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 #include <limits.h>
  39
  40
  41 #if defined(_WIN32) && !defined(__WIN32__)
  42 #define __WIN32__
  43 #endif
  44
  45 #if defined(_MSC_VER)
  46
  47 /* Avoid 'expression is always true' warning */
  48 #pragma warning(disable: 4296)
  49
  50 #endif /* _MSC_VER */
  51
  52
  53 /*
  54  * Alternative stdint.h and stdbool.h headers are supplied in include/c99 for
  55  * systems that lack it.
  56  */
  57 #ifndef __STDC_LIMIT_MACROS
  58 #define __STDC_LIMIT_MACROS 1
  59 #endif
  60 #include <stdint.h>
  61 #include <stdbool.h>
  62
  63
  64 #ifdef __cplusplus
  65 extern "C" {
  66 #endif
  67
  68
  69 #if !defined(__HAIKU__) && !defined(__USE_MISC)
  70 typedef unsigned int       uint;
  71 typedef unsigned short     ushort;
  72 #endif
  73 typedef unsigned char      ubyte;
  74
  75 typedef unsigned char boolean;
  76 #ifndef TRUE
  77 #define TRUE  true
  78 #endif
  79 #ifndef FALSE
  80 #define FALSE false
  81 #endif
  82
  83 #ifndef va_copy
  84 #ifdef __va_copy
  85 #define va_copy(dest, src) __va_copy((dest), (src))
  86 #else
  87 #define va_copy(dest, src) (dest) = (src)
  88 #endif
  89 #endif
  90
  91 /* Function inlining */
  92 #ifndef INLINE
  93 #  ifdef __cplusplus
  94 #    define INLINE inline
  95 #  elif defined(__GNUC__)
  96 #    define INLINE __inline__
  97 #  elif defined(_MSC_VER)
  98 #    define INLINE __inline
  99 #  elif defined(__ICL)
 100 #    define INLINE __inline
 101 #  elif defined(__INTEL_COMPILER)
 102 #    define INLINE inline
 103 #  elif defined(__WATCOMC__) && (__WATCOMC__ >= 1100)
 104 #    define INLINE __inline
 105 #  elif defined(__SUNPRO_C) && defined(__C99FEATURES__)
 106 #    define INLINE inline
 107 #  elif (__STDC_VERSION__ >= 199901L) /* C99 */
 108 #    define INLINE inline
 109 #  else
 110 #    define INLINE
 111 #  endif
 112 #endif
 113
 114 /* Forced function inlining */
 115 #ifndef ALWAYS_INLINE
 116 #  ifdef __GNUC__
 117 #    define ALWAYS_INLINE inline __attribute__((always_inline))
 118 #  elif defined(_MSC_VER)
 119 #    define ALWAYS_INLINE __forceinline
 120 #  else
 121 #    define ALWAYS_INLINE INLINE
 122 #  endif
 123 #endif
 124
 125 /*
 126  * Define the C99 restrict keyword.
 127  *
 128  * See also:
 129  * - http://cellperformance.beyond3d.com/articles/2006/05/demystifying-the-restrict-keyword.html
 130  */
 131 #ifndef restrict
 132 #  if (__STDC_VERSION__ >= 199901L)
 133      /* C99 */
 134 #  elif defined(__SUNPRO_C) && defined(__C99FEATURES__)
 135      /* C99 */
 136 #  elif defined(__GNUC__)
 137 #    define restrict __restrict__
 138 #  elif defined(_MSC_VER)
 139 #    define restrict __restrict
 140 #  else
 141 #    define restrict /* */
 142 #  endif
 143 #endif
 144
 145
 146 /* Function visibility */
 147 #ifndef PUBLIC
 148 #  if defined(__GNUC__) || (defined(__SUNPRO_C) && (__SUNPRO_C >= 0x590))
 149 #    define PUBLIC __attribute__((visibility("default")))
 150 #  elif defined(_MSC_VER)
 151 #    define PUBLIC __declspec(dllexport)
 152 #  else
 153 #    define PUBLIC
 154 #  endif
 155 #endif
 156
 157
 158 /* The __FUNCTION__ gcc variable is generally only used for debugging.
 159  * If we're not using gcc, define __FUNCTION__ as a cpp symbol here.
 160  */
 161 #ifndef __FUNCTION__
 162 # if !defined(__GNUC__)
 163 #  if (__STDC_VERSION__ >= 199901L) /* C99 */ || \
 164     (defined(__SUNPRO_C) && defined(__C99FEATURES__))
 165 #   define __FUNCTION__ __func__
 166 #  else
 167 #   define __FUNCTION__ "<unknown>"
 168 #  endif
 169 # endif
 170 # if defined(_MSC_VER) && _MSC_VER < 1300
 171 #  define __FUNCTION__ "<unknown>"
 172 # endif
 173 #endif
 174 #ifndef __func__
 175 #  if (__STDC_VERSION__ >= 199901L) || \
 176       (defined(__SUNPRO_C) && defined(__C99FEATURES__))
 177        /* __func__ is part of C99 */
 178 #  elif defined(_MSC_VER)
 179 #    if _MSC_VER >= 1300
 180 #      define __func__ __FUNCTION__
 181 #    else
 182 #      define __func__ "<unknown>"
 183 #    endif
 184 #  endif
 185 #endif
 186
 187
 188
 189 /* This should match linux gcc cdecl semantics everywhere, so that we
 190  * just codegen one calling convention on all platforms.
