[llvm-dev] New intrinsic property IntrOnlyWrite

[Nicolai Hähnle via llvm-dev]

On 19.03.2016 16:25, Mehdi Amini wrote:
> Hi,
>
> Can you elaborate what is the impact at the IR level?
> If the point is just about how you lower for you target, why are you needing an IR level attribute? You backend if free to specialize the lowering for any intrinsic regardless the IR level attributes.

As I explained in my reply to Philip, what I really need is a way to get 
TableGen to shut up about what it reasonably believes to be a mismatch 
between the properties of the intrinsic (which it conservatively 
believes to be mayLoad = 1, mayStore = 1, hasSideEffects = 1) and the 
hardware instruction (which is correctly mayLoad = 0, mayStore = 1, 
hasSideEffects = 0).

Indeed, write-only without an ArgMemOnly property may well be useless at 
the IR level. If you think that there is a better way to explain the 
situation to TableGen, please let me know.

Please see my mail to Philip for a more detailed explanation for why we 
are in this situation.

Thanks,
Nicolai