Changeset 11213 in webkit for trunk/JavaScriptCore/kjs

Timestamp:

Nov 15, 2005, 5:45:12 PM (20 years ago)

Author:

ggaren

Message:

Reviewed by mjs.

• Fixed <rdar://problem/4342216> Installer crash in KJS::ValueImp::marked() when garbage collector runs inside call to ConstantValues::init()

I took responsibility for initializing and marking ConstantValues away
from InterpreterImp, since it's possible to reference such a value
before any interpreter has been created and after the last interpreter
has been destroyed.

InterpreterImp::lock now initializes ConstantValues. It's a good
place for the initialization because you have to call it before
creating any objects. Since ::lock can be called more than once,
I added a check in ConstantValues::init to ensure that it executes
only once.

Collector:collect is now responsible for marking ConstantValues.

We no longer clear the ConstantValues since we can't guarantee that no
one has a reference to them.

FIXME: This is hackery. The long-term plan is to make ConstantValues
use immediate values that require no initialization.

• ChangeLog:
• kjs/collector.cpp: (KJS::Collector::collect):
• kjs/internal.cpp: (KJS::InterpreterImp::InterpreterImp): (KJS::InterpreterImp::lock): (KJS::InterpreterImp::clear): (KJS::InterpreterImp::mark):
• kjs/internal.h:
• kjs/value.cpp: (KJS::ConstantValues::initIfNeeded):
• kjs/value.h:

Location:

trunk/JavaScriptCore/kjs

Files:

• collector.cpp (modified) (1 diff)
• internal.cpp (modified) (5 diffs)
• internal.h (modified) (1 diff)
• value.cpp (modified) (2 diffs)
• value.h (modified) (1 diff)

trunk/JavaScriptCore/kjs/collector.cpp

@@ -404 +404 @@
     } while (scr != InterpreterImp::s_hook);
   }
+  ConstantValues::mark();
 
   // MARK: first mark all referenced objects recursively starting out from the set of root objects

trunk/JavaScriptCore/kjs/internal.cpp

@@ -435 +435 @@
 InterpreterImp* InterpreterImp::s_hook = 0L;
 
-void InterpreterImp::globalInit()
-{
-    ConstantValues::init();
-}
-
-void InterpreterImp::globalClear()
-{
-    ConstantValues::clear();
-}
-
 typedef HashMap<ObjectImp *, InterpreterImp *, PointerHash<ObjectImp *> > InterpreterMap;
 
@@ -470 +460 @@
     // This is the first interpreter
     s_hook = next = prev = this;
-    globalInit();
   }
 
@@ -488 +477 @@
 {
   lockInterpreter();
+
+  // FIXME: Hack-o-rama. To prevent construction of a global object with a null prototype (4342216),
+  // we need to intialize our constants before the first object is constructed. InterpreterImp::lock()
+  // is a good place to do this because you have to call it before doing any allocations. Once we change our 
+  // implementation to use immediate values, we should remove this code.
+  ConstantValues::initIfNeeded();
 }
 
@@ -639 +634 @@
     // This was the last interpreter
     s_hook = 0L;
-    globalClear();
   }
   interpreterMap().remove(global);
@@ -646 +640 @@
 void InterpreterImp::mark()
 {
-  ConstantValues::mark();
   if (m_interpreter)
     m_interpreter->mark();

trunk/JavaScriptCore/kjs/internal.h

@@ -247 +247 @@
     friend class Collector;
   public:
-    static void globalInit();
-    static void globalClear();
-
     InterpreterImp(Interpreter *interp, ObjectImp *glob);
     ~InterpreterImp();

trunk/JavaScriptCore/kjs/value.cpp

@@ -188 +188 @@
 }
 
-void ConstantValues::init()
-{
+void ConstantValues::initIfNeeded()
+{
+    if (undefined)
+        return;
+    
     undefined = new UndefinedImp();
     null = new NullImp();
@@ -196 +199 @@
 }
 
-void ConstantValues::clear()
-{
-    undefined = NULL;
-    null = NULL;
-    jsTrue = NULL;
-    jsFalse = NULL;
-}
-
 void ConstantValues::mark()
 {

trunk/JavaScriptCore/kjs/value.h

@@ -197 +197 @@
     static AllocatedValueImp *jsTrue;
 
-    static void init();
-    static void clear();
+    static void initIfNeeded();
     static void mark();
 };