Compilers
The PHP language was originally implemented as an interpreter. Several compilers have been developed which decouple the PHP language from the interpreter. Advantages of compilation include better execution speed, static analysis, and improved interoperability with code written in other languages. PHP compilers of note include Phalanger, which compiles PHP into Common Intermediate Language (CIL) bytecode, and HipHop, developed at Facebook and now available as open source, which transforms the PHP Script into C++, then compiles it, reducing server load up to 50%.
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