RE: CPU specific binaries

[arto.astala@nokia.com]

All this comes out of thin air, but here goes:

*  I think that currently the goal is to support the highest
   optimization that does not hurt (noticeably) the low end
   machines. I think this includes Pentium optimizations,
   but naturally none of the instruction set extensions.
   Optimization for PII or higher is probably not ok.

*  Any optimization should not introduce compile time errors.
   Some may result in execution errors. Most of these are
   illegal instructions. Some may be legal sequences of
   instructions that just give a different result. Intel
   has tried hard to avoid these, however, so it may be that
   there are no such things.

*  There should be a set of optimizations that is always safe
   to apply in any x86 architecture machine. The larger we
   get this set and the better we ensure that all Debian
   packages use it the better our base line is.

*  The next thing would be to define a standard way to enable
   some set of processor model specific optimizations. This
   is really also a prerequisite for parallel binary model-
   optimized distributions. It has to use auotobuild to work.

t.aa