Vector Unit Registers; Vu Register Format; Vu Register Addressing; Computational Instructions - Nintendo Ultra64 Programmer's Manual

RSP Architecture

Vector Unit Registers

element 0
byte 0 byte 1 byte 2 byte 3 byte 4 byte 5 byte 6 byte 7 byte 8 byte 9 byte 10 byte 11 byte 12 byte 13 byte 14 byte 15
127
34
The RSP Vector Unit has 32 general-purpose vector registers, each 128 bits
wide.
Depending on the operation, vector registers can be accessed as a single unit,
by bytes, or by 16-bit elements corresponding to a vector slice.

VU Register Format

The RSP has big-endian byte ordering.
Figure 2-3
element 1 element 2 element 3
Bits within a byte or register element are numbered similarly, little-endian.

VU Register Addressing

VU registers can be accessed in a variety of formats, depending on the
instruction being executed.

Computational Instructions

Most computational instructions operate on VU registers as vectors,
performing the same operation on 8 16-bit vector elements, on an
element-by-element basis, with the 8 elements corresponding to the vector
slices.
VU Register Format
element 4 element 5 element 6 element 7
0