STLRB

Store-release register byte

This instruction 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. For information about addressing modes, see Load/Store addressing modes.

Encoding: No offset

313029282726252423222120191817161514131211109876543210
00001000100(1)(1)(1)(1)(1)1(1)(1)(1)(1)(1)
sizeLRso0Rt2RnRt

STLRB <Wt>, [<Xn|SP>{, #0}]

Decoding algorithm

constant integer t = UInt(Rt);
constant integer n = UInt(Rn);
constant boolean tagchecked = n != 31;

Operation

bits(64) address;

constant AccessDescriptor accdesc = CreateAccDescAcqRel(MemOp_STORE, tagchecked);

if n == 31 then
    CheckSPAlignment();
    address = SP[64];
else
    address = X[n, 64];

Mem[address, 1, accdesc] = X[t, 8];

Explanations

<Wt>: Is the 32-bit name of the general-purpose register to be transferred, encoded in the "Rt" field.
<Xn|SP>: Is the 64-bit name of the general-purpose base register or stack pointer, encoded in the "Rn" field.

Operational Notes

If PSTATE.DIT is 1, the timing of this instruction is insensitive to the value of the data being loaded or stored.