On 03/06/2014 08:55 AM, Paulo Matos wrote: > Hi, > > Upon noticing ira-hoist-pressure in `gcc --help=optimizers` and not > ira-loop-pressure, > I am wondering why the latter is not marked as an Optimization in common.opt: > > fira-loop-pressure > Common Report Var(flag_ira_loop_pressure) > Use IRA based register pressure calculation > in RTL loop optimizations. > > Should we mark it as such? > > It is not an optimization strictly speaking. It is a better register pressure calculation used for invariant loop motion decisions.
On the other hand, using this option can improve generated code performance (e.g. as I remember it improved SPECFP2000 by 1% for ppc64). So I guess, it should mark as such in order to see this possibility to improve the code by a programmer.
