In-heap small typed arrays

src/objects-inl.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 1703 matching lines @@
 
 void JSObject::initialize_elements() {
   if (map()->has_fast_smi_or_object_elements() ||
       map()->has_fast_double_elements()) {
     ASSERT(!GetHeap()->InNewSpace(GetHeap()->empty_fixed_array()));
     WRITE_FIELD(this, kElementsOffset, GetHeap()->empty_fixed_array());
   } else if (map()->has_external_array_elements()) {
     ExternalArray* empty_array = GetHeap()->EmptyExternalArrayForMap(map());
     ASSERT(!GetHeap()->InNewSpace(empty_array));
     WRITE_FIELD(this, kElementsOffset, empty_array);
+  } else if (map()->has_fixed_typed_array_elements()) {
+    FixedTypedArrayBase* empty_array =
+      GetHeap()->EmptyFixedTypedArrayForMap(map());
+    ASSERT(!GetHeap()->InNewSpace(empty_array));
+    WRITE_FIELD(this, kElementsOffset, empty_array);
   } else {
     UNREACHABLE();
   }
 }
 
 
 MaybeObject* JSObject::ResetElements() {
   if (map()->is_observed()) {
     // Maintain invariant that observed elements are always in dictionary mode.
     SeededNumberDictionary* dictionary;
@@ skipping 1891 matching lines @@
 }
 
 
 void ExternalFloat64Array::set(int index, double value) {
   ASSERT((index >= 0) && (index < this->length()));
   double* ptr = static_cast<double*>(external_pointer());
   ptr[index] = value;
 }
 
 
+void* FixedTypedArrayBase::DataPtr() {
+  return FIELD_ADDR(this, kDataOffset);
+}
+
+
+int FixedTypedArrayBase::DataSize() {
+  InstanceType instance_type = map()->instance_type();
+  int element_size;
+  switch (instance_type) {
+#define TYPED_ARRAY_CASE(Type, type, TYPE, ctype, size)                       \
+    case FIXED_##TYPE##_ARRAY_TYPE:                                           \
+      element_size = size;                                                    \
+      break;
+
+    TYPED_ARRAYS(TYPED_ARRAY_CASE)
+#undef TYPED_ARRAY_CASE
+    default:
+      UNREACHABLE();
+      return 0;
+  }
+  return length() * element_size;
+}
+
+
 int FixedTypedArrayBase::size() {
-  InstanceType instance_type = map()->instance_type();
-  int element_size;
-  switch (instance_type) {
-    case FIXED_UINT8_ARRAY_TYPE:
-    case FIXED_INT8_ARRAY_TYPE:
-    case FIXED_UINT8_CLAMPED_ARRAY_TYPE:
-      element_size = 1;
-      break;
-    case FIXED_UINT16_ARRAY_TYPE:
-    case FIXED_INT16_ARRAY_TYPE:
-      element_size = 2;
-      break;
-    case FIXED_UINT32_ARRAY_TYPE:
-    case FIXED_INT32_ARRAY_TYPE:
-    case FIXED_FLOAT32_ARRAY_TYPE:
-      element_size = 4;
-      break;
-    case FIXED_FLOAT64_ARRAY_TYPE:
-      element_size = 8;
-      break;
-    default:
-      UNREACHABLE();
-      return 0;
-  }
-  return OBJECT_POINTER_ALIGN(kDataOffset + length() * element_size);
+  return OBJECT_POINTER_ALIGN(kDataOffset + DataSize());
 }
 
 
+uint8_t Uint8ArrayTraits::defaultValue() { return 0; }
+
+
+uint8_t Uint8ClampedArrayTraits::defaultValue() { return 0; }
+
+
+int8_t Int8ArrayTraits::defaultValue() { return 0; }
+
+
+uint16_t Uint16ArrayTraits::defaultValue() { return 0; }
+
+
+int16_t Int16ArrayTraits::defaultValue() { return 0; }
+
+
+uint32_t Uint32ArrayTraits::defaultValue() { return 0; }
+
+
+int32_t Int32ArrayTraits::defaultValue() { return 0; }
+
+
+float Float32ArrayTraits::defaultValue() {
+  return static_cast<double>(OS::nan_value());
+}
+
+
+double Float64ArrayTraits::defaultValue() { return OS::nan_value(); }
+
+
 template <class Traits>
 typename Traits::ElementType FixedTypedArray<Traits>::get_scalar(int index) {
   ASSERT((index >= 0) && (index < this->length()));
   ElementType* ptr = reinterpret_cast<ElementType*>(
       FIELD_ADDR(this, kDataOffset));
   return ptr[index];
 }
 
