Stop throwing exceptions for out-of-range accesses to CanvasArrays....

src/objects.cc

 // 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 6032 matching lines @@
         return Smi::FromInt(value);
       }
       break;
     }
     case EXTERNAL_BYTE_ELEMENTS: {
       ExternalByteArray* array = ExternalByteArray::cast(elements());
       if (index < static_cast<uint32_t>(array->length())) {
         int8_t value = array->get(index);
         return Smi::FromInt(value);
       }
-      return Top::Throw(*Factory::NewIndexError(index));
+      break;
     }
     case EXTERNAL_UNSIGNED_BYTE_ELEMENTS: {
       ExternalUnsignedByteArray* array =
           ExternalUnsignedByteArray::cast(elements());
       if (index < static_cast<uint32_t>(array->length())) {
         uint8_t value = array->get(index);
         return Smi::FromInt(value);
       }
-      return Top::Throw(*Factory::NewIndexError(index));
+      break;
     }
     case EXTERNAL_SHORT_ELEMENTS: {
       ExternalShortArray* array = ExternalShortArray::cast(elements());
       if (index < static_cast<uint32_t>(array->length())) {
         int16_t value = array->get(index);
         return Smi::FromInt(value);
       }
-      return Top::Throw(*Factory::NewIndexError(index));
+      break;
     }
     case EXTERNAL_UNSIGNED_SHORT_ELEMENTS: {
       ExternalUnsignedShortArray* array =
           ExternalUnsignedShortArray::cast(elements());
       if (index < static_cast<uint32_t>(array->length())) {
         uint16_t value = array->get(index);
         return Smi::FromInt(value);
       }
-      return Top::Throw(*Factory::NewIndexError(index));
+      break;
     }
     case EXTERNAL_INT_ELEMENTS: {
       ExternalIntArray* array = ExternalIntArray::cast(elements());
       if (index < static_cast<uint32_t>(array->length())) {
         int32_t value = array->get(index);
         return Heap::NumberFromInt32(value);
       }
-      return Top::Throw(*Factory::NewIndexError(index));
+      break;
     }
     case EXTERNAL_UNSIGNED_INT_ELEMENTS: {
       ExternalUnsignedIntArray* array =
           ExternalUnsignedIntArray::cast(elements());
       if (index < static_cast<uint32_t>(array->length())) {
         uint32_t value = array->get(index);
         return Heap::NumberFromUint32(value);
       }
-      return Top::Throw(*Factory::NewIndexError(index));
+      break;
     }
     case EXTERNAL_FLOAT_ELEMENTS: {
       ExternalFloatArray* array = ExternalFloatArray::cast(elements());
       if (index < static_cast<uint32_t>(array->length())) {
         float value = array->get(index);
         return Heap::AllocateHeapNumber(value);
       }
-      return Top::Throw(*Factory::NewIndexError(index));
+      break;
     }
     case DICTIONARY_ELEMENTS: {
       NumberDictionary* dictionary = element_dictionary();
       int entry = dictionary->FindEntry(index);
       if (entry != NumberDictionary::kNotFound) {
         Object* element = dictionary->ValueAt(entry);
         PropertyDetails details = dictionary->DetailsAt(entry);
         if (details.type() == CALLBACKS) {
           // Only accessors allowed as elements.
           FixedArray* structure = FixedArray::cast(element);
@@ skipping 1198 matching lines @@
       cast_value = static_cast<ValueType>(int_value);
     } else if (value->IsHeapNumber()) {
       double double_value = HeapNumber::cast(value)->value();
       cast_value = static_cast<ValueType>(DoubleToInt32(double_value));
     } else {
       // Clamp undefined to zero (default). All other types have been
       // converted to a number type further up in the call chain.
       ASSERT(value->IsUndefined());
     }
     receiver->set(index, cast_value);
-  } else {
-    return Top::Throw(*Factory::NewIndexError(index));
   }
   return Heap::NumberFromInt32(cast_value);
 }
 
 
 Object* ExternalByteArray::SetValue(uint32_t index, Object* value) {
   return ExternalArrayIntSetter<ExternalByteArray, int8_t>
       (this, index, value);
 }
 
@@ skipping 30 matching lines @@
       cast_value = static_cast<uint32_t>(int_value);
     } else if (value->IsHeapNumber()) {
       double double_value = HeapNumber::cast(value)->value();
       cast_value = static_cast<uint32_t>(DoubleToUint32(double_value));
     } else {
       // Clamp undefined to zero (default). All other types have been
       // converted to a number type further up in the call chain.
       ASSERT(value->IsUndefined());
     }
     set(index, cast_value);
-  } else {
-    return Top::Throw(*Factory::NewIndexError(index));
   }
   return Heap::NumberFromUint32(cast_value);
 }
 
 
 Object* ExternalFloatArray::SetValue(uint32_t index, Object* value) {
   float cast_value = 0;
   if (index < static_cast<uint32_t>(length())) {
     if (value->IsSmi()) {
       int int_value = Smi::cast(value)->value();
       cast_value = static_cast<float>(int_value);
     } else if (value->IsHeapNumber()) {
       double double_value = HeapNumber::cast(value)->value();
       cast_value = static_cast<float>(double_value);
     } else {
       // Clamp undefined to zero (default). All other types have been
       // converted to a number type further up in the call chain.
       ASSERT(value->IsUndefined());
     }
     set(index, cast_value);
-  } else {
-    return Top::Throw(*Factory::NewIndexError(index));
   }
   return Heap::AllocateHeapNumber(cast_value);
 }
 
 
 Object* GlobalObject::GetPropertyCell(LookupResult* result) {
   ASSERT(!HasFastProperties());
   Object* value = property_dictionary()->ValueAt(result->GetDictionaryEntry());
   ASSERT(value->IsJSGlobalPropertyCell());
   return value;
@@ skipping 903 matching lines @@
   if (break_point_objects()->IsUndefined()) return 0;
   // Single beak point.
   if (!break_point_objects()->IsFixedArray()) return 1;
   // Multiple break points.
   return FixedArray::cast(break_point_objects())->length();
 }
 #endif
 
 
 } }  // namespace v8::internal