Technical data

Vector Processing Concepts
1.8 GATHER AND SCATTER INSTRUCTIONS
To support random-strided vectors, gather and scatter instructions operate
under control of a vector register that contains an index vector. For each
element in the vector, the corresponding element in the index vector
contains an offset from the start location of the vector in memory. The
gather instruction uses these offsets to "load" the vector elements into the
destination register, and the scatter instruction uses them to "store" the
vector elements back into memory (see Figure 1–7).
Figure 1–7 Vector Gather and Scatter Instructions
msb-0426-90
OFFSET1
OFFSET2
OFFSET3
OFFSET4
1ST ELT
2ND ELT
3RD ELT
4TH ELT
1ST ELT
2ND ELT
3RD ELT
4TH ELT
BASE +
OFFSET1
BASE +
OFFSET2
BASE +
OFFSET3
BASE +
OFFSET4
VECTOR
REGISTER
VECTOR IN
MEMORY
VECTOR REGISTER
WITH OFFSETS
MEMORY ADDRESS SELECT
LOAD/STORE PATH
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