[ES6] implement block scoping to enable 'let'
authorsaambarati1@gmail.com <saambarati1@gmail.com@268f45cc-cd09-0410-ab3c-d52691b4dbfc>
Wed, 15 Jul 2015 21:41:08 +0000 (21:41 +0000)
committersaambarati1@gmail.com <saambarati1@gmail.com@268f45cc-cd09-0410-ab3c-d52691b4dbfc>
Wed, 15 Jul 2015 21:41:08 +0000 (21:41 +0000)
commitc22a42d070a8556e76daf9b3fc475d57280f6c03
treeb21fd3830804feb63b06a8b811a0e0fa75cea0f4
parent7b0e5b369b5ddfbbb43b8784bc2b4a8978b11c7f
[ES6] implement block scoping to enable 'let'
https://bugs.webkit.org/show_bug.cgi?id=142944

Reviewed by Filip Pizlo.

Source/JavaScriptCore:

* CMakeLists.txt:
* JavaScriptCore.vcxproj/JavaScriptCore.vcxproj:
* JavaScriptCore.vcxproj/JavaScriptCore.vcxproj.filters:
* JavaScriptCore.xcodeproj/project.pbxproj:
* builtins/BuiltinExecutables.cpp:
(JSC::BuiltinExecutables::createExecutableInternal):
* bytecode/BytecodeList.json:
This patch adds a new opcode and removes op_pop_scope:
1) op_get_parent_scope returns the parent scope but doesn't
implicitly write that scope into the scope register. op_pop_scope
is now reduced to op_get_parent_scope followed by op_mov.

* bytecode/BytecodeUseDef.h:
(JSC::computeUsesForBytecodeOffset):
(JSC::computeDefsForBytecodeOffset):
* bytecode/CodeBlock.cpp:
(JSC::CodeBlock::dumpBytecode):
(JSC::CodeBlock::CodeBlock):
(JSC::CodeBlock::stronglyVisitStrongReferences):
* bytecode/CodeBlock.h:
(JSC::CodeBlock::addStringSwitchJumpTable):
(JSC::CodeBlock::stringSwitchJumpTable):
(JSC::CodeBlock::symbolTable):
(JSC::CodeBlock::evalCodeCache):
(JSC::CodeBlock::setConstantRegisters):
(JSC::CodeBlock::replaceConstant):
op_put_to_scope for LocalClosureVar now takes as an argument
the constant index for the Symbol Table it will be putting into.
This argument is only used to communicate from the BytecodeGenerator
to CodeBlock linking time and it is not present in the linked bytecode.

op_put_to_scope for non LocalClosureVar takes, at the same index, an
argument that represents the local scope depth which it uses for
JSScope::abstractResolve to know how many scopes it needs to skip.
Again, this is not in the linked code.
op_get_from_scope and op_resolve_scope also take as an argument
the local scope depth to use in JSScope::abstractResolve. Again,
this is not used in the linked code.

* bytecode/EvalCodeCache.h:
(JSC::EvalCodeCache::tryGet):
(JSC::EvalCodeCache::getSlow):
(JSC::EvalCodeCache::clear):
(JSC::EvalCodeCache::isCacheable):
When direct eval is called and passed a scope that
corresponds to a lexical scope, we can't safely cache
that code because we won't be able to guarantee
that the cached code is always executed in the same scope.
Consider this example:
function foo() {
    let x = 20;
    eval("x;");
    if (b) {
        let x = 30;
        if (b) {
            let y = 40;
            eval("x;")
        }
    }
}

We can't reuse resolution depth when linking get_from_scope in evals.

* bytecode/UnlinkedCodeBlock.cpp:
(JSC::generateFunctionCodeBlock):
(JSC::UnlinkedFunctionExecutable::UnlinkedFunctionExecutable):
(JSC::UnlinkedFunctionExecutable::parameterCount):
* bytecode/UnlinkedCodeBlock.h:
Unlinked functions now know the variables that were under TDZ in their parent
scope.

