1 /* Declarations for math functions.
2 Copyright (C) 1991-1993, 1995-1999, 2001, 2002, 2004, 2006
3 Free Software Foundation, Inc.
4 This file is part of the GNU C Library.
6 The GNU C Library is free software; you can redistribute it and/or
7 modify it under the terms of the GNU Lesser General Public
8 License as published by the Free Software Foundation; either
9 version 2.1 of the License, or (at your option) any later version.
11 The GNU C Library is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 Lesser General Public License for more details.
16 You should have received a copy of the GNU Lesser General Public
17 License along with the GNU C Library; if not, write to the Free
18 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
22 * ISO C99 Standard: 7.12 Mathematics <math.h>
32 /* Get machine-dependent HUGE_VAL value (returned on overflow).
33 On all IEEE754 machines, this is +Infinity. */
34 #include <bits/huge_val.h>
36 # include <bits/huge_valf.h>
37 # include <bits/huge_vall.h>
39 /* Get machine-dependent INFINITY value. */
40 # include <bits/inf.h>
42 /* Get machine-dependent NAN value (returned for some domain errors). */
43 # include <bits/nan.h>
44 #endif /* __USE_ISOC99 */
46 /* Get general and ISO C99 specific information. */
47 #include <bits/mathdef.h>
50 /* The file <bits/mathcalls.h> contains the prototypes for all the
51 actual math functions. These macros are used for those prototypes,
52 so we can easily declare each function as both `name' and `__name',
53 and can declare the float versions `namef' and `__namef'. */
55 #define __MATHCALL(function,suffix, args) \
56 __MATHDECL (_Mdouble_,function,suffix, args)
57 #define __MATHDECL(type, function,suffix, args) \
58 __MATHDECL_1(type, function,suffix, args);
60 #define __MATHCALLX(function,suffix, args, attrib) \
61 __MATHDECLX (_Mdouble_,function,suffix, args, attrib)
62 #define __MATHDECL_1(type, function,suffix, args) \
63 extern type __MATH_PRECNAME(function,suffix) args __THROW
64 #define __MATHDECLX(type, function,suffix, args, attrib) \
65 __MATHDECL_1(type, function,suffix, args) __attribute__ (attrib); \
66 __MATHDECLI_MAINVARIANT(function)
68 /* Decls which are also used internally in libm.
69 Only the main variant is used internally, no need to try to avoid relocs
70 for the {l,f} variants. */
71 #define __MATHCALLI(function,suffix, args) \
72 __MATHDECLI (_Mdouble_,function,suffix, args)
73 #define __MATHDECLI(type, function,suffix, args) \
74 __MATHDECL_1(type, function,suffix, args); \
75 __MATHDECLI_MAINVARIANT(function)
76 /* Private helpers for purely macro impls below.
77 Only make __foo{,f,l} visible but not (the macro-only) foo. */
79 # define __MATHDECL_PRIV(type, function,suffix, args, attrib) \
80 __MATHDECL_1(type, __CONCAT(__,function),suffix, args) __attribute__ (attrib); \
81 libm_hidden_proto(__MATH_PRECNAME(__##function,suffix))
83 # define __MATHDECL_PRIV(type, function,suffix, args, attrib) \
84 __MATHDECL_1(type, __CONCAT(__,function),suffix, args) __attribute__ (attrib);
88 # define __MATHDECLI_MAINVARIANT(x) libm_hidden_proto(x)
90 # define __MATHDECLI_MAINVARIANT(x)
92 #define _Mdouble_ double
93 #define __MATH_PRECNAME(name,r) __CONCAT(name,r)
94 #define _Mdouble_BEGIN_NAMESPACE __BEGIN_NAMESPACE_STD
95 #define _Mdouble_END_NAMESPACE __END_NAMESPACE_STD
96 #include <bits/mathcalls.h>
98 #undef _Mdouble_BEGIN_NAMESPACE
99 #undef _Mdouble_END_NAMESPACE
100 #undef __MATH_PRECNAME
101 #undef __MATHDECLI_MAINVARIANT
