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treated as positive integer magnitudes) and sets the condi-
tion code according to the results of the comparison.
Affected:
CC2, CC3, CC4
(R)24-31 : EB
Condition code settings:
CH
2
3
4
Result of Comparison
o
o
o
o
1
o
equal
register byte less than effective byte
register byte greater than effective byte
no l-bits compare, (R)24-31
n
EB
=
0
one or more l-bits compare,
(R)24-31
n
EB
-I
0
COMPARE HALFWORD
(Halfword index alignment)
COMPARE HALFWORD extends the sign of the effective hal f-
word 16 bit positions to the
I
eft, then compares the resultant
32-bit word with the contents of register R (with both words
treated as signed, fixed-poin
l
quantities) and sets the condi-
tion code according to the results of the comparison.
Affected:
CC2, CC3, CC4
(R) : EHSE
Condition code settings:
2
3
4
Result of Comparison
o
o
0
equal
o
register word less than effective half-
word wi th si gn extended
o
register word greater than effective
halfword with sign extended
no 1-b its compare, (R) n EH SE
=
0
one or more 1-bits compare,
(R)
n
EHSEfO
CW
COMPARE WORD
(Word index alignment)
COMPARE WORD compares the contents of register R with
the effective word, with both words treated as signed fixed-
poi nt quantities, and sets the condition code according to
the results of the comparison.
Affected: CC2, CC3, CC4
(R) :
EW
Condition code setti ngs:
2
3
4
Result of Comparison
- - - - - -
o
0
equal
o
register word less than effective word
CD
2
3
4
Result of Comparison
o
reg i ster word greater than effect i ve word
o
no 1-bits compare, (R) n EW
=
0
1
one or more l-bits compare,
(R)
n
EVv
fa
COMPARE DOUBLEWORD
(Doubleword index alignment)
COMPARE DOUBLEVvORD compares the effective double-
word with the contents of registers Rand Ru
1
(with both
doublewords treated as signed, fixed-point quantities) and
sets the condition code accordi ng to the resul ts of the com-
parison. If the R field of CD is an odd value, CD forms a
64-bit register operand (by duplicating the contents of reg-
ister R for both the 32 high-order bits and the 32 low-order
bits) and compares the effective doubl eword with the 64-bi t
register operand.
The condition code settings are based on
the 64-bit comparison.
Affected: CC3, CC4
(R, Ru 1) : ED
Condition code settings:
2
cs
3
4
Result of Comparison
0
0
equal
{)
register doubleword less than effective
doubleword
0
register dou91eword greater than effective
doubleword
COMPARE SELECTIVE
(Word index alignment)
COMPARE SELECTIVE compares the contents of register R
with the effective word in only those bit positions selected by
a 1 in corresponding bit positions of register Ru 1 (mask). The
contentsof register R and the effective word are ignored in
those bit positions designated by a
0
in corresponding bit
positions of register Ru 1. The selected contents of register R
and the effective word are treated as positive integer mag-
nitudes, and the condition code is set according to the re-
sult of the comparison.
If the R field of CS is an odd value,
CS compares the contents of register R wi th the logical prod-
uct (AND) of the effective word and the contents of regi ster R.
Affected: CC3,CC4
If R is even: (R) n(Ru
1) : EW n(Ru 1)
If R is odd: (R) : EW n(R)
Condition code settings:
2
3
4
o
0
o
1
1
0
Results of Comparison under Mask in Rul
equal
register word less than effective word
register word greater than effective word
(if R is even)
Comparison Instructions
45
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