[Bug target/53101] Recognize casts to sub-vectors

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53101

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |missed-optimization
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2012-04-24
     Ever Confirmed|0                           |1

--- Comment #1 from Richard Guenther <rguenth at gcc dot gnu.org> 2012-04-24 11:13:33 UTC ---
We get MEM[(T * {ref-all})&x] for the casting (not a BIT_FIELD_REF for
example).
This gets expanded to

(insn 6 5 7 (set (reg:OI 63)
        (subreg:OI (reg/v:V4DF 61 [ x ]) 0)) t.c:8 -1
     (nil))

(insn 7 6 8 (set (reg:V2DF 60 [ <retval> ])
        (subreg:V2DF (reg:OI 63) 0)) t.c:8 -1
     (nil))

but that should be perfectly optimizable.