Merge WebKit at r75315: Initial merge by git.

Change-Id: I570314b346ce101c935ed22a626b48c2af266b84

1 files changed, 312 insertions, 0 deletions

diff --git a/Source/JavaScriptCore/runtime/Identifier.cpp b/Source/JavaScriptCore/runtime/Identifier.cpp
new file mode 100644
index 0000000..28cfd0a
--- /dev/null
+++ b/Source/JavaScriptCore/runtime/Identifier.cpp
@@ -0,0 +1,312 @@
+/*
+ *  Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008 Apple Inc. All rights reserved.
+ *
+ *  This library is free software; you can redistribute it and/or
+ *  modify it under the terms of the GNU Library General Public
+ *  License as published by the Free Software Foundation; either
+ *  version 2 of the License, or (at your option) any later version.
+ *
+ *  This library is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ *  Library General Public License for more details.
+ *
+ *  You should have received a copy of the GNU Library General Public License
+ *  along with this library; see the file COPYING.LIB.  If not, write to
+ *  the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+ *  Boston, MA 02110-1301, USA.
+ *
+ */
+
+#include "config.h"
+#include "Identifier.h"
+
+#include "CallFrame.h"
+#include "NumericStrings.h"
+#include <new> // for placement new
+#include <string.h> // for strlen
+#include <wtf/Assertions.h>
+#include <wtf/FastMalloc.h>
+#include <wtf/HashSet.h>
+#include <wtf/WTFThreadData.h>
+#include <wtf/text/StringHash.h>
+
+using WTF::ThreadSpecific;
+
+namespace JSC {
+
+IdentifierTable::~IdentifierTable()
+{
+    HashSet<StringImpl*>::iterator end = m_table.end();
+    for (HashSet<StringImpl*>::iterator iter = m_table.begin(); iter != end; ++iter)
+        (*iter)->setIsIdentifier(false);
+}
+std::pair<HashSet<StringImpl*>::iterator, bool> IdentifierTable::add(StringImpl* value)
+{
+    std::pair<HashSet<StringImpl*>::iterator, bool> result = m_table.add(value);
+    (*result.first)->setIsIdentifier(true);
+    return result;
+}
+template<typename U, typename V>
+std::pair<HashSet<StringImpl*>::iterator, bool> IdentifierTable::add(U value)
+{
+    std::pair<HashSet<StringImpl*>::iterator, bool> result = m_table.add<U, V>(value);
+    (*result.first)->setIsIdentifier(true);
+    return result;
+}
+
+IdentifierTable* createIdentifierTable()
+{
+    return new IdentifierTable;
+}
+
+void deleteIdentifierTable(IdentifierTable* table)
+{
+    delete table;
+}
+
+bool Identifier::equal(const StringImpl* r, const char* s)
+{
+    int length = r->length();
+    const UChar* d = r->characters();
+    for (int i = 0; i != length; ++i)
+        if (d[i] != (unsigned char)s[i])
+            return false;
+    return s[length] == 0;
+}
+
+bool Identifier::equal(const StringImpl* r, const UChar* s, unsigned length)
+{
+    if (r->length() != length)
+        return false;
+    const UChar* d = r->characters();
+    for (unsigned i = 0; i != length; ++i)
+        if (d[i] != s[i])
+            return false;
+    return true;
+}
+
+struct IdentifierCStringTranslator {
+    static unsigned hash(const char* c)
+    {
+        return WTF::StringHasher::createHash<char>(c);
+    }
+
+    static bool equal(StringImpl* r, const char* s)
+    {
+        return Identifier::equal(r, s);
+    }
+
+    static void translate(StringImpl*& location, const char* c, unsigned hash)
+    {
+        size_t length = strlen(c);
+        UChar* d;
+        StringImpl* r = StringImpl::createUninitialized(length, d).leakRef();
+        for (size_t i = 0; i != length; i++)
+            d[i] = static_cast<unsigned char>(c[i]); // use unsigned char to zero-extend instead of sign-extend
+        r->setHash(hash);
+        location = r;
+    }
+};
+
+PassRefPtr<StringImpl> Identifier::add(JSGlobalData* globalData, const char* c)
+{
+    if (!c)
+        return 0;
+    if (!c[0])
+        return StringImpl::empty();
+    if (!c[1])
+        return add(globalData, globalData->smallStrings.singleCharacterStringRep(static_cast<unsigned char>(c[0])));
+
+    IdentifierTable& identifierTable = *globalData->identifierTable;
+    LiteralIdentifierTable& literalIdentifierTable = identifierTable.literalTable();
+
+    const LiteralIdentifierTable::iterator& iter = literalIdentifierTable.find(c);
+    if (iter != literalIdentifierTable.end())
+        return iter->second;
+
+    pair<HashSet<StringImpl*>::iterator, bool> addResult = identifierTable.add<const char*, IdentifierCStringTranslator>(c);
+
+    // If the string is newly-translated, then we need to adopt it.
+    // The boolean in the pair tells us if that is so.
+    RefPtr<StringImpl> addedString = addResult.second ? adoptRef(*addResult.first) : *addResult.first;
+
+    literalIdentifierTable.add(c, addedString.get());
+
+    return addedString.release();
+}
+
+PassRefPtr<StringImpl> Identifier::add(ExecState* exec, const char* c)
+{
+    return add(&exec->globalData(), c);
+}
+
+struct UCharBuffer {
+    const UChar* s;
+    unsigned int length;
+};
+
+struct IdentifierUCharBufferTranslator {
+    static unsigned hash(const UCharBuffer& buf)
