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## ANDS (immediate)

Bitwise AND (immediate), setting flags, performs a bitwise AND of a register value and an immediate value, and writes the result to the destination register. It updates the condition flags based on the result.

This instruction is used by the alias TST (immediate).

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
sf | 1 | 1 | 1 | 0 | 0 | 1 | 0 | 0 | N | immr | imms | Rn | Rd
| opc |  |  |  |  |  |

#### 32-bit (sf == 0 && N == 0)

ANDS <Wd>, <Wn>, #<imm>

#### 64-bit (sf == 1)

ANDS <Xd>, <Xn>, #<imm>

integer d = UInt(Rd); integer n = UInt(Rn); integer datasize = if sf == '1' then 64 else 32; bits(datasize) imm; if sf == '0' && N != '0' then UNDEFINED; (imm, -) = DecodeBitMasks(N, imms, immr, TRUE, datasize);

### Assembler Symbols

<Wd> | Is the 32-bit name of the general-purpose destination register, encoded in the "Rd" field.

<Wn> | Is the 32-bit name of the general-purpose source register, encoded in the "Rn" field.

<Xd> | Is the 64-bit name of the general-purpose destination register, encoded in the "Rd" field.

<Xn> | Is the 64-bit name of the general-purpose source register, encoded in the "Rn" field.

<imm> | For the 32-bit variant: is the bitmask immediate, encoded in "imms:immr".
| For the 64-bit variant: is the bitmask immediate, encoded in "N:imms:immr".

### Alias Conditions

Alias | Is preferred when
--- | ---
TST (immediate) | Rd == '11111'

### Operation

bits(datasize) result; bits(datasize) operand1 = X[n, datasize]; result = operand1 AND imm; PSTATE.<N,Z,C,V> = result<datasize-1>:IsZeroBit(result):'00'; X[d, datasize] = result;

### Operational information

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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