Re: PATCH: Macroize SSE add/sub patterns

[Uros Bizjak <ubizjak at gmail dot com>]

H.J. Lu wrote:
> Hi,
>
> This patch macroizes SSE add/sub patterns. I am testing it
> on Linux/ia32 and Linux/Intel64. Ok for trunk if there are
> no regressions?
>   

Please see comments through the code. I think that we should extend 
existing code attributes to cover introduced sse_plusminus code 
iterator. Also, since this iterator can be used in mmx.md we should 
(IMO) add this iterator to i386.md, perhaps named sat_plusminus for 
"saturating" (sp?) operation.

> Thanks.
>
>
> H.J.
> ---
> 2008-05-05  H.J. Lu  <hongjiu.lu@intel.com>
>
>         * gcc/config/i386/sse.md (sse_plusminus): New.
>         (sse_plusminus_insn): Likewise.
>         (sse_plusminus_mnemonic): Likewise.
>         (sse_comm): Likewise.
>         (<addsub><mode>3): Likewise.
>         (*<addsub><mode>3): Likewise.
>         (sse2_<sse_plusminus_insn><mode>3): Likewise.
>         (add<mode>): Removed.
>         (*add<mode>3): Likewise.
>         (sse2_ssadd<mode>3): Likewise.
>         (sse2_usadd<mode>3): Likewise.
>         (sub<mode>3): Likewise.
>         (*sub<mode>3): Likewise.
>         (sse2_sssub<mode>3): Likewise.
>         (sse2_ussub<mode>3): Likewise.
>   
> ------------------------------------------------------------------------
>
> Index: gcc/config/i386/sse.md
> ===================================================================
> --- gcc/config/i386/sse.md	(revision 2431)
> +++ gcc/config/i386/sse.md	(working copy)
> @@ -18,6 +18,21 @@
>  ;; along with GCC; see the file COPYING3.  If not see
>  ;; <http://www.gnu.org/licenses/>.
>  
> +(define_code_iterator sse_plusminus [ss_plus us_plus ss_minus us_minus])
> +
> +;; Base name for define_insn.
> +(define_code_attr sse_plusminus_insn
> +  [(ss_plus "ssadd") (us_plus "usadd")
> +   (ss_minus "sssub") (us_minus "ussub")])
>   

We can perhaps rename expander names to fit extended addsub code 
attribute (see below).

> +
> +;; Base name for insn mnemonic.
> +(define_code_attr sse_plusminus_mnemonic
> +  [(ss_plus "adds") (us_plus "addus")
> +   (ss_minus "subs") (us_minus "subus")])
>   

The attribute above can be merged with existing addsub code attribute in 
i386.md.
> +
> +;; Mark SSE commutative operators as such in constraints.
> +(define_code_attr sse_comm [(ss_plus "%") (us_plus "%")
> +			    (ss_minus "") (us_minus "")])
>   

This one can be merged with existing comm code attribute in i386.md 
(please note, that there is no need for code attribute to cover exactly 
the range of relevant code iterator. In the case above, one code 
iterator "comm" can cover plusminunus as well as sse_plusminus code 
iterators. The same goes for extended addsub.

Thanks,
Uros.