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RCWSCLR, RCWSCLRA, RCWSCLRAL, RCWSCLRL

Read check write software atomic bit clear on doubleword in memory

This instruction atomically loads a 64-bit doubleword from memory, performs a bitwise AND with the complement of the value held in a register on it, and conditionally stores the result back to memory. Storing of the result back to memory is conditional on RCW Checks and RCWS Checks. The value initially loaded from memory is returned in the destination register. This instruction updates the condition flags based on the result of the update of memory.

• If the destination register is not XZR, RCWSCLRA and RCWSCLRAL load from memory with acquire semantics.
• RCWSCLRL and RCWSCLRAL store to memory with release semantics.
• RCWSCLR has neither acquire nor release semantics.

Integer
(FEAT_THE)

Decode for all variants of this encoding

if !IsFeatureImplemented(FEAT_THE) then EndOfDecode(Decode_UNDEF); end; let s : integer{} = UInt(Rs); let t : integer{} = UInt(Rt); let n : integer{} = UInt(Rn); let soft : boolean = TRUE; let acquire : boolean = A == '1' && t != 31; let release : boolean = R == '1'; let tagchecked : boolean = n != 31;