src/gallium/include/pipe/p_compiler.h

   1 /**************************************************************************
   2  *
   3  * Copyright 2007-2008 Tungsten Graphics, Inc., Cedar Park, Texas.
   4  * All Rights Reserved.
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a
   7  * copy of this software and associated documentation files (the
   8  * "Software"), to deal in the Software without restriction, including
   9  * without limitation the rights to use, copy, modify, merge, publish,
  10  * distribute, sub license, and/or sell copies of the Software, and to
  11  * permit persons to whom the Software is furnished to do so, subject to
  12  * the following conditions:
  13  *
  14  * The above copyright notice and this permission notice (including the
  15  * next paragraph) shall be included in all copies or substantial portions
  16  * of the Software.
  17  *
  18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  19  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  20  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
  21  * IN NO EVENT SHALL TUNGSTEN GRAPHICS AND/OR ITS SUPPLIERS BE LIABLE FOR
  22  * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
  23  * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
  24  * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  25  *
  26  **************************************************************************/
  27
  28 #ifndef P_COMPILER_H
  29 #define P_COMPILER_H
  30
  31
  32 #include "p_config.h"
  33
  34 #include <stdlib.h>
  35 #include <string.h>
  36 #include <stddef.h>
  37 #include <stdarg.h>
  38
  39
  40 #if defined(_WIN32) && !defined(__WIN32__)
  41 #define __WIN32__
  42 #endif
  43
  44 #if defined(_MSC_VER)
  45
  46 /* Avoid 'expression is always true' warning */
  47 #pragma warning(disable: 4296)
  48
  49 #endif /* _MSC_VER */
  50
  51
  52 /*
  53  * Alternative stdint.h and stdbool.h headers are supplied in include/c99 for
  54  * systems that lack it.
  55  */
  56 #ifndef __STDC_LIMIT_MACROS
  57 #define __STDC_LIMIT_MACROS 1
  58 #endif
  59 #include <stdint.h>
  60 #include <stdbool.h>
  61
  62
  63 #ifdef __cplusplus
  64 extern "C" {
  65 #endif
  66
  67
  68 #if !defined(__HAIKU__) && !defined(__USE_MISC)
  69 typedef unsigned int       uint;
  70 typedef unsigned short     ushort;
  71 #endif
  72 typedef unsigned char      ubyte;
  73
  74 typedef unsigned char boolean;
  75 #ifndef TRUE
  76 #define TRUE  true
  77 #endif
  78 #ifndef FALSE
  79 #define FALSE false
  80 #endif
  81
  82 /* Function inlining */
  83 #ifndef INLINE
  84 #  ifdef __cplusplus
  85 #    define INLINE inline
  86 #  elif defined(__GNUC__)
  87 #    define INLINE __inline__
  88 #  elif defined(_MSC_VER)
  89 #    define INLINE __inline
  90 #  elif defined(__ICL)
  91 #    define INLINE __inline
  92 #  elif defined(__INTEL_COMPILER)
  93 #    define INLINE inline
  94 #  elif defined(__WATCOMC__) && (__WATCOMC__ >= 1100)
  95 #    define INLINE __inline
  96 #  elif defined(__SUNPRO_C) && defined(__C99FEATURES__)
  97 #    define INLINE inline
  98 #  elif (__STDC_VERSION__ >= 199901L) /* C99 */
  99 #    define INLINE inline
 100 #  else
 101 #    define INLINE
 102 #  endif
 103 #endif
 104
 105 /* Forced function inlining */
 106 #ifndef ALWAYS_INLINE
 107 #  ifdef __GNUC__
 108 #    define ALWAYS_INLINE inline __attribute__((always_inline))
 109 #  elif defined(_MSC_VER)
 110 #    define ALWAYS_INLINE __forceinline
 111 #  else
 112 #    define ALWAYS_INLINE INLINE
 113 #  endif
 114 #endif
 115
 116 /* Function visibility */
 117 #ifndef PUBLIC
 118 #  if defined(__GNUC__) || (defined(__SUNPRO_C) && (__SUNPRO_C >= 0x590))
 119 #    define PUBLIC __attribute__((visibility("default")))
 120 #  elif defined(_MSC_VER)
 121 #    define PUBLIC __declspec(dllexport)
 122 #  else
 123 #    define PUBLIC
 124 #  endif
 125 #endif
 126
 127
 128 /* The __FUNCTION__ gcc variable is generally only used for debugging.
 129  * If we're not using gcc, define __FUNCTION__ as a cpp symbol here.
 130  */
 131 #ifndef __FUNCTION__
 132 # if !defined(__GNUC__)
 133 #  if (__STDC_VERSION__ >= 199901L) /* C99 */ || \
 134     (defined(__SUNPRO_C) && defined(__C99FEATURES__))
 135 #   define __FUNCTION__ __func__
 136 #  else
 137 #   define __FUNCTION__ "<unknown>"
 138 #  endif
 139 # endif
 140 # if defined(_MSC_VER) && _MSC_VER < 1300
 141 #  define __FUNCTION__ "<unknown>"
 142 # endif
 143 #endif
 144
 145
 146
 147 /* This should match linux gcc cdecl semantics everywhere, so that we
 148  * just codegen one calling convention on all platforms.