(JSC::UnlinkedCodeBlock::symbolTable):
(JSC::UnlinkedCodeBlock::setSymbolTable):
(JSC::UnlinkedCodeBlock::setSymbolTableConstantIndex):
(JSC::UnlinkedCodeBlock::symbolTableConstantIndex):
(JSC::UnlinkedCodeBlock::vm):
* bytecompiler/BytecodeGenerator.cpp:
(JSC::BytecodeGenerator::generate):
(JSC::BytecodeGenerator::BytecodeGenerator):
(JSC::BytecodeGenerator::~BytecodeGenerator):
(JSC::BytecodeGenerator::newRegister):
(JSC::BytecodeGenerator::reclaimFreeRegisters):
(JSC::BytecodeGenerator::newBlockScopeVariable):
(JSC::BytecodeGenerator::newTemporary):
(JSC::BytecodeGenerator::emitProfileType):
(JSC::BytecodeGenerator::emitLoadGlobalObject):
(JSC::BytecodeGenerator::pushLexicalScope):
(JSC::BytecodeGenerator::popLexicalScope):
(JSC::BytecodeGenerator::prepareLexicalScopeForNextForLoopIteration):
(JSC::BytecodeGenerator::variable):
(JSC::BytecodeGenerator::variablePerSymbolTable):
(JSC::BytecodeGenerator::variableForLocalEntry):
(JSC::BytecodeGenerator::createVariable):
(JSC::BytecodeGenerator::emitResolveScope):
(JSC::BytecodeGenerator::emitGetFromScope):
(JSC::BytecodeGenerator::emitPutToScope):
(JSC::BytecodeGenerator::initializeVariable):
(JSC::BytecodeGenerator::emitTDZCheck):
(JSC::BytecodeGenerator::needsTDZCheck):
(JSC::BytecodeGenerator::emitTDZCheckIfNecessary):
(JSC::BytecodeGenerator::liftTDZCheckIfPossible):
(JSC::BytecodeGenerator::getVariablesUnderTDZ):
(JSC::BytecodeGenerator::emitNewObject):
(JSC::BytecodeGenerator::emitPushWithScope):
(JSC::BytecodeGenerator::emitGetParentScope):
(JSC::BytecodeGenerator::emitPopScope):
(JSC::BytecodeGenerator::emitDebugHook):
(JSC::BytecodeGenerator::pushFinallyContext):
(JSC::BytecodeGenerator::pushIteratorCloseContext):
(JSC::BytecodeGenerator::emitComplexPopScopes):
(JSC::BytecodeGenerator::emitPopScopes):
(JSC::BytecodeGenerator::popTryAndEmitCatch):
(JSC::BytecodeGenerator::calculateTargetScopeDepthForExceptionHandler):
(JSC::BytecodeGenerator::currentScopeDepth):
(JSC::BytecodeGenerator::emitThrowReferenceError):
(JSC::BytecodeGenerator::emitPushCatchScope):
(JSC::BytecodeGenerator::beginSwitch):
(JSC::BytecodeGenerator::emitReadOnlyExceptionIfNeeded):
(JSC::BytecodeGenerator::emitEnumeration):
* bytecompiler/BytecodeGenerator.h:
(JSC::Variable::Variable):
(JSC::Variable::isResolved):
(JSC::Variable::symbolTableConstantIndex):
(JSC::Variable::ident):
(JSC::BytecodeGenerator::ignoredResult):
(JSC::BytecodeGenerator::tempDestination):
(JSC::BytecodeGenerator::lastOpcodeID):
(JSC::BytecodeGenerator::makeFunction):
(JSC::BytecodeGenerator::symbolTable):
(JSC::BytecodeGenerator::shouldOptimizeLocals): Deleted.
(JSC::BytecodeGenerator::canOptimizeNonLocals): Deleted.
The heart of the changes in this patch are in the bytecode generator.
The bytecode generator now keeps a stack of tuples of
{symbol table, scope register, flag indicating catch or with scope, symbol table index in constant pool}
that models the runtime scope stack. This symbol table stack is used
in resolving local variables.

Also, the bytecode generator handles pushing and popping of lexical scopes.
This is relatively straight forward:
Captured 'let' variables end up in the JSLexicalEnvironment scope and non-captured
variables end up on the stack. Some trickiness is involved in generating
code for 'for' loops that have captured variables (I'm talking about variables in the loop
header, not the loop body). Each iteration of the for loop ends up with
its own JSLexicalEnvironment. Static code must be generated in such a way
to create this runtime behavior. This is done by emitting instructions to
push and pop a lexical scope at the end of each loop and copying values
from the previous loop's scope into the new scope. This code must also
ensure that each loop iteration's scope refers to the same underlying
SymbolTable so that no scope is accidentally mistaken as being a singleton scope.

When the debugger is enabled, all lexically defined variables will end up in the
JSLexicalEnvironment.

