Re: [arm-gnu] How to write VFP inline asm with double precision register constraints?

[Richard Earnshaw <rearnsha@xxxxxxx>]

On Tue, 2010-08-24 at 07:52 -0700, Mark Mitchell wrote:
> Richard Earnshaw wrote:
> 
> > Some constraints are deliberately left
> > undocumented because we cannot commit to maintaining them as they
> > currently are: constraints are really internal properties of the machine
> > description files, not public interfaces.
> 
> I think that last clause applies with the same "some" qualifier as the
> first clause.  Documented constraints *are* public interfaces, given how
> GNU inline asm works.  Do you think "P" should remain undocumented?
> 

I actually think that it is unfortunate that any of this internal
interface is exported publicly.  But you are right, given the current
state of GCC.  There is a strong (I won't put it higher than that)
commitment to maintain the publicly documented constraints.  There is no
commitment to maintain any others.

R.