4
#include "pyconfig.h" /* include for defines */
6
/**************************************************************************
7
Symbols and macros to supply platform-independent interfaces to mathematical
8
functions and constants
9
**************************************************************************/
11
/* Python provides implementations for copysign, round and hypot in
12
* Python/pymath.c just in case your math library doesn't provide the
15
*Note: PC/pyconfig.h defines copysign as _copysign
18
extern double copysign(double, double);
22
extern double round(double);
26
extern double hypot(double, double);
29
/* extra declarations */
32
extern double fmod (double, double);
33
extern double frexp (double, int *);
34
extern double ldexp (double, int);
35
extern double modf (double, double *);
36
extern double pow(double, double);
40
/* High precision defintion of pi and e (Euler)
41
* The values are taken from libc6's math.h.
44
#define Py_MATH_PIl 3.1415926535897932384626433832795029L
47
#define Py_MATH_PI 3.14159265358979323846
51
#define Py_MATH_El 2.7182818284590452353602874713526625L
55
#define Py_MATH_E 2.7182818284590452354
58
/* On x86, Py_FORCE_DOUBLE forces a floating-point number out of an x87 FPU
59
register and into a 64-bit memory location, rounding from extended
60
precision to double precision in the process. On other platforms it does
63
/* we take double rounding as evidence of x87 usage */
64
#ifndef Py_LIMITED_API
65
#ifndef Py_FORCE_DOUBLE
66
# ifdef X87_DOUBLE_ROUNDING
67
PyAPI_FUNC(double) _Py_force_double(double);
68
# define Py_FORCE_DOUBLE(X) (_Py_force_double(X))
70
# define Py_FORCE_DOUBLE(X) (X)
75
#ifndef Py_LIMITED_API
76
#ifdef HAVE_GCC_ASM_FOR_X87
77
PyAPI_FUNC(unsigned short) _Py_get_387controlword(void);
78
PyAPI_FUNC(void) _Py_set_387controlword(unsigned short);
83
* Return 1 if float or double arg is a NaN, else 0.
85
* X is evaluated more than once.
86
* This may not work on all platforms. Each platform has *some*
87
* way to spell this, though -- override in pyconfig.h if you have
88
* a platform where it doesn't work.
89
* Note: PC/pyconfig.h defines Py_IS_NAN as _isnan
92
#if defined HAVE_DECL_ISNAN && HAVE_DECL_ISNAN == 1
93
#define Py_IS_NAN(X) isnan(X)
95
#define Py_IS_NAN(X) ((X) != (X))
100
* Return 1 if float or double arg is an infinity, else 0.
102
* X is evaluated more than once.
103
* This implementation may set the underflow flag if |X| is very small;
104
* it really can't be implemented correctly (& easily) before C99.
105
* Override in pyconfig.h if you have a better spelling on your platform.
106
* Py_FORCE_DOUBLE is used to avoid getting false negatives from a
107
* non-infinite value v sitting in an 80-bit x87 register such that
108
* v becomes infinite when spilled from the register to 64-bit memory.
109
* Note: PC/pyconfig.h defines Py_IS_INFINITY as _isinf
111
#ifndef Py_IS_INFINITY
112
# if defined HAVE_DECL_ISINF && HAVE_DECL_ISINF == 1
113
# define Py_IS_INFINITY(X) isinf(X)
115
# define Py_IS_INFINITY(X) ((X) && \
116
(Py_FORCE_DOUBLE(X)*0.5 == Py_FORCE_DOUBLE(X)))
121
* Return 1 if float or double arg is neither infinite nor NAN, else 0.
122
* Some compilers (e.g. VisualStudio) have intrisics for this, so a special
123
* macro for this particular test is useful
124
* Note: PC/pyconfig.h defines Py_IS_FINITE as _finite
127
#if defined HAVE_DECL_ISFINITE && HAVE_DECL_ISFINITE == 1
128
#define Py_IS_FINITE(X) isfinite(X)
129
#elif defined HAVE_FINITE
130
#define Py_IS_FINITE(X) finite(X)
132
#define Py_IS_FINITE(X) (!Py_IS_INFINITY(X) && !Py_IS_NAN(X))
136
/* HUGE_VAL is supposed to expand to a positive double infinity. Python
137
* uses Py_HUGE_VAL instead because some platforms are broken in this
138
* respect. We used to embed code in pyport.h to try to worm around that,
139
* but different platforms are broken in conflicting ways. If you're on
140
* a platform where HUGE_VAL is defined incorrectly, fiddle your Python
141
* config to #define Py_HUGE_VAL to something that works on your platform.
144
#define Py_HUGE_VAL HUGE_VAL
148
* A value that evaluates to a NaN. On IEEE 754 platforms INF*0 or
149
* INF/INF works. Define Py_NO_NAN in pyconfig.h if your platform
150
* doesn't support NaNs.
152
#if !defined(Py_NAN) && !defined(Py_NO_NAN)
153
#if !defined(__INTEL_COMPILER)
154
#define Py_NAN (Py_HUGE_VAL * 0.)
155
#else /* __INTEL_COMPILER */
156
#if defined(ICC_NAN_STRICT)
157
#pragma float_control(push)
158
#pragma float_control(precise, on)
159
#pragma float_control(except, on)
160
#if defined(_MSC_VER)
163
__attribute__((noinline))
164
#endif /* _MSC_VER */
165
static double __icc_nan()
169
#pragma float_control (pop)
170
#define Py_NAN __icc_nan()
171
#else /* ICC_NAN_RELAXED as default for Intel Compiler */
172
static union { unsigned char buf[8]; double __icc_nan; } __nan_store = {0,0,0,0,0,0,0xf8,0x7f};
173
#define Py_NAN (__nan_store.__icc_nan)
174
#endif /* ICC_NAN_STRICT */
175
#endif /* __INTEL_COMPILER */
179
* Return 1 iff a libm function overflowed. Set errno to 0 before calling
180
* a libm function, and invoke this macro after, passing the function
183
* This isn't reliable. C99 no longer requires libm to set errno under
184
* any exceptional condition, but does require +- HUGE_VAL return
185
* values on overflow. A 754 box *probably* maps HUGE_VAL to a
186
* double infinity, and we're cool if that's so, unless the input
187
* was an infinity and an infinity is the expected result. A C89
188
* system sets errno to ERANGE, so we check for that too. We're
189
* out of luck if a C99 754 box doesn't map HUGE_VAL to +Inf, or
190
* if the returned result is a NaN, or if a C89 box returns HUGE_VAL
191
* in non-overflow cases.
192
* X is evaluated more than once.
193
* Some platforms have better way to spell this, so expect some #ifdef'ery.
195
* OpenBSD uses 'isinf()' because a compiler bug on that platform causes
196
* the longer macro version to be mis-compiled. This isn't optimal, and
197
* should be removed once a newer compiler is available on that platform.
198
* The system that had the failure was running OpenBSD 3.2 on Intel, with
201
* According to Tim's checkin, the FreeBSD systems use isinf() to work
202
* around a FPE bug on that platform.
204
#if defined(__FreeBSD__) || defined(__OpenBSD__)
205
#define Py_OVERFLOWED(X) isinf(X)
207
#define Py_OVERFLOWED(X) ((X) != 0.0 && (errno == ERANGE || \
208
(X) == Py_HUGE_VAL || \
209
(X) == -Py_HUGE_VAL))
212
#endif /* Py_PYMATH_H */