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From: "crazylht at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/109048] [13 regression] redundant mask compare generated by vectorizer.
Date: Tue, 07 Mar 2023 06:34:06 +0000	[thread overview]
Message-ID: <bug-109048-4-K6NVnV1GEZ@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-109048-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109048

--- Comment #4 from Hongtao.liu <crazylht at gmail dot com> ---
(In reply to Hongtao.liu from comment #3)
> A three-operand phi make ifcvt generate worse code
> 
It saved 1 add for potential 1.f + 0.f/1.f since it's constant, but generates
more logic operations for predicates.

Hmm, it looks good for scalar since it's just compare and jump, but hurt
vectorization due to more logical operations for predicates.

  parent reply	other threads:[~2023-03-07  6:34 UTC|newest]

Thread overview: 14+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-03-07  6:01 [Bug tree-optimization/109048] New: " crazylht at gmail dot com
2023-03-07  6:03 ` [Bug tree-optimization/109048] " crazylht at gmail dot com
2023-03-07  6:13 ` crazylht at gmail dot com
2023-03-07  6:22 ` crazylht at gmail dot com
2023-03-07  6:34 ` crazylht at gmail dot com [this message]
2023-03-07  9:17 ` rguenth at gcc dot gnu.org
2023-03-07  9:38 ` jakub at gcc dot gnu.org
2023-03-07 10:09 ` rguenther at suse dot de
2023-03-27  8:26 ` rguenth at gcc dot gnu.org
2023-03-27  9:18 ` rguenth at gcc dot gnu.org
2023-03-27 10:37 ` rguenth at gcc dot gnu.org
2023-03-28 12:20 ` rguenth at gcc dot gnu.org
2023-04-13  7:30 ` rguenth at gcc dot gnu.org
2023-04-13  8:14 ` crazylht at gmail dot com

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