lavc/blockdsp: R-V V clear_block

C908:
blockdsp.clear_block_c: 47.2
blockdsp.clear_block_rvv_i64: 28.5

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

libavcodec/blockdsp.c

@@ -69,6 +69,8 @@ av_cold void ff_blockdsp_init(BlockDSPContext *c)
     ff_blockdsp_init_arm(c);
 #elif ARCH_PPC
     ff_blockdsp_init_ppc(c);
+#elif ARCH_RISCV
+    ff_blockdsp_init_riscv(c);
 #elif ARCH_X86
     ff_blockdsp_init_x86(c);
 #elif ARCH_MIPS

libavcodec/blockdsp.h

@@ -41,6 +41,7 @@ void ff_blockdsp_init(BlockDSPContext *c);
 void ff_blockdsp_init_alpha(BlockDSPContext *c);
 void ff_blockdsp_init_arm(BlockDSPContext *c);
 void ff_blockdsp_init_ppc(BlockDSPContext *c);
+void ff_blockdsp_init_riscv(BlockDSPContext *c);
 void ff_blockdsp_init_x86(BlockDSPContext *c);
 void ff_blockdsp_init_mips(BlockDSPContext *c);
 

libavcodec/riscv/Makefile

@@ -10,6 +10,8 @@ RVV-OBJS-$(CONFIG_ALAC_DECODER) += riscv/alacdsp_rvv.o
 OBJS-$(CONFIG_AUDIODSP) += riscv/audiodsp_init.o
 RV-OBJS-$(CONFIG_AUDIODSP) += riscv/audiodsp_rvf.o
 RVV-OBJS-$(CONFIG_AUDIODSP) += riscv/audiodsp_rvv.o
+OBJS-$(CONFIG_BLOCKDSP) += riscv/blockdsp_init.o
+RVV-OBJS-$(CONFIG_BLOCKDSP) += riscv/blockdsp_rvv.o
 OBJS-$(CONFIG_BSWAPDSP) += riscv/bswapdsp_init.o
 RV-OBJS-$(CONFIG_BSWAPDSP) += riscv/bswapdsp_rvb.o
 RVV-OBJS-$(CONFIG_BSWAPDSP) += riscv/bswapdsp_rvv.o

libavcodec/riscv/blockdsp_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/blockdsp.h"
+
+void ff_clear_block_rvv(int16_t *block);
+
+av_cold void ff_blockdsp_init_riscv(BlockDSPContext *c)
+{
+#if HAVE_RVV
+    int flags = av_get_cpu_flags();
+
+    if (flags & AV_CPU_FLAG_RVV_I64 && ff_get_rv_vlenb() >= 16) {
+        c->clear_block = ff_clear_block_rvv;
+    }
+#endif
+}

libavcodec/riscv/blockdsp_rvv.S

@@ -0,0 +1,29 @@
+/*
+ * 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_clear_block_rvv, zve64x
+        vsetivli      zero, 16, e64, m8, ta, ma
+        vmv.v.i       v0, 0
+        vse64.v       v0, (a0)
+
+        ret
+endfunc