Intel Itanium 9150M, Manual, Page: 251 / 420

3:242 Volume 3: Instruction Reference
setf
setf — Set Floating-point Value, Exponent, or Significand
Format: (
qp
) setf.s
f
1
=
r
2
single_form M18
(
qp
) setf.d
f
1
=
r
2
double_form M18
(
qp
) setf.exp
f
1
=
r
2
exponent_form M18
(
qp
) setf.sig
f
1
=
r
2
significand_form M18
Description:
In the single and double forms, GR r
2
is treated as a single precision (in the
single_form) or double precision (in the double_form) memory representation,
converted into floating-point register format, and placed in FR
f
1
, as shown in Figure 5-4
and Figure 5-5 on page 1:93 , respectively.
In the exponent_form, bits 16:0 of GR
r
2
are copied to the exponent field of FR
f
1
and bit
17 of GR r
2
is copied to the sign bit of FR f
1
. The significand field of FR f
1
is set to one
(0x800...000).
In the significand_form, the value in GR
r
2
is copied to the significand field of FR
f
1
.
The exponent field of FR
f
1
is set to the biased exponent for 2.0
63
(0x1003E) and the
sign field of FR
f
1
is set to positive (0).
For all forms, if the NaT bit corresponding to
r
2
is equal to 1, FR
f
1
is set to NaTVal
instead of the computed result.
Figure 2-41. Function of setf.exp
Figure 2-42. Function of setf.sig
1000 exponent s FR f
1
GR r
1
0 18 17
000
. . .
63
significand 0x1003E 0 FR f
1
GR r
1
0 63