1 files changed, 244 insertions, 0 deletions
diff --git a/Source/JavaScriptCore/runtime/JSActivation.cpp b/Source/JavaScriptCore/runtime/JSActivation.cpp
new file mode 100644
index 000000000..83d1ee493
--- /dev/null
+++ b/Source/JavaScriptCore/runtime/JSActivation.cpp
@@ -0,0 +1,244 @@
+/*
+ * Copyright (C) 2008, 2009 Apple Inc. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1.  Redistributions of source code must retain the above copyright
+ *     notice, this list of conditions and the following disclaimer.
+ * 2.  Redistributions in binary form must reproduce the above copyright
+ *     notice, this list of conditions and the following disclaimer in the
+ *     documentation and/or other materials provided with the distribution.
+ * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of
+ *     its contributors may be used to endorse or promote products derived
+ *     from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
+ * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+ 
+#include "config.h"
+#include "JSActivation.h"
+
+#include "Arguments.h"
+#include "Interpreter.h"
+#include "JSFunction.h"
+
+using namespace std;
+
+namespace JSC {
+
+ASSERT_CLASS_FITS_IN_CELL(JSActivation);
+
+const ClassInfo JSActivation::s_info = { "JSActivation", &Base::s_info, 0, 0, CREATE_METHOD_TABLE(JSActivation) };
+
+JSActivation::JSActivation(CallFrame* callFrame, FunctionExecutable* functionExecutable)
+    : Base(callFrame->globalData(), callFrame->globalData().activationStructure.get(), functionExecutable->symbolTable(), callFrame->registers())
+    , m_numCapturedArgs(max(callFrame->argumentCount(), functionExecutable->parameterCount()))
+    , m_numCapturedVars(functionExecutable->capturedVariableCount())
+    , m_requiresDynamicChecks(functionExecutable->usesEval())
+    , m_argumentsRegister(functionExecutable->generatedBytecode().argumentsRegister())
+{
+}
+
+void JSActivation::finishCreation(CallFrame* callFrame)
+{
+    Base::finishCreation(callFrame->globalData());
+    ASSERT(inherits(&s_info));
+
+    // We have to manually ref and deref the symbol table as JSVariableObject
+    // doesn't know about SharedSymbolTable
+    static_cast<SharedSymbolTable*>(m_symbolTable)->ref();
+    callFrame->globalData().heap.addFinalizer(this, &finalize);
+}
+
+void JSActivation::finalize(JSCell* cell)
+{
+    static_cast<SharedSymbolTable*>(jsCast<JSActivation*>(cell)->m_symbolTable)->deref();
+}
+
+void JSActivation::visitChildren(JSCell* cell, SlotVisitor& visitor)
+{
+    JSActivation* thisObject = jsCast<JSActivation*>(cell);
+    ASSERT_GC_OBJECT_INHERITS(thisObject, &s_info);
+    COMPILE_ASSERT(StructureFlags & OverridesVisitChildren, OverridesVisitChildrenWithoutSettingFlag);
+    ASSERT(thisObject->structure()->typeInfo().overridesVisitChildren());
+    Base::visitChildren(thisObject, visitor);
+
+    // No need to mark our registers if they're still in the RegisterFile.
+    WriteBarrier<Unknown>* registerArray = thisObject->m_registerArray.get();
+    if (!registerArray)
+        return;
+
+    visitor.appendValues(registerArray, thisObject->m_numCapturedArgs);
+
+    // Skip 'this' and call frame.
+    visitor.appendValues(registerArray + CallFrame::offsetFor(thisObject->m_numCapturedArgs + 1), thisObject->m_numCapturedVars);
+}
+
+inline bool JSActivation::symbolTableGet(const Identifier& propertyName, PropertySlot& slot)
+{
+    SymbolTableEntry entry = symbolTable().inlineGet(propertyName.impl());
+    if (entry.isNull())
+        return false;
+    if (entry.getIndex() >= m_numCapturedVars)
+        return false;
+
+    slot.setValue(registerAt(entry.getIndex()).get());
+    return true;
+}
+
+inline bool JSActivation::symbolTablePut(ExecState* exec, const Identifier& propertyName, JSValue value, bool shouldThrow)
+{
+    JSGlobalData& globalData = exec->globalData();
+    ASSERT(!Heap::heap(value) || Heap::heap(value) == Heap::heap(this));
+    
+    SymbolTableEntry entry = symbolTable().inlineGet(propertyName.impl());
+    if (entry.isNull())
+        return false;
+    if (entry.isReadOnly()) {
+        if (shouldThrow)
+            throwTypeError(exec, StrictModeReadonlyPropertyWriteError);
+        return true;
+    }
+    if (entry.getIndex() >= m_numCapturedVars)
+        return false;
+
+    registerAt(entry.getIndex()).set(globalData, this, value);
+    return true;
+}
+
+void JSActivation::getOwnPropertyNames(JSObject* object, ExecState* exec, PropertyNameArray& propertyNames, EnumerationMode mode)
+{
+    JSActivation* thisObject = jsCast<JSActivation*>(object);
+    SymbolTable::const_iterator end = thisObject->symbolTable().end();
+    for (SymbolTable::const_iterator it = thisObject->symbolTable().begin(); it != end; ++it) {
+        if (it->second.getAttributes() & DontEnum && mode != IncludeDontEnumProperties)
+            continue;
