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Atomic signed maximum on byte in memory, without return.


STSMAXB Ws, [Xn|SP] ; No memory ordering general registers

STSMAXLB Ws, [Xn|SP] ; Release general registers


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.
Is the 64-bit name of the general-purpose base register or stack pointer.

Architectures supported

Supported in ARMv8.1 and later.


Atomic signed maximum on byte in memory, without return, atomically loads an 8-bit byte from memory, compares it against the value held in a register, and stores the larger value back to memory, treating the values as signed numbers.

  • STSMAXB has no memory ordering semantics.
  • STSMAXLB stores to memory with release semantics, as described in Load-Acquire, Store-Release.

For information about memory accesses see Load/Store addressing modes in the ARM Architecture Reference Manual ARMv8, for ARMv8-A architecture profile.