#===- perf-helper.py - Clang Python Bindings -----------------*- python -*--===#
#
# The LLVM Compiler Infrastructure
#
# This file is distributed under the University of Illinois Open Source
# License. See LICENSE.TXT for details.
#
#===------------------------------------------------------------------------===#
from __future__ import print_function
import sys
import os
import subprocess
import argparse
import time
import bisect
import shlex
import tempfile
test_env = { 'PATH' : os.environ['PATH'] }
def findFilesWithExtension(path, extension):
filenames = []
for root, dirs, files in os.walk(path):
for filename in files:
if filename.endswith(extension):
filenames.append(os.path.join(root, filename))
return filenames
def clean(args):
if len(args) != 2:
print('Usage: %s clean <path> <extension>\n' % __file__ +
'\tRemoves all files with extension from <path>.')
return 1
for filename in findFilesWithExtension(args[0], args[1]):
os.remove(filename)
return 0
def merge(args):
if len(args) != 3:
print('Usage: %s clean <llvm-profdata> <output> <path>\n' % __file__ +
'\tMerges all profraw files from path into output.')
return 1
cmd = [args[0], 'merge', '-o', args[1]]
cmd.extend(findFilesWithExtension(args[2], "profraw"))
subprocess.check_call(cmd)
return 0
def dtrace(args):
parser = argparse.ArgumentParser(prog='perf-helper dtrace',
description='dtrace wrapper for order file generation')
parser.add_argument('--buffer-size', metavar='size', type=int, required=False,
default=1, help='dtrace buffer size in MB (default 1)')
parser.add_argument('--use-oneshot', required=False, action='store_true',
help='Use dtrace\'s oneshot probes')
parser.add_argument('--use-ustack', required=False, action='store_true',
help='Use dtrace\'s ustack to print function names')
parser.add_argument('--cc1', required=False, action='store_true',
help='Execute cc1 directly (don\'t profile the driver)')
parser.add_argument('cmd', nargs='*', help='')
# Use python's arg parser to handle all leading option arguments, but pass
# everything else through to dtrace
first_cmd = next(arg for arg in args if not arg.startswith("--"))
last_arg_idx = args.index(first_cmd)
opts = parser.parse_args(args[:last_arg_idx])
cmd = args[last_arg_idx:]
if opts.cc1:
cmd = get_cc1_command_for_args(cmd, test_env)
if opts.use_oneshot:
target = "oneshot$target:::entry"
else:
target = "pid$target:::entry"
predicate = '%s/probemod=="%s"/' % (target, os.path.basename(args[0]))
log_timestamp = 'printf("dtrace-TS: %d\\n", timestamp)'
if opts.use_ustack:
action = 'ustack(1);'
else:
action = 'printf("dtrace-Symbol: %s\\n", probefunc);'
dtrace_script = "%s { %s; %s }" % (predicate, log_timestamp, action)
dtrace_args = []
if not os.geteuid() == 0:
print(
'Script must be run as root, or you must add the following to your sudoers:'
+ '%%admin ALL=(ALL) NOPASSWD: /usr/sbin/dtrace')
dtrace_args.append("sudo")
dtrace_args.extend((
'dtrace', '-xevaltime=exec',
'-xbufsize=%dm' % (opts.buffer_size),
'-q', '-n', dtrace_script,
'-c', ' '.join(cmd)))
if sys.platform == "darwin":
dtrace_args.append('-xmangled')
start_time = time.time()
with open("%d.dtrace" % os.getpid(), "w") as f:
subprocess.check_call(dtrace_args, stdout=f, stderr=subprocess.PIPE)
elapsed = time.time() - start_time
print("... data collection took %.4fs" % elapsed)
return 0
def get_cc1_command_for_args(cmd, env):
# Find the cc1 command used by the compiler. To do this we execute the
# compiler with '-###' to figure out what it wants to do.
cmd = cmd + ['-###']
cc_output = subprocess.check_output(cmd, stderr=subprocess.STDOUT, env=env).strip()
cc_commands = []
for ln in cc_output.split('\n'):
