Delete unused TypeInfo class

src/type-info.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 20 matching lines @@
 #include "allocation.h"
 #include "globals.h"
 #include "types.h"
 #include "zone-inl.h"
 
 namespace v8 {
 namespace internal {
 
 const int kMaxKeyedPolymorphism = 4;
 
-//         Unknown
-//           |   \____________
-//           |                |
-//      Primitive       Non-primitive
-//           |   \_______     |
-//           |           |    |
-//        Number       String |
-//         /   \         |    |
-//    Double  Integer32  |   /
-//        |      |      /   /
-//        |     Smi    /   /
-//        |      |    / __/
-//        Uninitialized.
 
-class TypeInfo {
- public:
-  TypeInfo() : type_(kUninitialized) { }
-
-  static TypeInfo Unknown() { return TypeInfo(kUnknown); }
-  // We know it's a primitive type.
-  static TypeInfo Primitive() { return TypeInfo(kPrimitive); }
-  // We know it's a number of some sort.
-  static TypeInfo Number() { return TypeInfo(kNumber); }
-  // We know it's a signed 32 bit integer.
-  static TypeInfo Integer32() { return TypeInfo(kInteger32); }
-  // We know it's a Smi.
-  static TypeInfo Smi() { return TypeInfo(kSmi); }
-  // We know it's a heap number.
-  static TypeInfo Double() { return TypeInfo(kDouble); }
-  // We know it's a string.
-  static TypeInfo String() { return TypeInfo(kString); }
-  // We know it's an internalized string.
-  static TypeInfo InternalizedString() { return TypeInfo(kInternalizedString); }
-  // We know it's a non-primitive (object) type.
-  static TypeInfo NonPrimitive() { return TypeInfo(kNonPrimitive); }
-  // We haven't started collecting info yet.
-  static TypeInfo Uninitialized() { return TypeInfo(kUninitialized); }
-
-  int ToInt() {
-    return type_;
+// Integer32 is an integer that can be represented as a signed 32-bit
+// integer. It has to be in the range [-2^31, 2^31 - 1].
+// We also have to check for negative 0 as it is not an Integer32.
+static inline bool IsInt32Double(double value) {

[rossberg, 2013/12/16 09:21:13]

We might consider moving this elsewhere, since it isn't really about "type
info". Maybe v8conversions.h?

[Sven Panne, 2013/12/16 09:50:40]

... and perhaps refactor it to:

----------------------------------------
inline bool IsMinusZero(double value) {
  return DoubleRepresentation(value).bits == DoubleRepresentation(-0.0).bits;
}

static inline bool IsInt32Double(double value) {
  return !IsMinusZero(value) &&
      kMinInt <= value && value <= kMaxInt &&
      value == static_cast<int32_t>(value);
}
----------------------------------------

For added bonus points, use IsMinusZero at half a dozen similar places, add
operator=() to DoubleRepresentation, use IsInt32Double at several places,
perhaps add an IsInRange predicate. :-)

[Jakob Kummerow, 2013/12/17 16:38:48]

Done.

[Jakob Kummerow, 2013/12/17 16:38:48]

Done.
Done.
Disagreed. DoubleRepresentation is a union; equality comparison semantics are
caller dependent, so having a default behavior by means of an operator=() would
just be confusing.
Done.
Unrelated.

[Sven Panne, 2013/12/18 07:05:11]

Nope, it would exactly be the right thing: The whole point of 
DoubleRepresentation is (surprise) a way to fiddle around with the
representation of doubles. So operator=() is extremely well-defined, namely
equality on the representation.

