mirror of
https://git.ffmpeg.org/ffmpeg.git
synced 2024-12-15 19:55:08 +00:00
bb270c0896
Originally committed as revision 4764 to svn://svn.ffmpeg.org/ffmpeg/trunk
156 lines
3.0 KiB
C
156 lines
3.0 KiB
C
/**
|
|
* @file bswap.h
|
|
* byte swap.
|
|
*/
|
|
|
|
#ifndef __BSWAP_H__
|
|
#define __BSWAP_H__
|
|
|
|
#ifdef HAVE_BYTESWAP_H
|
|
#include <byteswap.h>
|
|
#else
|
|
|
|
#ifdef ARCH_X86_64
|
|
# define LEGACY_REGS "=Q"
|
|
#else
|
|
# define LEGACY_REGS "=q"
|
|
#endif
|
|
|
|
#if defined(ARCH_X86) || defined(ARCH_X86_64)
|
|
static always_inline uint16_t bswap_16(uint16_t x)
|
|
{
|
|
__asm("rorw $8, %0" :
|
|
LEGACY_REGS (x) :
|
|
"0" (x));
|
|
return x;
|
|
}
|
|
|
|
static always_inline uint32_t bswap_32(uint32_t x)
|
|
{
|
|
#if __CPU__ > 386
|
|
__asm("bswap %0":
|
|
"=r" (x) :
|
|
#else
|
|
__asm("xchgb %b0,%h0\n"
|
|
" rorl $16,%0\n"
|
|
" xchgb %b0,%h0":
|
|
LEGACY_REGS (x) :
|
|
#endif
|
|
"0" (x));
|
|
return x;
|
|
}
|
|
|
|
static inline uint64_t bswap_64(uint64_t x)
|
|
{
|
|
#ifdef ARCH_X86_64
|
|
__asm("bswap %0":
|
|
"=r" (x) :
|
|
"0" (x));
|
|
return x;
|
|
#else
|
|
union {
|
|
uint64_t ll;
|
|
struct {
|
|
uint32_t l,h;
|
|
} l;
|
|
} r;
|
|
r.l.l = bswap_32 (x);
|
|
r.l.h = bswap_32 (x>>32);
|
|
return r.ll;
|
|
#endif
|
|
}
|
|
|
|
#elif defined(ARCH_SH4)
|
|
|
|
static always_inline uint16_t bswap_16(uint16_t x) {
|
|
__asm__("swap.b %0,%0":"=r"(x):"0"(x));
|
|
return x;
|
|
}
|
|
|
|
static always_inline uint32_t bswap_32(uint32_t x) {
|
|
__asm__(
|
|
"swap.b %0,%0\n"
|
|
"swap.w %0,%0\n"
|
|
"swap.b %0,%0\n"
|
|
:"=r"(x):"0"(x));
|
|
return x;
|
|
}
|
|
|
|
static inline uint64_t bswap_64(uint64_t x)
|
|
{
|
|
union {
|
|
uint64_t ll;
|
|
struct {
|
|
uint32_t l,h;
|
|
} l;
|
|
} r;
|
|
r.l.l = bswap_32 (x);
|
|
r.l.h = bswap_32 (x>>32);
|
|
return r.ll;
|
|
}
|
|
#else
|
|
|
|
static always_inline uint16_t bswap_16(uint16_t x){
|
|
return (x>>8) | (x<<8);
|
|
}
|
|
|
|
#ifdef ARCH_ARM
|
|
static always_inline uint32_t bswap_32(uint32_t x){
|
|
uint32_t t;
|
|
__asm__ (
|
|
"eor %1, %0, %0, ror #16 \n\t"
|
|
"bic %1, %1, #0xFF0000 \n\t"
|
|
"mov %0, %0, ror #8 \n\t"
|
|
"eor %0, %0, %1, lsr #8 \n\t"
|
|
: "+r"(x), "+r"(t));
|
|
return x;
|
|
}
|
|
#else
|
|
static always_inline uint32_t bswap_32(uint32_t x){
|
|
x= ((x<<8)&0xFF00FF00) | ((x>>8)&0x00FF00FF);
|
|
return (x>>16) | (x<<16);
|
|
}
|
|
#endif
|
|
|
|
static inline uint64_t bswap_64(uint64_t x)
|
|
{
|
|
#if 0
|
|
x= ((x<< 8)&0xFF00FF00FF00FF00ULL) | ((x>> 8)&0x00FF00FF00FF00FFULL);
|
|
x= ((x<<16)&0xFFFF0000FFFF0000ULL) | ((x>>16)&0x0000FFFF0000FFFFULL);
|
|
return (x>>32) | (x<<32);
|
|
#else
|
|
union {
|
|
uint64_t ll;
|
|
uint32_t l[2];
|
|
} w, r;
|
|
w.ll = x;
|
|
r.l[0] = bswap_32 (w.l[1]);
|
|
r.l[1] = bswap_32 (w.l[0]);
|
|
return r.ll;
|
|
#endif
|
|
}
|
|
#endif /* !ARCH_X86 */
|
|
|
|
#endif /* !HAVE_BYTESWAP_H */
|
|
|
|
// be2me ... BigEndian to MachineEndian
|
|
// le2me ... LittleEndian to MachineEndian
|
|
|
|
#ifdef WORDS_BIGENDIAN
|
|
#define be2me_16(x) (x)
|
|
#define be2me_32(x) (x)
|
|
#define be2me_64(x) (x)
|
|
#define le2me_16(x) bswap_16(x)
|
|
#define le2me_32(x) bswap_32(x)
|
|
#define le2me_64(x) bswap_64(x)
|
|
#else
|
|
#define be2me_16(x) bswap_16(x)
|
|
#define be2me_32(x) bswap_32(x)
|
|
#define be2me_64(x) bswap_64(x)
|
|
#define le2me_16(x) (x)
|
|
#define le2me_32(x) (x)
|
|
#define le2me_64(x) (x)
|
|
#endif
|
|
|
|
#endif /* __BSWAP_H__ */
|