Add immediate value, setting flags
This instruction adds a register value and an optionally-shifted 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 CMN (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 | 0 | 1 | 1 | 0 | 0 | 0 | 1 | 0 | sh | imm12 | Rn | Rd | |||||||||||||||||||
| op | S | ||||||||||||||||||||||||||||||
let d : integer{} = UInt(Rd); let n : integer{} = UInt(Rn); let datasize : integer{} = 32 << UInt(sf); let imm : bits(24) = if sh == '0' then Zeros{12}::imm12 else imm12::Zeros{12};
| <Wd> |
Is the 32-bit name of the general-purpose destination register, encoded in the "Rd" field. |
| <Wn|WSP> |
Is the 32-bit name of the source general-purpose register or stack pointer, encoded in the "Rn" field. |
| <imm> |
Is an unsigned immediate, in the range 0 to 4095, encoded in the "imm12" field. |
| <shift> |
Is the optional left shift to apply to the immediate, defaulting to LSL #0 and
encoded in
|
| <Xd> |
Is the 64-bit name of the general-purpose destination register, encoded in the "Rd" field. |
| <Xn|SP> |
Is the 64-bit name of the source general-purpose register or stack pointer, encoded in the "Rn" field. |
| Alias | Is preferred when |
|---|---|
| CMN (immediate) | Rd == '11111' |
let operand1 : bits(datasize) = if n == 31 then SP{datasize}() else X{datasize}(n); let operand2 : bits(datasize) = ZeroExtend{}(imm); var result : bits(datasize); var nzcv : bits(4); (result, nzcv) = AddWithCarry{datasize}(operand1, operand2, '0'); X{datasize}(d) = result; PSTATE.[N,Z,C,V] = nzcv;
This instruction is a data-independent-time instruction as described in About PSTATE.DIT.
2026-03_rel 2026-03-26 20:48:11
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