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From: "jakub at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug target/103252] questionable codegen with kmovd
Date: Tue, 16 Nov 2021 11:56:12 +0000	[thread overview]
Message-ID: <bug-103252-4-IM3LHMQobY@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-103252-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103252

--- Comment #8 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Definitely not lazier.  When the mask registers are available for use, RA
considers them and when spilling to those is cheaper than to memory, it spills
to them and not memory.  Where cheaper is determined by the gcc cost model,
which tries to approximately model the hw, but on real hw whether it is
beneficial or not may depend on various other details that perhaps aren't even
considered.

  parent reply	other threads:[~2021-11-16 11:56 UTC|newest]

Thread overview: 16+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-11-15 14:58 [Bug c/103252] New: " jason at zx2c4 dot com
2021-11-15 15:18 ` [Bug c/103252] " jason at zx2c4 dot com
2021-11-15 17:10 ` jason at zx2c4 dot com
2021-11-15 17:52 ` [Bug target/103252] " jakub at gcc dot gnu.org
2021-11-15 17:59 ` pinskia at gcc dot gnu.org
2021-11-15 18:07 ` jason at zx2c4 dot com
2021-11-16  1:20 ` crazylht at gmail dot com
2021-11-16  9:29 ` rguenth at gcc dot gnu.org
2021-11-16 11:51 ` jason at zx2c4 dot com
2021-11-16 11:56 ` jakub at gcc dot gnu.org [this message]
2021-11-16 12:06 ` jason at zx2c4 dot com
2021-11-18  7:09 ` crazylht at gmail dot com
2021-11-18  8:26 ` crazylht at gmail dot com
2021-11-19  2:42 ` crazylht at gmail dot com
2021-11-19  6:27 ` crazylht at gmail dot com
2021-11-24  5:47 ` crazylht at gmail dot com

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