2 * Mesa 3-D graphics library
4 * Copyright (C) 1999-2008 Brian Paul All Rights Reserved.
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:
13 * The above copyright notice and this permission notice shall be included
14 * in all copies or substantial portions of the Software.
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.
28 * Standard C library function wrappers.
30 * This file provides wrappers for all the standard C library functions
31 * like malloc(), free(), printf(), getenv(), etc.
45 #include "util/bitscan.h"
52 /**********************************************************************/
56 /** Allocate a structure of type \p T */
57 #define MALLOC_STRUCT(T) (struct T *) malloc(sizeof(struct T))
58 /** Allocate and zero a structure of type \p T */
59 #define CALLOC_STRUCT(T) (struct T *) calloc(1, sizeof(struct T))
65 * For GL_ARB_vertex_buffer_object we need to treat vertex array pointers
66 * as offsets into buffer stores. Since the vertex array pointer and
67 * buffer store pointer are both pointers and we need to add them, we use
69 * Both pointers/offsets are expressed in bytes.
71 #define ADD_POINTERS(A, B) ( (GLubyte *) (A) + (uintptr_t) (B) )
75 * Sometimes we treat GLfloats as GLints. On x86 systems, moving a float
76 * as an int (thereby using integer registers instead of FP registers) is
77 * a performance win. Typically, this can be done with ordinary casts.
78 * But with gcc's -fstrict-aliasing flag (which defaults to on in gcc 3.0)
79 * these casts generate warnings.
80 * The following union typedef is used to solve that.
82 typedef union { GLfloat f
; GLint i
; GLuint u
; } fi_type
;
87 #define strcasecmp(s1, s2) _stricmp(s1, s2)
93 *** LOG2: Log base 2 of float
95 static inline GLfloat
LOG2(GLfloat x
)
98 /* This is pretty fast, but not accurate enough (only 2 fractional bits).
99 * Based on code from http://www.stereopsis.com/log2.html
101 const GLfloat y
= x
* x
* x
* x
;
102 const GLuint ix
= *((GLuint
*) &y
);
103 const GLuint exp
= (ix
>> 23) & 0xFF;
104 const GLint log2
= ((GLint
) exp
) - 127;
105 return (GLfloat
) log2
* (1.0 / 4.0); /* 4, because of x^4 above */
107 /* Pretty fast, and accurate.
108 * Based on code from http://www.flipcode.com/totd/
113 log_2
= ((num
.i
>> 23) & 255) - 128;
114 num
.i
&= ~(255 << 23);
116 num
.f
= ((-1.0f
/3) * num
.f
+ 2) * num
.f
- 2.0f
/3;
117 return num
.f
+ log_2
;
125 #if defined(_MSC_VER)
126 # define finite _finite
131 *** IS_INF_OR_NAN: test if float is infinite or NaN
133 #if defined(isfinite)
134 #define IS_INF_OR_NAN(x) (!isfinite(x))
135 #elif defined(finite)
136 #define IS_INF_OR_NAN(x) (!finite(x))
137 #elif defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L
138 #define IS_INF_OR_NAN(x) (!isfinite(x))
140 #define IS_INF_OR_NAN(x) (!finite(x))
145 * Convert float to int by rounding to nearest integer, away from zero.
147 static inline int IROUND(float f
)
149 return (int) ((f
>= 0.0F
) ? (f
+ 0.5F
) : (f
- 0.5F
));
153 * Convert double to int by rounding to nearest integer, away from zero.
155 static inline int IROUNDD(double d
)
157 return (int) ((d
>= 0.0) ? (d
+ 0.5) : (d
- 0.5));
161 * Convert float to int64 by rounding to nearest integer.
163 static inline GLint64
IROUND64(float f
)
165 return (GLint64
) ((f
>= 0.0F
) ? (f
+ 0.5F
) : (f
- 0.5F
));
170 * Convert positive float to int by rounding to nearest integer.
172 static inline int IROUND_POS(float f
)
175 return (int) (f
+ 0.5F
);
178 /** Return (as an integer) floor of float */
179 static inline int IFLOOR(float f
)
181 #if defined(USE_X86_ASM) && defined(__GNUC__) && defined(__i386__)
183 * IEEE floor for computers that round to nearest or even.
184 * 'f' must be between -4194304 and 4194303.
185 * This floor operation is done by "(iround(f + .5) + iround(f - .5)) >> 1",
186 * but uses some IEEE specific tricks for better speed.
