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-rw-r--r--mesalib/src/gallium/auxiliary/util/u_math.h1326
1 files changed, 663 insertions, 663 deletions
diff --git a/mesalib/src/gallium/auxiliary/util/u_math.h b/mesalib/src/gallium/auxiliary/util/u_math.h
index 0b5284428..9a061e8a9 100644
--- a/mesalib/src/gallium/auxiliary/util/u_math.h
+++ b/mesalib/src/gallium/auxiliary/util/u_math.h
@@ -1,663 +1,663 @@
-/**************************************************************************
- *
- * Copyright 2008 Tungsten Graphics, Inc., Cedar Park, Texas.
- * 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, sub license, 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 (including the
- * next paragraph) 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 NON-INFRINGEMENT.
- * IN NO EVENT SHALL TUNGSTEN GRAPHICS AND/OR ITS SUPPLIERS 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.
- *
- **************************************************************************/
-
-
-/**
- * Math utilities and approximations for common math functions.
- * Reduced precision is usually acceptable in shaders...
- *
- * "fast" is used in the names of functions which are low-precision,
- * or at least lower-precision than the normal C lib functions.
- */
-
-
-#ifndef U_MATH_H
-#define U_MATH_H
-
-
-#include "pipe/p_compiler.h"
-#include "util/u_debug.h"
-
-
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-
-#if defined(PIPE_SUBSYSTEM_WINDOWS_MINIPORT)
-__inline double ceil(double val)
-{
- double ceil_val;
-
- if ((val - (long) val) == 0) {
- ceil_val = val;
- }
- else {
- if (val > 0) {
- ceil_val = (long) val + 1;
- }
- else {
- ceil_val = (long) val;
- }
- }
-
- return ceil_val;
-}
-
-#ifndef PIPE_SUBSYSTEM_WINDOWS_CE_OGL
-__inline double floor(double val)
-{
- double floor_val;
-
- if ((val - (long) val) == 0) {
- floor_val = val;
- }
- else {
- if (val > 0) {
- floor_val = (long) val;
- }
- else {
- floor_val = (long) val - 1;
- }
- }
-
- return floor_val;
-}
-#endif
-
-#pragma function(pow)
-__inline double __cdecl pow(double val, double exponent)
-{
- /* XXX */
- assert(0);
- return 0;
-}
-
-#pragma function(log)
-__inline double __cdecl log(double val)
-{
- /* XXX */
- assert(0);
- return 0;
-}
-
-#pragma function(atan2)
-__inline double __cdecl atan2(double val)
-{
- /* XXX */
- assert(0);
- return 0;
-}
-#else
-#include <math.h>
-#include <stdarg.h>
-#endif
-
-
-#ifndef M_SQRT2
-#define M_SQRT2 1.41421356237309504880
-#endif
-
-
-#if defined(_MSC_VER)
-
-#if _MSC_VER < 1400 && !defined(__cplusplus) || defined(PIPE_SUBSYSTEM_WINDOWS_CE)
-
-static INLINE float cosf( float f )
-{
- return (float) cos( (double) f );
-}
-
-static INLINE float sinf( float f )
-{
- return (float) sin( (double) f );
-}
-
-static INLINE float ceilf( float f )
-{
- return (float) ceil( (double) f );
-}
-
-static INLINE float floorf( float f )
-{
- return (float) floor( (double) f );
-}
-
-static INLINE float powf( float f, float g )
-{
- return (float) pow( (double) f, (double) g );
-}
-
-static INLINE float sqrtf( float f )
-{
- return (float) sqrt( (double) f );
-}
-
-static INLINE float fabsf( float f )
-{
- return (float) fabs( (double) f );
-}
-
-static INLINE float logf( float f )
-{
- return (float) log( (double) f );
-}
-
-#else
-/* Work-around an extra semi-colon in VS 2005 logf definition */
-#ifdef logf
-#undef logf
-#define logf(x) ((float)log((double)(x)))
-#endif /* logf */
-
-#define isfinite(x) _finite((double)(x))
-#define isnan(x) _isnan((double)(x))
-#endif /* _MSC_VER < 1400 && !defined(__cplusplus) */
-
-static INLINE double log2( double x )
-{
- const double invln2 = 1.442695041;
- return log( x ) * invln2;
-}
-
-static INLINE double
-round(double x)
-{
- return x >= 0.0 ? floor(x + 0.5) : ceil(x - 0.5);
-}
-
-static INLINE float
-roundf(float x)
-{
- return x >= 0.0f ? floorf(x + 0.5f) : ceilf(x - 0.5f);
-}
-
-#endif /* _MSC_VER */
-
-
-
-
-
-#define POW2_TABLE_SIZE_LOG2 9
-#define POW2_TABLE_SIZE (1 << POW2_TABLE_SIZE_LOG2)
-#define POW2_TABLE_OFFSET (POW2_TABLE_SIZE/2)
-#define POW2_TABLE_SCALE ((float)(POW2_TABLE_SIZE/2))
-extern float pow2_table[POW2_TABLE_SIZE];
-
-
-/**
- * Initialize math module. This should be called before using any
- * other functions in this module.
