Pretty Printer for current Intermediate Representation (IR)

ir_dumper.rb

#!/usr/bin/env jruby
require 'jruby'

def get_ast(code)
  JRuby.parse(code)
end

def get_ir(ast_node)
  ir_manager = JRuby::runtime.ir_manager
  ir_manager.dry_run = true
  JRuby::IR.compiler_debug = true

  builder = 
    if JRuby::runtime.is1_9?
      org.jruby.ir.IRBuilder19
    else
      org.jruby.ir.IRBuilder
    end
  builder = builder.new(ir_manager)

  scope = builder.build_root(ast_node)
  ir_instrs(scope)
end

def ir_instrs(scope, indent="")
  instrs = scope.instrs.map do |instr|
    indent + instr.to_s
  end
  scope.lexical_scopes.each do |lex_scope|
    instrs += ir_instrs(lex_scope, indent + "\s" * 4)
  end
  instrs
end

def print_ir(code)
  root_node = get_ast(code)
  ir_instrs = get_ir(root_node)
  ir_instrs.each do |instr|
    puts instr
  end
end

example_code =
  if ARGV.length  == 1
    ARGV[0]
  else
    "def foo(x); return 41 + x; end"
  end
print_ir(example_code)