[ES6] Add support for block scope const
https://bugs.webkit.org/show_bug.cgi?id=31813
Reviewed by Filip Pizlo.
Source/JavaScriptCore:
'const' is now implemented in an ES6 spec compliant manner.
'const' variables are always block scoped and always live
either on the stack or in a JSLexicalEnvironment. 'const'
variables never live on the global object.
Inside the BytecodeGenerator, when assigning to a stack
'const' variable or a LocalClosureVar 'const' variable,
we will emit code that just throws a type error.
When assigning to a ClosureVar const variable, CodeBlock linking
will ensure that we perform a dynamic lookup of that variable so
that put_to_scope's slow path throws a type error.
The old 'const' implementation has been removed in this patch.
- bytecode/BytecodeList.json:
- bytecode/BytecodeUseDef.h:
(JSC::computeUsesForBytecodeOffset):
(JSC::computeDefsForBytecodeOffset):
(JSC::CodeBlock::dumpBytecode):
(JSC::CodeBlock::CodeBlock):
- bytecompiler/BytecodeGenerator.cpp:
(JSC::BytecodeGenerator::BytecodeGenerator):
(JSC::BytecodeGenerator::pushLexicalScope):
(JSC::BytecodeGenerator::prepareLexicalScopeForNextForLoopIteration):
(JSC::BytecodeGenerator::variable):
(JSC::BytecodeGenerator::variableForLocalEntry):
(JSC::BytecodeGenerator::createVariable):
(JSC::BytecodeGenerator::emitResolveScope):
(JSC::BytecodeGenerator::emitInstanceOf):
(JSC::BytecodeGenerator::emitGetById):
(JSC::BytecodeGenerator::isArgumentNumber):
(JSC::BytecodeGenerator::emitReadOnlyExceptionIfNeeded):
(JSC::BytecodeGenerator::emitEnumeration):
(JSC::BytecodeGenerator::variablePerSymbolTable): Deleted.
(JSC::BytecodeGenerator::emitInitGlobalConst): Deleted.
- bytecompiler/BytecodeGenerator.h:
(JSC::Variable::Variable):
(JSC::Variable::isReadOnly):
(JSC::Variable::isSpecial):
(JSC::Variable::isConst):
(JSC::BytecodeGenerator::thisRegister):
(JSC::BytecodeGenerator::emitTypeOf):
(JSC::BytecodeGenerator::emitIn):
- bytecompiler/NodesCodegen.cpp:
(JSC::PostfixNode::emitResolve):
(JSC::PrefixNode::emitResolve):
(JSC::ReadModifyResolveNode::emitBytecode):
(JSC::AssignResolveNode::emitBytecode):
(JSC::CommaNode::emitBytecode):
(JSC::BindingNode::bindValue):
(JSC::ConstDeclNode::emitCodeSingle): Deleted.
(JSC::ConstDeclNode::emitBytecode): Deleted.
(JSC::ConstStatementNode::emitBytecode): Deleted.
- dfg/DFGByteCodeParser.cpp:
(JSC::DFG::ByteCodeParser::parseBlock):
(JSC::DFG::capabilityLevel):
(JSC::JIT::privateCompileMainPass):
- jit/JIT.h:
- jit/JITPropertyAccess.cpp:
(JSC::JIT::emit_op_put_to_arguments):
(JSC::JIT::emit_op_init_global_const): Deleted.
- jit/JITPropertyAccess32_64.cpp:
(JSC::JIT::emit_op_put_to_arguments):
(JSC::JIT::emit_op_init_global_const): Deleted.
- llint/LowLevelInterpreter.asm:
- llint/LowLevelInterpreter32_64.asm:
- llint/LowLevelInterpreter64.asm:
- parser/ASTBuilder.h:
(JSC::ASTBuilder::createDeclarationStatement):
(JSC::ASTBuilder::createEmptyVarExpression):
(JSC::ASTBuilder::createDebugger):
(JSC::ASTBuilder::appendStatement):
(JSC::ASTBuilder::createVarStatement): Deleted.
(JSC::ASTBuilder::createLetStatement): Deleted.
(JSC::ASTBuilder::createConstStatement): Deleted.
(JSC::ASTBuilder::appendConstDecl): Deleted.
- parser/NodeConstructors.h:
(JSC::CommaNode::CommaNode):
(JSC::SourceElements::SourceElements):
(JSC::SwitchNode::SwitchNode):
(JSC::BlockNode::BlockNode):
(JSC::ConstStatementNode::ConstStatementNode): Deleted.
(JSC::ConstDeclNode::ConstDeclNode): Deleted.
(JSC::ConstDeclNode::hasInitializer): Deleted.
