VEXT

VEXT (Vector Extract) extracts 8-bit elements from the bottom end of the second operand vector and the top end of the first, concatenates them, and places the result in the destination vector. See Figure 6 for an example.

Figure 6. Operation of doubleword VEXT for imm = 3

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Show/hideSyntax

VEXT{cond}.8 {Qd}, Qn, Qm, #imm
VEXT{cond}.8 {Dd}, Dn, Dm, #imm

where:

cond

is an optional condition code.

Qd, Qn, Qm

specifies the destination register, the first operand register, and the second operand register, for a quadword operation.

Dd, Dn, Dm

specifies the destination register, the first operand register, and the second operand register, for a doubleword operation.

imm

is the number of 8-bit elements to extract from the bottom of the second operand vector, in the range 0-7 for doubleword operations, or 0-15 for quadword operations.

Show/hideVEXT pseudo-instruction

You can specify a datatype of 16, 32, or 64 instead of 8. In this case, #imm refers to halfwords, words, or doublewords instead of referring to bytes, and the permitted ranges are correspondingly reduced.

Show/hideSee also

Reference:
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