
You appear to be on a Dec ALPHA without gcc installed.  Gcc does a better job
optimizing generated code than DEC's cc.  It appears that DEC's cc reserves
several registers (probably for use in software pipelining), and that prevents
ATLAS from achieving maximal performance.  

The second rather surprising result on ALPHAs is that EGCS and new versions
of gcc produces much less optimal code than gcc 2.8 or earlier.  You will
lose roughly 10% of performance by using newer gcc.  The errata file
   www.cs.utk.edu/~rwhaley/ATLAS/errata.html
contains pointers to instructions on downloading and compiling an old version
of gcc.

If you continue the ATLAS install without first installing gcc 2.8 or earlier,
your performance will be subpar, and ATLAS will have to search for the best
parameters.