 
 template<> inline
@@ skipping 15 matching lines @@
 
 template<> inline
 void FixedTypedArray<Float64ArrayTraits>::set(
     int index, Float64ArrayTraits::ElementType value) {
   ASSERT((index >= 0) && (index < this->length()));
   WRITE_DOUBLE_FIELD(this, ElementOffset(index), value);
 }
 
 
 template <class Traits>
+typename Traits::ElementType FixedTypedArray<Traits>::from_int(int value) {
+  return static_cast<ElementType>(value);
+}
+
+
+template <> inline
+uint8_t FixedTypedArray<Uint8ClampedArrayTraits>::from_int(int value) {
+  if (value < 0) return 0;
+  if (value > 0xFF) return 0xFF;
+  return static_cast<uint8_t>(value);
+}
+
+
+template <class Traits>
+typename Traits::ElementType FixedTypedArray<Traits>::from_double(
+    double value) {
+  return static_cast<ElementType>(DoubleToInt32(value));
+}
+
+
+template<> inline
+uint8_t FixedTypedArray<Uint8ClampedArrayTraits>::from_double(double value) {
+  if (value < 0) return 0;
+  if (value > 0xFF) return 0xFF;
+  return static_cast<uint8_t>(lrint(value));
+}
+
+
+template<> inline
+float FixedTypedArray<Float32ArrayTraits>::from_double(double value) {
+  return static_cast<float>(value);
+}
+
+
+template<> inline
+double FixedTypedArray<Float64ArrayTraits>::from_double(double value) {
+  return value;
+}
+
+
+template <class Traits>
 MaybeObject* FixedTypedArray<Traits>::get(int index) {
   return Traits::ToObject(GetHeap(), get_scalar(index));
 }
 
 template <class Traits>
 MaybeObject* FixedTypedArray<Traits>::SetValue(uint32_t index, Object* value) {
   ElementType cast_value = Traits::defaultValue();
   if (index < static_cast<uint32_t>(length())) {
     if (value->IsSmi()) {
       int int_value = Smi::cast(value)->value();
-      cast_value = static_cast<ElementType>(int_value);
+      cast_value = from_int(int_value);
     } else if (value->IsHeapNumber()) {
       double double_value = HeapNumber::cast(value)->value();
-      cast_value = static_cast<ElementType>(DoubleToInt32(double_value));
+      cast_value = from_double(double_value);
     } else {
       // Clamp undefined to the default value. All other types have been
       // converted to a number type further up in the call chain.
       ASSERT(value->IsUndefined());
     }
     set(index, cast_value);
   }
   return Traits::ToObject(GetHeap(), cast_value);
 }
 
@@ skipping 2260 matching lines @@
 #undef EXTERNAL_ELEMENTS_CHECK
 
 
 bool JSObject::HasFixedTypedArrayElements() {
   HeapObject* array = elements();
   ASSERT(array != NULL);
   return array->IsFixedTypedArrayBase();
 }
 
 
+#define FIXED_TYPED_ELEMENTS_CHECK(Type, type, TYPE, ctype, size)         \
+bool JSObject::HasFixed##Type##Elements() {                               \
+  HeapObject* array = elements();                                         \
+  ASSERT(array != NULL);                                                  \
+  if (!array->IsHeapObject())                                             \
+    return false;                                                         \
+  return array->map()->instance_type() == FIXED_##TYPE##_ARRAY_TYPE;      \
+}
+
+TYPED_ARRAYS(FIXED_TYPED_ELEMENTS_CHECK)
+
+#undef FIXED_TYPED_ELEMENTS_CHECK
+
+
 bool JSObject::HasNamedInterceptor() {
   return map()->has_named_interceptor();
 }
 
 
 bool JSObject::HasIndexedInterceptor() {
   return map()->has_indexed_interceptor();
 }
 
 
@@ skipping 750 matching lines @@
 #undef READ_UINT32_FIELD
 #undef WRITE_UINT32_FIELD
 #undef READ_SHORT_FIELD
 #undef WRITE_SHORT_FIELD
 #undef READ_BYTE_FIELD
 #undef WRITE_BYTE_FIELD
 
 } }  // namespace v8::internal
 
 #endif  // V8_OBJECTS_INL_H_