DOM string cache should hash pointers, not characters
https://bugs.webkit.org/show_bug.cgi?id=88175
Reviewed by Phil Pizlo and Sam Weinig.
../JavaScriptCore:
* heap/Weak.h:
(JSC::weakAdd):
(JSC::weakRemove): Made these function templates slightly more generic
to accommodate new client types.
../WebCore:
Dromaeo DOM Core reports no change.
http://trac.webkit.org/changeset/84934 accidentally changed from hashing
pointers to hashing characters, due to template defaults. Let's change back.
Hashing characters is not so good because:
(1) It's not memory-safe with HashMap::set(). HashMap::set() replaces
the value but not the key. Since our values own our keys, we need to
ensure object identity between key and value, or the key can be freed
prematurely. (This is impossible to demonstrate with our current
eager sweep behavior, but it shows up as crashes in layout tests if you
change to lazy sweep.)
(2) It's slower.
* bindings/js/DOMWrapperWorld.h:
(WebCore): Override the default hash, which hashes based on characters.
git-svn-id: http://svn.webkit.org/repository/webkit/trunk@119341 268f45cc-cd09-0410-ab3c-d52691b4dbfc
diff --git a/Source/JavaScriptCore/ChangeLog b/Source/JavaScriptCore/ChangeLog
index 9b7e407..b8e0750 100644
--- a/Source/JavaScriptCore/ChangeLog
+++ b/Source/JavaScriptCore/ChangeLog
@@ -1,3 +1,15 @@
+2012-06-02 Geoffrey Garen <ggaren@apple.com>
+
+ DOM string cache should hash pointers, not characters
+ https://bugs.webkit.org/show_bug.cgi?id=88175
+
+ Reviewed by Phil Pizlo and Sam Weinig.
+
+ * heap/Weak.h:
+ (JSC::weakAdd):
+ (JSC::weakRemove): Made these function templates slightly more generic
+ to accommodate new client types.
+
2012-06-01 Filip Pizlo <fpizlo@apple.com>
DFG CFA should know that PutByVal can clobber the world
