1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
|
#!/usr/bin/env python3
# Copyright 2023 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.
import base64
import sys
script_id_to_name = {}
script_id_to_start_positions = {}
def varint(n):
orig_mask = (1 << 7) - 1
mask = (1 << 7) - 1
res = []
shift = 0
while n > mask:
mask = mask << 7
shift += 7
while mask > orig_mask:
# This byte will start with 1
res.append((1 << 7) | ((n & mask) >> shift))
mask = mask >> 7
shift -= 7
assert (mask == orig_mask)
# This byte will start with 0
res.append(n & orig_mask)
return res
def encode_delta_varint_base64(start_positions):
bytes = []
prev_pos = 0
for p in start_positions:
bytes.extend(varint(p - prev_pos))
prev_pos = p
return base64.b64encode(bytearray(bytes)).decode()
def decode_varints(bytes):
ints = []
current = 0
for b in bytes:
if b & (1 << 7):
# Not the last byte
current = (current << 7) | (b & ((1 << 7) - 1))
else:
# The last byte
current = (current << 7) | b
ints.append(current)
current = 0
return ints
def decode_delta_varint_base64(comment):
bytes = base64.b64decode(comment)
deltas = decode_varints(bytes)
prev_pos = 0
positions = []
for d in deltas:
prev_pos += d
positions.append(prev_pos)
return positions
if len(sys.argv) < 2 or '--help' in sys.argv:
print('Usage: python3 generate-explicit-function-compile-hints.py v8.log')
exit(1)
with open(sys.argv[1], 'r') as log_file:
for line in log_file:
fields = line.strip().split(',')
if len(fields) >= 3:
if fields[0] == 'script-details':
script_id = int(fields[1])
script_name = fields[2]
script_id_to_name[script_id] = script_name
elif fields[0] == 'function' and fields[1] == 'parse-function':
script_id = int(fields[2])
start_position = int(fields[3])
if script_id in script_id_to_start_positions:
script_id_to_start_positions[script_id].add(start_position)
else:
script_id_to_start_positions[script_id] = {start_position}
for script_id, script_name in script_id_to_name.items():
if script_id in script_id_to_start_positions:
if not script_name.startswith('http') and not script_name.startswith(
'file'):
continue
start_positions = list(script_id_to_start_positions[script_id])
start_positions.sort()
print(script_name)
magic_comment = encode_delta_varint_base64(start_positions)
back = decode_delta_varint_base64(magic_comment)
if start_positions != back:
print('Decoding failed!')
exit(1)
print(f"//# experimentalChromiumCompileHintsData={magic_comment}\n")
|