* bytecompiler/NodesCodegen.cpp:
(JSC::ResolveNode::emitBytecode):
(JSC::FunctionCallResolveNode::emitBytecode):
(JSC::PostfixNode::emitResolve):
(JSC::DeleteResolveNode::emitBytecode):
(JSC::TypeOfResolveNode::emitBytecode):
(JSC::PrefixNode::emitResolve):
(JSC::ReadModifyResolveNode::emitBytecode):
(JSC::AssignResolveNode::emitBytecode):
(JSC::BlockNode::emitBytecode):
(JSC::ExprStatementNode::emitBytecode):
(JSC::DeclarationStatement::emitBytecode):
(JSC::EmptyVarExpression::emitBytecode):
(JSC::EmptyLetExpression::emitBytecode):
(JSC::ForNode::emitBytecode):
(JSC::ForInNode::emitMultiLoopBytecode):
(JSC::ForOfNode::emitBytecode):
(JSC::SwitchNode::emitBytecode):
(JSC::BindingNode::bindValue):
(JSC::VarStatementNode::emitBytecode): Deleted.
* debugger/DebuggerCallFrame.cpp:
(JSC::DebuggerCallFrame::evaluate):
* debugger/DebuggerScope.cpp:
(JSC::DebuggerScope::getOwnPropertySlot):
(JSC::DebuggerScope::put):
* dfg/DFGByteCodeParser.cpp:
(JSC::DFG::ByteCodeParser::parseBlock):
* dfg/DFGCapabilities.cpp:
(JSC::DFG::capabilityLevel):
* dfg/DFGNode.h:
(JSC::DFG::Node::castConstant):
(JSC::DFG::Node::initializationValueForActivation):
(JSC::DFG::Node::containsMovHint):
* dfg/DFGObjectAllocationSinkingPhase.cpp:
CreateActivation nodes now have a second OpInfo that tracks the
initial value that needs to be placed in the activation. This initial value
is also used in allocation sinking to create proper bottom values for all
scope variables.

* dfg/DFGOperations.cpp:
* dfg/DFGOperations.h:
* dfg/DFGSpeculativeJIT.cpp:
(JSC::DFG::SpeculativeJIT::compileCreateActivation):
* dfg/DFGSpeculativeJIT.h:
(JSC::DFG::SpeculativeJIT::callOperation):
* ftl/FTLIntrinsicRepository.h:
* ftl/FTLLowerDFGToLLVM.cpp:
(JSC::FTL::DFG::LowerDFGToLLVM::compileCreateActivation):
(JSC::FTL::DFG::LowerDFGToLLVM::compileMaterializeCreateActivation):
* ftl/FTLOperations.cpp:
(JSC::FTL::operationMaterializeObjectInOSR):
* interpreter/Interpreter.cpp:
(JSC::Interpreter::execute):
* jit/CCallHelpers.h:
(JSC::CCallHelpers::setupArgumentsWithExecState):
* jit/JIT.cpp:
(JSC::JIT::privateCompileMainPass):
* jit/JIT.h:
* jit/JITInlines.h:
(JSC::JIT::callOperation):
* jit/JITOpcodes.cpp:
(JSC::JIT::emit_op_push_with_scope):
(JSC::JIT::compileOpStrictEq):
(JSC::JIT::emit_op_catch):
(JSC::JIT::emit_op_create_lexical_environment):
(JSC::JIT::emit_op_get_parent_scope):
(JSC::JIT::emit_op_switch_imm):
(JSC::JIT::emit_op_enter):
(JSC::JIT::emit_op_get_scope):
(JSC::JIT::emit_op_pop_scope): Deleted.
* jit/JITOpcodes32_64.cpp:
(JSC::JIT::emit_op_push_with_scope):
(JSC::JIT::emit_op_to_number):
(JSC::JIT::emit_op_catch):
(JSC::JIT::emit_op_create_lexical_environment):
(JSC::JIT::emit_op_get_parent_scope):
(JSC::JIT::emit_op_switch_imm):
(JSC::JIT::emit_op_enter):
(JSC::JIT::emit_op_get_scope):
(JSC::JIT::emit_op_pop_scope): Deleted.
* jit/JITOperations.cpp:
(JSC::canAccessArgumentIndexQuickly):
* jit/JITOperations.h:
* llint/LLIntSlowPaths.cpp:
(JSC::LLInt::LLINT_SLOW_PATH_DECL):
* llint/LLIntSlowPaths.h:
* llint/LowLevelInterpreter.asm:
* llint/LowLevelInterpreter32_64.asm:
* llint/LowLevelInterpreter64.asm:
* parser/ASTBuilder.h:
(JSC::ASTBuilder::createSourceElements):