- */
-extern void
-util_init_math(void);
-
-
-union fi {
- float f;
- int32_t i;
- uint32_t ui;
-};
-
-
-/**
- * Fast version of 2^x
- * Identity: exp2(a + b) = exp2(a) * exp2(b)
- * Let ipart = int(x)
- * Let fpart = x - ipart;
- * So, exp2(x) = exp2(ipart) * exp2(fpart)
- * Compute exp2(ipart) with i << ipart
- * Compute exp2(fpart) with lookup table.
- */
-static INLINE float
-util_fast_exp2(float x)
-{
- int32_t ipart;
- float fpart, mpart;
- union fi epart;
-
- if(x > 129.00000f)
- return 3.402823466e+38f;
-
- if (x < -126.99999f)
- return 0.0f;
-
- ipart = (int32_t) x;
- fpart = x - (float) ipart;
-
- /* same as
- * epart.f = (float) (1 << ipart)
- * but faster and without integer overflow for ipart > 31
- */
- epart.i = (ipart + 127 ) << 23;
-
- mpart = pow2_table[POW2_TABLE_OFFSET + (int)(fpart * POW2_TABLE_SCALE)];
-
- return epart.f * mpart;
-}
-
-
-/**
- * Fast approximation to exp(x).
- */
-static INLINE float
-util_fast_exp(float x)
-{
- const float k = 1.44269f; /* = log2(e) */
- return util_fast_exp2(k * x);
-}
-
-
-#define LOG2_TABLE_SIZE_LOG2 16
-#define LOG2_TABLE_SCALE (1 << LOG2_TABLE_SIZE_LOG2)
-#define LOG2_TABLE_SIZE (LOG2_TABLE_SCALE + 1)
-extern float log2_table[LOG2_TABLE_SIZE];
-
-
-/**
- * Fast approximation to log2(x).
- */
-static INLINE float
-util_fast_log2(float x)
-{
- union fi num;
- float epart, mpart;
- num.f = x;
- epart = (float)(((num.i & 0x7f800000) >> 23) - 127);
- /* mpart = log2_table[mantissa*LOG2_TABLE_SCALE + 0.5] */
- mpart = log2_table[((num.i & 0x007fffff) + (1 << (22 - LOG2_TABLE_SIZE_LOG2))) >> (23 - LOG2_TABLE_SIZE_LOG2)];
- return epart + mpart;
-}
-
-
-/**
- * Fast approximation to x^y.
- */
-static INLINE float
-util_fast_pow(float x, float y)
-{
- return util_fast_exp2(util_fast_log2(x) * y);
-}
-
-/* Note that this counts zero as a power of two.
- */
-static INLINE boolean
-util_is_power_of_two( unsigned v )
-{
- return (v & (v-1)) == 0;
-}
-
-
-/**
- * Floor(x), returned as int.
- */
-static INLINE int
-util_ifloor(float f)
-{
- int ai, bi;
- double af, bf;
- union fi 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;
-}
-
-
-/**
- * Round float to nearest int.
