induct regression in gcc 4.3.1

[Tim Prince]

Jack Howarth wrote:
>    It appears that the performance regression which
> I found in the induct polyhedron benchmark in gcc 4.3.1 is
> triggered by the use of -ffast-math. Benchmarking induct
> compiled with gcc 4.2.4 and 4.3.1 shows....
> 
>                    gcc 4.2.4       gcc 4.3.1
>                     Ave Run         Ave Run 
> -O3                  73.57           71.71
> -ffast-math -O3      68.27           89.76
> 

This seems insufficiently informative.  Is it attempting to vectorize dot 
products of length 3, for example?