Changeset 42282 in webkit for trunk/JavaScriptCore/runtime/SmallStrings.cpp

Timestamp:

Apr 7, 2009, 2:15:33 PM (16 years ago)

Author:

[email protected]

Message:

2009-04-07 David Levin <​[email protected]>

Reviewed by Sam Weinig and Geoff Garen.

​https://bugs.webkit.org/show_bug.cgi?id=25039
UString refactoring to support UChar* sharing.

No change in sunspider perf.

• runtime/SmallStrings.cpp: (JSC::SmallStringsStorage::SmallStringsStorage):
• runtime/UString.cpp: (JSC::initializeStaticBaseString): (JSC::initializeUString): (JSC::UString::BaseString::isShared): Encapsulate the meaning behind the refcount == 1 checks because this needs to do slightly more when sharing is added. (JSC::concatenate): (JSC::UString::append): (JSC::UString::operator=):
• runtime/UString.h: Make m_baseString part of a union to get rid of casts, but make it protected because it is tricky to use it correctly since it is only valid when the Rep is not a BaseString. The void* will be filled in when sharing is added.

Add constructors due to the making members protected and it make ensuring proper
initialization work better (like in SmallStringsStorage).
(JSC::UString::Rep::create):
(JSC::UString::Rep::Rep):
(JSC::UString::Rep::):
(JSC::UString::BaseString::BaseString):
(JSC::UString::Rep::setBaseString):
(JSC::UString::Rep::baseString):

File:

• trunk/JavaScriptCore/runtime/SmallStrings.cpp (modified) (1 diff)

trunk/JavaScriptCore/runtime/SmallStrings.cpp

@@ -48 +48 @@
 
 SmallStringsStorage::SmallStringsStorage()
+    : m_base(m_characters, numCharactersToStore)
 {
-    for (unsigned i = 0; i < numCharactersToStore; ++i)
-        m_characters[i] = i;
-
     m_base.rc = numCharactersToStore + 1;
-    m_base.buf = m_characters;
-    m_base.len = numCharactersToStore;
-    m_base.offset = 0;
-    m_base._hash = 0;
-    m_base.m_baseString = 0;
-    m_base.preCapacity = 0;
-    m_base.usedPreCapacity = 0;
-    m_base.reportedCost = 0;
-
     // make sure UString doesn't try to reuse the buffer by pretending we have one more character in it
     m_base.usedCapacity = numCharactersToStore + 1;
     m_base.capacity = numCharactersToStore + 1;
     m_base.checkConsistency();
+
+    for (unsigned i = 0; i < numCharactersToStore; ++i)
+        m_characters[i] = i;
 
     memset(&m_reps, 0, sizeof(m_reps));