[PATCH, MIPS] Ensure softfloat and single float take precendence in consistency checks

[Matthew Fortune]

Richard Sandiford <rdsandiford@googlemail.com> writes:
> Matthew Fortune <Matthew.Fortune@imgtec.com> writes:
> > This patch fixes a subtle mistake in the FP ABI consistency check
> > logic.  The error reporting does not currently follow the
> > intended precedence of the various FP ABIs. I.e. softfloat,
> > singlefloat and then all the hardfloat variants.  When someone
> > uses -msingle-float with a GNU attribute which is not 4,2 then
> > the initial warning should be that it is not compatible with
> > singlefloat. Likewise for softfloat and attribute 4,3.
> 
> I agree with checking soft/single/double before register size,
> but the patch still does it after checking -mabi.  Is that important?
> I've always thought of -mabi and -mgp/-mfp being a set so IMO it's more
> natural to check soft/single/double first, then ABI, then register size.
> E.g. if someone uses fpxx in a softfloat n32 then I think it's valid to
> report either the softfloatness or the n32ness being the problem.
> 
> It'd be cleaner to have just one copy of the code at the head of the
> function rather than duplicate it in each case statement.

I think that sounds OK. I just had myself focussed on keeping the
O32-only ABI extensions restricted to O32 but ordering does not matter
for this particular piece of code.

Thanks,
Matthew