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STTRB

Store register byte (unprivileged)

This instruction stores a byte from a 32-bit register to memory. The address that is used for the store is calculated from a base register and an immediate offset.

Explicit Memory effects produced by the instruction behave as if the instruction was executed at EL0 if the Effective value of PSTATE.UAO is 0 and either:

• The instruction is executed at EL1.
• The instruction is executed at EL2 when the Effective value of HCR_EL2().{E2H, TGE} is '11'.

Otherwise, the Explicit Memory effects operate with the restrictions determined by the Exception level at which the instruction is executed.

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

Decode for this encoding

let offset : bits(64) = SignExtend{}(imm9);