From: Richard Biener <richard.guenther@gmail.com>
To: "Kewen.Lin" <linkw@linux.ibm.com>
Cc: GCC Patches <gcc-patches@gcc.gnu.org>,
Bill Schmidt <wschmidt@linux.ibm.com>,
Segher Boessenkool <segher@kernel.crashing.org>,
Richard Sandiford <richard.sandiford@arm.com>
Subject: Re: [PATCH v2] vect/rs6000: Support vector with length cost modeling
Date: Wed, 22 Jul 2020 08:38:40 +0200 [thread overview]
Message-ID: <CAFiYyc17sDdBAPpFWo9PJr83EC_ZJEMwJ_ZobJOCJxLLhRymmg@mail.gmail.com> (raw)
In-Reply-To: <a06e714e-04c3-8a2f-fa1d-02a72aecf7f4@linux.ibm.com>
On Wed, Jul 22, 2020 at 3:26 AM Kewen.Lin <linkw@linux.ibm.com> wrote:
>
> Hi Richard,
>
> on 2020/7/21 下午3:57, Richard Biener wrote:
> > On Tue, Jul 21, 2020 at 7:52 AM Kewen.Lin <linkw@linux.ibm.com> wrote:
> >>
> >> Hi,
> >>
> >> This patch is to add the cost modeling for vector with length,
> >> it mainly follows what we generate for vector with length in
> >> functions vect_set_loop_controls_directly and vect_gen_len
> >> at the worst case.
> >>
> >> For Power, the length is expected to be in bits 0-7 (high bits),
> >> we have to model the cost of shifting bits. To allow other targets
> >> not suffer this, I used one target hook to describe this extra cost,
> >> I'm not sure if it's a correct way.
> >>
> >> Bootstrapped/regtested on powerpc64le-linux-gnu (P9) with explicit
> >> param vect-partial-vector-usage=1.
> >>
> >> Any comments/suggestions are highly appreciated!
> >
> > I don't like the introduction of an extra target hook for this. All
> > vectorizer cost modeling should ideally go through
> > init_cost/add_stmt_cost/finish_cost. If the extra costing is
> > not per stmt then either init_cost or finish_cost is appropriate.
> > Currently init_cost only gets a struct loop while we should
> > probably give it a vec_info * parameter so targets can
> > check LOOP_VINFO_USING_PARTIAL_VECTORS_P and friends.
> >
>
> Thanks! Nice, your suggested way looks better. I've removed the hook
> and taken care of it in finish_cost. The updated v2 is attached.
>
> Bootstrapped/regtested again on powerpc64le-linux-gnu (P9) with explicit
> param vect-partial-vector-usage=1.
LGTM (with assuming the first larger hunk is mostly re-indenting
under LOOP_VINFO_USING_PARTIAL_VECTORS_P).
Thanks,
Richard.
> BR,
> Kewen
> -----
> gcc/ChangeLog:
>
> * config/rs6000/rs6000.c (adjust_vect_cost): New function.
> (rs6000_finish_cost): Call function adjust_vect_cost.
> * tree-vect-loop.c (vect_estimate_min_profitable_iters): Add cost
> modeling for vector with length.
next prev parent reply other threads:[~2020-07-22 6:38 UTC|newest]
Thread overview: 23+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-07-21 5:51 [PATCH] vect: " Kewen.Lin
2020-07-21 7:57 ` Richard Biener
2020-07-22 1:26 ` [PATCH v2] vect/rs6000: " Kewen.Lin
2020-07-22 6:38 ` Richard Biener [this message]
2020-07-22 7:08 ` Kewen.Lin
2020-07-22 9:11 ` Richard Sandiford
2020-07-22 15:48 ` [PATCH v3] " Kewen.Lin
2020-07-22 16:25 ` Kewen.Lin
2020-07-24 16:21 ` Richard Sandiford
2020-07-27 3:58 ` [PATCH v4] " Kewen.Lin
2020-07-27 13:40 ` Richard Sandiford
2020-07-28 8:36 ` Kewen.Lin
2020-07-31 11:03 ` Richard Sandiford
2020-07-31 11:20 ` Richard Biener
2020-07-31 12:37 ` Kewen.Lin
2020-07-31 13:01 ` Richard Biener
2020-07-31 13:21 ` Kewen.Lin
2020-07-31 14:51 ` [PATCH v5] " Kewen.Lin
2020-08-05 7:27 ` Richard Sandiford
2020-08-05 14:06 ` Segher Boessenkool
2020-08-06 6:47 ` Kewen.Lin
2020-07-22 17:49 ` [PATCH v2] " Segher Boessenkool
2020-07-27 3:44 ` Kewen.Lin
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=CAFiYyc17sDdBAPpFWo9PJr83EC_ZJEMwJ_ZobJOCJxLLhRymmg@mail.gmail.com \
--to=richard.guenther@gmail.com \
--cc=gcc-patches@gcc.gnu.org \
--cc=linkw@linux.ibm.com \
--cc=richard.sandiford@arm.com \
--cc=segher@kernel.crashing.org \
--cc=wschmidt@linux.ibm.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).