public inbox for gcc-patches@gcc.gnu.org
 help / color / mirror / Atom feed
From: Jeff Law <jeffreyalaw@gmail.com>
To: 钟居哲 <juzhe.zhong@rivai.ai>, gcc-patches <gcc-patches@gcc.gnu.org>
Cc: "kito.cheng" <kito.cheng@gmail.com>,
	"kito.cheng" <kito.cheng@sifive.com>, palmer <palmer@dabbelt.com>,
	palmer <palmer@rivosinc.com>, "rdapp.gcc" <rdapp.gcc@gmail.com>
Subject: Re: [PATCH] RISC-V: Support vfwnmacc/vfwmsac/vfwnmsac combine lowering
Date: Thu, 29 Jun 2023 17:43:20 -0600	[thread overview]
Message-ID: <38937362-3401-b92e-cb9c-268e52451af7@gmail.com> (raw)
In-Reply-To: <AC4B7DA7E6E610C6+202306290656359649830@rivai.ai>



On 6/28/23 16:56, 钟居哲 wrote:
> 
> 
> ------------------------------------------------------------------------
> juzhe.zhong@rivai.ai
> 
>     *From:* Jeff Law <mailto:jeffreyalaw@gmail.com>
>     *Date:* 2023-06-29 06:43
>     *To:* 钟居哲 <mailto:juzhe.zhong@rivai.ai>; gcc-patches
>     <mailto:gcc-patches@gcc.gnu.org>
>     *CC:* kito.cheng <mailto:kito.cheng@gmail.com>; kito.cheng
>     <mailto:kito.cheng@sifive.com>; palmer <mailto:palmer@dabbelt.com>;
>     palmer <mailto:palmer@rivosinc.com>; rdapp.gcc
>     <mailto:rdapp.gcc@gmail.com>
>     *Subject:* Re: [PATCH] RISC-V: Support vfwnmacc/vfwmsac/vfwnmsac
>     combine lowering
>     On 6/28/23 16:10, 钟居哲 wrot
>      > Sure.
>      >
>      > https://godbolt.org/z/8857KzTno <https://godbolt.org/z/8857KzTno>
>      >
>      > Failed to match this instruction:
>      > (set (reg:VNx2DF 134 [ vect__31.47 ])
>      >      (fma:VNx2DF (neg:VNx2DF (float_extend:VNx2DF (reg:VNx2SF 136 [
>      > vect__28.44 ])))
>      >          (reg:VNx2DF 150 [ vect__8.12 ])
>      >          (reg:VNx2DF 171 [ vect__29.45 ])))
>     Please attach the full dump.  I would expect to see additional attempts
>     with more operands replaced.
THanks for the dump.  I think this fundamentally the same issue as the 
widening problem.

Drop those intermediate patterns.  They're not needed/helpful.  You may 
need a dependency height reduction pattern to get the code you want, but 
I see no evidence those extra patterns will solve anything.

jeff


  reply	other threads:[~2023-06-29 23:43 UTC|newest]

Thread overview: 13+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-06-28 11:55 Juzhe-Zhong
2023-06-28 18:16 ` Jeff Law
2023-06-28 22:10   ` 钟居哲
2023-06-28 22:43     ` Jeff Law
2023-06-28 22:56       ` 钟居哲
2023-06-29 23:43         ` Jeff Law [this message]
2023-06-30  1:14           ` juzhe.zhong
2023-06-30  1:26             ` Jeff Law
2023-06-30  1:32               ` juzhe.zhong
2023-07-03  7:48                 ` Robin Dapp
2023-07-03  9:01                   ` Kito Cheng
2023-07-03  9:12                     ` juzhe.zhong
2023-07-03  9:27                       ` Lehua Ding

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=38937362-3401-b92e-cb9c-268e52451af7@gmail.com \
    --to=jeffreyalaw@gmail.com \
    --cc=gcc-patches@gcc.gnu.org \
    --cc=juzhe.zhong@rivai.ai \
    --cc=kito.cheng@gmail.com \
    --cc=kito.cheng@sifive.com \
    --cc=palmer@dabbelt.com \
    --cc=palmer@rivosinc.com \
    --cc=rdapp.gcc@gmail.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).