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## CCMN (register)

Conditional Compare Negative (register) sets the value of the condition flags to the result of the comparison of a register value and the inverse of another register value if the condition is TRUE, and an immediate value otherwise.

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 | 0 | 1 | 1 | 1 | 0 | 1 | 0 | 0 | 1 | 0 | Rm | cond | 0 | 0 | Rn | 0 | nzcv
| op | S |  |  |  |  | o2 |  | o3 |

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

CCMN <Wn>, <Wm>, #<nzcv>, <cond>

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

CCMN <Xn>, <Xm>, #<nzcv>, <cond>

integer n = UInt(Rn); integer m = UInt(Rm); constant integer datasize = 32 << UInt(sf); bits(4) condition = cond; bits(4) flags = nzcv;

### Assembler Symbols

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

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

<nzcv> | Is the flag bit specifier, an immediate in the range 0 to 15, giving the alternative state for the 4-bit NZCV condition flags, encoded in the "nzcv" field.

<cond> | Is one of the standard conditions, encoded in the standard way, and encoded in cond:
cond | <cond>
--- | ---
0000 | EQ
0001 | NE
0010 | CS
0011 | CC
0100 | MI
0101 | PL
0110 | VS
0111 | VC
1000 | HI
1001 | LS
1010 | GE
1011 | LT
1100 | GT
1101 | LE
1110 | AL
1111 | NV

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

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

### Operation

if ConditionHolds(condition) then bits(datasize) operand1 = X[n, datasize]; bits(datasize) operand2 = X[m, datasize]; (-, flags) = AddWithCarry(operand1, operand2, '0'); PSTATE.<N,Z,C,V> = flags;

### 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: aarchmrs v2024-03_relA, pseudocode v2024-03_rel, sve v2024-03_rel ; Build timestamp: 2024-03-26T09:45

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