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#include "f2c.h"
#ifndef LONGBITS
#define LONGBITS 32
#endif
#ifndef LONG8BITS
#define LONG8BITS (2*LONGBITS)
#endif
integer
#ifdef KR_headers
qbit_bits(a, b, len) longint a; integer b, len;
#else
qbit_bits(longint a, integer b, integer len)
#endif
{
/* Assume 2's complement arithmetic */
ulongint x, y;
x = (ulongint) a;
y = (ulongint)-1L;
x >>= b;
y <<= len;
return (longint)(x & y);
}
longint
#ifdef KR_headers
qbit_cshift(a, b, len) longint a; integer b, len;
#else
qbit_cshift(longint a, integer b, integer len)
#endif
{
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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