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Re: EGCS-1.0.2 pre fails on Spec CPU 95

>>>>> "Bill" == Bill Broadley <> writes:

 Bill> Results are available on intel using the Intel reference
 Bill> compiler which gets very good numbers.

Presumably it's tuned to be fast and correct for this case :-).  I've
heard the Fortran compiler compared unfavourably to g77 elswhere...

 Bill> egcs-1.0.1/g77  failed on -O2, but works with -O1.

 Bill> egcs-1.0.2 worked with -O2 but did NOT work with -m486
 Bill> -fomit-frame-pointer -O2 It finished all the benchmarks but one
 Bill> then failed and produced the wrong output.

This sounds suspiciously like a numerical problem with the code.  Is
it cured (with the expected slowdown) by -ffloat-store or other
options from the `Working Code' (?) node of the g77 manual?  A
surprisingly large number of Fortran benchmarks have programming
problems of one sort or another which g77 exposes, although it's often
difficult to persuade people of this.

 Bill> Unfortunately I can't give out the source, 

What is the program at issue?  Perhaps we can find source elsewhere
(if, as I understand, Spec is compiled from original freely-available
sources).  Alternatively I can suggest sources of tools with which to
check it.

Regarding speed, the usual x86 problems with alignment of doubles
(when are we going to get that fixed??), -funroll-loops and
-fforce-addr at least may be relevant, but I don't know anything about
what's in spec95.

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