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-rw-r--r--Source/JavaScriptCore/runtime/NumericStrings.h98
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diff --git a/Source/JavaScriptCore/runtime/NumericStrings.h b/Source/JavaScriptCore/runtime/NumericStrings.h
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+/*
+ * Copyright (C) 2009 Apple Inc. All Rights Reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
+ * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef NumericStrings_h
+#define NumericStrings_h
+
+#include "UString.h"
+#include <wtf/FixedArray.h>
+#include <wtf/HashFunctions.h>
+
+namespace JSC {
+
+ class NumericStrings {
+ public:
+ UString add(double d)
+ {
+ CacheEntry<double>& entry = lookup(d);
+ if (d == entry.key && !entry.value.isNull())
+ return entry.value;
+ entry.key = d;
+ entry.value = UString::number(d);
+ return entry.value;
+ }
+
+ UString add(int i)
+ {
+ if (static_cast<unsigned>(i) < cacheSize)
+ return lookupSmallString(static_cast<unsigned>(i));
+ CacheEntry<int>& entry = lookup(i);
+ if (i == entry.key && !entry.value.isNull())
+ return entry.value;
+ entry.key = i;
+ entry.value = UString::number(i);
+ return entry.value;
+ }
+
+ UString add(unsigned i)
+ {
+ if (i < cacheSize)
+ return lookupSmallString(static_cast<unsigned>(i));
+ CacheEntry<unsigned>& entry = lookup(i);
+ if (i == entry.key && !entry.value.isNull())
+ return entry.value;
+ entry.key = i;
+ entry.value = UString::number(i);
+ return entry.value;
+ }
+ private:
+ static const size_t cacheSize = 64;
+
+ template<typename T>
+ struct CacheEntry {
+ T key;
+ UString value;
+ };
+
+ CacheEntry<double>& lookup(double d) { return doubleCache[WTF::FloatHash<double>::hash(d) & (cacheSize - 1)]; }
+ CacheEntry<int>& lookup(int i) { return intCache[WTF::IntHash<int>::hash(i) & (cacheSize - 1)]; }
+ CacheEntry<unsigned>& lookup(unsigned i) { return unsignedCache[WTF::IntHash<unsigned>::hash(i) & (cacheSize - 1)]; }
+ const UString& lookupSmallString(unsigned i)
+ {
+ ASSERT(i < cacheSize);
+ if (smallIntCache[i].isNull())
+ smallIntCache[i] = UString::number(i);
+ return smallIntCache[i];
+ }
+
+ FixedArray<CacheEntry<double>, cacheSize> doubleCache;
+ FixedArray<CacheEntry<int>, cacheSize> intCache;
+ FixedArray<CacheEntry<unsigned>, cacheSize> unsignedCache;
+ FixedArray<UString, cacheSize> smallIntCache;
+ };
+
+} // namespace JSC
+
+#endif // NumericStrings_h