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Re: EGCS-1.0.2 pre fails on Spec CPU 95
>>>>> "Bill" == Bill Broadley <email@example.com> 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
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.