cpu.h

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/*
 * 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
 */
 
#ifndef AVUTIL_RISCV_CPU_H
#define AVUTIL_RISCV_CPU_H
 
#include "config.h"
#include <stddef.h>
#include "libavutil/cpu.h"
 
#if HAVE_RVV
/**
 * Returns the vector size in bytes (always a power of two and at least 4).
 * This is undefined behaviour if vectors are not implemented.
 */
static inline size_t ff_get_rv_vlenb(void)
{
    size_t vlenb;
 
    __asm__ (
        ".option push\n"
        ".option arch, +v\n"
        "    csrr %0, vlenb\n"
        ".option pop\n" : "=r" (vlenb));
    return vlenb;
}
#endif
#endif