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Diffstat (limited to 'Userland/Libraries/LibJS/Runtime/VM.h')
| -rw-r--r-- | Userland/Libraries/LibJS/Runtime/VM.h | 290 |
1 files changed, 290 insertions, 0 deletions
diff --git a/Userland/Libraries/LibJS/Runtime/VM.h b/Userland/Libraries/LibJS/Runtime/VM.h new file mode 100644 index 0000000000..320ea53405 --- /dev/null +++ b/Userland/Libraries/LibJS/Runtime/VM.h @@ -0,0 +1,290 @@ +/* + * Copyright (c) 2020, Andreas Kling <kling@serenityos.org> + * 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 THE COPYRIGHT HOLDERS AND 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 THE COPYRIGHT HOLDER 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. + */ + +#pragma once + +#include <AK/FlyString.h> +#include <AK/HashMap.h> +#include <AK/RefCounted.h> +#include <AK/StackInfo.h> +#include <LibJS/Heap/Heap.h> +#include <LibJS/Runtime/CommonPropertyNames.h> +#include <LibJS/Runtime/Error.h> +#include <LibJS/Runtime/ErrorTypes.h> +#include <LibJS/Runtime/Exception.h> +#include <LibJS/Runtime/MarkedValueList.h> +#include <LibJS/Runtime/Value.h> + +namespace JS { + +enum class ScopeType { + None, + Function, + Block, + Try, + Breakable, + Continuable, +}; + +struct ScopeFrame { + ScopeType type; + NonnullRefPtr<ScopeNode> scope_node; + bool pushed_environment { false }; +}; + +struct CallFrame { + FlyString function_name; + Value this_value; + Vector<Value> arguments; + Array* arguments_object { nullptr }; + ScopeObject* scope { nullptr }; + bool is_strict_mode { false }; +}; + +class VM : public RefCounted<VM> { +public: + static NonnullRefPtr<VM> create(); + ~VM(); + + bool should_log_exceptions() const { return m_should_log_exceptions; } + void set_should_log_exceptions(bool b) { m_should_log_exceptions = b; } + + Heap& heap() { return m_heap; } + const Heap& heap() const { return m_heap; } + + Interpreter& interpreter(); + Interpreter* interpreter_if_exists(); + + void push_interpreter(Interpreter&); + void pop_interpreter(Interpreter&); + + Exception* exception() + { + return m_exception; + } + + void clear_exception() { m_exception = nullptr; } + + class InterpreterExecutionScope { + public: + InterpreterExecutionScope(Interpreter&); + ~InterpreterExecutionScope(); + + private: + Interpreter& m_interpreter; + }; + + void gather_roots(HashTable<Cell*>&); + +#define __JS_ENUMERATE(SymbolName, snake_name) \ + Symbol* well_known_symbol_##snake_name() const { return m_well_known_symbol_##snake_name; } + JS_ENUMERATE_WELL_KNOWN_SYMBOLS +#undef __JS_ENUMERATE + + Symbol* get_global_symbol(const String& description); + + PrimitiveString& empty_string() { return *m_empty_string; } + PrimitiveString& single_ascii_character_string(u8 character) + { + ASSERT(character < 0x80); + return *m_single_ascii_character_strings[character]; + } + + void push_call_frame(CallFrame& call_frame, GlobalObject& global_object) + { + ASSERT(!exception()); + // Ensure we got some stack space left, so the next function call doesn't kill us. + // This value is merely a guess and might need tweaking at a later point. + if (m_stack_info.size_free() < 16 * KiB) + throw_exception<Error>(global_object, "RuntimeError", "Call stack size limit exceeded"); + else + m_call_stack.append(&call_frame); + } + + void pop_call_frame() { m_call_stack.take_last(); } + + void push_ast_node(const ASTNode& node) { m_ast_nodes.append(&node); } + void pop_ast_node() { m_ast_nodes.take_last(); } + + CallFrame& call_frame() { return *m_call_stack.last(); } + const CallFrame& call_frame() const { return *m_call_stack.last(); } + const Vector<CallFrame*>& call_stack() const { return m_call_stack; } + Vector<CallFrame*>& call_stack() { return m_call_stack; } + const Vector<const ASTNode*>& node_stack() const { return m_ast_nodes; } + + const ScopeObject* current_scope() const { return call_frame().scope; } + ScopeObject* current_scope() { return call_frame().scope; } + + bool in_strict_mode() const; + + template<typename Callback> + void for_each_argument(Callback callback) + { + if (m_call_stack.is_empty()) + return; + for (auto& value : call_frame().arguments) + callback(value); + } + + size_t argument_count() const + { + if (m_call_stack.is_empty()) + return 0; + return call_frame().arguments.size(); + } + + Value