 191  */
 192 #ifdef _MSC_VER
 193 #define PIPE_CDECL __cdecl
 194 #else
 195 #define PIPE_CDECL
 196 #endif
 197
 198
 199
 200 #if defined(__GNUC__)
 201 #define PIPE_DEPRECATED  __attribute__((__deprecated__))
 202 #else
 203 #define PIPE_DEPRECATED
 204 #endif
 205
 206
 207
 208 /* Macros for data alignment. */
 209 #if defined(__GNUC__) || (defined(__SUNPRO_C) && (__SUNPRO_C >= 0x590))
 210
 211 /* See http://gcc.gnu.org/onlinedocs/gcc-4.4.2/gcc/Type-Attributes.html */
 212 #define PIPE_ALIGN_TYPE(_alignment, _type) _type __attribute__((aligned(_alignment)))
 213
 214 /* See http://gcc.gnu.org/onlinedocs/gcc-4.4.2/gcc/Variable-Attributes.html */
 215 #define PIPE_ALIGN_VAR(_alignment) __attribute__((aligned(_alignment)))
 216
 217 #if (__GNUC__ > 4 || (__GNUC__ == 4 &&__GNUC_MINOR__>1)) && !defined(PIPE_ARCH_X86_64)
 218 #define PIPE_ALIGN_STACK __attribute__((force_align_arg_pointer))
 219 #else
 220 #define PIPE_ALIGN_STACK
 221 #endif
 222
 223 #elif defined(_MSC_VER)
 224
 225 /* See http://msdn.microsoft.com/en-us/library/83ythb65.aspx */
 226 #define PIPE_ALIGN_TYPE(_alignment, _type) __declspec(align(_alignment)) _type
 227 #define PIPE_ALIGN_VAR(_alignment) __declspec(align(_alignment))
 228
 229 #define PIPE_ALIGN_STACK
 230
 231 #elif defined(SWIG)
 232
 233 #define PIPE_ALIGN_TYPE(_alignment, _type) _type
 234 #define PIPE_ALIGN_VAR(_alignment)
 235
 236 #define PIPE_ALIGN_STACK
 237
 238 #else
 239
 240 #error "Unsupported compiler"
 241
 242 #endif
 243
 244
 245 #if defined(__GNUC__)
 246
 247 #define PIPE_READ_WRITE_BARRIER() __asm__("":::"memory")
 248
 249 #elif defined(_MSC_VER)
 250
 251 void _ReadWriteBarrier(void);
 252 #pragma intrinsic(_ReadWriteBarrier)
 253 #define PIPE_READ_WRITE_BARRIER() _ReadWriteBarrier()
 254
 255 #else
 256
 257 #warning "Unsupported compiler"
 258 #define PIPE_READ_WRITE_BARRIER() /* */
 259
 260 #endif
 261
 262
 263 /* You should use these macros to mark if blocks where the if condition
 264  * is either likely to be true, or unlikely to be true.
 265  *
 266  * This will inform human readers of this fact, and will also inform
 267  * the compiler, who will in turn inform the CPU.
 268  *
 269  * CPUs often start executing code inside the if or the else blocks
 270  * without knowing whether the condition is true or not, and will have
 271  * to throw the work away if they find out later they executed the
 272  * wrong part of the if.
 273  *
 274  * If these macros are used, the CPU is more likely to correctly predict
 275  * the right path, and will avoid speculatively executing the wrong branch,
 276  * thus not throwing away work, resulting in better performance.
 277  *
 278  * In light of this, it is also a good idea to mark as "likely" a path
 279  * which is not necessarily always more likely, but that will benefit much
 280  * more from performance improvements since it is already much faster than
 281  * the other path, or viceversa with "unlikely".
 282  *
 283  * Example usage:
 284  * if(unlikely(do_we_need_a_software_fallback()))
 285  *    do_software_fallback();
 286  * else
 287  *    render_with_gpu();
 288  *
 289  * The macros follow the Linux kernel convention, and more examples can
 290  * be found there.
 291  *
 292  * Note that profile guided optimization can offer better results, but
 293  * needs an appropriate coverage suite and does not inform human readers.
 294  */
 295 #ifndef likely
 296 #  if defined(__GNUC__)
 297 #    define likely(x)   __builtin_expect(!!(x), 1)
 298 #    define unlikely(x) __builtin_expect(!!(x), 0)
 299 #  else
 300 #    define likely(x)   (x)
 301 #    define unlikely(x) (x)
 302 #  endif
 303 #endif
 304
 305
 306 #if defined(__cplusplus)
 307 }
 308 #endif
 309
 310
 311 #endif /* P_COMPILER_H */