Strict Mode assignment to read only property.

src/ic.h

 // Copyright 2006-2009 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 380 matching lines @@
   // Support for patching the map that is checked in an inlined
   // version of keyed load.
   static bool PatchInlinedLoad(Address address, Object* map);
 
   friend class IC;
 };
 
 
 class StoreIC: public IC {
  public:
-
-  enum StoreICStrictMode {
-    kStoreICNonStrict = kNonStrictMode,
-    kStoreICStrict = kStrictMode
-  };
-
   StoreIC() : IC(NO_EXTRA_FRAME) { ASSERT(target()->is_store_stub()); }
 
   MUST_USE_RESULT MaybeObject* Store(State state,
-                                     Code::ExtraICState extra_ic_state,
+                                     StrictModeFlag strict_mode,
                                      Handle<Object> object,
                                      Handle<String> name,
                                      Handle<Object> value);
 
   // Code generators for stub routines. Only called once at startup.
   static void GenerateInitialize(MacroAssembler* masm) { GenerateMiss(masm); }
   static void GenerateMiss(MacroAssembler* masm);
   static void GenerateMegamorphic(MacroAssembler* masm,
-                                  Code::ExtraICState extra_ic_state);
+                                  StrictModeFlag strict_mode);
   static void GenerateArrayLength(MacroAssembler* masm);
   static void GenerateNormal(MacroAssembler* masm);
-  static void GenerateGlobalProxy(MacroAssembler* masm);
+  static void GenerateGlobalProxy(MacroAssembler* masm, StrictModeFlag strict);
 
   // Clear the use of an inlined version.
   static void ClearInlinedVersion(Address address);
 
   // The offset from the inlined patch site to the start of the
   // inlined store instruction.
   static const int kOffsetToStoreInstruction;
 
  private:
   // Update the inline cache and the global stub cache based on the
   // lookup result.
   void UpdateCaches(LookupResult* lookup,
                     State state,
-                    Code::ExtraICState extra_ic_state,
+                    StrictModeFlag strict_mode,
                     Handle<JSObject> receiver,
                     Handle<String> name,
                     Handle<Object> value);
 
+  void set_target(Code* code) {
+    ASSERT(code->extra_ic_state() == target()->extra_ic_state());

[Lasse Reichstein, 2011/02/28 11:18:30]

If the "extra_ic_state" is only strict/non-strict, just call it strict_ic_state
and return the correct enum value directly. The way you use it seems to assume
that the value is exactly kStrictMode.
If we ever need more state, we can add more accessors.

[Vitaly Repeshko, 2011/02/28 11:35:05]

Please don't kill extra_ic_state. It's also used as an opaque extra state to
gather more type feedback. But having another accessor that wraps it is a
probably a good idea. 

[Martin Maly, 2011/03/01 01:40:29]

I am keeping the extra_ic_state but changing the condition to mask only for the
bit that this code cares about. This leaves the rest of the VM to use the other
bit.

+    IC::set_target(code);
+  }
+

[Martin Maly, 2011/02/27 23:04:04]

This is the 2nd check that StoreIC doesn't switch strictness as it gets updated.

I like this check because it only affects StoreIC (or KeyedStoreIC below) but it
is still a bit removed from the actual patching. Plus it uses method shadowing
so it is a bit more fragile than the other test.

   // Stub accessors.
   static Code* megamorphic_stub() {
     return Builtins::builtin(Builtins::StoreIC_Megamorphic);
   }
   static Code* megamorphic_stub_strict() {
     return Builtins::builtin(Builtins::StoreIC_Megamorphic_Strict);
   }
   static Code* initialize_stub() {
     return Builtins::builtin(Builtins::StoreIC_Initialize);
   }
@@ skipping 15 matching lines @@
 
   friend class IC;
 };
 
 
 class KeyedStoreIC: public IC {
  public:
   KeyedStoreIC() : IC(NO_EXTRA_FRAME) { }
 
   MUST_USE_RESULT MaybeObject* Store(State state,
+                                     StrictModeFlag strict_mode,
                                      Handle<Object> object,
                                      Handle<Object> name,
                                      Handle<Object> value);
 
   // Code generators for stub routines.  Only called once at startup.
   static void GenerateInitialize(MacroAssembler* masm) { GenerateMiss(masm); }
   static void GenerateMiss(MacroAssembler* masm);
-  static void GenerateRuntimeSetProperty(MacroAssembler* masm);
-  static void GenerateGeneric(MacroAssembler* masm);
+  static void GenerateRuntimeSetProperty(MacroAssembler* masm,
+                                         StrictModeFlag strict_mode);
+  static void GenerateGeneric(MacroAssembler* masm, StrictModeFlag strict_mode);
 
   // Clear the inlined version so the IC is always hit.
   static void ClearInlinedVersion(Address address);
 
   // Restore the inlined version so the fast case can get hit.
   static void RestoreInlinedVersion(Address address);
 
  private:
   // Update the inline cache.
   void UpdateCaches(LookupResult* lookup,
                     State state,
+                    StrictModeFlag strict_mode,
                     Handle<JSObject> receiver,
                     Handle<String> name,
                     Handle<Object> value);
 
+  void set_target(Code* code) {
+    ASSERT(code->extra_ic_state() == target()->extra_ic_state());
+    IC::set_target(code);
+  }

[Martin Maly, 2011/02/27 23:04:04]

ditto for KeyedStoreIC.

+
   // Stub accessors.
   static Code* initialize_stub() {
     return Builtins::builtin(Builtins::KeyedStoreIC_Initialize);
   }
+  static Code* initialize_stub_strict() {
+    return Builtins::builtin(Builtins::KeyedStoreIC_Initialize_Strict);
+  }
   static Code* megamorphic_stub() {
     return Builtins::builtin(Builtins::KeyedStoreIC_Generic);
   }
+  static Code* megamorphic_stub_strict() {
+    return Builtins::builtin(Builtins::KeyedStoreIC_Generic_Strict);
+  }
   static Code* generic_stub() {
     return Builtins::builtin(Builtins::KeyedStoreIC_Generic);
   }
+  static Code* generic_stub_strict() {
+    return Builtins::builtin(Builtins::KeyedStoreIC_Generic_Strict);
+  }
 
   static void Clear(Address address, Code* target);
 
   // Support for patching the map that is checked in an inlined
   // version of keyed store.
   // The address is the patch point for the IC call
   // (Assembler::kCallTargetAddressOffset before the end of
   // the call/return address).
   // The map is the new map that the inlined code should check against.
   static bool PatchInlinedStore(Address address, Object* map);
@@ skipping 89 matching lines @@
 
   Token::Value op_;
 };
 
 // Helper for TRBinaryOpIC and CompareIC.
 void PatchInlinedSmiCode(Address address);
 
 } }  // namespace v8::internal
 
 #endif  // V8_IC_H_