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Re: Libffi (git master) and guile (git master) on MIPS n32


On Mon, Feb 7, 2011 at 1:41 PM,  <rixed@happyleptic.org> wrote:
> The problem is : of these 64 bits, only the 32 lowest bits were set by
> guile, and the upper 32 are desperately random.

How were those lower 32bits set?  If set by the 32bit instructions
then it is automatically sign extended.  If not then there is a bug in
how guile is doing the returns
Unless you have a bug somewhere in which you are using a non sign
extended value with the 32bit instructions which then it becomes
undefined at what the value of those instructions do (could be either
treating it as a 64bit value, or do a sign extend or even put
0xDEADBEEFDEADBEEF in the register which is what the Octeon simulators
do).

-- Pinski


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