#include "io.h" int main(void) { long long rt, rs; long long res; rt = 0x1234567887654321; rs = 0xabcd1234abcd8765; res = 0x1234567887654321; __asm ("prependw %0, %1, 0x0\n\t" : "=r"(rt) : "r"(rs) ); if (rt != res) { printf("prependw error\n"); return -1; } rt = 0x1234567887654321; rs = 0xabcd1234abcd8765; res = 0x5123456788765432; __asm ("prependw %0, %1, 0x4\n\t" : "=r"(rt) : "r"(rs) ); if (rt != res) { printf("prependw error\n"); return -1; } return 0; }