Attachment 362199 Details for Bug 194735 – Patch

[patch] Patch

bug-194735-20190215191440.patch (text/plain), 7.12 KB, created by Yusuke Suzuki on 2019-02-15 19:14:41 PST

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Creator: Yusuke Suzuki

Created: 2019-02-15 19:14:41 PST

Size: 7.12 KB

patch

obsolete

>Subversion Revision: 241638
>diff --git a/Source/JavaScriptCore/ChangeLog b/Source/JavaScriptCore/ChangeLog
>index 8049f0c376bf46d80c48aaca4760499ac0aafde8..b3e119ad2fc52d82866763cc607eb9c553149af9 100644
>--- a/Source/JavaScriptCore/ChangeLog
>+++ b/Source/JavaScriptCore/ChangeLog
>@@ -1,3 +1,28 @@
>+2019-02-15  Yusuke Suzuki  <ysuzuki@apple.com>
>+
>+        [JSC] Lazily create empty RegExp
>+        https://bugs.webkit.org/show_bug.cgi?id=194735
>+
>+        Reviewed by NOBODY (OOPS!).
>+
>+        Some scripts do not have any RegExp. In that case, allocating MarkedBlock for RegExp is costly.
>+        Previously, there was always one RegExp, "empty RegExp". This patch lazily creates it and drop
>+        one MarkedBlock.
>+
>+        * runtime/JSGlobalObject.cpp:
>+        (JSC::JSGlobalObject::init):
>+        * runtime/RegExpCache.cpp:
>+        (JSC::RegExpCache::ensureEmptyRegExpSlow):
>+        (JSC::RegExpCache::initialize): Deleted.
>+        * runtime/RegExpCache.h:
>+        (JSC::RegExpCache::ensureEmptyRegExp):
>+        (JSC::RegExpCache::emptyRegExp const): Deleted.
>+        * runtime/RegExpCachedResult.cpp:
>+        (JSC::RegExpCachedResult::lastResult):
>+        * runtime/RegExpCachedResult.h:
>+        * runtime/VM.cpp:
>+        (JSC::VM::VM):
>+
> 2019-02-15  Yusuke Suzuki  <ysuzuki@apple.com>
> 
>         [JSC] Make builtin objects more lazily initialized under non-JIT mode
>diff --git a/Source/JavaScriptCore/runtime/JSGlobalObject.cpp b/Source/JavaScriptCore/runtime/JSGlobalObject.cpp
>index c23c19257f4b297c78bdb2ebd0c558e5991c9453..d0c7ccdbfe3fa9ffb5ff9dd0082ba95bc3001958 100644
>--- a/Source/JavaScriptCore/runtime/JSGlobalObject.cpp
>+++ b/Source/JavaScriptCore/runtime/JSGlobalObject.cpp
>@@ -688,7 +688,7 @@ void JSGlobalObject::init(VM& vm)
>     m_arrayConstructor.set(vm, this, arrayConstructor);
>     
>     RegExpConstructor* regExpConstructor = RegExpConstructor::create(vm, RegExpConstructor::createStructure(vm, this, m_functionPrototype.get()), m_regExpPrototype.get(), m_speciesGetterSetter.get());
>-    m_regExpGlobalData.cachedResult().record(vm, this, vm.regExpCache()->emptyRegExp(), jsEmptyString(&vm), MatchResult(0, 0));
>+    m_regExpGlobalData.cachedResult().record(vm, this, nullptr, jsEmptyString(&vm), MatchResult(0, 0));
>     
>     JSArrayBufferConstructor* arrayBufferConstructor = JSArrayBufferConstructor::create(vm, JSArrayBufferConstructor::createStructure(vm, this, m_functionPrototype.get()), m_arrayBufferPrototype.get(), m_speciesGetterSetter.get());
>     m_arrayBufferPrototype->putDirectWithoutTransition(vm, vm.propertyNames->constructor, arrayBufferConstructor, static_cast<unsigned>(PropertyAttribute::DontEnum));
>diff --git a/Source/JavaScriptCore/runtime/RegExpCache.cpp b/Source/JavaScriptCore/runtime/RegExpCache.cpp
>index 2cb29c4023edb8940ca3666cd02aae9636e2f326..d76bb396297d46716949b39313b0f2acce9e48d1 100644
>--- a/Source/JavaScriptCore/runtime/RegExpCache.cpp
>+++ b/Source/JavaScriptCore/runtime/RegExpCache.cpp
>@@ -56,9 +56,11 @@ RegExpCache::RegExpCache(VM* vm)
> {
> }
> 
>-void RegExpCache::initialize(VM& vm)
>+RegExp* RegExpCache::ensureEmptyRegExpSlow(VM& vm)
> {
>-    m_emptyRegExp.set(vm, RegExp::create(vm, "", NoFlags));
>+    RegExp* regExp = RegExp::create(vm, "", NoFlags);
>+    m_emptyRegExp.set(vm, regExp);
>+    return regExp;
> }
> 
> void RegExpCache::finalize(Handle<Unknown> handle, void*)
>diff --git a/Source/JavaScriptCore/runtime/RegExpCache.h b/Source/JavaScriptCore/runtime/RegExpCache.h
>index 2f5bdc3c55186fb3f17e6c7822e4bc305983eae2..d5c540bf8b5b50c41bacf2a80b424d3e6cc7d420 100644