187 * Contributed by Josh Vanderhoof
191 af
= (3 << 22) + 0.5 + (double)f
;
192 bf
= (3 << 22) + 0.5 - (double)f
;
193 /* GCC generates an extra fstp/fld without this. */
194 __asm__ ("fstps %0" : "=m" (ai
) : "t" (af
) : "st");
195 __asm__ ("fstps %0" : "=m" (bi
) : "t" (bf
) : "st");
196 return (ai
- bi
) >> 1;
201 af
= (3 << 22) + 0.5 + (double)f
;
202 bf
= (3 << 22) + 0.5 - (double)f
;
203 u
.f
= (float) af
; ai
= u
.i
;
204 u
.f
= (float) bf
; bi
= u
.i
;
205 return (ai
- bi
) >> 1;
211 * Is x a power of two?
214 _mesa_is_pow_two(int x
)
216 return !(x
& (x
- 1));
220 * Round given integer to next higer power of two
221 * If X is zero result is undefined.
223 * Source for the fallback implementation is
224 * Sean Eron Anderson's webpage "Bit Twiddling Hacks"
225 * http://graphics.stanford.edu/~seander/bithacks.html
227 * When using builtin function have to do some work
228 * for case when passed values 1 to prevent hiting
229 * undefined result from __builtin_clz. Undefined
230 * results would be different depending on optimization
231 * level used for build.
233 static inline int32_t
234 _mesa_next_pow_two_32(uint32_t x
)
236 #ifdef HAVE___BUILTIN_CLZ
237 uint32_t y
= (x
!= 1);
238 return (1 + y
) << ((__builtin_clz(x
- y
) ^ 31) );
251 static inline int64_t
252 _mesa_next_pow_two_64(uint64_t x
)
254 #ifdef HAVE___BUILTIN_CLZLL
255 uint64_t y
= (x
!= 1);
256 STATIC_ASSERT(sizeof(x
) == sizeof(long long));
257 return (1 + y
) << ((__builtin_clzll(x
- y
) ^ 63));
273 * Returns the floor form of binary logarithm for a 32-bit integer.
276 _mesa_logbase2(GLuint n
)
278 #ifdef HAVE___BUILTIN_CLZ
279 return (31 - __builtin_clz(n
| 1));
282 if (n
>= 1<<16) { n
>>= 16; pos
+= 16; }
283 if (n
>= 1<< 8) { n
>>= 8; pos
+= 8; }
284 if (n
>= 1<< 4) { n
>>= 4; pos
+= 4; }
285 if (n
>= 1<< 2) { n
>>= 2; pos
+= 2; }
286 if (n
>= 1<< 1) { pos
+= 1; }
293 * Return 1 if this is a little endian machine, 0 if big endian.
295 static inline GLboolean
296 _mesa_little_endian(void)
298 const GLuint ui
= 1; /* intentionally not static */
299 return *((const GLubyte
*) &ui
);
304 /**********************************************************************
309 _mesa_align_malloc( size_t bytes
, unsigned long alignment
);
312 _mesa_align_calloc( size_t bytes
, unsigned long alignment
);
315 _mesa_align_free( void *ptr
);
318 _mesa_align_realloc(void *oldBuffer
, size_t oldSize
, size_t newSize
,
319 unsigned long alignment
);
322 _mesa_exec_malloc( GLuint size
);
325 _mesa_exec_free( void *addr
);
328 #ifdef HAVE___BUILTIN_POPCOUNT
329 #define _mesa_bitcount(i) __builtin_popcount(i)
332 _mesa_bitcount(unsigned int n
);
335 #ifdef HAVE___BUILTIN_POPCOUNTLL
336 #define _mesa_bitcount_64(i) __builtin_popcountll(i)
339 _mesa_bitcount_64(uint64_t n
);
344 _mesa_half_is_negative(GLhalfARB h
)
350 _mesa_str_checksum(const char *str
);
353 _mesa_snprintf( char *str
, size_t size
, const char *fmt
, ... ) PRINTFLIKE(3, 4);
356 _mesa_vsnprintf(char *str
, size_t size
, const char *fmt
, va_list arg
);
359 #if defined(_MSC_VER) && !defined(snprintf)
360 #define snprintf _snprintf
363 #if defined(_WIN32) && !defined(strtok_r)
364 #define strtok_r strtok_s
372 #endif /* IMPORTS_H */