Re: Green Hills 64 Bit Float Problem on PowerPC 603

[DPH <kgclg15@kg.hsanet.net>]

Martin Dowie wrote:

> Just guessing, but has it choosen 424 bytes as this is "mod 8 = 0" long,
> long word aligned?

Not sure.  I really gotta find out where it stuck those extra 4 bytes, tho,
and what logic it used when it placed them wherever it did.  If at the end of
the message, then fine - it won't hurt how the tool picks up data from the
file.  If it stuck it in somewhere in the middle, then the tool will be
finding wrong data after that... until I figure out how to predict the anomaly
and compensate for it.


> Isn't the simplest way to resolve this question just to insert a few known
> values do some
> maths and check the results?

Well, its a real time system.  Inserting anything isn't exactly the easiest
thing to do.  None of the code for it is mine - I'd have to get someone to
make a special build, maybe init a long float to a certain value and then
capture it.  It'd involve a special lab run at a lab that's a matter of a half
hour or so to bring on line, etc.  No, the easiest thing would be for someone
here with specific knowledge of how a Power PC chip on an MVME board treats
long floats to gimmie a clue about it! <G>

Dave Head


> DPH <kgclg15@kg.hsanet.net> wrote in message
> news:3AC264E3.742D050E@kg.hsanet.net...
> [snip]
> > Complicating the analysis is the fact that the message is 4 bytes longer
> > than it should be.  That is, representation specifications say it should
> > be 420 bytes long, but it is 424 bytes long.  No, I haven't been able to
> > figure out where the extra 4 bytes are located.