ffmpeg/libavutil/riscv/cpu.c
Rémi Denis-Courmont b6585eb04c lavu: add/use flag for RISC-V Zba extension
The code was blindly assuming that Zbb or V implied Zba. While the
earlier is practically always true, the later broke some QEMU setups,
as V was introduced earlier than Zba.
2023-07-19 19:29:35 +03:00

85 lines
2.3 KiB
C

/*
* 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 "libavutil/cpu.h"
#include "libavutil/cpu_internal.h"
#include "libavutil/log.h"
#include "config.h"
#if HAVE_GETAUXVAL
#include <sys/auxv.h>
#define HWCAP_RV(letter) (1ul << ((letter) - 'A'))
#endif
int ff_get_cpu_flags_riscv(void)
{
int ret = 0;
#if HAVE_GETAUXVAL
const unsigned long hwcap = getauxval(AT_HWCAP);
if (hwcap & HWCAP_RV('I'))
ret |= AV_CPU_FLAG_RVI;
if (hwcap & HWCAP_RV('F'))
ret |= AV_CPU_FLAG_RVF;
if (hwcap & HWCAP_RV('D'))
ret |= AV_CPU_FLAG_RVD;
if (hwcap & HWCAP_RV('B'))
ret |= AV_CPU_FLAG_RVB_ADDR | AV_CPU_FLAG_RVB_BASIC;
/* The V extension implies all Zve* functional subsets */
if (hwcap & HWCAP_RV('V'))
ret |= AV_CPU_FLAG_RVV_I32 | AV_CPU_FLAG_RVV_I64
| AV_CPU_FLAG_RVV_F32 | AV_CPU_FLAG_RVV_F64;
#endif
#ifdef __riscv_i
ret |= AV_CPU_FLAG_RVI;
#endif
#if defined (__riscv_flen) && (__riscv_flen >= 32)
ret |= AV_CPU_FLAG_RVF;
#if (__riscv_flen >= 64)
ret |= AV_CPU_FLAG_RVD;
#endif
#endif
#ifdef __riscv_zba
ret |= AV_CPU_FLAG_RVB_ADDR;
#endif
#ifdef __riscv_zbb
ret |= AV_CPU_FLAG_RVB_BASIC;
#endif
/* If RV-V is enabled statically at compile-time, check the details. */
#ifdef __riscv_vectors
ret |= AV_CPU_FLAG_RVV_I32;
#if __riscv_v_elen >= 64
ret |= AV_CPU_FLAG_RVV_I64;
#endif
#if __riscv_v_elen_fp >= 32
ret |= AV_CPU_FLAG_RVV_F32;
#if __riscv_v_elen_fp >= 64
ret |= AV_CPU_FLAG_RVV_F64;
#endif
#endif
#endif
return ret;
}