- */
-static INLINE int
-util_iround(float f)
-{
-#if defined(PIPE_CC_GCC) && defined(PIPE_ARCH_X86)
- int r;
- __asm__ ("fistpl %0" : "=m" (r) : "t" (f) : "st");
- return r;
-#elif defined(PIPE_CC_MSVC) && defined(PIPE_ARCH_X86)
- int r;
- _asm {
- fld f
- fistp r
- }
- return r;
-#else
- if (f >= 0.0f)
- return (int) (f + 0.5f);
- else
- return (int) (f - 0.5f);
-#endif
-}
-
-
-/**
- * Approximate floating point comparison
- */
-static INLINE boolean
-util_is_approx(float a, float b, float tol)
-{
- return fabs(b - a) <= tol;
-}
-
-
-/**
- * Test if x is NaN or +/- infinity.
- */
-static INLINE boolean
-util_is_inf_or_nan(float x)
-{
- union fi tmp;
- tmp.f = x;
- return !(int)((unsigned int)((tmp.i & 0x7fffffff)-0x7f800000) >> 31);
-}
-
-
-/**
- * Find first bit set in word. Least significant bit is 1.
- * Return 0 if no bits set.
- */
-#if defined(_MSC_VER) && _MSC_VER >= 1300 && (_M_IX86 || _M_AMD64 || _M_IA64)
-unsigned char _BitScanForward(unsigned long* Index, unsigned long Mask);
-#pragma intrinsic(_BitScanForward)
-static INLINE
-unsigned long ffs( unsigned long u )
-{
- unsigned long i;
- if (_BitScanForward(&i, u))
- return i + 1;
- else
- return 0;
-}
-#elif defined(PIPE_CC_MSVC) && defined(PIPE_ARCH_X86)
-static INLINE
-unsigned ffs( unsigned u )
-{
- unsigned i;
-
- if (u == 0) {
- return 0;
- }
-
- __asm bsf eax, [u]
- __asm inc eax
- __asm mov [i], eax
-
- return i;
-}
-#elif defined(__MINGW32__)
-#define ffs __builtin_ffs
-#endif
-
-
-/**
- * Return float bits.
- */
-static INLINE unsigned
-fui( float f )
-{
- union fi fi;
- fi.f = f;
- return fi.ui;
-}
-
-
-/**
- * Convert ubyte to float in [0, 1].
- * XXX a 256-entry lookup table would be slightly faster.
- */
-static INLINE float
-ubyte_to_float(ubyte ub)
-{
- return (float) ub * (1.0f / 255.0f);
-}
-
-
-/**
- * Convert float in [0,1] to ubyte in [0,255] with clamping.
- */
-static INLINE ubyte
-float_to_ubyte(float f)
-{
- const int ieee_0996 = 0x3f7f0000; /* 0.996 or so */
- union fi tmp;
-
- tmp.f = f;
- if (tmp.i < 0) {
- return (ubyte) 0;
- }
- else if (tmp.i >= ieee_0996) {
- return (ubyte) 255;
- }
- else {
- tmp.f = tmp.f * (255.0f/256.0f) + 32768.0f;
- return (ubyte) tmp.i;
- }
-}
-
-static INLINE float
-byte_to_float_tex(int8_t b)
-{
- return (b == -128) ? -1.0F : b * 1.0F / 127.0F;
-}
-
-static INLINE int8_t
-float_to_byte_tex(float f)
-{
- return (int8_t) (127.0F * f);
-}
-
-/**
- * Calc log base 2
- */
-static INLINE unsigned
-util_logbase2(unsigned n)
-{
-#if defined(PIPE_CC_GCC) && (PIPE_CC_GCC_VERSION >= 304)
- return ((sizeof(unsigned) * 8 - 1) - __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
-}
-
-
-/**
- * Returns the smallest power of two >= x
- */
-static INLINE unsigned
-util_next_power_of_two(unsigned x)
-{
-#if defined(PIPE_CC_GCC) && (PIPE_CC_GCC_VERSION >= 304)
- if (x <= 1)
- return 1;
-
- return (1 << ((sizeof(unsigned) * 8) - __builtin_clz(x - 1)));
-#else
- unsigned val = x;
-
- if (x <= 1)
- return 1;
-
- if (util_is_power_of_two(x))
- return x;
-
- val--;
- val = (val >> 1) | val;
- val = (val >> 2) | val;
- val = (val >> 4) | val;
- val = (val >> 8) | val;
- val = (val >> 16) | val;
- val++;
- return val;
-#endif
-}
-
-
-/**
- * Return number of bits set in n.