102 #define __MATHDECLI_MAINVARIANT(x)
105 #if defined __USE_MISC || defined __USE_ISOC99
107 /* Include the file of declarations again, this time using `float'
108 instead of `double' and appending f to each function name. */
111 # define _Mfloat_ float
113 # define _Mdouble_ _Mfloat_
115 # define __MATH_PRECNAME(name,r) name##f##r
117 # define __MATH_PRECNAME(name,r) name/**/f/**/r
119 # define _Mdouble_BEGIN_NAMESPACE __BEGIN_NAMESPACE_C99
120 # define _Mdouble_END_NAMESPACE __END_NAMESPACE_C99
121 # include <bits/mathcalls.h>
123 # undef _Mdouble_BEGIN_NAMESPACE
124 # undef _Mdouble_END_NAMESPACE
125 # undef __MATH_PRECNAME
127 # if (__STDC__ - 0 || __GNUC__ - 0) \
128 && (defined __UCLIBC_HAS_LONG_DOUBLE_MATH__ || defined __LDBL_COMPAT)
129 # ifdef __LDBL_COMPAT
132 extern float __nldbl_nexttowardf (float __x, long double __y)
133 __THROW __attribute__ ((__const__));
134 # ifdef __REDIRECT_NTH
135 extern float __REDIRECT_NTH (nexttowardf, (float __x, long double __y),
137 __attribute__ ((__const__));
138 extern double __REDIRECT_NTH (nexttoward, (double __x, long double __y),
139 nextafter) __attribute__ ((__const__));
140 extern long double __REDIRECT_NTH (nexttowardl,
141 (long double __x, long double __y),
142 nextafter) __attribute__ ((__const__));
146 /* Include the file of declarations again, this time using `long double'
147 instead of `double' and appending l to each function name. */
150 # define __MATHDECL_2(type, function,suffix, args, alias) \
151 extern type __REDIRECT_NTH(__MATH_PRECNAME(function,suffix), \
153 # define __MATHDECL_1(type, function,suffix, args) \
154 __MATHDECL_2(type, function,suffix, args, __CONCAT(function,suffix))
157 # ifndef _Mlong_double_
158 # define _Mlong_double_ long double
160 # define _Mdouble_ _Mlong_double_
162 # define __MATH_PRECNAME(name,r) name##l##r
164 # define __MATH_PRECNAME(name,r) name/**/l/**/r
166 # define _Mdouble_BEGIN_NAMESPACE __BEGIN_NAMESPACE_C99
167 # define _Mdouble_END_NAMESPACE __END_NAMESPACE_C99
168 # include <bits/mathcalls.h>
170 # undef _Mdouble_BEGIN_NAMESPACE
171 # undef _Mdouble_END_NAMESPACE
172 # undef __MATH_PRECNAME
174 # endif /* __STDC__ || __GNUC__ */
176 #endif /* Use misc or ISO C99. */
182 #if defined __USE_MISC || defined __USE_XOPEN
183 /* This variable is used by `gamma' and `lgamma'. */
185 libm_hidden_proto(signgam)
189 /* ISO C99 defines some generic macros which work on any data type. */
192 /* Get the architecture specific values describing the floating-point
193 evaluation. The following symbols will get defined:
195 float_t floating-point type at least as wide as `float' used
196 to evaluate `float' expressions
197 double_t floating-point type at least as wide as `double' used
198 to evaluate `double' expressions
202 0 if `float_t' is `float' and `double_t' is `double'
203 1 if `float_t' and `double_t' are `double'
204 2 if `float_t' and `double_t' are `long double'
205 else `float_t' and `double_t' are unspecified
207 INFINITY representation of the infinity value of type `float'
212 If defined it indicates that the `fma' function
213 generally executes about as fast as a multiply and an add.
214 This macro is defined only iff the `fma' function is
215 implemented directly with a hardware multiply-add instructions.
217 FP_ILOGB0 Expands to a value returned by `ilogb (0.0)'.
218 FP_ILOGBNAN Expands to a value returned by `ilogb (NAN)'.
220 DECIMAL_DIG Number of decimal digits supported by conversion between
221 decimal and all internal floating-point formats.
