Changeset 174606 in webkit for trunk/Source/JavaScriptCore/parser/Parser.h

Timestamp:

Oct 10, 2014, 12:03:20 PM (11 years ago)

Author:

[email protected]

Message:

Various arguments optimisations in codegen fail to account for arguments being in lexical record
​https://bugs.webkit.org/show_bug.cgi?id=137617

Reviewed by Michael Saboff.

Rework the way we track |arguments| references so that we don't try
to use the |arguments| reference on the stack if it's not safe.

To do this without nuking performance it was necessary to update
the parser to track modification of the |arguments| reference
itself.

• bytecode/CodeBlock.cpp:
• bytecompiler/BytecodeGenerator.cpp:

(JSC::BytecodeGenerator::BytecodeGenerator):
(JSC::BytecodeGenerator::willResolveToArguments):
(JSC::BytecodeGenerator::uncheckedLocalArgumentsRegister):
(JSC::BytecodeGenerator::emitCall):
(JSC::BytecodeGenerator::emitConstruct):
(JSC::BytecodeGenerator::emitEnumeration):
(JSC::BytecodeGenerator::uncheckedRegisterForArguments): Deleted.

• bytecompiler/BytecodeGenerator.h:

(JSC::BytecodeGenerator::hasSafeLocalArgumentsRegister):

• bytecompiler/NodesCodegen.cpp:

(JSC::BracketAccessorNode::emitBytecode):
(JSC::DotAccessorNode::emitBytecode):
(JSC::getArgumentByVal):
(JSC::CallFunctionCallDotNode::emitBytecode):
(JSC::ApplyFunctionCallDotNode::emitBytecode):
(JSC::ArrayPatternNode::emitDirectBinding):

• interpreter/StackVisitor.cpp:

(JSC::StackVisitor::Frame::existingArguments):

• parser/Nodes.h:

(JSC::ScopeNode::modifiesArguments):

• parser/Parser.cpp:

(JSC::Parser<LexerType>::parseInner):

• parser/Parser.h:

(JSC::Scope::getCapturedVariables):

• parser/ParserModes.h:

File:

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

trunk/Source/JavaScriptCore/parser/Parser.h

@@ -280 +280 @@
     }
 
-    void getCapturedVariables(IdentifierSet& capturedVariables, bool& modifiedParameter)
+    void getCapturedVariables(IdentifierSet& capturedVariables, bool& modifiedParameter, bool& modifiedArguments)
     {
         if (m_needsFullActivation || m_usesEval) {
@@ -293 +293 @@
         }
         modifiedParameter = false;
+        if (shadowsArguments())
+            modifiedArguments = true;
         if (m_declaredParameters.size()) {
             IdentifierSet::iterator end = m_writtenVariables.end();
             for (IdentifierSet::iterator ptr = m_writtenVariables.begin(); ptr != end; ++ptr) {
+                if (*ptr == m_vm->propertyNames->arguments.impl())
+                    modifiedArguments = true;
                 if (!m_declaredParameters.contains(*ptr))
                     continue;