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 "UString.h" 30 #include <wtf/FixedArray.h> 31 #include <wtf/HashFunctions.h> 32 33 namespace JSC { 34 35 class NumericStrings { 36 public: 37 UString 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 = UString::number(d); 44 return entry.value; 45 } 46 47 UString 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 = UString::number(i); 56 return entry.value; 57 } 58 59 UString 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 = UString::number(i); 68 return entry.value; 69 } 70 private: 71 static const size_t cacheSize = 64; 72 73 template<typename T> 74 struct CacheEntry { 75 T key; 76 UString 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 const UString& lookupSmallString(unsigned i) 83 { 84 ASSERT(i < cacheSize); 85 if (smallIntCache[i].isNull()) 86 smallIntCache[i] = UString::number(i); 87 return smallIntCache[i]; 88 } 89 90 FixedArray<CacheEntry<double>, cacheSize> doubleCache; 91 FixedArray<CacheEntry<int>, cacheSize> intCache; 92 FixedArray<CacheEntry<unsigned>, cacheSize> unsignedCache; 93 FixedArray<UString, cacheSize> smallIntCache; 94 }; 95 96 } // namespace JSC 97 98 #endif // NumericStrings_h 99
