Changeset 145034 in webkit

Timestamp:

Mar 6, 2013 8:54:39 PM (11 years ago)

Author:

commit-queue@webkit.org

Message:

Make RuleData support up to 8191 selectors
​https://bugs.webkit.org/show_bug.cgi?id=111663

Patch by Philippe Liard <​pliard@chromium.org> on 2013-03-06
Reviewed by Andreas Kling.

r125294 made RuleData consume less memory by replacing a pointer with
an index encoded on 12 bits.
This unfortunately breaks Chrome for Android (and others) when a lot of
CSS is used or more precisely when selectorIndex cannot be stored on 12
bits.

Threfore this change decreases the number of bits used to store
m_position by 1 (from 19 to 18) and adds this extra bit to
m_selectorIndex so that values up to 8191 can be stored safely without
overflowing.

• css/RuleSet.h:

(RuleData):

Location:

trunk/Source/WebCore

Files:

• ChangeLog (modified) (1 diff)
• css/RuleSet.h (modified) (1 diff)

trunk/Source/WebCore/ChangeLog

@@ +1 @@
+2013-03-06  Philippe Liard  <pliard@chromium.org>
+
+        Make RuleData support up to 8191 selectors
+        https://bugs.webkit.org/show_bug.cgi?id=111663
+
+        Reviewed by Andreas Kling.
+
+        r125294 made RuleData consume less memory by replacing a pointer with
+        an index encoded on 12 bits.
+        This unfortunately breaks Chrome for Android (and others) when a lot of
+        CSS is used or more precisely when selectorIndex cannot be stored on 12
+        bits.
+
+        Threfore this change decreases the number of bits used to store
+        m_position by 1 (from 19 to 18) and adds this extra bit to
+        m_selectorIndex so that values up to 8191 can be stored safely without
+        overflowing.
+
+        * css/RuleSet.h:
+        (RuleData):
+
 2013-03-06  Seokju Kwon  <seokju.kwon@gmail.com>
 

trunk/Source/WebCore/css/RuleSet.h

@@ -79 +79 @@
 private:
     StyleRule* m_rule;
-    unsigned m_selectorIndex : 12;
+    unsigned m_selectorIndex : 13;
     // This number was picked fairly arbitrarily. We can probably lower it if we need to.
     // Some simple testing showed <100,000 RuleData's on large sites.
-    unsigned m_position : 19;
+    unsigned m_position : 18;
     unsigned m_hasFastCheckableSelector : 1;
     unsigned m_specificity : 24;