blob: 379d5f40e390c837132fc6d8ba6e46794b3e54ef [file] [log] [blame]
#!/usr/bin/env python3
import argparse
import subprocess
from typing import *
import tempfile
import copy
import os
import shutil
import sys
import re
import configparser
from types import SimpleNamespace
from textwrap import dedent
# 0. Prepare two BOLT build versions: base and compare.
# 1. Create the config by invoking this script with required options.
# Save the config as `llvm-bolt-wrapper.ini` next to the script or
# in the testing directory.
# In the base BOLT build directory:
# 2. Rename `llvm-bolt` to `llvm-bolt.real`
# 3. Create a symlink from this script to `llvm-bolt`
# 4. Create `llvm-bolt-wrapper.ini` and fill it using the example below.
# This script will compare binaries produced by base and compare BOLT, and
# report elapsed processing time and max RSS.
# read options from config file llvm-bolt-wrapper.ini in script CWD
# [config]
# # mandatory
# base_bolt = /full/path/to/llvm-bolt.real
# cmp_bolt = /full/path/to/other/llvm-bolt
# # optional, default to False
# verbose
# keep_tmp
# no_minimize
# run_sequentially
# compare_output
# skip_binary_cmp
# # optional, defaults to timing.log in CWD
# timing_file = timing1.log
def read_cfg():
src_dir = os.path.dirname(os.path.abspath(__file__))
cfg = configparser.ConfigParser(allow_no_value = True)
cfgs ="llvm-bolt-wrapper.ini")
if not cfgs:
cfgs =, "llvm-bolt-wrapper.ini"))
assert cfgs, f"llvm-bolt-wrapper.ini is not found in {os.getcwd()}"
def get_cfg(key):
# if key is not present in config, assume False
if key not in cfg['config']:
return False
# if key is present, but has no value, assume True
if not cfg['config'][key]:
return True
# if key has associated value, interpret the value
return cfg['config'].getboolean(key)
d = {
# BOLT binary locations
'BASE_BOLT': cfg['config']['base_bolt'],
'CMP_BOLT': cfg['config']['cmp_bolt'],
# optional
'VERBOSE': get_cfg('verbose'),
'KEEP_TMP': get_cfg('keep_tmp'),
'NO_MINIMIZE': get_cfg('no_minimize'),
'RUN_SEQUENTIALLY': get_cfg('run_sequentially'),
'COMPARE_OUTPUT': get_cfg('compare_output'),
'SKIP_BINARY_CMP': get_cfg('skip_binary_cmp'),
'TIMING_FILE': cfg['config'].get('timing_file', 'timing.log'),
if d['VERBOSE']:
print(f"Using config {os.path.abspath(cfgs[0])}")
return SimpleNamespace(**d)
# perf2bolt mode
PERF2BOLT_MODE = ['-aggregate-only', '-ignore-build-id']
# boltdiff mode
BOLTDIFF_MODE = ['-diff-only', '-o', '/dev/null']
# options to suppress binary differences as much as possible
MINIMIZE_DIFFS = ['-bolt-info=0']
# bolt output options that need to be intercepted
'-o': 'BOLT output binary',
'-w': 'BOLT recorded profile',
# regex patterns to exclude the line from log comparison
'BOLT-INFO: BOLT version',
r'^Args: ',
r'BOLT-INFO:.*data.*output data',
'WARNING: reading perf data directly',
def run_cmd(cmd, out_f, cfg):
if cfg.VERBOSE:
print(' '.join(cmd))
return subprocess.Popen(cmd, stdout=out_f, stderr=subprocess.STDOUT)
def run_bolt(bolt_path, bolt_args, out_f, cfg):
p2b = os.path.basename(sys.argv[0]) == 'perf2bolt' # perf2bolt mode
bd = os.path.basename(sys.argv[0]) == 'llvm-boltdiff' # boltdiff mode
hm = sys.argv[1] == 'heatmap' # heatmap mode
cmd = ['/usr/bin/time', '-f', '%e %M', bolt_path] + bolt_args
if p2b:
# -ignore-build-id can occur at most once, hence remove it from cmd
if '-ignore-build-id' in cmd:
elif bd:
elif not cfg.NO_MINIMIZE and not hm:
return run_cmd(cmd, out_f, cfg)
def prepend_dash(args: Mapping[AnyStr, AnyStr]) -> Sequence[AnyStr]:
Accepts parsed arguments and returns flat list with dash prepended to
the option.
