src/mesa/main/imports.h

   1 /*
   2  * Mesa 3-D graphics library
   3  *
   4  * Copyright (C) 1999-2008  Brian Paul   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 "Software"),
   8  * to deal in the Software without restriction, including without limitation
   9  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  10  * and/or sell copies of the Software, and to permit persons to whom the
  11  * Software is furnished to do so, subject to the following conditions:
  12  *
  13  * The above copyright notice and this permission notice shall be included
  14  * in all copies or substantial portions of the Software.
  15  *
  16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  17  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
  20  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
  21  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
  22  * OTHER DEALINGS IN THE SOFTWARE.
  23  */
  24
  25
  26 /**
  27  * \file imports.h
  28  * Standard C library function wrappers.
  29  *
  30  * This file provides wrappers for all the standard C library functions
  31  * like malloc(), free(), printf(), getenv(), etc.
  32  */
  33
  34
  35 #ifndef IMPORTS_H
  36 #define IMPORTS_H
  37
  38
  39 #include <stdlib.h>
  40 #include <stdarg.h>
  41 #include <string.h>
  42 #include "compiler.h"
  43 #include "glheader.h"
  44 #include "errors.h"
  45
  46 #ifdef __cplusplus
  47 extern "C" {
  48 #endif
  49
  50
  51 /**********************************************************************/
  52 /** Memory macros */
  53 /*@{*/
  54
  55 /** Allocate a structure of type \p T */
  56 #define MALLOC_STRUCT(T)   (struct T *) malloc(sizeof(struct T))
  57 /** Allocate and zero a structure of type \p T */
  58 #define CALLOC_STRUCT(T)   (struct T *) calloc(1, sizeof(struct T))
  59
  60 /*@}*/
  61
  62
  63 /*
  64  * For GL_ARB_vertex_buffer_object we need to treat vertex array pointers
  65  * as offsets into buffer stores.  Since the vertex array pointer and
  66  * buffer store pointer are both pointers and we need to add them, we use
  67  * this macro.
  68  * Both pointers/offsets are expressed in bytes.
  69  */
  70 #define ADD_POINTERS(A, B)  ( (GLubyte *) (A) + (uintptr_t) (B) )
  71
  72
  73 /**
  74  * Sometimes we treat GLfloats as GLints.  On x86 systems, moving a float
  75  * as a int (thereby using integer registers instead of FP registers) is
  76  * a performance win.  Typically, this can be done with ordinary casts.
  77  * But with gcc's -fstrict-aliasing flag (which defaults to on in gcc 3.0)
  78  * these casts generate warnings.
  79  * The following union typedef is used to solve that.
  80  */
  81 typedef union { GLfloat f; GLint i; GLuint u; } fi_type;
  82
  83
  84
  85 #if defined(_MSC_VER)
  86 #if _MSC_VER < 1800  /* Not req'd on VS2013 and above */
  87 #define strtoll(p, e, b) _strtoi64(p, e, b)
  88 #endif /* _MSC_VER < 1800 */
  89 #define strcasecmp(s1, s2) _stricmp(s1, s2)
  90 #endif
  91 /*@}*/
  92
  93
  94 /***
  95  *** LOG2: Log base 2 of float
  96  ***/
  97 static inline GLfloat LOG2(GLfloat x)
  98 {
  99 #if 0
 100    /* This is pretty fast, but not accurate enough (only 2 fractional bits).
 101     * Based on code from http://www.stereopsis.com/log2.html
 102     */
 103    const GLfloat y = x * x * x * x;
 104    const GLuint ix = *((GLuint *) &y);
 105    const GLuint exp = (ix >> 23) & 0xFF;
 106    const GLint log2 = ((GLint) exp) - 127;
 107    return (GLfloat) log2 * (1.0 / 4.0);  /* 4, because of x^4 above */
 108 #endif
 109    /* Pretty fast, and accurate.
 110     * Based on code from http://www.flipcode.com/totd/
 111     */
 112    fi_type num;
 113    GLint log_2;
 114    num.f = x;
 115    log_2 = ((num.i >> 23) & 255) - 128;
 116    num.i &= ~(255 << 23);
 117    num.i += 127 << 23;
 118    num.f = ((-1.0f/3) * num.f + 2) * num.f - 2.0f/3;
 119    return num.f + log_2;
 120 }
 121
 122
 123
 124 /**
 125  * finite macro.
 126  */
 127 #if defined(_MSC_VER)
 128 #  define finite _finite
 129 #endif
 130
 131
 132 /***
 133  *** IS_INF_OR_NAN: test if float is infinite or NaN
 134  ***/
 135 #if defined(isfinite)
 136 #define IS_INF_OR_NAN(x)        (!isfinite(x))
 137 #elif defined(finite)
 138 #define IS_INF_OR_NAN(x)        (!finite(x))
 139 #elif defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L
 140 #define IS_INF_OR_NAN(x)        (!isfinite(x))
 141 #else
 142 #define IS_INF_OR_NAN(x)        (!finite(x))
 143 #endif
 144
 145
 146 /**
 147  * Convert float to int by rounding to nearest integer, away from zero.
