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 mini.foreach6;

struct S
{
    long l;
    float f;
}

void main()
{
    S[4] arr = void;
    foreach(i,v;arr) {
        v = S(i, i*2.5);
    }
}