[Vm-dev] 64bit FFI?
bert at freudenbergs.de
Thu Feb 12 19:30:14 UTC 2009
On 12.02.2009, at 20:18, Eliot Miranda wrote:
> AFAICT you can produce a 64-bit VM that runs a 32-bit image with
> this technique, but you can't get a VM that runs both.
That's exactly as stated in the FAQ. Any given VM can run *either* 32-
bit images *or* 64-bit images. It's a compile-time choice.
> On the other hand, start-up code that reads a 32-bit image and
> swizzles it to a full 64-bit image is perfectly sensible and quite
> easy in the Squeak context because (IIRC) the 64-bit format doesn't
> do things like widen the SmallInteger range, implement immediate
> Floats, etc. Its simply a matter of reading the data, writing two
> words for each oop and scaling each non-SmallInteger oop
> appropriately. But as I said I don't see this code anywhere.
This is not the job of the VM. You have to manually create a 64 bit
- Bert -
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