(JSC::ASTBuilder::funcDeclarations):
(JSC::ASTBuilder::features):
(JSC::ASTBuilder::numConstants):
(JSC::ASTBuilder::createConditionalExpr):
(JSC::ASTBuilder::createAssignResolve):
(JSC::ASTBuilder::createClassDeclStatement):
(JSC::ASTBuilder::createBlockStatement):
(JSC::ASTBuilder::createIfStatement):
(JSC::ASTBuilder::createForLoop):
(JSC::ASTBuilder::createForInLoop):
(JSC::ASTBuilder::createForOfLoop):
(JSC::ASTBuilder::isBindingNode):
(JSC::ASTBuilder::createEmptyStatement):
(JSC::ASTBuilder::createDeclarationStatement):
(JSC::ASTBuilder::createVarStatement):
(JSC::ASTBuilder::createLetStatement):
(JSC::ASTBuilder::createEmptyVarExpression):
(JSC::ASTBuilder::createEmptyLetExpression):
(JSC::ASTBuilder::createReturnStatement):
(JSC::ASTBuilder::createTryStatement):
(JSC::ASTBuilder::createSwitchStatement):
(JSC::ASTBuilder::appendStatement):
(JSC::ASTBuilder::createCommaExpr):
(JSC::ASTBuilder::appendObjectPatternEntry):
(JSC::ASTBuilder::createBindingLocation):
(JSC::ASTBuilder::setEndOffset):
(JSC::ASTBuilder::Scope::Scope):
(JSC::ASTBuilder::makeAssignNode):
(JSC::ASTBuilder::varDeclarations): Deleted.
(JSC::ASTBuilder::addVar): Deleted.
* parser/Keywords.table:
* parser/NodeConstructors.h:
(JSC::ReadModifyResolveNode::ReadModifyResolveNode):
(JSC::AssignResolveNode::AssignResolveNode):
(JSC::ExprStatementNode::ExprStatementNode):
(JSC::DeclarationStatement::DeclarationStatement):
(JSC::EmptyVarExpression::EmptyVarExpression):
(JSC::EmptyLetExpression::EmptyLetExpression):
(JSC::IfElseNode::IfElseNode):
(JSC::WhileNode::WhileNode):
(JSC::ForNode::ForNode):
(JSC::CaseBlockNode::CaseBlockNode):
(JSC::SwitchNode::SwitchNode):
(JSC::ConstDeclNode::ConstDeclNode):
(JSC::BlockNode::BlockNode):
(JSC::EnumerationNode::EnumerationNode):
(JSC::ForInNode::ForInNode):
(JSC::ForOfNode::ForOfNode):
(JSC::ObjectPatternNode::create):
(JSC::BindingNode::create):
(JSC::BindingNode::BindingNode):
(JSC::VarStatementNode::VarStatementNode): Deleted.
* parser/Nodes.cpp:
(JSC::ScopeNode::ScopeNode):
(JSC::ScopeNode::singleStatement):
(JSC::ProgramNode::ProgramNode):
(JSC::EvalNode::EvalNode):
(JSC::FunctionNode::FunctionNode):
(JSC::FunctionNode::finishParsing):
(JSC::VariableEnvironmentNode::VariableEnvironmentNode):
* parser/Nodes.h:
(JSC::VariableEnvironmentNode::VariableEnvironmentNode):
(JSC::VariableEnvironmentNode::lexicalVariables):
(JSC::ScopeNode::usesThis):
(JSC::ScopeNode::needsActivationForMoreThanVariables):
(JSC::ScopeNode::needsActivation):
(JSC::ScopeNode::hasCapturedVariables):
(JSC::ScopeNode::captures):
(JSC::ScopeNode::varDeclarations):
(JSC::ScopeNode::functionStack):
(JSC::ScopeNode::neededConstants):
(JSC::ProgramNode::startColumn):
(JSC::ProgramNode::endColumn):
(JSC::EvalNode::startColumn):
(JSC::EvalNode::endColumn):
(JSC::BindingNode::boundProperty):
(JSC::BindingNode::divotStart):
(JSC::BindingNode::divotEnd):
(JSC::ScopeNode::capturedVariableCount): Deleted.
(JSC::ScopeNode::capturedVariables): Deleted.
(JSC::ScopeNode::varStack): Deleted.
There is a new class called 'VariableEnvironmentNode' that has the
necessary fields to model a lexical scope. Multiple AST nodes now
also inherit from VariableEnvironmentNode.

