LDUMAXAH, LDUMAXALH, LDUMAXH, LDUMAXLH
Atomic unsigned maximum on halfword 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 ARMv8.1 and later.
Atomic unsigned maximum on halfword in memory atomically loads a 16-bit halfword 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
LDUMAXALHload from memory with acquire semantics.
LDUMAXALHstore to memory with release semantics.
LDUMAXHhas no memory ordering requirements.
For more information about memory ordering semantics see Load-Acquire, Store-Release in the ARMv8-A Architecture Reference Manual.
For information about memory accesses see Load/Store addressing modes in the ARMv8-A Architecture Reference Manual.