+  const DoubleRepresentation minus_zero(-0.0);
+  DoubleRepresentation rep(value);
+  if (rep.bits == minus_zero.bits) return false;
+  if (value >= kMinInt && value <= kMaxInt &&
+      value == static_cast<int32_t>(value)) {
+    return true;
   }
-
-  static TypeInfo FromInt(int bit_representation) {
-    Type t = static_cast<Type>(bit_representation);
-    ASSERT(t == kUnknown ||
-           t == kPrimitive ||
-           t == kNumber ||
-           t == kInteger32 ||
-           t == kSmi ||
-           t == kDouble ||
-           t == kString ||
-           t == kNonPrimitive);
-    return TypeInfo(t);
-  }
-
-  // Return the weakest (least precise) common type.
-  static TypeInfo Combine(TypeInfo a, TypeInfo b) {
-    return TypeInfo(static_cast<Type>(a.type_ & b.type_));
-  }
-
-
-  // Integer32 is an integer that can be represented as a signed
-  // 32-bit integer. It has to be
-  // in the range [-2^31, 2^31 - 1]. We also have to check for negative 0
-  // as it is not an Integer32.
-  static inline bool IsInt32Double(double value) {
-    const DoubleRepresentation minus_zero(-0.0);
-    DoubleRepresentation rep(value);
-    if (rep.bits == minus_zero.bits) return false;
-    if (value >= kMinInt && value <= kMaxInt &&
-        value == static_cast<int32_t>(value)) {
-      return true;
-    }
-    return false;
-  }
-
-  static TypeInfo FromValue(Handle<Object> value);
-
-  bool Equals(const TypeInfo& other) {
-    return type_ == other.type_;
-  }
-
-  inline bool IsUnknown() {
-    ASSERT(type_ != kUninitialized);
-    return type_ == kUnknown;
-  }
-
-  inline bool IsPrimitive() {
-    ASSERT(type_ != kUninitialized);
-    return ((type_ & kPrimitive) == kPrimitive);
-  }
-
-  inline bool IsNumber() {
-    ASSERT(type_ != kUninitialized);
-    return ((type_ & kNumber) == kNumber);
-  }
-
-  inline bool IsSmi() {
-    ASSERT(type_ != kUninitialized);
-    return ((type_ & kSmi) == kSmi);
-  }
-
-  inline bool IsInternalizedString() {
-    ASSERT(type_ != kUninitialized);
-    return ((type_ & kInternalizedString) == kInternalizedString);
-  }
-
-  inline bool IsNonInternalizedString() {
-    ASSERT(type_ != kUninitialized);
-    return ((type_ & kInternalizedString) == kString);
-  }
-
-  inline bool IsInteger32() {
-    ASSERT(type_ != kUninitialized);
-    return ((type_ & kInteger32) == kInteger32);
-  }
-
-  inline bool IsDouble() {
-    ASSERT(type_ != kUninitialized);
-    return ((type_ & kDouble) == kDouble);
-  }
-
-  inline bool IsString() {
-    ASSERT(type_ != kUninitialized);
-    return ((type_ & kString) == kString);
-  }
-
-  inline bool IsNonPrimitive() {
-    ASSERT(type_ != kUninitialized);
-    return ((type_ & kNonPrimitive) == kNonPrimitive);
-  }
-
-  inline bool IsUninitialized() {
-    return type_ == kUninitialized;
-  }
-
-  const char* ToString() {
-    switch (type_) {
-      case kUnknown: return "Unknown";
-      case kPrimitive: return "Primitive";
-      case kNumber: return "Number";
-      case kInteger32: return "Integer32";
-      case kSmi: return "Smi";
-      case kInternalizedString: return "InternalizedString";
-      case kDouble: return "Double";
-      case kString: return "String";
-      case kNonPrimitive: return "Object";
-      case kUninitialized: return "Uninitialized";
-    }
-    UNREACHABLE();
-    return "Unreachable code";
-  }
-
- private:
-  enum Type {
-    kUnknown = 0,                // 0000000
-    kPrimitive = 0x10,           // 0010000
-    kNumber = 0x11,              // 0010001
-    kInteger32 = 0x13,           // 0010011
-    kSmi = 0x17,                 // 0010111
-    kDouble = 0x19,              // 0011001
-    kString = 0x30,              // 0110000
-    kInternalizedString = 0x32,  // 0110010
-    kNonPrimitive = 0x40,        // 1000000
-    kUninitialized = 0x7f        // 1111111
-  };
-
-  explicit inline TypeInfo(Type t) : type_(t) { }
-
-  Type type_;
-};
+  return false;
+}
 
 
 enum StringStubFeedback {
   DEFAULT_STRING_STUB = 0,
   STRING_INDEX_OUT_OF_BOUNDS = 1
 };
 
 
 // Forward declarations.
 class CompilationInfo;
@@ skipping 115 matching lines @@
   Isolate* isolate_;
   Zone* zone_;
   Handle<UnseededNumberDictionary> dictionary_;
 
   DISALLOW_COPY_AND_ASSIGN(TypeFeedbackOracle);
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_TYPE_INFO_H_