225 /* All floating-point numbers can be put in one of these categories. */
229 # define FP_NAN FP_NAN
231 # define FP_INFINITE FP_INFINITE
233 # define FP_ZERO FP_ZERO
235 # define FP_SUBNORMAL FP_SUBNORMAL
237 # define FP_NORMAL FP_NORMAL
240 /* Return number of classification appropriate for X. */
241 # ifndef __UCLIBC_HAS_LONG_DOUBLE_MATH__
242 # define fpclassify(x) \
243 (sizeof (x) == sizeof (float) ? __fpclassifyf (x) : __fpclassify (x))
245 # define fpclassify(x) \
246 (sizeof (x) == sizeof (float) \
247 ? __fpclassifyf (x) \
248 : sizeof (x) == sizeof (double) \
249 ? __fpclassify (x) : __fpclassifyl (x))
252 /* Return nonzero value if sign of X is negative. */
253 # ifndef __UCLIBC_HAS_LONG_DOUBLE_MATH__
254 # define signbit(x) \
255 (sizeof (x) == sizeof (float) ? __signbitf (x) : __signbit (x))
257 # define signbit(x) \
258 (sizeof (x) == sizeof (float) \
260 : sizeof (x) == sizeof (double) \
261 ? __signbit (x) : __signbitl (x))
264 /* Return nonzero value if X is not +-Inf or NaN. */
265 # ifndef __UCLIBC_HAS_LONG_DOUBLE_MATH__
266 # define isfinite(x) \
267 (sizeof (x) == sizeof (float) ? __finitef (x) : __finite (x))
269 # define isfinite(x) \
270 (sizeof (x) == sizeof (float) \
272 : sizeof (x) == sizeof (double) \
273 ? __finite (x) : __finitel (x))
276 /* Return nonzero value if X is neither zero, subnormal, Inf, nor NaN. */
277 # define isnormal(x) (fpclassify (x) == FP_NORMAL)
279 /* Return nonzero value if X is a NaN. We could use `fpclassify' but
280 we already have this functions `__isnan' and it is faster. */
281 # ifndef __UCLIBC_HAS_LONG_DOUBLE_MATH__
283 (sizeof (x) == sizeof (float) ? __isnanf (x) : __isnan (x))
286 (sizeof (x) == sizeof (float) \
288 : sizeof (x) == sizeof (double) \
289 ? __isnan (x) : __isnanl (x))
292 /* Return nonzero value is X is positive or negative infinity. */
293 # ifndef __UCLIBC_HAS_LONG_DOUBLE_MATH__
295 (sizeof (x) == sizeof (float) ? __isinff (x) : __isinf (x))
298 (sizeof (x) == sizeof (float) \
300 : sizeof (x) == sizeof (double) \
301 ? __isinf (x) : __isinfl (x))
304 /* Bitmasks for the math_errhandling macro. */
305 # define MATH_ERRNO 1 /* errno set by math functions. */
306 # define MATH_ERREXCEPT 2 /* Exceptions raised by math functions. */
308 #endif /* Use ISO C99. */
311 /* Support for various different standard error handling behaviors. */
314 _IEEE_ = -1, /* According to IEEE 754/IEEE 854. */
315 _SVID_, /* According to System V, release 4. */
316 _XOPEN_, /* Nowadays also Unix98. */
318 _ISOC_ /* Actually this is ISO C99. */
321 /* This variable can be changed at run-time to any of the values above to
322 affect floating point error handling behavior (it may also be necessary
323 to change the hardware FPU exception settings). */
324 extern _LIB_VERSION_TYPE _LIB_VERSION;
329 /* In SVID error handling, `matherr' is called with this description
330 of the exceptional condition.
332 We have a problem when using C++ since `exception' is a reserved
348 extern int matherr (struct __exception *__exc) throw ();
350 extern int matherr (struct exception *__exc);
353 # define X_TLOSS 1.41484755040568800000e+16
355 /* Types of exceptions in the `type' field. */
363 /* SVID mode specifies returning this large value instead of infinity. */
364 # define HUGE 3.40282347e+38F
369 /* X/Open wants another strange constant. */
370 # define MAXFLOAT 3.40282347e+38F
376 /* Some useful constants. */
377 #if defined __USE_BSD || defined __USE_XOPEN
378 # define M_E 2.7182818284590452354 /* e */
379 # define M_LOG2E 1.4426950408889634074 /* log_2 e */
380 # define M_LOG10E 0.43429448190325182765 /* log_10 e */
381 # define M_LN2 0.69314718055994530942 /* log_e 2 */
382 # define M_LN10 2.30258509299404568402 /* log_e 10 */
383 # define M_PI 3.14159265358979323846 /* pi */
384 # define M_PI_2 1.57079632679489661923 /* pi/2 */
385 # define M_PI_4 0.78539816339744830962 /* pi/4 */
386 # define M_1_PI 0.31830988618379067154 /* 1/pi */
387 # define M_2_PI 0.63661977236758134308 /* 2/pi */
388 # define M_2_SQRTPI 1.12837916709551257390 /* 2/sqrt(pi) */
389 # define M_SQRT2 1.41421356237309504880 /* sqrt(2) */
390 # define M_SQRT1_2 0.70710678118654752440 /* 1/sqrt(2) */
393 /* The above constants are not adequate for computation using `long double's.
