1/*
2 * Copyright (C) 2018 Yusuke Suzuki <[email protected]>.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
16 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR
17 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
18 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
19 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
20 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
21 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
23 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26#include "config.h"
27#include "ParseHash.h"
28
29#include "SourceCode.h"
30#include <wtf/SHA1.h>
31#include <wtf/SixCharacterHash.h>
32
33namespace JSC {
34
35ParseHash::ParseHash(const SourceCode& sourceCode)
36{
37 SHA1 sha1;
38 sha1.addBytes(sourceCode.toUTF8());
39 SHA1::Digest digest;
40 sha1.computeHash(digest);
41 unsigned hash = digest[0] | (digest[1] << 8) | (digest[2] << 16) | (digest[3] << 24);
42
43 if (hash == 0 || hash == 1)
44 hash += 0x2d5a93d0; // Ensures a non-zero hash, and gets us #Azero0 for CodeForCall and #Azero1 for CodeForConstruct.
45 static_assert(static_cast<unsigned>(CodeForCall) == 0, "");
46 static_assert(static_cast<unsigned>(CodeForConstruct) == 1, "");
47 unsigned hashForCall = hash ^ static_cast<unsigned>(CodeForCall);
48 unsigned hashForConstruct = hash ^ static_cast<unsigned>(CodeForConstruct);
49
50 m_hashForCall = CodeBlockHash(hashForCall);
51 m_hashForConstruct = CodeBlockHash(hashForConstruct);
52 ASSERT(hashForCall);
53 ASSERT(hashForConstruct);
54}
55
56} // namespace JSC
57
58