Revert "Unify and fix checkers for duplicate object literal properties."

This reverts commit 12c68518bd2c74dc4e44d928c84c17f98ca63359.
(r17114)

R=mstarzinger@chromium.org
TBR=mstarzinger@chromium.org

Review URL: https://codereview.chromium.org/26732006

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@17122 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/conversions.cc

@@ -31,7 +31,6 @@
 
 #include "conversions-inl.h"
 #include "dtoa.h"
-#include "list-inl.h"
 #include "strtod.h"
 #include "utils.h"
 

src/parser.cc

@@ -3771,6 +3771,84 @@ Handle<Object> Parser::GetBoilerplateValue(Expression* expression) {
 }
 
 
+// Validation per 11.1.5 Object Initialiser
+class ObjectLiteralPropertyChecker {
+ public:
+  ObjectLiteralPropertyChecker(Parser* parser, LanguageMode language_mode) :
+    props_(Literal::Match),
+    parser_(parser),
+    language_mode_(language_mode) {
+  }
+
+  void CheckProperty(
+    ObjectLiteral::Property* property,
+    Scanner::Location loc,
+    bool* ok);
+
+ private:
+  enum PropertyKind {
+    kGetAccessor = 0x01,
+    kSetAccessor = 0x02,
+    kAccessor = kGetAccessor | kSetAccessor,
+    kData = 0x04
+  };
+
+  static intptr_t GetPropertyKind(ObjectLiteral::Property* property) {
+    switch (property->kind()) {
+      case ObjectLiteral::Property::GETTER:
+        return kGetAccessor;
+      case ObjectLiteral::Property::SETTER:
+        return kSetAccessor;
+      default:
+        return kData;
+    }
+  }
+
+  HashMap props_;
+  Parser* parser_;
+  LanguageMode language_mode_;
+};
+
+
+void ObjectLiteralPropertyChecker::CheckProperty(
+    ObjectLiteral::Property* property,
+    Scanner::Location loc,
+    bool* ok) {
+  ASSERT(property != NULL);
+  Literal* literal = property->key();
+  HashMap::Entry* entry = props_.Lookup(literal, literal->Hash(), true);
+  intptr_t prev = reinterpret_cast<intptr_t> (entry->value);
+  intptr_t curr = GetPropertyKind(property);
+
+  // Duplicate data properties are illegal in strict or extended mode.
+  if (language_mode_ != CLASSIC_MODE && (curr & prev & kData) != 0) {
+    parser_->ReportMessageAt(loc, "strict_duplicate_property",
+                             Vector<const char*>::empty());
+    *ok = false;
+    return;
+  }
+  // Data property conflicting with an accessor.
+  if (((curr & kData) && (prev & kAccessor)) ||
+      ((prev & kData) && (curr & kAccessor))) {
+    parser_->ReportMessageAt(loc, "accessor_data_property",
+                             Vector<const char*>::empty());
+    *ok = false;
+    return;
+  }
+  // Two accessors of the same type conflicting
+  if ((curr & prev & kAccessor) != 0) {
+    parser_->ReportMessageAt(loc, "accessor_get_set",
+                             Vector<const char*>::empty());
+    *ok = false;
+    return;
+  }
+
+  // Update map
+  entry->value = reinterpret_cast<void*> (prev | curr);
+  *ok = true;
+}
+
+
 void Parser::BuildObjectLiteralConstantProperties(
     ZoneList<ObjectLiteral::Property*>* properties,
     Handle<FixedArray> constant_properties,
@@ -3843,17 +3921,12 @@ void Parser::BuildObjectLiteralConstantProperties(
 }
 
