Add signed/unsigned 8-bit and 16-bit Representations

src/property-details.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 64 matching lines @@
   TRANSITION                = 6,
   // Only used as a marker in LookupResult.
   NONEXISTENT               = 7
 };
 
 
 class Representation {
  public:
   enum Kind {
     kNone,
-    kByte,
+    kInteger8,
+    kUInteger8,
+    kInteger16,
+    kUInteger16,
     kSmi,
     kInteger32,
     kDouble,
     kHeapObject,
     kTagged,
     kExternal,
     kNumRepresentations
   };
 
   Representation() : kind_(kNone) { }
 
   static Representation None() { return Representation(kNone); }
   static Representation Tagged() { return Representation(kTagged); }
-  static Representation Byte() { return Representation(kByte); }
+  static Representation Integer8() { return Representation(kInteger8); }
+  static Representation UInteger8() { return Representation(kUInteger8); }
+  static Representation Integer16() { return Representation(kInteger16); }
+  static Representation UInteger16() {
+    return Representation(kUInteger16);
+  }
   static Representation Smi() { return Representation(kSmi); }
   static Representation Integer32() { return Representation(kInteger32); }
   static Representation Double() { return Representation(kDouble); }
   static Representation HeapObject() { return Representation(kHeapObject); }
   static Representation External() { return Representation(kExternal); }
 
   static Representation FromKind(Kind kind) { return Representation(kind); }
 
   // TODO(rossberg): this should die eventually.
   static Representation FromType(TypeInfo info);
   static Representation FromType(Handle<Type> type);
 
   bool Equals(const Representation& other) const {
     return kind_ == other.kind_;
   }
 
   bool IsCompatibleForLoad(const Representation& other) const {
     return (IsDouble() && other.IsDouble()) ||
         (!IsDouble() && !other.IsDouble());
   }
 
   bool IsCompatibleForStore(const Representation& other) const {
     return Equals(other);
   }
 
   bool is_more_general_than(const Representation& other) const {
     ASSERT(kind_ != kExternal);
     ASSERT(other.kind_ != kExternal);
     if (IsHeapObject()) return other.IsDouble() || other.IsNone();
+    if (kind_ == kUInteger8 && other.kind_ == kInteger8) return false;
+    if (kind_ == kUInteger16 && other.kind_ == kInteger16) return false;
     return kind_ > other.kind_;
   }
 
   bool fits_into(const Representation& other) const {
     return other.is_more_general_than(*this) || other.Equals(*this);
   }
 
   Representation generalize(Representation other) {
     if (other.fits_into(*this)) return *this;
     if (other.is_more_general_than(*this)) return other;
     return Representation::Tagged();
   }
 
+  int size() const {
+    ASSERT(!IsNone());
+    if (IsInteger8() || IsUInteger8()) {
+      return sizeof(uint8_t);
+    }
+    if (IsInteger16() || IsUInteger16()) {
+      return sizeof(uint16_t);
+    }
+    if (IsInteger32()) {
+      return sizeof(uint32_t);
+    }
+    return kPointerSize;
+  }
+
   Kind kind() const { return static_cast<Kind>(kind_); }
   bool IsNone() const { return kind_ == kNone; }
-  bool IsByte() const { return kind_ == kByte; }
+  bool IsInteger8() const { return kind_ == kInteger8; }
+  bool IsUInteger8() const { return kind_ == kUInteger8; }
+  bool IsInteger16() const { return kind_ == kInteger16; }
+  bool IsUInteger16() const { return kind_ == kUInteger16; }
   bool IsTagged() const { return kind_ == kTagged; }
   bool IsSmi() const { return kind_ == kSmi; }
   bool IsSmiOrTagged() const { return IsSmi() || IsTagged(); }
   bool IsInteger32() const { return kind_ == kInteger32; }
   bool IsSmiOrInteger32() const { return IsSmi() || IsInteger32(); }
   bool IsDouble() const { return kind_ == kDouble; }
   bool IsHeapObject() const { return kind_ == kHeapObject; }
   bool IsExternal() const { return kind_ == kExternal; }
   bool IsSpecialization() const {
-    return IsByte() || IsSmi() || IsInteger32() || IsDouble();
+    return IsInteger8() || IsUInteger8() ||
+      IsInteger16() || IsUInteger16() ||
+      IsSmi() || IsInteger32() || IsDouble();
   }
   const char* Mnemonic() const;
 
  private:
   explicit Representation(Kind k) : kind_(k) { }
 
   // Make sure kind fits in int8.
   STATIC_ASSERT(kNumRepresentations <= (1 << kBitsPerByte));
 
   int8_t kind_;
@@ skipping 84 matching lines @@
   // constants can be embedded in generated code.
   class TypeField:                public BitField<PropertyType,       0,  3> {};
   class AttributesField:          public BitField<PropertyAttributes, 3,  3> {};
 
   // Bit fields for normalized objects.
   class DeletedField:             public BitField<uint32_t,           6,  1> {};
   class DictionaryStorageField:   public BitField<uint32_t,           7, 24> {};
 
   // Bit fields for fast objects.
   class DescriptorPointer:        public BitField<uint32_t,           6, 11> {};
-  class RepresentationField:      public BitField<uint32_t,          17,  3> {};
-  class FieldIndexField:          public BitField<uint32_t,          20, 11> {};
+  class RepresentationField:      public BitField<uint32_t,          17,  4> {};
+  class FieldIndexField:          public BitField<uint32_t,          21, 10> {};
 
   static const int kInitialIndex = 1;
 
  private:
   PropertyDetails(int value, int pointer) {
     value_ = DescriptorPointer::update(value, pointer);
   }
   PropertyDetails(int value, Representation representation) {
     value_ = RepresentationField::update(
         value, EncodeRepresentation(representation));
   }
   PropertyDetails(int value, PropertyAttributes attributes) {
     value_ = AttributesField::update(value, attributes);
   }
 
   uint32_t value_;
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_PROPERTY_DETAILS_H_