- */
-static INLINE unsigned
-util_bitcount(unsigned n)
-{
-#if defined(PIPE_CC_GCC) && (PIPE_CC_GCC_VERSION >= 304)
- return __builtin_popcount(n);
-#else
- /* K&R classic bitcount.
- *
- * For each iteration, clear the LSB from the bitfield.
- * Requires only one iteration per set bit, instead of
- * one iteration per bit less than highest set bit.
- */
- unsigned bits = 0;
- for (bits; n; bits++) {
- n &= n - 1;
- }
- return bits;
-#endif
-}
-
-
-/**
- * Reverse byte order of a 32 bit word.
- */
-static INLINE uint32_t
-util_bswap32(uint32_t n)
-{
-#if defined(PIPE_CC_GCC) && (PIPE_CC_GCC_VERSION >= 403)
- return __builtin_bswap32(n);
-#else
- return (n >> 24) |
- ((n >> 8) & 0x0000ff00) |
- ((n << 8) & 0x00ff0000) |
- (n << 24);
-#endif
-}
-
-
-/**
- * Reverse byte order of a 16 bit word.
- */
-static INLINE uint16_t
-util_bswap16(uint16_t n)
-{
- return (n >> 8) |
- (n << 8);
-}
-
-
-/**
- * Clamp X to [MIN, MAX].
- * This is a macro to allow float, int, uint, etc. types.
- */
-#define CLAMP( X, MIN, MAX ) ( (X)<(MIN) ? (MIN) : ((X)>(MAX) ? (MAX) : (X)) )
-
-#define MIN2( A, B ) ( (A)<(B) ? (A) : (B) )
-#define MAX2( A, B ) ( (A)>(B) ? (A) : (B) )
-
-#define MIN3( A, B, C ) ((A) < (B) ? MIN2(A, C) : MIN2(B, C))
-#define MAX3( A, B, C ) ((A) > (B) ? MAX2(A, C) : MAX2(B, C))
-
-#define MIN4( A, B, C, D ) ((A) < (B) ? MIN3(A, C, D) : MIN3(B, C, D))
-#define MAX4( A, B, C, D ) ((A) > (B) ? MAX3(A, C, D) : MAX3(B, C, D))
-
-
-/**
- * Align a value, only works pot alignemnts.
- */
-static INLINE int
-align(int value, int alignment)
-{
- return (value + alignment - 1) & ~(alignment - 1);
-}
-
-/**
- * Works like align but on npot alignments.
- */
-static INLINE size_t
-util_align_npot(size_t value, size_t alignment)
-{
- if (value % alignment)
- return value + (alignment - (value % alignment));
- return value;
-}
-
-static INLINE unsigned
-u_minify(unsigned value, unsigned levels)
-{
- return MAX2(1, value >> levels);
-}
-
-#ifndef COPY_4V
-#define COPY_4V( DST, SRC ) \
-do { \
- (DST)[0] = (SRC)[0]; \
- (DST)[1] = (SRC)[1]; \
- (DST)[2] = (SRC)[2]; \
- (DST)[3] = (SRC)[3]; \
-} while (0)
-#endif
-
-
-#ifndef COPY_4FV
-#define COPY_4FV( DST, SRC ) COPY_4V(DST, SRC)
-#endif
-
-
-#ifndef ASSIGN_4V
-#define ASSIGN_4V( DST, V0, V1, V2, V3 ) \
-do { \
- (DST)[0] = (V0); \
- (DST)[1] = (V1); \
- (DST)[2] = (V2); \
- (DST)[3] = (V3); \
-} while (0)
-#endif
-
-
-static INLINE uint32_t util_unsigned_fixed(float value, unsigned frac_bits)
-{
- return value < 0 ? 0 : (uint32_t)(value * (1<<frac_bits));
-}
-
-static INLINE int32_t util_signed_fixed(float value, unsigned frac_bits)
-{
- return (int32_t)(value * (1<<frac_bits));
-}
-
-
-
-#ifdef __cplusplus
-}
-#endif
-
-#endif /* U_MATH_H */
+/**************************************************************************
+ *
+ * Copyright 2008 Tungsten Graphics, Inc., Cedar Park, Texas.
