From: "Maciej W. Rozycki" <macro@orcam.me.uk>
To: Jeff Law <jeffreyalaw@gmail.com>
Cc: Philipp Tomsich <philipp.tomsich@vrull.eu>,
gcc-patches@gcc.gnu.org, Kito Cheng <kito.cheng@gmail.com>,
Christoph Muellner <christoph.muellner@vrull.eu>,
Palmer Dabbelt <palmer@rivosinc.com>,
Andrew Waterman <andrew@sifive.com>,
Vineet Gupta <vineetg@rivosinc.com>
Subject: Re: [RFC PATCH v1 08/10] ifcvt: add if-conversion to conditional-zero instructions
Date: Tue, 28 Feb 2023 16:42:26 +0000 (GMT) [thread overview]
Message-ID: <alpine.DEB.2.21.2302281637440.40278@angie.orcam.me.uk> (raw)
In-Reply-To: <90ef6883-397b-8e6a-1ecb-3663fe854ac7@gmail.com>
On Mon, 13 Feb 2023, Jeff Law via Gcc-patches wrote:
> 3. The canaonical conditional-zero-or-value assumes the target can do a
> generic SEQ/SNE of two register values. As you know, on RISC-V we have
> SEQZ/SNEZ. So we've added another fallback path to handle that case in
> noce_emit_condzero. You subtract the two values, then you can do an SEQZ/SNEZ
> on the result.
NB these machine operations are identical to MIPSr6 SELEQZ and SELNEZ
instructions (cf. ISA_HAS_SEL), so why can't we just duplicate what the
MIPS backend does? Or did the MIPS backend do something wrong here?
Maciej
next prev parent reply other threads:[~2023-02-28 16:42 UTC|newest]
Thread overview: 31+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-02-10 22:41 [RFC PATCH v1 00/10] RISC-V: Support the Zicond (conditional-operations) extension Philipp Tomsich
2023-02-10 22:41 ` [RFC PATCH v1 01/10] docs: Document a canonical RTL for a conditional-zero insns Philipp Tomsich
2023-02-10 23:18 ` Andrew Pinski
2023-02-10 22:41 ` [RFC PATCH v1 02/10] RISC-V: Recognize Zicond (conditional operations) extension Philipp Tomsich
2023-04-20 17:44 ` Jeff Law
2023-02-10 22:41 ` [RFC PATCH v1 03/10] RISC-V: Generate czero.eqz/nez on noce_try_store_flag_mask if-conversion Philipp Tomsich
2023-04-20 17:53 ` Jeff Law
2023-02-10 22:41 ` [RFC PATCH v1 04/10] RISC-V: Support immediates in Zicond Philipp Tomsich
2023-04-20 18:00 ` Jeff Law
2023-02-10 22:41 ` [RFC PATCH v1 05/10] RISC-V: Support noce_try_store_flag_mask as czero.eqz/czero.nez Philipp Tomsich
2023-04-21 19:31 ` Jeff Law
2023-02-10 22:41 ` [RFC PATCH v1 06/10] RISC-V: Recognize sign-extract + and cases for czero.eqz/nez Philipp Tomsich
2023-04-21 19:40 ` Jeff Law
2023-02-10 22:41 ` [RFC PATCH v1 07/10] RISC-V: Recognize bexti in negated if-conversion Philipp Tomsich
2023-04-21 19:56 ` Jeff Law
2023-02-10 22:41 ` [RFC PATCH v1 08/10] ifcvt: add if-conversion to conditional-zero instructions Philipp Tomsich
2023-02-10 23:07 ` Andrew Pinski
2023-02-13 17:32 ` Richard Sandiford
2023-02-13 18:43 ` Jeff Law
2023-02-13 18:53 ` Andrew Pinski
2023-02-13 7:31 ` Jeff Law
2023-02-28 16:42 ` Maciej W. Rozycki [this message]
2023-03-11 15:50 ` Jeff Law
2023-02-10 22:41 ` [RFC PATCH v1 09/10] RISC-V: Recognize xventanacondops extension Philipp Tomsich
2023-04-21 19:57 ` Jeff Law
2023-04-25 9:53 ` Kito Cheng
2023-04-25 10:15 ` Philipp Tomsich
2023-04-25 10:43 ` Kito Cheng
2023-04-26 2:28 ` Jeff Law
2023-02-10 22:41 ` [RFC PATCH v1 10/10] RISC-V: Support XVentanaCondOps extension Philipp Tomsich
2023-04-21 19:58 ` Jeff Law
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=alpine.DEB.2.21.2302281637440.40278@angie.orcam.me.uk \
--to=macro@orcam.me.uk \
--cc=andrew@sifive.com \
--cc=christoph.muellner@vrull.eu \
--cc=gcc-patches@gcc.gnu.org \
--cc=jeffreyalaw@gmail.com \
--cc=kito.cheng@gmail.com \
--cc=palmer@rivosinc.com \
--cc=philipp.tomsich@vrull.eu \
--cc=vineetg@rivosinc.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).