Testing EQV (equivalence) operator:
-1 EQV -1 = -1  (expected: -1)
-1 EQV 0 =  0  (expected: 0)
0 EQV -1 =  0  (expected: 0)
0 EQV 0 = -1  (expected: -1)

Testing IMP (implication) operator:
-1 IMP -1 = -1  (expected: -1)
-1 IMP 0 =  0  (expected: 0)
0 IMP -1 = -1  (expected: -1)
0 IMP 0 = -1  (expected: -1)

Bitwise tests:
5 EQV 3 = -7  (5=101b, 3=011b)
5 IMP 3 = -5  (5=101b, 3=011b)
15 EQV 7 = -9  (15=1111b, 7=0111b)
15 IMP 7 = -9  (15=1111b, 7=0111b)
