Fix some unittests for 64-bit asm. They were operating on int variables as if they were longs. This was causing asm1_1 to fail when compiled with -O3 because it was overwriting the spilled value of callee-saved register %rbx, which the runtime was using as a pointer value at the time.

module bug62;
extern(C) int printf(char*, ...);

void main()
{
    int[] arr = [1,2,5,7,9];
    int i = 0;
    foreach(v; arr) {
        i += v;
    }
    printf("sum = %d\n", i);
    assert(i == 24);
}