[FFmpeg-devel] [PATCH 22/26] lavc/fmtconvert: RISC-V V int32_to_float_fmul_scalar

[Andreas Rheinhardt]

remi at remlab.net:
> From: Rémi Denis-Courmont <remi at remlab.net>
> 
> ---
>  libavcodec/fmtconvert.c            |  2 ++
>  libavcodec/fmtconvert.h            |  1 +
>  libavcodec/riscv/Makefile          |  2 ++
>  libavcodec/riscv/fmtconvert_init.c | 41 ++++++++++++++++++++++++++++++
>  libavcodec/riscv/fmtconvert_rvv.S  | 40 +++++++++++++++++++++++++++++
>  5 files changed, 86 insertions(+)
>  create mode 100644 libavcodec/riscv/fmtconvert_init.c
>  create mode 100644 libavcodec/riscv/fmtconvert_rvv.S
> 
> diff --git a/libavcodec/fmtconvert.c b/libavcodec/fmtconvert.c
> index 00f55f8f1e..8dcef82ee3 100644
> --- a/libavcodec/fmtconvert.c
> +++ b/libavcodec/fmtconvert.c
> @@ -53,6 +53,8 @@ av_cold void ff_fmt_convert_init(FmtConvertContext *c, AVCodecContext *avctx)
>      ff_fmt_convert_init_arm(c, avctx);
>  #elif ARCH_PPC
>      ff_fmt_convert_init_ppc(c, avctx);
> +#elif ARCH_RISCV
> +    ff_fmt_convert_init_riscv(c, avctx);
>  #elif ARCH_X86
>      ff_fmt_convert_init_x86(c, avctx);
>  #endif
> diff --git a/libavcodec/fmtconvert.h b/libavcodec/fmtconvert.h
> index b2df7a9629..ca51d0861a 100644
> --- a/libavcodec/fmtconvert.h
> +++ b/libavcodec/fmtconvert.h
> @@ -61,6 +61,7 @@ void ff_fmt_convert_init(FmtConvertContext *c, AVCodecContext *avctx);
>  void ff_fmt_convert_init_aarch64(FmtConvertContext *c, AVCodecContext *avctx);
>  void ff_fmt_convert_init_arm(FmtConvertContext *c, AVCodecContext *avctx);
>  void ff_fmt_convert_init_ppc(FmtConvertContext *c, AVCodecContext *avctx);
> +void ff_fmt_convert_init_riscv(FmtConvertContext *c, AVCodecContext *avctx);
>  void ff_fmt_convert_init_x86(FmtConvertContext *c, AVCodecContext *avctx);
>  void ff_fmt_convert_init_mips(FmtConvertContext *c);
>  
> diff --git a/libavcodec/riscv/Makefile b/libavcodec/riscv/Makefile
> index 99541b075e..682174e875 100644
> --- a/libavcodec/riscv/Makefile
> +++ b/libavcodec/riscv/Makefile
> @@ -1,5 +1,7 @@
>  OBJS-$(CONFIG_AUDIODSP) += riscv/audiodsp_init.o \
>                             riscv/audiodsp_rvf.o
>  RVV-OBJS-$(CONFIG_AUDIODSP) += riscv/audiodsp_rvv.o
> +OBJS-$(CONFIG_FMTCONVERT) += riscv/fmtconvert_init.o
> +RVV-OBJS-$(CONFIG_FMTCONVERT) += riscv/fmtconvert_rvv.o
>  OBJS-$(CONFIG_PIXBLOCKDSP) += riscv/pixblockdsp_init.o \
>                                riscv/pixblockdsp_rvi.o
> diff --git a/libavcodec/riscv/fmtconvert_init.c b/libavcodec/riscv/fmtconvert_init.c
> new file mode 100644
> index 0000000000..aa7d44ff5a
> --- /dev/null
> +++ b/libavcodec/riscv/fmtconvert_init.c
> @@ -0,0 +1,41 @@
> +/*
> + * Copyright © 2022 Rémi Denis-Courmont.
> + *
> + * 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 "config.h"
> +#include "libavutil/attributes.h"
> +#include "libavutil/cpu.h"
> +#include "libavcodec/avcodec.h"
> +#include "libavcodec/fmtconvert.h"
> +
> +void ff_int32_to_float_fmul_scalar_rvv(float *dst, const int32_t *src,
> +                                       float mul, int len);
> +
> +av_cold void ff_fmt_convert_init_riscv(FmtConvertContext *c,
> +                                       AVCodecContext *avctx)
> +{
> +#ifdef HAVE_RVV
> +    int flags = av_get_cpu_flags();
> +
> +    if (flags & AV_CPU_FLAG_RV_ZVE32F)
> +        c->int32_to_float_fmul_scalar = ff_int32_to_float_fmul_scalar_rvv;

If you added {} in this patch, you would not need to rewrite the if-line
in the next patch.

> +#endif
> +}
> diff --git a/libavcodec/riscv/fmtconvert_rvv.S b/libavcodec/riscv/fmtconvert_rvv.S
> new file mode 100644
> index 0000000000..c19b77e38a
> --- /dev/null
> +++ b/libavcodec/riscv/fmtconvert_rvv.S
> @@ -0,0 +1,40 @@
> +/*
> + * Copyright © 2022 Rémi Denis-Courmont.
> + *
> + * 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/riscv/asm.S"
> +
> +func ff_int32_to_float_fmul_scalar_rvv, zve32f
> +NOHWF   fmv.w.x     fa0, a2
> +NOHWF   mv          a2, a3
> +1:
> +        vsetvli     t0, a2, e32, m1, ta, ma
> +        vle32.v     v24, (a1)
> +        slli        t1, t0, 2
> +        vfcvt.f.x.v v24, v24
> +        sub         a2, a2, t0
> +        vfmul.vf    v24, v24, fa0
> +        add         a1, a1, t1
> +        vse32.v     v24, (a0)
> +        add         a0, a0, t1
> +        bnez        a2, 1b
> +
> +        ret
> +endfunc

Notice that there will be a slight conflict with
https://ffmpeg.org/pipermail/ffmpeg-devel/2022-September/301710.html;
but it is trivial to fix. Just don't forget to remove the avcodec.h
inclusion.

- Andreas