 
-// Force instantiation of template instances class.
-template void ObjectLiteralChecker<Parser>::CheckProperty(
-    Token::Value property, PropertyKind type, bool* ok);
-
-
 ObjectLiteral::Property* Parser::ParseObjectLiteralGetSet(bool is_getter,
                                                           bool* ok) {
   // Special handling of getter and setter syntax:
   // { ... , get foo() { ... }, ... , set foo(v) { ... v ... } , ... }
-  // We have already read the "get" or "set" keyword and the name.
-  Token::Value next = scanner().current_token();
+  // We have already read the "get" or "set" keyword.
+  Token::Value next = Next();
   bool is_keyword = Token::IsKeyword(next);
   if (next == Token::IDENTIFIER || next == Token::NUMBER ||
       next == Token::FUTURE_RESERVED_WORD ||
@@ -3895,8 +3968,7 @@ Expression* Parser::ParseObjectLiteral(bool* ok) {
   int number_of_boilerplate_properties = 0;
   bool has_function = false;
 
-  ObjectLiteralChecker<Parser> checker(this, &scanner_,
-                                       top_scope_->language_mode());
+  ObjectLiteralPropertyChecker checker(this, top_scope_->language_mode());
 
   Expect(Token::LBRACE, CHECK_OK);
 
@@ -3906,6 +3978,9 @@ Expression* Parser::ParseObjectLiteral(bool* ok) {
     Literal* key = NULL;
     Token::Value next = peek();
 
+    // Location of the property name token
+    Scanner::Location loc = scanner().peek_location();
+
     switch (next) {
       case Token::FUTURE_RESERVED_WORD:
       case Token::FUTURE_STRICT_RESERVED_WORD:
@@ -3917,14 +3992,15 @@ Expression* Parser::ParseObjectLiteral(bool* ok) {
         if (fni_ != NULL) fni_->PushLiteralName(id);
 
         if ((is_getter || is_setter) && peek() != Token::COLON) {
-            // Validate the property.
-            PropertyKind type = is_getter ? kGetterProperty : kSetterProperty;
-            checker.CheckProperty(Next(), type, CHECK_OK);
+            // Update loc to point to the identifier
+            loc = scanner().peek_location();
             ObjectLiteral::Property* property =
                 ParseObjectLiteralGetSet(is_getter, CHECK_OK);
             if (IsBoilerplateProperty(property)) {
               number_of_boilerplate_properties++;
             }
+            // Validate the property.
+            checker.CheckProperty(property, loc, CHECK_OK);
             properties->Add(property, zone());
             if (peek() != Token::RBRACE) Expect(Token::COMMA, CHECK_OK);
 
@@ -3975,9 +4051,6 @@ Expression* Parser::ParseObjectLiteral(bool* ok) {
         }
     }
 
-    // Validate the property
-    checker.CheckProperty(next, kValueProperty, CHECK_OK);
-
     Expect(Token::COLON, CHECK_OK);
     Expression* value = ParseAssignmentExpression(true, CHECK_OK);
 
@@ -3995,6 +4068,8 @@ Expression* Parser::ParseObjectLiteral(bool* ok) {
 
     // Count CONSTANT or COMPUTED properties to maintain the enumeration order.
     if (IsBoilerplateProperty(property)) number_of_boilerplate_properties++;
+    // Validate the property
+    checker.CheckProperty(property, loc, CHECK_OK);
     properties->Add(property, zone());
 
     // TODO(1240767): Consider allowing trailing comma.

src/parser.h

@@ -463,7 +463,7 @@ class Parser BASE_EMBEDDED {
 
   void ReportMessageAt(Scanner::Location loc,
                        const char* message,
-                       Vector<const char*> args = Vector<const char*>::empty());
+                       Vector<const char*> args);
   void ReportMessageAt(Scanner::Location loc,
                        const char* message,
                        Vector<Handle<String> > args);
@@ -879,7 +879,6 @@ class Parser BASE_EMBEDDED {
   CompilationInfo* info_;
   friend class BlockState;
   friend class FunctionState;
-  friend class ObjectLiteralChecker<Parser>;
 };
 
