LDUR Load register (unscaled) This instruction calculates an address from a base register and an immediate offset, loads a 32-bit word or 64-bit doubleword from memory, zero-extends it, and writes it to a register. For information about addressing modes, see Load/Store addressing modes. If PSTATE.DIT is 1, the timing of this instruction is insensitive to the value of the data being loaded or stored. 1 x 1 1 1 0 0 0 0 1 0 0 0 0 LDUR <Wt>, [<Xn|SP>{, #<simm>}] 1 LDUR <Xt>, [<Xn|SP>{, #<simm>}] constant integer scale = UInt(size); constant bits(64) offset = SignExtend(imm9, 64); <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. <Xt> Is the 64-bit name of the general-purpose register to be transferred, encoded in the "Rt" field. constant integer n = UInt(Rn); constant integer t = UInt(Rt); constant integer datasize = 8 << scale; constant integer regsize = if datasize == 64 then 64 else 32; constant boolean nontemporal = FALSE; constant boolean tagchecked = n != 31; bits(64) address; constant boolean privileged = PSTATE.EL != EL0; constant AccessDescriptor accdesc = CreateAccDescGPR(MemOp_LOAD, nontemporal, privileged, tagchecked); if n == 31 then CheckSPAlignment(); address = SP[]; else address = X[n, 64]; address = AddressAdd(address, offset, accdesc); constant bits(datasize) data = Mem[address, datasize DIV 8, accdesc]; X[t, regsize] = ZeroExtend(data, regsize);