#ifndef INT_TO_FLOAT_H
#define INT_TO_FLOAT_H

/* Taken from here: */
/* https://android.googlesource.com/toolchain/gcc/+/master/gcc-4.9/libgcc/config/m68k/fpgnulib.c */

/* the following deal with IEEE single-precision numbers */
#define EXCESS		126L
#define SIGNBIT		0x80000000L
#define HIDDEN		(1L << 23L)
#define SIGN(fp)	((fp) & SIGNBIT)
#define EXP(fp)		(((fp) >> 23L) & 0xFF)
#define MANT(fp)	(((fp) & 0x7FFFFFL) | HIDDEN)
#define PACK(s,e,m)	((s) | ((e) << 23L) | (m))
/* the following deal with IEEE double-precision numbers */
#define EXCESSD		1022L
#define HIDDEND		(1L << 20L)
#define EXPDBITS	11
#define EXPDMASK	0x7FFL
#define EXPD(fp)	(((fp.l.upper) >> 20L) & 0x7FFL)
#define SIGND(fp)	((fp.l.upper) & SIGNBIT)
#define MANTD(fp)	(((((fp.l.upper) & 0xFFFFF) | HIDDEND) << 10) | \
				(fp.l.lower >> 22))
#define MANTDMASK	0xFFFFFL /* mask of upper part */

union double_long 
{
  double d;
  struct {
      long upper;
      unsigned long lower;
    } l;
};

/* convert unsigned int to double */
double
__floatunsidf (unsigned long a1)
{
  long exp = 32 + EXCESSD;
  union double_long dl;
  if (!a1)
    {
      dl.l.upper = dl.l.lower = 0;
      return dl.d;
    }
  while (a1 < 0x2000000L)
    {
      a1 <<= 4;
      exp -= 4;
    }
  while (a1 < 0x80000000L)
    {
      a1 <<= 1;
      exp--;
    }
  /* pack up and go home */
  dl.l.upper = exp << 20L;
  dl.l.upper |= (a1 >> 11L) & ~HIDDEND;
  dl.l.lower = a1 << 21L;
  return dl.d;
}
/* convert int to double */
double
__floatsidf (long a1)
{
  long sign = 0, exp = 31 + EXCESSD;
  union double_long dl;
  if (!a1)
    {
      dl.l.upper = dl.l.lower = 0;
      return dl.d;
    }
  if (a1 < 0)
    {
      sign = SIGNBIT;
      a1 = (long)-(unsigned long)a1;
      if (a1 < 0)
	{
	  dl.l.upper = SIGNBIT | ((32 + EXCESSD) << 20L);
	  dl.l.lower = 0;
	  return dl.d;
        }
    }
  while (a1 < 0x1000000L)
    {
      a1 <<= 4;
      exp -= 4;
    }
  while (a1 < 0x40000000L)
    {
      a1 <<= 1;
      exp--;
    }
  /* pack up and go home */
  dl.l.upper = sign;
  dl.l.upper |= exp << 20L;
  dl.l.upper |= (a1 >> 10L) & ~HIDDEND;
  dl.l.lower = a1 << 22L;
  return dl.d;
}

/* convert unsigned int to float */
float
__floatunsisf (unsigned long l)
{
  double foo = __floatunsidf (l);
  return foo;
}

/* convert int to float */
float
__floatsisf (long l)
{
  double foo = __floatsidf (l);
  return foo;
}

#endif /* INT_TO_FLOAT_H */