 

src/preparser.cc

@@ -1231,6 +1231,39 @@ PreParser::Expression PreParser::ParseArrayLiteral(bool* ok) {
   return Expression::Default();
 }
 
+void PreParser::CheckDuplicate(DuplicateFinder* finder,
+                               i::Token::Value property,
+                               int type,
+                               bool* ok) {
+  int old_type;
+  if (property == i::Token::NUMBER) {
+    old_type = finder->AddNumber(scanner_->literal_ascii_string(), type);
+  } else if (scanner_->is_literal_ascii()) {
+    old_type = finder->AddAsciiSymbol(scanner_->literal_ascii_string(),
+                                      type);
+  } else {
+    old_type = finder->AddUtf16Symbol(scanner_->literal_utf16_string(), type);
+  }
+  if (HasConflict(old_type, type)) {
+    if (IsDataDataConflict(old_type, type)) {
+      // Both are data properties.
+      if (is_classic_mode()) return;
+      ReportMessageAt(scanner_->location(),
+                      "strict_duplicate_property", NULL);
+    } else if (IsDataAccessorConflict(old_type, type)) {
+      // Both a data and an accessor property with the same name.
+      ReportMessageAt(scanner_->location(),
+                      "accessor_data_property", NULL);
+    } else {
+      ASSERT(IsAccessorAccessorConflict(old_type, type));
+      // Both accessors of the same type.
+      ReportMessageAt(scanner_->location(),
+                      "accessor_get_set", NULL);
+    }
+    *ok = false;
+  }
+}
+
 
 PreParser::Expression PreParser::ParseObjectLiteral(bool* ok) {
   // ObjectLiteral ::
@@ -1239,9 +1272,8 @@ PreParser::Expression PreParser::ParseObjectLiteral(bool* ok) {
   //     | (('get' | 'set') (IdentifierName | String | Number) FunctionLiteral)
   //    )*[','] '}'
 
-  i::ObjectLiteralChecker<PreParser> checker(this, scanner_, language_mode());
-
   Expect(i::Token::LBRACE, CHECK_OK);
+  DuplicateFinder duplicate_finder(scanner_->unicode_cache());
   while (peek() != i::Token::RBRACE) {
     i::Token::Value next = peek();
     switch (next) {
@@ -1266,31 +1298,30 @@ PreParser::Expression PreParser::ParseObjectLiteral(bool* ok) {
             if (!is_keyword) {
               LogSymbol();
             }
-            i::PropertyKind type = is_getter ? i::kGetterProperty
-                                             : i::kSetterProperty;
-            checker.CheckProperty(name, type, CHECK_OK);
+            PropertyType type = is_getter ? kGetterProperty : kSetterProperty;
+            CheckDuplicate(&duplicate_finder, name, type, CHECK_OK);
             ParseFunctionLiteral(false, CHECK_OK);
             if (peek() != i::Token::RBRACE) {
               Expect(i::Token::COMMA, CHECK_OK);
             }
             continue;  // restart the while
         }
-        checker.CheckProperty(next, i::kValueProperty, CHECK_OK);
+        CheckDuplicate(&duplicate_finder, next, kValueProperty, CHECK_OK);
         break;
       }
       case i::Token::STRING:
         Consume(next);
-        checker.CheckProperty(next, i::kValueProperty, CHECK_OK);
+        CheckDuplicate(&duplicate_finder, next, kValueProperty, CHECK_OK);
         GetStringSymbol();
         break;
       case i::Token::NUMBER:
         Consume(next);
-        checker.CheckProperty(next, i::kValueProperty, CHECK_OK);
+        CheckDuplicate(&duplicate_finder, next, kValueProperty, CHECK_OK);
         break;
       default:
         if (i::Token::IsKeyword(next)) {
           Consume(next);
-          checker.CheckProperty(next, i::kValueProperty, CHECK_OK);
+          CheckDuplicate(&duplicate_finder, next, kValueProperty, CHECK_OK);
         } else {
           // Unexpected token.
           *ok = false;
@@ -1371,7 +1402,7 @@ PreParser::Expression PreParser::ParseFunctionLiteral(bool is_generator,
   Expect(i::Token::LPAREN, CHECK_OK);
   int start_position = scanner_->location().beg_pos;
   bool done = (peek() == i::Token::RPAREN);
-  i::DuplicateFinder duplicate_finder(scanner_->unicode_cache());
+  DuplicateFinder duplicate_finder(scanner_->unicode_cache());
   while (!done) {
     Identifier id = ParseIdentifier(CHECK_OK);
     if (!id.IsValidStrictVariable()) {
@@ -1663,4 +1694,139 @@ bool PreParser::peek_any_identifier() {
          next == i::Token::YIELD;
 }
 
