MuscalietJS: An Extensible Portable Layered JavaScript Engine

MuscalietJS is a layered architecture that splits responsibilities across two levels: a JavaScript-specific engine and a language-agnostic low-level VM. In principle, any managed language VM can serve as the low-level engine. Our current implementation uses the Common Language Runtime (CLR), as implemented by Mono. The low-level VM provides traditional compiler optimizations: instruction scheduling, register allocation, constant propagation, common sub expression elimination, etc., as well as code generation and machine specific optimizations. In addition it provides managed language services such as garbage collection, allowing us to focus on the JavaScript-specific aspects of the engine. Running the JavaScript engine inside another VM has performance implications. Our split design relies on JavaScript specific optimizations at the high-level to help mitigate the overhead of running on the CLR. The JavaScript engine code generator exploits advanced high-level techniques combined with type analysis and special hints to lead the low-level engine to generate high-quality optimized code. There are performance advantages to running on top of the CLR.

=========== System Requirement:

-- If using Mono, make sure to install Mono v3.0 or higher first and make sure mono executable is in your PATH

-- If using Visual Studio, make sure it supports .NET 4.5 (VS12 for instance).

=========== Building MCJS:

After cloning the git repo for MCJS, change directory to the root folder of the repo. Then run the following:

git submodule update --init --recursive

For the rest of the commands here we assume you are in the root directory.

-- Linux Builds:

You must have mono version 3.0 or higher already installed and in your PATH. You can use xbuild or make to build. The following command builds ./MCJavascript/bin/Release/MCJavascript.exe:

make

or

make JS_BUILD_TYPE=Release

The following command builds ./MCJavascript/bin/Debug/MCJavascript.exe:

make JS_BUILD_TYPE=Debug

-- Windows Builds:

You can use Visual Studio or Xamarin Studio to open and build MCJavascript. In the root MCJavascript directory open MCJavascript-VS.sln solution and build.

NOTE: If building for the first time, please first build in RELEASE mode once and then you can build in DEBUG mode.

=========== Contributing and using MuscalietJS:

-- Please cite the MuscalietJS original paper if you are using this tool in your research:

"MuscalietJS: Rethinking Layered Dynamic Web Runtimes" Behnam Robatmili, Calin Cascaval, Mehrdad Reshadi, Madhukar N. Kedlaya, Seth Fowler, Michael Weber, Ben Hardekopf, Virtual Execution Environments (VEE), March 2014

-- If you want to contribute to MuscalietJS, please refer to MuscalietJS Contribution Agreement provided in the repository.

For more documentation, please refer to docs/MCJS.pdf in the repo