newlib-cygwin/newlib/libm/common/fdlibm.h

405 lines
12 KiB
C

/* @(#)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.
* ====================================================
*/
/* REDHAT LOCAL: Include files. */
#include <math.h>
#include <sys/types.h>
#include <machine/ieeefp.h>
/* REDHAT LOCAL: 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>. */
#ifdef _SCALB_INT
extern double scalb __P((double, int));
#else
extern double scalb __P((double, double));
#endif
extern double significand __P((double));
/* ieee style elementary functions */
extern double __ieee754_sqrt __P((double));
extern double __ieee754_acos __P((double));
extern double __ieee754_acosh __P((double));
extern double __ieee754_log __P((double));
extern double __ieee754_atanh __P((double));
extern double __ieee754_asin __P((double));
extern double __ieee754_atan2 __P((double,double));
extern double __ieee754_exp __P((double));
extern double __ieee754_cosh __P((double));
extern double __ieee754_fmod __P((double,double));
extern double __ieee754_pow __P((double,double));
extern double __ieee754_lgamma_r __P((double,int *));
extern double __ieee754_gamma_r __P((double,int *));
extern double __ieee754_log10 __P((double));
extern double __ieee754_sinh __P((double));
extern double __ieee754_hypot __P((double,double));
extern double __ieee754_j0 __P((double));
extern double __ieee754_j1 __P((double));
extern double __ieee754_y0 __P((double));
extern double __ieee754_y1 __P((double));
extern double __ieee754_jn __P((int,double));
extern double __ieee754_yn __P((int,double));
extern double __ieee754_remainder __P((double,double));
extern __int32_t __ieee754_rem_pio2 __P((double,double*));
#ifdef _SCALB_INT
extern double __ieee754_scalb __P((double,int));
#else
extern double __ieee754_scalb __P((double,double));
#endif
/* fdlibm kernel function */
extern double __kernel_standard __P((double,double,int));
extern double __kernel_sin __P((double,double,int));
extern double __kernel_cos __P((double,double));
extern double __kernel_tan __P((double,double,int));
extern int __kernel_rem_pio2 __P((double*,double*,int,int,int,const __int32_t*));
/* 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*));
/* The original code used statements like
n0 = ((*(int*)&one)>>29)^1; * index of high word *
ix0 = *(n0+(int*)&x); * high word of x *
ix1 = *((1-n0)+(int*)&x); * low word of x *
to dig two 32 bit words out of the 64 bit IEEE floating point
value. That is non-ANSI, and, moreover, the gcc instruction
scheduler gets it wrong. We instead use the following macros.
Unlike the original code, we determine the endianness at compile
time, not at run time; I don't see much benefit to selecting
endianness at run time. */
#ifndef __IEEE_BIG_ENDIAN
#ifndef __IEEE_LITTLE_ENDIAN
#error Must define endianness
#endif
#endif
/* A union which permits us to convert between a double and two 32 bit
ints. */
#ifdef __IEEE_BIG_ENDIAN
typedef union
{
double value;
struct
{
__uint32_t msw;
__uint32_t lsw;
} parts;
} ieee_double_shape_type;
#endif
#ifdef __IEEE_LITTLE_ENDIAN
typedef union
{
double value;
struct
{
__uint32_t lsw;
__uint32_t msw;
} parts;
} ieee_double_shape_type;
#endif
/* Get two 32 bit ints from a double. */
#define EXTRACT_WORDS(ix0,ix1,d) \
do { \
ieee_double_shape_type ew_u; \
ew_u.value = (d); \
(ix0) = ew_u.parts.msw; \
(ix1) = ew_u.parts.lsw; \
} while (0)
/* Get the more significant 32 bit int from a double. */
#define GET_HIGH_WORD(i,d) \
do { \
ieee_double_shape_type gh_u; \
gh_u.value = (d); \
(i) = gh_u.parts.msw; \
} while (0)
/* Get the less significant 32 bit int from a double. */
#define GET_LOW_WORD(i,d) \
do { \
ieee_double_shape_type gl_u; \
gl_u.value = (d); \
(i) = gl_u.parts.lsw; \
} while (0)
/* Set a double from two 32 bit ints. */
#define INSERT_WORDS(d,ix0,ix1) \
do { \
ieee_double_shape_type iw_u; \
iw_u.parts.msw = (ix0); \
iw_u.parts.lsw = (ix1); \
(d) = iw_u.value; \
} while (0)
/* Set the more significant 32 bits of a double from an int. */
#define SET_HIGH_WORD(d,v) \
do { \
ieee_double_shape_type sh_u; \
sh_u.value = (d); \
sh_u.parts.msw = (v); \
(d) = sh_u.value; \
} while (0)
/* Set the less significant 32 bits of a double from an int. */
#define SET_LOW_WORD(d,v) \
do { \
ieee_double_shape_type sl_u; \
sl_u.value = (d); \
sl_u.parts.lsw = (v); \
(d) = sl_u.value; \
} while (0)
/* 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)
#ifdef _COMPLEX_H
/*
* Quoting from ISO/IEC 9899:TC2:
*
* 6.2.5.13 Types
* Each complex type has the same representation and alignment requirements as
* an array type containing exactly two elements of the corresponding real type;
* the first element is equal to the real part, and the second element to the
* imaginary part, of the complex number.
*/
typedef union {
float complex z;
float parts[2];
} float_complex;
typedef union {
double complex z;
double parts[2];
} double_complex;
typedef union {
long double complex z;
long double parts[2];
} long_double_complex;
#define REAL_PART(z) ((z).parts[0])
#define IMAG_PART(z) ((z).parts[1])
#endif /* _COMPLEX_H */