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

## CMP<cc> (immediate)

Compare vector to immediate

Compare active integer elements in the source vector with an immediate, and place the boolean results of the specified comparison in the corresponding elements of the destination predicate. Inactive elements in the destination predicate register are set to zero. Sets the First (N), None (Z), !Last (C) condition flags based on the predicate result, and the V flag to zero.

<cc> | Comparison
--- | ---
EQ | equal
GE | signed greater than or equal
GT | signed greater than
HI | unsigned higher than
HS | unsigned higher than or same
LE | signed less than or equal
LO | unsigned lower than
LS | unsigned lower than or same
LT | signed less than
NE | not equal

It has encodings from 10 classes: Equal , Greater than , Greater than or equal , Higher , Higher or same , Less than , Less than or equal , Lower , Lower or same and Not equal

### Equal

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 | size | 0 | imm5 | 1 | 0 | 0 | Pg | Zn | 0 | Pd
|  |  |  |  |  |  |  |  | ne |

####

CMPEQ <Pd>.<T>, <Pg>/Z, <Zn>.<T>, #<imm>

if !HaveSVE() && !HaveSME() then UNDEFINED; constant integer esize = 8 << UInt(size); integer g = UInt(Pg); integer n = UInt(Zn); integer d = UInt(Pd); SVECmp op = Cmp_EQ; integer imm = SInt(imm5); boolean unsigned = FALSE;

### Greater than

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 | size | 0 | imm5 | 0 | 0 | 0 | Pg | Zn | 1 | Pd
|  |  |  |  |  | lt |  |  | ne |

####

CMPGT <Pd>.<T>, <Pg>/Z, <Zn>.<T>, #<imm>

if !HaveSVE() && !HaveSME() then UNDEFINED; constant integer esize = 8 << UInt(size); integer g = UInt(Pg); integer n = UInt(Zn); integer d = UInt(Pd); SVECmp op = Cmp_GT; integer imm = SInt(imm5); boolean unsigned = FALSE;

### Greater than or equal

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 | size | 0 | imm5 | 0 | 0 | 0 | Pg | Zn | 0 | Pd
|  |  |  |  |  | lt |  |  | ne |

####

CMPGE <Pd>.<T>, <Pg>/Z, <Zn>.<T>, #<imm>

if !HaveSVE() && !HaveSME() then UNDEFINED; constant integer esize = 8 << UInt(size); integer g = UInt(Pg); integer n = UInt(Zn); integer d = UInt(Pd); SVECmp op = Cmp_GE; integer imm = SInt(imm5); boolean unsigned = FALSE;

### Higher

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 | 0 | size | 1 | imm7 | 0 | Pg | Zn | 1 | Pd
|  |  |  | lt |  |  | ne |

####

CMPHI <Pd>.<T>, <Pg>/Z, <Zn>.<T>, #<imm>

if !HaveSVE() && !HaveSME() then UNDEFINED; constant integer esize = 8 << UInt(size); integer g = UInt(Pg); integer n = UInt(Zn); integer d = UInt(Pd); SVECmp op = Cmp_GT; integer imm = UInt(imm7); boolean unsigned = TRUE;

### Higher or same

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 | 0 | size | 1 | imm7 | 0 | Pg | Zn | 0 | Pd
|  |  |  | lt |  |  | ne |

####

CMPHS <Pd>.<T>, <Pg>/Z, <Zn>.<T>, #<imm>

if !HaveSVE() && !HaveSME() then UNDEFINED; constant integer esize = 8 << UInt(size); integer g = UInt(Pg); integer n = UInt(Zn); integer d = UInt(Pd); SVECmp op = Cmp_GE; integer imm = UInt(imm7); boolean unsigned = TRUE;

### Less than

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 | size | 0 | imm5 | 0 | 0 | 1 | Pg | Zn | 0 | Pd
|  |  |  |  |  | lt |  |  | ne |

####

CMPLT <Pd>.<T>, <Pg>/Z, <Zn>.<T>, #<imm>

if !HaveSVE() && !HaveSME() then UNDEFINED; constant integer esize = 8 << UInt(size); integer g = UInt(Pg); integer n = UInt(Zn); integer d = UInt(Pd); SVECmp op = Cmp_LT; integer imm = SInt(imm5); boolean unsigned = FALSE;

