/* Copyright (C) 1998, 1999, 2000  Free Software Foundation

   This file is part of libgcj.

This software is copyrighted work licensed under the terms of the
Libgcj License.  Please consult the file "LIBGCJ_LICENSE" for
details.  */
 
/**
 * @author Andrew Haley <aph@cygnus.com>
 * @date Tue Sep 22 1998 */
/* Written using "Java Class Libraries", 2nd edition, ISBN 0-201-31002-3
 * "The Java Language Specification", ISBN 0-201-63451-1
 * plus online API docs for JDK 1.2 beta from http://www.javasoft.com.
 * Status:  Believed complete and correct.
 */
 
#include <config.h>

#include <java/lang/String.h>
#include <java/lang/Float.h>
#include <java/lang/Double.h>
#include <java/lang/Integer.h>
#include <java/lang/Long.h>
#include <java/lang/Math.h>
#include <gcj/array.h>

#include "fdlibm.h"

extern "C" float fabsf (float);

jdouble java::lang::Math::cos(jdouble x)
{
  return (jdouble)::cos((double)x);
}  

jdouble java::lang::Math::sin(jdouble x)
{
  return (jdouble)::sin((double)x);
}  

jdouble java::lang::Math::tan(jdouble x)
{
  return (jdouble)::tan((double)x);
}  

jdouble java::lang::Math::asin(jdouble x)
{
  return (jdouble)::asin((double)x);
}  

jdouble java::lang::Math::acos(jdouble x)
{
  return (jdouble)::acos((double)x);
}  

jdouble java::lang::Math::atan(jdouble x)
{
  return (jdouble)::atan((double)x);
}  

jdouble java::lang::Math::atan2(jdouble y, jdouble x)
{
  return (jdouble)::atan2((double)y, (double)x);
}  

jdouble java::lang::Math::log(jdouble x)
{
  return (jdouble)::log((double)x);
}  

jdouble java::lang::Math::exp(jdouble x)
{
  return (jdouble)::exp((double)x);
}  

jdouble java::lang::Math::sqrt(jdouble x)
{
  return (jdouble)::sqrt((double)x);
}  

jdouble java::lang::Math::pow(jdouble y, jdouble x)
{
  return (jdouble)::pow((double)y, (double)x);
}  

jdouble java::lang::Math::IEEEremainder(jdouble y, jdouble x)
{
  return (jdouble)::__ieee754_remainder((double)y, (double)x);
}  

jdouble java::lang::Math::abs(jdouble x)
{
  return (jdouble)::fabs((double)x);
}  

jfloat java::lang::Math::abs(jfloat x)
{
  return (jfloat)::fabsf((float)x);
}  

jdouble java::lang::Math::rint(jdouble x)
{
  return (jdouble)::rint((double)x);
}  

jint java::lang::Math::round(jfloat x)
{
  if (x != x)
    return 0;
  if (x <= (jfloat)java::lang::Integer::MIN_VALUE)
    return java::lang::Integer::MIN_VALUE;
  if (x >= (jfloat)java::lang::Integer::MAX_VALUE)
    return java::lang::Integer::MAX_VALUE;

  return (jint)::rintf((float)x);
}  

jlong java::lang::Math::round(jdouble x)
{
  if (x != x)
    return 0;
  if (x <= (jdouble)java::lang::Long::MIN_VALUE)
    return java::lang::Long::MIN_VALUE;
  if (x >= (jdouble)java::lang::Long::MAX_VALUE)
    return java::lang::Long::MAX_VALUE;

  return (jlong)::rint((double)x);
}  

jdouble java::lang::Math::floor(jdouble x)
{
  return (jdouble)::floor((double)x);
}  

jdouble java::lang::Math::ceil(jdouble x)
{
  return (jdouble)::ceil((double)x);
}  

static inline int
floatToIntBits (jfloat value)
{
  union {
    jint l;
    jfloat d;
  } u;
  u.d = value;
  return u.l;
}

static inline bool
isNaN (jint bits)
{
  jint e = bits & 0x7f800000;
  jint f = bits & 0x007fffff;

  return e == 0x7f800000 && f != 0;
}

jfloat
java::lang::Math::min(jfloat a, jfloat b)
{
  jint abits = floatToIntBits (a);
  jint bbits = floatToIntBits (b);
  
  if (isNaN (abits) || isNaN (bbits))
    return java::lang::Float::NaN;
  
  if (abits >= 0) // a is +ve
    return bbits < 0 ? b  // a is +ve, b is -ve.
      // a and b are both +ve, so compare magnitudes: the number with
      // the smallest magnitude is the smallest
      : (abits < bbits ? a : b);
  else // a is -ve
    return bbits >= 0 ? a  // a is -ve, b is +ve.
      // a and b are both -ve, so compare magnitudes: the number with
      // the biggest magnitude is the smallest
      : (abits > bbits ? a : b);
}

jfloat 
java::lang::Math::max(jfloat a, jfloat b)
{
  jint abits = floatToIntBits (a);
  jint bbits = floatToIntBits (b);
  
  if (isNaN (abits) || isNaN (bbits))
    return java::lang::Float::NaN;
  
  if (abits >= 0) // a is +ve
    return bbits < 0 ? a  // a is +ve, b is -ve.
      // a and b are both +ve, so compare magnitudes: the number with
      // the smallest magnitude is the smallest
      : (abits > bbits ? a : b);
  else // a is -ve
    return bbits >= 0 ? b  // a is -ve, b is +ve.
      // a and b are both -ve, so compare magnitudes: the number with
      // the biggest magnitude is the smallest
      : (abits < bbits ? a : b);
}

static inline jlong
doubleToLongBits (jdouble value)
{
  union {
    jlong l;
    jdouble d;
  } u;
  u.d = value;
  return u.l;
}

static inline bool 
isNaN (jlong bits)
{
  jlong e = bits & 0x7ff0000000000000LL;
  jlong f = bits & 0x000fffffffffffffLL;
  
  return e == 0x7ff0000000000000LL && f != 0LL;
}


jdouble
java::lang::Math::min(jdouble a, jdouble b)
{
  jlong abits = doubleToLongBits (a);
  jlong bbits = doubleToLongBits (b);
  
  if (isNaN (abits) || isNaN (bbits))
    return java::lang::Double::NaN;

  if (abits >= 0LL) // a is +ve
    return bbits < 0LL ? b  // a is +ve, b is -ve.
      // a and b are both +ve, so compare magnitudes: the number with
      // the smallest magnitude is the smallest
      : (abits < bbits ? a : b);
  else // a is -ve
    return bbits >= 0LL ? a  // a is -ve, b is +ve.
      // a and b are both -ve, so compare magnitudes: the number with
      // the biggest magnitude is the smallest
      : (abits > bbits ? a : b);
}

jdouble
java::lang::Math::max(jdouble a, jdouble b)
{
  jlong abits = doubleToLongBits (a);
  jlong bbits = doubleToLongBits (b);
  
  if (isNaN (abits) || isNaN (bbits))
    return java::lang::Double::NaN;

  if (abits >= 0LL) // a is +ve
    return bbits < 0LL ? a  // a is +ve, b is -ve.
      // a and b are both +ve, so compare magnitudes: the number with
      // the smallest magnitude is the smallest
      : (abits > bbits ? a : b);
  else // a is -ve
    return bbits >= 0LL ? b  // a is -ve, b is +ve.
      // a and b are both -ve, so compare magnitudes: the number with
      // the biggest magnitude is the smallest
      : (abits < bbits ? a : b);
}