lavc/takdsp: R-V V decorrelate_ls

C908:
decorrelate_ls_c: 69.7
decorrelate_ls_rvv_i32: 27.2

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

libavcodec/riscv/Makefile

@@ -42,6 +42,8 @@ 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-$(CONFIG_TAK_DECODER) += riscv/takdsp_init.o
+RVV-OBJS-$(CONFIG_TAK_DECODER) += riscv/takdsp_rvv.o
 OBJS-$(CONFIG_UTVIDEO_DECODER) += riscv/utvideodsp_init.o
 RVV-OBJS-$(CONFIG_UTVIDEO_DECODER) += riscv/utvideodsp_rvv.o
 OBJS-$(CONFIG_VC1DSP) += riscv/vc1dsp_init.o

libavcodec/riscv/takdsp_init.c

@@ -0,0 +1,39 @@
+/*
+ * 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 <stdint.h>
+
+#include "libavutil/attributes.h"
+#include "libavutil/cpu.h"
+#include "libavutil/riscv/cpu.h"
+#include "libavcodec/takdsp.h"
+
+void ff_decorrelate_ls_rvv(int32_t *p1, int32_t *p2, int length);
+
+av_cold void ff_takdsp_init_riscv(TAKDSPContext *dsp)
+{
+#if HAVE_RVV
+    int flags = av_get_cpu_flags();
+
+    if ((flags & AV_CPU_FLAG_RVV_I32) && (flags & AV_CPU_FLAG_RVB_ADDR)) {
+        dsp->decorrelate_ls = ff_decorrelate_ls_rvv;
+    }
+#endif
+}

libavcodec/riscv/takdsp_rvv.S

@@ -0,0 +1,35 @@
+/*
+ * 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_decorrelate_ls_rvv, zve32x
+1:
+        vsetvli  t0, a2, e32, m8, ta, ma
+        sub      a2, a2, t0
+        vle32.v  v0, (a0)
+        sh2add   a0, t0, a0
+        vle32.v  v8, (a1)
+        vadd.vv  v16, v0, v8
+        vse32.v  v16, (a1)
+        sh2add   a1, t0, a1
+        bnez a2, 1b
+        ret
+endfunc

libavcodec/takdsp.c

@@ -77,7 +77,9 @@ av_cold void ff_takdsp_init(TAKDSPContext *c)
     c->decorrelate_sm = decorrelate_sm;
     c->decorrelate_sf = decorrelate_sf;
 
-#if ARCH_X86
+#if ARCH_RISCV
+    ff_takdsp_init_riscv(c);
+#elif ARCH_X86
     ff_takdsp_init_x86(c);
 #endif
 }

libavcodec/takdsp.h

@@ -29,6 +29,7 @@ typedef struct TAKDSPContext {
 } TAKDSPContext;
 
 void ff_takdsp_init(TAKDSPContext *c);
+void ff_takdsp_init_riscv(TAKDSPContext *c);
 void ff_takdsp_init_x86(TAKDSPContext *c);
 
 #endif /* AVCODEC_TAKDSP_H */