Changeset 255659 in webkit for trunk/Source/JavaScriptCore/parser/VariableEnvironment.h

Timestamp:

Feb 3, 2020, 8:22:29 PM (5 years ago)

Author:

[email protected]

Message:

[JSC] Use PackedPtr for VariableEnvironment
​https://bugs.webkit.org/show_bug.cgi?id=207172

Reviewed by Mark Lam.

Since VariableEnvironment's KeyValue is key: pointer + value: 2 byte, using PackedPtr can make it 8 bytes, 50% reduction.

• parser/VariableEnvironment.h:
• runtime/CachedTypes.cpp:

(JSC::CachedRefPtr::encode):
(JSC::CachedRefPtr::decode const): CachedTypes should handle PackedPtr too since VariableEnvironment starts using it.

File:

• trunk/Source/JavaScriptCore/parser/VariableEnvironment.h (modified) (2 diffs)

trunk/Source/JavaScriptCore/parser/VariableEnvironment.h

@@ -86 +86 @@
 class VariableEnvironment {
 private:
-    typedef HashMap<RefPtr<UniquedStringImpl>, VariableEnvironmentEntry, IdentifierRepHash, HashTraits<RefPtr<UniquedStringImpl>>, VariableEnvironmentEntryHashTraits> Map;
+    typedef HashMap<PackedRefPtr<UniquedStringImpl>, VariableEnvironmentEntry, IdentifierRepHash, HashTraits<RefPtr<UniquedStringImpl>>, VariableEnvironmentEntryHashTraits> Map;
 public:
     VariableEnvironment() = default;
@@ -140 +140 @@
     CompactVariableEnvironment() = default;
 
-    Vector<RefPtr<UniquedStringImpl>> m_variables;
+    Vector<PackedRefPtr<UniquedStringImpl>> m_variables;
     Vector<VariableEnvironmentEntry> m_variableMetadata;
     unsigned m_hash;