Class BenchmarkDriver < Object

# File benchmark/driver.rb, line 23
def self.benchmark(opt)
  driver = self.new(opt[:execs], opt[:dir], opt)
  begin
    driver.run
  ensure
    driver.show_results
  end
end

# File benchmark/driver.rb, line 56
def initialize execs, dir, opt = {}
  @execs = execs.map{|e|
    e.strip!
    next if e.empty?

    if /(.+)::(.+)/ =~ e
      # ex) ruby-a::/path/to/ruby-a
      label = $1.strip
      path = $2
      version = %x#{path} -v`.chomp
    else
      path = e
      version = label = %x#{path} -v`.chomp
    end
    [path, label, version]
  }.compact

  @dir = dir
  @repeat = opt[:repeat] || 1
  @repeat = 1 if @repeat < 1
  @pattern = opt[:pattern] || nil
  @exclude = opt[:exclude] || nil
  @verbose = opt[:quiet] ? false : (opt[:verbose] || false)
  @output = opt[:output] ? open(opt[:output], 'w') : nil
  @loop_wl1 = @loop_wl2 = nil
  @ruby_arg = opt[:ruby_arg] || nil
  @opt = opt

  # [[name, [[r-1-1, r-1-2, ...], [r-2-1, r-2-2, ...]]], ...]
  @results = []

  if @verbose
    @start_time = Time.now
    message @start_time
    @execs.each_with_index{|(path, label, version), i|
      message "target #{i}: " + (label == version ? "#{label}" : "#{label} (#{version})") + " at \"#{path}\""
    }
  end
end

# File benchmark/driver.rb, line 96
def adjusted_results name, results
  s = nil
  results.each_with_index{|e, i|
    r = e.min
    case name
    when /^vm1_/
      if @loop_wl1
        r -= @loop_wl1[i]
        r = 0 if r < 0
        s = '*'
      end
    when /^vm2_/
      if @loop_wl2
        r -= @loop_wl2[i]
        r = 0 if r < 0
        s = '*'
      end
    end
    yield r
  }
  s
end

# File benchmark/driver.rb, line 176
def files
  flag = {}
  @files = Dir.glob(File.join(@dir, 'bm*.rb')).map{|file|
    next if @pattern && /#{@pattern}/ !~ File.basename(file)
    next if @exclude && /#{@exclude}/ =~ File.basename(file)
    case file
    when /bm_(vm[12])_/, /bm_loop_(whileloop2?).rb/
      flag[$1] = true
    end
    file
  }.compact

  if flag['vm1'] && !flag['whileloop']
    @files << File.join(@dir, 'bm_loop_whileloop.rb')
  elsif flag['vm2'] && !flag['whileloop2']
    @files << File.join(@dir, 'bm_loop_whileloop2.rb')
  end

  @files.sort!
  progress_message "total: #{@files.size * @repeat} trial(s) (#{@repeat} trial(s) for #{@files.size} benchmark(s))\n"
  @files
end

# File benchmark/driver.rb, line 241
def measure executable, file
  cmd = "#{executable} #{@ruby_arg} #{file}"

  m = Benchmark.measure{
    system(cmd, out: File::NULL)
  }

  if $? != 0
    output "\`#{cmd}\' exited with abnormal status (#{$?})"
    0
  else
    m.real
  end
end

# File benchmark/driver.rb, line 212
def measure_file file
  name = File.basename(file, '.rb').sub(/^bm_/, '')
  prepare_file = File.join(File.dirname(file), "prepare_#{name}.rb")
  load prepare_file if FileTest.exist?(prepare_file)

  if @verbose
    output
    output '-----------------------------------------------------------'
    output name
    output
    output File.read(file)
    output
  end

  result = [name]
  result << @execs.map{|(e, v)|
    (0...@repeat).map{
      message_print "#{v}\t"
      progress_message '.'

      m = measure(e, file)
      message "#{m}"
      m
    }
  }
  @results << result
  result
end

# File benchmark/driver.rb, line 37
def message *args
  output(*args) if @verbose
end

# File benchmark/driver.rb, line 41
def message_print *args
  if @verbose
    print(*args)
    STDOUT.flush
    @output and @output.print(*args)
  end
end

# File benchmark/driver.rb, line 32
def output *args
  puts(*args)
  @output and @output.puts(*args)
end

# File benchmark/driver.rb, line 49
def progress_message *args
  unless STDOUT.tty?
    STDERR.print(*args)
    STDERR.flush
  end
end

# File benchmark/driver.rb, line 199
def run
  files.each_with_index{|file, i|
    @i = i
    r = measure_file(file)

    if /bm_loop_whileloop.rb/ =~ file
      @loop_wl1 = r[1].map{|e| e.min}
    elsif /bm_loop_whileloop2.rb/ =~ file
      @loop_wl2 = r[1].map{|e| e.min}
    end
  }
end

# File benchmark/driver.rb, line 119
def show_results
  output

  if @verbose
    message '-----------------------------------------------------------'
    message 'raw data:'
    message
    message PP.pp(@results, "", 79)
    message
    message "Elapsed time: #{Time.now - @start_time} (sec)"
  end

  output '-----------------------------------------------------------'
  output 'benchmark results:'

  if @verbose and @repeat > 1
    output "minimum results in each #{@repeat} measurements."
  end

  output "Execution time (sec)"
  output "name\t#{@execs.map{|(_, v)| v}.join("\t")}"
  @results.each{|v, result|
    rets = []
    s = adjusted_results(v, result){|r|
      rets << sprintf("%.3f", r)
    }
    output "#{v}#{s}\t#{rets.join("\t")}"
  }

  if @execs.size > 1
    output
    output "Speedup ratio: compare with the result of `#{@execs[0][1]}' (greater is better)"
    output "name\t#{@execs[1..-1].map{|(_, v)| v}.join("\t")}"
    @results.each{|v, result|
      rets = []
      first_value = nil
      s = adjusted_results(v, result){|r|
        if first_value
          if r == 0
            rets << "Error"
          else
            rets << sprintf("%.3f", first_value/r)
          end
        else
          first_value = r
        end
      }
      output "#{v}#{s}\t#{rets.join("\t")}"
    }
  end

  if @opt[:output]
    output
    output "Log file: #{@opt[:output]}"
  end
end