RFC: PATCH: Remove 26 element limit in vector

[Kenneth Zadeck]

we hit this limit trying to write the explicit semantics for a 
vec_interleave_evenv32qi.

;;(define_insn "vec_interleave_evenv32qi"
;;  [(set (match_operand:V32QI 0 "register_operand" "=r")
;;    (vec_select:V32QI
;;      (vec_concat:V64QI
;;        (match_operand:V32QI 1 "register_operand" "0")
;;        (match_operand:V32QI 2 "register_operand" "r"))
;;      (parallel [(const_int  0) (const_int 32)
;;             (const_int  2) (const_int 34)
;;             (const_int  4) (const_int 36)
;;             (const_int  6) (const_int 38)
;;             (const_int  8) (const_int 40)
;;             (const_int 10) (const_int 42)
;;             (const_int 12) (const_int 44)
;;             (const_int 14) (const_int 46)
;;             (const_int 16) (const_int 48)
;;             (const_int 18) (const_int 50)
;;             (const_int 20) (const_int 52)
;;             (const_int 22) (const_int 54)
;;             (const_int 24) (const_int 56)
;;             (const_int 26) (const_int 58)
;;             (const_int 28) (const_int 60)
;;             (const_int 30) (const_int 62)])))]
;;  ""
;;  "rimihv\t%0,%2,8,15,8"
;;  [(set_attr "type" "rimi")])


kenny

On 03/31/2011 06:16 AM, Mike Stump wrote:
> On Mar 31, 2011, at 1:41 AM, Richard Guenther wrote:
>> On Wed, Mar 30, 2011 at 8:09 PM, H.J. Lu<hongjiu.lu@intel.com>  wrote:
>>> On Wed, Mar 30, 2011 at 08:02:38AM -0700, H.J. Lu wrote:
>>>> Hi,
>>>>
>>>> Currently, we limit XVECEXP to 26 elements in machine description
>>>> since we use letters 'a' to 'z' to encode them.  I don't see any
>>>> reason why we can't go beyond 'z'.  This patch removes this restriction.
>>>> Any comments?
>>>>
>>> That was wrong.  The problem is in vector elements.  This patch passes
>>> bootstrap.  Any comments?
>> Do you really need it?
> I'm trying to recall if this is the limit Kenny and I hit....  If so, annoying.  Kenny could confirm if it was.  gcc's general strategy of, no fixed N gives gcc a certain flexibility that is very nice to have, on those general grounds, I kinda liked this patch.