+
+int DuplicateFinder::AddAsciiSymbol(i::Vector<const char> key, int value) {
+  return AddSymbol(i::Vector<const byte>::cast(key), true, value);
+}
+
+
+int DuplicateFinder::AddUtf16Symbol(i::Vector<const uint16_t> key, int value) {
+  return AddSymbol(i::Vector<const byte>::cast(key), false, value);
+}
+
+int DuplicateFinder::AddSymbol(i::Vector<const byte> key,
+                               bool is_ascii,
+                               int value) {
+  uint32_t hash = Hash(key, is_ascii);
+  byte* encoding = BackupKey(key, is_ascii);
+  i::HashMap::Entry* entry = map_.Lookup(encoding, hash, true);
+  int old_value = static_cast<int>(reinterpret_cast<intptr_t>(entry->value));
+  entry->value =
+    reinterpret_cast<void*>(static_cast<intptr_t>(value | old_value));
+  return old_value;
+}
+
+
+int DuplicateFinder::AddNumber(i::Vector<const char> key, int value) {
+  ASSERT(key.length() > 0);
+  // Quick check for already being in canonical form.
+  if (IsNumberCanonical(key)) {
+    return AddAsciiSymbol(key, value);
+  }
+
+  int flags = i::ALLOW_HEX | i::ALLOW_OCTAL | i::ALLOW_IMPLICIT_OCTAL |
+      i::ALLOW_BINARY;
+  double double_value = StringToDouble(unicode_constants_, key, flags, 0.0);
+  int length;
+  const char* string;
+  if (!std::isfinite(double_value)) {
+    string = "Infinity";
+    length = 8;  // strlen("Infinity");
+  } else {
+    string = DoubleToCString(double_value,
+                             i::Vector<char>(number_buffer_, kBufferSize));
+    length = i::StrLength(string);
+  }
+  return AddSymbol(i::Vector<const byte>(reinterpret_cast<const byte*>(string),
+                                         length), true, value);
+}
+
+
+bool DuplicateFinder::IsNumberCanonical(i::Vector<const char> number) {
+  // Test for a safe approximation of number literals that are already
+  // in canonical form: max 15 digits, no leading zeroes, except an
+  // integer part that is a single zero, and no trailing zeros below
+  // the decimal point.
+  int pos = 0;
+  int length = number.length();
+  if (number.length() > 15) return false;
+  if (number[pos] == '0') {
+    pos++;
+  } else {
+    while (pos < length &&
+           static_cast<unsigned>(number[pos] - '0') <= ('9' - '0')) pos++;
+  }
+  if (length == pos) return true;
+  if (number[pos] != '.') return false;
+  pos++;
+  bool invalid_last_digit = true;
+  while (pos < length) {
+    byte digit = number[pos] - '0';
+    if (digit > '9' - '0') return false;
+    invalid_last_digit = (digit == 0);
+    pos++;
+  }
+  return !invalid_last_digit;
+}
+
+
+uint32_t DuplicateFinder::Hash(i::Vector<const byte> key, bool is_ascii) {
+  // Primitive hash function, almost identical to the one used
+  // for strings (except that it's seeded by the length and ASCII-ness).
+  int length = key.length();
+  uint32_t hash = (length << 1) | (is_ascii ? 1 : 0) ;
+  for (int i = 0; i < length; i++) {
+    uint32_t c = key[i];
+    hash = (hash + c) * 1025;
+    hash ^= (hash >> 6);
+  }
+  return hash;
+}
+
+
+bool DuplicateFinder::Match(void* first, void* second) {
+  // Decode lengths.
+  // Length + ASCII-bit is encoded as base 128, most significant heptet first,
+  // with a 8th bit being non-zero while there are more heptets.
+  // The value encodes the number of bytes following, and whether the original
+  // was ASCII.
+  byte* s1 = reinterpret_cast<byte*>(first);
+  byte* s2 = reinterpret_cast<byte*>(second);
+  uint32_t length_ascii_field = 0;
+  byte c1;
+  do {
+    c1 = *s1;
+    if (c1 != *s2) return false;
+    length_ascii_field = (length_ascii_field << 7) | (c1 & 0x7f);
+    s1++;
+    s2++;
+  } while ((c1 & 0x80) != 0);
+  int length = static_cast<int>(length_ascii_field >> 1);
+  return memcmp(s1, s2, length) == 0;
+}
+
+
+byte* DuplicateFinder::BackupKey(i::Vector<const byte> bytes,
+                                 bool is_ascii) {
+  uint32_t ascii_length = (bytes.length() << 1) | (is_ascii ? 1 : 0);
+  backing_store_.StartSequence();
+  // Emit ascii_length as base-128 encoded number, with the 7th bit set
+  // on the byte of every heptet except the last, least significant, one.
+  if (ascii_length >= (1 << 7)) {
+    if (ascii_length >= (1 << 14)) {
+      if (ascii_length >= (1 << 21)) {
+        if (ascii_length >= (1 << 28)) {
+          backing_store_.Add(static_cast<byte>((ascii_length >> 28) | 0x80));
+        }
+        backing_store_.Add(static_cast<byte>((ascii_length >> 21) | 0x80u));
+      }
+      backing_store_.Add(static_cast<byte>((ascii_length >> 14) | 0x80u));
+    }
+    backing_store_.Add(static_cast<byte>((ascii_length >> 7) | 0x80u));
+  }
+  backing_store_.Add(static_cast<byte>(ascii_length & 0x7f));
+
+  backing_store_.AddBlock(bytes);
+  return backing_store_.EndSequence().start();
+}
 } }  // v8::preparser

