Introduce extended mode.

src/objects.h

 // Copyright 2011 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 3023 matching lines @@
 class ScopeInfo : public FixedArray {
  public:
   static inline ScopeInfo* cast(Object* object);
 
   // Return the type of this scope.
   ScopeType Type();
 
   // Does this scope call eval?
   bool CallsEval();
 
-  // Is this scope a strict mode scope?
-  bool IsStrictMode();
+  // Return the language mode of this scope.
+  LanguageMode language_mode();
 
   // Does this scope make a non-strict eval call?
   bool CallsNonStrictEval() {
-    return CallsEval() && !IsStrictMode();
+    return CallsEval() && (language_mode() == CLASSIC_MODE);
   }
 
   // Return the total number of locals allocated on the stack and in the
   // context. This includes the parameters that are allocated in the context.
   int LocalCount();
 
   // Return the number of stack slots for code. This number consists of two
   // parts:
   //  1. One stack slot per stack allocated local.
   //  2. One stack slot for the function name if it is stack allocated.
@@ skipping 147 matching lines @@
   enum FunctionVariableInfo {
     NONE,     // No function name present.
     STACK,    // Function
     CONTEXT,
     UNUSED
   };
 
   // Properties of scopes.
   class TypeField:             public BitField<ScopeType,            0, 3> {};
   class CallsEvalField:        public BitField<bool,                 3, 1> {};
-  class StrictModeField:       public BitField<bool,                 4, 1> {};
-  class FunctionVariableField: public BitField<FunctionVariableInfo, 5, 2> {};
-  class FunctionVariableMode:  public BitField<VariableMode,         7, 3> {};
+  class LanguageModeField:     public BitField<LanguageMode,         4, 2> {};
+  class FunctionVariableField: public BitField<FunctionVariableInfo, 6, 2> {};
+  class FunctionVariableMode:  public BitField<VariableMode,         8, 3> {};
 
   // BitFields representing the encoded information for context locals in the
   // ContextLocalInfoEntries part.
   class ContextLocalMode:      public BitField<VariableMode,         0, 3> {};
   class ContextLocalInitFlag:  public BitField<InitializationFlag,   3, 1> {};
 };
 
 
 // The cache for maps used by normalized (dictionary mode) objects.
 // Such maps do not have property descriptors, so a typical program
@@ skipping 1733 matching lines @@
   // from the stack or compilation cache.
   inline int code_age();
   inline void set_code_age(int age);
 
   // Indicates whether optimizations have been disabled for this
   // shared function info. If a function is repeatedly optimized or if
   // we cannot optimize the function we disable optimization to avoid
   // spending time attempting to optimize it again.
   DECL_BOOLEAN_ACCESSORS(optimization_disabled)
 
-  // Indicates whether the function is a strict mode function.
-  inline bool strict_mode();
+  // Indicates whether the function is a classic mode function.

[Rico, 2011/11/15 08:25:07]

I would add "(i.e., classic in the sense that we have non-strict semantics)"
after classic in this comment. V8 team members might not actually know what
classic means yet, so a clarification here would be good)

[Steven, 2011/11/15 13:33:30]

Done.

+  inline bool is_classic_mode();
 
-  // Indicates the mode of the function.
-  inline StrictModeFlag strict_mode_flag();
-  inline void set_strict_mode_flag(StrictModeFlag strict_mode_flag);
+  // Indicates whether the function is an extended mode function.
+  inline bool is_extended_mode();

[Rico, 2011/11/15 08:25:07]

Also, please add a comment here (or below for language_mode()) explaining the
meaning of the 3 modes, I know this is in the commit message, but it is
cumbersome to go there. Please also do this in globals.h

[Steven, 2011/11/15 13:33:30]

Done.