* parser/Parser.cpp:
(JSC::Parser<LexerType>::parseInner):
(JSC::Parser<LexerType>::didFinishParsing):
(JSC::Parser<LexerType>::parseStatementListItem):
(JSC::Parser<LexerType>::parseVariableDeclaration):
(JSC::Parser<LexerType>::parseWhileStatement):
(JSC::Parser<LexerType>::parseVariableDeclarationList):
(JSC::Parser<LexerType>::createBindingPattern):
(JSC::Parser<LexerType>::tryParseDestructuringPatternExpression):
(JSC::Parser<LexerType>::parseDestructuringPattern):
(JSC::Parser<LexerType>::parseConstDeclarationList):
(JSC::Parser<LexerType>::parseForStatement):
(JSC::Parser<LexerType>::parseBreakStatement):
(JSC::Parser<LexerType>::parseContinueStatement):
(JSC::Parser<LexerType>::parseSwitchStatement):
(JSC::Parser<LexerType>::parseTryStatement):
(JSC::Parser<LexerType>::parseBlockStatement):
(JSC::Parser<LexerType>::parseStatement):
(JSC::Parser<LexerType>::parseFunctionInfo):
(JSC::Parser<LexerType>::parseClassDeclaration):
(JSC::Parser<LexerType>::parseClass):
(JSC::Parser<LexerType>::parseExpressionOrLabelStatement):
(JSC::Parser<LexerType>::parseAssignmentExpression):
(JSC::Parser<LexerType>::parseGetterSetter):
(JSC::Parser<LexerType>::parsePrimaryExpression):
(JSC::Parser<LexerType>::parseVarDeclaration): Deleted.
(JSC::Parser<LexerType>::parseVarDeclarationList): Deleted.
* parser/Parser.h:
(JSC::Scope::Scope):
(JSC::Scope::setIsFunction):
(JSC::Scope::isFunction):
(JSC::Scope::isFunctionBoundary):
(JSC::Scope::setIsLexicalScope):
(JSC::Scope::isLexicalScope):
(JSC::Scope::declaredVariables):
(JSC::Scope::finalizeLexicalEnvironment):
(JSC::Scope::computeLexicallyCapturedVariablesAndPurgeCandidates):
(JSC::Scope::declareCallee):
(JSC::Scope::declareVariable):
(JSC::Scope::declareLexicalVariable):
(JSC::Scope::hasDeclaredVariable):
(JSC::Scope::hasLexicallyDeclaredVariable):
(JSC::Scope::hasDeclaredParameter):
(JSC::Scope::declareWrite):
(JSC::Scope::preventAllVariableDeclarations):
(JSC::Scope::preventVarDeclarations):
(JSC::Scope::allowsVarDeclarations):
(JSC::Scope::allowsLexicalDeclarations):
(JSC::Scope::declareParameter):
(JSC::Scope::declareBoundParameter):
(JSC::Scope::useVariable):
(JSC::Scope::setNeedsFullActivation):
(JSC::Scope::needsFullActivation):
(JSC::Scope::hasDirectSuper):
(JSC::Scope::setNeedsSuperBinding):
(JSC::Scope::collectFreeVariables):
(JSC::Scope::getCapturedVars):
(JSC::Scope::copyCapturedVariablesToVector):
(JSC::Parser::AutoCleanupLexicalScope::AutoCleanupLexicalScope):
(JSC::Parser::AutoCleanupLexicalScope::~AutoCleanupLexicalScope):
(JSC::Parser::AutoCleanupLexicalScope::setIsValid):
(JSC::Parser::AutoCleanupLexicalScope::isValid):
(JSC::Parser::AutoCleanupLexicalScope::setPopped):
(JSC::Parser::AutoCleanupLexicalScope::scope):
(JSC::Parser::currentScope):
(JSC::Parser::pushScope):
(JSC::Parser::popScopeInternal):
(JSC::Parser::popScope):
(JSC::Parser::declareVariable):
(JSC::Parser::hasDeclaredVariable):
(JSC::Parser::hasDeclaredParameter):
(JSC::Parser::declareWrite):
(JSC::Parser::findCachedFunctionInfo):
(JSC::Parser::isFunctionBodyNode):
(JSC::Parser::continueIsValid):
(JSC::Parser::pushLabel):
(JSC::Parser::popLabel):
(JSC::Parser::getLabel):
(JSC::Parser::isLETMaskedAsIDENT):
(JSC::Parser<LexerType>::parse):
(JSC::Scope::preventNewDecls): Deleted.
(JSC::Scope::allowsNewDecls): Deleted.
(JSC::Scope::getCapturedVariables): Deleted.
There are basic parser changes that now allow for the 'let'
keyword. The trickiest change is how we will still treat 'let'
as an identifier for sloppy-mode code sometimes. For example,
"var let = ..." is allowed but "let let" or "const let" is not.

