Source/JavaScriptCore/runtime/ProgramExecutable.cpp - WebKit - Git at Google

 /*
  * Copyright (C) 2009-2019 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 "BatchedTransitionOptimizer.h"
 #include "CodeCache.h"
 #include "Debugger.h"

 namespace JSC {

 const ClassInfo ProgramExecutable::s_info = { "ProgramExecutable", &Base::s_info, nullptr, nullptr, CREATE_METHOD_TABLE(ProgramExecutable) };

 ProgramExecutable::ProgramExecutable(JSGlobalObject* globalObject, const SourceCode& source)
     : Base(globalObject->vm().programExecutableStructure.get(), globalObject->vm(), source, false, DerivedContextType::None, false, false, EvalContextType::None, NoIntrinsic)
 {
     ASSERT(source.provider()->sourceType() == SourceProviderSourceType::Program);
     VM& vm = globalObject->vm();
     if (vm.typeProfiler() || vm.controlFlowProfiler())
         vm.functionHasExecutedCache()->insertUnexecutedRange(sourceID(), typeProfilingStartOffset(vm), typeProfilingEndOffset(vm));
 }

 void ProgramExecutable::destroy(JSCell* cell)
 {
     static_cast<ProgramExecutable*>(cell)->ProgramExecutable::~ProgramExecutable();
 }

 // http://www.ecma-international.org/ecma-262/6.0/index.html#sec-hasrestrictedglobalproperty
 enum class GlobalPropertyLookUpStatus {
     NotFound,
     Configurable,
     NonConfigurable,
 };
 static GlobalPropertyLookUpStatus hasRestrictedGlobalProperty(JSGlobalObject* globalObject, PropertyName propertyName)
 {
     PropertyDescriptor descriptor;
     if (!globalObject->getOwnPropertyDescriptor(globalObject, propertyName, descriptor))
         return GlobalPropertyLookUpStatus::NotFound;
     if (descriptor.configurable())
         return GlobalPropertyLookUpStatus::Configurable;
     return GlobalPropertyLookUpStatus::NonConfigurable;
 }

 JSObject* ProgramExecutable::initializeGlobalProperties(VM& vm, JSGlobalObject* globalObject, JSScope* scope)
 {
     auto throwScope = DECLARE_THROW_SCOPE(vm);
     RELEASE_ASSERT(scope);
     ASSERT(globalObject == scope->globalObject(vm));
     RELEASE_ASSERT(globalObject);
     ASSERT(&globalObject->vm() == &vm);

     ParserError error;
     JSParserStrictMode strictMode = isInStrictContext() ? JSParserStrictMode::Strict : JSParserStrictMode::NotStrict;
     OptionSet<CodeGenerationMode> codeGenerationMode = globalObject->defaultCodeGenerationMode();
     UnlinkedProgramCodeBlock* unlinkedCodeBlock = vm.codeCache()->getUnlinkedProgramCodeBlock(
         vm, this, source(), strictMode, codeGenerationMode, error);

     if (globalObject->hasDebugger())
         globalObject->debugger()->sourceParsed(globalObject, source().provider(), error.line(), error.message());

     if (error.isValid())
         return error.toErrorObject(globalObject, source());

     JSValue nextPrototype = globalObject->getPrototypeDirect(vm);
     while (nextPrototype && nextPrototype.isObject()) {
         if (UNLIKELY(asObject(nextPrototype)->type() == ProxyObjectType))
             return createTypeError(globalObject, "Proxy is not allowed in the global prototype chain."_s);
         nextPrototype = asObject(nextPrototype)->getPrototypeDirect(vm);
     }

     JSGlobalLexicalEnvironment* globalLexicalEnvironment = globalObject->globalLexicalEnvironment();
     const VariableEnvironment& variableDeclarations = unlinkedCodeBlock->variableDeclarations();
     const VariableEnvironment& lexicalDeclarations = unlinkedCodeBlock->lexicalDeclarations();
     // The ES6 spec says that no vars/global properties/let/const can be duplicated in the global scope.
     // This carried out section 15.1.8 of the ES6 spec: http://www.ecma-international.org/ecma-262/6.0/index.html#sec-globaldeclarationinstantiation
     {
         // Check for intersection of "var" and "let"/"const"/"class"
         for (auto& entry : lexicalDeclarations) {
             if (variableDeclarations.contains(entry.key))
                 return createSyntaxError(globalObject, makeString("Can't create duplicate variable: '", String(entry.key.get()), "'"));
         }

