Feedback optimization

[John D. McCalpin]

Thanks to:
     Len Lattanzi (len at Synthesis.com) Synthesis Software Solutions, Inc.
for information about the feedback optimization.

Some more questions:
    (1) Can both of these options (cache reorganization and inlining)
	be used at the same time?
    (2) The -O3 with the -feedback option worked.  I got no speedup
	on this particular code, but that is not necessarily a problem.
    (3) The -cord option does NOT work.  The compiler gets almost to
	the end before bombing --- it could not find /usr/bin/ftoc.
	What does ftoc do, and should it be there?

By the way, I am not running dhrystone :-).  I am running LINPACK and
a variety of floating-point intensive finite-difference PDE codes.

So far it looks like loop unrolling buys a lot on this machine.
On 32-bit LINPACK (order 100 case), with full optimization -O3,
unrolling the innermost loops (the BLAS subroutines) gives a speedup
from 1.4 to 1.9 MFLOPS (unrolled to a depth of 16).  I still can't 
recover the 3.0 MFLOPS in the LINPACK published results for the MIPS
M-800 (which should be the same CPU and clock speed).
--
----------------------  John D. McCalpin -------------------------
Mesoscale Air-Sea Interaction Group  &  Department of Oceanography
 & Supercomputer Computations Research Institute - Fl State Univ.
mccalpin at masig1.ocean.fsu.edu		mccalpin at nu.cs.fsu.edu
mccalpin at fsu	(BITNET or MFENET)	SCRI::MCCALPIN	(SPAN)
------------------------------------------------------------------