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

## EOR (predicates)

Bitwise exclusive OR predicates

Bitwise exclusive OR active elements of the second source predicate with corresponding elements of the first source predicate and place the results in the corresponding elements of the destination predicate. Inactive elements in the destination predicate register are set to zero. Does not set the condition flags.

This instruction is used by the alias NOT (predicate).

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 | 1 | 0 | 0 | 1 | 0 | 1 | 0 | 0 | 0 | 0 | Pm | 0 | 1 | Pg | 1 | Pn | 0 | Pd
|  | S |  |  |  |  |  |  |  |

####

EOR <Pd>.B, <Pg>/Z, <Pn>.B, <Pm>.B

if !IsFeatureImplemented(FEAT_SVE) && !IsFeatureImplemented(FEAT_SME) then UNDEFINED; constant integer esize = 8; constant integer g = UInt(Pg); constant integer n = UInt(Pn); constant integer m = UInt(Pm); constant integer d = UInt(Pd); constant boolean setflags = FALSE;

### Assembler Symbols

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

<Pg> | Is the name of the governing scalable predicate register, encoded in the "Pg" field.

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

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

### Alias Conditions

Alias | Is preferred when
--- | ---
NOT (predicate) | Pm == Pg

### Operation

CheckSVEEnabled(); constant integer VL = CurrentVL; constant integer PL = VL DIV 8; constant integer elements = VL DIV esize; constant bits(PL) mask = P[g, PL]; constant bits(PL) operand1 = P[n, PL]; constant bits(PL) operand2 = P[m, PL]; bits(PL) result; constant integer psize = esize DIV 8; for e = 0 to elements-1 constant bit element1 = PredicateElement(operand1, e, esize); constant bit element2 = PredicateElement(operand2, e, esize); if ActivePredicateElement(mask, e, esize) then Elem[result, e, psize] = ZeroExtend(element1 EOR element2, psize); else Elem[result, e, psize] = ZeroExtend('0', psize); if setflags then PSTATE.<N,Z,C,V> = PredTest(mask, result, esize); P[d, PL] = 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 operand registers when its governing predicate register contains the same value for each execution.
  - 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 operand registers when its governing predicate register contains the same value for each execution.
  - 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: aarchmrs v2024-03_relA, pseudocode v2024-03_rel, sve v2024-03_rel ; Build timestamp: 2024-03-26T09:45

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