 148  */
 149 static inline int IROUND(float f)
 150 {
 151    return (int) ((f >= 0.0F) ? (f + 0.5F) : (f - 0.5F));
 152 }
 153
 154
 155 /**
 156  * Convert float to int64 by rounding to nearest integer.
 157  */
 158 static inline GLint64 IROUND64(float f)
 159 {
 160    return (GLint64) ((f >= 0.0F) ? (f + 0.5F) : (f - 0.5F));
 161 }
 162
 163
 164 /**
 165  * Convert positive float to int by rounding to nearest integer.
 166  */
 167 static inline int IROUND_POS(float f)
 168 {
 169    assert(f >= 0.0F);
 170    return (int) (f + 0.5F);
 171 }
 172
 173 /** Return (as an integer) floor of float */
 174 static inline int IFLOOR(float f)
 175 {
 176 #if defined(USE_X86_ASM) && defined(__GNUC__) && defined(__i386__)
 177    /*
 178     * IEEE floor for computers that round to nearest or even.
 179     * 'f' must be between -4194304 and 4194303.
 180     * This floor operation is done by "(iround(f + .5) + iround(f - .5)) >> 1",
 181     * but uses some IEEE specific tricks for better speed.
 182     * Contributed by Josh Vanderhoof
 183     */
 184    int ai, bi;
 185    double af, bf;
 186    af = (3 << 22) + 0.5 + (double)f;
 187    bf = (3 << 22) + 0.5 - (double)f;
 188    /* GCC generates an extra fstp/fld without this. */
 189    __asm__ ("fstps %0" : "=m" (ai) : "t" (af) : "st");
 190    __asm__ ("fstps %0" : "=m" (bi) : "t" (bf) : "st");
 191    return (ai - bi) >> 1;
 192 #else
 193    int ai, bi;
 194    double af, bf;
 195    fi_type u;
 196    af = (3 << 22) + 0.5 + (double)f;
 197    bf = (3 << 22) + 0.5 - (double)f;
 198    u.f = (float) af;  ai = u.i;
 199    u.f = (float) bf;  bi = u.i;
 200    return (ai - bi) >> 1;
 201 #endif
 202 }
 203
 204
 205 /**
 206  * Is x a power of two?
 207  */
 208 static inline int
 209 _mesa_is_pow_two(int x)
 210 {
 211    return !(x & (x - 1));
 212 }
 213
 214 /**
 215  * Round given integer to next higer power of two
 216  * If X is zero result is undefined.
 217  *
 218  * Source for the fallback implementation is
 219  * Sean Eron Anderson's webpage "Bit Twiddling Hacks"
 220  * http://graphics.stanford.edu/~seander/bithacks.html
 221  *
 222  * When using builtin function have to do some work
 223  * for case when passed values 1 to prevent hiting
 224  * undefined result from __builtin_clz. Undefined
 225  * results would be different depending on optimization
 226  * level used for build.
 227  */
 228 static inline int32_t
 229 _mesa_next_pow_two_32(uint32_t x)
 230 {
 231 #ifdef HAVE___BUILTIN_CLZ
 232         uint32_t y = (x != 1);
 233         return (1 + y) << ((__builtin_clz(x - y) ^ 31) );
 234 #else
 235         x--;
 236         x |= x >> 1;
 237         x |= x >> 2;
 238         x |= x >> 4;
 239         x |= x >> 8;
 240         x |= x >> 16;
 241         x++;
 242         return x;
 243 #endif
 244 }
 245
 246 static inline int64_t
 247 _mesa_next_pow_two_64(uint64_t x)
 248 {
 249 #ifdef HAVE___BUILTIN_CLZLL
 250         uint64_t y = (x != 1);
 251         STATIC_ASSERT(sizeof(x) == sizeof(long long));
 252         return (1 + y) << ((__builtin_clzll(x - y) ^ 63));
 253 #else
 254         x--;
 255         x |= x >> 1;
 256         x |= x >> 2;
 257         x |= x >> 4;
 258         x |= x >> 8;
 259         x |= x >> 16;
 260         x |= x >> 32;
 261         x++;
 262         return x;
 263 #endif
 264 }
 265
 266
 267 /*
 268  * Returns the floor form of binary logarithm for a 32-bit integer.
