[PATCH] Remove MISALIGNED_INDIRECT_REF

[Nathan Froyd]

On Thu, Sep 30, 2010 at 09:52:49AM -0400, Daniel Jacobowitz wrote:
> On Thu, Sep 30, 2010 at 03:11:47PM +0200, Eric Botcazou wrote:
> > > In experimenting with a STRICT_ALIGNMENT target, I noticed that
> > > the MEM rtx passed to the movmisalign expander sometimes has the
> > > default mode alignment, even though this is not true (that's why
> > > we need to use movmisalign in the first place).
> > 
> > But if you have movmisalign, why do you set STRICT_ALIGNMENT?  This seems to 
> > be the original contradiction.  You should use SLOW_UNALIGNED_ACCESS at most.
> 
> On ARM, for example, there are specific things that can be accessed
> "misaligned" - or at least with lower alignment requirements.  For
> instance, you can load V4SI with the alignment of SI.  But integer
> loads are still aligned only; this is a STRICT_ALIGNMENT target.

In a similar fashion--though GCC does not take advantage of this at the
moment--on E500 targets, the vector and FP instructions require
alignment, but integer instructions do not.  E500 is a STRICT_ALIGNMENT
target to cover the vector bits, but it would be beneficial if we could
move away from that.  From Richi's explanation of x86-64, such a thing
is certainly possible...

-Nathan