Re: [FFmpeg-devel] [PATCH 3/3] lavc/svq1enc: R-V V ssd_int8_vs_int16

[flow gg <hlefthleft@gmail.com>]

[-- Attachment #1: Type: text/plain, Size: 1794 bytes --]

Alright, I learned a bit more, so should we not consider the internal
implementation?
I've added this version that reduces one vset in this reply.

Rémi Denis-Courmont <remi@remlab.net> 于2024年1月7日周日 16:03写道：

> Le sunnuntaina 7. tammikuuta 2024, 3.33.39 EET flow gg a écrit :
> > I tested it, and indeed using vwsub is faster. Updated it in the reply.
> >
> > ---
> >
> > I have a question: if I tweak the load order a bit, using one less vset,
> it
> > leads to being slower (the patch I submitted is 13.2, if I make the
> > following change, the time would be 15.2).
> > But I thought it would be faster.
>
> I would guess that v0 is needed before v8 in the internal implementation
> of
> vwsub. This kind of makes sense as the element still need to be
> sign-extended.
> Thus vwsub ends up stalling the pipeline in wait for vle8 to complete.
> That's
> just a guess though, as I don't have internal cycle timing documentation.
>
> > - vsetvli      t0, a2, e8, m2, tu, ma
> > - vle8.v       v0, (a0)
> > - sub          a2, a2, t0
> > - vsetvli      zero, t0, e16, m4, tu, ma
> > - vle16.v      v8, (a1)
> > - vsetvli      zero, t0, e8, m2, tu, ma
> > - vwsub.wv     v16, v8, v0
> >
> > + vsetvli      t0, a2, e16, m4, tu, ma
> > + vle16.v      v8, (a1)
> > + sub          a2, a2, t0
> > + vsetvli      zero, t0, e8, m2, tu, ma
> > + vle8.v       v0, (a0)
> > + vwsub.wv     v16, v8, v0
>
> --
> 雷米‧德尼-库尔蒙
> http://www.remlab.net/
>
>
>
> _______________________________________________
> 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".
>

[-- Attachment #2: 0003-lavc-svq1enc-R-V-V-ssd_int8_vs_int16.patch --]
[-- Type: text/x-patch, Size: 5551 bytes --]

From 786c28b1c83b3cf033644c54ff32240f07b8082b Mon Sep 17 00:00:00 2001
From: sunyuechi <sunyuechi@iscas.ac.cn>
Date: Fri, 29 Dec 2023 13:27:31 +0800
Subject: [PATCH 3/3] lavc/svq1enc: R-V V ssd_int8_vs_int16

C908
ssd_int8_vs_int16_c: 207.7
ssd_int8_vs_int16_rvv_i32: 15.2
---
 libavcodec/riscv/Makefile      |  2 ++
 libavcodec/riscv/svqenc_init.c | 41 +++++++++++++++++++++++++++++++
 libavcodec/riscv/svqenc_rvv.S  | 44 ++++++++++++++++++++++++++++++++++
 libavcodec/svq1enc.c           |  2 ++
 libavcodec/svq1encdsp.h        |  1 +
 5 files changed, 90 insertions(+)
 create mode 100644 libavcodec/riscv/svqenc_init.c
 create mode 100644 libavcodec/riscv/svqenc_rvv.S