         // Check if any new "let"/"const"/"class" will shadow any pre-existing global property names (with configurable = false), or "var"/"let"/"const" variables.
         // It's an error to introduce a shadow.
         for (auto& entry : lexicalDeclarations) {
             // The ES6 spec says that RestrictedGlobalProperty can't be shadowed.
             GlobalPropertyLookUpStatus status = hasRestrictedGlobalProperty(globalObject, entry.key.get());
             RETURN_IF_EXCEPTION(throwScope, nullptr);
             switch (status) {
             case GlobalPropertyLookUpStatus::NonConfigurable:
                 return createSyntaxError(globalObject, makeString("Can't create duplicate variable that shadows a global property: '", String(entry.key.get()), "'"));
             case GlobalPropertyLookUpStatus::Configurable:
                 // Lexical bindings can shadow global properties if the given property's attribute is configurable.
                 // https://tc39.github.io/ecma262/#sec-globaldeclarationinstantiation step 5-c, `hasRestrictedGlobal` becomes false
                 // However we may emit GlobalProperty look up in bytecodes already and it may cache the value for the global scope.
                 // To make it invalid,
                 // 1. In LLInt and Baseline, we bump the global lexical binding epoch and it works.
                 // 3. In DFG and FTL, we watch the watchpoint and jettison once it is fired.
                 break;
             case GlobalPropertyLookUpStatus::NotFound:
                 break;
             }

             bool hasProperty = globalLexicalEnvironment->hasProperty(globalObject, entry.key.get());
             RETURN_IF_EXCEPTION(throwScope, nullptr);
             if (hasProperty) {
                 if (UNLIKELY(entry.value.isConst() && !vm.globalConstRedeclarationShouldThrow() && !isInStrictContext())) {
                     // We only allow "const" duplicate declarations under this setting.
                     // For example, we don't "let" variables to be overridden by "const" variables.
                     if (globalLexicalEnvironment->isConstVariable(entry.key.get()))
                         continue;
                 }
                 return createSyntaxError(globalObject, makeString("Can't create duplicate variable: '", String(entry.key.get()), "'"));
             }
         }

         // Check if any new "var"s will shadow any previous "let"/"const"/"class" names.
         // It's an error to introduce a shadow.
         if (!globalLexicalEnvironment->isEmpty()) {
             for (auto& entry : variableDeclarations) {
                 bool hasProperty = globalLexicalEnvironment->hasProperty(globalObject, entry.key.get());
                 RETURN_IF_EXCEPTION(throwScope, nullptr);
                 if (hasProperty)
                     return createSyntaxError(globalObject, makeString("Can't create duplicate variable: '", String(entry.key.get()), "'"));
             }
         }
     }


     m_unlinkedProgramCodeBlock.set(vm, this, unlinkedCodeBlock);

     BatchedTransitionOptimizer optimizer(vm, globalObject);

     for (size_t i = 0, numberOfFunctions = unlinkedCodeBlock->numberOfFunctionDecls(); i < numberOfFunctions; ++i) {
         UnlinkedFunctionExecutable* unlinkedFunctionExecutable = unlinkedCodeBlock->functionDecl(i);
         ASSERT(!unlinkedFunctionExecutable->name().isEmpty());
         globalObject->addFunction(globalObject, unlinkedFunctionExecutable->name());
         if (vm.typeProfiler() || vm.controlFlowProfiler()) {
             vm.functionHasExecutedCache()->insertUnexecutedRange(sourceID(),
                 unlinkedFunctionExecutable->typeProfilingStartOffset(),
                 unlinkedFunctionExecutable->typeProfilingEndOffset());
         }
     }

     for (auto& entry : variableDeclarations) {
         ASSERT(entry.value.isVar());
         globalObject->addVar(globalObject, Identifier::fromUid(vm, entry.key.get()));
         throwScope.assertNoException();
     }

     {
         JSGlobalLexicalEnvironment* globalLexicalEnvironment = jsCast<JSGlobalLexicalEnvironment*>(globalObject->globalScope());
         SymbolTable* symbolTable = globalLexicalEnvironment->symbolTable();
         ConcurrentJSLocker locker(symbolTable->m_lock);
         for (auto& entry : lexicalDeclarations) {
             if (UNLIKELY(entry.value.isConst() && !vm.globalConstRedeclarationShouldThrow() && !isInStrictContext())) {
                 if (symbolTable->contains(locker, entry.key.get()))
                     continue;
             }
             ScopeOffset offset = symbolTable->takeNextScopeOffset(locker);
             SymbolTableEntry newEntry(VarOffset(offset), static_cast<unsigned>(entry.value.isConst() ? PropertyAttribute::ReadOnly : PropertyAttribute::None));
             newEntry.prepareToWatch();
             symbolTable->add(locker, entry.key.get(), newEntry);

