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#include "f2c.h"
#ifdef __cplusplus
extern "C" {
#endif
#ifndef LONGBITS
#define LONGBITS 32
#endif
integer
#ifdef KR_headers
lbit_bits(a, b, len) integer a, b, len;
#else
lbit_bits(integer a, integer b, integer len)
#endif
{
/* Assume 2's complement arithmetic */
unsigned long x, y;
x = (unsigned long) a;
y = (unsigned long)-1L;
x >>= b;
y <<= len;
return (integer)(x & ~y);
}
integer
#ifdef KR_headers
lbit_cshift(a, b, len) integer a, b, len;
#else
lbit_cshift(integer a, integer b, integer len)
#endif
{
unsigned long x, y, z;
x = (unsigned long)a;
if (len <= 0) {
if (len == 0)
return 0;
goto full_len;
}
if (len >= LONGBITS) {
full_len:
if (b >= 0) {
b %= LONGBITS;
return (integer)(x << b | x >> LONGBITS -b );
}
b = -b;
b %= LONGBITS;
return (integer)(x << LONGBITS - b | x >> b);
}
y = z = (unsigned long)-1;
y <<= len;
z &= ~y;
y &= x;
x &= z;
if (b >= 0) {
b %= len;
return (integer)(y | z & (x << b | x >> len - b));
}
b = -b;
b %= len;
return (integer)(y | z & (x >> b | x << len - b));
}
#ifdef __cplusplus
}
#endif
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