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/* Public domain. */
typedef int DItype __attribute__ ((mode (DI)));
typedef unsigned int UDItype __attribute__ ((mode (DI)));
typedef unsigned int USItype __attribute__ ((mode (SI)));
typedef float SFtype __attribute__ ((mode (SF)));
typedef float DFtype __attribute__ ((mode (DF)));
SFtype __floatundisf (UDItype);
SFtype
__floatundisf (UDItype u)
{
/* Protect against double-rounding error.
Represent any low-order bits, that might be truncated by a bit that
won't be lost. The bit can go in anywhere below the rounding position
of SFTYPE. A fixed mask and bit position handles all usual
configurations. */
if (53 < (sizeof (DItype) * 8)
&& 53 > ((sizeof (DItype) * 8) - 53 + 24))
{
if (u >= ((UDItype) 1 << 53))
{
if ((UDItype) u & (((UDItype) 1 << (sizeof (DItype) * 8 - 53)) - 1))
{
u &= ~ (((UDItype) 1 << (sizeof (DItype) * 8 - 53)) - 1);
u |= (UDItype) 1 << (sizeof (DItype) * 8 - 53);
}
}
}
/* Do the calculation in a wider type so that we don't lose any of
the precision of the high word while multiplying it. */
DFtype f = (USItype) (u >> (sizeof (USItype) * 8));
f *= 0x1p32f;
f += (USItype) u;
return (SFtype) f;
}
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