blob: fde1d00aaa903ad4cfaf614a1a2e8e975f7e8517 [file] [log] [blame]
/* Checksum some values used in TCP/UDP headers.
* The gain by doing this in asm is that C will not generate carry-additions
* for the 32-bit components of the checksum, so otherwise we would have had
* to split all of those into 16-bit components, then add.
extern inline unsigned int
csum_tcpudp_nofold(unsigned long saddr, unsigned long daddr, unsigned short len,
unsigned short proto, unsigned int sum)
int res;
__asm__ ("add.d %2, %0\n\t"
"add.d %3, %0\n\t"
"add.d %4, %0\n\t"
"addq 0, %0\n"
: "=r" (res)
: "0" (sum), "r" (daddr), "r" (saddr), "r" ((ntohs(len) << 16) + (proto << 8)));
return res;