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From: "munroesj at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug target/104124] Poor optimization for vector splat DW with small consts
Date: Wed, 19 Jan 2022 17:51:33 +0000	[thread overview]
Message-ID: <bug-104124-4-imMj8OsaGW@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-104124-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104124

Steven Munroe <munroesj at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |munroesj at gcc dot gnu.org

--- Comment #1 from Steven Munroe <munroesj at gcc dot gnu.org> ---
Created attachment 52236
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=52236&action=edit
Attempts to load small int consts to vector DW via splat

Multiple attempt to convince GCC to load small integer (-16 - 15) constants via
splat. Current GCC versions (9/10/11) convert vec_splats(<small const>) and
explicit vec_splat_s32/vec_unpackl sequences into to loads from .rodata. This
generates more instruction, takes more cycles, and causes register pressure
that results in unnecessary spill/reload and load-hit-store rejects.

  reply	other threads:[~2022-01-19 17:51 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-01-19 17:40 [Bug target/104124] New: " munroesj at gcc dot gnu.org
2022-01-19 17:51 ` munroesj at gcc dot gnu.org [this message]
2022-01-27 20:11 ` [Bug target/104124] " munroesj at gcc dot gnu.org
2022-01-27 21:16 ` meissner at gcc dot gnu.org
2023-06-28  8:39 ` cvs-commit at gcc dot gnu.org
2023-06-28 20:21 ` munroesj at gcc dot gnu.org
2023-07-13  7:22 ` guihaoc at gcc dot gnu.org

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