Imported QtWebKit TP3 (git b57bc6801f1876c3220d5a4bfea33d620d477443)

Change-Id: I3b1d8a2808782c9f34d50240000e20cb38d3680f
Reviewed-by: Konstantin Tokarev <annulen@yandex.ru>

1 files changed, 185 insertions, 0 deletions

diff --git a/Source/JavaScriptCore/runtime/DirectArguments.cpp b/Source/JavaScriptCore/runtime/DirectArguments.cpp
new file mode 100644
index 000000000..b840df9ed
--- /dev/null
+++ b/Source/JavaScriptCore/runtime/DirectArguments.cpp
@@ -0,0 +1,185 @@
+/*
+ * Copyright (C) 2015 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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``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 INC. OR
+ * 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 "DirectArguments.h"
+
+#include "CodeBlock.h"
+#include "CopiedBlockInlines.h"
+#include "CopyVisitorInlines.h"
+#include "GenericArgumentsInlines.h"
+#include "JSCInlines.h"
+
+namespace JSC {
+
+STATIC_ASSERT_IS_TRIVIALLY_DESTRUCTIBLE(DirectArguments);
+
+const ClassInfo DirectArguments::s_info = { "Arguments", &Base::s_info, 0, CREATE_METHOD_TABLE(DirectArguments) };
+
+DirectArguments::DirectArguments(VM& vm, Structure* structure, unsigned length, unsigned capacity)
+    : GenericArguments(vm, structure)
+    , m_length(length)
+    , m_minCapacity(capacity)
+{
+    // When we construct the object from C++ code, we expect the capacity to be at least as large as
+    // length. JIT-allocated DirectArguments objects play evil tricks, though.
+    ASSERT(capacity >= length);
+}
+
+DirectArguments* DirectArguments::createUninitialized(
+    VM& vm, Structure* structure, unsigned length, unsigned capacity)
+{
+    DirectArguments* result =
+        new (NotNull, allocateCell<DirectArguments>(vm.heap, allocationSize(capacity)))
+        DirectArguments(vm, structure, length, capacity);
+    result->finishCreation(vm);
+    return result;
+}
+
+DirectArguments* DirectArguments::create(VM& vm, Structure* structure, unsigned length, unsigned capacity)
+{
+    DirectArguments* result = createUninitialized(vm, structure, length, capacity);
+    
+    for (unsigned i = capacity; i--;)
+        result->storage()[i].clear();
+    
+    return result;
+}
+
+DirectArguments* DirectArguments::createByCopying(ExecState* exec)
+{
+    VM& vm = exec->vm();
+    
+    unsigned length = exec->argumentCount();
+    unsigned capacity = std::max(length, static_cast<unsigned>(exec->codeBlock()->numParameters() - 1));
+    DirectArguments* result = createUninitialized(
+        vm, exec->lexicalGlobalObject()->directArgumentsStructure(), length, capacity);
+    
+    for (unsigned i = capacity; i--;)
+        result->storage()[i].set(vm, result, exec->getArgumentUnsafe(i));
+    
+    result->callee().set(vm, result, jsCast<JSFunction*>(exec->callee()));
+    
+    return result;
+}
+
+size_t DirectArguments::estimatedSize(JSCell* cell)
+{
+    DirectArguments* thisObject = jsCast<DirectArguments*>(cell);
+    size_t overridesSize = thisObject->m_overrides ? thisObject->overridesSize() : 0;
+    return Base::estimatedSize(cell) + overridesSize;
+}
+
+void DirectArguments::visitChildren(JSCell* thisCell, SlotVisitor& visitor)
+{
+    DirectArguments* thisObject = static_cast<DirectArguments*>(thisCell);
+    ASSERT_GC_OBJECT_INHERITS(thisObject, info());
+    Base::visitChildren(thisObject, visitor);
+    
+    visitor.appendValues(thisObject->storage(), std::max(thisObject->m_length, thisObject->m_minCapacity));
+    visitor.append(&thisObject->m_callee);
+    
+    if (thisObject->m_overrides) {
+        visitor.copyLater(
+            thisObject, DirectArgumentsOverridesCopyToken,
+            thisObject->m_overrides.getWithoutBarrier(), thisObject->overridesSize());
+    }
+}
+
+void DirectArguments::copyBackingStore(JSCell* thisCell, CopyVisitor& visitor, CopyToken token)
+{
+    DirectArguments* thisObject = static_cast<DirectArguments*>(thisCell);
+    ASSERT_GC_OBJECT_INHERITS(thisObject, info());
+    
+    RELEASE_ASSERT(token == DirectArgumentsOverridesCopyToken);
+    
+    void* oldOverrides = thisObject->m_overrides.getWithoutBarrier();
+    if (visitor.checkIfShouldCopy(oldOverrides)) {
+        bool* newOverrides = static_cast<bool*>(visitor.allocateNewSpace(thisObject->overridesSize()));
+        memcpy(newOverrides, oldOverrides, thisObject->m_length);
+        thisObject->m_overrides.setWithoutBarrier(newOverrides);
+        visitor.didCopy(oldOverrides, thisObject->overridesSize());
+    }
+}
+
+Structure* DirectArguments::createStructure(VM& vm, JSGlobalObject* globalObject, JSValue prototype)
+{
+    return Structure::create(vm, globalObject, prototype, TypeInfo(DirectArgumentsType, StructureFlags), info());
+}
+
+void DirectArguments::overrideThings(VM& vm)
+{
+    RELEASE_ASSERT(!m_overrides);
+    
+    putDirect(vm, vm.propertyNames->length, jsNumber(m_length), DontEnum);
+    putDirect(vm, vm.propertyNames->callee, m_callee.get(), DontEnum);
+    putDirect(vm, vm.propertyNames->iteratorSymbol, globalObject()->arrayProtoValuesFunction(), DontEnum);
+    
+    void* backingStore;
+    RELEASE_ASSERT(vm.heap.tryAllocateStorage(this, overridesSize(), &backingStore));
+    bool* overrides = static_cast<bool*>(backingStore);
+    m_overrides.set(vm, this, overrides);
+    for (unsigned i = m_length; i--;)
+        overrides[i] = false;
+}
+
+void DirectArguments::overrideThingsIfNecessary(VM& vm)
+{
+    if (!m_overrides)
+        overrideThings(vm);
+}
+
+void DirectArguments::overrideArgument(VM& vm, unsigned index)
+{
+    overrideThingsIfNecessary(vm);
+    m_overrides.get(this)[index] = true;
+}
+
+void DirectArguments::copyToArguments(ExecState* exec, VirtualRegister firstElementDest, unsigned offset, unsigned length)
+{
+    if (!m_overrides) {
+        unsigned limit = std::min(length + offset, m_length);
+        unsigned i;
+        VirtualRegister start = firstElementDest - offset;
+        for (i = offset; i < limit; ++i)
+            exec->r(start + i) = storage()[i].get();
+        for (; i < length; ++i)
+            exec->r(start + i) = get(exec, i);
+        return;
+    }
+
+    GenericArguments::copyToArguments(exec, firstElementDest, offset, length);
+}
+
+unsigned DirectArguments::overridesSize()
+{
+    // We always allocate something; in the relatively uncommon case of overriding an empty argument we
+    // still allocate so that m_overrides is non-null. We use that to indicate that the other properties
+    // (length, etc) are overridden.
+    return WTF::roundUpToMultipleOf<8>(m_length ? m_length : 1);
+}
+
+} // namespace JSC
+