             ScopeOffset offsetForAssert = globalLexicalEnvironment->addVariables(1, jsTDZValue());
             RELEASE_ASSERT(offsetForAssert == offset);
         }
     }
     if (lexicalDeclarations.size()) {
 #if ENABLE(DFG_JIT)
         for (auto& entry : lexicalDeclarations) {
             // If WatchpointSet exists, just fire it. Since DFG WatchpointSet addition is also done on the main thread, we can sync them.
             // So that we do not create WatchpointSet here. DFG will create if necessary on the main thread.
             // And it will only create not-invalidated watchpoint set if the global lexical environment binding doesn't exist, which is why this code works.
             if (auto* watchpointSet = globalObject->getReferencedPropertyWatchpointSet(entry.key.get()))
                 watchpointSet->fireAll(vm, "Lexical binding shadows an existing global property");
         }
 #endif
         globalObject->bumpGlobalLexicalBindingEpoch(vm);
     }
     return nullptr;
 }

 auto ProgramExecutable::ensureTemplateObjectMap(VM&) -> TemplateObjectMap&
 {
     return ensureTemplateObjectMapImpl(m_templateObjectMap);
 }

 void ProgramExecutable::visitChildren(JSCell* cell, SlotVisitor& visitor)
 {
     ProgramExecutable* thisObject = jsCast<ProgramExecutable*>(cell);
     ASSERT_GC_OBJECT_INHERITS(thisObject, info());
     Base::visitChildren(thisObject, visitor);
     visitor.append(thisObject->m_unlinkedProgramCodeBlock);
     visitor.append(thisObject->m_programCodeBlock);
     if (TemplateObjectMap* map = thisObject->m_templateObjectMap.get()) {
         auto locker = holdLock(thisObject->cellLock());
         for (auto& entry : *map)
             visitor.append(entry.value);
     }
 }

 } // namespace JSC
	/*
	* Copyright (C) 2009-2019 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 "BatchedTransitionOptimizer.h"
	#include "CodeCache.h"
	#include "Debugger.h"

	namespace JSC {

	const ClassInfo ProgramExecutable::s_info = { "ProgramExecutable", &Base::s_info, nullptr, nullptr, CREATE_METHOD_TABLE(ProgramExecutable) };

	ProgramExecutable::ProgramExecutable(JSGlobalObject* globalObject, const SourceCode& source)
	: Base(globalObject->vm().programExecutableStructure.get(), globalObject->vm(), source, false, DerivedContextType::None, false, false, EvalContextType::None, NoIntrinsic)
	{
	ASSERT(source.provider()->sourceType() == SourceProviderSourceType::Program);
	VM& vm = globalObject->vm();
	if (vm.typeProfiler() \|\| vm.controlFlowProfiler())
	vm.functionHasExecutedCache()->insertUnexecutedRange(sourceID(), typeProfilingStartOffset(vm), typeProfilingEndOffset(vm));
	}

	void ProgramExecutable::destroy(JSCell* cell)
	{
	static_cast<ProgramExecutable*>(cell)->ProgramExecutable::~ProgramExecutable();
	}

	// http://www.ecma-international.org/ecma-262/6.0/index.html#sec-hasrestrictedglobalproperty
	enum class GlobalPropertyLookUpStatus {
	NotFound,
	Configurable,
	NonConfigurable,
	};
	static GlobalPropertyLookUpStatus hasRestrictedGlobalProperty(JSGlobalObject* globalObject, PropertyName propertyName)
	{
	PropertyDescriptor descriptor;
	if (!globalObject->getOwnPropertyDescriptor(globalObject, propertyName, descriptor))
	return GlobalPropertyLookUpStatus::NotFound;
	if (descriptor.configurable())
	return GlobalPropertyLookUpStatus::Configurable;
	return GlobalPropertyLookUpStatus::NonConfigurable;
	}

