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 pointers;

struct S
{
    long l;
}

void main()
{
    int j = 42;
    int* p = &j;

    auto t = *p;
    *p ^= t;

    *p = ~t;

    S s;
    S* sp = &s;
    *sp = s;
    s = *sp;
}