Changeset 161369 in webkit

Timestamp:

Jan 6, 2014, 1:48:15 PM (12 years ago)

Author:

mark.lam@apple.com

Message:

Follow up patch to remove the need for VMEntryScope::m_prevFirstEntryScope.
​https://bugs.webkit.org/show_bug.cgi?id=126266.

Reviewed by Geoffrey Garen.

There can only be one firstEntryScope. Instead of saving the previous value of
VM::firstEntryScope, we now check if the firstEntryScope is the same as this
VMEntryScope in its destructor. If so, we will set VM::firstEntryScope to 0.

• runtime/VMEntryScope.cpp:

(JSC::VMEntryScope::VMEntryScope):
(JSC::VMEntryScope::~VMEntryScope):

• runtime/VMEntryScope.h:

Location:

branches/jsCStack/Source/JavaScriptCore

Files:

• ChangeLog (modified) (2 diffs)
• runtime/VMEntryScope.cpp (modified) (2 diffs)
• runtime/VMEntryScope.h (modified) (1 diff)

branches/jsCStack/Source/JavaScriptCore/ChangeLog

@@ +1 @@
+2014-01-06  Mark Lam  <mark.lam@apple.com>
+
+        Follow up patch to remove the need for VMEntryScope::m_prevFirstEntryScope.
+        https://bugs.webkit.org/show_bug.cgi?id=126266.
+
+        Reviewed by Geoffrey Garen.
+
+        There can only be one firstEntryScope. Instead of saving the previous value of
+        VM::firstEntryScope, we now check if the firstEntryScope is the same as this
+        VMEntryScope in its destructor. If so, we will set VM::firstEntryScope to 0.
+
+        * runtime/VMEntryScope.cpp:
+        (JSC::VMEntryScope::VMEntryScope):
+        (JSC::VMEntryScope::~VMEntryScope):
+        * runtime/VMEntryScope.h:
+
 2014-01-06  Mark Lam  <mark.lam@apple.com>
 
@@ -513 +529 @@
 
         Not yet reviewed.
+
+        This patch is so that we can distinguish firstEntryScope from topEntryScope
+        which will be introduced later in https://bugs.webkit.org/show_bug.cgi?id=126334.
 
         Also renamed VMEntryScope::m_prev to m_prevFirstEntryScope.

branches/jsCStack/Source/JavaScriptCore/runtime/VMEntryScope.cpp

@@ -38 +38 @@
     , m_globalObject(globalObject)
     , m_prevStackUsage(0)
-    , m_prevFirstEntryScope(vm.firstEntryScope)
     , m_prevTopEntryScope(vm.topEntryScope)
     , m_prevStackLimit(vm.stackLimit())
@@ -84 +83 @@
 VMEntryScope::~VMEntryScope()
 {
-    m_vm.firstEntryScope = m_prevFirstEntryScope;
+    if (m_vm.firstEntryScope == this)
+        m_vm.firstEntryScope = nullptr;
     m_vm.topEntryScope = m_prevTopEntryScope;
     m_vm.setStackLimit(m_prevStackLimit);

branches/jsCStack/Source/JavaScriptCore/runtime/VMEntryScope.h

@@ -60 +60 @@
 
     // The following pointers may point to a different thread's stack.
-    VMEntryScope* m_prevFirstEntryScope;
     VMEntryScope* m_prevTopEntryScope;
     void* m_prevStackLimit;