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#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))));
}
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