394 Therefore we provide as an extension constants with similar names as a
395 GNU extension. Provide enough digits for the 128-bit IEEE quad. */
397 # define M_El 2.7182818284590452353602874713526625L /* e */
398 # define M_LOG2El 1.4426950408889634073599246810018921L /* log_2 e */
399 # define M_LOG10El 0.4342944819032518276511289189166051L /* log_10 e */
400 # define M_LN2l 0.6931471805599453094172321214581766L /* log_e 2 */
401 # define M_LN10l 2.3025850929940456840179914546843642L /* log_e 10 */
402 # define M_PIl 3.1415926535897932384626433832795029L /* pi */
403 # define M_PI_2l 1.5707963267948966192313216916397514L /* pi/2 */
404 # define M_PI_4l 0.7853981633974483096156608458198757L /* pi/4 */
405 # define M_1_PIl 0.3183098861837906715377675267450287L /* 1/pi */
406 # define M_2_PIl 0.6366197723675813430755350534900574L /* 2/pi */
407 # define M_2_SQRTPIl 1.1283791670955125738961589031215452L /* 2/sqrt(pi) */
408 # define M_SQRT2l 1.4142135623730950488016887242096981L /* sqrt(2) */
409 # define M_SQRT1_2l 0.7071067811865475244008443621048490L /* 1/sqrt(2) */
413 /* When compiling in strict ISO C compatible mode we must not use the
414 inline functions since they, among other things, do not set the
415 `errno' variable correctly. */
416 #if defined __STRICT_ANSI__ && !defined __NO_MATH_INLINES
417 # define __NO_MATH_INLINES 1
420 #if defined __USE_ISOC99 && __GNUC_PREREQ(2,97)
421 /* ISO C99 defines some macros to compare number while taking care for
422 unordered numbers. Many FPUs provide special instructions to support
423 these operations. Generic support in GCC for these as builtins went
424 in before 3.0.0, but not all cpus added their patterns. We define
425 versions that use the builtins here, and <bits/mathinline.h> will
426 undef/redefine as appropriate for the specific GCC version in use. */
427 # define isgreater(x, y) __builtin_isgreater(x, y)
428 # define isgreaterequal(x, y) __builtin_isgreaterequal(x, y)
429 # define isless(x, y) __builtin_isless(x, y)
430 # define islessequal(x, y) __builtin_islessequal(x, y)
431 # define islessgreater(x, y) __builtin_islessgreater(x, y)
432 # define isunordered(u, v) __builtin_isunordered(u, v)
435 /* Get machine-dependent inline versions (if there are any). */
436 #ifdef __USE_EXTERN_INLINES
437 # include <bits/mathinline.h>
441 /* If we've still got undefined comparison macros, provide defaults. */
443 /* Return nonzero value if X is greater than Y. */
445 # define isgreater(x, y) \
447 ({ __typeof__(x) __x = (x); __typeof__(y) __y = (y); \
448 !isunordered (__x, __y) && __x > __y; }))
451 /* Return nonzero value if X is greater than or equal to Y. */
452 # ifndef isgreaterequal
453 # define isgreaterequal(x, y) \
455 ({ __typeof__(x) __x = (x); __typeof__(y) __y = (y); \
456 !isunordered (__x, __y) && __x >= __y; }))
459 /* Return nonzero value if X is less than Y. */
461 # define isless(x, y) \
463 ({ __typeof__(x) __x = (x); __typeof__(y) __y = (y); \
464 !isunordered (__x, __y) && __x < __y; }))
467 /* Return nonzero value if X is less than or equal to Y. */
469 # define islessequal(x, y) \
471 ({ __typeof__(x) __x = (x); __typeof__(y) __y = (y); \
472 !isunordered (__x, __y) && __x <= __y; }))
475 /* Return nonzero value if either X is less than Y or Y is less than X. */
476 # ifndef islessgreater
477 # define islessgreater(x, y) \
479 ({ __typeof__(x) __x = (x); __typeof__(y) __y = (y); \
480 !isunordered (__x, __y) && (__x < __y || __y < __x); }))
483 /* Return nonzero value if arguments are unordered. */
485 # define isunordered(u, v) \
487 ({ __typeof__(u) __u = (u); __typeof__(v) __v = (v); \
488 fpclassify (__u) == FP_NAN || fpclassify (__v) == FP_NAN; }))