X-Git-Url: https://git.saurik.com/apple/javascriptcore.git/blobdiff_plain/2d39b0e377c0896910ee49ae70082ba665faf986..ed1e77d3adeb83d26fd1dfb16dd84cabdcefd250:/runtime/JSEnvironmentRecord.h diff --git a/runtime/JSEnvironmentRecord.h b/runtime/JSEnvironmentRecord.h new file mode 100644 index 0000000..35807ba --- /dev/null +++ b/runtime/JSEnvironmentRecord.h @@ -0,0 +1,117 @@ +/* + * Copyright (C) 2007, 2008, 2012, 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. + * 3. Neither the name of Apple 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. + */ + +#ifndef JSEnvironmentRecord_h +#define JSEnvironmentRecord_h + +#include "JSObject.h" +#include "JSSymbolTableObject.h" +#include "Register.h" +#include "SymbolTable.h" + +namespace JSC { + +class LLIntOffsetsExtractor; +class Register; + +class JSEnvironmentRecord : public JSSymbolTableObject { + friend class JIT; + friend class LLIntOffsetsExtractor; + +public: + typedef JSSymbolTableObject Base; + static const unsigned StructureFlags = Base::StructureFlags; + + WriteBarrierBase* variables() + { + return bitwise_cast*>(bitwise_cast(this) + offsetOfVariables()); + } + + bool isValid(ScopeOffset offset) + { + return !!offset && offset.offset() < symbolTable()->scopeSize(); + } + + WriteBarrierBase& variableAt(ScopeOffset offset) + { + ASSERT(isValid(offset)); + return variables()[offset.offset()]; + } + + static size_t offsetOfVariables() + { + return WTF::roundUpToMultipleOf)>(sizeof(JSEnvironmentRecord)); + } + + static ptrdiff_t offsetOfVariable(ScopeOffset offset) + { + return offsetOfVariables() + offset.offset() * sizeof(WriteBarrier); + } + + DECLARE_INFO; + + static size_t allocationSizeForScopeSize(unsigned scopeSize) + { + return offsetOfVariables() + scopeSize * sizeof(WriteBarrier); + } + + static size_t allocationSize(SymbolTable* symbolTable) + { + return allocationSizeForScopeSize(symbolTable->scopeSize()); + } + +protected: + JSEnvironmentRecord( + VM& vm, + Structure* structure, + JSScope* scope, + SymbolTable* symbolTable) + : Base(vm, structure, scope, symbolTable) + { + } + + void finishCreationUninitialized(VM& vm) + { + Base::finishCreation(vm); + } + + void finishCreation(VM& vm) + { + finishCreationUninitialized(vm); + for (unsigned i = symbolTable()->scopeSize(); i--;) { + // Filling this with undefined is useful because that's what variables start out as. + variableAt(ScopeOffset(i)).setUndefined(); + } + } + + static void visitChildren(JSCell*, SlotVisitor&); +}; + +} // namespace JSC + +#endif // JSEnvironmentRecord_h