> The issue is most probably that on GIMPLE we only deal with ptr_mode, > not Pmode, and IVOPTs thinks that pointer induction variables will > have ptr_mode. To fix this the cost computation would need to take > into account ptr_mode to Pmode conversions _and_ would need to > consider Pmode IVs in the first place (I'm not sure that will be easy).
Thank you Richard for you reply. I guess such an issue is not in the top priority tasks of main developers. So I think I'll have to look at it myself if I feel confident enough to carry out such a job (I've never worked at tree level). My main wonder is about Pmode IVs: since GIMPLE representation only deals with ptr_mode, what differentiates a Pmode IV from a ptr_mode one? BTW, this wonder is not limited to IVs. What does control the choice of Pmode vs ptr_mode when mapping to RTL? Thanks, Aurélien