+        if (it->second.getIndex() >= thisObject->m_numCapturedVars)
+            continue;
+        propertyNames.add(Identifier(exec, it->first.get()));
+    }
+    // Skip the JSVariableObject implementation of getOwnPropertyNames
+    JSObject::getOwnPropertyNames(thisObject, exec, propertyNames, mode);
+}
+
+inline bool JSActivation::symbolTablePutWithAttributes(JSGlobalData& globalData, const Identifier& propertyName, JSValue value, unsigned attributes)
+{
+    ASSERT(!Heap::heap(value) || Heap::heap(value) == Heap::heap(this));
+    
+    SymbolTable::iterator iter = symbolTable().find(propertyName.impl());
+    if (iter == symbolTable().end())
+        return false;
+    SymbolTableEntry& entry = iter->second;
+    ASSERT(!entry.isNull());
+    if (entry.getIndex() >= m_numCapturedVars)
+        return false;
+
+    entry.setAttributes(attributes);
+    registerAt(entry.getIndex()).set(globalData, this, value);
+    return true;
+}
+
+bool JSActivation::getOwnPropertySlot(JSCell* cell, ExecState* exec, const Identifier& propertyName, PropertySlot& slot)
+{
+    JSActivation* thisObject = jsCast<JSActivation*>(cell);
+    if (propertyName == exec->propertyNames().arguments) {
+        slot.setCustom(thisObject, thisObject->getArgumentsGetter());
+        return true;
+    }
+
+    if (thisObject->symbolTableGet(propertyName, slot))
+        return true;
+
+    if (WriteBarrierBase<Unknown>* location = thisObject->getDirectLocation(exec->globalData(), propertyName)) {
+        slot.setValue(location->get());
+        return true;
+    }
+
+    // We don't call through to JSObject because there's no way to give an 
+    // activation object getter properties or a prototype.
+    ASSERT(!thisObject->hasGetterSetterProperties());
+    ASSERT(thisObject->prototype().isNull());
+    return false;
+}
+
+void JSActivation::put(JSCell* cell, ExecState* exec, const Identifier& propertyName, JSValue value, PutPropertySlot& slot)
+{
+    JSActivation* thisObject = jsCast<JSActivation*>(cell);
+    ASSERT(!Heap::heap(value) || Heap::heap(value) == Heap::heap(thisObject));
+
+    if (thisObject->symbolTablePut(exec, propertyName, value, slot.isStrictMode()))
+        return;
+
+    // We don't call through to JSObject because __proto__ and getter/setter 
+    // properties are non-standard extensions that other implementations do not
+    // expose in the activation object.
+    ASSERT(!thisObject->hasGetterSetterProperties());
+    thisObject->putDirect(exec->globalData(), propertyName, value, 0, true, slot);
+}
+
+// FIXME: Make this function honor ReadOnly (const) and DontEnum
+void JSActivation::putWithAttributes(JSObject* object, ExecState* exec, const Identifier& propertyName, JSValue value, unsigned attributes)
+{
+    JSActivation* thisObject = jsCast<JSActivation*>(object);
+    ASSERT(!Heap::heap(value) || Heap::heap(value) == Heap::heap(thisObject));
+
+    if (thisObject->symbolTablePutWithAttributes(exec->globalData(), propertyName, value, attributes))
+        return;
+
+    // We don't call through to JSObject because __proto__ and getter/setter 
+    // properties are non-standard extensions that other implementations do not
+    // expose in the activation object.
+    ASSERT(!thisObject->hasGetterSetterProperties());
+    JSObject::putWithAttributes(thisObject, exec, propertyName, value, attributes);
+}
+
+bool JSActivation::deleteProperty(JSCell* cell, ExecState* exec, const Identifier& propertyName)
+{
+    if (propertyName == exec->propertyNames().arguments)
+        return false;
+
+    return Base::deleteProperty(cell, exec, propertyName);
+}
+
+JSObject* JSActivation::toThisObject(JSCell*, ExecState* exec)
+{
+    return exec->globalThisValue();
+}
+
+JSValue JSActivation::argumentsGetter(ExecState*, JSValue slotBase, const Identifier&)
+{
+    JSActivation* activation = asActivation(slotBase);
+    CallFrame* callFrame = CallFrame::create(reinterpret_cast<Register*>(activation->m_registers));
+    int argumentsRegister = activation->m_argumentsRegister;
+    if (JSValue arguments = callFrame->uncheckedR(argumentsRegister).jsValue())
+        return arguments;
+    int realArgumentsRegister = unmodifiedArgumentsRegister(argumentsRegister);
+
+    JSValue arguments = JSValue(Arguments::create(callFrame->globalData(), callFrame));
+    callFrame->uncheckedR(argumentsRegister) = arguments;
+    callFrame->uncheckedR(realArgumentsRegister) = arguments;
+    
+    ASSERT(callFrame->uncheckedR(realArgumentsRegister).jsValue().inherits(&Arguments::s_info));
+    return callFrame->uncheckedR(realArgumentsRegister).jsValue();
+}
+
+// These two functions serve the purpose of isolating the common case from a
+// PIC branch.
+
+PropertySlot::GetValueFunc JSActivation::getArgumentsGetter()
+{
+    return argumentsGetter;
+}
+
+} // namespace JSC