Re: [Qemu-devel] [PATCH v6 2/5] Implement i.MX31 Clock Control Module

[Paolo Bonzini]

Il 23/04/2012 22:54, Peter Chubb ha scritto:
> Peter> What is this calculation supposed to do? It doesn't convert a
> Peter> 10-bit signed twos-complement number into an int32_t, unless
> Peter> I'm confused... Also, it's a rather opaque way to write "mfn &=
> Peter> 0x200;".
> 
> I'll use a different way to calculate.  Maybe:
>      mfn <<= (32-10);
>      mfn >>= (32-10);

The magic that you wanted is

   mfn |= -(mfn & 0x200);

:) but I do prefer the shifts too.

Paolo