module ZJIT

# File zjit.rb, line 124
def dump_exit_locations(filename)
  unless trace_exit_locations_enabled?
    raise ArgumentError, "--zjit-trace-exits must be enabled to use dump_exit_locations."
  end

  File.open(filename, "wb") do |file|
    Marshal.dump(RubyVM::ZJIT.exit_locations, file)
    file.size
  end
end

# File zjit.rb, line 21
def enabled?
  Primitive.cexpr! 'RBOOL(rb_zjit_enabled_p)'
end

# File zjit.rb, line 34
def exit_locations
  return unless trace_exit_locations_enabled?

  results = Primitive.rb_zjit_get_exit_locations
  raw_samples = results[:raw].dup
  line_samples = results[:lines].dup
  frames = results[:frames].dup
  samples_count = 0

  # Loop through the instructions and set the frame hash with the data.
  # We use nonexistent.def for the file name, otherwise insns.def will be displayed
  # and that information isn't useful in this context.
  RubyVM::INSTRUCTION_NAMES.each_with_index do |name, frame_id|
    frame_hash = { samples: 0, total_samples: 0, edges: {}, name: name, file: "nonexistent.def", line: nil, lines: {} }
    results[:frames][frame_id] = frame_hash
    frames[frame_id] = frame_hash
  end

  # Loop through the raw_samples and build the hashes for StackProf.
  # The loop is based off an example in the StackProf documentation and therefore
  # this functionality can only work with that library.
  #
  # Raw Samples:
  # [ length, frame1, frame2, frameN, ..., instruction, count
  #
  # Line Samples
  # [ length, line_1, line_2, line_n, ..., dummy value, count
  i = 0
  while i < raw_samples.length
    stack_length = raw_samples[i]
    i += 1 # consume the stack length

    sample_count = raw_samples[i + stack_length]

    prev_frame_id = nil
    stack_length.times do |idx|
      idx += i
      frame_id = raw_samples[idx]

      if prev_frame_id
        prev_frame = frames[prev_frame_id]
        prev_frame[:edges][frame_id] ||= 0
        prev_frame[:edges][frame_id] += sample_count
      end

      frame_info = frames[frame_id]
      frame_info[:total_samples] += sample_count

      frame_info[:lines][line_samples[idx]] ||= [0, 0]
      frame_info[:lines][line_samples[idx]][0] += sample_count

      prev_frame_id = frame_id
    end

    i += stack_length # consume the stack

    top_frame_id = prev_frame_id
    top_frame_line = 1

    frames[top_frame_id][:samples] += sample_count
    frames[top_frame_id][:lines] ||= {}
    frames[top_frame_id][:lines][top_frame_line] ||= [0, 0]
    frames[top_frame_id][:lines][top_frame_line][1] += sample_count

    samples_count += sample_count
    i += 1
  end

  results[:samples] = samples_count
  # Set missed_samples and gc_samples to 0 as their values
  # don't matter to us in this context.
  results[:missed_samples] = 0
  results[:gc_samples] = 0
  results
end

# File zjit.rb, line 146
def reset_stats!
  Primitive.rb_zjit_reset_stats_bang
end

# File zjit.rb, line 141
def stats(target_key = nil)
  Primitive.rb_zjit_stats(target_key)
end

# File zjit.rb, line 136
def stats_enabled?
  Primitive.rb_zjit_stats_enabled_p
end

# File zjit.rb, line 151
def stats_string
  buf = +"***ZJIT: Printing ZJIT statistics on exit***\n"
  stats = self.stats

  # Show counters independent from exit_* or dynamic_send_*
  print_counters_with_prefix(prefix: 'not_inlined_cfuncs_', prompt: 'not inlined C methods', buf:, stats:, limit: 20)

  # Show fallback counters, ordered by the typical amount of fallbacks for the prefix at the time
  print_counters_with_prefix(prefix: 'unspecialized_def_type_', prompt: 'not optimized method types', buf:, stats:, limit: 20)
  print_counters_with_prefix(prefix: 'not_optimized_yarv_insn_', prompt: 'not optimized instructions', buf:, stats:, limit: 20)
  print_counters_with_prefix(prefix: 'send_fallback_', prompt: 'send fallback reasons', buf:, stats:, limit: 20)

  # Show exit counters, ordered by the typical amount of exits for the prefix at the time
  print_counters_with_prefix(prefix: 'unhandled_yarv_insn_', prompt: 'unhandled YARV insns', buf:, stats:, limit: 20)
  print_counters_with_prefix(prefix: 'compile_error_', prompt: 'compile error reasons', buf:, stats:, limit: 20)
  print_counters_with_prefix(prefix: 'exit_', prompt: 'side exit reasons', buf:, stats:, limit: 20)

  # Show no-prefix counters, having the most important stat `ratio_in_zjit` at the end
  print_counters([
    :send_count,
    :dynamic_send_count,
    :optimized_send_count,
    :iseq_optimized_send_count,
    :inline_cfunc_optimized_send_count,
    :non_variadic_cfunc_optimized_send_count,
    :variadic_cfunc_optimized_send_count,
  ], buf:, stats:, right_align: true, base: :send_count)
  print_counters([
    :dynamic_getivar_count,
    :dynamic_setivar_count,

    :compiled_iseq_count,
    :failed_iseq_count,

    :compile_time_ns,
    :profile_time_ns,
    :gc_time_ns,
    :invalidation_time_ns,

    :vm_write_pc_count,
    :vm_write_sp_count,
    :vm_write_locals_count,
    :vm_write_stack_count,
    :vm_write_to_parent_iseq_local_count,
    :vm_read_from_parent_iseq_local_count,

    :code_region_bytes,
    :side_exit_count,
    :total_insn_count,
    :vm_insn_count,
    :zjit_insn_count,
    :ratio_in_zjit,
  ], buf:, stats:)

  buf
end

# File zjit.rb, line 26
def trace_exit_locations_enabled?
  Primitive.rb_zjit_trace_exit_locations_enabled_p
end