Re: Very Fast: Directly Coded Lexical Analyzer

["J.C. Pizarro" <jcpiza at gmail dot com>]

2007/6/1, Frank Schaefer <frank_r_schaefer@gmx.net> wrote:
> > To obtain 200-250% in speed gain won't be possible for this GCC
> > optimizing compiler because of http://en.wikipedia.org/wiki/Amdahl%27s_law
>
> Amdahl's Law talks about paralellism. That is not the case here.
> He apply a different approach for lexical analysis as mentioned
> above. If you talk about the influence of a new lexer to the
> speed of the whole compiler, I would aggree that the a speed up
> factor 2 is not possible if lexical analysis constitutes less
> than 50% of the total computation effort (simple math).

Amdahl's Law talks about sequential improvement too.

http://en.wikipedia.org/wiki/Amdahl%27s_law#Speedup_in_a_sequential_program