lavc/vp8dsp: R-V V vp8_idct_dc_add

c908:
vp8_idct_dc_add_c: 102.2
vp8_idct_dc_add_rvv_i32: 42.0

Signed-off-by: Rémi Denis-Courmont <remi@remlab.net>

libavcodec/riscv/Makefile

@@ -54,5 +54,7 @@ OBJS-$(CONFIG_UTVIDEO_DECODER) += riscv/utvideodsp_init.o
 RVV-OBJS-$(CONFIG_UTVIDEO_DECODER) += riscv/utvideodsp_rvv.o
 OBJS-$(CONFIG_VC1DSP) += riscv/vc1dsp_init.o
 RVV-OBJS-$(CONFIG_VC1DSP) += riscv/vc1dsp_rvv.o
+OBJS-$(CONFIG_VP8DSP) += riscv/vp8dsp_init.o
+RVV-OBJS-$(CONFIG_VP8DSP) += riscv/vp8dsp_rvv.o
 OBJS-$(CONFIG_VORBIS_DECODER) += riscv/vorbisdsp_init.o
 RVV-OBJS-$(CONFIG_VORBIS_DECODER) += riscv/vorbisdsp_rvv.o

libavcodec/riscv/vp8dsp_init.c

@@ -0,0 +1,39 @@
+/*
+ * Copyright (c) 2024 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 "libavutil/riscv/cpu.h"
+#include "libavcodec/vp8dsp.h"
+
+void ff_vp8_idct_dc_add_rvv(uint8_t *dst, int16_t block[16], ptrdiff_t stride);
+
+av_cold void ff_vp8dsp_init_riscv(VP8DSPContext *c)
+{
+#if HAVE_RVV
+    int flags = av_get_cpu_flags();
+
+    if (flags & AV_CPU_FLAG_RVV_I32 && ff_get_rv_vlenb() >= 16) {
+        c->vp8_idct_dc_add = ff_vp8_idct_dc_add_rvv;
+    }
+#endif
+}

libavcodec/riscv/vp8dsp_rvv.S

@@ -0,0 +1,44 @@
+/*
+ * Copyright (c) 2024 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"
+
+.macro vp8_idct_dc_add
+        vlse32.v      v0, (a0), a2
+        lh            a5, 0(a1)
+        sh            zero, 0(a1)
+        addi          a5, a5, 4
+        srai          t1, a5, 3
+        vsetivli      zero, 4*4, e16, m2, ta, ma
+        vzext.vf2     v2, v0
+        vadd.vx       v2, v2, t1
+        vmax.vx       v2, v2, zero
+        vsetvli       zero, zero, e8, m1, ta, ma
+        vnclipu.wi    v0, v2, 0
+        vsetivli      zero, 4, e8, mf4, ta, ma
+        vsse32.v      v0, (a0), a2
+.endm
+
+func ff_vp8_idct_dc_add_rvv, zve32x
+        vsetivli      zero, 4, e8, mf4, ta, ma
+        vp8_idct_dc_add
+
+        ret
+endfunc

libavcodec/vp8dsp.c

@@ -742,6 +742,8 @@ av_cold void ff_vp8dsp_init(VP8DSPContext *dsp)
     ff_vp8dsp_init_aarch64(dsp);
 #elif ARCH_ARM
     ff_vp8dsp_init_arm(dsp);
+#elif ARCH_RISCV
+    ff_vp8dsp_init_riscv(dsp);
 #elif ARCH_X86
     ff_vp8dsp_init_x86(dsp);
 #elif ARCH_MIPS

libavcodec/vp8dsp.h

@@ -92,6 +92,7 @@ void ff_vp78dsp_init_x86(VP8DSPContext *c);
 void ff_vp8dsp_init(VP8DSPContext *c);
 void ff_vp8dsp_init_aarch64(VP8DSPContext *c);
 void ff_vp8dsp_init_arm(VP8DSPContext *c);
+void ff_vp8dsp_init_riscv(VP8DSPContext *c);
 void ff_vp8dsp_init_x86(VP8DSPContext *c);
 void ff_vp8dsp_init_mips(VP8DSPContext *c);
 void ff_vp8dsp_init_loongarch(VP8DSPContext *c);