Intel Itanium 9150M, Manual

Page: 233 / 420

3:224 Volume 3: Instruction Reference
pshr
pshr — Parallel Shift Right
Format: (
qp
) pshr2
r
1
=
r
3
,
r
2
signed_form, two_byte_form, variable_form I5
(
qp
) pshr2
r
1
=
r
3
, count
5
signed_form, two_byte_form, fixed_form I6
(
qp
) pshr2.u
r
1
=
r
3
,
r
2
unsigned_form, two_byte_form, variable_form I5
(
qp
) pshr2.u
r
1
=
r
3
, count
5
unsigned_form, two_byte_form, fixed_form I6
(
qp
) pshr4
r
1
=
r
3
,
r
2
signed_form, four_byte_form, variable_form I5
(
qp
) pshr4
r
1
=
r
3
, count
5
signed_form, four_byte_form, fixed_form I6
(
qp
) pshr4.u
r
1
=
r
3
,
r
2
unsigned_form, four_byte_form, variable_form I5
(
qp
) pshr4.u
r
1
=
r
3
, count
5
unsigned_form, four_byte_form, fixed_form I6
Description:
The data elements of GR
r
3
are each independently shifted to the right by the scalar
shift count in GR
r
2
, or in the immediate field count
5
. The high-order bits of each
element are filled with either the initial value of the sign bits of the data elements in GR
r
3
(arithmetic shift) or zeros (logical shift). The shift count is interpreted as unsigned.
Shift counts greater than 15 (for 16-bit quantities) or 31 (for 32-bit quantities) yield all
zero or all one results depending on the initial values of the sign bits of the data
elements in GR
r
3
and whether a signed or unsigned shift is done. The results are placed
in GR
r
1
.