Changeset 103672 in webkit for trunk/Source/JavaScriptCore/yarr/YarrPattern.cpp

Timestamp:

Dec 25, 2011, 1:21:06 PM (13 years ago)

Author:

[email protected]

Message:

Yarr: Avoid copying vectors in CharacterClassConstructor.
<​http://webkit.org/b/75206>

Reviewed by Darin Adler.

Yarr::CharacterClassConstructor::charClass() was hot when loading twitter
feeds (1.2%), replace the usage of Vector::append() by swap() since we're
always clearing the source vector afterwards anyway.

• yarr/YarrPattern.cpp:

(JSC::Yarr::CharacterClassConstructor::charClass):

File:

• trunk/Source/JavaScriptCore/yarr/YarrPattern.cpp (modified) (1 diff)

trunk/Source/JavaScriptCore/yarr/YarrPattern.cpp

@@ -145 +145 @@
         CharacterClass* characterClass = new CharacterClass(0);
 
-        characterClass->m_matches.append(m_matches);
-        characterClass->m_ranges.append(m_ranges);
-        characterClass->m_matchesUnicode.append(m_matchesUnicode);
-        characterClass->m_rangesUnicode.append(m_rangesUnicode);
-
-        reset();
+        characterClass->m_matches.swap(m_matches);
+        characterClass->m_ranges.swap(m_ranges);
+        characterClass->m_matchesUnicode.swap(m_matchesUnicode);
+        characterClass->m_rangesUnicode.swap(m_rangesUnicode);
 
         return characterClass;