mkmcode

#!/usr/bin/ruby
#-------------------------------------------------------------------------
#  MicroCode source generator for "HD63701 Compatible Processor Core"
#-------------------------------------------------------------------------
def deepcopy(obj)
	Marshal.load(Marshal.dump(obj))
end

def line_split(text)

	if (text == nil) then return nil end

	t = text.split(nil)
	s = Array.new
	for n in 0..(t.length-1) do
		cs = t[n].split(//)
		if (cs[0]=="\"") then
			s[n] = text.slice(/\".+\"/)
			break
		else
			s[n] = t[n]
		end
	end
	return s
end

def parser(inname)

	$parsed = Array.new

	nowop   = -1;
	rawout  = 0;

	open(inname){|infile|
		while !infile.eof? do
			rtext = infile.gets
			text  = rtext.strip
			chrs  = text.split(//)

			if (chrs[0] == "%") then
				rawout = rawout^1
				next
			end
			if (rawout != 0) then
				print rtext
				next
			end

			if (chrs[0] == "#") then next end

			words = line_split(text)
			if (chrs[0] == "$") then
				nowop = (chrs[1]+chrs[2]).hex
				$parsed[nowop] = Array.new
				$parsed[nowop][0] = words
			else
				if (words.length > 0) then $parsed[nowop] << words end
			end
		end
	}
end

def get_maxstage

	n = 0;
	$parsed.each{|opc|
		if (opc == nil) then next end
		if (n < opc.length) then n = opc.length end
	}
	return n-1
end


def out_stage_header(stage)

	printf("\nfunction `mcwidth MCODE_S%d;\n", stage-1);
	printf("input [7:0] opc;\n");
	printf("begin\n")
	printf("\tcase (opc)\n");
end

def out_stage_mc_sub(stage,opcode,nemonic,mcode)

	if (mcode == nil) then return 0 end

	printf("\t\t8'h%s: MCODE_S%d = ", opcode[1,2], stage-1)
	if ((mcode[0].split(//))[0] == "\"") then
		raw = (mcode[0])[1..((mcode[0]).length-2)]
		if ( raw.length > 16 ) then
			printf("%s;\t\t// %s\n", raw, nemonic);
		else
			printf("%s;\t\t\t\t\t\t\t\t\t\t\t\t\t// %s\n", raw, nemonic);
		end
	else
		mrs = mcode[1].split(//)
		printf("{\`mc%s,\`mcr%s,\`mcr%s,\`mcr%s,\`mcp%s,\`am%s,\`pc%s};\t\t// %s\n",
			mcode[0], mrs[0], mrs[1], mrs[2], mcode[2], mcode[3], mcode[4], nemonic)
	end
	return 1
end

def out_stage_mc(stage,parsed_op)

	if (parsed_op == nil) then return 0 end

	if (stage == 1 && parsed_op[0].length > 2) then
		mcode = deepcopy( parsed_op[0] )
		2.times{ mcode.shift }
	else
		mcode = parsed_op[stage]
	end

	return out_stage_mc_sub(stage,parsed_op[0][0],parsed_op[0][1],mcode)
end

def out_stage_footer(stage)

	printf("\t default: MCODE_S%d = `MC_%s;\n", stage-1, (stage>1) ? "HALT" : "TRAP" )
	printf("\tendcase\n")
	printf("end\n")
	printf("endfunction\n\n");
end

def generate_stage_mcode(stage)

	separator = "//-----------------------------------------------------------------------------------------\n"
	flg = 1

	out_stage_header(stage)
	for op in 0x00..0xFF do
		if (op % 16 == 0 && flg != 0) then
			printf(separator)
			flg = 0
		end
		flg |= out_stage_mc(stage,$parsed[op])
	end
	if (flg != 0) then printf(separator) end
	out_stage_footer(stage)
end

def generate_mcode
	stages = get_maxstage
	for stage in 1..stages do generate_stage_mcode(stage) end
	printf("\n")
end


def doit
	parser("mcode.txt")
	generate_mcode
end

doit