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From: "jason at zx2c4 dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug target/103252] questionable codegen with kmovd
Date: Tue, 16 Nov 2021 11:51:06 +0000	[thread overview]
Message-ID: <bug-103252-4-wCqgfP26Nu@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 #7 from Jason A. Donenfeld <jason at zx2c4 dot com> ---
The strange thing in this case is that the non-avx512 codegen _doesn't_ spill
to memory. It just uses the gprs that are around. So it seems like that,
somehow, the mere existence of the mask registers causes the register allocator
to be lazier than usual, resulting in this situation, where the effects combine
to produce suboptimal code.

  parent reply	other threads:[~2021-11-16 11:51 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 [this message]
2021-11-16 11:56 ` jakub at gcc dot gnu.org
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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