Remaining changes to fully support FastDoubleArray.

src/objects.cc

 // 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 4671 matching lines @@
   return cache;
 }
 
 
 MaybeObject* FixedArray::AddKeysFromJSArray(JSArray* array) {
   ASSERT(!array->HasExternalArrayElements());
   switch (array->GetElementsKind()) {
     case JSObject::FAST_ELEMENTS:
       return UnionOfKeys(FixedArray::cast(array->elements()));
     case JSObject::FAST_DOUBLE_ELEMENTS:
-      UNIMPLEMENTED();
+      return UnionOfDoubleKeys(FixedDoubleArray::cast(array->elements()));
       break;
     case JSObject::DICTIONARY_ELEMENTS: {
       NumberDictionary* dict = array->element_dictionary();
       int size = dict->NumberOfElements();
 
       // Allocate a temporary fixed array.
       Object* object;
       { MaybeObject* maybe_object = GetHeap()->AllocateFixedArray(size);
         if (!maybe_object->ToObject(&object)) return maybe_object;
       }
@@ skipping 76 matching lines @@
       ASSERT(e->IsString() || e->IsNumber());
       result->set(len0 + index, e, mode);
       index++;
     }
   }
   ASSERT(extra == index);
   return result;
 }
 
 
+MaybeObject* FixedArray::UnionOfDoubleKeys(FixedDoubleArray* other) {
+  int len0 = length();
+#ifdef DEBUG
+  if (FLAG_enable_slow_asserts) {
+    for (int i = 0; i < len0; i++) {
+      ASSERT(get(i)->IsString() || get(i)->IsNumber());
+    }
+  }
+#endif
+  int len1 = other->length();
+  // Optimize if 'other' is empty.
+  // We cannot optimize if 'this' is empty, as other may have holes
+  // or non keys.
+  if (len1 == 0) return this;
+
+  // Compute how many elements are not in this.
+  int extra = 0;
+  Heap* heap = GetHeap();
+  Object* obj;
+  for (int y = 0; y < len1; y++) {
+    if (!other->is_the_hole(y)) {
+      MaybeObject* maybe_obj = heap->NumberFromDouble(other->get(y));

[Mads Ager (chromium), 2011/07/22 08:29:20]

This is nasty. This can lead to out-of-memory crashes when we are in fact not
out of memory if the double array is large enough. That is probably very
unlikely to happen, but still. I wonder if we can restrict the API so that we
can never get doubles in key arrays (require integers and strings only)?
Alternatively, we should be able to create the key integer/string directly from
the double without going through a heap number allocation.

Feel free to deal with this in a separate changelist.

[danno, 2011/07/22 09:10:12]

Submitted as 1567.
On 2011/07/22 08:29:20, Mads Ager wrote:

+      if (!maybe_obj->ToObject(&obj)) return maybe_obj;
+      if (!HasKey(this, obj)) extra++;
+    }
+  }
+
+  if (extra == 0) return this;
+
+  // Allocate the result
+  { MaybeObject* maybe_obj = GetHeap()->AllocateFixedArray(len0 + extra);
+    if (!maybe_obj->ToObject(&obj)) return maybe_obj;
+  }
+  // Fill in the content
+  AssertNoAllocation no_gc;

[Mads Ager (chromium), 2011/07/22 08:29:20]

Maybe we should change the name to AssertNoGC at some point. There will be lots
of allocation below. Maybe limit the scope of the AssertNoAllocation? This is to
make sure that the write barrier mode stays valid, right?

[danno, 2011/07/22 09:10:12]

Done.

