And/Or/Xor

Affected Flags
C	V	N	Z
		X	X

and : Register2 = Register2 & Register1
or : Register2 = Register2 | Register1
xor : Register2 = Register2 ^ Register1

These tree instructions perform bitwise boolean and, or and xor operations. The following thruth tables show you the behavior of these functions.

And
	0	1
0	0	0
1	0	1

Or
	0	1
0	0	1
1	1	1

Xor
	0	1
0	0	1
1	1	0

Forms and variants

rx = source register
ry = destination register

Form	Effect
and.b ry,rx	rx <- rx and ry
and.w ry,rx
and.l ry,rx
or.b ry,rx	rx <- rx or ry
or.w ry,rx
or.l ry,rx
xor.b ry,rx	rx <- rx xor ry
xor.w ry,rx
xor.l ry,rx

Instruction encoding

S = Source register number
D = Destination register number

Instruction	Op Code	Cycles	Encoding
and.b ry,rx	10	6	00010000 SSSSDDDD
and.w ry,rx	50	6	01010000 SSSSDDDD
and.l ry,rx	90	6	10010000 SSSSDDDD
or.b ry,rx	11	6	00010001 SSSSDDDD
or.w ry,rx	51	6	01010001 SSSSDDDD
or.l ry,rx	91	6	10010001 SSSSDDDD
xor.b ry,rx	12	6	00010010 SSSSDDDD
xor.w ry,rx	52	6	01010010 SSSSDDDD
xor.l ry,rx	92	6	10010010 SSSSDDDD

Code Examples

Note: This example is for understanding and can be optimized.

// Example : Simple (naive) Checksum of a c-style text string

; r0 = pointer to string (in)
; r0 = result (out)

checksum: pushregs r1-r2
          movex.b #0,r1
loop:     move.b(r0),r2
          beq out
          inc #1,r0
          add.b  r2,r1
          bra loop
out:      move.b r1,r0
          popregs r1-r2
          rts

And/Or/Xor

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