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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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