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Re: patch: vector register arguments


On Fri, 2001-11-02 at 21:17, Richard Henderson wrote:
> On Fri, Nov 02, 2001 at 01:48:38PM -0500, Aldy Hernandez wrote:
> > Without wider mode information, gcc is unable to determine how to
> > store a given vector register if the narrowest vector mode (V2SF or
> > V2QI) does not exist in the given target.  Gcc will try to iterate to
> > get a wider mode, and unable to find one that fits, aborts.
> 
> I don't think it makes sense to have wider mode for vectors.
> What does that mean, exactly?  If it just means "here's a way


yeah, it doesn't make much sense from a "wider" perspective.  i looked
at other places where we use GET_MODE_WIDER_MODE et al, and never do we
handle vector modes.  so i was thinking it wouldn't hurt since we don't
do any operations vectors (apart from moving them).  this could change
in the future though.

i see no clear way of implementing apply_*_size() without having to add
other fields in machmode.def, or perhaps another table altogether with
pointers so we can iterate through vectors.

> to iterate over the lot of them", then I think that should be
> clearly documented somewhere.

can i add documentation in the DEF_MACHMODE docs at the head of
machmode.def?

> 
> 
> r~
-- 
Aldy Hernandez			E-mail: aldyh@redhat.com
Professional Gypsy
Red Hat, Inc.


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