Evaluation of 8-bit or 16-bit flag values
This instruction sets the PSTATE.NZV flags based on the value in the specified general-purpose register. SETF8 treats the value as an 8-bit value. SETF16 treats the value as a 16-bit value.
The PSTATE.C flag is not affected by these instructions.
| 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 | 1 | 1 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | sz | 0 | 0 | 1 | 0 | Rn | 0 | 1 | 1 | 0 | 1 | ||||
| sf | op | S | opcode2 | o3 | mask | ||||||||||||||||||||||||||
if !IsFeatureImplemented(FEAT_FlagM) then EndOfDecode(Decode_UNDEF); end; let size : integer{} = 8 << UInt(sz); let n : integer = UInt(Rn);
let reg : bits(32) = X{}(n); PSTATE.N = reg[size-1]; PSTATE.Z = if (reg[size-1:0] == Zeros{size}) then '1' else '0'; PSTATE.V = reg[size] XOR reg[size-1]; //PSTATE.C unchanged;
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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