+  FixedArray* result = FixedArray::cast(obj);
+  WriteBarrierMode mode = result->GetWriteBarrierMode(no_gc);
+  for (int i = 0; i < len0; i++) {
+    Object* e = get(i);
+    ASSERT(e->IsString() || e->IsNumber());
+    result->set(i, e, mode);
+  }
+  // Fill in the extra keys.
+  int index = 0;
+  for (int y = 0; y < len1; y++) {
+    if (!other->is_the_hole(y)) {
+      MaybeObject* maybe_obj = heap->NumberFromDouble(other->get(y));

[Mads Ager (chromium), 2011/07/22 08:29:20]

Here again. So we actually allocate two new heap numbers per entry. We should
create the integer/string key directly from the double.

[danno, 2011/07/22 09:10:12]

See above.

+      if (!maybe_obj->ToObject(&obj)) return maybe_obj;
+      if (!HasKey(this, obj)) {
+        result->set(len0 + index, obj);
+        index++;
+      }
+    }
+  }
+  ASSERT(extra == index);
+  return result;
+}
+
+
 MaybeObject* FixedArray::CopySize(int new_length) {
   Heap* heap = GetHeap();
   if (new_length == 0) return heap->empty_fixed_array();
   Object* obj;
   { MaybeObject* maybe_obj = heap->AllocateFixedArray(new_length);
     if (!maybe_obj->ToObject(&obj)) return maybe_obj;
   }
   FixedArray* result = FixedArray::cast(obj);
   // Copy the content
   AssertNoAllocation no_gc;
@@ skipping 2735 matching lines @@
 
 
 MaybeObject* JSObject::SetSlowElements(Object* len) {
   // We should never end in here with a pixel or external array.
   ASSERT(!HasExternalArrayElements());
 
   uint32_t new_length = static_cast<uint32_t>(len->Number());
 
   switch (GetElementsKind()) {
     case FAST_ELEMENTS: {
+    case FAST_DOUBLE_ELEMENTS:
       // Make sure we never try to shrink dense arrays into sparse arrays.
-      ASSERT(static_cast<uint32_t>(FixedArray::cast(elements())->length()) <=
-                                   new_length);
+      ASSERT(static_cast<uint32_t>(
+          FixedArrayBase::cast(elements())->length()) <= new_length);
       MaybeObject* result = NormalizeElements();
       if (result->IsFailure()) return result;
 
       // Update length for JSArrays.
       if (IsJSArray()) JSArray::cast(this)->set_length(len);
       break;
     }
     case DICTIONARY_ELEMENTS: {
       if (IsJSArray()) {
         uint32_t old_length =
             static_cast<uint32_t>(JSArray::cast(this)->length()->Number());
         element_dictionary()->RemoveNumberEntries(new_length, old_length),
         JSArray::cast(this)->set_length(len);
       }
       break;
     }
     case NON_STRICT_ARGUMENTS_ELEMENTS:
       UNIMPLEMENTED();
       break;
     case EXTERNAL_BYTE_ELEMENTS:
     case EXTERNAL_UNSIGNED_BYTE_ELEMENTS:
     case EXTERNAL_SHORT_ELEMENTS:
     case EXTERNAL_UNSIGNED_SHORT_ELEMENTS:
     case EXTERNAL_INT_ELEMENTS:
     case EXTERNAL_UNSIGNED_INT_ELEMENTS:
     case EXTERNAL_FLOAT_ELEMENTS:
     case EXTERNAL_DOUBLE_ELEMENTS:
     case EXTERNAL_PIXEL_ELEMENTS:
-    case FAST_DOUBLE_ELEMENTS:
       UNREACHABLE();
       break;
   }
   return this;
 }
 
