From 1bf1084f2b10c3b47fd1a588d85d21ed0eb41d0c Mon Sep 17 00:00:00 2001 From: Lorry Tar Creator Date: Tue, 27 Jun 2017 06:07:23 +0000 Subject: webkitgtk-2.16.5 --- Source/WTF/wtf/text/SymbolImpl.cpp | 59 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 59 insertions(+) create mode 100644 Source/WTF/wtf/text/SymbolImpl.cpp (limited to 'Source/WTF/wtf/text/SymbolImpl.cpp') diff --git a/Source/WTF/wtf/text/SymbolImpl.cpp b/Source/WTF/wtf/text/SymbolImpl.cpp new file mode 100644 index 000000000..18ebea9e0 --- /dev/null +++ b/Source/WTF/wtf/text/SymbolImpl.cpp @@ -0,0 +1,59 @@ +/* + * Copyright (C) 2016 Yusuke Suzuki . + * + * 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. AND ITS CONTRIBUTORS ``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 ITS 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. + */ + +#include "config.h" +#include "SymbolImpl.h" + +namespace WTF { + +// In addition to the normal hash value, store specialized hash value for +// symbolized StringImpl*. And don't use the normal hash value for symbolized +// StringImpl* when they are treated as Identifiers. Unique nature of these +// symbolized StringImpl* keys means that we don't need them to match any other +// string (in fact, that's exactly the oposite of what we want!), and the +// normal hash would lead to lots of conflicts. +unsigned SymbolImpl::nextHashForSymbol() +{ + static unsigned s_nextHashForSymbol = 0; + s_nextHashForSymbol += 1 << s_flagCount; + s_nextHashForSymbol |= 1 << 31; + return s_nextHashForSymbol; +} + +Ref SymbolImpl::create(StringImpl& rep) +{ + auto* ownerRep = (rep.bufferOwnership() == BufferSubstring) ? rep.substringBuffer() : &rep; + ASSERT(ownerRep->bufferOwnership() != BufferSubstring); + if (rep.is8Bit()) + return adoptRef(*new SymbolImpl(rep.m_data8, rep.length(), *ownerRep)); + return adoptRef(*new SymbolImpl(rep.m_data16, rep.length(), *ownerRep)); +} + +Ref SymbolImpl::createNullSymbol() +{ + return adoptRef(*new SymbolImpl); +} + +} // namespace WTF -- cgit v1.2.1