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(librep.info)Compiled Lisp

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Compiled Lisp
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   `librep' contains a Lisp compiler as well as an interpreter; this
takes a Lisp form or program and compiles it into a "byte-code" object.
This byte-code object is a string of characters representing virtual
machine instructions, a vector of constants and some other
meta-information. The system also contains a byte-code interpreter;
this takes the compiled byte-codes and executes them by simulating the
virtual machine. This simulation will have exactly the same effect as
interpreting the original form or program.

   One of the main reasons for compiling programs is to increase their
efficiency. Compiled functions are likely to be more efficient than
interpreted counterparts in all areas (space and time). For example:

     user> (define (fib n) (if (<= n 2) 1 (+ (fib (- n 1)) (fib (- n 2)))))
     user> ,time (fib 30)
     832040
     Elapsed: 17.05572 seconds
     user> ,compile
     user> ,time (fib 30)
     832040
     Elapsed: 1.479007 seconds

--the compiled function is over an order of magnitude faster than the
interpreted version.

Compilation Functions

How to compile Lisp programs

Compiler Declarations

Hinting to the compiler

Compilation Tips

Getting the most out of the compiler

Disassembly

Examining compiled functions