[LLVMdev] Loss of precision with very large branch weights

[Diego Novillo]

On 04/24/15 14:44, Xinliang David Li wrote:
>
> Isn't that the direct result of  the branch weights not being scaled
> (after reaching the cap) -- thus leading to wrong branch probability
> (computed from weights)? Wrong probability leads to wrong Frequency
> propagation.

Yup, I'm trying to see if we couldn't just use 64bit values all over to 
make things easier. The drawback would be that we are just punting the 
problem to a different scale of values (but, it may be enough).


Diego.