[LLVMdev] GEPping GEPs and first-class structs

[Gordon Henriksen]

On Feb 1, 2009, at 08:38, Jon Harrop wrote:

> As I understand it, first-class structs will allow structs to be  
> passed as function arguments and returned as results (i.e. multiple  
> return values) instead of passing pointers to structs. However, the  
> GEP instruction only handles pointer types. So I do not understand  
> how you will be able to extract the fields of a struct when it is  
> received as a value type.
>
> Will the GEP instruction be altered so that it can be applied to  
> structs directly?


You can't take the address of a register, much less an element  
thereof. extractvalue and insertvalue are the instructions to  
manipulate aggregate registers.

http://llvm.org/docs/LangRef.html#aggregateops

— Gordon