63 lines
999 B
C
63 lines
999 B
C
#include "f2c.h"
|
|
|
|
#ifndef LONGBITS
|
|
#define LONGBITS 32
|
|
#endif
|
|
|
|
#ifndef LONG8BITS
|
|
#define LONG8BITS (2*LONGBITS)
|
|
#endif
|
|
|
|
integer
|
|
qbit_bits (longint a, integer b, integer len)
|
|
{
|
|
/* Assume 2's complement arithmetic */
|
|
|
|
ulongint x, y;
|
|
|
|
x = (ulongint) a;
|
|
y = (ulongint) - 1L;
|
|
x >>= b;
|
|
y <<= len;
|
|
return (longint) (x & y);
|
|
}
|
|
|
|
longint
|
|
qbit_cshift (longint a, integer b, integer len)
|
|
{
|
|
ulongint x, y, z;
|
|
|
|
x = (ulongint) a;
|
|
if (len <= 0)
|
|
{
|
|
if (len == 0)
|
|
return 0;
|
|
goto full_len;
|
|
}
|
|
if (len >= LONG8BITS)
|
|
{
|
|
full_len:
|
|
if (b >= 0)
|
|
{
|
|
b %= LONG8BITS;
|
|
return (longint) (x << b | x >> LONG8BITS - b);
|
|
}
|
|
b = -b;
|
|
b %= LONG8BITS;
|
|
return (longint) (x << LONG8BITS - b | x >> b);
|
|
}
|
|
y = z = (unsigned long) -1;
|
|
y <<= len;
|
|
z &= ~y;
|
|
y &= x;
|
|
x &= z;
|
|
if (b >= 0)
|
|
{
|
|
b %= len;
|
|
return (longint) (y | z & (x << b | x >> len - b));
|
|
}
|
|
b = -b;
|
|
b %= len;
|
|
return (longint) (y | z & (x >> b | x << len - b));
|
|
}
|