>--- a/Source/JavaScriptCore/runtime/RegExpCache.h
>+++ b/Source/JavaScriptCore/runtime/RegExpCache.h
>@@ -46,9 +46,12 @@ class RegExpCache : private WeakHandleOwner {
>     RegExpCache(VM* vm);
>     void deleteAllCode();
> 
>-    void initialize(VM&);
>-
>-    RegExp* emptyRegExp() const { return m_emptyRegExp.get(); }
>+    RegExp* ensureEmptyRegExp(VM& vm)
>+    {
>+        if (m_emptyRegExp)
>+            return m_emptyRegExp.get();
>+        return ensureEmptyRegExpSlow(vm);
>+    }
> 
> private:
>     
>@@ -58,6 +61,8 @@ class RegExpCache : private WeakHandleOwner {
> 
>     void finalize(Handle<Unknown>, void* context) override;
> 
>+    RegExp* ensureEmptyRegExpSlow(VM&);
>+
>     RegExp* lookupOrCreate(const WTF::String& patternString, RegExpFlags);
>     void addToStrongCache(RegExp*);
>     RegExpCacheMap m_weakCache; // Holds all regular expressions currently live.
>diff --git a/Source/JavaScriptCore/runtime/RegExpCachedResult.cpp b/Source/JavaScriptCore/runtime/RegExpCachedResult.cpp
>index c6a6b032dfa228ba583007387d676d79e8093bb1..9e100d2403c54da611b30a88c1b897356ce997aa 100644
>--- a/Source/JavaScriptCore/runtime/RegExpCachedResult.cpp
>+++ b/Source/JavaScriptCore/runtime/RegExpCachedResult.cpp
>@@ -45,8 +45,11 @@ void RegExpCachedResult::visitAggregate(SlotVisitor& visitor)
> 
> JSArray* RegExpCachedResult::lastResult(ExecState* exec, JSObject* owner)
> {
>+    VM& vm = exec->vm();
>     if (!m_reified) {
>-        m_reifiedInput.set(exec->vm(), owner, m_lastInput.get());
>+        m_reifiedInput.set(vm, owner, m_lastInput.get());
>+        if (!m_lastRegExp)
>+            m_lastRegExp.set(vm, owner, vm.regExpCache()->ensureEmptyRegExp(vm));
>         if (m_result)
>             m_reifiedResult.setWithoutWriteBarrier(createRegExpMatchesArray(exec, exec->lexicalGlobalObject(), m_lastInput.get(), m_lastRegExp.get(), m_result.start));
>         else
>@@ -54,7 +57,7 @@ JSArray* RegExpCachedResult::lastResult(ExecState* exec, JSObject* owner)
>         m_reifiedLeftContext.clear();
>         m_reifiedRightContext.clear();
>         m_reified = true;
>-        exec->vm().heap.writeBarrier(owner);
>+        vm.heap.writeBarrier(owner);
>     }
>     return m_reifiedResult.get();
> }
>diff --git a/Source/JavaScriptCore/runtime/RegExpCachedResult.h b/Source/JavaScriptCore/runtime/RegExpCachedResult.h
>index 88a6c663e713dac9d933d8d088a66efc011cc2d2..a5b039185ffa059212ea451b62da9325a6bc1ad3 100644
>--- a/Source/JavaScriptCore/runtime/RegExpCachedResult.h
>+++ b/Source/JavaScriptCore/runtime/RegExpCachedResult.h
>@@ -65,6 +65,8 @@ class RegExpCachedResult {
> 
>     void visitAggregate(SlotVisitor&);
> 
>+    // m_lastRegExp would be nullptr when RegExpCachedResult is not reified.
>+    // If we find m_lastRegExp is nullptr, it means this should hold the empty RegExp.
>     static ptrdiff_t offsetOfLastRegExp() { return OBJECT_OFFSETOF(RegExpCachedResult, m_lastRegExp); }
>     static ptrdiff_t offsetOfLastInput() { return OBJECT_OFFSETOF(RegExpCachedResult, m_lastInput); }
>     static ptrdiff_t offsetOfResult() { return OBJECT_OFFSETOF(RegExpCachedResult, m_result); }
>diff --git a/Source/JavaScriptCore/runtime/VM.cpp b/Source/JavaScriptCore/runtime/VM.cpp
>index 79022d62181168273e0e688b9b19a645b4baec69..0952ffefdf7cf6a19b4d5516b2e1f431f8b2915c 100644
>--- a/Source/JavaScriptCore/runtime/VM.cpp
>+++ b/Source/JavaScriptCore/runtime/VM.cpp
>@@ -401,7 +401,6 @@ VM::VM(VMType vmType, HeapType heapType)
>     sentinelSetBucket.set(*this, JSSet::BucketType::createSentinel(*this));
>     sentinelMapBucket.set(*this, JSMap::BucketType::createSentinel(*this));
> 
>-    m_regExpCache->initialize(*this);
>     smallStrings.initializeCommonStrings(*this);
> 
>     Thread::current().setCurrentAtomicStringTable(existingEntryAtomicStringTable);

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keith_miller: review+

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Attachments on bug 194735: 362199