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From: Andreas Schwab <schwab@linux-m68k.org>
To: Akira Tsukamoto <akira.tsukamoto@gmail.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>,
	Palmer Dabbelt <palmer@dabbelt.com>,
	Guenter Roeck <linux@roeck-us.net>,
	Geert Uytterhoeven <geert@linux-m68k.org>,
	Qiu Wenbo <qiuwenbo@kylinos.com.cn>,
	Albert Ou <aou@eecs.berkeley.edu>,
	linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 1/1] riscv: __asm_copy_to-from_user: Improve using word copy if size < 9*SZREG
Date: Sun, 15 Aug 2021 08:51:18 +0200	[thread overview]
Message-ID: <87bl5z42vt.fsf@linux-m68k.org> (raw)
In-Reply-To: <e3e9fb3a-40b1-50f3-23cc-50bfa53baa8d@gmail.com> (Akira Tsukamoto's message of "Fri, 30 Jul 2021 22:52:44 +0900")

On Jul 30 2021, Akira Tsukamoto wrote:

>  .Lword_copy:
> -        /*
> -	 * Both src and dst are aligned, unrolled word copy
> +	/*
> +	 * Both src and dst are aligned
> +	 * None unrolled word copy with every 1*SZREG iteration
> +	 *
> +	 * a0 - start of aligned dst
> +	 * a1 - start of aligned src
> +	 * t0 - end of aligned dst
> +	 */
> +	bgeu	a0, t0, .Lbyte_copy_tail /* check if end of copy */
> +	addi	t0, t0, -(SZREG) /* not to over run */
> +1:
> +	REG_L	a5, 0(a1)
> +	addi	a1, a1, SZREG
> +	REG_S	a5, 0(a0)
> +	addi	a0, a0, SZREG
> +	bltu	a0, t0, 1b

This is missing fixups.

Andreas.

-- 
Andreas Schwab, schwab@linux-m68k.org
GPG Key fingerprint = 7578 EB47 D4E5 4D69 2510  2552 DF73 E780 A9DA AEC1
"And now for something completely different."

  parent reply	other threads:[~2021-08-15  6:51 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-07-30 13:50 [PATCH 0/1] __asm_copy_to-from_user: Reduce more byte_copy Akira Tsukamoto
2021-07-30 13:52 ` [PATCH 1/1] riscv: __asm_copy_to-from_user: Improve using word copy if size < 9*SZREG Akira Tsukamoto
2021-08-12 13:41   ` Guenter Roeck
2021-08-15  6:51   ` Andreas Schwab [this message]
2021-08-16 18:09   ` Palmer Dabbelt
2021-08-16 19:00     ` Andreas Schwab
2021-08-20  6:42       ` Akira Tsukamoto
2021-08-17  9:03     ` Akira Tsukamoto
2021-08-12 11:01 ` [PATCH 0/1] __asm_copy_to-from_user: Reduce more byte_copy Akira Tsukamoto
     [not found]   ` <61187c37.1c69fb81.ed9bd.cc45SMTPIN_ADDED_BROKEN@mx.google.com>
2021-08-16  6:24     ` Akira Tsukamoto
     [not found]       ` <611a33ac.1c69fb81.12aae.89a5SMTPIN_ADDED_BROKEN@mx.google.com>
2021-08-17  7:32         ` Akira Tsukamoto

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