Compare Negative (register-shifted register) adds a register value and a register-shifted register value. It updates the condition flags based on the result, and discards the result.
| 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 |
| != 1111 | 0 | 0 | 0 | 1 | 0 | 1 | 1 | 1 | Rn | (0) | (0) | (0) | (0) | Rs | 0 | stype | 1 | Rm | |||||||||||||
| cond | |||||||||||||||||||||||||||||||
constant n = UInt(Rn); constant m = UInt(Rm); constant s = UInt(Rs); constant shift_t = DecodeRegShift(stype); if n == 15 || m == 15 || s == 15 then UNPREDICTABLE;
For more information about the constrained unpredictable behavior, see Architectural Constraints on UNPREDICTABLE behaviors.
| <c> |
| <q> |
| <Rn> |
Is the first general-purpose source register, encoded in the "Rn" field. |
| <Rm> |
Is the second general-purpose source register, encoded in the "Rm" field. |
| <type> |
Is the type of shift to be applied to the second source register,
encoded in
|
| <Rs> |
Is the third general-purpose source register holding a shift amount in its bottom 8 bits, encoded in the "Rs" field. |
if ConditionPassed() then EncodingSpecificOperations(); constant shift_n = UInt(R[s]<7:0>); constant shifted = Shift(R[m], shift_t, shift_n, PSTATE.C); constant (result, nzcv) = AddWithCarry(R[n], shifted, '0'); PSTATE.<N,Z,C,V> = nzcv;
If CPSR.DIT is 1, this instruction has passed its condition execution check, and does not use R15 as either its source or destination:
Internal version only: isa v01_32, pseudocode v2024-12_rel ; Build timestamp: 2024-12-16T10:54
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