> many of the existing scripts make use of C bindings or rely on odd behaviors that aren't replicated by alternate VMs HHVM is compatible with PHP 5.3, LuaJIT

> many of the existing scripts make use of C bindings or rely on odd behaviors that aren't replicated by alternate VMs HHVM is compatible with PHP 5.3, LuaJIT with Lua 5.1 and PyPy with Python 2.7.3. All benchmark code is written the languages code and sometimes relies on an language extension library (which is written in C or C++). But three above JIT VMs come with their own compatible language extension libraries or support the extension API. Look at the code, it should be easy: http://benchmarksgame.alioth.debian.org/u32q/benchmark.php?test=pidigits&lang=php&id=1&data=u32q http://benchmarksgame.alioth.debian.org/u32q/benchmark.php?t... and https://github.com/kragen/shootout/tree/master/bench https://github.com/kragen/shootout/tree/master/bench