[Bug target/43440] Overwriting neon quad register does not clobber all included single registers

[ramana at gcc dot gnu dot org]

------- Comment #9 from ramana at gcc dot gnu dot org  2010-03-21 13:41 -------
(In reply to comment #8)
> What about just forbidding to use "q" registers in the inline assembly clobber
> list? Is it difficult to do?
> 

It's not difficult to - 

The patch only penalises the cases where an s<reg> ends up clobbering another
s<reg> in the same quad (or double for that matter) but the common case of the
q<reg> or the d<reg> clobbering the s<reg> in the same quad is a necessity and
correctness.  Thus if we wanted to allow q<reg> and d<reg> in the clobber list
then we need to live with this restriction.

Ramana


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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43440