[LLVMdev] i128 backend or frontend lowering

[Dan Gohman]

On Aug 6, 2009, at 12:34 PM, Anton Korobeynikov wrote:


> Hello, Andrew
>
>
>> Is the backend the best place to do this or should I attempt to make
>>
>> llvm-gcc not generate i128 in the first place?
>>
> It depends whether i128 is a native type for alpha, or not. If it's
> not - frontend should not generate it.

No, CodeGen will legalize types like i128 by expanding them into
multiple registers, and this includes the calling-convention code
(both new and old). The arguments and return values are communicated
between target independent code and target dependent code in
register-sized pieces. I'll add some comments to describe this better.

Dan