95 lines
2.5 KiB
C
95 lines
2.5 KiB
C
|
/* _LDnorm function -- IEEE 754 version */
|
||
|
|
#include "xmath.h"
|
||
|
|
_STD_BEGIN
|
||
|
|
|
||
|
|
#if _DLONG == 0
|
||
|
|
/* not needed -- 64-bit */
|
||
|
|
|
||
|
|
#elif _DLONG == 1
|
||
|
|
_CRTIMP2 short __cdecl _LDnorm(unsigned short *ps)
|
||
|
|
{ /* normalize long double fraction -- 80-bit */
|
||
|
|
short xchar;
|
||
|
|
unsigned short sign = ps[_L0];
|
||
|
|
|
||
|
|
xchar = 0;
|
||
|
|
for (ps[_L0] = 0; ps[_L0] == 0 && ps[_L1] < 0x100;
|
||
|
|
xchar -= 16)
|
||
|
|
{ /* shift left by 16 */
|
||
|
|
ps[_L0] = ps[_L1];
|
||
|
|
ps[_L1] = ps[_L2], ps[_L2] = ps[_L3];
|
||
|
|
ps[_L3] = ps[_L4], ps[_L4] = 0;
|
||
|
|
}
|
||
|
|
if (ps[_L0] == 0)
|
||
|
|
for (; ps[_L1] < (1U << _LOFF); --xchar)
|
||
|
|
{ /* shift left by 1 */
|
||
|
|
ps[_L1] = ps[_L1] << 1 | ps[_L2] >> 15;
|
||
|
|
ps[_L2] = ps[_L2] << 1 | ps[_L3] >> 15;
|
||
|
|
ps[_L3] = ps[_L3] << 1 | ps[_L4] >> 15;
|
||
|
|
ps[_L4] <<= 1;
|
||
|
|
}
|
||
|
|
for (; ps[_L0] != 0; ++xchar)
|
||
|
|
{ /* shift right by 1 */
|
||
|
|
ps[_L4] = ps[_L4] >> 1 | ps[_L3] << 15;
|
||
|
|
ps[_L3] = ps[_L3] >> 1 | ps[_L2] << 15;
|
||
|
|
ps[_L2] = ps[_L2] >> 1 | ps[_L1] << 15;
|
||
|
|
ps[_L1] = ps[_L1] >> 1 | ps[_L0] << 15;
|
||
|
|
ps[_L0] >>= 1;
|
||
|
|
}
|
||
|
|
ps[_L0] = sign;
|
||
|
|
return (xchar);
|
||
|
|
}
|
||
|
|
|
||
|
|
#else /* 1 < _DLONG */
|
||
|
|
_CRTIMP2 short __cdecl _LDnorm(unsigned short *ps)
|
||
|
|
{ /* normalize long double fraction -- 128-bit SPARC */
|
||
|
|
short xchar;
|
||
|
|
unsigned short sign = ps[_L0];
|
||
|
|
|
||
|
|
xchar = 1;
|
||
|
|
if (ps[_L1] != 0 || ps[_L2] != 0 || ps[_L3] != 0
|
||
|
|
|| ps[_L4] != 0 || ps[_L5] != 0 || ps[_L6] != 0
|
||
|
|
|| ps[_L7] != 0)
|
||
|
|
{ /* nonzero, scale */
|
||
|
|
for (ps[_L0] = 0; ps[_L0] == 0 && ps[_L1] < 0x100;
|
||
|
|
xchar -= 16)
|
||
|
|
{ /* shift left by 16 */
|
||
|
|
ps[_L0] = ps[_L1];
|
||
|
|
ps[_L1] = ps[_L2], ps[_L2] = ps[_L3];
|
||
|
|
ps[_L3] = ps[_L4], ps[_L4] = ps[_L5];
|
||
|
|
ps[_L5] = ps[_L6], ps[_L6] = ps[_L7];
|
||
|
|
ps[_L7] = 0;
|
||
|
|
}
|
||
|
|
for (; ps[_L0] == 0; --xchar)
|
||
|
|
{ /* shift left by 1 */
|
||
|
|
ps[_L0] = ps[_L0] << 1 | ps[_L1] >> 15;
|
||
|
|
ps[_L1] = ps[_L1] << 1 | ps[_L2] >> 15;
|
||
|
|
ps[_L2] = ps[_L2] << 1 | ps[_L3] >> 15;
|
||
|
|
ps[_L3] = ps[_L3] << 1 | ps[_L4] >> 15;
|
||
|
|
ps[_L4] = ps[_L4] << 1 | ps[_L5] >> 15;
|
||
|
|
ps[_L5] = ps[_L5] << 1 | ps[_L6] >> 15;
|
||
|
|
ps[_L6] = ps[_L6] << 1 | ps[_L7] >> 15;
|
||
|
|
ps[_L7] <<= 1;
|
||
|
|
}
|
||
|
|
for (; 1 < ps[_L0]; ++xchar)
|
||
|
|
{ /* shift right by 1 */
|
||
|
|
ps[_L7] = ps[_L7] >> 1 | ps[_L6] << 15;
|
||
|
|
ps[_L6] = ps[_L6] >> 1 | ps[_L5] << 15;
|
||
|
|
ps[_L5] = ps[_L5] >> 1 | ps[_L4] << 15;
|
||
|
|
ps[_L4] = ps[_L4] >> 1 | ps[_L3] << 15;
|
||
|
|
ps[_L3] = ps[_L3] >> 1 | ps[_L2] << 15;
|
||
|
|
ps[_L2] = ps[_L2] >> 1 | ps[_L1] << 15;
|
||
|
|
ps[_L1] = ps[_L1] >> 1 | ps[_L0] << 15;
|
||
|
|
ps[_L0] >>= 1;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
ps[_L0] = sign;
|
||
|
|
return (xchar);
|
||
|
|
}
|
||
|
|
#endif
|
||
|
|
_STD_END
|
||
|
|
|
||
|
|
/*
|
||
|
|
* Copyright (c) 1992-2001 by P.J. Plauger. ALL RIGHTS RESERVED.
|
||
|
|
* Consult your license regarding permissions and restrictions.
|
||
|
|
V3.10:0009 */
|