On Mon, Dec 12, 2011 at 3:05 AM, Rohit Arul Raj <rohitarul...@gmail.com> wrote:
> And with ‘-O3’ and above, we cannot switch OFF the flag > ‘-fira-loop-pressure’, because it has been explicitly overridden in > the PPC backend target files. > > 1) Is it possible to update the heuristic to allow this optimization. > 2) If not, the user should have control over the '-fira-loop-pressure' > flag when passed explicitly. > > File: rs6000.c > if (optimize >= 3 && global_init_p && > !global_options_set.x_flag_ira_loop_pressure) > flag_ira_loop_pressure = 1; The rs6000 port should allow this option to be overridden. It would be better to post an explicit, tested patch to the gcc-patches mailinglist. The cost model is a separate issue that also should be corrected to not inhibit this transformation. Thanks, David