diff --git a/libavcodec/riscv/Makefile b/libavcodec/riscv/Makefile
index 7f253bba12..4e14c3d094 100644
--- a/libavcodec/riscv/Makefile
+++ b/libavcodec/riscv/Makefile
@@ -46,6 +46,8 @@ RVV-OBJS-$(CONFIG_OPUS_DECODER) += riscv/opusdsp_rvv.o
 OBJS-$(CONFIG_PIXBLOCKDSP) += riscv/pixblockdsp_init.o
 RV-OBJS-$(CONFIG_PIXBLOCKDSP) += riscv/pixblockdsp_rvi.o
 RVV-OBJS-$(CONFIG_PIXBLOCKDSP) += riscv/pixblockdsp_rvv.o
+OBJS-$(CONFIG_SVQ1_ENCODER) += riscv/svqenc_init.o
+RVV-OBJS-$(CONFIG_SVQ1_ENCODER) += riscv/svqenc_rvv.o
 OBJS-$(CONFIG_TAK_DECODER) += riscv/takdsp_init.o
 RVV-OBJS-$(CONFIG_TAK_DECODER) += riscv/takdsp_rvv.o
 OBJS-$(CONFIG_UTVIDEO_DECODER) += riscv/utvideodsp_init.o
diff --git a/libavcodec/riscv/svqenc_init.c b/libavcodec/riscv/svqenc_init.c
new file mode 100644
index 0000000000..f4c398960c
--- /dev/null
+++ b/libavcodec/riscv/svqenc_init.c
@@ -0,0 +1,41 @@
+/*
+ * Copyright (c) 2023 Institue of Software Chinese Academy of Sciences (ISCAS).
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "config.h"
+
+#include "libavutil/attributes.h"
+#include "libavutil/cpu.h"
+#include "libavcodec/svq1encdsp.h"
+
+int ff_ssd_int8_vs_int16_rvv(const int8_t *pix1, const int16_t *pix2,
+                              intptr_t size);
+
+av_cold void ff_svq1enc_init_riscv(SVQ1EncDSPContext *c)
+{
+#if HAVE_RVV
+    int flags = av_get_cpu_flags();
+
+    if (flags & AV_CPU_FLAG_RVV_I32) {
+        if (flags & AV_CPU_FLAG_RVB_ADDR) {
+            c->ssd_int8_vs_int16 = ff_ssd_int8_vs_int16_rvv;
+        }
+    }
+#endif
+}
diff --git a/libavcodec/riscv/svqenc_rvv.S b/libavcodec/riscv/svqenc_rvv.S
new file mode 100644
index 0000000000..b632eb39a9
--- /dev/null
+++ b/libavcodec/riscv/svqenc_rvv.S
@@ -0,0 +1,44 @@
+/*
+ * Copyright (c) 2023 Institue of Software Chinese Academy of Sciences (ISCAS).
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "libavutil/riscv/asm.S"
+
+func ff_ssd_int8_vs_int16_rvv, zve32x
+        vsetvli     t0, zero, e32, m8, ta, ma
+        vmv.v.x     v24, zero
+1:
+        vsetvli      t0, a2, e16, m4, tu, ma
+        vle16.v      v8, (a1)
+        sub          a2, a2, t0
+        vsetvli      zero, t0, e8, m2, tu, ma
+        vle8.v       v0, (a0)
+        vwsub.wv     v16, v8, v0
+        vsetvli      zero, t0, e16, m4, tu, ma
+        add          a0, a0, t0
+        vwmacc.vv    v24, v16, v16
+        sh1add       a1, t0, a1
+        bnez         a2, 1b
+        vsetvli      t0, zero, e32, m8, ta, ma
+        vmv.s.x      v0, zero
+        vredsum.vs   v0, v24, v0
+        vmv.x.s      a0, v0
+
+        ret
+endfunc
diff --git a/libavcodec/svq1enc.c b/libavcodec/svq1enc.c
index 0dea405dec..6e7ea12aa7 100644
--- a/libavcodec/svq1enc.c
+++ b/libavcodec/svq1enc.c
@@ -766,6 +766,8 @@ void ff_svq1enc_init(SVQ1EncDSPContext *c)
 
 #if ARCH_PPC
     ff_svq1enc_init_ppc(c);
+#elif ARCH_RISCV
+    ff_svq1enc_init_riscv(c);
 #elif ARCH_X86
     ff_svq1enc_init_x86(c);
 #endif
diff --git a/libavcodec/svq1encdsp.h b/libavcodec/svq1encdsp.h
index 618bf8463b..5dfa35cc62 100644
--- a/libavcodec/svq1encdsp.h
+++ b/libavcodec/svq1encdsp.h
@@ -30,6 +30,7 @@ typedef struct SVQ1EncDSPContext {
 
 void ff_svq1enc_init(SVQ1EncDSPContext *c);
 void ff_svq1enc_init_ppc(SVQ1EncDSPContext *c);
+void ff_svq1enc_init_riscv(SVQ1EncDSPContext *c);
 void ff_svq1enc_init_x86(SVQ1EncDSPContext *c);
 
 #endif /* AVCODEC_SVQ1ENCDSP_H */
-- 
2.43.0


[-- Attachment #3: Type: text/plain, Size: 251 bytes --]

_______________________________________________
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".