tree 7efc195e14c2daa09bd39ec77fc05673ab961d13
parent 6703e6b50f83ecf6db9019f84130bc98818aa400
author ysuzuki@apple.com <ysuzuki@apple.com@268f45cc-cd09-0410-ab3c-d52691b4dbfc> 1579644343 +0000
committer ysuzuki@apple.com <ysuzuki@apple.com@268f45cc-cd09-0410-ab3c-d52691b4dbfc> 1579644343 +0000

[WTF] AtomStringTable should be small
https://bugs.webkit.org/show_bug.cgi?id=206400

Reviewed by Sam Weinig.

Source/WebCore:

* dom/GCReachableRef.h:
(WebCore::GCReachableRef::GCReachableRef):
* dom/QualifiedName.h:
(WebCore::QualifiedName::hashTableDeletedValue):

Source/WTF:

AtomStringTable is the largest hashtable typically. It takes more
than 256KB per WebProcess (sometimes, it took 1MB or more).
This patch leverages PackedPtr to compact it from 8 bytes per entry
to 6 bytes per entry.

While this is still large, we should investigate how to compact C++
pointers in 4 bytes[1] to shrink memory footprint, since WebKit
memory is used by Vector and HashTable fulfilled with pointers.

[1]: https://bugs.webkit.org/show_bug.cgi?id=206469

* wtf/DumbPtrTraits.h:
(WTF::DumbPtrTraits::hashTableDeletedValue):
(WTF::DumbPtrTraits::isHashTableDeletedValue):
* wtf/Forward.h:
* wtf/HashTraits.h:
* wtf/Packed.h:
(WTF::Packed<T::Packed):
(WTF::Packed<T::isHashTableDeletedValue const):
(WTF::GetPtrHelper<PackedPtr<T>>::getPtr):
(WTF::PackedPtrTraits::hashTableDeletedValue):
(WTF::PackedPtrTraits::isHashTableDeletedValue):
(WTF::alignof): Deleted.
* wtf/Ref.h:
(WTF::Ref::Ref):
(WTF::Ref::isHashTableDeletedValue const):
(WTF::Ref::hashTableDeletedValue): Deleted.
* wtf/RefPtr.h:
(WTF::RefPtr::RefPtr):
(WTF::RefPtr::isHashTableDeletedValue const):
(WTF::RefPtr::hashTableDeletedValue): Deleted.
* wtf/text/AtomStringImpl.cpp:
(WTF::addToStringTable):
(WTF::CStringTranslator::equal):
(WTF::CStringTranslator::translate):
(WTF::UCharBufferTranslator::equal):
(WTF::UCharBufferTranslator::translate):
(WTF::HashAndUTF8CharactersTranslator::equal):
(WTF::HashAndUTF8CharactersTranslator::translate):
(WTF::SubstringTranslator::translate):
(WTF::SubstringTranslator8::equal):
(WTF::SubstringTranslator16::equal):
(WTF::LCharBufferTranslator::equal):
(WTF::LCharBufferTranslator::translate):
(WTF::BufferFromStaticDataTranslator::equal):
(WTF::BufferFromStaticDataTranslator::translate):
(WTF::AtomStringImpl::addSlowCase):
(WTF::AtomStringImpl::remove):
(WTF::AtomStringImpl::lookUpSlowCase):
(WTF::AtomStringImpl::lookUp):
* wtf/text/AtomStringTable.cpp:
(WTF::AtomStringTable::~AtomStringTable):
* wtf/text/AtomStringTable.h:
(WTF::AtomStringTable::table):
(): Deleted.
* wtf/text/StringHash.h:
(WTF::StringHash::hash):
(WTF::StringHash::equal):
(WTF::ASCIICaseInsensitiveHash::hash):
(WTF::ASCIICaseInsensitiveHash::equal):
* wtf/text/StringImpl.h:

Tools:

* TestWebKitAPI/Tests/WTF/HashMap.cpp:
(TestWebKitAPI::TEST):
* TestWebKitAPI/Tests/WTF/HashSet.cpp:
(TestWebKitAPI::TEST):
* TestWebKitAPI/Tests/WTF/Packed.cpp:
(TestWebKitAPI::TEST):

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@254881 268f45cc-cd09-0410-ab3c-d52691b4dbfc