ffmpeg/FFmpeg
1
0
Fork 0
mirror of https://git.ffmpeg.org/ffmpeg.git synced 2024-09-16 19:43:37 +00:00
Code Issues Packages Projects Releases Wiki Activity

lavu/bswap: remove some inline assembler

Browse Source 
C code or compiler built-ins are preferable over inline assembler for
byte-swaps as it allows for better optimisations (e.g. instruction
scheduling) which would otherwise be impossible.

As with f64c2e710f for x86 and Arm,
this removes the inline assembler on GCC (and Clang) since we now
require recent enough compiler versions. This indeed seems to work on
AArch64, SuperH and, if Zbb is enabled, RISC-V. (AVR32 was not tested
since it has no known working compilers at this time.)
This commit is contained in:
Rémi Denis-Courmont 2024-06-07 21:08:21 +03:00
parent 0231097d1b
commit c5f69719bc
4 changed files with 1 additions and 155 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

56
libavutil/aarch64/bswap.h
View File

@ -1,56 +0,0 @@
/*
* 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_AARCH64_BSWAP_H
#define AVUTIL_AARCH64_BSWAP_H
#include <stdint.h>
#include "config.h"
#include "libavutil/attributes.h"
#if HAVE_INLINE_ASM
#define av_bswap16 av_bswap16
static av_always_inline av_const unsigned av_bswap16(unsigned x)
{
unsigned y;
__asm__("rev16 %w0, %w1" : "=r"(y) : "r"(x));
return y;
}
#define av_bswap32 av_bswap32
static av_always_inline av_const uint32_t av_bswap32(uint32_t x)
{
uint32_t y;
__asm__("rev %w0, %w1" : "=r"(y) : "r"(x));
return y;
}
#define av_bswap64 av_bswap64
static av_always_inline av_const uint64_t av_bswap64(uint64_t x)
{
uint64_t y;
__asm__("rev %0, %1" : "=r"(y) : "r"(x));
return y;
}
#endif /* HAVE_INLINE_ASM */
#endif /* AVUTIL_AARCH64_BSWAP_H */

44
libavutil/avr32/bswap.h
View File

@ -1,44 +0,0 @@
/*
* 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_AVR32_BSWAP_H
#define AVUTIL_AVR32_BSWAP_H
#include <stdint.h>
#include "config.h"
#include "libavutil/attributes.h"
#if HAVE_INLINE_ASM
#define av_bswap16 av_bswap16
static av_always_inline av_const uint16_t av_bswap16(uint16_t x)
{
__asm__ ("swap.bh %0" : "+r"(x));
return x;
}
#define av_bswap32 av_bswap32
static av_always_inline av_const uint32_t av_bswap32(uint32_t x)
{
__asm__ ("swap.b %0" : "+r"(x));
return x;
}
#endif /* HAVE_INLINE_ASM */
#endif /* AVUTIL_AVR32_BSWAP_H */

8
libavutil/bswap.h
View File

@ -34,16 +34,10 @@
#include "config.h"
#if ARCH_AARCH64
# include "aarch64/bswap.h"
#elif ARCH_ARM
#if ARCH_ARM
# include "arm/bswap.h"
#elif ARCH_AVR32
# include "avr32/bswap.h"
#elif ARCH_RISCV
# include "riscv/bswap.h"
#elif ARCH_SH4
# include "sh4/bswap.h"
#elif ARCH_X86
# include "x86/bswap.h"
#endif

48
libavutil/sh4/bswap.h
View File

@ -1,48 +0,0 @@
/*
* 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
*/
/**
* @file
* byte swapping routines
*/
#ifndef AVUTIL_SH4_BSWAP_H
#define AVUTIL_SH4_BSWAP_H
#include <stdint.h>
#include "config.h"
#include "libavutil/attributes.h"
#define av_bswap16 av_bswap16
static av_always_inline av_const uint16_t av_bswap16(uint16_t x)
{
__asm__("swap.b %0,%0" : "+r"(x));
return x;
}
#define av_bswap32 av_bswap32
static av_always_inline av_const uint32_t av_bswap32(uint32_t x)
{
__asm__("swap.b %0,%0\n"
"swap.w %0,%0\n"
"swap.b %0,%0\n"
: "+r"(x));
return x;
}
#endif /* AVUTIL_SH4_BSWAP_H */