[Freeciv-Dev] Re: [Patch] Bool cleanup of options.c

[Tony Stuckey <stuckey@xxxxxxxxxxxxxxxxx>]

On Mon, Mar 18, 2002 at 08:48:53AM +0100, Raimar Falke wrote:
> On Sun, Mar 17, 2002 at 10:13:54PM -0500, Ross W. Wetmore wrote:
> > Is it even noticeable, or do the extra code instructions to handle
> > bytes swamp the data memory savings for anything but a bool[]?
> 
> What extra code instructions?

        These will certainly be present on Alpha architectures.  While I
don't know anything about ARM and some other chips, I don't think that
x86, M68K, or Sparc will have any issues at all.  (Other that Raimar's
noted occasional sign-extend at function return for ABI reasons)

> > Also, memory access is actually optimized for word or word multiples. If
> > random bytes cause other accesses to cross these boundaries, you lose in
> > a big way.
> 
> Quite possible.

        GCC should pad out to reasonable alignments, other compilers might
or might not.
-- 
Anthony J. Stuckey                              stuckey@xxxxxxxxxxxxxxxxx
"And they said work hard, and die suddenly, because it's fun."
        -Robyn Hitchcock.