argument(size_t index) const + { + if (m_call_stack.is_empty()) + return {}; + auto& arguments = call_frame().arguments; + return index < arguments.size() ? arguments[index] : js_undefined(); + } + + Value this_value(Object& global_object) const + { + if (m_call_stack.is_empty()) + return &global_object; + return call_frame().this_value; + } + + Value last_value() const { return m_last_value; } + void set_last_value(Badge<Interpreter>, Value value) { m_last_value = value; } + + const StackInfo& stack_info() const { return m_stack_info; }; + + bool underscore_is_last_value() const { return m_underscore_is_last_value; } + void set_underscore_is_last_value(bool b) { m_underscore_is_last_value = b; } + + void unwind(ScopeType type, FlyString label = {}) + { + m_unwind_until = type; + m_unwind_until_label = label; + } + void stop_unwind() { m_unwind_until = ScopeType::None; } + bool should_unwind_until(ScopeType type, FlyString label = {}) const + { + if (m_unwind_until_label.is_null()) + return m_unwind_until == type; + return m_unwind_until == type && m_unwind_until_label == label; + } + bool should_unwind() const { return m_unwind_until != ScopeType::None; } + + ScopeType unwind_until() const { return m_unwind_until; } + + Value get_variable(const FlyString& name, GlobalObject&); + void set_variable(const FlyString& name, Value, GlobalObject&, bool first_assignment = false); + + Reference get_reference(const FlyString& name); + + template<typename T, typename... Args> + void throw_exception(GlobalObject& global_object, Args&&... args) + { + return throw_exception(global_object, T::create(global_object, forward<Args>(args)...)); + } + + void throw_exception(Exception*); + void throw_exception(GlobalObject& global_object, Value value) + { + return throw_exception(heap().allocate<Exception>(global_object, value)); + } + + template<typename T, typename... Args> + void throw_exception(GlobalObject& global_object, ErrorType type, Args&&... args) + { + return throw_exception(global_object, T::create(global_object, String::formatted(type.message(), forward<Args>(args)...))); + } + + Value construct(Function&, Function& new_target, Optional<MarkedValueList> arguments, GlobalObject&); + + String join_arguments() const; + + Value resolve_this_binding(GlobalObject&) const; + const ScopeObject* find_this_scope() const; + Value get_new_target() const; + + template<typename... Args> + [[nodiscard]] ALWAYS_INLINE Value call(Function& function, Value this_value, Args... args) + { + if constexpr (sizeof...(Args) > 0) { + MarkedValueList arglist { heap() }; + (..., arglist.append(move(args))); + return call(function, this_value, move(arglist)); + } + + return call(function, this_value); + } + + CommonPropertyNames names; + + Shape& scope_object_shape() { return *m_scope_object_shape; } + +private: + VM(); + + [[nodiscard]] Value call_internal(Function&, Value this_value, Optional<MarkedValueList> arguments); + + Exception* m_exception { nullptr }; + + Heap m_heap; + Vector<Interpreter*> m_interpreters; + + Vector<CallFrame*> m_call_stack; + Vector<const ASTNode*> m_ast_nodes; + + Value m_last_value; + ScopeType m_unwind_until { ScopeType::None }; + FlyString m_unwind_until_label; + + StackInfo m_stack_info; + + bool m_underscore_is_last_value { false }; + + HashMap<String, Symbol*> m_global_symbol_map; + + PrimitiveString* m_empty_string { nullptr }; + PrimitiveString* m_single_ascii_character_strings[128] {}; + +#define __JS_ENUMERATE(SymbolName, snake_name) \ + Symbol* m_well_known_symbol_##snake_name { nullptr }; + JS_ENUMERATE_WELL_KNOWN_SYMBOLS +#undef __JS_ENUMERATE + + Shape* m_scope_object_shape { nullptr }; + + bool m_should_log_exceptions { false }; +}; + +template<> +[[nodiscard]] ALWAYS_INLINE Value VM::call(Function& function, Value this_value, MarkedValueList arguments) { return call_internal(function, this_value, move(arguments)); } + +template<> +[[nodiscard]] ALWAYS_INLINE Value VM::call(Function& function, Value this_value, Optional<MarkedValueList> arguments) { return call_internal(function, this_value, move(arguments)); } + +template<> +[[nodiscard]] ALWAYS_INLINE Value VM::call(Function& function, Value this_value) { return call(function, this_value, Optional<MarkedValueList> {}); } + +} |