sentence: mono-specific enhancements native interop services and com interop security - code execution engine the mono runtime contains a code execution engine that translates ecma cil byte codes into native code and supports a number of processors : arm , mips ( in 32-bit mode only ) , sparc , powerpc , s390 ( in 64-bit mode ) , x86 , x86-64 and ia-64 for 64-bit modes .