Refactor dmprof: Split dmprof.py into modules.

tools/deep_memory_profiler/range_dict.py

-# Copyright (c) 2013 The Chromium Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-import os
-import sys
-
-BASE_PATH = os.path.dirname(os.path.abspath(__file__))
-BINTREES_PATH = os.path.join(
-    BASE_PATH, os.pardir, os.pardir, 'third_party', 'bintrees')
-sys.path.insert(0, BINTREES_PATH)
-
-from bintrees import FastRBTree  # pylint: disable=F0401
-
-
-class ExclusiveRangeDict(object):
-  """A class like dict whose key is a range [begin, end) of integers.
-
-  It has an attribute for each range of integers, for example:
-  [10, 20) => Attribute(0),
-  [20, 40) => Attribute(1),
-  [40, 50) => Attribute(2),
-  ...
-
-  An instance of this class is accessed only via iter_range(begin, end).
-  The instance is accessed as follows:
-
-  1) If the given range [begin, end) is not covered by the instance,
-  the range is newly created and iterated.
-
-  2) If the given range [begin, end) exactly covers ranges in the instance,
-  the ranges are iterated.
-  (See test_set() in tests/range_dict_tests.py.)
-
-  3) If the given range [begin, end) starts at and/or ends at a mid-point of
-  an existing range, the existing range is split by the given range, and
-  ranges in the given range are iterated.  For example, consider a case that
-  [25, 45) is given to an instance of [20, 30), [30, 40), [40, 50).  In this
-  case, [20, 30) is split into [20, 25) and [25, 30), and [40, 50) into
-  [40, 45) and [45, 50).  Then, [25, 30), [30, 40), [40, 45) are iterated.
-  (See test_split() in tests/range_dict_tests.py.)
-
-  4) If the given range [begin, end) includes non-existing ranges in an
-  instance, the gaps are filled with new ranges, and all ranges are iterated.
-  For example, consider a case that [25, 50) is given to an instance of
-  [30, 35) and [40, 45).  In this case, [25, 30), [35, 40) and [45, 50) are
-  created in the instance, and then [25, 30), [30, 35), [35, 40), [40, 45)
-  and [45, 50) are iterated.
-  (See test_fill() in tests/range_dict_tests.py.)
-  """
-  class RangeAttribute(object):
-    def __init__(self):
-      pass
-
-    def __str__(self):
-      return '<RangeAttribute>'
-
-    def __repr__(self):
-      return '<RangeAttribute>'
-
-    def copy(self):  # pylint: disable=R0201
-      return ExclusiveRangeDict.RangeAttribute()
-
-  def __init__(self, attr=RangeAttribute):
-    self._tree = FastRBTree()
-    self._attr = attr
-
-  def iter_range(self, begin=None, end=None):
-    if not begin:
-      begin = self._tree.min_key()
-    if not end:
-      end = self._tree.max_item()[1][0]
-
-    # Assume that self._tree has at least one element.
-    if self._tree.is_empty():
-      self._tree[begin] = (end, self._attr())
-
-    # Create a beginning range (border)
-    try:
-      bound_begin, bound_value = self._tree.floor_item(begin)
-      bound_end = bound_value[0]
-      if begin >= bound_end:
-        # Create a blank range.
-        try:
-          new_end, _ = self._tree.succ_item(bound_begin)
-        except KeyError:
-          new_end = end
-        self._tree[begin] = (min(end, new_end), self._attr())
-      elif bound_begin < begin and begin < bound_end:
-        # Split the existing range.
-        new_end = bound_value[0]
-        new_value = bound_value[1]
-        self._tree[bound_begin] = (begin, new_value.copy())
-        self._tree[begin] = (new_end, new_value.copy())
-      else:  # bound_begin == begin
-        # Do nothing (just saying it clearly since this part is confusing)
-        pass
-    except KeyError:  # begin is less than the smallest element.
-      # Create a blank range.
-      # Note that we can assume self._tree has at least one element.
-      self._tree[begin] = (min(end, self._tree.min_key()), self._attr())
-
-    # Create an ending range (border)
-    try:
-      bound_begin, bound_value = self._tree.floor_item(end)
-      bound_end = bound_value[0]
-      if end > bound_end:
-        # Create a blank range.
-        new_begin = bound_end
-        self._tree[new_begin] = (end, self._attr())
-      elif bound_begin < end and end < bound_end:
-        # Split the existing range.
-        new_end = bound_value[0]
-        new_value = bound_value[1]
-        self._tree[bound_begin] = (end, new_value.copy())
-        self._tree[end] = (new_end, new_value.copy())
-      else:  # bound_begin == begin
-        # Do nothing (just saying it clearly since this part is confusing)
-        pass
-    except KeyError:  # end is less than the smallest element.
-      # It must not happen.  A blank range [begin,end) has already been created
-      # even if [begin,end) is less than the smallest range.
-      # Do nothing (just saying it clearly since this part is confusing)
-      raise
-
-    missing_ranges = []
-
-    prev_end = None
-    for range_begin, range_value in self._tree.itemslice(begin, end):
-      range_end = range_value[0]
-      # Note that we can assume that we have a range beginning with |begin|
-      # and a range ending with |end| (they may be the same range).
-      if prev_end and prev_end != range_begin:
-        missing_ranges.append((prev_end, range_begin))
-      prev_end = range_end
-
-    for missing_begin, missing_end in missing_ranges:
-      self._tree[missing_begin] = (missing_end, self._attr())
-
-    for range_begin, range_value in self._tree.itemslice(begin, end):
-      yield range_begin, range_value[0], range_value[1]
-
-  def __str__(self):
-    return str(self._tree)