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 alignment;

align(1) struct S
{
    ubyte b;
    int i;
    ubyte[2] b2;
    long l;
    real r;
}

void main()
{
    byte b;
    short s;
    int i;
    long l;
    float f;
    double d;
    real r;
}