Hello. I wrote new ECMA262 5.1 full support engine "iv / lv5" in C++. This is highly inspired from JSC, V8 and SpiderMonkey. (especially JSC)
https://github.com/Constellation/iv This aims at most precise engine to ECMA262 5.1 specification. (like the great engine,) I read ECMA262 and wanted precise engine to understand this spec, so I created. features, all ECMA262 5.1th features (strict mode, direct call / indirect call to eval, PropertyDescriptor, early errors, Object.prototype.toString.call(null / undefined), Object extras, Array extras, etc.) BESEN // for example, directive prologure including octal value and strict directive is rejected. function test() { "¥02"; "use strict"; } stack VM JSC like bytecode based PIC ES5 oriented structures in C++ (PropertyDescriptor, Attributes(Enumerable, Writable, Configurable)) optimized JSArray (using vector and hash map) but this array implements full features of ECMA262 5.1th. for example, var ary = [0, 1]; Object.defineProperty(ary, 'length', { writable : false }); ary.length = 4; // of cource, in strict mode, this raises error. print(ary.length); // 2 try { ary.push(2); // throw TypeError, because [DefineOwnProperty] with throw = true is called. } catch (e) { print(e); } ary[3] = 2; // of cource ... print(ary.length); // 2; minimum source code 2 engines, VM and AST Interpreter. we can switch it by command line option. bytecode based backtrack RegExp (read re1 report and source code to study VM based RegExp runtime, and implemented it) ES5 oriented optimization for example, if I get "eval" keyword in strict mode, don't make variable dynamic (hold on heap variable with offset access) because direct call to eval in strict mode cannot create new variable in upper local call site environment. At first, I created AST Interpreter (named "teleporter") which algorithm is just the same to ECMA262 specification. And after it is done, I created optimized bytecode VM (named "railgun"). These 2 engines are abstracted, so we can switch it at runtime. ('--interp option') AST Interpreter is very slow, but this source code is exactly the same to ECMA262 specification algorithm, so this may be interesting for spec readers. And, SunSpider is available for this engine, so, you can bench it. (sorry, probably slow, because of no JIT...) I'm planning to create own GC (now using BoehmGC library), and create JIT module. Finally, I'm respecting JSC, V8, SpiderMonkey, BESEN implementors great works. Thanks. _______________________________________________ es-discuss mailing list [email protected] https://mail.mozilla.org/listinfo/es-discuss