	JSObject* ProgramExecutable::initializeGlobalProperties(VM& vm, JSGlobalObject* globalObject, JSScope* scope)
	{
	auto throwScope = DECLARE_THROW_SCOPE(vm);
	RELEASE_ASSERT(scope);
	ASSERT(globalObject == scope->globalObject(vm));
	RELEASE_ASSERT(globalObject);
	ASSERT(&globalObject->vm() == &vm);

	ParserError error;
	JSParserStrictMode strictMode = isInStrictContext() ? JSParserStrictMode::Strict : JSParserStrictMode::NotStrict;
	OptionSet<CodeGenerationMode> codeGenerationMode = globalObject->defaultCodeGenerationMode();
	UnlinkedProgramCodeBlock* unlinkedCodeBlock = vm.codeCache()->getUnlinkedProgramCodeBlock(
	vm, this, source(), strictMode, codeGenerationMode, error);

	if (globalObject->hasDebugger())
	globalObject->debugger()->sourceParsed(globalObject, source().provider(), error.line(), error.message());

	if (error.isValid())
	return error.toErrorObject(globalObject, source());

	JSValue nextPrototype = globalObject->getPrototypeDirect(vm);
	while (nextPrototype && nextPrototype.isObject()) {
	if (UNLIKELY(asObject(nextPrototype)->type() == ProxyObjectType))
	return createTypeError(globalObject, "Proxy is not allowed in the global prototype chain."_s);
	nextPrototype = asObject(nextPrototype)->getPrototypeDirect(vm);
	}

	JSGlobalLexicalEnvironment* globalLexicalEnvironment = globalObject->globalLexicalEnvironment();
	const VariableEnvironment& variableDeclarations = unlinkedCodeBlock->variableDeclarations();
	const VariableEnvironment& lexicalDeclarations = unlinkedCodeBlock->lexicalDeclarations();
	// The ES6 spec says that no vars/global properties/let/const can be duplicated in the global scope.
	// This carried out section 15.1.8 of the ES6 spec: http://www.ecma-international.org/ecma-262/6.0/index.html#sec-globaldeclarationinstantiation
	{
	// Check for intersection of "var" and "let"/"const"/"class"
	for (auto& entry : lexicalDeclarations) {
	if (variableDeclarations.contains(entry.key))
	return createSyntaxError(globalObject, makeString("Can't create duplicate variable: '", String(entry.key.get()), "'"));
	}

	// Check if any new "let"/"const"/"class" will shadow any pre-existing global property names (with configurable = false), or "var"/"let"/"const" variables.
	// It's an error to introduce a shadow.
	for (auto& entry : lexicalDeclarations) {
	// The ES6 spec says that RestrictedGlobalProperty can't be shadowed.
	GlobalPropertyLookUpStatus status = hasRestrictedGlobalProperty(globalObject, entry.key.get());
	RETURN_IF_EXCEPTION(throwScope, nullptr);
	switch (status) {
	case GlobalPropertyLookUpStatus::NonConfigurable:
	return createSyntaxError(globalObject, makeString("Can't create duplicate variable that shadows a global property: '", String(entry.key.get()), "'"));
	case GlobalPropertyLookUpStatus::Configurable:
	// Lexical bindings can shadow global properties if the given property's attribute is configurable.
	// https://tc39.github.io/ecma262/#sec-globaldeclarationinstantiation step 5-c, `hasRestrictedGlobal` becomes false
	// However we may emit GlobalProperty look up in bytecodes already and it may cache the value for the global scope.
	// To make it invalid,
	// 1. In LLInt and Baseline, we bump the global lexical binding epoch and it works.
	// 3. In DFG and FTL, we watch the watchpoint and jettison once it is fired.
	break;
	case GlobalPropertyLookUpStatus::NotFound:
	break;
	}

	bool hasProperty = globalLexicalEnvironment->hasProperty(globalObject, entry.key.get());
	RETURN_IF_EXCEPTION(throwScope, nullptr);
	if (hasProperty) {
	if (UNLIKELY(entry.value.isConst() && !vm.globalConstRedeclarationShouldThrow() && !isInStrictContext())) {
	// We only allow "const" duplicate declarations under this setting.
	// For example, we don't "let" variables to be overridden by "const" variables.
	if (globalLexicalEnvironment->isConstVariable(entry.key.get()))
	continue;
	}
	return createSyntaxError(globalObject, makeString("Can't create duplicate variable: '", String(entry.key.get()), "'"));
	}
	}