src/preparser.h

@@ -35,98 +35,9 @@
 namespace v8 {
 
 namespace internal {
-
-// Used to detect duplicates in object literals. Each of the values
-// kGetterProperty, kSetterProperty and kValueProperty represents
-// a type of object literal property. When parsing a property, its
-// type value is stored in the DuplicateFinder for the property name.
-// Values are chosen so that having intersection bits means the there is
-// an incompatibility.
-// I.e., you can add a getter to a property that already has a setter, since
-// kGetterProperty and kSetterProperty doesn't intersect, but not if it
-// already has a getter or a value. Adding the getter to an existing
-// setter will store the value (kGetterProperty | kSetterProperty), which
-// is incompatible with adding any further properties.
-enum PropertyKind {
-  kNone = 0,
-  // Bit patterns representing different object literal property types.
-  kGetterProperty = 1,
-  kSetterProperty = 2,
-  kValueProperty = 7,
-  // Helper constants.
-  kValueFlag = 4
-};
-
-
-// Validation per 11.1.5 Object Initialiser
-template<typename P>
-class ObjectLiteralChecker {
- public:
-  ObjectLiteralChecker(P* parser, Scanner* scanner, LanguageMode mode)
-      : parser_(parser),
-        scanner_(scanner),
-        finder_(scanner->unicode_cache()),
-        language_mode_(mode) { }
-
-  void CheckProperty(Token::Value property, PropertyKind type, bool* ok);
-
- private:
-  // Checks the type of conflict based on values coming from PropertyType.
-  bool HasConflict(PropertyKind type1, PropertyKind type2) {
-    return (type1 & type2) != 0;
-  }
-  bool IsDataDataConflict(PropertyKind type1, PropertyKind type2) {
-    return ((type1 & type2) & kValueFlag) != 0;
-  }
-  bool IsDataAccessorConflict(PropertyKind type1, PropertyKind type2) {
-    return ((type1 ^ type2) & kValueFlag) != 0;
-  }
-  bool IsAccessorAccessorConflict(PropertyKind type1, PropertyKind type2) {
-    return ((type1 | type2) & kValueFlag) == 0;
-  }
-
-  P* parser_;
-  Scanner* scanner_;
-  DuplicateFinder finder_;
-  LanguageMode language_mode_;
-};
-
-
-template<typename P>
-void ObjectLiteralChecker<P>::CheckProperty(Token::Value property,
-                                            PropertyKind type,
-                                            bool* ok) {
-  int old;
-  if (property == Token::NUMBER) {
-    old = finder_.AddNumber(scanner_->literal_ascii_string(), type);
-  } else if (scanner_->is_literal_ascii()) {
-    old = finder_.AddAsciiSymbol(scanner_->literal_ascii_string(), type);
-  } else {
-    old = finder_.AddUtf16Symbol(scanner_->literal_utf16_string(), type);
-  }
-  PropertyKind old_type = static_cast<PropertyKind>(old);
-  if (HasConflict(old_type, type)) {
-    if (IsDataDataConflict(old_type, type)) {
-      // Both are data properties.
-      if (language_mode_ == CLASSIC_MODE) return;
-      parser_->ReportMessageAt(scanner_->location(),
