(early draft) Strict mode - throw exception on assignment to read only property.

src/ic.cc

Index: src/ic.cc
diff --git a/src/ic.cc b/src/ic.cc
index 7482830ae0bdf990cb8acecaa93b0efb59eb70b9..6d00d14e82086ea9ff8a5823d487d6eb8002b022 100644
--- a/src/ic.cc
+++ b/src/ic.cc
@@ -343,7 +343,7 @@ void StoreIC::Clear(Address address, Code* target) {
   if (target->ic_state() == UNINITIALIZED) return;
   ClearInlinedVersion(address);
   SetTargetAtAddress(address,
-      target->extra_ic_state() == kStoreICStrict
+      target->extra_ic_state() == kStrictMode
         ? initialize_stub_strict()
         : initialize_stub());
 }
@@ -366,7 +366,10 @@ void KeyedStoreIC::RestoreInlinedVersion(Address address) {
 
 void KeyedStoreIC::Clear(Address address, Code* target) {
   if (target->ic_state() == UNINITIALIZED) return;
-  SetTargetAtAddress(address, initialize_stub());
+  SetTargetAtAddress(address,
+      target->extra_ic_state() == kStrictMode
+        ? initialize_stub_strict()
+        : initialize_stub());
 }
 
 
@@ -1226,7 +1229,8 @@ MaybeObject* KeyedLoadIC::Load(State state,
         if (receiver->HasExternalArrayElements()) {
           MaybeObject* probe =
               StubCache::ComputeKeyedLoadOrStoreExternalArray(*receiver,
-                                                              false);
+                                                              false,
+                                                              kNonStrictMode);
           stub = probe->IsFailure() ?
               NULL : Code::cast(probe->ToObjectUnchecked());
         } else if (receiver->HasIndexedInterceptor()) {
@@ -1412,11 +1416,12 @@ MaybeObject* StoreIC::Store(State state,
 #ifdef DEBUG
     if (FLAG_trace_ic) PrintF("[StoreIC : +#length /array]\n");
 #endif
-    Builtins::Name target = (extra_ic_state == kStoreICStrict)
+    Builtins::Name target = (extra_ic_state == kStrictMode)
         ? Builtins::StoreIC_ArrayLength_Strict
         : Builtins::StoreIC_ArrayLength;
     set_target(Builtins::builtin(target));
-    return receiver->SetProperty(*name, *value, NONE);
+    return receiver->SetProperty(*name, *value, NONE,
+                                 static_cast<StrictModeFlag>(extra_ic_state));
   }
 
   // Lookup the property locally in the receiver.
@@ -1446,7 +1451,9 @@ MaybeObject* StoreIC::Store(State state,
               PrintF("[StoreIC : inline patch %s]\n", *name->ToCString());
             }
 #endif
-            return receiver->SetProperty(*name, *value, NONE);
+            return receiver->SetProperty(
+                *name, *value, NONE,
+                static_cast<StrictModeFlag>(extra_ic_state));
 #ifdef DEBUG
 
           } else {
@@ -1476,8 +1483,12 @@ MaybeObject* StoreIC::Store(State state,
       UpdateCaches(&lookup, state, extra_ic_state, receiver, name, value);
     } else {
       // Strict mode doesn't allow setting non-existent global property.
-      if (extra_ic_state == kStoreICStrict && IsContextual(object)) {
-        return ReferenceError("not_defined", name);
+      if (extra_ic_state == kStrictMode) {
+        if (lookup.IsFound() && lookup.IsReadOnly()) {
+          return TypeError("strict_rdonly_property", object, name);
+        } else if (IsContextual(object)) {
+          return ReferenceError("not_defined", name);
+        }
       }
     }
   }
@@ -1485,7 +1496,7 @@ MaybeObject* StoreIC::Store(State state,
   if (receiver->IsJSGlobalProxy()) {
     // Generate a generic stub that goes to the runtime when we see a global
     // proxy as receiver.
-    Code* stub = (extra_ic_state == kStoreICStrict)
+    Code* stub = (extra_ic_state == kStrictMode)
         ? global_proxy_stub_strict()
         : global_proxy_stub();
     if (target() != stub) {
@@ -1497,7 +1508,8 @@ MaybeObject* StoreIC::Store(State state,
   }
 
