Harden Function()'s parsing of function literals.

src/compiler.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 22 matching lines @@
 #include "zone.h"
 
 namespace v8 {
 namespace internal {
 
 static const int kPrologueOffsetNotSet = -1;
 
 class ScriptDataImpl;
 class HydrogenCodeStub;
 
+// ParseRestriction is used to restrict the set of valid statements in a
+// unit of compilation.  Restriction violations cause a syntax error.
+enum ParseRestriction {
+  NO_PARSE_RESTRICTION,         // All expressions are allowed.
+  ONLY_SINGLE_FUNCTION_LITERAL  // Only a single FunctionLiteral expression.
+};
+
 // CompilationInfo encapsulates some information known at compile time.  It
 // is constructed based on the resources available at compile-time.
 class CompilationInfo {
  public:
   CompilationInfo(Handle<Script> script, Zone* zone);
   CompilationInfo(Handle<SharedFunctionInfo> shared_info, Zone* zone);
   CompilationInfo(Handle<JSFunction> closure, Zone* zone);
   CompilationInfo(HydrogenCodeStub* stub, Isolate* isolate, Zone* zone);
 
   ~CompilationInfo();
 
   Isolate* isolate() {
     ASSERT(Isolate::Current() == isolate_);
     return isolate_;
   }
-  Zone* zone() {
-    return zone_;
-  }
+  Zone* zone() { return zone_; }
   bool is_lazy() const { return IsLazy::decode(flags_); }
   bool is_eval() const { return IsEval::decode(flags_); }
   bool is_global() const { return IsGlobal::decode(flags_); }
   bool is_classic_mode() const { return language_mode() == CLASSIC_MODE; }
   bool is_extended_mode() const { return language_mode() == EXTENDED_MODE; }
   LanguageMode language_mode() const {
     return LanguageModeField::decode(flags_);
   }
   bool is_in_loop() const { return IsInLoop::decode(flags_); }
   FunctionLiteral* function() const { return function_; }
@@ skipping 60 matching lines @@
   }
 
   void MarkAsSavesCallerDoubles() {
     flags_ |= SavesCallerDoubles::encode(true);
   }
 
   bool saves_caller_doubles() const {
     return SavesCallerDoubles::decode(flags_);
   }
 
+  void SetParseRestriction(ParseRestriction restriction) {
+    flags_ = ParseRestricitonField::update(flags_, restriction);
+  }
+
+  ParseRestriction parse_restriction() const {
+    return ParseRestricitonField::decode(flags_);
+  }
+
   void SetFunction(FunctionLiteral* literal) {
     ASSERT(function_ == NULL);
     function_ = literal;
   }
   void SetScope(Scope* scope) {
     ASSERT(scope_ == NULL);
     scope_ = scope;
   }
   void SetGlobalScope(Scope* global_scope) {
     ASSERT(global_scope_ == NULL);
@@ skipping 127 matching lines @@
   // initial mode setting.
   class IsCompilingForDebugging: public BitField<bool, 8, 1> {};
   // If the compiled code contains calls that require building a frame
   class IsCalling: public BitField<bool, 9, 1> {};
   // If the compiled code contains calls that require building a frame
   class IsDeferredCalling: public BitField<bool, 10, 1> {};
   // If the compiled code contains calls that require building a frame
   class IsNonDeferredCalling: public BitField<bool, 11, 1> {};
   // If the compiled code saves double caller registers that it clobbers.
   class SavesCallerDoubles: public BitField<bool, 12, 1> {};
-
+  // If the set of valid statements is restricted.
+  class ParseRestricitonField: public BitField<ParseRestriction, 13, 1> {};
 
   unsigned flags_;
 
   // Fields filled in by the compilation pipeline.
   // AST filled in by the parser.
   FunctionLiteral* function_;
   // The scope of the function literal as a convenience.  Set to indicate
   // that scopes have been analyzed.
   Scope* scope_;
   // The global scope provided as a convenience.
@@ skipping 196 matching lines @@
                                             v8::Extension* extension,
                                             ScriptDataImpl* pre_data,
                                             Handle<Object> script_data,
                                             NativesFlag is_natives_code);
 
   // Compile a String source within a context for Eval.
   static Handle<SharedFunctionInfo> CompileEval(Handle<String> source,
                                                 Handle<Context> context,
                                                 bool is_global,
                                                 LanguageMode language_mode,
+                                                ParseRestriction restriction,
                                                 int scope_position);
 
   // Compile from function info (used for lazy compilation). Returns true on
   // success and false if the compilation resulted in a stack overflow.
   static bool CompileLazy(CompilationInfo* info);
 
   static void RecompileParallel(Handle<JSFunction> function);
 
   // Compile a shared function info object (the function is possibly lazily
   // compiled).
@@ skipping 14 matching lines @@
 
   static void RecordFunctionCompilation(Logger::LogEventsAndTags tag,
                                         CompilationInfo* info,
                                         Handle<SharedFunctionInfo> shared);
 };
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_COMPILER_H_