ComputerOrganizationAssignment Custom Instructions Opcode Instruction Semantics Syntax Type 10100 Reverse Subraction Performs reg1 = reg3 - reg2. In case reg2 > reg3, 0 is written to reg1 and overflow flag is set. rsb reg1 reg2 reg3 A 10110 Decrement by Imm Performs reg1 = reg1 - Imm dec reg1 $Imm B 10011 Increment by Imm Performs reg1 = reg1 + Imm inc reg1 $Imm B 10111 Compares the register with Imm Compares reg1 and Imm, sets up the FLAGS register. cmn reg1 $Imm B 10101 Swap the data in register and memory Performs reg1,mem_addr = mem_addr, reg1 swp reg1 mem_addr D