 149  */
 150 #ifdef _MSC_VER
 151 #define PIPE_CDECL __cdecl
 152 #else
 153 #define PIPE_CDECL
 154 #endif
 155
 156
 157
 158 #if defined(__GNUC__)
 159 #define PIPE_DEPRECATED  __attribute__((__deprecated__))
 160 #else
 161 #define PIPE_DEPRECATED
 162 #endif
 163
 164
 165
 166 /* Macros for data alignment. */
 167 #if defined(__GNUC__) || (defined(__SUNPRO_C) && (__SUNPRO_C >= 0x590))
 168
 169 /* See http://gcc.gnu.org/onlinedocs/gcc-4.4.2/gcc/Type-Attributes.html */
 170 #define PIPE_ALIGN_TYPE(_alignment, _type) _type __attribute__((aligned(_alignment)))
 171
 172 /* See http://gcc.gnu.org/onlinedocs/gcc-4.4.2/gcc/Variable-Attributes.html */
 173 #define PIPE_ALIGN_VAR(_alignment) __attribute__((aligned(_alignment)))
 174
 175 #if (__GNUC__ > 4 || (__GNUC__ == 4 &&__GNUC_MINOR__>1)) && !defined(PIPE_ARCH_X86_64)
 176 #define PIPE_ALIGN_STACK __attribute__((force_align_arg_pointer))
 177 #else
 178 #define PIPE_ALIGN_STACK
 179 #endif
 180
 181 #elif defined(_MSC_VER)
 182
 183 /* See http://msdn.microsoft.com/en-us/library/83ythb65.aspx */
 184 #define PIPE_ALIGN_TYPE(_alignment, _type) __declspec(align(_alignment)) _type
 185 #define PIPE_ALIGN_VAR(_alignment) __declspec(align(_alignment))
 186
 187 #define PIPE_ALIGN_STACK
 188
 189 #elif defined(SWIG)
 190
 191 #define PIPE_ALIGN_TYPE(_alignment, _type) _type
 192 #define PIPE_ALIGN_VAR(_alignment)
 193
 194 #define PIPE_ALIGN_STACK
 195
 196 #else
 197
 198 #error "Unsupported compiler"
 199
 200 #endif
 201
 202
 203 #if defined(__GNUC__)
 204
 205 #define PIPE_READ_WRITE_BARRIER() __asm__("":::"memory")
 206
 207 #elif defined(_MSC_VER)
 208
 209 void _ReadWriteBarrier(void);
 210 #pragma intrinsic(_ReadWriteBarrier)
 211 #define PIPE_READ_WRITE_BARRIER() _ReadWriteBarrier()
 212
 213 #else
 214
 215 #warning "Unsupported compiler"
 216 #define PIPE_READ_WRITE_BARRIER() /* */
 217
 218 #endif
 219
 220
 221 /* You should use these macros to mark if blocks where the if condition
 222  * is either likely to be true, or unlikely to be true.
 223  *
 224  * This will inform human readers of this fact, and will also inform
 225  * the compiler, who will in turn inform the CPU.
 226  *
 227  * CPUs often start executing code inside the if or the else blocks
 228  * without knowing whether the condition is true or not, and will have
 229  * to throw the work away if they find out later they executed the
 230  * wrong part of the if.
 231  *
 232  * If these macros are used, the CPU is more likely to correctly predict
 233  * the right path, and will avoid speculatively executing the wrong branch,
 234  * thus not throwing away work, resulting in better performance.
 235  *
 236  * In light of this, it is also a good idea to mark as "likely" a path
 237  * which is not necessarily always more likely, but that will benefit much
 238  * more from performance improvements since it is already much faster than
 239  * the other path, or viceversa with "unlikely".
 240  *
 241  * Example usage:
 242  * if(unlikely(do_we_need_a_software_fallback()))
 243  *    do_software_fallback();
 244  * else
 245  *    render_with_gpu();
 246  *
 247  * The macros follow the Linux kernel convention, and more examples can
 248  * be found there.
 249  *
 250  * Note that profile guided optimization can offer better results, but
 251  * needs an appropriate coverage suite and does not inform human readers.
 252  */
 253 #ifdef __GNUC__
 254 #define likely(x) __builtin_expect(!!(x), 1)
 255 #define unlikely(x) __builtin_expect(!!(x), 0)
 256 #else
 257 #define likely(x) !!(x)
 258 #define unlikely(x) !!(x)
 259 #endif
 260
 261
 262 #if defined(__cplusplus)
 263 }
 264 #endif
 265
 266
 267 #endif /* P_COMPILER_H */