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From: "roger at nextmovesoftware dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug rtl-optimization/110701] [14 Regression] Wrong code at -O1/2/3/s on x86_64-linux-gnu
Date: Tue, 18 Jul 2023 15:38:53 +0000	[thread overview]
Message-ID: <bug-110701-4-1HtZuXR3zc@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-110701-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110701

Roger Sayle <roger at nextmovesoftware dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |roger at nextmovesoftware dot com

--- Comment #5 from Roger Sayle <roger at nextmovesoftware dot com> ---
nonzero_bits ((reg:DI 92),SImode) is returning 340, so combine (or more
specifically simplify_and_const_int_1) believes that the AND (ZERO_EXTEND)
isn't unnecessary.  So it's the same nonzero_bits information that allows us to
turn the  XOR into IOR (in insn 16) that's incorrectly telling us the AND 340
(or AND 343, or ZERO_EXTEND) is unnecessary (in insn 17).

  parent reply	other threads:[~2023-07-18 15:38 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-07-17 10:21 [Bug c/110701] New: " shaohua.li at inf dot ethz.ch
2023-07-17 12:43 ` [Bug rtl-optimization/110701] [14 Regression] " xry111 at gcc dot gnu.org
2023-07-17 17:51 ` pinskia at gcc dot gnu.org
2023-07-17 17:55 ` pinskia at gcc dot gnu.org
2023-07-17 17:58 ` pinskia at gcc dot gnu.org
2023-07-18 15:38 ` roger at nextmovesoftware dot com [this message]
2023-07-18 17:17 ` roger at nextmovesoftware dot com
2023-07-27 18:23 ` roger at nextmovesoftware dot com
2023-10-04 16:12 ` cvs-commit at gcc dot gnu.org
2023-10-11  7:59 ` roger at nextmovesoftware dot com

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