Atomic bit clear on word or doubleword in memory, without return, atomically loads a 32-bit word or 64-bit doubleword 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 memory accesses see Load/Store addressing modes.
This is an alias of LDCLR, LDCLRA, LDCLRAL, LDCLRL. 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 |
| 1 | x | 1 | 1 | 1 | 0 | 0 | 0 | 0 | R | 1 | Rs | 0 | 0 | 0 | 1 | 0 | 0 | Rn | 1 | 1 | 1 | 1 | 1 | ||||||||
| size | A | opc | Rt | ||||||||||||||||||||||||||||
is equivalent to
and is always the preferred disassembly.
is equivalent to
and is always the preferred disassembly.
| <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. |
| <Xs> |
Is the 64-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 LDCLR, LDCLRA, LDCLRAL, LDCLRL 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: isa v33.11seprel, AdvSIMD v29.05, pseudocode v2021-09_rel, sve v2021-09_rc3d ; Build timestamp: 2021-10-06T11:41
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