-                               "strict_duplicate_property");
-    } else if (IsDataAccessorConflict(old_type, type)) {
-      // Both a data and an accessor property with the same name.
-      parser_->ReportMessageAt(scanner_->location(),
-                               "accessor_data_property");
-    } else {
-      ASSERT(IsAccessorAccessorConflict(old_type, type));
-      // Both accessors of the same type.
-      parser_->ReportMessageAt(scanner_->location(),
-                               "accessor_get_set");
-    }
-    *ok = false;
-  }
+class UnicodeCache;
 }
 
-}  // v8::internal
-
 namespace preparser {
 
 typedef uint8_t byte;
@@ -146,6 +57,53 @@ typedef uint8_t byte;
 
 namespace i = v8::internal;
 
+class DuplicateFinder {
+ public:
+  explicit DuplicateFinder(i::UnicodeCache* constants)
+      : unicode_constants_(constants),
+        backing_store_(16),
+        map_(&Match) { }
+
+  int AddAsciiSymbol(i::Vector<const char> key, int value);
+  int AddUtf16Symbol(i::Vector<const uint16_t> key, int value);
+  // Add a a number literal by converting it (if necessary)
+  // to the string that ToString(ToNumber(literal)) would generate.
+  // and then adding that string with AddAsciiSymbol.
+  // This string is the actual value used as key in an object literal,
+  // and the one that must be different from the other keys.
+  int AddNumber(i::Vector<const char> key, int value);
+
+ private:
+  int AddSymbol(i::Vector<const byte> key, bool is_ascii, int value);
+  // Backs up the key and its length in the backing store.
+  // The backup is stored with a base 127 encoding of the
+  // length (plus a bit saying whether the string is ASCII),
+  // followed by the bytes of the key.
+  byte* BackupKey(i::Vector<const byte> key, bool is_ascii);
+
+  // Compare two encoded keys (both pointing into the backing store)
+  // for having the same base-127 encoded lengths and ASCII-ness,
+  // and then having the same 'length' bytes following.
+  static bool Match(void* first, void* second);
+  // Creates a hash from a sequence of bytes.
+  static uint32_t Hash(i::Vector<const byte> key, bool is_ascii);
+  // Checks whether a string containing a JS number is its canonical
+  // form.
+  static bool IsNumberCanonical(i::Vector<const char> key);
+
+  // Size of buffer. Sufficient for using it to call DoubleToCString in
+  // from conversions.h.
+  static const int kBufferSize = 100;
+
+  i::UnicodeCache* unicode_constants_;
+  // Backing store used to store strings used as hashmap keys.
+  i::SequenceCollector<unsigned char> backing_store_;
+  i::HashMap map_;
+  // Buffer used for string->number->canonical string conversions.
+  char number_buffer_[kBufferSize];
+};
+
+
 class PreParser {
  public:
   enum PreParseResult {
@@ -225,6 +183,45 @@ class PreParser {
                                       i::ParserRecorder* log);
 