### Less than or equal

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 | size | 0 | imm5 | 0 | 0 | 1 | Pg | Zn | 1 | Pd
|  |  |  |  |  | lt |  |  | ne |

####

CMPLE <Pd>.<T>, <Pg>/Z, <Zn>.<T>, #<imm>

if !HaveSVE() && !HaveSME() then UNDEFINED; constant integer esize = 8 << UInt(size); integer g = UInt(Pg); integer n = UInt(Zn); integer d = UInt(Pd); SVECmp op = Cmp_LE; integer imm = SInt(imm5); boolean unsigned = FALSE;

### Lower

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 | 0 | size | 1 | imm7 | 1 | Pg | Zn | 0 | Pd
|  |  |  | lt |  |  | ne |

####

CMPLO <Pd>.<T>, <Pg>/Z, <Zn>.<T>, #<imm>

if !HaveSVE() && !HaveSME() then UNDEFINED; constant integer esize = 8 << UInt(size); integer g = UInt(Pg); integer n = UInt(Zn); integer d = UInt(Pd); SVECmp op = Cmp_LT; integer imm = UInt(imm7); boolean unsigned = TRUE;

### Lower or same

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 | 0 | size | 1 | imm7 | 1 | Pg | Zn | 1 | Pd
|  |  |  | lt |  |  | ne |

####

CMPLS <Pd>.<T>, <Pg>/Z, <Zn>.<T>, #<imm>

if !HaveSVE() && !HaveSME() then UNDEFINED; constant integer esize = 8 << UInt(size); integer g = UInt(Pg); integer n = UInt(Zn); integer d = UInt(Pd); SVECmp op = Cmp_LE; integer imm = UInt(imm7); boolean unsigned = TRUE;

### Not equal

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 | size | 0 | imm5 | 1 | 0 | 0 | Pg | Zn | 1 | Pd
|  |  |  |  |  |  |  |  | ne |

####

CMPNE <Pd>.<T>, <Pg>/Z, <Zn>.<T>, #<imm>

if !HaveSVE() && !HaveSME() then UNDEFINED; constant integer esize = 8 << UInt(size); integer g = UInt(Pg); integer n = UInt(Zn); integer d = UInt(Pd); SVECmp op = Cmp_NE; integer imm = SInt(imm5); boolean unsigned = FALSE;

### Assembler Symbols

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

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

<Pg> | Is the name of the governing scalable predicate register P0-P7, encoded in the "Pg" field.

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

<imm> | For the equal, greater than, greater than or equal, less than, less than or equal and not equal variant: is the signed immediate operand, in the range -16 to 15, encoded in the "imm5" field.
| For the higher, higher or same, lower and lower or same variant: is the unsigned immediate operand, in the range 0 to 127, encoded in the "imm7" field.

### Operation

CheckSVEEnabled(); constant integer VL = CurrentVL; constant integer PL = VL DIV 8; constant integer elements = VL DIV esize; bits(PL) mask = P[g, PL]; bits(VL) operand1 = if AnyActiveElement(mask, esize) then Z[n, VL] else Zeros(VL); bits(PL) result; constant integer psize = esize DIV 8; for e = 0 to elements-1 integer element1 = Int(Elem[operand1, e, esize], unsigned); if ActivePredicateElement(mask, e, esize) then boolean cond; case op of when Cmp_EQ cond = element1 == imm; when Cmp_NE cond = element1 != imm; when Cmp_GE cond = element1 >= imm; when Cmp_LT cond = element1 < imm; when Cmp_GT cond = element1 > imm; when Cmp_LE cond = element1 <= imm; bit pbit = if cond then '1' else '0'; Elem[result, e, psize] = ZeroExtend(pbit, psize); else Elem[result, e, psize] = ZeroExtend('0', psize); 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.

If FEAT_SME is implemented and the PE is in Streaming SVE mode, then any subsequent instruction which is dependent on the predicate register or NZCV condition flags written by this instruction might be significantly delayed.

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

Internal version only: isa v33.74, AdvSIMD v29.23, pseudocode v2023-09_rel, sve v2023-09_rc3 ; Build timestamp: 2023-09-27T17:06

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