Xerox 560 Reference Manual page 58

LCW
LOAD COMPLEMENT WORD
0/Vord index alignment)
LOAD COMPLEMENT WORD loads the 32-bit two's com-
plement of the effective word into register R. Fixed-point
overflow occurs if the effective word is -2 31 (X'80000000')
in which case the result in register R is -2 31 and CC2 is set
to 1; otherwise, CC2 is reset to
O.
Affected: (R),CC2,CC3,CC4 Trap: Fixed-pointoverflow.
-EW-R
Condition code settings:
2 3
4
Result in R
- 0 0 0 Zero
- 0 Negative
- 0 0 Positive
- 0 No fixed-point overflow
o
Fixed-point overflow
If CC2 is set to 1 and the fixed-point arithmetic trap mask
(AM) is a 1, the BP traps to location X'43' after execution
of LOAD COMPLEMENT WORD; otherwise, the BP ex-
ecutes the next instruction in sequence.
LAW
LOAD ABSOLUTE WORD
0/Vord index alignment)
If the effective word is positive, LOAD ABSOLUTE WORD
!oads the effective v.'ord into regi$ter R. If the effective
word is negative, LAW loads the 32-bit two's complement
of the effective word into register R. Fixed-point overflow
occurs if the effective word is
-~
1 (X'80000000'), in
which case the result in register R is _2 31 , and CC2 is set
to
1;
otherwise, CC2 is reset to
O.
Affected: (R),CC2,CC3,CC4 Trap: Fixed-point overflow
IEWI-R
Condition code settings:
2 3 4 Resu
I
tin R
-
0 0 0 Zero
0 Nonzero
-
0 No fixed-point overflow
0
Fixed-point overflow (sign bit on)
52 Load/Store Instructions
If
CC2 is set to 1 and the fixed-point arithmetic trap mask
(AM) is a
1,
the BP traps to location X'43' after execution
of LOAD ABSOLUTE WORD; otherwise, the BP executes
the next instruction in sequence.
LCD
LOAD COMPLEMENT DOUBLEWORD
(Doubleword index alignment)
LOAD COMPLEMENT DOUBLEWORD forms the 64-bit
two's complement of the effective doubleword, loads the
32 low-order bits of the resu It into register Ru
1,
and then
loads the 32 high-order bits of the result into register R.
If R is an odd value, the result in register R is the 32 high-
order bits of the two's complemented doubleword. The con-
dition code settings are based on the two's complement of
the effective doubleword, rather than the final result in
register R.
Fixed-point overflow occurs if the effective doubleword is
_~3
(X'8000000000000000'), in which case the result in
registers Rand Ru1 is _~3 and CC2 is set to 1; otherwise,
CC2 is reset to O.
Affected: (R),(Rul),CC2, Trap: Fixed-point overflow
CC3,CC4
[-ED]32_63 - Ru1; [-ED] 0-31- R
Condition code settings:
2 3 4 Two's complement of effective doubleword
- 0 0 0 Zero
- 0 Negative
- 0 0 Positive
- 0
No fixed-point overflow
o
Fixed-point overflow
If
CC2 is set to 1 and the fixed-point arithmetic trap mask
(AM) is a 1, the BP traps to location X'43' after execution
of LOAD COMPLEMENT DOUBLEWORD; otherwise, the
BP executes the next instruction in sequence.
Example 1, even R field value:
ED
(R)
(Ru 1)
CC
Before executi on
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t=,""'nn
A
n""~""r-'
- /\ VIL..J"t..JU/07t-\O\...LJLr
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After execution
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