Changeset 59587 in webkit for trunk/JavaScriptCore/runtime/Executable.h

Timestamp:

May 16, 2010, 6:02:33 PM (15 years ago)

Author:

Simon Fraser

Message:

2010-05-16 Simon Fraser <Simon Fraser>

Reviewed by Darin Adler.

Reduce the size of FunctionExecutable
​https://bugs.webkit.org/show_bug.cgi?id=39180

Change m_numVariables from a size_t to 31 bits in a bitfield,
packed with another bit for m_forceUsesArguments (which in turn
get packed with the base class).

Reduces the size of FunctionExecutable from 160 to 152 bytes.

• runtime/Executable.h: (JSC::FunctionExecutable::variableCount): (JSC::FunctionExecutable::FunctionExecutable):

File:

• trunk/JavaScriptCore/runtime/Executable.h (modified) (6 diffs)

trunk/JavaScriptCore/runtime/Executable.h

@@ -320 +320 @@
         const Identifier& name() { return m_name; }
         size_t parameterCount() const { return m_parameters->size(); }
-        size_t variableCount() const { return m_numVariables; }
+        unsigned variableCount() const { return m_numVariables; }
         UString paramString() const;
         SharedSymbolTable* symbolTable() const { return m_symbolTable; }
@@ -332 +332 @@
         FunctionExecutable(JSGlobalData* globalData, const Identifier& name, const SourceCode& source, bool forceUsesArguments, FunctionParameters* parameters, int firstLine, int lastLine)
             : ScriptExecutable(globalData, source)
+            , m_numVariables(0)
             , m_forceUsesArguments(forceUsesArguments)
             , m_parameters(parameters)
@@ -337 +338 @@
             , m_codeBlockForConstruct(0)
             , m_name(name)
-            , m_numVariables(0)
             , m_symbolTable(0)
         {
@@ -346 +346 @@
         FunctionExecutable(ExecState* exec, const Identifier& name, const SourceCode& source, bool forceUsesArguments, FunctionParameters* parameters, int firstLine, int lastLine)
             : ScriptExecutable(exec, source)
+            , m_numVariables(0)
             , m_forceUsesArguments(forceUsesArguments)
             , m_parameters(parameters)
@@ -351 +352 @@
             , m_codeBlockForConstruct(0)
             , m_name(name)
-            , m_numVariables(0)
             , m_symbolTable(0)
         {
@@ -361 +361 @@
         void compileForConstruct(ExecState*, ScopeChainNode*);
 
-        bool m_forceUsesArguments;
+        unsigned m_numVariables : 31;
+        bool m_forceUsesArguments : 1;
+
         RefPtr<FunctionParameters> m_parameters;
         FunctionCodeBlock* m_codeBlockForCall;
         FunctionCodeBlock* m_codeBlockForConstruct;
         Identifier m_name;
-        size_t m_numVariables;
         SharedSymbolTable* m_symbolTable;