# Filter out known garbage.
if (ln == 'Using built-in specs.' or
ln.startswith('Configured with:') or
ln.startswith('Target:') or
ln.startswith('Thread model:') or
ln.startswith('InstalledDir:') or
ln.startswith('LLVM Profile Note') or
' version ' in ln):
continue
cc_commands.append(ln)
if len(cc_commands) != 1:
print('Fatal error: unable to determine cc1 command: %r' % cc_output)
exit(1)
cc1_cmd = shlex.split(cc_commands[0])
if not cc1_cmd:
print('Fatal error: unable to determine cc1 command: %r' % cc_output)
exit(1)
return cc1_cmd
def cc1(args):
parser = argparse.ArgumentParser(prog='perf-helper cc1',
description='cc1 wrapper for order file generation')
parser.add_argument('cmd', nargs='*', help='')
# Use python's arg parser to handle all leading option arguments, but pass
# everything else through to dtrace
first_cmd = next(arg for arg in args if not arg.startswith("--"))
last_arg_idx = args.index(first_cmd)
opts = parser.parse_args(args[:last_arg_idx])
cmd = args[last_arg_idx:]
# clear the profile file env, so that we don't generate profdata
# when capturing the cc1 command
cc1_env = test_env
cc1_env["LLVM_PROFILE_FILE"] = os.devnull
cc1_cmd = get_cc1_command_for_args(cmd, cc1_env)
subprocess.check_call(cc1_cmd)
return 0
def parse_dtrace_symbol_file(path, all_symbols, all_symbols_set,
missing_symbols, opts):
def fix_mangling(symbol):
if sys.platform == "darwin":
if symbol[0] != '_' and symbol != 'start':
symbol = '_' + symbol
return symbol
def get_symbols_with_prefix(symbol):
start_index = bisect.bisect_left(all_symbols, symbol)
for s in all_symbols[start_index:]:
if not s.startswith(symbol):
break
yield s
# Extract the list of symbols from the given file, which is assumed to be
# the output of a dtrace run logging either probefunc or ustack(1) and
# nothing else. The dtrace -xdemangle option needs to be used.
#
# This is particular to OS X at the moment, because of the '_' handling.
with open(path) as f:
current_timestamp = None
for ln in f:
# Drop leading and trailing whitespace.
ln = ln.strip()
if not ln.startswith("dtrace-"):
continue
# If this is a timestamp specifier, extract it.
if ln.startswith("dtrace-TS: "):
_,data = ln.split(': ', 1)
if not data.isdigit():
print("warning: unrecognized timestamp line %r, ignoring" % ln,
file=sys.stderr)
continue
current_timestamp = int(data)
continue
elif ln.startswith("dtrace-Symbol: "):
_,ln = ln.split(': ', 1)
if not ln:
continue
# If there is a '`' in the line, assume it is a ustack(1) entry in
# the form of <modulename>`<modulefunc>, where <modulefunc> is never
# truncated (but does need the mangling patched).
if '`' in ln:
yield (current_timestamp, fix_mangling(ln.split('`',1)[1]))
continue
# Otherwise, assume this is a probefunc printout. DTrace on OS X
# seems to have a bug where it prints the mangled version of symbols
# which aren't C++ mangled. We just add a '_' to anything but start
# which doesn't already have a '_'.
symbol = fix_mangling(ln)
# If we don't know all the symbols, or the symbol is one of them,
# just return it.
if not all_symbols_set or symbol in all_symbols_set:
yield (current_timestamp, symbol)
continue
# Otherwise, we have a symbol name which isn't present in the
# binary. We assume it is truncated, and try to extend it.
# Get all the symbols with this prefix.
possible_symbols = list(get_symbols_with_prefix(symbol))
if not possible_symbols:
continue
# If we found too many possible symbols, ignore this as a prefix.
if len(possible_symbols) > 100:
print( "warning: ignoring symbol %r " % symbol +
"(no match and too many possible suffixes)", file=sys.stderr)
continue
# Report that we resolved a missing symbol.
if opts.show_missing_symbols and symbol not in missing_symbols:
print("warning: resolved missing symbol %r" % symbol, file=sys.stderr)
missing_symbols.add(symbol)
# Otherwise, treat all the possible matches as having occurred. This
# is an over-approximation, but it should be ok in practice.
for s in possible_symbols:
yield (current_timestamp, s)
def uniq(list):
seen = set()
for item in list:
if item not in seen:
yield item
seen.add(item)
def form_by_call_order(symbol_lists):
# Simply strategy, just return symbols in order of occurrence, even across
# multiple runs.
return uniq(s for symbols in symbol_lists for s in symbols)
def form_by_call_order_fair(symbol_lists):
