Atomic bit clear on byte in memory, without return, atomically loads an 8-bit byte from memory, performs a bitwise AND with the complement of the value held in a register on it, and stores the result back to memory.
For information about addressing modes, see Load/Store addressing modes.
This is an alias of LDCLRB, LDCLRAB, LDCLRALB, LDCLRLB. This means:
| 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 | 0 | 0 | 0 | R | 1 | Rs | 0 | 0 | 0 | 1 | 0 | 0 | Rn | 1 | 1 | 1 | 1 | 1 | ||||||||
| size | VR | A | o3 | opc | Rt | ||||||||||||||||||||||||||
| <Ws> |
Is the 32-bit name of the general-purpose register holding the data value to be operated on with the contents of the memory location, encoded in the "Rs" field. |
| <Xn|SP> |
Is the 64-bit name of the general-purpose base register or stack pointer, encoded in the "Rn" field. |
The description of LDCLRB, LDCLRAB, LDCLRALB, LDCLRLB gives the operational pseudocode for this instruction.
If PSTATE.DIT is 1, the timing of this instruction is insensitive to the value of the data being loaded or stored.
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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