- Eliminated superfluous type tests in IsMatch.

src/objects.cc

 // Copyright 2006-2008 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 5326 matching lines @@
 
 // The NumberKey uses carries the uint32_t as key.
 // This avoids allocation in HasProperty.
 class NumberKey : public HashTableKey {
  public:
   explicit NumberKey(uint32_t number) {
     number_ = number;
   }
 
  private:
-  bool IsMatch(Object* other) {
-    return number_ == ToUint32(other);
+  bool IsMatch(Object* number) {
+    return number_ == ToUint32(number);
   }
 
   // Thomas Wang, Integer Hash Functions.
   // http://www.concentric.net/~Ttwang/tech/inthash.htm
   static uint32_t ComputeHash(uint32_t key) {
     uint32_t hash = key;
     hash = ~hash + (hash << 15);  // hash = (hash << 15) - hash - 1;
     hash = hash ^ (hash >> 12);
     hash = hash + (hash << 2);
     hash = hash ^ (hash >> 4);
@@ skipping 25 matching lines @@
 };
 
 
 // StringKey simply carries a string object as key.
 class StringKey : public HashTableKey {
  public:
   explicit StringKey(String* string) {
     string_ = string;
   }
 
-  bool IsMatch(Object* other) {
-    if (!other->IsString()) return false;
-    return string_->Equals(String::cast(other));
+  bool IsMatch(Object* string) {
+    return string_->Equals(String::cast(string));
   }
 
   uint32_t Hash() { return StringHash(string_); }
 
   HashFunction GetHashFunction() { return StringHash; }
 
   Object* GetObject() { return string_; }
 
   static uint32_t StringHash(Object* obj) {
     return String::cast(obj)->Hash();
   }
 
   bool IsStringKey() { return true; }
 
   String* string_;
 };
 
 // Utf8SymbolKey carries a vector of chars as key.
 class Utf8SymbolKey : public HashTableKey {
  public:
   explicit Utf8SymbolKey(Vector<const char> string)
       : string_(string), length_field_(0) { }
 
-  bool IsMatch(Object* other) {
-    if (!other->IsString()) return false;
-    return String::cast(other)->IsEqualTo(string_);
+  bool IsMatch(Object* string) {
+    return String::cast(string)->IsEqualTo(string_);
   }
 
   HashFunction GetHashFunction() {
     return StringHash;
   }
 
   uint32_t Hash() {
     if (length_field_ != 0) return length_field_ >> String::kHashShift;
     unibrow::Utf8InputBuffer<> buffer(string_.start(),
                                       static_cast<unsigned>(string_.length()));
@@ skipping 23 matching lines @@
 
 // SymbolKey carries a string/symbol object as key.
 class SymbolKey : public HashTableKey {
  public:
   explicit SymbolKey(String* string) : string_(string) { }
 
   HashFunction GetHashFunction() {
     return StringHash;
   }
 
-  bool IsMatch(Object* other) {
-    if (!other->IsString()) return false;
-    return String::cast(other)->Equals(string_);
+  bool IsMatch(Object* string) {
+    return String::cast(string)->Equals(string_);
   }
 
   uint32_t Hash() { return string_->Hash(); }
 
   Object* GetObject() {
     // If the string is a cons string, attempt to flatten it so that
     // symbols will most often be flat strings.
     if (string_->IsConsString()) {
       ConsString* cons_string = ConsString::cast(string_);
       cons_string->TryFlatten();
@@ skipping 226 matching lines @@
 }
 
 
 // SymbolsKey used for HashTable where key is array of symbols.
 class SymbolsKey : public HashTableKey {
  public:
   explicit SymbolsKey(FixedArray* symbols) {
     symbols_ = symbols;
   }
 
-  bool IsMatch(Object* other) {
-    if (!other->IsFixedArray()) return false;
-    FixedArray* o = FixedArray::cast(other);
+  bool IsMatch(Object* symbols) {
+    FixedArray* o = FixedArray::cast(symbols);
     int len = symbols_->length();
     if (o->length() != len) return false;
     for (int i = 0; i < len; i++) {
       if (o->get(i) != symbols_->get(i)) return false;
     }
     return true;
   }
 
   uint32_t Hash() { return SymbolsHash(symbols_); }
 
@@ skipping 700 matching lines @@
   // No break point.
   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();
 }
 
 
 } }  // namespace v8::internal