Example: Namespace(o='test.tmp') -> ['-o', 'test.tmp']
dashed = [('-'+key,value) for (key,value) in args.items()]
flattened = list(sum(dashed, ()))
return flattened
def replace_cmp_path(tmp: AnyStr, args: Mapping[AnyStr, AnyStr]) -> Sequence[AnyStr]:
Keeps file names, but replaces the path to a temp folder.
Example: Namespace(o='abc/test.tmp') -> Namespace(o='/tmp/tmpf9un/test.tmp')
Except preserve /dev/null.
replace_path = lambda x: os.path.join(tmp, os.path.basename(x)) if x != '/dev/null' else '/dev/null'
new_args = {key: replace_path(value) for key, value in args.items()}
return prepend_dash(new_args)
def preprocess_args(args: argparse.Namespace) -> Mapping[AnyStr, AnyStr]:
Drop options that weren't parsed (e.g. -w), convert to a dict
return {key: value for key, value in vars(args).items() if value}
def write_to(txt, filename, mode='w'):
with open(filename, mode) as f:
def wait(proc, fdesc):
return open(
def compare_logs(main, cmp, skip_begin=0, skip_end=0, str_input=True):
Compares logs but allows for certain lines to be excluded from comparison.
If str_input is True (default), the input it assumed to be a string,
which is split into lines. Otherwise the input is assumed to be a file.
Returns None on success, mismatch otherwise.
main_inp = main.splitlines() if str_input else main.readlines()
cmp_inp = cmp.splitlines() if str_input else cmp.readlines()
# rewind logs after consumption
if not str_input:
for lhs, rhs in list(zip(main_inp, cmp_inp))[skip_begin:-skip_end or None]:
if lhs != rhs:
# check skip patterns
for skip in SKIP_MATCH:
# both lines must contain the pattern
if, lhs) and, rhs):
# otherwise return mismatching lines
return (lhs, rhs)
return None
def fmt_cmp(cmp_tuple):
if not cmp_tuple:
return ''
return f'main:\n{cmp_tuple[0]}\ncmp:\n{cmp_tuple[1]}\n'
def compare_with(lhs, rhs, cmd, skip_begin=0, skip_end=0):
Runs cmd on both lhs and rhs and compares stdout.
Returns tuple (mismatch, lhs_stdout):
- if stdout matches between two files, mismatch is None,
- otherwise mismatch is a tuple of mismatching lines.
run = lambda binary: + [binary],
text=True, check=True,
run_lhs = run(lhs)
run_rhs = run(rhs)
cmp = compare_logs(run_lhs, run_rhs, skip_begin, skip_end)
return cmp, run_lhs
def parse_cmp_offset(cmp_out):
Extracts byte number from cmp output:
file1 file2 differ: byte X, line Y
return int('byte (\d+),', cmp_out).groups()[0])
def report_real_time(binary, main_err, cmp_err, cfg):
Extracts real time from stderr and appends it to TIMING FILE it as csv:
"output binary; base bolt; cmp bolt"
def get_real_from_stderr(logline):
return '; '.join(logline.split())
for line in main_err:
main = get_real_from_stderr(line)
for line in cmp_err:
cmp = get_real_from_stderr(line)
write_to(f"{binary}; {main}; {cmp}\n", cfg.TIMING_FILE, 'a')
# rewind logs after consumption
def clean_exit(tmp, out, exitcode, cfg):
# temp files are only cleaned on success
if not cfg.KEEP_TMP:
# report stdout and stderr from the main process
shutil.copyfileobj(out, sys.stdout)
def find_section(offset, readelf_hdr):
hdr = readelf_hdr.split('\n')
section = None
# extract sections table (parse objdump -hw output)
for line in hdr[5:-1]:
cols = line.strip().split()
# extract section offset
file_offset = int(cols[5], 16)
# section size
size = int(cols[2], 16)
if offset >= file_offset and offset <= file_offset + size:
if sys.stdout.isatty(): # terminal supports colors
section = cols[1]
return section
def main_config_generator():
parser = argparse.ArgumentParser()
parser.add_argument('base_bolt', help='Full path to base llvm-bolt binary')
parser.add_argument('cmp_bolt', help='Full path to cmp llvm-bolt binary')
parser.add_argument('--verbose', action='store_true',
help='Print subprocess invocation cmdline (default False)')
parser.add_argument('--keep_tmp', action='store_true',
help = 'Preserve tmp folder on a clean exit '
'(tmp directory is preserved on crash by default)')
parser.add_argument('--no_minimize', action='store_true',
