#!/usr/bin/env python
# Copyright 2019 the V8 project authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.
"""
python %prog trace-file
Parses output generated by v8 with flag --trace-regexp-bytecodes and generates
a list of the most common sequences.
from __future__ import print_function
import sys
import re
import collections
def parse(file, seqlen):
# example:
# pc = 00, sp = 0, curpos = 0, curchar = 0000000a ..., bc = PUSH_BT, 02, 00, 00, 00, e8, 00, 00, 00 .......
rx = re.compile(r'pc = (?P<pc>[0-9a-f]+), sp = (?P<sp>\d+), '
r'curpos = (?P<curpos>\d+), curchar = (?P<char_hex>[0-9a-f]+) '
r'(:?\.|\()(?P<char>\.|\w)(:?\.|\)), bc = (?P<bc>\w+), .*')
total = 0
bc_cnt = [None] * seqlen
for i in range(seqlen):
bc_cnt[i] = {}
last = [None] * seqlen
with open(file) as f:
l = f.readline()
while l:
l = l.strip()
if l.startswith("Start bytecode interpreter"):
last[i] = collections.deque(maxlen=i+1)
match = rx.search(l)
if match:
total += 1
bc = match.group('bc')
last[i].append(bc)
key = ' --> '.join(last[i])
bc_cnt[i][key] = bc_cnt[i].get(key,0) + 1
return bc_cnt, total
def print_most_common(d, seqlen, total):
sorted_d = sorted(d.items(), key=lambda kv: kv[1], reverse=True)
for (k,v) in sorted_d:
if v*100/total < 1.0:
return
print("{}: {} ({} %)".format(k,v,(v*100/total)))
def main(argv):
max_seq = 7
bc_cnt, total = parse(argv[1],max_seq)
for i in range(max_seq):
print()
print("Most common of length {}".format(i+1))
print_most_common(bc_cnt[i], i, total)
if __name__ == '__main__':
main(sys.argv)