lavc/rv34dsp: R-V V rv34_inv_transform_dc

C908:
rv34_inv_transform_dc_c: 35.5
rv34_inv_transform_dc_rvv_i32: 27.0

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

libavcodec/riscv/Makefile

@@ -44,6 +44,8 @@ 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-$(CONFIG_RV34DSP) += riscv/rv34dsp_init.o
+RVV-OBJS-$(CONFIG_RV34DSP) += riscv/rv34dsp_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

libavcodec/riscv/rv34dsp_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/rv34dsp.h"
+
+void ff_rv34_inv_transform_dc_rvv(int16_t *block);
+
+av_cold void ff_rv34dsp_init_riscv(RV34DSPContext *c)
+{
+#if HAVE_RVV
+    int flags = av_get_cpu_flags();
+
+    if (flags & AV_CPU_FLAG_RVV_I32 && ff_get_rv_vlenb() >= 16) {
+        c->rv34_inv_transform_dc = ff_rv34_inv_transform_dc_rvv;
+    }
+#endif
+}

libavcodec/riscv/rv34dsp_rvv.S

@@ -0,0 +1,33 @@
+/*
+ * 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"
+
+func ff_rv34_inv_transform_dc_rvv, zve32x
+        lh            t1, 0(a0)
+        li            t0, 13 * 13 * 3
+        mul           t2, t0, t1
+        srai          t2, t2, 11
+        vsetivli      zero, 16, e16, m2, ta, ma
+        vmv.v.x       v8, t2
+        vse16.v       v8, (a0)
+
+        ret
+endfunc

libavcodec/rv34dsp.c

@@ -138,6 +138,8 @@ av_cold void ff_rv34dsp_init(RV34DSPContext *c)
 
 #if ARCH_ARM
     ff_rv34dsp_init_arm(c);
+#elif ARCH_RISCV
+    ff_rv34dsp_init_riscv(c);
 #elif ARCH_X86
     ff_rv34dsp_init_x86(c);
 #endif

libavcodec/rv34dsp.h

@@ -79,6 +79,7 @@ void ff_rv34dsp_init(RV34DSPContext *c);
 void ff_rv40dsp_init(RV34DSPContext *c);
 
 void ff_rv34dsp_init_arm(RV34DSPContext *c);
+void ff_rv34dsp_init_riscv(RV34DSPContext *c);
 void ff_rv34dsp_init_x86(RV34DSPContext *c);
 
 void ff_rv40dsp_init_aarch64(RV34DSPContext *c);