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.