> I'm forced to fall back to a targeted patch in > calls.c:precompute_register_parameters() that tests exactly for TLS > symbols on AIX instead of using the legitimate_constant_p hook to test > for TLS symbols. > > I could create a new target hook for this specific use in calls.c and > define it as an alias to legitimate_constant_p for all other targets, > but that solution seems overkill for a very narrow and target-specific > issue. No other target will override this hook.
That would not be the first example I think. Defining a new target hook doesn't mean touching the other back-ends: you put a default in target.def which lives in targhooks.c and just calls targetm.legitimate_constant_p, so you only need to patch target.def, targhooks.c and targhooks.h. -- Eric Botcazou