rcl_asm.rb

require "pp"
require "json"

require_relative "common"

def parse(src)
  alines = []
  src.each_line do |line|
    words = line.sub(/#.*/, "").strip.split(/ +/)
    unless words.empty?
      alines << words
    end
  end
  alines
end

def create_label_addr_map(alines)
  map = {}

  alines.each_with_index do |aline, addr|
    head, *rest = aline

    case head
    when "label"
      name = rest[0]
      map[name] = addr
    end
  end

  map
end

def to_machine_code_operand(arg)
  case arg
  when /^\[(.+?):(.+?):(.+?)\]$/
    "mem:#{$1}:#{$2}:#{$3}"
  when /^\[(.+?):(.+?)\]$/
    "mem:#{$1}:#{$2}:0"
  when /^\[(reg_a)\]$/
    "mem:#{$1}:0:0"
  when /^-?\d+$/
    arg.to_i
  else
    arg
  end
end

src = File.read(ARGV[0])
alines = parse(src)

# key: ラベル名、 value: アドレス のマッピングを作る
label_addr_map = create_label_addr_map(alines)

alines.each do |aline|
  head, *rest = aline

  insn =
    if head == "label"
      ["_cmt"]
    else
      [head]
    end

  case head
  when "label"
    insn << "label:" + rest[0]
  when "jump", "jump_eq", "jump_g", "call"
    label_name = rest[0]

    if label_addr_map.key?(label_name)
      insn << label_addr_map[label_name] + 1
    else
      raise "label not found (#{label_name})"
    end
  else
    insn += rest.map {|arg| to_machine_code_operand(arg) }
  end

  puts JSON.generate(insn)
end