Changeset 293757 in webkit

Timestamp:

May 3, 2022, 7:27:25 PM (4 years ago)

Author:

ysuzuki@apple.com

Message:

[JSC] Initialize empty and null AtomString at compile time
​https://bugs.webkit.org/show_bug.cgi?id=240031

Reviewed by Mark Lam.

Because they are initialized from static data, we can just initialize them
at compile time, and we do not need to have AtomString::init.

• Source/WebKit/WebAuthnProcess/WebAuthnProcess.cpp:

(WebKit::WebAuthnProcess::initializeWebAuthnProcess):

• Source/WTF/wtf/Threading.cpp:

(WTF::initialize):

• Source/WTF/wtf/text/AtomString.cpp:

(WTF::AtomString::init): Deleted.

• Source/WTF/wtf/text/AtomString.h:

(WTF::StaticAtomString::StaticAtomString):
(WTF::nullAtom):
(WTF::emptyAtom):

• Source/WebCore/dom/make_names.pl:

(printInit):

Canonical link: ​https://commits.webkit.org/250236@main

Location:

trunk/Source

Files:

• WTF/ChangeLog (modified) (1 diff)
• WTF/wtf/Threading.cpp (modified) (1 diff)
• WTF/wtf/text/AtomString.cpp (modified) (2 diffs)
• WTF/wtf/text/AtomString.h (modified) (2 diffs)
• WebCore/ChangeLog (modified) (1 diff)
• WebCore/dom/QualifiedName.cpp (modified) (1 diff)
• WebCore/dom/make_names.pl (modified) (1 diff)
• WebKit/ChangeLog (modified) (1 diff)
• WebKit/WebAuthnProcess/WebAuthnProcess.cpp (modified) (1 diff)

trunk/Source/WTF/ChangeLog

@@ +1 @@
+2022-05-03  Yusuke Suzuki  <ysuzuki@apple.com>
+
+        [JSC] Initialize empty and null AtomString at compile time
+        https://bugs.webkit.org/show_bug.cgi?id=240031
+
+        Reviewed by Mark Lam.
+
+        Because they are initialized from static data, we can just initialize them
+        at compile time, and we do not need to have `AtomString::init`.
+
+        * wtf/Threading.cpp:
+        (WTF::initialize):
+        * wtf/text/AtomString.cpp:
+        (WTF::AtomString::init): Deleted.
+        * wtf/text/AtomString.h:
+        (WTF::StaticAtomString::StaticAtomString):
+        (WTF::nullAtom):
+        (WTF::emptyAtom):
+
 2022-05-03  Chris Dumez  <cdumez@apple.com>
 

trunk/Source/WTF/wtf/Threading.cpp

@@ -476 +476 @@
         SignalHandlers::initialize();
 #endif
-        AtomString::init();
     });
 }

trunk/Source/WTF/wtf/text/AtomString.cpp

@@ -32 +32 @@
 
 namespace WTF {
+
+WTF_EXPORT_PRIVATE const StaticAtomString nullAtomData { nullptr };
+WTF_EXPORT_PRIVATE const StaticAtomString emptyAtomData { &StringImpl::s_emptyAtomString };
 
 template<AtomString::CaseConvertType type>
@@ -135 +138 @@
 #endif
 
-WTF_EXPORT_PRIVATE LazyNeverDestroyed<const AtomString> nullAtomData;
-WTF_EXPORT_PRIVATE LazyNeverDestroyed<const AtomString> emptyAtomData;
-
-void AtomString::init()
-{
-    static std::once_flag initializeKey;
-    std::call_once(initializeKey, [] {
-        nullAtomData.construct();
-        emptyAtomData.construct(AtomString::fromLatin1(""));
-    });
-}
-
 static inline StringBuilder replaceUnpairedSurrogatesWithReplacementCharacterInternal(StringView view)
 {

trunk/Source/WTF/wtf/text/AtomString.h

@@ -36 +36 @@
     WTF_MAKE_FAST_ALLOCATED;
 public:
-    WTF_EXPORT_PRIVATE static void init();
-
     AtomString();
     AtomString(const LChar*, unsigned length);
@@ -280 +278 @@
 #endif
 
-// nullAtom and emptyAtom are special AtomString. They can be used from any threads since their StringImpls are not actually registered into AtomStringTable.
-extern WTF_EXPORT_PRIVATE LazyNeverDestroyed<const AtomString> nullAtomData;
-extern WTF_EXPORT_PRIVATE LazyNeverDestroyed<const AtomString> emptyAtomData;
-
-inline const AtomString& nullAtom() { return nullAtomData.get(); }
-inline const AtomString& emptyAtom() { return emptyAtomData.get(); }
+struct StaticAtomString {
+    constexpr StaticAtomString(StringImpl::StaticStringImpl* pointer)
+        : m_pointer(pointer)
+    {
+    }
+
+    StringImpl::StaticStringImpl* m_pointer;
+};
+static_assert(sizeof(AtomString) == sizeof(StaticAtomString), "AtomString and StaticAtomString must be the same size!");
+extern WTF_EXPORT_PRIVATE const StaticAtomString nullAtomData;
+extern WTF_EXPORT_PRIVATE const StaticAtomString emptyAtomData;
+
+inline const AtomString& nullAtom() { return *reinterpret_cast<const AtomString*>(&nullAtomData); }
+inline const AtomString& emptyAtom() { return *reinterpret_cast<const AtomString*>(&emptyAtomData); }
 
 inline AtomString::AtomString(ASCIILiteral literal)

trunk/Source/WebCore/ChangeLog

@@ +1 @@
+2022-05-03  Yusuke Suzuki  <ysuzuki@apple.com>
+
+        [JSC] Initialize empty and null AtomString at compile time
+        https://bugs.webkit.org/show_bug.cgi?id=240031
+
+        Reviewed by Mark Lam.
+
+        * dom/QualifiedName.cpp:
+        (WebCore::QualifiedName::init):
+        * dom/make_names.pl:
+        (printInit):
+
 2022-05-03  Sihui Liu  <sihui_liu@apple.com>
 

trunk/Source/WebCore/dom/QualifiedName.cpp

@@ -50 +50 @@
         return;
 
-    ASSERT_WITH_MESSAGE(WTF::nullAtomData.isConstructed(), "AtomString::init should have been called");
     anyName.construct(nullAtom(), starAtom(), starAtom());
     initialized = true;

trunk/Source/WebCore/dom/make_names.pl

@@ -603 +603 @@
 
     // Use placement new to initialize the globals.
-
-    AtomString::init();
 ";
 }

trunk/Source/WebKit/ChangeLog

@@ +1 @@
+2022-05-03  Yusuke Suzuki  <ysuzuki@apple.com>
+
+        [JSC] Initialize empty and null AtomString at compile time
+        https://bugs.webkit.org/show_bug.cgi?id=240031
+
+        Reviewed by Mark Lam.
+
+        * WebAuthnProcess/WebAuthnProcess.cpp:
+        (WebKit::WebAuthnProcess::initializeWebAuthnProcess):
+
 2022-05-03  Commit Queue  <commit-queue@webkit.org>
 

trunk/Source/WebKit/WebAuthnProcess/WebAuthnProcess.cpp

@@ -95 +95 @@
     applyProcessCreationParameters(parameters.auxiliaryProcessParameters);
     WTF::Thread::setCurrentThreadIsUserInitiated();
-    AtomString::init();
 }