From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from ffbox0-bg.mplayerhq.hu (ffbox0-bg.ffmpeg.org [79.124.17.100]) by master.gitmailbox.com (Postfix) with ESMTP id 7B8AE4398C for ; Thu, 4 Aug 2022 08:10:35 +0000 (UTC) Received: from [127.0.1.1] (localhost [127.0.0.1]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTP id CA29E68B93A; Thu, 4 Aug 2022 11:10:33 +0300 (EEST) Received: from mail8.parnet.fi (mail8.parnet.fi [77.234.108.134]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTPS id D813168B895 for ; Thu, 4 Aug 2022 11:10:27 +0300 (EEST) Received: from mail9.parnet.fi (mail9.parnet.fi [77.234.108.21]) by mail8.parnet.fi with ESMTP id 2748APZO018680-2748APZP018680; Thu, 4 Aug 2022 11:10:25 +0300 Received: from foo.martin.st (host-97-187.parnet.fi [77.234.97.187]) by mail9.parnet.fi (Postfix) with ESMTPS id A61B1A1468; Thu, 4 Aug 2022 11:10:25 +0300 (EEST) Date: Thu, 4 Aug 2022 11:10:25 +0300 (EEST) From: =?ISO-8859-15?Q?Martin_Storsj=F6?= To: Hubert Mazur In-Reply-To: <20220725112116.46154-1-hum@semihalf.com> Message-ID: <799eb635-9b2-944d-c396-9db820efe0a1@martin.st> References: <20220715080228.686736-6-hum@semihalf.com> <20220725112116.46154-1-hum@semihalf.com> MIME-Version: 1.0 X-FE-Policy-ID: 3:14:2:SYSTEM Subject: Re: [FFmpeg-devel] [PATCH] lavc/aarch64: Add neon implementation for pix_abs8 X-BeenThere: ffmpeg-devel@ffmpeg.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: FFmpeg development discussions and patches List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: FFmpeg development discussions and patches Cc: gjb@semihalf.com, upstream@semihalf.com, jswinney@amazon.com, ffmpeg-devel@ffmpeg.org, mw@semihalf.com, spop@amazon.com Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Errors-To: ffmpeg-devel-bounces@ffmpeg.org Sender: "ffmpeg-devel" Archived-At: List-Archive: List-Post: On Mon, 25 Jul 2022, Hubert Mazur wrote: > Provide optimized implementation of pix_abs8 function for arm64. > > Performance comparison tests are shown below. > - pix_abs_1_0_c: 105.2 > - pix_abs_1_0_neon: 21.4 > - sad_1_c: 107.2 > - sad_1_neon: 20.9 > > Benchmarks and tests are run with checkasm tool on AWS Graviton 3. > --- > libavcodec/aarch64/me_cmp_init_aarch64.c | 4 ++ > libavcodec/aarch64/me_cmp_neon.S | 53 ++++++++++++++++++++++++ > 2 files changed, 57 insertions(+) > > diff --git a/libavcodec/aarch64/me_cmp_init_aarch64.c b/libavcodec/aarch64/me_cmp_init_aarch64.c > index 89c817990c..7d7dc38754 100644 > --- a/libavcodec/aarch64/me_cmp_init_aarch64.c > +++ b/libavcodec/aarch64/me_cmp_init_aarch64.c > @@ -31,6 +31,8 @@ int ff_pix_abs16_x2_neon(MpegEncContext *v, uint8_t *pix1, uint8_t *pix2, > ptrdiff_t stride, int h); > int ff_pix_abs16_y2_neon(MpegEncContext *v, uint8_t *pix1, uint8_t *pix2, > ptrdiff_t stride, int h); > +int ff_pix_abs8_neon(MpegEncContext *s, uint8_t *blk1, uint8_t *blk2, > + ptrdiff_t stride, int h); > > int sse16_neon(MpegEncContext *v, uint8_t *pix1, uint8_t *pix2, > ptrdiff_t stride, int h); > @@ -48,8 +50,10 @@ av_cold void ff_me_cmp_init_aarch64(MECmpContext *c, AVCodecContext *avctx) > c->pix_abs[0][1] = ff_pix_abs16_x2_neon; > c->pix_abs[0][2] = ff_pix_abs16_y2_neon; > c->pix_abs[0][3] = ff_pix_abs16_xy2_neon; > + c->pix_abs[1][0] = ff_pix_abs8_neon; > > c->sad[0] = ff_pix_abs16_neon; > + c->sad[1] = ff_pix_abs8_neon; > c->sse[0] = sse16_neon; > c->sse[1] = sse8_neon; > c->sse[2] = sse4_neon; > diff --git a/libavcodec/aarch64/me_cmp_neon.S b/libavcodec/aarch64/me_cmp_neon.S > index dcaffc9b73..f2dd63ced1 100644 > --- a/libavcodec/aarch64/me_cmp_neon.S > +++ b/libavcodec/aarch64/me_cmp_neon.S > @@ -72,6 +72,59 @@ function ff_pix_abs16_neon, export=1 > ret > endfunc > > +function ff_pix_abs8_neon, export=1 > + // x0 unused > + // x1 uint8_t *pix1 > + // x2 uint8_t *pix2 > + // x3 ptrdiff_t stride > + // x4 int h > + > + movi d18, #0 > + cmp w4, #4 > + b.lt 2f > + > +// make 4 iterations at once > +1: > + ld1 {v0.8b}, [x1], x3 // Load pix1 for first iteration > + ld1 {v1.8b}, [x2], x3 // Load pix2 for first iteration > + uabdl v30.8h, v0.8b, v1.8b // Absolute difference, first iteration > + ld1 {v2.8b}, [x1], x3 // Load pix1 for second iteration > + ld1 {v3.8b}, [x2], x3 // Load pix2 for second iteration > + uabal v30.8h, v2.8b, v3.8b // Absolute difference, second iteration > + ld1 {v4.8b}, [x1], x3 // Load pix1 for third iteration > + ld1 {v5.8b}, [x2], x3 // Load pix2 for third iteration > + uabal v30.8h, v4.8b, v5.8b // Absolute difference, third iteration > + ld1 {v6.8b}, [x1], x3 // Load pix1 for foruth iteration > + ld1 {v7.8b}, [x2], x3 // Load pix2 for fourth iteration > + uabal v30.8h, v6.8b, v7.8b // Absolute difference, foruth iteration This is maybe the simplest example so far, where the unrolled version here just is 4 identical serial copies of the same set of 3 instructions; this maybe helps a bit on some CPUs, but it doesn't help nearly as much as it can on others, if it would be better unrolled. I.e., same comments as for the other patches; improve interleaving, don't do uaddlv once per iteration. // Martin _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-request@ffmpeg.org with subject "unsubscribe".