MIPS R4000 Microprocessor User's Manual 165
Floating-Point Unit
For single- and double-precision formats, the value of a number, v, is
determined by the equations shown in Table 6-5.
Table 6-5 Equations for Calculating Values in Single and Double-Precision
Floating-Point Format
For all floating-point formats, if v is NaN, the most-significant bit of f
determines whether the value is a signaling or quiet NaN: v is a signaling
NaN if the most-significant bit of f is set, otherwise, v is a quiet NaN.
Table 6-6 defines the values for the format parameters; minimum and
maximum floating-point values are given in Table 6-7.
Table 6-6 Floating-Point Format Parameter Values
No. Equation
(1) if E = E
max
+1 and
f
≠ 0, then
v
is NaN, regardless of
s
(2) if E = E
max
+1 and f = 0, then
v
= (–1)
s
∞
(3) if E
min
≤ E ≤ E
max
, then
v
= (–1)
s
2
E
(1
.f
)
(4) if E = E
min
–1 and f ≠ 0, then
v
= (–1)
s
2
Emin
(0
.f
)
(5) if E = E
min
–1 and f = 0, then
v
= (–1)
s
0
Parameter
Format
Single Double
E
max
+127 +1023
E
min
–126 –1022
Exponent
bias
+127 +1023
Exponent width in bits 8 11
Integer bit hidden hidden
f (Fraction width in bits) 24 53
Format width in bits 32 64
To Next Page
Loading...