std_cmath.h

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// -*- C++ -*- C forwarding header.

// Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003
// Free Software Foundation, Inc.
//
// This file is part of the GNU ISO C++ Library.  This library is free
// software; you can redistribute it and/or modify it under the
// terms of the GNU General Public License as published by the
// Free Software Foundation; either version 2, or (at your option)
// any later version.

// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.

// You should have received a copy of the GNU General Public License along
// with this library; see the file COPYING.  If not, write to the Free
// Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307,
// USA.

// As a special exception, you may use this file as part of a free software
// library without restriction.  Specifically, if other files instantiate
// templates or use macros or inline functions from this file, or you compile
// this file and link it with other files to produce an executable, this
// file does not by itself cause the resulting executable to be covered by
// the GNU General Public License.  This exception does not however
// invalidate any other reasons why the executable file might be covered by
// the GNU General Public License.

//
// ISO C++ 14882: 26.5  C library
//

/** @file cmath
 *  This is a Standard C++ Library file.  You should @c #include this file
 *  in your programs, rather than any of the "*.h" implementation files.
 *
 *  This is the C++ version of the Standard C Library header @c math.h,
 *  and its contents are (mostly) the same as that header, but are all
 *  contained in the namespace @c std.
 */

#ifndef _CPP_CMATH
#define _CPP_CMATH 1

#pragma GCC system_header

#include <bits/c++config.h>

#include <math.h>

// Get rid of those macros defined in <math.h> in lieu of real functions.
#undef abs
#undef div
#undef acos
#undef asin
#undef atan
#undef atan2
#undef ceil
#undef cos
#undef cosh
#undef exp
#undef fabs
#undef floor
#undef fmod
#undef frexp
#undef ldexp
#undef log
#undef log10
#undef modf
#undef pow
#undef sin
#undef sinh
#undef sqrt
#undef tan
#undef tanh

// ...and in the darkness bind them...
namespace __gnu_cxx
{
  namespace  __c99_binding
  {
#if _GLIBCPP_USE_C99_FLOAT_TRANSCENDENTALS_CHECK || \
    _GLIBCPP_USE_C99_FLOAT_TRANSCENDENTALS_DYNAMIC
    extern "C" float (acosf)(float);
    extern "C" float (asinf)(float);
    extern "C" float (atanf)(float);
    extern "C" float (atan2f)(float, float);
    extern "C" float (ceilf)(float);
    extern "C" float (coshf)(float);
    extern "C" float (expf)(float);
    extern "C" float (floorf)(float);
    extern "C" float (fmodf)(float, float);
    extern "C" float (frexpf)(float, int*);
    extern "C" float (ldexpf)(float, int);
    extern "C" float (logf)(float);
    extern "C" float (log10f)(float);
    extern "C" float (modff)(float, float*);
    extern "C" float (powf)(float, float);
    extern "C" float (sinhf)(float);
    extern "C" float (tanf)(float);
    extern "C" float (tanhf)(float);
#endif
#if !_GLIBCPP_USE_C99_FLOAT_TRANSCENDENTALS_DYNAMIC
#if _GLIBCPP_HAVE_ACOSF
    using ::acosf;
#endif
#if _GLIBCPP_HAVE_ASINF
    using ::asinf;
#endif
#if _GLIBCPP_HAVE_ATANF
    using ::atanf;
#endif
#if _GLIBCPP_HAVE_ATAN2F
    using ::atan2f;
#endif
#if _GLIBCPP_HAVE_CEILF
    using ::ceilf;
#endif
#if _GLIBCPP_HAVE_COSHF
    using ::coshf;
#endif
#if _GLIBCPP_HAVE_EXPF
    using ::expf;
#endif
#if _GLIBCPP_HAVE_FLOORF
    using ::floorf;
#endif
#if _GLIBCPP_HAVE_FMODF
    using ::fmodf;
#endif
#if _GLIBCPP_HAVE_FREXPF
    using ::frexpf;
#endif
#if _GLIBCPP_HAVE_LDEXPF
    using ::ldexpf;
#endif
#if _GLIBCPP_HAVE_LOGF
    using ::logf;
#endif
#if _GLIBCPP_HAVE_LOG10F
    using ::log10f;
#endif
#if _GLIBCPP_HAVE_MODFF
    using ::modff;
#endif
#if _GLIBCPP_HAVE_POWF
    using ::powf;
#endif
#if _GLIBCPP_HAVE_SINHF
    using ::sinhf;
#endif
#if _GLIBCPP_HAVE_TANF
    using ::tanf;
#endif
#if _GLIBCPP_HAVE_TANHF
    using ::tanhf;
#endif
#endif /* _GLIBCPP_USE_C99_FLOAT_TRANSCENDENTALS_DYNAMIC */
  }
}

namespace std 
{
  // Forward declaration of a helper function.  This really should be
  // an `exported' forward declaration.
  template<typename _Tp> _Tp __cmath_power(_Tp, unsigned int);

  inline double
  abs(double __x)
  { return __builtin_fabs(__x); }

  inline float
  abs(float __x)
  { return __builtin_fabsf(__x); }

  inline long double
  abs(long double __x)
  { return __builtin_fabsl(__x); }

#if _GLIBCPP_HAVE_ACOSF
  inline float 
  acos(float __x) { return __gnu_cxx::__c99_binding::acosf(__x); }
#else
  inline float 
  acos(float __x) { return ::acos(static_cast<double>(__x)); }
#endif

  using ::acos;
  