+ * 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, sub license, 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 (including the
+ * next paragraph) 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 NON-INFRINGEMENT.
+ * IN NO EVENT SHALL TUNGSTEN GRAPHICS AND/OR ITS SUPPLIERS 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.
+ *
+ **************************************************************************/
+
+
+/**
+ * Math utilities and approximations for common math functions.
+ * Reduced precision is usually acceptable in shaders...
+ *
+ * "fast" is used in the names of functions which are low-precision,
+ * or at least lower-precision than the normal C lib functions.
+ */
+
+
+#ifndef U_MATH_H
+#define U_MATH_H
+
+
+#include "pipe/p_compiler.h"
+#include "util/u_debug.h"
+
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+
+#if defined(PIPE_SUBSYSTEM_WINDOWS_MINIPORT)
+__inline double ceil(double val)
+{
+ double ceil_val;
+
+ if ((val - (long) val) == 0) {
+ ceil_val = val;
+ }
+ else {
+ if (val > 0) {
+ ceil_val = (long) val + 1;
+ }
+ else {
+ ceil_val = (long) val;
+ }
+ }
+
+ return ceil_val;
+}
+
+#ifndef PIPE_SUBSYSTEM_WINDOWS_CE_OGL
+__inline double floor(double val)
+{
+ double floor_val;
+
+ if ((val - (long) val) == 0) {
+ floor_val = val;
+ }
+ else {
+ if (val > 0) {
+ floor_val = (long) val;
+ }
+ else {
+ floor_val = (long) val - 1;
+ }
+ }
+
+ return floor_val;
+}
+#endif
+
+#pragma function(pow)
+__inline double __cdecl pow(double val, double exponent)
+{
+ /* XXX */
+ assert(0);
+ return 0;
+}
+
+#pragma function(log)
+__inline double __cdecl log(double val)
+{
+ /* XXX */
+ assert(0);
+ return 0;
+}
+
+#pragma function(atan2)
+__inline double __cdecl atan2(double val)
+{
+ /* XXX */
+ assert(0);
+ return 0;
+}
+#else
+#include <math.h>
+#include <stdarg.h>
+#endif
+
+
+#ifndef M_SQRT2
+#define M_SQRT2 1.41421356237309504880
+#endif
+
+
+#if defined(_MSC_VER)
+
+#if _MSC_VER < 1400 && !defined(__cplusplus) || defined(PIPE_SUBSYSTEM_WINDOWS_CE)
+
+static INLINE float cosf( float f )
+{
+ return (float) cos( (double) f );
+}
+
+static INLINE float sinf( float f )
+{
+ return (float) sin( (double) f );
+}
+
+static INLINE float ceilf( float f )
+{
+ return (float) ceil( (double) f );
+}
+
+static INLINE float floorf( float f )
+{
+ return (float) floor( (double) f );
+}
+
+static INLINE float powf( float f, float g )
+{
+ return (float) pow( (double) f, (double) g );
+}
+
+static INLINE float sqrtf( float f )
+{
+ return (float) sqrt( (double) f );
+}
+
+static INLINE float fabsf( float f )
+{
+ return (float) fabs( (double) f );
+}
+
+static INLINE float logf( float f )
+{
+ return (float) log( (double) f );
+}
+
+#else
+/* Work-around an extra semi-colon in VS 2005 logf definition */
+#ifdef logf
+#undef logf
+#define logf(x) ((float)log((double)(x)))
+#endif /* logf */
+
+#define isfinite(x) _finite((double)(x))
+#define isnan(x) _isnan((double)(x))
+#endif /* _MSC_VER < 1400 && !defined(__cplusplus) */
+
+static INLINE double log2( double x )
+{
+ const double invln2 = 1.442695041;
+ return log( x ) * invln2;
+}
+
+static INLINE double
+round(double x)
+{
+ return x >= 0.0 ? floor(x + 0.5) : ceil(x - 0.5);
+}
+
+static INLINE float
+roundf(float x)
+{
+ return x >= 0.0f ? floorf(x + 0.5f) : ceilf(x - 0.5f);
+}
+
+#endif /* _MSC_VER */
+
+
+
+
+
+#define POW2_TABLE_SIZE_LOG2 9
+#define POW2_TABLE_SIZE (1 << POW2_TABLE_SIZE_LOG2)
+#define POW2_TABLE_OFFSET (POW2_TABLE_SIZE/2)
+#define POW2_TABLE_SCALE ((float)(POW2_TABLE_SIZE/2))
+extern float pow2_table[POW2_TABLE_SIZE];
+
+
+/**
+ * Initialize math module. This should be called before using any
+ * other functions in this module.
