Changeset 51624 in webkit for trunk/JavaScriptCore/runtime/JSValue.h

Timestamp:

Dec 2, 2009, 10:25:58 PM (15 years ago)

Author:

[email protected]

Message:

Add zombies to JSC
​https://bugs.webkit.org/show_bug.cgi?id=32103

Reviewed by Gavin Barraclough.

Add a compile time flag to make the JSC collector replace "unreachable"
objects with zombie objects. The zombie object is a JSCell subclass that
ASSERTs on any attempt to use the JSCell methods. In addition there are
a number of additional assertions in bottleneck code to catch zombie usage
as quickly as possible.

Grrr. Argh. Brains.

File:

• trunk/JavaScriptCore/runtime/JSValue.h (modified) (6 diffs)

trunk/JavaScriptCore/runtime/JSValue.h

@@ -169 +169 @@
         uint32_t toUInt32(ExecState*, bool& ok) const;
 
+#if ENABLE(JSC_ZOMBIES)
+        bool isZombie() const;
+#endif
+
         // Floating point conversions (this is a convenience method for webcore;
         // signle precision float is not a representation used in JS or JSC).
@@ -439 +443 @@
         JSValue v;
         v.u.asEncodedJSValue = encodedJSValue;
+#if ENABLE(JSC_ZOMBIES)
+        ASSERT(!v.isZombie());
+#endif
         return v;
     }
@@ -485 +492 @@
             u.asBits.tag = EmptyValueTag;
         u.asBits.payload = reinterpret_cast<int32_t>(ptr);
+#if ENABLE(JSC_ZOMBIES)
+        ASSERT(!isZombie());
+#endif
     }
 
@@ -494 +504 @@
             u.asBits.tag = EmptyValueTag;
         u.asBits.payload = reinterpret_cast<int32_t>(const_cast<JSCell*>(ptr));
+#if ENABLE(JSC_ZOMBIES)
+        ASSERT(!isZombie());
+#endif
     }
 
@@ -794 +807 @@
         : m_ptr(ptr)
     {
+#if ENABLE(JSC_ZOMBIES)
+        ASSERT(!isZombie());
+#endif
     }
 
@@ -799 +815 @@
         : m_ptr(const_cast<JSCell*>(ptr))
     {
+#if ENABLE(JSC_ZOMBIES)
+        ASSERT(!isZombie());
+#endif
     }