SDL_endian.h
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/*
Simple DirectMedia Layer
Copyright (C) 1997-2016 Sam Lantinga <slouken@libsdl.org>
This software is provided 'as-is', without any express or implied
warranty. In no event will the authors be held liable for any damages
arising from the use of this software.
Permission is granted to anyone to use this software for any purpose,
including commercial applications, and to alter it and redistribute it
freely, subject to the following restrictions:
1. The origin of this software must not be misrepresented; you must not
claim that you wrote the original software. If you use this software
in a product, an acknowledgment in the product documentation would be
appreciated but is not required.
2. Altered source versions must be plainly marked as such, and must not be
misrepresented as being the original software.
3. This notice may not be removed or altered from any source distribution.
*/
/**
* \file SDL_endian.h
*
* Functions for reading and writing endian-specific values
*/
#ifndef _SDL_endian_h
#define _SDL_endian_h
#include "SDL_stdinc.h"
/**
* \name The two types of endianness
*/
/* @{ */
#define SDL_LIL_ENDIAN 1234
#define SDL_BIG_ENDIAN 4321
/* @} */
#ifndef SDL_BYTEORDER /* Not defined in SDL_config.h? */
#ifdef __linux__
#include <endian.h>
#define SDL_BYTEORDER __BYTE_ORDER
#else /* __linux__ */
#if defined(__hppa__) || \
defined(__m68k__) || defined(mc68000) || defined(_M_M68K) || \
(defined(__MIPS__) && defined(__MISPEB__)) || \
defined(__ppc__) || defined(__POWERPC__) || defined(_M_PPC) || \
defined(__sparc__)
#define SDL_BYTEORDER SDL_BIG_ENDIAN
#else
#define SDL_BYTEORDER SDL_LIL_ENDIAN
#endif
#endif /* __linux__ */
#endif /* !SDL_BYTEORDER */
#include "begin_code.h"
/* Set up for C function definitions, even when using C++ */
#ifdef __cplusplus
extern "C" {
#endif
/**
* \file SDL_endian.h
*/
#if defined(__GNUC__) && defined(__i386__) && \
!(__GNUC__ == 2 && __GNUC_MINOR__ == 95 /* broken gcc version */)
SDL_FORCE_INLINE Uint16
SDL_Swap16(Uint16 x)
{
__asm__("xchgb %b0,%h0": "=q"(x):"0"(x));
return x;
}
#elif defined(__GNUC__) && defined(__x86_64__)
SDL_FORCE_INLINE Uint16
SDL_Swap16(Uint16 x)
{
__asm__("xchgb %b0,%h0": "=Q"(x):"0"(x));
return x;
}
#elif defined(__GNUC__) && (defined(__powerpc__) || defined(__ppc__))
SDL_FORCE_INLINE Uint16
SDL_Swap16(Uint16 x)
{
int result;
__asm__("rlwimi %0,%2,8,16,23": "=&r"(result):"0"(x >> 8), "r"(x));
return (Uint16)result;
}
#elif defined(__GNUC__) && (defined(__M68000__) || defined(__M68020__)) && !defined(__mcoldfire__)
SDL_FORCE_INLINE Uint16
SDL_Swap16(Uint16 x)
{
__asm__("rorw #8,%0": "=d"(x): "0"(x):"cc");
return x;
}
#else
SDL_FORCE_INLINE Uint16
SDL_Swap16(Uint16 x)
{
return SDL_static_cast(Uint16, ((x << 8) | (x >> 8)));
}
#endif
#if defined(__GNUC__) && defined(__i386__)
SDL_FORCE_INLINE Uint32
SDL_Swap32(Uint32 x)
{
__asm__("bswap %0": "=r"(x):"0"(x));
return x;
}
#elif defined(__GNUC__) && defined(__x86_64__)
SDL_FORCE_INLINE Uint32
SDL_Swap32(Uint32 x)
{
__asm__("bswapl %0": "=r"(x):"0"(x));
return x;
}
#elif defined(__GNUC__) && (defined(__powerpc__) || defined(__ppc__))
SDL_FORCE_INLINE Uint32
SDL_Swap32(Uint32 x)
{
Uint32 result;
__asm__("rlwimi %0,%2,24,16,23": "=&r"(result):"0"(x >> 24), "r"(x));
__asm__("rlwimi %0,%2,8,8,15": "=&r"(result):"0"(result), "r"(x));
__asm__("rlwimi %0,%2,24,0,7": "=&r"(result):"0"(result), "r"(x));
return result;
}
#elif defined(__GNUC__) && (defined(__M68000__) || defined(__M68020__)) && !defined(__mcoldfire__)
SDL_FORCE_INLINE Uint32
SDL_Swap32(Uint32 x)
{
__asm__("rorw #8,%0\n\tswap %0\n\trorw #8,%0": "=d"(x): "0"(x):"cc");
return x;
}
#else
SDL_FORCE_INLINE Uint32
SDL_Swap32(Uint32 x)
{
return SDL_static_cast(Uint32, ((x << 24) | ((x << 8) & 0x00FF0000) |
((x >> 8) & 0x0000FF00) | (x >> 24)));
}
#endif
#if defined(__GNUC__) && defined(__i386__)
SDL_FORCE_INLINE Uint64
SDL_Swap64(Uint64 x)
{
union
{
struct
{
Uint32 a, b;
} s;
Uint64 u;
} v;
v.u = x;
__asm__("bswapl %0 ; bswapl %1 ; xchgl %0,%1": "=r"(v.s.a), "=r"(v.s.b):"0"(v.s.a),
"1"(v.s.
