Revision 1.0
Vector Unit Registers
37
The low 8 bits are used for most compares (
vlt, veq, vne, vge
) and
merge (
vmrg
), and all 16 bits are used for the clip compares (
vcl, vch,
vcr
).
Figure 2-5
VCC Register Format
Vector Carry Out Register (VCO)
This 16-bit register contains 2 bits per 16-bit slice of the VU and is used by
some of the add and select instructions to perform double-precision
operations.
The low 8 bits are
CARRY
, and are set by
vaddc
or
vsubc
instructions that
generate a carry out (or borrow, in the case of
vsubc
). The upper 8 bits are
NOT EQUAL
, set by
vaddc
or
vsubc
if the operands are not equal.
vadd
,
vsub
, and select compare instructions (
vlt, veq, vne, vge
) use
VCO as inputs and clear VCO. Select compare instructions use VCO which
was previously set by a
vsubc
instruction.
Figure 2-6
VCO Register Format
0
elem
7
elem
6
elem
5
elem
4
elem
3
elem
2
elem
1
elem
0
elem
7
elem
6
elem
5
elem
4
elem
3
elem
2
elem
1
elem
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
vs
<=
-vt
(for clip compares)
select compare is TRUE
(
vs
>=
vt
, for clip compares)
0
elem
7
elem
6
elem
5
elem
4
elem
3
elem
2
elem
1
elem
0
elem
7
elem
6
elem
5
elem
4
elem
3
elem
2
elem
1
elem
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
NOT EQUAL is TRUE
CARRY is TRUE
Summary of Contents for Ultra64
Page 2: ...2 ...
Page 10: ...10 ...
Page 12: ...12 Figure 6 2 buildtask Operation 137 ...
Page 14: ...14 ...
Page 80: ...80 Vector Unit Instructions vmadm dres_int dres_int vconst 3 vmadn dres_frac vconst vconst 0 ...
Page 104: ...104 RSP Coprocessor 0 ...
Page 150: ...150 Advanced Information ...
Page 155: ...Revision 1 0 155 ...
Page 248: ...248 Exceptions None ...
Page 251: ...Revision 1 0 251 Exceptions None ...
Page 254: ...254 Exceptions None ...
Page 257: ...Revision 1 0 257 Exceptions None ...
Page 293: ...Revision 1 0 293 Exceptions None ...
Page 316: ...316 Exceptions None ...