The most significant change to the parser made for this patch
is appropriating the Scope struct to also also model a lexical
scope. Changes were made in how we track captured variables to
account for this. In general, I think some of this code could
benefit from a slight refactoring to make things cleaner.

* parser/ParserTokens.h:
* parser/SyntaxChecker.h:
(JSC::SyntaxChecker::createNewExpr):
(JSC::SyntaxChecker::createConditionalExpr):
(JSC::SyntaxChecker::createAssignResolve):
(JSC::SyntaxChecker::createEmptyVarExpression):
(JSC::SyntaxChecker::createEmptyLetExpression):
(JSC::SyntaxChecker::createClassExpr):
(JSC::SyntaxChecker::createClassDeclStatement):
(JSC::SyntaxChecker::createBlockStatement):
(JSC::SyntaxChecker::createExprStatement):
(JSC::SyntaxChecker::createIfStatement):
(JSC::SyntaxChecker::createForLoop):
(JSC::SyntaxChecker::createForInLoop):
(JSC::SyntaxChecker::createForOfLoop):
(JSC::SyntaxChecker::createEmptyStatement):
(JSC::SyntaxChecker::createVarStatement):
(JSC::SyntaxChecker::createLetStatement):
(JSC::SyntaxChecker::createReturnStatement):
(JSC::SyntaxChecker::createBreakStatement):
(JSC::SyntaxChecker::createContinueStatement):
(JSC::SyntaxChecker::createTryStatement):
(JSC::SyntaxChecker::createSwitchStatement):
(JSC::SyntaxChecker::createWhileStatement):
(JSC::SyntaxChecker::createWithStatement):
(JSC::SyntaxChecker::createDoWhileStatement):
(JSC::SyntaxChecker::createGetterOrSetterProperty):
(JSC::SyntaxChecker::appendStatement):
(JSC::SyntaxChecker::combineCommaNodes):
(JSC::SyntaxChecker::evalCount):
(JSC::SyntaxChecker::appendBinaryExpressionInfo):
(JSC::SyntaxChecker::operatorStackPop):
(JSC::SyntaxChecker::addVar): Deleted.
* parser/VariableEnvironment.cpp: Added.
(JSC::VariableEnvironment::markVariableAsCapturedIfDefined):
(JSC::VariableEnvironment::markVariableAsCaptured):
(JSC::VariableEnvironment::markAllVariablesAsCaptured):
(JSC::VariableEnvironment::hasCapturedVariables):
(JSC::VariableEnvironment::captures):
(JSC::VariableEnvironment::swap):
* parser/VariableEnvironment.h: Added.
(JSC::VariableEnvironmentEntry::isCaptured):
(JSC::VariableEnvironmentEntry::isConstant):
(JSC::VariableEnvironmentEntry::isVar):
(JSC::VariableEnvironmentEntry::isLet):
(JSC::VariableEnvironmentEntry::setIsCaptured):
(JSC::VariableEnvironmentEntry::setIsConstant):
(JSC::VariableEnvironmentEntry::setIsVar):
(JSC::VariableEnvironmentEntry::setIsLet):
(JSC::VariableEnvironmentEntry::clearIsVar):
(JSC::VariableEnvironment::begin):
(JSC::VariableEnvironment::end):
(JSC::VariableEnvironment::add):
(JSC::VariableEnvironment::size):
(JSC::VariableEnvironment::contains):
(JSC::VariableEnvironment::remove):
VariableEnvironment is a new class that keeps track
of the static environment in the parser and the bytecode generator.
VariableEnvironment behaves like SymbolTable but for the bytecode generator.
It keeps track of variable types, i.e, if a variable is a "var", "let", "const"
and whether or not its captured.

* runtime/CodeCache.cpp:
(JSC::CodeCache::getGlobalCodeBlock):
(JSC::CodeCache::getProgramCodeBlock):
(JSC::CodeCache::getEvalCodeBlock):
(JSC::CodeCache::getFunctionExecutableFromGlobalCode):
* runtime/CodeCache.h:
(JSC::CodeCache::clear):
* runtime/CommonSlowPaths.cpp:
(JSC::SLOW_PATH_DECL):
* runtime/CommonSlowPaths.h:
* runtime/ExceptionHelpers.cpp:
(JSC::createErrorForInvalidGlobalAssignment):
(JSC::createTDZError):
(JSC::throwOutOfMemoryError):
* runtime/ExceptionHelpers.h:
* runtime/Executable.cpp:
(JSC::EvalExecutable::create):
(JSC::ProgramExecutable::initializeGlobalProperties):
* runtime/Executable.h:
* runtime/JSCJSValue.h:
(JSC::jsUndefined):
(JSC::jsTDZValue):
(JSC::jsBoolean):
* runtime/JSEnvironmentRecord.h:
(JSC::JSEnvironmentRecord::finishCreationUninitialized):
(JSC::JSEnvironmentRecord::finishCreation):
* runtime/JSGlobalObject.cpp:
(JSC::JSGlobalObject::createProgramCodeBlock):
(JSC::JSGlobalObject::createEvalCodeBlock):
* runtime/JSGlobalObject.h:
(JSC::JSGlobalObject::weakRandomInteger):
* runtime/JSGlobalObjectFunctions.cpp:
(JSC::globalFuncEval):
* runtime/JSLexicalEnvironment.cpp:
(JSC::JSLexicalEnvironment::symbolTableGet):
* runtime/JSLexicalEnvironment.h:
(JSC::JSLexicalEnvironment::create):
* runtime/JSScope.cpp:
(JSC::JSScope::resolve):
(JSC::JSScope::abstractResolve):
(JSC::JSScope::collectVariablesUnderTDZ):
(JSC::JSScope::isLexicalScope):
(JSC::resolveModeName):
* runtime/JSScope.h:
* runtime/PropertySlot.h:
(JSC::PropertySlot::setValue):
* runtime/SymbolTable.cpp:
(JSC::SymbolTable::SymbolTable):
(JSC::SymbolTable::cloneScopePart):
* runtime/SymbolTable.h:
SymbolTable now uses an extra bit to know if it corresponds
to a "let"-like environment or not.