b));
return v.u;
}
#elif defined(__GNUC__) && defined(__x86_64__)
SDL_FORCE_INLINE Uint64
SDL_Swap64(Uint64 x)
{
__asm__("bswapq %0": "=r"(x):"0"(x));
return x;
}
#else
SDL_FORCE_INLINE Uint64
SDL_Swap64(Uint64 x)
{
Uint32 hi, lo;
/* Separate into high and low 32-bit values and swap them */
lo = SDL_static_cast(Uint32, x & 0xFFFFFFFF);
x >>= 32;
hi = SDL_static_cast(Uint32, x & 0xFFFFFFFF);
x = SDL_Swap32(lo);
x <<= 32;
x |= SDL_Swap32(hi);
return (x);
}
#endif
SDL_FORCE_INLINE float
SDL_SwapFloat(float x)
{
union
{
float f;
Uint32 ui32;
} swapper;
swapper.f = x;
swapper.ui32 = SDL_Swap32(swapper.ui32);
return swapper.f;
}
/**
* \name Swap to native
* Byteswap item from the specified endianness to the native endianness.
*/
/* @{ */
#if SDL_BYTEORDER == SDL_LIL_ENDIAN
#define SDL_SwapLE16(X) (X)
#define SDL_SwapLE32(X) (X)
#define SDL_SwapLE64(X) (X)
#define SDL_SwapFloatLE(X) (X)
#define SDL_SwapBE16(X) SDL_Swap16(X)
#define SDL_SwapBE32(X) SDL_Swap32(X)
#define SDL_SwapBE64(X) SDL_Swap64(X)
#define SDL_SwapFloatBE(X) SDL_SwapFloat(X)
#else
#define SDL_SwapLE16(X) SDL_Swap16(X)
#define SDL_SwapLE32(X) SDL_Swap32(X)
#define SDL_SwapLE64(X) SDL_Swap64(X)
#define SDL_SwapFloatLE(X) SDL_SwapFloat(X)
#define SDL_SwapBE16(X) (X)
#define SDL_SwapBE32(X) (X)
#define SDL_SwapBE64(X) (X)
#define SDL_SwapFloatBE(X) (X)
#endif
/* @} *//* Swap to native */
/* Ends C function definitions when using C++ */
#ifdef __cplusplus
}
#endif
#include "close_code.h"
#endif /* _SDL_endian_h */
/* vi: set ts=4 sw=4 expandtab: */
result
GLuint64EXT * result
Definition: SDL_opengl_glext.h:9432
s
GLdouble s
Definition: SDL_opengl.h:2056
Uint32
uint32_t Uint32
An unsigned 32-bit integer type.
Definition: SDL_stdinc.h:157
x
GLint GLint GLint GLint GLint x
Definition: SDL_opengl.h:1567
f
GLfloat f
Definition: SDL_opengl_glext.h:1870
begin_code.h
SDL_FORCE_INLINE
#define SDL_FORCE_INLINE
Definition: begin_code.h:133
Uint64
uint64_t Uint64
An unsigned 64-bit integer type.
Definition: SDL_stdinc.h:166
SDL_Swap32
SDL_FORCE_INLINE Uint32 SDL_Swap32(Uint32 x)
Definition: SDL_endian.h:141
v
const GLdouble * v
Definition: SDL_opengl.h:2057
close_code.h
SDL_static_cast
#define SDL_static_cast(type, expression)
Definition: SDL_stdinc.h:109
SDL_Swap16
SDL_FORCE_INLINE Uint16 SDL_Swap16(Uint16 x)
Definition: SDL_endian.h:101
SDL_stdinc.h
SDL_Swap64
SDL_FORCE_INLINE Uint64 SDL_Swap64(Uint64 x)
Definition: SDL_endian.h:175
Uint16
uint16_t Uint16
An unsigned 16-bit integer type.
Definition: SDL_stdinc.h:147
a
GLboolean GLboolean GLboolean GLboolean a
Definition: SDL_opengl_glext.h:1109
b
GLboolean GLboolean GLboolean b
Definition: SDL_opengl_glext.h:1109
SDL_SwapFloat
SDL_FORCE_INLINE float SDL_SwapFloat(float x)
Definition: SDL_endian.h:192