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INSTRUCTION SET REFERENCE
FADD/FADDP/FIADDAdd (Continued)
.
NOTES:
FMeans finite-real number.
IMeans integer.
*Indicates floating-point invalid-arithmetic-operand (#IA) exception.
Operation
IF instruction is FIADD
THEN
DEST
<
DEST + ConvertExtendedReal(SRC);
ELSE (* source operand is real number *)
DEST
<
DEST + SRC;
FI;
IF instruction = FADDP
THEN
PopRegisterStack;
FI;
FPU Flags Affected
C1
Set to 0 if stack underflow occurred.
Indicates rounding direction if the inexact result exception (#P) is gener-
ated: 0 = not roundup; 1 = roundup.
C0, C2, C3
Undefined.
DEST
??
?
F
?
0
+
0
+
F
+
?
NaN
-
?
-
?
-
?
-
?
-
?
-
?
*NaN
?
F or
?
I-
?
?
FSRCSRC
±
F or
±
0
+
?
NaN
SRC
?
0
-
?
DEST
?
0
±
0DEST
+
?
NaN
+
0
-
?
DEST
±
0
+0DEST
+
?
NaN
+
F or +I-
¥
F or
±
0SRCSRC
+
F
+
?
NaN
+
?
*
+
?
+
?
+
?
+
?
+
?
NaN
NaNNaNNaNNaNNaNNaNNaNNaN