+ */
+extern void
+util_init_math(void);
+
+
+union fi {
+ float f;
+ int32_t i;
+ uint32_t ui;
+};
+
+
+/**
+ * Fast version of 2^x
+ * Identity: exp2(a + b) = exp2(a) * exp2(b)
+ * Let ipart = int(x)
+ * Let fpart = x - ipart;
+ * So, exp2(x) = exp2(ipart) * exp2(fpart)
+ * Compute exp2(ipart) with i << ipart
+ * Compute exp2(fpart) with lookup table.
+ */
+static INLINE float
+util_fast_exp2(float x)
+{
+ int32_t ipart;
+ float fpart, mpart;
+ union fi epart;
+
+ if(x > 129.00000f)
+ return 3.402823466e+38f;
+
+ if (x < -126.99999f)
+ return 0.0f;
+
+ ipart = (int32_t) x;
+ fpart = x - (float) ipart;
+
+ /* same as
+ * epart.f = (float) (1 << ipart)
+ * but faster and without integer overflow for ipart > 31
+ */
+ epart.i = (ipart + 127 ) << 23;
+
+ mpart = pow2_table[POW2_TABLE_OFFSET + (int)(fpart * POW2_TABLE_SCALE)];
+
+ return epart.f * mpart;
+}
+
+
+/**
+ * Fast approximation to exp(x).
+ */
+static INLINE float
+util_fast_exp(float x)
+{
+ const float k = 1.44269f; /* = log2(e) */
+ return util_fast_exp2(k * x);
+}
+
+
+#define LOG2_TABLE_SIZE_LOG2 16
+#define LOG2_TABLE_SCALE (1 << LOG2_TABLE_SIZE_LOG2)
+#define LOG2_TABLE_SIZE (LOG2_TABLE_SCALE + 1)
+extern float log2_table[LOG2_TABLE_SIZE];
+
+
+/**
+ * Fast approximation to log2(x).
+ */
+static INLINE float
+util_fast_log2(float x)
+{
+ union fi num;
+ float epart, mpart;
+ num.f = x;
+ epart = (float)(((num.i & 0x7f800000) >> 23) - 127);
+ /* mpart = log2_table[mantissa*LOG2_TABLE_SCALE + 0.5] */
+ mpart = log2_table[((num.i & 0x007fffff) + (1 << (22 - LOG2_TABLE_SIZE_LOG2))) >> (23 - LOG2_TABLE_SIZE_LOG2)];
+ return epart + mpart;
+}
+
+
+/**
+ * Fast approximation to x^y.
+ */
+static INLINE float
+util_fast_pow(float x, float y)
+{
+ return util_fast_exp2(util_fast_log2(x) * y);
+}
+
+/* Note that this counts zero as a power of two.
+ */
+static INLINE boolean
+util_is_power_of_two( unsigned v )
+{
+ return (v & (v-1)) == 0;
+}
+
+
+/**
+ * Floor(x), returned as int.
+ */
+static INLINE int
+util_ifloor(float f)
+{
+ int ai, bi;
+ double af, bf;
+ union fi 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;
+}
+
+
+/**
+ * Round float to nearest int.
+ */
+static INLINE int
+util_iround(float f)
+{
+#if defined(PIPE_CC_GCC) && defined(PIPE_ARCH_X86)
+ int r;
+ __asm__ ("fistpl %0" : "=m" (r) : "t" (f) : "st");
+ return r;
+#elif defined(PIPE_CC_MSVC) && defined(PIPE_ARCH_X86)
+ int r;
+ _asm {
+ fld f
+ fistp r
+ }
+ return r;
+#else
+ if (f >= 0.0f)
+ return (int) (f + 0.5f);
+ else
+ return (int) (f - 0.5f);
+#endif
+}
+
+
+/**
+ * Approximate floating point comparison
+ */
+static INLINE boolean
+util_is_approx(float a, float b, float tol)
+{
+ return fabs(b - a) <= tol;
+}
+
+
+/**
+ * Test if x is NaN or +/- infinity.
