Base Instructions | SIMD&FP Instructions | SVE Instructions | SME Instructions | Index by Encoding | Shared Pseudocode | Proprietary Notice

## LSR (wide elements, unpredicated)

Logical shift right by 64-bit wide elements (unpredicated)

Shift right, inserting zeroes, all elements of the first source vector by corresponding overlapping 64-bit elements of the second source vector and place the first in the corresponding elements of the destination vector. The shift amount is a vector of unsigned 64-bit doubleword elements in which all bits are significant, and not used modulo the destination element size. This instruction is unpredicated.

31 | 30 | 29 | 28 | 27 | 26 | 25 | 24 | 23 | 22 | 21 | 20 | 19 | 18 | 17 | 16 | 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0
0 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | size | 1 | Zm | 1 | 0 | 0 | 0 | 0 | 1 | Zn | Zd
|  |  |  |  |  | U |  |

####

LSR <Zd>.<T>, <Zn>.<T>, <Zm>.D

if !HaveSVE() && !HaveSME() then UNDEFINED; if size == '11' then UNDEFINED; constant integer esize = 8 << UInt(size); integer n = UInt(Zn); integer m = UInt(Zm); integer d = UInt(Zd);

### Assembler Symbols

<Zd> | Is the name of the destination scalable vector register, encoded in the "Zd" field.

<T> | Is the size specifier, encoded in size:
size | <T>
--- | ---
00 | B
01 | H
10 | S
11 | RESERVED

<Zn> | Is the name of the first source scalable vector register, encoded in the "Zn" field.

<Zm> | Is the name of the second source scalable vector register, encoded in the "Zm" field.

### Operation

CheckSVEEnabled(); constant integer VL = CurrentVL; constant integer PL = VL DIV 8; constant integer elements = VL DIV esize; bits(VL) operand1 = Z[n, VL]; bits(VL) operand2 = Z[m, VL]; bits(VL) result; for e = 0 to elements-1 bits(esize) element1 = Elem[operand1, e, esize]; bits(64) element2 = Elem[operand2, (e * esize) DIV 64, 64]; integer shift = Min(UInt(element2), esize); Elem[result, e, esize] = LSR(element1, shift); Z[d, VL] = result;

### Operational information

If FEAT_SVE2 is implemented or FEAT_SME is implemented, then if PSTATE.DIT is 1:

- The execution time of this instruction is independent of:
  - The values of the data supplied in any of its registers.
  - The values of the NZCV flags.
- The response of this instruction to asynchronous exceptions does not vary based on:
  - The values of the data supplied in any of its registers.
  - The values of the NZCV flags.

Base Instructions | SIMD&FP Instructions | SVE Instructions | SME Instructions | Index by Encoding | Shared Pseudocode | Proprietary Notice

Internal version only: isa v33.64, AdvSIMD v29.12, pseudocode v2023-06_rel, sve v2023-06_rel ; Build timestamp: 2023-07-04T19:42

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