System V Application Binary Interface 0.99.5

[Andrew Haley]

[Resending, this time CC:'d to GCC list.]

I'm looking at Section 3.2.3, Parameter Passing.
http://artfiles.org/kernel.org/pub/scm/devel/binutils/hjl/x86-64-psabi.git/

I still cannot tell whether parameters should or should not be sign- or
zero-extended when they are moved into registers at a call.  I'm guessing
not.

Which is it?  This is important for interworking.

Thanks,
Andrew.