+    {
+        return WTF::StringHasher::createHash<UChar>(buf.s, buf.length);
+    }
+
+    static bool equal(StringImpl* str, const UCharBuffer& buf)
+    {
+        return Identifier::equal(str, buf.s, buf.length);
+    }
+
+    static void translate(StringImpl*& location, const UCharBuffer& buf, unsigned hash)
+    {
+        UChar* d;
+        StringImpl* r = StringImpl::createUninitialized(buf.length, d).leakRef();
+        for (unsigned i = 0; i != buf.length; i++)
+            d[i] = buf.s[i];
+        r->setHash(hash);
+        location = r; 
+    }
+};
+
+uint32_t Identifier::toUInt32(const UString& string, bool& ok)
+{
+    ok = false;
+
+    unsigned length = string.length();
+    const UChar* characters = string.characters();
+
+    // An empty string is not a number.
+    if (!length)
+        return 0;
+
+    // Get the first character, turning it into a digit.
+    uint32_t value = characters[0] - '0';
+    if (value > 9)
+        return 0;
+
+    // Check for leading zeros. If the first characher is 0, then the
+    // length of the string must be one - e.g. "042" is not equal to "42".
+    if (!value && length > 1)
+        return 0;
+
+    while (--length) {
+        // Multiply value by 10, checking for overflow out of 32 bits.
+        if (value > 0xFFFFFFFFU / 10)
+            return 0;
+        value *= 10;
+
+        // Get the next character, turning it into a digit.
+        uint32_t newValue = *(++characters) - '0';
+        if (newValue > 9)
+            return 0;
+
+        // Add in the old value, checking for overflow out of 32 bits.
+        newValue += value;
+        if (newValue < value)
+            return 0;
+        value = newValue;
+    }
+
+    ok = true;
+    return value;
+}
+
+PassRefPtr<StringImpl> Identifier::add(JSGlobalData* globalData, const UChar* s, int length)
+{
+    if (length == 1) {
+        UChar c = s[0];
+        if (c <= 0xFF)
+            return add(globalData, globalData->smallStrings.singleCharacterStringRep(c));
+    }
+    if (!length)
+        return StringImpl::empty();
+    UCharBuffer buf = {s, length}; 
+    pair<HashSet<StringImpl*>::iterator, bool> addResult = globalData->identifierTable->add<UCharBuffer, IdentifierUCharBufferTranslator>(buf);
+
+    // If the string is newly-translated, then we need to adopt it.
+    // The boolean in the pair tells us if that is so.
+    return addResult.second ? adoptRef(*addResult.first) : *addResult.first;
+}
+
+PassRefPtr<StringImpl> Identifier::add(ExecState* exec, const UChar* s, int length)
+{
+    return add(&exec->globalData(), s, length);
+}
+
+PassRefPtr<StringImpl> Identifier::addSlowCase(JSGlobalData* globalData, StringImpl* r)
+{
+    ASSERT(!r->isIdentifier());
+    // The empty & null strings are static singletons, and static strings are handled
+    // in ::add() in the header, so we should never get here with a zero length string.
+    ASSERT(r->length());
+
+    if (r->length() == 1) {
+        UChar c = r->characters()[0];
+        if (c <= 0xFF)
+            r = globalData->smallStrings.singleCharacterStringRep(c);
+            if (r->isIdentifier())
+                return r;
+    }
+
+    return *globalData->identifierTable->add(r).first;
+}
+
+PassRefPtr<StringImpl> Identifier::addSlowCase(ExecState* exec, StringImpl* r)
+{
+    return addSlowCase(&exec->globalData(), r);
+}
+
+Identifier Identifier::from(ExecState* exec, unsigned value)
+{
+    return Identifier(exec, exec->globalData().numericStrings.add(value));
+}
+
+Identifier Identifier::from(ExecState* exec, int value)
+{
+    return Identifier(exec, exec->globalData().numericStrings.add(value));
+}
+
+Identifier Identifier::from(ExecState* exec, double value)
+{
+    return Identifier(exec, exec->globalData().numericStrings.add(value));
+}
+
+Identifier Identifier::from(JSGlobalData* globalData, unsigned value)
+{
+    return Identifier(globalData, globalData->numericStrings.add(value));
+}
+
+Identifier Identifier::from(JSGlobalData* globalData, int value)
+{
+    return Identifier(globalData, globalData->numericStrings.add(value));
+}
+
+Identifier Identifier::from(JSGlobalData* globalData, double value)
+{
+    return Identifier(globalData, globalData->numericStrings.add(value));
+}
+
+#ifndef NDEBUG
+
+void Identifier::checkCurrentIdentifierTable(JSGlobalData* globalData)
+{
+    // Check the identifier table accessible through the threadspecific matches the
+    // globalData's identifier table.
+    ASSERT_UNUSED(globalData, globalData->identifierTable == wtfThreadData().currentIdentifierTable());
+}
+
+void Identifier::checkCurrentIdentifierTable(ExecState* exec)
+{
+    checkCurrentIdentifierTable(&exec->globalData());
+}
+
+#else
+
+// These only exists so that our exports are the same for debug and release builds.
+// This would be an ASSERT_NOT_REACHED(), but we're in NDEBUG only code here!
+void Identifier::checkCurrentIdentifierTable(JSGlobalData*) { CRASH(); }
+void Identifier::checkCurrentIdentifierTable(ExecState*) { CRASH(); }
+
+#endif
+
+} // namespace JSC