Store-Release Register Byte.
Is the 32-bit name of the general-purpose register to be transferred.
Is the 64-bit name of the general-purpose base register or stack pointer.
Store-Release Register Byte stores a byte from a 32-bit register to a memory location. The instruction also has memory ordering semantics as described in 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.