(JSC::ConstDeclNode::ident): Deleted.
(JSC::Parser<LexerType>::parseStatementListItem):
(JSC::Parser<LexerType>::parseVariableDeclaration):
(JSC::Parser<LexerType>::parseWhileStatement):
(JSC::Parser<LexerType>::parseVariableDeclarationList):
(JSC::Parser<LexerType>::createBindingPattern):
(JSC::Parser<LexerType>::parseDestructuringPattern):
(JSC::Parser<LexerType>::parseDefaultValueForDestructuringPattern):
(JSC::Parser<LexerType>::parseForStatement):
(JSC::Parser<LexerType>::parseTryStatement):
(JSC::Parser<LexerType>::parseFunctionInfo):
(JSC::Parser<LexerType>::parseFunctionDeclaration):
(JSC::Parser<LexerType>::parseClass):
(JSC::Parser<LexerType>::parseConstDeclaration): Deleted.
(JSC::Parser<LexerType>::parseConstDeclarationList): Deleted.
(JSC::isEvalNode):
(JSC::isEvalNode<EvalNode>):
(JSC::isArguments):
(JSC::isEval):
(JSC::isEvalOrArgumentsIdentifier):
(JSC::Scope::Scope):
(JSC::Scope::declareCallee):
(JSC::Scope::declareVariable):
(JSC::Scope::declareLexicalVariable):
(JSC::Scope::hasDeclaredVariable):
(JSC::Scope::allowsVarDeclarations):
(JSC::Scope::allowsLexicalDeclarations):
(JSC::Scope::declareParameter):
(JSC::Scope::declareBoundParameter):
(JSC::Parser::destructuringKindFromDeclarationType):
(JSC::Parser::assignmentContextFromDeclarationType):
(JSC::Parser::isEvalOrArguments):
(JSC::Parser::currentScope):
(JSC::Parser::popScope):
(JSC::Parser::declareVariable):
(JSC::Parser::hasDeclaredVariable):
(JSC::Parser::setStrictMode):
(JSC::Parser::strictMode):
(JSC::Parser::isValidStrictMode):
(JSC::Parser::declareParameter):
(JSC::Parser::declareBoundParameter):
(JSC::Parser::breakIsValid):
(JSC::SyntaxChecker::createForInLoop):
(JSC::SyntaxChecker::createForOfLoop):
(JSC::SyntaxChecker::createEmptyStatement):
(JSC::SyntaxChecker::createDeclarationStatement):
(JSC::SyntaxChecker::createReturnStatement):
(JSC::SyntaxChecker::createBreakStatement):
(JSC::SyntaxChecker::createVarStatement): Deleted.
(JSC::SyntaxChecker::createLetStatement): Deleted.
- parser/VariableEnvironment.h:
(JSC::VariableEnvironmentEntry::isCaptured):
(JSC::VariableEnvironmentEntry::isConst):
(JSC::VariableEnvironmentEntry::isVar):
(JSC::VariableEnvironmentEntry::isLet):
(JSC::VariableEnvironmentEntry::setIsCaptured):
(JSC::VariableEnvironmentEntry::setIsConst):
(JSC::VariableEnvironmentEntry::setIsVar):
(JSC::VariableEnvironmentEntry::setIsLet):
(JSC::VariableEnvironmentEntry::isConstant): Deleted.
(JSC::VariableEnvironmentEntry::setIsConstant): Deleted.
(JSC::ProgramExecutable::initializeGlobalProperties):
- runtime/JSGlobalObject.cpp:
(JSC::JSGlobalObject::defineOwnProperty):
(JSC::JSGlobalObject::addGlobalVar):
(JSC::JSGlobalObject::addFunction):
(JSC::lastInPrototypeChain):
- runtime/JSGlobalObject.h:
(JSC::JSGlobalObject::finishCreation):
(JSC::JSGlobalObject::addVar):
(JSC::JSGlobalObject::addConst): Deleted.
- runtime/JSLexicalEnvironment.cpp:
(JSC::JSLexicalEnvironment::symbolTablePut):
- tests/stress/const-and-with-statement.js: Added.
(truth):
(assert):
(shouldThrowInvalidConstAssignment):
(.):
- tests/stress/const-exception-handling.js: Added.
(truth):
(assert):
(.):
- tests/stress/const-loop-semantics.js: Added.
(truth):
(assert):
(shouldThrowInvalidConstAssignment):
(.):
- tests/stress/const-not-strict-mode.js: Added.
(truth):
(assert):
(shouldThrowTDZ):
(.):
- tests/stress/const-semantics.js: Added.
(truth):
(assert):
(shouldThrowInvalidConstAssignment):
(.):
- tests/stress/const-tdz.js: Added.
