private void DecodeJTypeInstruction(Instruction i, string[] regAndImmed) { JTypeInstruction j = (JTypeInstruction)i; int[] regAndImmedValue = DetermineRegistersUsed(regAndImmed, j.instructionSubType); if (j.instructionSubType == InstructionSubType.li) { j.destinationRegister = regAndImmedValue[0]; j.immediateValue = regAndImmedValue[1]; } else { j.immediateValue = regAndImmedValue[0]; } }
// Determines which type of instruction to create based on if instruction is in a specific dictionary // and creates a new instruction of that type. Instructions are in the form of lw, sw, add, bal, etc. private Instruction CreateCorrectTypeOfInstruction(string instruction, int lineNum) { InstructionSubType subType; Instruction i = null; if (JInstructions.TryGetValue(instruction, out subType)) { JTypeInstruction j = new JTypeInstruction(); j.instructionSubType = subType; i = j; } else if (BInstructions.TryGetValue(instruction, out subType)) { BTypeInstruction b = new BTypeInstruction(); b.instructionSubType = subType; i = b; } else if (DInstructions.TryGetValue(instruction, out subType)) { DTypeInstruction d = new DTypeInstruction(); d.instructionSubType = subType; i = d; } else if (RInstructions.TryGetValue(instruction, out subType)) { RTypeInstruction r = new RTypeInstruction(); r.instructionSubType = subType; // Determines what the OpX bits should be based on the instruction given in the form add, sub, xor, etc. r.OpX = (RTypeInstruction.Opx)Enum.Parse(typeof(RTypeInstruction.Opx), instruction); i = r; } else { throw new InvalidInstructionException(String.Format("The instruction on line {0} is an invalid instruction.", lineNum)); } return(i); }