On Wed, Jun 1, 2011 at 1:37 PM, Ira Rosen <ira.ro...@linaro.org> wrote:
> On 1 June 2011 12:42, Richard Guenther <richard.guent...@gmail.com> wrote:
>
>> Did you think about moving pass_optimize_widening_mul before
>> loop optimizations? Does that pass catch the cases you are
>> teaching the pattern recognizer? I think we should try to expose
>> these more complicated instructions to loop optimizers.
>>
>
> pass_optimize_widening_mul doesn't catch these cases, but I can try to
> teach it instead of the vectorizer.
> I am now testing
>
> Index: passes.c
> ===================================================================
> --- passes.c (revision 174391)
> +++ passes.c (working copy)
> @@ -870,6 +870,7 @@
> NEXT_PASS (pass_split_crit_edges);
> NEXT_PASS (pass_pre);
> NEXT_PASS (pass_sink_code);
> + NEXT_PASS (pass_optimize_widening_mul);
> NEXT_PASS (pass_tree_loop);
> {
> struct opt_pass **p = &pass_tree_loop.pass.sub;
> @@ -934,7 +935,6 @@
> NEXT_PASS (pass_forwprop);
> NEXT_PASS (pass_phiopt);
> NEXT_PASS (pass_fold_builtins);
> - NEXT_PASS (pass_optimize_widening_mul);
> NEXT_PASS (pass_tail_calls);
> NEXT_PASS (pass_rename_ssa_copies);
> NEXT_PASS (pass_uncprop);
>
> to see how it affects other loop optimizations (vectorizer pattern
> tests obviously fail).
Thanks. I would hope that we eventually can get rid of the
pattern recognizer ... at least for SSE there is also always
a scalar variant instruction for each vectorized one.
Richard.
