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+/*
+  Simple DirectMedia Layer
+  Copyright (C) 1997-2022 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"
+
+#if defined(_MSC_VER) && (_MSC_VER >= 1400)
+/* As of Clang 11, '_m_prefetchw' is conflicting with the winnt.h's version,
+   so we define the needed '_m_prefetch' here as a pseudo-header, until the issue is fixed. */
+#ifdef __clang__
+#ifndef __PRFCHWINTRIN_H
+#define __PRFCHWINTRIN_H
+static __inline__ void __attribute__((__always_inline__, __nodebug__))
+_m_prefetch(void *__P)
+{
+  __builtin_prefetch (__P, 0, 3 /* _MM_HINT_T0 */);
+}
+#endif /* __PRFCHWINTRIN_H */
+#endif /* __clang__ */
+
+#include <intrin.h>
+#endif
+
+/**
+ *  \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
+#elif defined(__OpenBSD__)
+#include <endian.h>
+#define SDL_BYTEORDER  BYTE_ORDER
+#elif defined(__FreeBSD__) || defined(__NetBSD__)
+#include <sys/endian.h>
+#define SDL_BYTEORDER  BYTE_ORDER
+#else
+#if defined(__hppa__) || \
+    defined(__m68k__) || defined(mc68000) || defined(_M_M68K) || \
+    (defined(__MIPS__) && defined(__MIPSEB__)) || \
+    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
+ */
+
+/* various modern compilers may have builtin swap */
+#if defined(__GNUC__) || defined(__clang__)
+#   define HAS_BUILTIN_BSWAP16 (_SDL_HAS_BUILTIN(__builtin_bswap16)) || \
+        (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 8))
+#   define HAS_BUILTIN_BSWAP32 (_SDL_HAS_BUILTIN(__builtin_bswap32)) || \
+        (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 3))
+#   define HAS_BUILTIN_BSWAP64 (_SDL_HAS_BUILTIN(__builtin_bswap64)) || \
+        (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 3))
+
+    /* this one is broken */
+#   define HAS_BROKEN_BSWAP (__GNUC__ == 2 && __GNUC_MINOR__ <= 95)
+#else
+#   define HAS_BUILTIN_BSWAP16 0
+#   define HAS_BUILTIN_BSWAP32 0
+#   define HAS_BUILTIN_BSWAP64 0
+#   define HAS_BROKEN_BSWAP 0
+#endif
+
+#if HAS_BUILTIN_BSWAP16
+#define SDL_Swap16(x) __builtin_bswap16(x)
+#elif defined(_MSC_VER) && (_MSC_VER >= 1400)
+#pragma intrinsic(_byteswap_ushort)
+#define SDL_Swap16(x) _byteswap_ushort(x)
+#elif defined(__i386__) && !HAS_BROKEN_BSWAP
+SDL_FORCE_INLINE Uint16
+SDL_Swap16(Uint16 x)
+{
+  __asm__("xchgb %b0,%h0": "=q"(x):"0"(x));
+    return x;
+}
+#elif defined(__x86_64__)
+SDL_FORCE_INLINE Uint16
+SDL_Swap16(Uint16 x)
+{
+  __asm__("xchgb %b0,%h0": "=Q"(x):"0"(x));
+    return x;
+}
+#elif (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(__m68k__) && !defined(__mcoldfire__))
+SDL_FORCE_INLINE Uint16
+SDL_Swap16(Uint16 x)
+{
+  __asm__("rorw #8,%0": "=d"(x): "0"(x):"cc");
+    return x;
+}
+#elif defined(__WATCOMC__) && defined(__386__)
+extern __inline Uint16 SDL_Swap16(Uint16);
+#pragma aux SDL_Swap16 = \
+  "xchg al, ah" \
+  parm   [ax]   \
+  modify [ax];
+#else
+SDL_FORCE_INLINE Uint16
+SDL_Swap16(Uint16 x)
+{
+    return SDL_static_cast(Uint16, ((x << 8) | (x >> 8)));
+}
+#endif
+
+#if HAS_BUILTIN_BSWAP32
+#define SDL_Swap32(x) __builtin_bswap32(x)
+#elif defined(_MSC_VER) && (_MSC_VER >= 1400)
+#pragma intrinsic(_byteswap_ulong)
+#define SDL_Swap32(x) _byteswap_ulong(x)
+#elif defined(__i386__) && !HAS_BROKEN_BSWAP
+SDL_FORCE_INLINE Uint32
+SDL_Swap32(Uint32 x)
+{
+  __asm__("bswap %0": "=r"(x):"0"(x));
+    return x;
+}
+#elif defined(__x86_64__)
+SDL_FORCE_INLINE Uint32
+SDL_Swap32(Uint32 x)
+{
+  __asm__("bswapl %0": "=r"(x):"0"(x));
+    return x;
+}
+#elif (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(__m68k__) && !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;
+}
+#elif defined(__WATCOMC__) && defined(__386__)
+extern __inline Uint32 SDL_Swap32(Uint32);
+#pragma aux SDL_Swap32 = \
+  "bswap eax"  \
+  parm   [eax] \
+  modify [eax];
+#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 HAS_BUILTIN_BSWAP64
+#define SDL_Swap64(x) __builtin_bswap64(x)
+#elif defined(_MSC_VER) && (_MSC_VER >= 1400)
+#pragma intrinsic(_byteswap_uint64)
+#define SDL_Swap64(x) _byteswap_uint64(x)
+#elif defined(__i386__) && !HAS_BROKEN_BSWAP
+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(__x86_64__)
+SDL_FORCE_INLINE Uint64
+SDL_Swap64(Uint64 x)
+{
+  __asm__("bswapq %0": "=r"(x):"0"(x));
+    return x;
+}
+#elif defined(__WATCOMC__) && defined(__386__)
+extern __inline Uint64 SDL_Swap64(Uint64);
+#pragma aux SDL_Swap64 = \
+  "bswap eax"     \
+  "bswap edx"     \
+  "xchg eax,edx"  \
+  parm [eax edx]  \
+  modify [eax edx];
+#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;
+}
+
+/* remove extra macros */
+#undef HAS_BROKEN_BSWAP
+#undef HAS_BUILTIN_BSWAP16
+#undef HAS_BUILTIN_BSWAP32
+#undef HAS_BUILTIN_BSWAP64
+
+/**
+ *  \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: */