  private:
+  // Used to detect duplicates in object literals. Each of the values
+  // kGetterProperty, kSetterProperty and kValueProperty represents
+  // a type of object literal property. When parsing a property, its
+  // type value is stored in the DuplicateFinder for the property name.
+  // Values are chosen so that having intersection bits means the there is
+  // an incompatibility.
+  // I.e., you can add a getter to a property that already has a setter, since
+  // kGetterProperty and kSetterProperty doesn't intersect, but not if it
+  // already has a getter or a value. Adding the getter to an existing
+  // setter will store the value (kGetterProperty | kSetterProperty), which
+  // is incompatible with adding any further properties.
+  enum PropertyType {
+    kNone = 0,
+    // Bit patterns representing different object literal property types.
+    kGetterProperty = 1,
+    kSetterProperty = 2,
+    kValueProperty = 7,
+    // Helper constants.
+    kValueFlag = 4
+  };
+
+  // Checks the type of conflict based on values coming from PropertyType.
+  bool HasConflict(int type1, int type2) { return (type1 & type2) != 0; }
+  bool IsDataDataConflict(int type1, int type2) {
+    return ((type1 & type2) & kValueFlag) != 0;
+  }
+  bool IsDataAccessorConflict(int type1, int type2) {
+    return ((type1 ^ type2) & kValueFlag) != 0;
+  }
+  bool IsAccessorAccessorConflict(int type1, int type2) {
+    return ((type1 | type2) & kValueFlag) == 0;
+  }
+
+
+  void CheckDuplicate(DuplicateFinder* finder,
+                      i::Token::Value property,
+                      int type,
+                      bool* ok);
+
   // These types form an algebra over syntactic categories that is just
   // rich enough to let us recognize and propagate the constructs that
   // are either being counted in the preparser data, or is important
@@ -534,7 +531,7 @@ class PreParser {
   void ReportUnexpectedToken(i::Token::Value token);
   void ReportMessageAt(i::Scanner::Location location,
                        const char* type,
-                       const char* name_opt = NULL) {
+                       const char* name_opt) {
     log_->LogMessage(location.beg_pos, location.end_pos, type, name_opt);
   }
   void ReportMessageAt(int start_pos,
@@ -689,10 +686,7 @@ class PreParser {
   bool allow_generators_;
   bool allow_for_of_;
   bool parenthesized_function_;
-
-  friend class i::ObjectLiteralChecker<PreParser>;
 };
-
 } }  // v8::preparser
 
 #endif  // V8_PREPARSER_H

src/scanner.cc

@@ -27,14 +27,10 @@
 
 // Features shared by parsing and pre-parsing scanners.
 
