[Bug target/108401] gcc defeats vector constant generation with intrinsics

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108401

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Last reconfirmed|                            |2023-01-16
             Status|UNCONFIRMED                 |NEW
     Ever confirmed|0                           |1

--- Comment #5 from Richard Biener <rguenth at gcc dot gnu.org> ---
Confirmed.  We expand from

  return { 71777214294589695, 71777214294589695, 71777214294589695,
71777214294589695 };

where we could reduce the DImode broadcast to a HImode one (if that exists).
But sure, the x86 backend could implement the intrinsic suggested way to
generate this particular pattern.

I'll also note that -O0 produces quite bad code here.