(truth):
(assert):
(shouldThrowTDZ):
(.):
Source/WebInspectorUI:
"const" variables do not live on the global object and are only
accessible within the "Program" they're defined in. Therefore,
the WebInspector global must be defined as "var" and not "const".
- UserInterface/Base/WebInspector.js:
LayoutTests:
"const" variables do not live on the global object. They
are only available in the "Program" (read: JavaScript file or
script tag) that they're defined in. Tests have been updated
accordingly to switch the "const" variables assumed to be globals
into "var"s. "var" declared variables in the top level scope
of a program do live on the global object.
- fast/canvas/webgl/compressed-tex-image.html:
- fast/dom/event-handler-attributes.html:
- fast/forms/listbox-visible-size.html:
- js/arguments-expected.txt:
- js/arrowfunction-syntax-errors-expected.txt:
- js/const-expected.txt:
- js/const-without-initializer-expected.txt:
- js/constant-count-expected.txt:
- js/dom/inc-const-valueOf-expected.txt:
- js/dom/script-tests/inc-const-valueOf.js:
(testPreIncConstVarWithAssign):
- js/function-toString-parentheses-expected.txt:
- js/kde/const-expected.txt:
- js/kde/resources/const.js:
- js/parser-syntax-check-expected.txt:
- js/script-tests/arguments.js:
(argumentsVarUndefined):
(argumentsConst):
(argumentCalleeInException):
(argumentsConstUndefined): Deleted.
- js/script-tests/class-syntax-declaration.js:
(A):
- js/script-tests/class-syntax-expression.js:
- js/script-tests/const-without-initializer.js:
- js/script-tests/const.js:
(shouldThrowInvalidConstAssignment):
(assert):
(f):
(tryCatch1):
(tryCatch2):
(with1):
(with2):
(.):
- js/script-tests/constant-count.js:
(f):
- js/script-tests/function-dot-arguments.js:
(assignConstInitTest2.g):
(assignConstInitTest2):
- js/script-tests/function-toString-parentheses.js:
- js/script-tests/parser-syntax-check.js:
- sputnik/Conformance/07_Lexical_Conventions/7.5_Tokens/7.5.3_Future_Reserved_Words/S7.5.3_A1.6-expected.txt:
- sputnik/Conformance/07_Lexical_Conventions/7.8_Literals/7.8.5_Regular_Expression_Literals/S7.8.5_A3.1_T7-expected.txt:
- sputnik/Conformance/07_Lexical_Conventions/7.8_Literals/7.8.5_Regular_Expression_Literals/S7.8.5_A3.1_T8-expected.txt:
- sputnik/Conformance/07_Lexical_Conventions/7.8_Literals/7.8.5_Regular_Expression_Literals/S7.8.5_A3.1_T9-expected.txt:
- sputnik/Conformance/08_Types/8.4_The_String_Type/S8.4_A13_T3-expected.txt:
- sputnik/Conformance/08_Types/8.4_The_String_Type/S8.4_A14_T3-expected.txt:
- sputnik/Conformance/12_Statement/12.2_Variable_Statement/S12.2_A8_T1-expected.txt:
- sputnik/Conformance/12_Statement/12.2_Variable_Statement/S12.2_A8_T2-expected.txt:
- sputnik/Conformance/12_Statement/12.2_Variable_Statement/S12.2_A8_T3-expected.txt:
- sputnik/Conformance/12_Statement/12.2_Variable_Statement/S12.2_A8_T4-expected.txt:
- sputnik/Conformance/12_Statement/12.2_Variable_Statement/S12.2_A8_T6-expected.txt:
- sputnik/Conformance/12_Statement/12.2_Variable_Statement/S12.2_A8_T7-expected.txt:
- sputnik/Conformance/12_Statement/12.2_Variable_Statement/S12.2_A8_T8-expected.txt:
- transforms/3d/hit-testing/composited-hit-test.html:
- transforms/3d/hit-testing/coplanar-with-camera.html:
- transforms/3d/hit-testing/hover-rotated-negative-z.html:
- transforms/3d/hit-testing/hover-rotated-with-children-negative-z.html:
- transforms/3d/hit-testing/negative-zoffset-hit-test.html:
- transforms/3d/hit-testing/overlapping-layers-hit-test.html:
- transforms/3d/hit-testing/perspective-clipped.html:
- transforms/3d/hit-testing/rotated-hit-test-with-child.html:
- transforms/3d/hit-testing/rotated-hit-test.html:
- transforms/3d/hit-testing/rotated-hit-test2.html:
- transitions/resources/transition-test-helpers.js:
(roundNumber):
