/* * Mesa 3-D graphics library * * Copyright (C) 1999-2008 Brian Paul 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 imports.h * Standard C library function wrappers. * * This file provides wrappers for all the standard C library functions * like malloc(), free(), printf(), getenv(), etc. */ #ifndef IMPORTS_H #define IMPORTS_H #include #include #include #include "util/compiler.h" #include "util/bitscan.h" #include "util/u_memory.h" #ifdef __cplusplus extern "C" { #endif /* * For GL_ARB_vertex_buffer_object we need to treat vertex array pointers * as offsets into buffer stores. Since the vertex array pointer and * buffer store pointer are both pointers and we need to add them, we use * this macro. * Both pointers/offsets are expressed in bytes. */ #define ADD_POINTERS(A, B) ( (uint8_t *) (A) + (uintptr_t) (B) ) /** * Sometimes we treat floats as ints. On x86 systems, moving a float * as an int (thereby using integer registers instead of FP registers) is * a performance win. Typically, this can be done with ordinary casts. * But with gcc's -fstrict-aliasing flag (which defaults to on in gcc 3.0) * these casts generate warnings. * The following union typedef is used to solve that. */ typedef union { float f; int i; unsigned u; } fi_type; /*@}*/ /*** *** LOG2: Log base 2 of float ***/ static inline float LOG2(float x) { #if 0 /* This is pretty fast, but not accurate enough (only 2 fractional bits). * Based on code from http://www.stereopsis.com/log2.html */ const float y = x * x * x * x; const unsigned ix = *((unsigned *) &y); const unsigned exp = (ix >> 23) & 0xFF; const int log2 = ((int) exp) - 127; return (float) log2 * (1.0 / 4.0); /* 4, because of x^4 above */ #endif /* Pretty fast, and accurate. * Based on code from http://www.flipcode.com/totd/ */ fi_type num; int log_2; num.f = x; log_2 = ((num.i >> 23) & 255) - 128; num.i &= ~(255 << 23); num.i += 127 << 23; num.f = ((-1.0f/3) * num.f + 2) * num.f - 2.0f/3; return num.f + log_2; } /** * finite macro. */ #if defined(_MSC_VER) # define finite _finite #endif /*** *** IS_INF_OR_NAN: test if float is infinite or NaN ***/ #if defined(isfinite) #define IS_INF_OR_NAN(x) (!isfinite(x)) #elif defined(finite) #define IS_INF_OR_NAN(x) (!finite(x)) #elif defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L #define IS_INF_OR_NAN(x) (!isfinite(x)) #else #define IS_INF_OR_NAN(x) (!finite(x)) #endif /** * Convert float to int by rounding to nearest integer, away from zero. */ static inline int IROUND(float f) { return (int) ((f >= 0.0F) ? (f + 0.5F) : (f - 0.5F)); } /** * Convert double to int by rounding to nearest integer, away from zero. */ static inline int IROUNDD(double d) { return (int) ((d >= 0.0) ? (d + 0.5) : (d - 0.5)); } /** * Convert float to int64 by rounding to nearest integer. */ static inline int64_t IROUND64(float f) { return (int64_t) ((f >= 0.0F) ? (f + 0.5F) : (f - 0.5F)); } /** * Convert positive float to int by rounding to nearest integer. */ static inline int IROUND_POS(float f) { assert(f >= 0.0F); return (int) (f + 0.5F); } /** Return (as an integer) floor of float */ static inline int IFLOOR(float f) { #if defined(USE_X86_ASM) && defined(__GNUC__) && defined(__i386__) /* * IEEE floor for computers that round to nearest or even. * 'f' must be between -4194304 and 4194303. * This floor operation is done by "(iround(f + .5) + iround(f - .5)) >> 1", * but uses some IEEE specific tricks for better speed. * Contributed by Josh Vanderhoof */ int ai, bi; double af, bf; af = (3 << 22) + 0.5 + (double)f; bf = (3 << 22) + 0.5 - (double)f; /* GCC generates an extra fstp/fld without this. */ __asm__ ("fstps %0" : "=m" (ai) : "t" (af) : "st"); __asm__ ("fstps %0" : "=m" (bi) : "t" (bf) : "st"); return (ai - bi) >> 1; #else int ai, bi; double af, bf; fi_type u; af = (3 << 22) + 0.5 + (double)f; bf = (3 << 22) + 0.5 - (double)f; u.f = (float) af; ai = u.i; u.f = (float) bf; bi = u.i; return (ai - bi) >> 1; #endif } /** * Is x a power of two? */ static inline int _mesa_is_pow_two(int x) { return !(x & (x - 1)); } /** * Round given integer to next higer power of two * If X is zero result is undefined. * * Source for the fallback implementation is * Sean Eron Anderson's webpage "Bit Twiddling Hacks" * http://graphics.stanford.edu/~seander/bithacks.html * * When using builtin function have to do some work * for case when passed values 1 to prevent hiting * undefined result from __builtin_clz. Undefined * results would be different depending on optimization * level used for build. */ static inline int32_t _mesa_next_pow_two_32(uint32_t x) { #ifdef HAVE___BUILTIN_CLZ uint32_t y = (x != 1); return (1 + y) << ((__builtin_clz(x - y) ^ 31) ); #else x--; x |= x >> 1; x |= x >> 2; x |= x >> 4; x |= x >> 8; x |= x >> 16; x++; return x; #endif } static inline int64_t _mesa_next_pow_two_64(uint64_t x) { #ifdef HAVE___BUILTIN_CLZLL uint64_t y = (x != 1); STATIC_ASSERT(sizeof(x) == sizeof(long long)); return (1 + y) << ((__builtin_clzll(x - y) ^ 63)); #else x--; x |= x >> 1; x |= x >> 2; x |= x >> 4; x |= x >> 8; x |= x >> 16; x |= x >> 32; x++; return x; #endif } /* * Returns the floor form of binary logarithm for a 32-bit integer. */ static inline unsigned _mesa_logbase2(unsigned n) { #ifdef HAVE___BUILTIN_CLZ return (31 - __builtin_clz(n | 1)); #else unsigned pos = 0; if (n >= 1<<16) { n >>= 16; pos += 16; } if (n >= 1<< 8) { n >>= 8; pos += 8; } if (n >= 1<< 4) { n >>= 4; pos += 4; } if (n >= 1<< 2) { n >>= 2; pos += 2; } if (n >= 1<< 1) { pos += 1; } return pos; #endif } /********************************************************************** * Functions */ extern void * _mesa_align_malloc( size_t bytes, unsigned long alignment ); extern void * _mesa_align_calloc( size_t bytes, unsigned long alignment ); extern void _mesa_align_free( void *ptr ); extern void * _mesa_align_realloc(void *oldBuffer, size_t oldSize, size_t newSize, unsigned long alignment); extern int _mesa_snprintf( char *str, size_t size, const char *fmt, ... ) PRINTFLIKE(3, 4); extern int _mesa_vsnprintf(char *str, size_t size, const char *fmt, va_list arg); #if defined(_WIN32) && !defined(HAVE_STRTOK_R) #define strtok_r strtok_s #endif #ifdef __cplusplus } #endif #endif /* IMPORTS_H */