* runtime/WriteBarrier.h:
(JSC::WriteBarrierBase<Unknown>::get):
(JSC::WriteBarrierBase<Unknown>::clear):
(JSC::WriteBarrierBase<Unknown>::setUndefined):
(JSC::WriteBarrierBase<Unknown>::setStartingValue):
(JSC::WriteBarrierBase<Unknown>::isNumber):
(JSC::WriteBarrierBase<Unknown>::isObject):
(JSC::WriteBarrierBase<Unknown>::isNull):
* tests/stress/activation-sink-default-value-tdz-error.js: Added.
(shouldThrowTDZ):
(bar):
(foo.cap):
* tests/stress/activation-sink-osrexit-default-value-tdz-error.js: Added.
(shouldThrowTDZ):
(bar):
* tests/stress/lexical-let-and-with-statement.js: Added.
(truth):
(assert):
(.):
* tests/stress/lexical-let-exception-handling.js: Added.
(truth):
(assert):
(.):
* tests/stress/lexical-let-global-not-captured-variables.js: Added.
(truth):
(assert):
(foo):
(.let.capY):
* tests/stress/lexical-let-loop-semantics.js: Added.
(truth):
(assert):
(shouldThrowTDZ):
(.):
* tests/stress/lexical-let-not-strict-mode.js: Added.
(truth):
(assert):
(shouldThrowTDZ):
(.):
* tests/stress/lexical-let-semantics.js: Added.
(truth):
(assert):
(let.globalFunction):
(let.retGlobalNumberCaptured):
(let.setGlobalNumberCaptured):
(.):
* tests/stress/lexical-let-tdz.js: Added.
(truth):
(assert):
(shouldThrowTDZ):
(.):

LayoutTests:

* js/dom/reserved-words-as-property-expected.txt:
* js/keywords-and-reserved_words-expected.txt:
* js/let-syntax-expected.txt: Added.
* js/let-syntax.html: Added.
* js/reserved-words-strict-expected.txt:
* js/script-tests/keywords-and-reserved_words.js:
* js/script-tests/let-syntax.js: Added.
(truth):
(assert):
(hasSyntaxError):
(shouldHaveSyntaxError):
(shouldNotHaveSyntaxError):
(shouldHaveSyntaxErrorStrictOnly):
* js/script-tests/reserved-words-strict.js:
* js/script-tests/statement-list-item-syntax-errors.js:
(testSyntax):
(runTests):
* js/statement-list-item-syntax-errors-expected.txt:

