CSSStyleSelector.cpp:

(WebCore::CSSStyleSelector::applyProperty):

Location:

trunk/Source/WebCore

Files:

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

trunk/Source/WebCore/ChangeLog

@@ +1 @@
+2011-09-27  Luke Macpherson   <macpherson@chromium.org>
+
+        Defer call to CSSValue::isPrimitiveValue(), saves ~4% in CSSStyleSelector::applyProperty().
+        https://bugs.webkit.org/show_bug.cgi?id=68964
+
+        Reviewed by Eric Seidel.
+
+        No new tests / no functionality changed.
+
+        Doing value->isPrimitiveValue() is relatviely expensive, so moving it after the early returns but
+        before the result is used saves a significant number of cycles. (Tested with Shark profiler in Safari).
+
+        * css/CSSStyleSelector.cpp:
+        (WebCore::CSSStyleSelector::applyProperty):
+
 2011-09-27  Ryosuke Niwa  <rniwa@webkit.org>
 

trunk/Source/WebCore/css/CSSStyleSelector.cpp

@@ -2349 +2349 @@
 void CSSStyleSelector::applyProperty(int id, CSSValue *value)
 {
-    CSSPrimitiveValue* primitiveValue = 0;
-    if (value->isPrimitiveValue())
-        primitiveValue = static_cast<CSSPrimitiveValue*>(value);
-
-    float zoomFactor = m_style->effectiveZoom();
-
     Length l;
 
@@ -2361 +2355 @@
     bool isInherit = m_parentNode && valueType == CSSValue::CSS_INHERIT;
     bool isInitial = valueType == CSSValue::CSS_INITIAL || (!m_parentNode && valueType == CSSValue::CSS_INHERIT);
-    
+
     id = CSSProperty::resolveDirectionAwareProperty(id, m_style->direction(), m_style->writingMode());
 
@@ -2368 +2362 @@
         return;
     }
-    
+
     CSSPropertyID property = static_cast<CSSPropertyID>(id);
 
@@ -2382 +2376 @@
     }
 
+    CSSPrimitiveValue* primitiveValue = value->isPrimitiveValue() ? static_cast<CSSPrimitiveValue*>(value) : 0;
+
+    float zoomFactor = m_style->effectiveZoom();
+    
     // What follows is a list that maps the CSS properties into their corresponding front-end
     // RenderStyle values.  Shorthands (e.g. border, background) occur in this list as well and