http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53513
--- Comment #10 from Oleg Endo <olegendo at gcc dot gnu.org> --- (In reply to Kazumoto Kojima from comment #9) > Although it seems that (1)-(5) in #3 are interesting points, they > are almost optimizations. Yep. Those are not necessary to get the functionality (of not using __fpscr_values). > I guess that programs with frequent FP > mode switchings are simply rare in real world and would be a bit > special or even pathological in the first place. > I like the idea of mode switching without __fpscr_values even if it > requires more instructions on SH4. Now SH4 is a fairy old core and > is not for heavy FP computations anyway. I think that it won't impact > the real working set. > It looks to me that Christian's patch is the way to go. Yep. However, when the patch was proposed there were some objections regarding the modifications in lcm.c (if I'm not mistaken). We could try again. The reason why I brought up (1)-(5) in #3 was that if one of them is eventually implemented (e.g. reorder calculation insns) the changes to lcm.c might not be required and could be avoided. Depending on the implementation of such optimization, the mode switch information might have to be obtained/maintained in a different way. However, I at the moment I have no concrete ideas/plans. If Christian's patch is accepted, that's cool, too.
