gcc/libstdc++-v3/src/cmath.cc
Benjamin Kosnik b2dad0e372 libstdc++-v3: New directory.
2000-04-21  Benjamin Kosnik  <bkoz@redhat.com>

	* libstdc++-v3: New directory.

From-SVN: r33317
2000-04-21 20:33:34 +00:00

86 lines
2.2 KiB
C++

// -*- C++ -*- C math library.
// Copyright (C) 1997, 1998, 1999, 2000 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
// Code for signatures not found in the C library
//
#include <bits/std_cmath.h>
namespace std {
namespace {
template <typename T>
inline T pow_helper(T x, unsigned int y)
{
T z = y&1? x : 1;
while(y >>= 1)
{
x *= x;
if(y & 1) z *= x;
}
return z;
}
}
float
pow(float x, int y)
{
if(y < 0)
return 1.0f/pow_helper(x, -y);
else
return pow_helper(x, y);
}
double
pow(double x, int y)
{
if(y < 0)
return 1.0/pow_helper(x, -y);
else
return pow_helper(x, y);
}
long double
pow(long double x, int y)
{
if(y < 0)
return 1.0l/pow_helper(x, -y);
else
return pow_helper(x, y);
}
} // std