Logical Instructions; Eor - Xerox 550 Reference Manual

Condition code settings:
2 3 4 Result of Comparison
- 0 0 Contents of R equal to effective word.
o
Contents of R less than effective word.
o
Contents of R greater than effective word.
o
0
- Contents of Ru 1 equa
I
to effecti ve word.
o
- Contents of Ru 1 less than effective word.
o
- Contents of Ru1 greater than effective word.
elM
COMPARE WITH LIMITS IN MEMORY
(Doubleword index alignment)
COMPARE WITH LIMITS IN MEMORY simultaneously com-
pares the contents of register R with the 32 high-order bits
of the effective doubleword and with the 32 low-order bits
of the effective doubleword, with all three words treated
as 32-bit signed quantities, and sets the condition code
according to the results of the comparisons.
Affected: CC
(R) : ED
O
_
31
; (R) : ED
32
-63
Condition code settings:
2 3 4 Result of Comparison
- 0 0
Contents of R equal to most signifi cant word,
(R)
=
ED
O
_
31
'
- 0
Contents of R
less
than most significant word,
(R)
<
ED
O
_
31
'
o
Contents of R greater than most significant
word, (R)
>
ED
O
_
31
'
o
0
- Contents of R equal to
least
significant word,
(R)
=
ED
32
_
63
.
o
o
- Contents of R
less
than
least
significant word,
(R)
<
ED
32
_
63
.
- Contents of R greater than
least
significant
word, (R)
>
ED
32
_
63
.
LOGICAL INSTRUCTIONS
All logical operations are performed bit by corresponding
bit between two operands; one operand is in register Rand
68 Log i co
I
Instru ct i ons
the other operand is the effective word. The result of the
logical
operation is loaded into register R.
OR
OR WORD
(Word index alignment)
o
1 2
OR WORD
logically
ORs the effective word into register
R.
If corresponding bits of register R and the effective word
are both
0,
a
0
remains in register
R;
otherwise, a 1 is
placed in the corresponding bit position of register R. The
effective word is not affected.
Affected: (R), CC3, CC4
(R) u EW - R, where
0
u
0
=
0, 0
u 1
=
1, 1 u
0
=
1,
1
u
1
=
1
Condition code settings:
2 3 4 Result in R
- 0 0
Zero.
- - 0 Bit 0 of register R is a
1.
o
Bit
0
of register R is a
0
and bit positions 1-31
of register R contain at least one 1.
EOR
EXCLUSIVE OR WORD
(Word index alignment)
EXCLUSIVE OR WORD
logically
exclusive ORs the effec-
tive word into register R.
If
corresponding bits of regis-
ter R and the effective word are different! a 1 is placed in
the corresponding bit position of register R; if the contents
of the corresponding bit positions are alike, a
0
is placed
in the corresponding bit position of register R. The effec-
tive word is not affected.
Affected: (R), CC3, CC4
(R)
(Q)
EW--R
Condition code settings:
2 3 4 Resu
It
in R
o
0 Zero.
- 0 Bit 0 of register R is a
1.
OBit 0 of register R is a 0 and bit positions 1-31
of register R contain at least one 1.