help=f'Do not add `{MINIMIZE_DIFFS}` that is used '
'by default to reduce binary differences')
parser.add_argument('--run_sequentially', action='store_true',
help='Run both binaries sequentially (default '
'in parallel). Use for timing comparison')
parser.add_argument('--compare_output', action='store_true',
help = 'Compare bolt stdout/stderr (disabled by default)')
parser.add_argument('--skip_binary_cmp', action='store_true',
help = 'Disable output comparison')
parser.add_argument('--timing_file', help = 'Override path to timing log '
'file (default `timing.log` in CWD)')
args = parser.parse_args()
# mandatory
base_bolt = {args.base_bolt}
cmp_bolt = {args.cmp_bolt}'''))
del args.base_bolt
del args.cmp_bolt
d = vars(args)
if any(d.values()):
print("# optional")
for key, value in d.items():
if value:
def main():
cfg = read_cfg()
# intercept output arguments
parser = argparse.ArgumentParser(add_help=False)
for option, help in BOLT_OUTPUT_OPTS.items():
parser.add_argument(option, help=help)
args, unknownargs = parser.parse_known_args()
args = preprocess_args(args)
cmp_args = copy.deepcopy(args)
tmp = tempfile.mkdtemp()
cmp_args = replace_cmp_path(tmp, cmp_args)
# reconstruct output arguments: prepend dash
args = prepend_dash(args)
# run both BOLT binaries
main_f = open(os.path.join(tmp, 'main_bolt.stdout'), 'w')
cmp_f = open(os.path.join(tmp, 'cmp_bolt.stdout'), 'w')
main_bolt = run_bolt(cfg.BASE_BOLT, unknownargs + args, main_f, cfg)
main_out = wait(main_bolt, main_f)
cmp_bolt = run_bolt(cfg.CMP_BOLT, unknownargs + cmp_args, cmp_f, cfg)
cmp_bolt = run_bolt(cfg.CMP_BOLT, unknownargs + cmp_args, cmp_f, cfg)
main_out = wait(main_bolt, main_f)
cmp_out = wait(cmp_bolt, cmp_f)
# check exit code
if main_bolt.returncode != cmp_bolt.returncode:
exit("exitcode mismatch")
# compare logs, skip_end=1 skips the line with time
out = compare_logs(main_out, cmp_out, skip_end=1, str_input=False) if cfg.COMPARE_OUTPUT else None
if out:
write_to(fmt_cmp(out), os.path.join(tmp, 'summary.txt'))
exit("logs mismatch")
if os.path.basename(sys.argv[0]) == 'llvm-boltdiff': # boltdiff mode
# no output binary to compare, so just exit
clean_exit(tmp, main_out, main_bolt.returncode, cfg)
# compare binaries (using cmp)
main_binary = args[args.index('-o')+1]
cmp_binary = cmp_args[cmp_args.index('-o')+1]
if main_binary == '/dev/null':
assert cmp_binary == '/dev/null'
# report binary timing as csv: output binary; base bolt real; cmp bolt real
report_real_time(main_binary, main_out, cmp_out, cfg)
# check if files exist
main_exists = os.path.exists(main_binary)
cmp_exists = os.path.exists(cmp_binary)
if main_exists and cmp_exists:
# proceed to comparison
elif not main_exists and not cmp_exists:
# both don't exist, assume it's intended, skip comparison
clean_exit(tmp, main_out, main_bolt.returncode, cfg)
elif main_exists:
assert not cmp_exists
exit(f"{cmp_binary} doesn't exist")
assert not main_exists
exit(f"{main_binary} doesn't exist")
if not cfg.SKIP_BINARY_CMP:
cmp_proc =['cmp', '-b', main_binary, cmp_binary],
capture_output=True, text=True)
if cmp_proc.returncode:
# check if output is an ELF file (magic bytes)
with open(main_binary, 'rb') as f:
magic =
if magic != b'\x7fELF':
exit("output mismatch")
# check if ELF headers match
mismatch, _ = compare_with(main_binary, cmp_binary, 'readelf -We')
if mismatch:
write_to(fmt_cmp(mismatch), os.path.join(tmp, 'headers.txt'))
exit("headers mismatch")
# if headers match, compare sections (skip line with filename)
mismatch, hdr = compare_with(main_binary, cmp_binary, 'objdump -hw',
assert not mismatch
# check which section has the first mismatch
mismatch_offset = parse_cmp_offset(cmp_proc.stdout)
section = find_section(mismatch_offset, hdr)
exit(f"binary mismatch @{hex(mismatch_offset)} ({section})")
clean_exit(tmp, main_out, main_bolt.returncode, cfg)
if __name__ == "__main__":
# config generator mode if the script is launched as is
if os.path.basename(__file__) == "":
# llvm-bolt interceptor mode otherwise