+ */
+static INLINE boolean
+util_is_inf_or_nan(float x)
+{
+ union fi tmp;
+ tmp.f = x;
+ return !(int)((unsigned int)((tmp.i & 0x7fffffff)-0x7f800000) >> 31);
+}
+
+
+/**
+ * Find first bit set in word. Least significant bit is 1.
+ * Return 0 if no bits set.
+ */
+#if defined(_MSC_VER) && _MSC_VER >= 1300 && (_M_IX86 || _M_AMD64 || _M_IA64)
+unsigned char _BitScanForward(unsigned long* Index, unsigned long Mask);
+#pragma intrinsic(_BitScanForward)
+static INLINE
+unsigned long ffs( unsigned long u )
+{
+ unsigned long i;
+ if (_BitScanForward(&i, u))
+ return i + 1;
+ else
+ return 0;
+}
+#elif defined(PIPE_CC_MSVC) && defined(PIPE_ARCH_X86)
+static INLINE
+unsigned ffs( unsigned u )
+{
+ unsigned i;
+
+ if (u == 0) {
+ return 0;
+ }
+
+ __asm bsf eax, [u]
+ __asm inc eax
+ __asm mov [i], eax
+
+ return i;
+}
+#elif defined(__MINGW32__)
+#define ffs __builtin_ffs
+#endif
+
+
+/**
+ * Return float bits.
+ */
+static INLINE unsigned
+fui( float f )
+{
+ union fi fi;
+ fi.f = f;
+ return fi.ui;
+}
+
+
+/**
+ * Convert ubyte to float in [0, 1].
+ * XXX a 256-entry lookup table would be slightly faster.
+ */
+static INLINE float
+ubyte_to_float(ubyte ub)
+{
+ return (float) ub * (1.0f / 255.0f);
+}
+
+
+/**
+ * Convert float in [0,1] to ubyte in [0,255] with clamping.
+ */
+static INLINE ubyte
+float_to_ubyte(float f)
+{
+ const int ieee_0996 = 0x3f7f0000; /* 0.996 or so */
+ union fi tmp;
+
+ tmp.f = f;
+ if (tmp.i < 0) {
+ return (ubyte) 0;
+ }
+ else if (tmp.i >= ieee_0996) {
+ return (ubyte) 255;
+ }
+ else {
+ tmp.f = tmp.f * (255.0f/256.0f) + 32768.0f;
+ return (ubyte) tmp.i;
+ }
+}
+
+static INLINE float
+byte_to_float_tex(int8_t b)
+{
+ return (b == -128) ? -1.0F : b * 1.0F / 127.0F;
+}
+
+static INLINE int8_t
+float_to_byte_tex(float f)
+{
+ return (int8_t) (127.0F * f);
+}
+
+/**
+ * Calc log base 2
+ */
+static INLINE unsigned
+util_logbase2(unsigned n)
+{
+#if defined(PIPE_CC_GCC) && (PIPE_CC_GCC_VERSION >= 304)
+ return ((sizeof(unsigned) * 8 - 1) - __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
+}
+
+
+/**
+ * Returns the smallest power of two >= x
+ */
+static INLINE unsigned
+util_next_power_of_two(unsigned x)
+{
+#if defined(PIPE_CC_GCC) && (PIPE_CC_GCC_VERSION >= 304)
+ if (x <= 1)
+ return 1;
+
+ return (1 << ((sizeof(unsigned) * 8) - __builtin_clz(x - 1)));
+#else
+ unsigned val = x;
+
+ if (x <= 1)
+ return 1;
+
+ if (util_is_power_of_two(x))
+ return x;
+
+ val--;
+ val = (val >> 1) | val;
+ val = (val >> 2) | val;
+ val = (val >> 4) | val;
+ val = (val >> 8) | val;
+ val = (val >> 16) | val;
+ val++;
+ return val;
+#endif
+}
+
+
+/**
+ * Return number of bits set in n.
