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Date:   Wed, 13 Dec 2023 08:52:01 +0100
From:   "Arnd Bergmann" <arnd@arndb.de>
To:     "Charlie Jenkins" <charlie@rivosinc.com>,
        "Palmer Dabbelt" <palmer@dabbelt.com>,
        "Conor Dooley" <conor@kernel.org>,
        "Samuel Holland" <samuel.holland@sifive.com>,
        "David Laight" <David.Laight@aculab.com>,
        "Xiao W Wang" <xiao.w.wang@intel.com>,
        "Evan Green" <evan@rivosinc.com>, linux-riscv@lists.infradead.org,
        linux-kernel@vger.kernel.org,
        Linux-Arch <linux-arch@vger.kernel.org>
Cc:     "Paul Walmsley" <paul.walmsley@sifive.com>,
        "Albert Ou" <aou@eecs.berkeley.edu>
Subject: Re: [PATCH v12 1/5] asm-generic: Improve csum_fold
Content-Type: text/plain
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On Wed, Dec 13, 2023, at 02:18, Charlie Jenkins wrote:
> This csum_fold implementation introduced into arch/arc by Vineet Gupta
> is better than the default implementation on at least arc, x86, and
> riscv. Using GCC trunk and compiling non-inlined version, this
> implementation has 41.6667%, 25% fewer instructions on riscv64, x86-64
> respectively with -O3 optimization. Most implmentations override this
> default in asm, but this should be more performant than all of those
> other implementations except for arm which has barrel shifting and
> sparc32 which has a carry flag.
>
> Signed-off-by: Charlie Jenkins <charlie@rivosinc.com>

Acked-by: Arnd Bergmann <arnd@arndb.de>