git-svn-id: https://svn.webkit.org/repository/webkit/trunk@186860 268f45cc-cd09-0410-ab3c-d52691b4dbfc
95 files changed:
LayoutTests/ChangeLog
LayoutTests/js/dom/reserved-words-as-property-expected.txt
LayoutTests/js/keywords-and-reserved_words-expected.txt
LayoutTests/js/let-syntax-expected.txt [new file with mode: 0644]
LayoutTests/js/let-syntax.html [new file with mode: 0644]
LayoutTests/js/reserved-words-strict-expected.txt
LayoutTests/js/script-tests/keywords-and-reserved_words.js
LayoutTests/js/script-tests/let-syntax.js [new file with mode: 0644]
LayoutTests/js/script-tests/reserved-words-strict.js
LayoutTests/js/script-tests/statement-list-item-syntax-errors.js
LayoutTests/js/statement-list-item-syntax-errors-expected.txt
Source/JavaScriptCore/CMakeLists.txt
Source/JavaScriptCore/ChangeLog
Source/JavaScriptCore/JavaScriptCore.vcxproj/JavaScriptCore.vcxproj
Source/JavaScriptCore/JavaScriptCore.vcxproj/JavaScriptCore.vcxproj.filters
Source/JavaScriptCore/JavaScriptCore.xcodeproj/project.pbxproj
Source/JavaScriptCore/builtins/BuiltinExecutables.cpp
Source/JavaScriptCore/bytecode/BytecodeList.json
Source/JavaScriptCore/bytecode/BytecodeUseDef.h
Source/JavaScriptCore/bytecode/CodeBlock.cpp
Source/JavaScriptCore/bytecode/CodeBlock.h
Source/JavaScriptCore/bytecode/EvalCodeCache.h
Source/JavaScriptCore/bytecode/UnlinkedCodeBlock.cpp
Source/JavaScriptCore/bytecode/UnlinkedCodeBlock.h
Source/JavaScriptCore/bytecompiler/BytecodeGenerator.cpp
Source/JavaScriptCore/bytecompiler/BytecodeGenerator.h
Source/JavaScriptCore/bytecompiler/NodesCodegen.cpp
Source/JavaScriptCore/debugger/DebuggerCallFrame.cpp
Source/JavaScriptCore/debugger/DebuggerScope.cpp
Source/JavaScriptCore/dfg/DFGByteCodeParser.cpp
Source/JavaScriptCore/dfg/DFGCapabilities.cpp
Source/JavaScriptCore/dfg/DFGNode.h
Source/JavaScriptCore/dfg/DFGObjectAllocationSinkingPhase.cpp
Source/JavaScriptCore/dfg/DFGOperations.cpp
Source/JavaScriptCore/dfg/DFGOperations.h
Source/JavaScriptCore/dfg/DFGSpeculativeJIT.cpp
Source/JavaScriptCore/dfg/DFGSpeculativeJIT.h
Source/JavaScriptCore/ftl/FTLIntrinsicRepository.h
Source/JavaScriptCore/ftl/FTLLowerDFGToLLVM.cpp
Source/JavaScriptCore/ftl/FTLOperations.cpp
Source/JavaScriptCore/interpreter/Interpreter.cpp
Source/JavaScriptCore/jit/CCallHelpers.h
Source/JavaScriptCore/jit/JIT.cpp
Source/JavaScriptCore/jit/JIT.h
Source/JavaScriptCore/jit/JITInlines.h
Source/JavaScriptCore/jit/JITOpcodes.cpp
Source/JavaScriptCore/jit/JITOpcodes32_64.cpp
Source/JavaScriptCore/jit/JITOperations.cpp
Source/JavaScriptCore/jit/JITOperations.h
Source/JavaScriptCore/llint/LLIntSlowPaths.cpp
Source/JavaScriptCore/llint/LLIntSlowPaths.h
Source/JavaScriptCore/llint/LowLevelInterpreter.asm
Source/JavaScriptCore/llint/LowLevelInterpreter32_64.asm
Source/JavaScriptCore/llint/LowLevelInterpreter64.asm
Source/JavaScriptCore/parser/ASTBuilder.h
Source/JavaScriptCore/parser/Keywords.table
Source/JavaScriptCore/parser/NodeConstructors.h
Source/JavaScriptCore/parser/Nodes.cpp
Source/JavaScriptCore/parser/Nodes.h
Source/JavaScriptCore/parser/Parser.cpp
Source/JavaScriptCore/parser/Parser.h
Source/JavaScriptCore/parser/ParserTokens.h
Source/JavaScriptCore/parser/SyntaxChecker.h
Source/JavaScriptCore/parser/VariableEnvironment.cpp [new file with mode: 0644]
Source/JavaScriptCore/parser/VariableEnvironment.h [new file with mode: 0644]
Source/JavaScriptCore/runtime/CodeCache.cpp
Source/JavaScriptCore/runtime/CodeCache.h
Source/JavaScriptCore/runtime/CommonSlowPaths.cpp
Source/JavaScriptCore/runtime/CommonSlowPaths.h
Source/JavaScriptCore/runtime/ExceptionHelpers.cpp
Source/JavaScriptCore/runtime/ExceptionHelpers.h
Source/JavaScriptCore/runtime/Executable.cpp
Source/JavaScriptCore/runtime/Executable.h
Source/JavaScriptCore/runtime/JSCJSValue.h
Source/JavaScriptCore/runtime/JSEnvironmentRecord.h
Source/JavaScriptCore/runtime/JSGlobalObject.cpp
Source/JavaScriptCore/runtime/JSGlobalObject.h
Source/JavaScriptCore/runtime/JSGlobalObjectFunctions.cpp
Source/JavaScriptCore/runtime/JSLexicalEnvironment.cpp
Source/JavaScriptCore/runtime/JSLexicalEnvironment.h
Source/JavaScriptCore/runtime/JSScope.cpp
Source/JavaScriptCore/runtime/JSScope.h
Source/JavaScriptCore/runtime/PropertySlot.h
Source/JavaScriptCore/runtime/SymbolTable.cpp
Source/JavaScriptCore/runtime/SymbolTable.h
Source/JavaScriptCore/runtime/WriteBarrier.h
Source/JavaScriptCore/tests/stress/activation-sink-default-value-tdz-error.js [new file with mode: 0644]
Source/JavaScriptCore/tests/stress/activation-sink-osrexit-default-value-tdz-error.js [new file with mode: 0644]
Source/JavaScriptCore/tests/stress/lexical-let-and-with-statement.js [new file with mode: 0644]
Source/JavaScriptCore/tests/stress/lexical-let-exception-handling.js [new file with mode: 0644]
Source/JavaScriptCore/tests/stress/lexical-let-global-not-captured-variables.js [new file with mode: 0644]
Source/JavaScriptCore/tests/stress/lexical-let-loop-semantics.js [new file with mode: 0644]
Source/JavaScriptCore/tests/stress/lexical-let-not-strict-mode.js [new file with mode: 0644]
Source/JavaScriptCore/tests/stress/lexical-let-semantics.js [new file with mode: 0644]
Source/JavaScriptCore/tests/stress/lexical-let-tdz.js [new file with mode: 0644]