Pseudocode of SICXE

SICXEPass1.pseudo

BEGIN
	read first input line
	IF OPCODE = 'START' THEN
		BEGIN
			save #[OPERAND] as starting address
			initialize LOCCTR to starting address
			write line to intermediate file
			read next input line
		END {if START}
	ELSE
		initialize LOCCTR to 0
	WHILE OPCODE != 'END' DO
		BEGIN
			IF this is not a comment line THEN
				BEGIN
					IF there is a symbol in the LABEL field THEN
						BEGIN
							search SYMTAB for LABEL
							IF found THEN
								set error flag (duplicate symbol)
							ELSE
								insert (LABEL, LOCCTR) into SYMTAB
						END {if symbol}
					search OPTAB for OPCODE
					IF found THEN
						add 3 {instruction length} to LOCCTR
					ELSE IF OPCODE = 'WORD' THEN
						add 3 to LOCCTR
					ELSE IF OPCODE = 'RESW' THEN
						add 3 * #[OPERAND] to LOCCTR
					ELSE IF OPCODE = 'RESB' THEN
						add 3 #[OPERAND] to LOCCTR
					ELSE IF OPCODE = 'BYTE' THEN
						BEGIN
							find length of constant in bytes
							add length to LOCCTR
						END {if BYTE}
					ELSE
						set error flag (invalid operation code)
				END {if not a comment}
			write line to intermediate file
			read next input line
		END {while not END}
	write last line to intermediate file
	save (LOCCTR - starting address) as program length
END {Pass 1}

SICXEPass2.pseudo

BEGIN	
	read first input line {from intermediate file}
	IF OPCODE = 'START' THEN
		BEGIN
			write listing line
			read next input line
		END {if START}
	write Header record to object program
	initialize first Text record
	WHILE OPCODE != 'END' DO
		BEGIN
			IF this is not a comment line THEN
				BEGIN
					search OPTAB for OPCODE
					IF found THEN
						BEGIN
							IF there is a symbol in OPERAND field THEN
								BEGIN
								search SYMTAB for OPERAND
								IF found THEN
									store symbol value as operand address
								ELSE
									BEGIN
										store 0 as operand address
										set error flag (undefined symbol)
									END
								END {if symbol}
							ELSE
								store 0 as operand address
							assemble the object code instruction
						END {if opcode found}
					ELSE IF OPCODE = 'BYTE' or 'WORD' THEN
						convert constant to object code
					IF object code will not fit into the current Text record THEN
						BEGIN
							write Text record to object program
							initialize new Text record
						END
					add object code to Text record
				END {if not comment}
			write listing line
			read next input line
		END {while not END}
	write last Text record to object program
	write End record to object program
	write last listing line
END {Pass 2}