   // Set the property.
-  return receiver->SetProperty(*name, *value, NONE);
+  return receiver->SetProperty(*name, *value, NONE,
+                               static_cast<StrictModeFlag>(extra_ic_state));
 }
 
 
@@ -1582,7 +1594,7 @@ void StoreIC::UpdateCaches(LookupResult* lookup,
   } else if (state == MONOMORPHIC) {
     // Only move to megamorphic if the target changes.
     if (target() != Code::cast(code)) {
-      set_target(extra_ic_state == kStoreICStrict
+      set_target(extra_ic_state == kStrictMode
                    ? megamorphic_stub_strict()
                    : megamorphic_stub());
     }
@@ -1598,6 +1610,7 @@ void StoreIC::UpdateCaches(LookupResult* lookup,
 
 
 MaybeObject* KeyedStoreIC::Store(State state,
+                                 Code::ExtraICState extra_ic_state,
                                  Handle<Object> object,
                                  Handle<Object> key,
                                  Handle<Object> value) {
@@ -1633,7 +1646,8 @@ MaybeObject* KeyedStoreIC::Store(State state,
     }
 
     // Set the property.
-    return receiver->SetProperty(*name, *value, NONE);
+    return receiver->SetProperty(*name, *value, NONE,
+                                 static_cast<StrictModeFlag>(extra_ic_state));
   }
 
   // Do not use ICs for objects that require access checks (including
@@ -1642,13 +1656,18 @@ MaybeObject* KeyedStoreIC::Store(State state,
   ASSERT(!(use_ic && object->IsJSGlobalProxy()));
 
   if (use_ic) {
-    Code* stub = generic_stub();
+    Code* stub = extra_ic_state == kStrictMode
+        ? generic_stub_strict()
+        : generic_stub();
+    // TODO(mmaly): Fix IC specialization to take strict mode into account.
+    // Currently they jump to KeyedStoreIC_Miss which is non-strict.
     if (state == UNINITIALIZED) {
       if (object->IsJSObject()) {
         Handle<JSObject> receiver = Handle<JSObject>::cast(object);
         if (receiver->HasExternalArrayElements()) {
           MaybeObject* probe =
-              StubCache::ComputeKeyedLoadOrStoreExternalArray(*receiver, true);
+              StubCache::ComputeKeyedLoadOrStoreExternalArray(
+                  *receiver, true, extra_ic_state);
           stub = probe->IsFailure() ?
               NULL : Code::cast(probe->ToObjectUnchecked());
         } else if (receiver->HasPixelElements()) {
@@ -1668,7 +1687,9 @@ MaybeObject* KeyedStoreIC::Store(State state,
   }
 
   // Set the property.
-  return Runtime::SetObjectProperty(object, key, value, NONE);
+  ASSERT(extra_ic_state == kStrictMode || extra_ic_state == kNonStrictMode);
+  return Runtime::SetObjectProperty(
+      object, key, value, NONE, static_cast<StrictModeFlag>(extra_ic_state));
 }
 
 
@@ -1900,8 +1921,10 @@ MUST_USE_RESULT MaybeObject* KeyedStoreIC_Miss(Arguments args) {
   ASSERT(args.length() == 3);
   KeyedStoreIC ic;
   IC::State state = IC::StateFrom(ic.target(), args[0], args[1]);
-  return ic.Store(state, args.at<Object>(0), args.at<Object>(1),
-                  args.at<Object>(2));
+  Code::ExtraICState extra_ic_state = ic.target()->extra_ic_state();
+  // TODO(mmaly): Validate extra_ic_state here and pass StrictModeFlag directly.
+  return ic.Store(state, extra_ic_state, args.at<Object>(0),
+                  args.at<Object>(1), args.at<Object>(2));
 }