OK. Here's the deal. Way back when, compiler specialists implemented
    an idea called bootstrapping. What's bootstrapping? You break a compiler
    into 5 different section. The later sections are machine dependant, but
    the first sections can be re-used for any machine on any platform. How
    can it be re-used? (next section)
    Highlevel instructions are automatically translated into a tripplet or
    a quadrouplet (i'll call them trips or quads from here on). A trip or
    a quad is a machine independent pseudo assembly language.
    eg:
         a = b + c * e;
         * c e t1
         + b t1 t2
         = t2 0 a
         This is a quad example. The first column is the operation to
         perform. The second and third are the operands and the fourth
         column is where to store the result of the operation. 
         Note : t1 t2 ... refer to temporary variable. These could represent
         actual memory locations or registers down the line
    The quads generated say the following: 
         multiply 'c' and 'e' and store the result in 't1'
         add 'b' and 't1' and store the result in 't2'
         copy 't2' and store it into 'a' (0 is an empty operand)
    These quads are not optimized yet. Durring compilation, the computer
    has no way of knowing whats coming next so it store results in temps
    and uses alot of them.
    Here's where machine independant optimization comes into play.
         * c e t1
         + b t1 t2
         = t2 0 a
         These quads can be optimized simply by storing the last
         addition result in a
         * c e t1
         + b t1 a
         These have the same effect. However, this basic block can be
         reduced to variables only by noting that 'a' never is used in
         the formula and 'a' can be used as a temp variable
         * c e a
         + b a a
    This is an example of machine independant optimization, and guess what?
    Most compilers are made using the bootstrapping method so If I wrote
    a pascal compiler and c++ compiler I could re-use the optimizer and 
    code generator for both.
    Parts of a compiler
    scanner -> parser -> intermediate code generator -> optimizer -> code
    generatro
    The optimization spoken of lately resides in the code generator for
    machine specific optimization.
--- GEcho 1.00
---------------