+
+  // Indicates the language mode of the function.
+  inline LanguageMode language_mode();
+  inline void set_language_mode(LanguageMode language_mode);
 
   // False if the function definitely does not allocate an arguments object.
   DECL_BOOLEAN_ACCESSORS(uses_arguments)
 
   // True if the function has any duplicated parameter names.
   DECL_BOOLEAN_ACCESSORS(has_duplicate_parameters)
 
   // Indicates whether the function is a native function.
   // These needs special treatment in .call and .apply since
   // null passed as the receiver should not be translated to the
@@ skipping 202 matching lines @@
   static const int kCodeAgeSize = 3;
   static const int kCodeAgeMask = (1 << kCodeAgeSize) - 1;
 
   enum CompilerHints {
     kHasOnlySimpleThisPropertyAssignments,
     kAllowLazyCompilation,
     kLiveObjectsMayExist,
     kCodeAgeShift,
     kOptimizationDisabled = kCodeAgeShift + kCodeAgeSize,
     kStrictModeFunction,
+    kExtendedModeFunction,
     kUsesArguments,
     kHasDuplicateParameters,
     kNative,
     kBoundFunction,
     kIsAnonymous,
     kNameShouldPrintAsAnonymous,
     kCompilerHintsCount  // Pseudo entry
   };
 
  private:
@@ skipping 10 matching lines @@
   STATIC_ASSERT(SharedFunctionInfo::kCompilerHintsCount <=
                 SharedFunctionInfo::kCompilerHintsSize * kBitsPerByte);
 
  public:
   // Constants for optimizing codegen for strict mode function and
   // native tests.
   // Allows to use byte-width instructions.
   static const int kStrictModeBitWithinByte =
       (kStrictModeFunction + kCompilerHintsSmiTagSize) % kBitsPerByte;
 
+  static const int kExtendedModeBitWithinByte =
+      (kExtendedModeFunction + kCompilerHintsSmiTagSize) % kBitsPerByte;
+
   static const int kNativeBitWithinByte =
       (kNative + kCompilerHintsSmiTagSize) % kBitsPerByte;
 
 #if __BYTE_ORDER == __LITTLE_ENDIAN
   static const int kStrictModeByteOffset = kCompilerHintsOffset +
       (kStrictModeFunction + kCompilerHintsSmiTagSize) / kBitsPerByte;
+  static const int kExtendedModeByteOffset = kCompilerHintsOffset +
+      (kExtendedModeFunction + kCompilerHintsSmiTagSize) / kBitsPerByte;
   static const int kNativeByteOffset = kCompilerHintsOffset +
       (kNative + kCompilerHintsSmiTagSize) / kBitsPerByte;
 #elif __BYTE_ORDER == __BIG_ENDIAN
   static const int kStrictModeByteOffset = kCompilerHintsOffset +
       (kCompilerHintsSize - 1) -
       ((kStrictModeFunction + kCompilerHintsSmiTagSize) / kBitsPerByte);
+  static const int kExtendedModeByteOffset = kCompilerHintsOffset +
+      (kCompilerHintsSize - 1) -
+      ((kExtendedModeFunction + kCompilerHintsSmiTagSize) / kBitsPerByte);
   static const int kNativeByteOffset = kCompilerHintsOffset +
       (kCompilerHintsSize - 1) -
       ((kNative + kCompilerHintsSmiTagSize) / kBitsPerByte);
 #else
 #error Unknown byte ordering
 #endif
 
  private:
   DISALLOW_IMPLICIT_CONSTRUCTORS(SharedFunctionInfo);
 };
@@ skipping 596 matching lines @@
 };
 
 
 class CompilationCacheTable: public HashTable<CompilationCacheShape,
                                               HashTableKey*> {
  public:
   // Find cached value for a string key, otherwise return null.
   Object* Lookup(String* src);
   Object* LookupEval(String* src,
                      Context* context,
-                     StrictModeFlag strict_mode,
+                     LanguageMode language_mode,
                      int scope_position);
   Object* LookupRegExp(String* source, JSRegExp::Flags flags);
   MaybeObject* Put(String* src, Object* value);
   MaybeObject* PutEval(String* src,
                        Context* context,
                        SharedFunctionInfo* value,
                        int scope_position);
   MaybeObject* PutRegExp(String* src, JSRegExp::Flags flags, FixedArray* value);
 
   // Remove given value from cache.
@@ skipping 2005 matching lines @@
     } else {
       value &= ~(1 << bit_position);
     }
     return value;
   }
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_OBJECTS_H_