	// Check if any new "var"s will shadow any previous "let"/"const"/"class" names.
	// It's an error to introduce a shadow.
	if (!globalLexicalEnvironment->isEmpty()) {
	for (auto& entry : variableDeclarations) {
	bool hasProperty = globalLexicalEnvironment->hasProperty(globalObject, entry.key.get());
	RETURN_IF_EXCEPTION(throwScope, nullptr);
	if (hasProperty)
	return createSyntaxError(globalObject, makeString("Can't create duplicate variable: '", String(entry.key.get()), "'"));
	}
	}
	}


	m_unlinkedProgramCodeBlock.set(vm, this, unlinkedCodeBlock);

	BatchedTransitionOptimizer optimizer(vm, globalObject);

	for (size_t i = 0, numberOfFunctions = unlinkedCodeBlock->numberOfFunctionDecls(); i < numberOfFunctions; ++i) {
	UnlinkedFunctionExecutable* unlinkedFunctionExecutable = unlinkedCodeBlock->functionDecl(i);
	ASSERT(!unlinkedFunctionExecutable->name().isEmpty());
	globalObject->addFunction(globalObject, unlinkedFunctionExecutable->name());
	if (vm.typeProfiler() \|\| vm.controlFlowProfiler()) {
	vm.functionHasExecutedCache()->insertUnexecutedRange(sourceID(),
	unlinkedFunctionExecutable->typeProfilingStartOffset(),
	unlinkedFunctionExecutable->typeProfilingEndOffset());
	}
	}

	for (auto& entry : variableDeclarations) {
	ASSERT(entry.value.isVar());
	globalObject->addVar(globalObject, Identifier::fromUid(vm, entry.key.get()));
	throwScope.assertNoException();
	}

	{
	JSGlobalLexicalEnvironment* globalLexicalEnvironment = jsCast<JSGlobalLexicalEnvironment*>(globalObject->globalScope());
	SymbolTable* symbolTable = globalLexicalEnvironment->symbolTable();
	ConcurrentJSLocker locker(symbolTable->m_lock);
	for (auto& entry : lexicalDeclarations) {
	if (UNLIKELY(entry.value.isConst() && !vm.globalConstRedeclarationShouldThrow() && !isInStrictContext())) {
	if (symbolTable->contains(locker, entry.key.get()))
	continue;
	}
	ScopeOffset offset = symbolTable->takeNextScopeOffset(locker);
	SymbolTableEntry newEntry(VarOffset(offset), static_cast<unsigned>(entry.value.isConst() ? PropertyAttribute::ReadOnly : PropertyAttribute::None));
	newEntry.prepareToWatch();
	symbolTable->add(locker, entry.key.get(), newEntry);

	ScopeOffset offsetForAssert = globalLexicalEnvironment->addVariables(1, jsTDZValue());
	RELEASE_ASSERT(offsetForAssert == offset);
	}
	}
	if (lexicalDeclarations.size()) {
	#if ENABLE(DFG_JIT)
	for (auto& entry : lexicalDeclarations) {
	// If WatchpointSet exists, just fire it. Since DFG WatchpointSet addition is also done on the main thread, we can sync them.
	// So that we do not create WatchpointSet here. DFG will create if necessary on the main thread.
	// And it will only create not-invalidated watchpoint set if the global lexical environment binding doesn't exist, which is why this code works.
	if (auto* watchpointSet = globalObject->getReferencedPropertyWatchpointSet(entry.key.get()))
	watchpointSet->fireAll(vm, "Lexical binding shadows an existing global property");
	}
	#endif
	globalObject->bumpGlobalLexicalBindingEpoch(vm);
	}
	return nullptr;
	}

	auto ProgramExecutable::ensureTemplateObjectMap(VM&) -> TemplateObjectMap&
	{
	return ensureTemplateObjectMapImpl(m_templateObjectMap);
	}

	void ProgramExecutable::visitChildren(JSCell* cell, SlotVisitor& visitor)
	{
	ProgramExecutable* thisObject = jsCast<ProgramExecutable*>(cell);
	ASSERT_GC_OBJECT_INHERITS(thisObject, info());
	Base::visitChildren(thisObject, visitor);
	visitor.append(thisObject->m_unlinkedProgramCodeBlock);
	visitor.append(thisObject->m_programCodeBlock);
	if (TemplateObjectMap* map = thisObject->m_templateObjectMap.get()) {
	auto locker = holdLock(thisObject->cellLock());
	for (auto& entry : *map)
	visitor.append(entry.value);
	}
	}

	} // namespace JSC