Source/JavaScriptCore/ftl/FTLOperations.cpp

/*
 * Copyright (C) 2014 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 "FTLOperations.h"

#if ENABLE(FTL_JIT)

#include "JSCInlines.h"

namespace JSC { namespace FTL {

using namespace JSC::DFG;

extern "C" JSCell* JIT_OPERATION operationNewObjectWithButterfly(ExecState* exec, Structure* structure)
{
    VM& vm = exec->vm();
    NativeCallFrameTracer tracer(&vm, exec);
    
    Butterfly* butterfly = Butterfly::create(
        vm, nullptr, 0, structure->outOfLineCapacity(), false, IndexingHeader(), 0);
    
    return JSFinalObject::create(exec, structure, butterfly);
}

extern "C" JSCell* JIT_OPERATION operationMaterializeObjectInOSR(
    ExecState* exec, ExitTimeObjectMaterialization* materialization, EncodedJSValue* values)
{
    VM& vm = exec->vm();
    CodeBlock* codeBlock = exec->codeBlock();

    // We cannot GC. We've got pointers in evil places.
    DeferGCForAWhile deferGC(vm.heap);
    
    // In the future, we may have many different kinds of materializations. For now we just
    // materialize NewObject.
    RELEASE_ASSERT(materialization->type() == PhantomNewObject);
    
    // First figure out what the structure is.
    Structure* structure = nullptr;
    for (unsigned i = materialization->properties().size(); i--;) {
        const ExitPropertyValue& property = materialization->properties()[i];
        if (property.location() != PromotedLocationDescriptor(StructurePLoc))
            continue;
        
        structure = jsCast<Structure*>(JSValue::decode(values[i]));
    }
    RELEASE_ASSERT(structure);
    
    // Let's create that object!
    JSFinalObject* result = JSFinalObject::create(vm, structure);
    
    // Now figure out what the heck to populate the object with. Use getPropertiesConcurrently()
    // because that happens to be lower-level and more convenient. It doesn't change the
    // materialization of the property table. We want to have minimal visible effects on the
    // system. Also, don't mind that this is O(n^2). It doesn't matter. We only get here from OSR
    // exit.
    for (PropertyMapEntry entry : structure->getPropertiesConcurrently()) {
        for (unsigned i = materialization->properties().size(); i--;) {
            const ExitPropertyValue& property = materialization->properties()[i];
            if (property.location().kind() != NamedPropertyPLoc)
                continue;
            if (codeBlock->identifier(property.location().info()).impl() != entry.key)
                continue;
            
            result->putDirect(vm, entry.offset, JSValue::decode(values[i]));
        }
    }
    
    return result;
}

} } // namespace JSC::FTL

#endif // ENABLE(FTL_JIT)