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Re: floating point war casualty list


At 4:33 PM -0400 5/28/02, Paul Koning wrote:
>  >>>>> "Zack" == Zack Weinberg <zack@codesourcery.com> writes:
>  Zack> That leaves the i370 (IBM_FLOAT_FORMAT), pdp11
>  Zack> (VAX_FLOAT_FORMAT, or should be), and ns32k (no idea) as
>  Zack> potential problems.  Can people familiar with these targets say
>  Zack> what the situation is?
>
>pdp11 in the current tree does not specify float format, and indeed
>the results that produces are definitely wrong.  I set it to
>VAX_FLOAT_FORMAT and that produces the right answers -- at least it
>matches for 0.5 and 0.25 and 10.0 and the log10(2) that Stephen
>pointed to.
>
>      paul

If I recall correctly, there are TWO (or more) PDP-11 floating point 
formats.  I think it
had something to do with word-order for the double-precision FP, but 
since it's been
close to 25 years since I last did anything with the PDP-11 my memory 
is somewhat
fuzzy.

-- Al

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