+ */
+static INLINE unsigned
+util_bitcount(unsigned n)
+{
+#if defined(PIPE_CC_GCC) && (PIPE_CC_GCC_VERSION >= 304)
+ return __builtin_popcount(n);
+#else
+ /* K&R classic bitcount.
+ *
+ * For each iteration, clear the LSB from the bitfield.
+ * Requires only one iteration per set bit, instead of
+ * one iteration per bit less than highest set bit.
+ */
+ unsigned bits = 0;
+ for (bits; n; bits++) {
+ n &= n - 1;
+ }
+ return bits;
+#endif
+}
+
+
+/**
+ * Reverse byte order of a 32 bit word.
+ */
+static INLINE uint32_t
+util_bswap32(uint32_t n)
+{
+#if defined(PIPE_CC_GCC) && (PIPE_CC_GCC_VERSION >= 403)
+ return __builtin_bswap32(n);
+#else
+ return (n >> 24) |
+ ((n >> 8) & 0x0000ff00) |
+ ((n << 8) & 0x00ff0000) |
+ (n << 24);
+#endif
+}
+
+
+/**
+ * Reverse byte order of a 16 bit word.
+ */
+static INLINE uint16_t
+util_bswap16(uint16_t n)
+{
+ return (n >> 8) |
+ (n << 8);
+}
+
+
+/**
+ * Clamp X to [MIN, MAX].
+ * This is a macro to allow float, int, uint, etc. types.
+ */
+#define CLAMP( X, MIN, MAX ) ( (X)<(MIN) ? (MIN) : ((X)>(MAX) ? (MAX) : (X)) )
+
+#define MIN2( A, B ) ( (A)<(B) ? (A) : (B) )
+#define MAX2( A, B ) ( (A)>(B) ? (A) : (B) )
+
+#define MIN3( A, B, C ) ((A) < (B) ? MIN2(A, C) : MIN2(B, C))
+#define MAX3( A, B, C ) ((A) > (B) ? MAX2(A, C) : MAX2(B, C))
+
+#define MIN4( A, B, C, D ) ((A) < (B) ? MIN3(A, C, D) : MIN3(B, C, D))
+#define MAX4( A, B, C, D ) ((A) > (B) ? MAX3(A, C, D) : MAX3(B, C, D))
+
+
+/**
+ * Align a value, only works pot alignemnts.
+ */
+static INLINE int
+align(int value, int alignment)
+{
+ return (value + alignment - 1) & ~(alignment - 1);
+}
+
+/**
+ * Works like align but on npot alignments.
+ */
+static INLINE size_t
+util_align_npot(size_t value, size_t alignment)
+{
+ if (value % alignment)
+ return value + (alignment - (value % alignment));
+ return value;
+}
+
+static INLINE unsigned
+u_minify(unsigned value, unsigned levels)
+{
+ return MAX2(1, value >> levels);
+}
+
+#ifndef COPY_4V
+#define COPY_4V( DST, SRC ) \
+do { \
+ (DST)[0] = (SRC)[0]; \
+ (DST)[1] = (SRC)[1]; \
+ (DST)[2] = (SRC)[2]; \
+ (DST)[3] = (SRC)[3]; \
+} while (0)
+#endif
+
+
+#ifndef COPY_4FV
+#define COPY_4FV( DST, SRC ) COPY_4V(DST, SRC)
+#endif
+
+
+#ifndef ASSIGN_4V
+#define ASSIGN_4V( DST, V0, V1, V2, V3 ) \
+do { \
+ (DST)[0] = (V0); \
+ (DST)[1] = (V1); \
+ (DST)[2] = (V2); \
+ (DST)[3] = (V3); \
+} while (0)
+#endif
+
+
+static INLINE uint32_t util_unsigned_fixed(float value, unsigned frac_bits)
+{
+ return value < 0 ? 0 : (uint32_t)(value * (1<<frac_bits));
+}
+
+static INLINE int32_t util_signed_fixed(float value, unsigned frac_bits)
+{
+ return (int32_t)(value * (1<<frac_bits));
+}
+
+
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* U_MATH_H */
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