LDUMAXAB, LDUMAXALB, LDUMAXB, LDUMAXLB
Atomic unsigned maximum on byte in memory.
Xn|SP] ; Acquire general registers
Xn|SP] ; Acquire and release general registers
Xn|SP] ; No memory ordering general registers
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 32-bit name of the general-purpose register to be loaded.
- Is the 64-bit name of the general-purpose base register or stack pointer.
Supported in the Arm®v8.1 architecture and later.
Atomic unsigned maximum on byte in memory 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 unsigned numbers. The value initially loaded from memory is returned in the destination register.
- If the destination register is not
LDUMAXALBload from memory with acquire semantics.
LDUMAXALBstore to memory with release semantics.
LDUMAXBhas no memory ordering requirements.
For more information about memory ordering semantics see Load-Acquire, Store-Release in the Arm® Architecture Reference Manual Arm®v8, for Arm®v8‑A architecture profile.
For information about memory accesses see Load/Store addressing modes in the Arm® Architecture Reference Manual Arm®v8, for Arm®v8‑A architecture profile.