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/HashFunctions.h> 31 32 namespace JSC { 33 34 class NumericStrings { 35 public: 36 UString add(double d) 37 { 38 CacheEntry<double>& entry = lookup(d); 39 if (d == entry.key && !entry.value.isNull()) 40 return entry.value; 41 entry.key = d; 42 entry.value = UString::from(d); 43 return entry.value; 44 } 45 46 UString add(int i) 47 { 48 CacheEntry<int>& entry = lookup(i); 49 if (i == entry.key && !entry.value.isNull()) 50 return entry.value; 51 entry.key = i; 52 entry.value = UString::from(i); 53 return entry.value; 54 } 55 56 private: 57 static const size_t cacheSize = 64; 58 59 template<typename T> 60 struct CacheEntry { 61 T key; 62 UString value; 63 }; 64 65 CacheEntry<double>& lookup(double d) { return doubleCache[WTF::FloatHash<double>::hash(d) & (cacheSize - 1)]; } 66 CacheEntry<int>& lookup(int i) { return intCache[WTF::IntHash<int>::hash(i) & (cacheSize - 1)]; } 67 68 CacheEntry<double> doubleCache[cacheSize]; 69 CacheEntry<int> intCache[cacheSize]; 70 }; 71 72 } // namespace JSC 73 74 #endif // NumericStrings_h 75
