Conditional Compare (immediate) sets the value of the condition flags to the result of the comparison of a register value and an immediate 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 | 1 | 1 | 1 | 1 | 0 | 1 | 0 | 0 | 1 | 0 | imm5 | cond | 1 | 0 | Rn | 0 | nzcv | ||||||||||||||
| op | |||||||||||||||||||||||||||||||
integer n = UInt(Rn); integer datasize = if sf == '1' then 64 else 32; boolean sub_op = (op == '1'); bits(4) condition = cond; bits(4) flags = nzcv; bits(datasize) imm = ZeroExtend(imm5, datasize);
| <Wn> |
Is the 32-bit name of the first general-purpose source register, encoded in the "Rn" field. |
| <Xn> |
Is the 64-bit name of the first general-purpose source register, encoded in the "Rn" field. |
| <imm> |
Is a five bit unsigned (positive) immediate encoded in the "imm5" 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 "cond" field in the standard way. |
if ConditionHolds(condition) then bits(datasize) operand1 = X[n]; bits(datasize) operand2 = imm; bit carry_in = '0'; if sub_op then operand2 = NOT(operand2); carry_in = '1'; (-, flags) = AddWithCarry(operand1, operand2, carry_in); PSTATE.<N,Z,C,V> = flags;
If PSTATE.DIT is 1:
Internal version only: isa v33.11seprel, AdvSIMD v29.05, pseudocode v2021-09_rel, sve v2021-09_rc3d ; Build timestamp: 2021-10-06T11:41
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