Read about the changes made to improve performance below,
- In Windows 10 and Microsoft Edge, we’ve started optimizing Chakra’s parser and the JIT compiler to identify non const variable declarations of integers that are defined globally and are never changed during the course of the execution time of the program. Once identified, the JIT’ed code produced by Chakra is able to substantially reduce the lookup cost associated with such globally defined variables that do not change their shape and value during the execution lifetime of the program, thus extending the performance oriented value proposition of the const statement in ECMAScript 6 to how constants are often used in the web as it exists today.
- Until Windows 10, Chakra did not optimize code inside of try-catch blocks. In Windows 10 and Microsoft Edge, Chakra’s compiler now has the capability to abstract out the code defined inside of the try-catch blocks and generate optimized JIT code for it. For cases where an exception is not thrown, Chakra now executes such code inside a try block almost on par with regular JIT’ed code (as if the try-catch never existed).
- The experiment confirmed that usage of minified code is extremely popular on the web as it exists and amongst others, UglifyJS is very commonly used in today’s web. So in Windows 10 and Microsoft Edge, we’ve added new fast paths, improved inlining and optimized some heuristics in Chakra’s JIT compiler to ensure that minified code runs as fast, if not faster than the non-minified versions. With these changes, the performance of individual code patterns minified using UglifyJS that we tested, improved between 20-50%
- Given the popularity of Array built-ins on the web, in Windows10 and Microsoft Edge, Chakra has optimized how values are retrieved, while the engine traverses a given array. This optimization helps remove the extraneous overhead of visiting the prototype chain and looking up the numeric property corresponding to the index, when holes are encountered in an array. This optimization helps improves the performance of ECMAScript5 Array#indexOf built-in in Chakra and Microsoft Edge by more than 5 times.
Read more about it here.