STURB

Store Register Byte (unscaled) calculates an address from a base register value and an immediate offset, and stores a byte to the calculated address, from a 32-bit register. For information about memory accesses, see Load/Store addressing modes.

313029282726252423222120191817161514131211109876543210
00111000000imm900RnRt
sizeVRopc

STURB <Wt>, [<Xn|SP>{, #<simm>}]

bits(64) offset = SignExtend(imm9, 64);

Assembler Symbols

<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.

<simm>

Is the optional signed immediate byte offset, in the range -256 to 255, defaulting to 0 and encoded in the "imm9" field.

Shared Decode

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

Operation

bits(64) address; bits(8) data; boolean privileged = PSTATE.EL != EL0; AccessDescriptor accdesc = CreateAccDescGPR(MemOp_STORE, FALSE, privileged, tagchecked); if n == 31 then CheckSPAlignment(); address = SP[]; else address = X[n, 64]; address = GenerateAddress(address, offset, accdesc); data = X[t, 8]; Mem[address, 1, accdesc] = data;

Operational information

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


Internal version only: aarchmrs v2023-12_rel, pseudocode v2023-12_rel, sve v2023-12_rel ; Build timestamp: 2023-12-15T16:46

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