2  * Compute 16-bit sum in ones' complement arithmetic (with end-around carry).
3  * This sum is often used as a simple checksum in networking.
16     uint32_t sum = 0;  in slurp_head32()  local
24 	sum = load32(ptr32) & mask;  in slurp_head32()
28     return sum;  in slurp_head32()
36     uint64_t sum = 0;  in __chksum()  local
42 	sum = slurp_head32(&ptr, &nbytes);  in __chksum()
46     /* Sum all 16-byte chunks */  in __chksum()
54 	sum += h0 + h1 + h2 + h3;  in __chksum()
63 	sum += load32(cptr);  in __chksum()
71 	sum += load16(cptr);  in __chksum()
77 	sum += *(uint8_t *)cptr;  in __chksum()
80     return fold_and_swap(sum, swap);  in __chksum()