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From: "pinskia at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org> To: gcc-bugs@gcc.gnu.org Subject: [Bug target/114107] poor vectorization at -O3 when dealing with arrays of different multiplicity, good with -O2 Date: Sun, 25 Feb 2024 23:56:59 +0000 [thread overview] Message-ID: <bug-114107-4-NlbjgsfcVd@http.gcc.gnu.org/bugzilla/> (raw) In-Reply-To: <bug-114107-4@http.gcc.gnu.org/bugzilla/> https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114107 Andrew Pinski <pinskia at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Target| |x86_64-linux --- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> --- I am not 100% sure that is always better. What is happening is GCC is vectorizing even the outer loop. It is easier to understand via aarch64 asm too: .L4: ldr q27, [x3], 16 ld4 {v28.2d - v31.2d}, [x4] fmul v24.2d, v27.2d, v28.2d fmul v25.2d, v27.2d, v29.2d fmul v26.2d, v27.2d, v30.2d fmul v27.2d, v27.2d, v31.2d st4 {v24.2d - v27.2d}, [x4], 64 cmp x3, x5 bne .L4 Have you benchmarked both? If anything this is a cost model issue.
next prev parent reply other threads:[~2024-02-25 23:56 UTC|newest] Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top 2024-02-25 23:40 [Bug tree-optimization/114107] New: " nathanael.schaeffer at gmail dot com 2024-02-25 23:46 ` [Bug target/114107] " pinskia at gcc dot gnu.org 2024-02-25 23:56 ` pinskia at gcc dot gnu.org [this message] 2024-02-26 0:12 ` nathanael.schaeffer at gmail dot com 2024-02-26 0:13 ` nathanael.schaeffer at gmail dot com 2024-02-26 0:27 ` pinskia at gcc dot gnu.org 2024-02-26 0:34 ` nathanael.schaeffer at gmail dot com 2024-02-26 2:51 ` liuhongt at gcc dot gnu.org 2024-02-26 3:28 ` liuhongt at gcc dot gnu.org 2024-02-26 7:42 ` nathanael.schaeffer at gmail dot com 2024-02-26 7:49 ` nathanael.schaeffer at gmail dot com 2024-02-26 7:54 ` liuhongt at gcc dot gnu.org 2024-02-26 8:13 ` nathanael.schaeffer at gmail dot com 2024-02-26 9:10 ` [Bug tree-optimization/114107] " rguenth at gcc dot gnu.org 2024-02-26 14:40 ` rguenth at gcc dot gnu.org 2024-06-13 6:22 ` cvs-commit at gcc dot gnu.org 2024-06-13 7:13 ` rguenth at gcc dot gnu.org
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