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word locations, and register doublewords in memory double-
word locations.
Store instructions do not affect the contents
of the general register specified by the R field of the instruc-
tion, unless the same register is also specified by the effec-
tive virtual address of the instruction.
II
LOAD IMMEDIATE
(Immediate operand)
o
1
LOAD IMMEDIATE extends the sign of the value field (bit
position 12 of the instruction ward) 12 bit positions to the
left and then loods the 32-bit result into register R.
Affected: (R), CC3, CC4
(I)12-31SE
-
R
Conditi on code setti ngs:
2
3
4
Result in R
0
0
zero
0
1
negative
0
positive
If
LI is indirectly addressed, it is treated as a nonexistent
instruction, in .which case the computer unconditionally
aborts execution of the instruction (at the time of opera-
tion code decoding) and traps to location
X '
40' with the
contents of register R and the condition code unchanged.
LB
LOAD BYTE
(Byte index alignment)
LOAD BYTE loads the effective byte into bit positions 24-31
of register R and clears bit positions 0-23 of the reg ister to
allOls.
Affected: (R), CC3, CC4
EB -
R 24 - 31 ; 0 -
R O - 23
Condition code settings:
2
LH
3
o
1
4
o
o
Result in R
zero
nonzero
LOAD HALFWORD
(Halfword index alignment)
LOAD HALFWOR D extends the sign of the effective half-
word 16 bit positions to the left and then loads the 32-bit
result into register R.
Affected: (R),CC3,CC4
EHSE
R
Load/Store Instructions
Condition code settings:
2
3
4
Result in R
0
0
zero
0
1
negative
1
0
positive
.LW
LOAD WORD
(Word index al ignment)
LOAD WORD loads the effective word into register R.
Affected: (R),CC3,CC4
EW -
R
Condition code settings:
2
3
4
Result in R
o
0
zero
o
1
negative
1
0
positive
.LD
LOAD DOUBLEWORD
(Doubleword index alignment)
LOAD DOUBLEWORD loads the 32 low-order bits of the ef-
fective doubleword into register Ru 1 and then loads the 32
high-order bits of the effective douhleword into register R.
If R is an odd value, the result in register R is the 32 high-
order bits of the effective doubleword. The condition code
settings are based on the effective doubleword, rather than
the
final result in register R (see Example 3, below).
Affected: (R),(Ru 1 ),CC3,CC4
ED
32
-
63
-
Rul; ED
O
_
31
-
R
Condition code settings:
2
3
4
Effective doubleword
o
0
o
1
1
0
zero
negative
positive
Example 1, even R field value:
ED
(R)
(Ru 1)
CC
Before execution
After execution
X
1
0123456789ABCDEF ' X ' 0123456789ABCDEF
I
xxxxxxxx
X
1
01234567
1
xxxxxxxx
X '
89ABCDEF '
xxx x
xx 10
Example 2, odd R field value:
ED
(R)
CC
X ' 0123456789ABCDEF'
X '
0123456789ABCDEF'
xxxxxxxx
X '
01234567
1
xxxx
Page 32
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