 
 MaybeObject* JSArray::Initialize(int capacity) {
   Heap* heap = GetHeap();
   ASSERT(capacity >= 0);
@@ skipping 321 matching lines @@
       uint32_t length = IsJSArray() ?
           static_cast<uint32_t>
               (Smi::cast(JSArray::cast(this)->length())->value()) :
           static_cast<uint32_t>(FixedArray::cast(elements())->length());
       if ((index < length) &&
           !FixedArray::cast(elements())->get(index)->IsTheHole()) {
         return true;
       }
       break;
     }
+    case FAST_DOUBLE_ELEMENTS: {
+      uint32_t length = IsJSArray() ?
+          static_cast<uint32_t>
+              (Smi::cast(JSArray::cast(this)->length())->value()) :
+          static_cast<uint32_t>(FixedDoubleArray::cast(elements())->length());
+      if ((index < length) &&
+          !FixedDoubleArray::cast(elements())->is_the_hole(index)) {
+        return true;
+      }
+      break;
+    }
     case EXTERNAL_PIXEL_ELEMENTS: {
       ExternalPixelArray* pixels = ExternalPixelArray::cast(elements());
       if (index < static_cast<uint32_t>(pixels->length())) {
         return true;
       }
       break;
     }
     case EXTERNAL_BYTE_ELEMENTS:
     case EXTERNAL_UNSIGNED_BYTE_ELEMENTS:
     case EXTERNAL_SHORT_ELEMENTS:
     case EXTERNAL_UNSIGNED_SHORT_ELEMENTS:
     case EXTERNAL_INT_ELEMENTS:
     case EXTERNAL_UNSIGNED_INT_ELEMENTS:
     case EXTERNAL_FLOAT_ELEMENTS:
-    case EXTERNAL_DOUBLE_ELEMENTS:
-    case FAST_DOUBLE_ELEMENTS: {
+    case EXTERNAL_DOUBLE_ELEMENTS: {
       ExternalArray* array = ExternalArray::cast(elements());
       if (index < static_cast<uint32_t>(array->length())) {
         return true;
       }
       break;
     }
     case DICTIONARY_ELEMENTS: {
       if (element_dictionary()->FindEntry(index)
           != NumberDictionary::kNotFound) {
         return true;
@@ skipping 1431 matching lines @@
 
   switch (GetElementsKind()) {
     case FAST_ELEMENTS: {
       uint32_t length = IsJSArray() ?
           static_cast<uint32_t>(
               Smi::cast(JSArray::cast(this)->length())->value()) :
           static_cast<uint32_t>(FixedArray::cast(elements())->length());
       return (index < length) &&
           !FixedArray::cast(elements())->get(index)->IsTheHole();
     }
+    case FAST_DOUBLE_ELEMENTS: {
+      uint32_t length = IsJSArray() ?
+          static_cast<uint32_t>(
+              Smi::cast(JSArray::cast(this)->length())->value()) :
+          static_cast<uint32_t>(FixedDoubleArray::cast(elements())->length());
+      return (index < length) &&
+          !FixedDoubleArray::cast(elements())->is_the_hole(index);
+      break;
+    }
     case EXTERNAL_PIXEL_ELEMENTS: {
       ExternalPixelArray* pixels = ExternalPixelArray::cast(elements());
       return index < static_cast<uint32_t>(pixels->length());
     }
     case EXTERNAL_BYTE_ELEMENTS:
     case EXTERNAL_UNSIGNED_BYTE_ELEMENTS:
     case EXTERNAL_SHORT_ELEMENTS:
     case EXTERNAL_UNSIGNED_SHORT_ELEMENTS:
     case EXTERNAL_INT_ELEMENTS:
     case EXTERNAL_UNSIGNED_INT_ELEMENTS:
     case EXTERNAL_FLOAT_ELEMENTS:
     case EXTERNAL_DOUBLE_ELEMENTS: {
       ExternalArray* array = ExternalArray::cast(elements());
       return index < static_cast<uint32_t>(array->length());
     }
-    case FAST_DOUBLE_ELEMENTS:
-      UNREACHABLE();
-      break;
     case DICTIONARY_ELEMENTS: {
       return element_dictionary()->FindEntry(index)
           != NumberDictionary::kNotFound;
     }
     case NON_STRICT_ARGUMENTS_ELEMENTS:
       UNIMPLEMENTED();
       break;
   }
   // All possibilities have been handled above already.
   UNREACHABLE();
@@ skipping 2434 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