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32-bit multiplication



Hi all,

 

Have a question about 32-bit multiplication on SPARC:

Does RTEMS allow 32-bit multiplication, I mean, does it give a 64-bit result
or just the lower 32-bit?

 

Think that this is part of the umul function which is on the GCC, and in
part of the code it has something like:

 

! the upper 32 bits of product are wrong, but we do not care

 

I also performed some tests and the value was not correctly presented.

 

Is there a particular reason why the upper 32 bits are not correctly
calculated? Are other 64-bit operations allowed (such as sum, division,
etc)?

 

Thank you very much

 

Kind regards

Manuel Coutinho

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