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circuitpython/lib/libm/fdlibm.h

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/*
* This file is part of the MicroPython project, http://micropython.org/
*
* This file is adapted from from newlib-nano-2, the newlib/libm/common/fdlib.h,
* available from https://github.com/32bitmicro/newlib-nano-2. The main change
* is removal of anything to do with double precision.
*
* Appropriate copyright headers are reproduced below.
*/
/* @(#)fdlibm.h 5.1 93/09/24 */
/*
* ====================================================
* Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
*
* Developed at SunPro, a Sun Microsystems, Inc. business.
* Permission to use, copy, modify, and distribute this
* software is freely granted, provided that this notice
* is preserved.
* ====================================================
*/
#include <math.h>
/* Default to XOPEN_MODE. */
#define _XOPEN_MODE
/* Most routines need to check whether a float is finite, infinite, or not a
number, and many need to know whether the result of an operation will
overflow. These conditions depend on whether the largest exponent is
used for NaNs & infinities, or whether it's used for finite numbers. The
macros below wrap up that kind of information:
FLT_UWORD_IS_FINITE(X)
True if a positive float with bitmask X is finite.
FLT_UWORD_IS_NAN(X)
True if a positive float with bitmask X is not a number.
FLT_UWORD_IS_INFINITE(X)
True if a positive float with bitmask X is +infinity.
FLT_UWORD_MAX
The bitmask of FLT_MAX.
FLT_UWORD_HALF_MAX
The bitmask of FLT_MAX/2.
FLT_UWORD_EXP_MAX
The bitmask of the largest finite exponent (129 if the largest
exponent is used for finite numbers, 128 otherwise).
FLT_UWORD_LOG_MAX
The bitmask of log(FLT_MAX), rounded down. This value is the largest
input that can be passed to exp() without producing overflow.
FLT_UWORD_LOG_2MAX
The bitmask of log(2*FLT_MAX), rounded down. This value is the
largest input than can be passed to cosh() without producing
overflow.
FLT_LARGEST_EXP
The largest biased exponent that can be used for finite numbers
(255 if the largest exponent is used for finite numbers, 254
otherwise) */
#ifdef _FLT_LARGEST_EXPONENT_IS_NORMAL
#define FLT_UWORD_IS_FINITE(x) 1
#define FLT_UWORD_IS_NAN(x) 0
#define FLT_UWORD_IS_INFINITE(x) 0
#define FLT_UWORD_MAX 0x7fffffff
#define FLT_UWORD_EXP_MAX 0x43010000
#define FLT_UWORD_LOG_MAX 0x42b2d4fc
#define FLT_UWORD_LOG_2MAX 0x42b437e0
#define HUGE ((float)0X1.FFFFFEP128)
#else
#define FLT_UWORD_IS_FINITE(x) ((x)<0x7f800000L)
#define FLT_UWORD_IS_NAN(x) ((x)>0x7f800000L)
#define FLT_UWORD_IS_INFINITE(x) ((x)==0x7f800000L)
#define FLT_UWORD_MAX 0x7f7fffffL
#define FLT_UWORD_EXP_MAX 0x43000000
#define FLT_UWORD_LOG_MAX 0x42b17217
#define FLT_UWORD_LOG_2MAX 0x42b2d4fc
#define HUGE ((float)3.40282346638528860e+38)
#endif
#define FLT_UWORD_HALF_MAX (FLT_UWORD_MAX-(1L<<23))
#define FLT_LARGEST_EXP (FLT_UWORD_MAX>>23)
/* Many routines check for zero and subnormal numbers. Such things depend
on whether the target supports denormals or not:
FLT_UWORD_IS_ZERO(X)
True if a positive float with bitmask X is +0. Without denormals,
any float with a zero exponent is a +0 representation. With
denormals, the only +0 representation is a 0 bitmask.
FLT_UWORD_IS_SUBNORMAL(X)
True if a non-zero positive float with bitmask X is subnormal.
(Routines should check for zeros first.)
FLT_UWORD_MIN
The bitmask of the smallest float above +0. Call this number
REAL_FLT_MIN...
FLT_UWORD_EXP_MIN
The bitmask of the float representation of REAL_FLT_MIN's exponent.
FLT_UWORD_LOG_MIN
The bitmask of |log(REAL_FLT_MIN)|, rounding down.
