Steve Ellcey <s...@cup.hp.com> writes: > On Fri, 2009-05-29 at 09:38 -0700, Ian Lance Taylor wrote: >> Steve Ellcey <s...@cup.hp.com> writes: >> >> > So instead of >> > if (flag_var_tracking) >> > we would have >> > if (targetm.get_optimization_flag_value(OPT_fvar_tracking)) >> >> I don't particularly want to have to make an indirect function call >> every time we check a flag. I don't see why we should check every time >> when we can determine the value once when the compiler starts. > > But if we want to fully support things like the __optimize__ attribute > then we can't just check once when the compiler starts. The flag could > be changed during compilation by the optimize attribute so at the very > least we need to override some values every time we see this attribute > (which is what we are not doing now).
Fair enough, but 99.9% of compilations will not use the __optimize__ attribute. So I still don't want to make an indirect function call every time we check a flag. Joseph's suggestion of a more disciplined approach to option interactions may be the way to go. We can at least handle many simple cases that way (this backend always enables/disables this option), while retaining a C function escape clause if there are complex ones. Ian