 269  */
 270 static inline GLuint
 271 _mesa_logbase2(GLuint n)
 272 {
 273 #ifdef HAVE___BUILTIN_CLZ
 274    return (31 - __builtin_clz(n | 1));
 275 #else
 276    GLuint pos = 0;
 277    if (n >= 1<<16) { n >>= 16; pos += 16; }
 278    if (n >= 1<< 8) { n >>=  8; pos +=  8; }
 279    if (n >= 1<< 4) { n >>=  4; pos +=  4; }
 280    if (n >= 1<< 2) { n >>=  2; pos +=  2; }
 281    if (n >= 1<< 1) {           pos +=  1; }
 282    return pos;
 283 #endif
 284 }
 285
 286
 287 /**
 288  * Return 1 if this is a little endian machine, 0 if big endian.
 289  */
 290 static inline GLboolean
 291 _mesa_little_endian(void)
 292 {
 293    const GLuint ui = 1; /* intentionally not static */
 294    return *((const GLubyte *) &ui);
 295 }
 296
 297
 298
 299 /**********************************************************************
 300  * Functions
 301  */
 302
 303 extern void *
 304 _mesa_align_malloc( size_t bytes, unsigned long alignment );
 305
 306 extern void *
 307 _mesa_align_calloc( size_t bytes, unsigned long alignment );
 308
 309 extern void
 310 _mesa_align_free( void *ptr );
 311
 312 extern void *
 313 _mesa_align_realloc(void *oldBuffer, size_t oldSize, size_t newSize,
 314                     unsigned long alignment);
 315
 316 extern void *
 317 _mesa_exec_malloc( GLuint size );
 318
 319 extern void
 320 _mesa_exec_free( void *addr );
 321
 322
 323 #ifndef FFS_DEFINED
 324 #define FFS_DEFINED 1
 325 #ifdef HAVE___BUILTIN_FFS
 326 #define ffs __builtin_ffs
 327 #else
 328 extern int ffs(int i);
 329 #endif
 330
 331 #ifdef HAVE___BUILTIN_FFSLL
 332 #define ffsll __builtin_ffsll
 333 #else
 334 extern int ffsll(long long int i);
 335 #endif
 336 #endif /* FFS_DEFINED */
 337
 338
 339 #ifdef HAVE___BUILTIN_POPCOUNT
 340 #define _mesa_bitcount(i) __builtin_popcount(i)
 341 #else
 342 extern unsigned int
 343 _mesa_bitcount(unsigned int n);
 344 #endif
 345
 346 #ifdef HAVE___BUILTIN_POPCOUNTLL
 347 #define _mesa_bitcount_64(i) __builtin_popcountll(i)
 348 #else
 349 extern unsigned int
 350 _mesa_bitcount_64(uint64_t n);
 351 #endif
 352
 353 /**
 354  * Find the last (most significant) bit set in a word.
 355  *
 356  * Essentially ffs() in the reverse direction.
 357  */
 358 static inline unsigned int
 359 _mesa_fls(unsigned int n)
 360 {
 361 #ifdef HAVE___BUILTIN_CLZ
 362    return n == 0 ? 0 : 32 - __builtin_clz(n);
 363 #else
 364    unsigned int v = 1;
 365
 366    if (n == 0)
 367       return 0;
 368
 369    while (n >>= 1)
 370        v++;
 371
 372    return v;
 373 #endif
 374 }
 375
 376 /**
 377  * Find the last (most significant) bit set in a uint64_t value.
 378  *
 379  * Essentially ffsll() in the reverse direction.
 380  */
 381 static inline unsigned int
 382 _mesa_flsll(uint64_t n)
 383 {
 384 #ifdef HAVE___BUILTIN_CLZLL
 385    return n == 0 ? 0 : 64 - __builtin_clzll(n);
 386 #else
 387    unsigned int v = 1;
 388
 389    if (n == 0)
 390       return 0;
 391
 392    while (n >>= 1)
 393        v++;
 394
 395    return v;
 396 #endif
 397 }
 398
 399 static inline bool
 400 _mesa_half_is_negative(GLhalfARB h)
 401 {
 402    return h & 0x8000;
 403 }
 404
 405 extern unsigned int
 406 _mesa_str_checksum(const char *str);
 407
 408 extern int
 409 _mesa_snprintf( char *str, size_t size, const char *fmt, ... ) PRINTFLIKE(3, 4);
 410
 411 extern int
 412 _mesa_vsnprintf(char *str, size_t size, const char *fmt, va_list arg);
 413
 414
 415 #if defined(_MSC_VER) && !defined(snprintf)
 416 #define snprintf _snprintf
 417 #endif
 418
 419 #if defined(_WIN32) && !defined(strtok_r)
 420 #define strtok_r strtok_s
 421 #endif
 422
 423 #ifdef __cplusplus
 424 }
 425 #endif
 426
 427
 428 #endif /* IMPORTS_H */