VEXT (multibyte elements)

Vector Extract extracts 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.

This is a pseudo-instruction of VEXT (byte elements). This means:

It has encodings from the following instruction sets: A32 ( A1 ) and T32 ( T1 ) .

A1

313029282726252423222120191817161514131211109876543210
111100101D11VnVdimm4NQM0Vm

64-bit SIMD vector (Q == 0)

VEXT{<c>}{<q>}.<size> {<Dd>,} <Dn>, <Dm>, #<imm>

is equivalent to

VEXT{<c>}{<q>}.8 {<Dd>,} <Dn>, <Dm>, #<imm*(size/8)>

128-bit SIMD vector (Q == 1)

VEXT{<c>}{<q>}.<size> {<Qd>,} <Qn>, <Qm>, #<imm>

is equivalent to

VEXT{<c>}{<q>}.8 {<Qd>,} <Qn>, <Qm>, #<imm*(size/8)>

T1

15141312111098765432101514131211109876543210
111011111D11VnVdimm4NQM0Vm

64-bit SIMD vector (Q == 0)

VEXT{<c>}{<q>}.<size> {<Dd>,} <Dn>, <Dm>, #<imm>

is equivalent to

VEXT{<c>}{<q>}.8 {<Dd>,} <Dn>, <Dm>, #<imm*(size/8)>

128-bit SIMD vector (Q == 1)

VEXT{<c>}{<q>}.<size> {<Qd>,} <Qn>, <Qm>, #<imm>

is equivalent to

VEXT{<c>}{<q>}.8 {<Qd>,} <Qn>, <Qm>, #<imm*(size/8)>

Assembler Symbols

<c>

For encoding A1: see Standard assembler syntax fields. This encoding must be unconditional.

For encoding T1: see Standard assembler syntax fields.

<q>

See Standard assembler syntax fields.

<size>

For the 64-bit SIMD vector variant: is the size of the operation, and can be one of 16 or 32.

For the 128-bit SIMD vector variant: is the size of the operation, and can be one of 16, 32 or 64.

<Qd>

Is the 128-bit name of the SIMD&FP destination register, encoded in the "D:Vd" field as <Qd>*2.

<Qn>

Is the 128-bit name of the first SIMD&FP source register, encoded in the "N:Vn" field as <Qn>*2.

<Qm>

Is the 128-bit name of the second SIMD&FP source register, encoded in the "M:Vm" field as <Qm>*2.

<Dd>

Is the 64-bit name of the SIMD&FP destination register, encoded in the "D:Vd" field.

<Dn>

Is the 64-bit name of the first SIMD&FP source register, encoded in the "N:Vn" field.

<Dm>

Is the 64-bit name of the second SIMD&FP source register, encoded in the "M:Vm" field.

<imm>

For the 64-bit SIMD vector variant: is the location of the extracted result in the concatenation of the operands, as a number of bytes from the least significant end, in the range 0 to (128/<size>)-1.

For the 128-bit SIMD vector variant: is the location of the extracted result in the concatenation of the operands, as a number of bytes from the least significant end, in the range 0 to (64/<size>)-1.

Operation

The description of VEXT (byte elements) gives the operational pseudocode for this instruction.


Internal version only: isa v01_31, pseudocode v2023-06_rel, sve v2023-06_rel ; Build timestamp: 2023-07-04T18:06

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