#if _GLIBCPP_HAVE_ACOSL
  inline long double 
  acos(long double __x) { return ::acosl(__x); }
#else
  inline long double 
  acos(long double __x) { return ::acos(static_cast<double>(__x)); }
#endif

  using ::asin;

#if _GLIBCPP_HAVE_ASINF
  inline float 
  asin(float __x) { return __gnu_cxx::__c99_binding::asinf(__x); }
#else
  inline float 
  asin(float __x) { return ::asin(static_cast<double>(__x)); }
#endif

#if _GLIBCPP_HAVE_ASINL
  inline long double 
  asin(long double __x) { return ::asinl(__x); }
#else
  inline long double 
  asin(long double __x) { return ::asin(static_cast<double>(__x)); }
#endif

  using ::atan;

#if _GLIBCPP_HAVE_ATANF
  inline float 
  atan(float __x) { return __gnu_cxx::__c99_binding::atanf(__x); }
#else
  inline float 
  atan(float __x) { return ::atan(static_cast<double>(__x)); }
#endif

#if _GLIBCPP_HAVE_ATANL
  inline long double 
  atan(long double __x) { return ::atanl(__x); }
#else
  inline long double 
  atan(long double __x) { return ::atan(static_cast<double>(__x)); }
#endif

  using ::atan2;

#if _GLIBCPP_HAVE_ATAN2F
  inline float 
  atan2(float __y, float __x) { return __gnu_cxx::__c99_binding::atan2f(__y, __x); }
#else
  inline float 
  atan2(float __y, float __x)
  { return ::atan2(static_cast<double>(__y), static_cast<double>(__x)); }
#endif

#if _GLIBCPP_HAVE_ATAN2L
  inline long double 
  atan2(long double __y, long double __x) { return ::atan2l(__y, __x); }
#else
  inline long double 
  atan2(long double __y, long double __x) 
  { return ::atan2(static_cast<double>(__y), static_cast<double>(__x)); }
#endif

  using ::ceil;

#if _GLIBCPP_HAVE_CEILF
  inline float 
  ceil(float __x) { return __gnu_cxx::__c99_binding::ceilf(__x); }
#else
  inline float 
  ceil(float __x) { return ::ceil(static_cast<double>(__x)); }
#endif

#if _GLIBCPP_HAVE_CEILL
  inline long double 
  ceil(long double __x) { return ::ceill(__x); }
#else
  inline long double 
  ceil(long double __x) { return ::ceil(static_cast<double>(__x)); }
#endif

  using ::cos;

  inline float
  cos(float __x)
  { return __builtin_cosf(__x); }

  inline long double
  cos(long double __x)
  { return __builtin_cosl(__x); }

  using ::cosh;

#if _GLIBCPP_HAVE_COSHF
  inline float 
  cosh(float __x) { return __gnu_cxx::__c99_binding::coshf(__x); }
#else
  inline float 
  cosh(float __x) { return ::cosh(static_cast<double>(__x)); }
#endif

#if _GLIBCPP_HAVE_COSHL
  inline long double 
  cosh(long double __x) { return ::coshl(__x); }
#else
  inline long double 
  cosh(long double __x) { return ::cosh(static_cast<double>(__x)); }
#endif

  using ::exp;

#if _GLIBCPP_HAVE_EXPF
  inline float 
  exp(float __x) { return __gnu_cxx::__c99_binding::expf(__x); }
#else
  inline float 
  exp(float __x) { return ::exp(static_cast<double>(__x)); }
#endif

#if _GLIBCPP_HAVE_EXPL
  inline long double 
  exp(long double __x) { return ::expl(__x); }
#else
  inline long double 
  exp(long double __x) { return ::exp(static_cast<double>(__x)); }
#endif

  using ::fabs;

  inline float
  fabs(float __x)
  { return __builtin_fabsf(__x); }

  inline long double
  fabs(long double __x)
  { return __builtin_fabsl(__x); }

  using ::floor;

#if _GLIBCPP_HAVE_FLOORF
  inline float 
  floor(float __x) { return __gnu_cxx::__c99_binding::floorf(__x); }
#else
  inline float 
  floor(float __x) { return ::floor(static_cast<double>(__x)); }
#endif

#if _GLIBCPP_HAVE_FLOORL
  inline long double 
  floor(long double __x) { return ::floorl(__x); }
#else
  inline long double 
  floor(long double __x) { return ::floor(static_cast<double>(__x)); }
#endif

  using ::fmod;

#if _GLIBCPP_HAVE_FMODF
  inline float 
  fmod(float __x, float __y) { return __gnu_cxx::__c99_binding::fmodf(__x, __y); }
#else
  inline float 
  fmod(float __x, float __y)
  { return ::fmod(static_cast<double>(__x), static_cast<double>(__y)); }
#endif

#if _GLIBCPP_HAVE_FMODL
  inline long double 
  fmod(long double __x, long double __y) { return ::fmodl(__x, __y); }
#else
  inline long double 
  fmod(long double __x, long double __y) 
  { return ::fmod(static_cast<double>(__x), static_cast<double>(__y)); }
#endif

  using ::frexp;

#if _GLIBCPP_HAVE_FREXPF
  inline float 
  frexp(float __x, int* __exp) { return __gnu_cxx::__c99_binding::frexpf(__x, __exp); }
#else
  inline float