Question about vec_extract

[Jim Wilson]

Andrew Pinski wrote:
> I have been trying to figure out when the pattern vec_extract is
> invoked.

I looked at this when I worked on the mips simd support.  In 
config/mips/mips-ps-3d.md I wrote
;; ??? This is only generated if we perform a vector operation that has 
to be
;; emulated.  There is no other way to get a vector mode bitfield extract
;; currently.

So it can be generated, but you have to use a vector mode that doesn't 
exist on the target.  Which kind of defeats the purpose of having it. 
Anyways, I think all we need here is a little syntax to get the 
operation we want.  Maybe a builtin function or something.
-- 
Jim Wilson, GNU Tools Support, http://www.specifix.com