Python code coverage for Tools/scripts/analyze_dxp.py

#	count	content
1	n/a	"""
2	n/a	Some helper functions to analyze the output of sys.getdxp() (which is
3	n/a	only available if Python was built with -DDYNAMIC_EXECUTION_PROFILE).
4	n/a	These will tell you which opcodes have been executed most frequently
5	n/a	in the current process, and, if Python was also built with -DDXPAIRS,
6	n/a	will tell you which instruction _pairs_ were executed most frequently,
7	n/a	which may help in choosing new instructions.
8	n/a
9	n/a	If Python was built without -DDYNAMIC_EXECUTION_PROFILE, importing
10	n/a	this module will raise a RuntimeError.
11	n/a
12	n/a	If you're running a script you want to profile, a simple way to get
13	n/a	the common pairs is:
14	n/a
15	n/a	$ PYTHONPATH=$PYTHONPATH:<python_srcdir>/Tools/scripts \
16	n/a	./python -i -O the_script.py --args
17	n/a	...
18	n/a	> from analyze_dxp import *
19	n/a	> s = render_common_pairs()
20	n/a	> open('/tmp/some_file', 'w').write(s)
21	n/a	"""
22	n/a
23	n/a	import copy
24	n/a	import opcode
25	n/a	import operator
26	n/a	import sys
27	n/a	import threading
28	n/a
29	n/a	if not hasattr(sys, "getdxp"):
30	n/a	raise RuntimeError("Can't import analyze_dxp: Python built without"
31	n/a	" -DDYNAMIC_EXECUTION_PROFILE.")
32	n/a
33	n/a
34	n/a	_profile_lock = threading.RLock()
35	n/a	_cumulative_profile = sys.getdxp()
36	n/a
37	n/a	# If Python was built with -DDXPAIRS, sys.getdxp() returns a list of
38	n/a	# lists of ints. Otherwise it returns just a list of ints.
39	n/a	def has_pairs(profile):
40	n/a	"""Returns True if the Python that produced the argument profile
41	n/a	was built with -DDXPAIRS."""
42	n/a
43	n/a	return len(profile) > 0 and isinstance(profile[0], list)
44	n/a
45	n/a
46	n/a	def reset_profile():
47	n/a	"""Forgets any execution profile that has been gathered so far."""
48	n/a	with _profile_lock:
49	n/a	sys.getdxp() # Resets the internal profile
50	n/a	global _cumulative_profile
51	n/a	_cumulative_profile = sys.getdxp() # 0s out our copy.
52	n/a
53	n/a
54	n/a	def merge_profile():
55	n/a	"""Reads sys.getdxp() and merges it into this module's cached copy.
56	n/a
57	n/a	We need this because sys.getdxp() 0s itself every time it's called."""
58	n/a
59	n/a	with _profile_lock:
60	n/a	new_profile = sys.getdxp()
61	n/a	if has_pairs(new_profile):
62	n/a	for first_inst in range(len(_cumulative_profile)):
63	n/a	for second_inst in range(len(_cumulative_profile[first_inst])):
64	n/a	_cumulative_profile[first_inst][second_inst] += (
65	n/a	new_profile[first_inst][second_inst])
66	n/a	else:
67	n/a	for inst in range(len(_cumulative_profile)):
68	n/a	_cumulative_profile[inst] += new_profile[inst]
69	n/a
70	n/a
71	n/a	def snapshot_profile():
72	n/a	"""Returns the cumulative execution profile until this call."""
73	n/a	with _profile_lock:
74	n/a	merge_profile()
75	n/a	return copy.deepcopy(_cumulative_profile)
76	n/a
77	n/a
78	n/a	def common_instructions(profile):
79	n/a	"""Returns the most common opcodes in order of descending frequency.
80	n/a
81	n/a	The result is a list of tuples of the form
82	n/a	(opcode, opname, # of occurrences)
83	n/a
84	n/a	"""
85	n/a	if has_pairs(profile) and profile:
86	n/a	inst_list = profile[-1]
87	n/a	else:
88	n/a	inst_list = profile
89	n/a	result = [(op, opcode.opname[op], count)
90	n/a	for op, count in enumerate(inst_list)
91	n/a	if count > 0]
92	n/a	result.sort(key=operator.itemgetter(2), reverse=True)
93	n/a	return result
94	n/a
95	n/a
96	n/a	def common_pairs(profile):
97	n/a	"""Returns the most common opcode pairs in order of descending frequency.
98	n/a
99	n/a	The result is a list of tuples of the form
100	n/a	((1st opcode, 2nd opcode),
101	n/a	(1st opname, 2nd opname),
102	n/a	# of occurrences of the pair)
103	n/a
104	n/a	"""
105	n/a	if not has_pairs(profile):
106	n/a	return []
107	n/a	result = [((op1, op2), (opcode.opname[op1], opcode.opname[op2]), count)
108	n/a	# Drop the row of single-op profiles with [:-1]
109	n/a	for op1, op1profile in enumerate(profile[:-1])
110	n/a	for op2, count in enumerate(op1profile)
111	n/a	if count > 0]
112	n/a	result.sort(key=operator.itemgetter(2), reverse=True)
113	n/a	return result
114	n/a
115	n/a
116	n/a	def render_common_pairs(profile=None):
117	n/a	"""Renders the most common opcode pairs to a string in order of
118	n/a	descending frequency.
119	n/a
120	n/a	The result is a series of lines of the form:
121	n/a	# of occurrences: ('1st opname', '2nd opname')
122	n/a
123	n/a	"""
124	n/a	if profile is None:
125	n/a	profile = snapshot_profile()
126	n/a	def seq():
127	n/a	for _, ops, count in common_pairs(profile):
128	n/a	yield "%s: %s\n" % (count, ops)
129	n/a	return ''.join(seq())