FLT_SMALLEST_EXP
REAL_FLT_MIN's exponent - EXP_BIAS (1 if denormals are not supported,
-22 if they are).
*/
#ifdef _FLT_NO_DENORMALS
#define FLT_UWORD_IS_ZERO(x) ((x)<0x00800000L)
#define FLT_UWORD_IS_SUBNORMAL(x) 0
#define FLT_UWORD_MIN 0x00800000
#define FLT_UWORD_EXP_MIN 0x42fc0000
#define FLT_UWORD_LOG_MIN 0x42aeac50
#define FLT_SMALLEST_EXP 1
#else
#define FLT_UWORD_IS_ZERO(x) ((x)==0)
#define FLT_UWORD_IS_SUBNORMAL(x) ((x)<0x00800000L)
#define FLT_UWORD_MIN 0x00000001
#define FLT_UWORD_EXP_MIN 0x43160000
#define FLT_UWORD_LOG_MIN 0x42cff1b5
#define FLT_SMALLEST_EXP -22
#endif
#ifdef __STDC__
#undef __P
#define __P(p) p
#else
#define __P(p) ()
#endif
/*
* set X_TLOSS = pi*2**52, which is possibly defined in <values.h>
* (one may replace the following line by "#include <values.h>")
*/
#define X_TLOSS 1.41484755040568800000e+16
/* Functions that are not documented, and are not in <math.h>. */
/* Undocumented float functions. */
#ifdef _SCALB_INT
extern float scalbf __P((float, int));
#else
extern float scalbf __P((float, float));
#endif
extern float significandf __P((float));
/* ieee style elementary float functions */
extern float __ieee754_sqrtf __P((float));
extern float __ieee754_acosf __P((float));
extern float __ieee754_acoshf __P((float));
extern float __ieee754_logf __P((float));
extern float __ieee754_atanhf __P((float));
extern float __ieee754_asinf __P((float));
extern float __ieee754_atan2f __P((float,float));
extern float __ieee754_expf __P((float));
extern float __ieee754_coshf __P((float));
extern float __ieee754_fmodf __P((float,float));
extern float __ieee754_powf __P((float,float));
extern float __ieee754_lgammaf_r __P((float,int *));
extern float __ieee754_gammaf_r __P((float,int *));
extern float __ieee754_log10f __P((float));
extern float __ieee754_sinhf __P((float));
extern float __ieee754_hypotf __P((float,float));
extern float __ieee754_j0f __P((float));
extern float __ieee754_j1f __P((float));
extern float __ieee754_y0f __P((float));
extern float __ieee754_y1f __P((float));
extern float __ieee754_jnf __P((int,float));
extern float __ieee754_ynf __P((int,float));
extern float __ieee754_remainderf __P((float,float));
extern __int32_t __ieee754_rem_pio2f __P((float,float*));
#ifdef _SCALB_INT
extern float __ieee754_scalbf __P((float,int));
#else
extern float __ieee754_scalbf __P((float,float));
#endif
/* float versions of fdlibm kernel functions */
extern float __kernel_sinf __P((float,float,int));
extern float __kernel_cosf __P((float,float));
extern float __kernel_tanf __P((float,float,int));
extern int __kernel_rem_pio2f __P((float*,float*,int,int,int,const __int32_t*));
/* A union which permits us to convert between a float and a 32 bit
int. */
typedef union
{
float value;
__uint32_t word;
} ieee_float_shape_type;
/* Get a 32 bit int from a float. */
#define GET_FLOAT_WORD(i,d) \
do { \
ieee_float_shape_type gf_u; \
gf_u.value = (d); \
(i) = gf_u.word; \
} while (0)
/* Set a float from a 32 bit int. */
#define SET_FLOAT_WORD(d,i) \
do { \
ieee_float_shape_type sf_u; \
sf_u.word = (i); \
(d) = sf_u.value; \
} while (0)
/* Macros to avoid undefined behaviour that can arise if the amount
of a shift is exactly equal to the size of the shifted operand. */
#define SAFE_LEFT_SHIFT(op,amt) \
(((amt) < 8 * sizeof(op)) ? ((op) << (amt)) : 0)
#define SAFE_RIGHT_SHIFT(op,amt) \
(((amt) < 8 * sizeof(op)) ? ((op) >> (amt)) : 0)