Changeset 171558 in webkit

Timestamp:

Jul 24, 2014 4:56:34 PM (10 years ago)

Author:

Joseph Pecoraro

Message:

JSLock release should only modify the AtomicStringTable if it modified in acquire
​https://bugs.webkit.org/show_bug.cgi?id=135143

Reviewed by Darin Adler.

• runtime/JSLock.cpp:

(JSC::JSLock::JSLock):
Initialize the member variable to nullptr.

(JSC::JSLock::willDestroyVM):
Update style to use nullptr instead of 0.

(JSC::JSLock::willReleaseLock):
We should only reset the thread data's atomic string table if
didAcquireLock changed it. m_entryAtomicStringTable will have
been set by didAcquireLock if it changed, or nullptr if it didn't.
This way we are sure we are balanced, regardless of m_vm changes.

Location:

trunk/Source/JavaScriptCore

Files:

• ChangeLog (modified) (1 diff)
• runtime/JSLock.cpp (modified) (4 diffs)

trunk/Source/JavaScriptCore/ChangeLog

@@ +1 @@
+2014-07-24  Joseph Pecoraro  <pecoraro@apple.com>
+
+        JSLock release should only modify the AtomicStringTable if it modified in acquire
+        https://bugs.webkit.org/show_bug.cgi?id=135143
+
+        Reviewed by Darin Adler.
+
+        * runtime/JSLock.cpp:
+        (JSC::JSLock::JSLock):
+        Initialize the member variable to nullptr.
+
+        (JSC::JSLock::willDestroyVM):
+        Update style to use nullptr instead of 0.
+
+        (JSC::JSLock::willReleaseLock):
+        We should only reset the thread data's atomic string table if
+        didAcquireLock changed it. m_entryAtomicStringTable will have
+        been set by didAcquireLock if it changed, or nullptr if it didn't.
+        This way we are sure we are balanced, regardless of m_vm changes.
+
 2014-07-24  Peyton Randolph  <prandolph@apple.com>
 

trunk/Source/JavaScriptCore/runtime/JSLock.cpp

@@ -84 +84 @@
     , m_hasExclusiveThread(false)
     , m_vm(vm)
+    , m_entryAtomicStringTable(nullptr)
 {
 }
@@ -94 +95 @@
 {
     ASSERT_UNUSED(vm, m_vm == vm);
-    m_vm = 0;
+    m_vm = nullptr;
 }
 
@@ -140 +141 @@
     m_vm->setLastStackTop(threadData.savedLastStackTop());
 
+    ASSERT(!m_entryAtomicStringTable);
     m_entryAtomicStringTable = threadData.setCurrentAtomicStringTable(m_vm->atomicStringTable());
+    ASSERT(m_entryAtomicStringTable);
+
     m_vm->heap.machineThreads().addCurrentThread();
 }
@@ -171 +175 @@
         m_vm->setStackPointerAtVMEntry(nullptr);
 
-    wtfThreadData().setCurrentAtomicStringTable(m_entryAtomicStringTable);
+    if (m_entryAtomicStringTable) {
+        wtfThreadData().setCurrentAtomicStringTable(m_entryAtomicStringTable);
+        m_entryAtomicStringTable = nullptr;
+    }
 }