1/*
2 * Copyright (C) 2009 Apple Inc. All Rights Reserved.
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#ifndef NumericStrings_h
27#define NumericStrings_h
28
29#include <array>
30#include <wtf/HashFunctions.h>
31#include <wtf/text/WTFString.h>
32
33namespace JSC {
34
35class NumericStrings {
36public:
37 ALWAYS_INLINE String add(double d)
38 {
39 CacheEntry<double>& entry = lookup(d);
40 if (d == entry.key && !entry.value.isNull())
41 return entry.value;
42 entry.key = d;
43 entry.value = String::numberToStringECMAScript(d);
44 return entry.value;
45 }
46
47 ALWAYS_INLINE String add(int i)
48 {
49 if (static_cast<unsigned>(i) < cacheSize)
50 return lookupSmallString(static_cast<unsigned>(i));
51 CacheEntry<int>& entry = lookup(i);
52 if (i == entry.key && !entry.value.isNull())
53 return entry.value;
54 entry.key = i;
55 entry.value = String::number(i);
56 return entry.value;
57 }
58
59 ALWAYS_INLINE String add(unsigned i)
60 {
61 if (i < cacheSize)
62 return lookupSmallString(static_cast<unsigned>(i));
63 CacheEntry<unsigned>& entry = lookup(i);
64 if (i == entry.key && !entry.value.isNull())
65 return entry.value;
66 entry.key = i;
67 entry.value = String::number(i);
68 return entry.value;
69 }
70private:
71 static const size_t cacheSize = 64;
72
73 template<typename T>
74 struct CacheEntry {
75 T key;
76 String value;
77 };
78
79 CacheEntry<double>& lookup(double d) { return doubleCache[WTF::FloatHash<double>::hash(d) & (cacheSize - 1)]; }
80 CacheEntry<int>& lookup(int i) { return intCache[WTF::IntHash<int>::hash(i) & (cacheSize - 1)]; }
81 CacheEntry<unsigned>& lookup(unsigned i) { return unsignedCache[WTF::IntHash<unsigned>::hash(i) & (cacheSize - 1)]; }
82 ALWAYS_INLINE const String& lookupSmallString(unsigned i)
83 {
84 ASSERT(i < cacheSize);
85 if (smallIntCache[i].isNull())
86 smallIntCache[i] = String::number(i);
87 return smallIntCache[i];
88 }
89
90 std::array<CacheEntry<double>, cacheSize> doubleCache;
91 std::array<CacheEntry<int>, cacheSize> intCache;
92 std::array<CacheEntry<unsigned>, cacheSize> unsignedCache;
93 std::array<String, cacheSize> smallIntCache;
94};
95
96} // namespace JSC
97
98#endif // NumericStrings_h
99