# More complicated strategy that tries to respect the call order across all
# of the test cases, instead of giving a huge preference to the first test
# case.
# First, uniq all the lists.
uniq_lists = [list(uniq(symbols)) for symbols in symbol_lists]
# Compute the successors for each list.
succs = {}
for symbols in uniq_lists:
for a,b in zip(symbols[:-1], symbols[1:]):
succs[a] = items = succs.get(a, [])
if b not in items:
items.append(b)
# Emit all the symbols, but make sure to always emit all successors from any
# call list whenever we see a symbol.
#
# There isn't much science here, but this sometimes works better than the
# more naive strategy. Then again, sometimes it doesn't so more research is
# probably needed.
return uniq(s
for symbols in symbol_lists
for node in symbols
for s in ([node] + succs.get(node,[])))
def form_by_frequency(symbol_lists):
# Form the order file by just putting the most commonly occurring symbols
# first. This assumes the data files didn't use the oneshot dtrace method.
counts = {}
for symbols in symbol_lists:
for a in symbols:
counts[a] = counts.get(a,0) + 1
by_count = counts.items()
by_count.sort(key = lambda (_,n): -n)
return [s for s,n in by_count]
def form_by_random(symbol_lists):
# Randomize the symbols.
merged_symbols = uniq(s for symbols in symbol_lists
for s in symbols)
random.shuffle(merged_symbols)
return merged_symbols
def form_by_alphabetical(symbol_lists):
# Alphabetize the symbols.
merged_symbols = list(set(s for symbols in symbol_lists for s in symbols))
merged_symbols.sort()
return merged_symbols
methods = dict((name[len("form_by_"):],value)
for name,value in locals().items() if name.startswith("form_by_"))
def genOrderFile(args):
parser = argparse.ArgumentParser(
"%prog [options] <dtrace data file directories>]")
parser.add_argument('input', nargs='+', help='')
parser.add_argument("--binary", metavar="PATH", type=str, dest="binary_path",
help="Path to the binary being ordered (for getting all symbols)",
default=None)
parser.add_argument("--output", dest="output_path",
help="path to output order file to write", default=None, required=True,
metavar="PATH")
parser.add_argument("--show-missing-symbols", dest="show_missing_symbols",
help="show symbols which are 'fixed up' to a valid name (requires --binary)",
action="store_true", default=None)
parser.add_argument("--output-unordered-symbols",
dest="output_unordered_symbols_path",
help="write a list of the unordered symbols to PATH (requires --binary)",
default=None, metavar="PATH")
parser.add_argument("--method", dest="method",
help="order file generation method to use", choices=methods.keys(),
default='call_order')
opts = parser.parse_args(args)
# If the user gave us a binary, get all the symbols in the binary by
# snarfing 'nm' output.
if opts.binary_path is not None:
output = subprocess.check_output(['nm', '-P', opts.binary_path])
lines = output.split("\n")
all_symbols = [ln.split(' ',1)[0]
for ln in lines
if ln.strip()]
print("found %d symbols in binary" % len(all_symbols))
all_symbols.sort()
else:
all_symbols = []
all_symbols_set = set(all_symbols)
# Compute the list of input files.
input_files = []
for dirname in opts.input:
input_files.extend(findFilesWithExtension(dirname, "dtrace"))
# Load all of the input files.
print("loading from %d data files" % len(input_files))
missing_symbols = set()
timestamped_symbol_lists = [
list(parse_dtrace_symbol_file(path, all_symbols, all_symbols_set,
missing_symbols, opts))
for path in input_files]
# Reorder each symbol list.
symbol_lists = []
for timestamped_symbols_list in timestamped_symbol_lists:
timestamped_symbols_list.sort()
symbol_lists.append([symbol for _,symbol in timestamped_symbols_list])
# Execute the desire order file generation method.
method = methods.get(opts.method)
result = list(method(symbol_lists))
# Report to the user on what percentage of symbols are present in the order
# file.
num_ordered_symbols = len(result)
if all_symbols:
print("note: order file contains %d/%d symbols (%.2f%%)" % (
num_ordered_symbols, len(all_symbols),
100.*num_ordered_symbols/len(all_symbols)), file=sys.stderr)
if opts.output_unordered_symbols_path:
ordered_symbols_set = set(result)
with open(opts.output_unordered_symbols_path, 'w') as f:
f.write("\n".join(s for s in all_symbols if s not in ordered_symbols_set))
# Write the order file.
with open(opts.output_path, 'w') as f:
f.write("\n".join(result))
f.write("\n")
return 0
commands = {'clean' : clean,
'merge' : merge,
'dtrace' : dtrace,
'cc1' : cc1,
'gen-order-file' : genOrderFile}
def main():
f = commands[sys.argv[1]]
sys.exit(f(sys.argv[2:]))
if __name__ == '__main__':
main()