mesa/src/util/compiler.h

99 lines
3.0 KiB
C

/*
* Mesa 3-D graphics library
*
* Copyright (C) 1999-2008 Brian Paul All Rights Reserved.
* Copyright (C) 2009 VMware, Inc. All Rights Reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included
* in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
* OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
* OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
* ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
* OTHER DEALINGS IN THE SOFTWARE.
*/
/**
* \file compiler.h
* Compiler-related stuff.
*/
#ifndef COMPILER_H
#define COMPILER_H
#include <assert.h>
#include "util/macros.h"
/**
* Either define MESA_BIG_ENDIAN or MESA_LITTLE_ENDIAN, and CPU_TO_LE32.
* Do not use these unless absolutely necessary!
* Try to use a runtime test instead.
* For now, only used by some DRI hardware drivers for color/texel packing.
*/
#if defined(BYTE_ORDER) && defined(BIG_ENDIAN) && BYTE_ORDER == BIG_ENDIAN
#if defined(__linux__)
#include <byteswap.h>
#define CPU_TO_LE32( x ) bswap_32( x )
#elif defined(__APPLE__)
#include <CoreFoundation/CFByteOrder.h>
#define CPU_TO_LE32( x ) CFSwapInt32HostToLittle( x )
#elif defined(__OpenBSD__)
#include <sys/types.h>
#define CPU_TO_LE32( x ) htole32( x )
#else /*__linux__ */
#include <sys/endian.h>
#define CPU_TO_LE32( x ) bswap32( x )
#endif /*__linux__*/
#define MESA_BIG_ENDIAN 1
#else
#define CPU_TO_LE32( x ) ( x )
#define MESA_LITTLE_ENDIAN 1
#endif
#define LE32_TO_CPU( x ) CPU_TO_LE32( x )
#define IEEE_ONE 0x3f800000
#ifndef __has_attribute
# define __has_attribute(x) 0
#endif
#if defined(__has_cpp_attribute) && defined(__clang__)
/* We do not do the same trick as __has_attribute because parsing
* clang::fallthrough in the preprocessor fails in GCC. */
# define HAS_CLANG_FALLTHROUGH __has_cpp_attribute(clang::fallthrough)
#else
# define HAS_CLANG_FALLTHROUGH 0
#endif
#if __cplusplus >= 201703L || __STDC_VERSION__ > 201710L
/* Standard C++17/C23 attribute */
#define FALLTHROUGH [[fallthrough]]
#elif HAS_CLANG_FALLTHROUGH
/* Clang++ specific */
#define FALLTHROUGH [[clang::fallthrough]]
#elif __has_attribute(fallthrough)
/* Non-standard but supported by at least gcc and clang */
#define FALLTHROUGH __attribute__((fallthrough))
#else
#define FALLTHROUGH do { } while(0)
#endif
#endif /* COMPILER_H */