-#include <cmath>
-
 #include "scanner.h"
 
 #include "../include/v8stdint.h"
 #include "char-predicates-inl.h"
-#include "conversions-inl.h"
-#include "list-inl.h"
 
 namespace v8 {
 namespace internal {
@@ -1112,140 +1108,4 @@ bool Scanner::ScanRegExpFlags() {
   return true;
 }
 
-
-int DuplicateFinder::AddAsciiSymbol(Vector<const char> key, int value) {
-  return AddSymbol(Vector<const byte>::cast(key), true, value);
-}
-
-
-int DuplicateFinder::AddUtf16Symbol(Vector<const uint16_t> key, int value) {
-  return AddSymbol(Vector<const byte>::cast(key), false, value);
-}
-
-
-int DuplicateFinder::AddSymbol(Vector<const byte> key,
-                               bool is_ascii,
-                               int value) {
-  uint32_t hash = Hash(key, is_ascii);
-  byte* encoding = BackupKey(key, is_ascii);
-  HashMap::Entry* entry = map_.Lookup(encoding, hash, true);
-  int old_value = static_cast<int>(reinterpret_cast<intptr_t>(entry->value));
-  entry->value =
-    reinterpret_cast<void*>(static_cast<intptr_t>(value | old_value));
-  return old_value;
-}
-
-
-int DuplicateFinder::AddNumber(Vector<const char> key, int value) {
-  ASSERT(key.length() > 0);
-  // Quick check for already being in canonical form.
-  if (IsNumberCanonical(key)) {
-    return AddAsciiSymbol(key, value);
-  }
-
-  int flags = ALLOW_HEX | ALLOW_OCTAL | ALLOW_IMPLICIT_OCTAL | ALLOW_BINARY;
-  double double_value = StringToDouble(unicode_constants_, key, flags, 0.0);
-  int length;
-  const char* string;
-  if (!std::isfinite(double_value)) {
-    string = "Infinity";
-    length = 8;  // strlen("Infinity");
-  } else {
-    string = DoubleToCString(double_value,
-                             Vector<char>(number_buffer_, kBufferSize));
-    length = StrLength(string);
-  }
-  return AddSymbol(Vector<const byte>(reinterpret_cast<const byte*>(string),
-                                      length), true, value);
-}
-
-
-bool DuplicateFinder::IsNumberCanonical(Vector<const char> number) {
-  // Test for a safe approximation of number literals that are already
-  // in canonical form: max 15 digits, no leading zeroes, except an
-  // integer part that is a single zero, and no trailing zeros below
-  // the decimal point.
-  int pos = 0;
-  int length = number.length();
-  if (number.length() > 15) return false;
-  if (number[pos] == '0') {
-    pos++;
-  } else {
-    while (pos < length &&
-           static_cast<unsigned>(number[pos] - '0') <= ('9' - '0')) pos++;
-  }
-  if (length == pos) return true;
-  if (number[pos] != '.') return false;
-  pos++;
-  bool invalid_last_digit = true;
-  while (pos < length) {
-    byte digit = number[pos] - '0';
-    if (digit > '9' - '0') return false;
-    invalid_last_digit = (digit == 0);
-    pos++;
-  }
-  return !invalid_last_digit;
-}
-
-
-uint32_t DuplicateFinder::Hash(Vector<const byte> key, bool is_ascii) {
-  // Primitive hash function, almost identical to the one used
-  // for strings (except that it's seeded by the length and ASCII-ness).
-  int length = key.length();
-  uint32_t hash = (length << 1) | (is_ascii ? 1 : 0) ;
-  for (int i = 0; i < length; i++) {
-    uint32_t c = key[i];
-    hash = (hash + c) * 1025;
-    hash ^= (hash >> 6);
-  }
-  return hash;
-}
-
-
-bool DuplicateFinder::Match(void* first, void* second) {
-  // Decode lengths.
-  // Length + ASCII-bit is encoded as base 128, most significant heptet first,
-  // with a 8th bit being non-zero while there are more heptets.
-  // The value encodes the number of bytes following, and whether the original
-  // was ASCII.
-  byte* s1 = reinterpret_cast<byte*>(first);
-  byte* s2 = reinterpret_cast<byte*>(second);
-  uint32_t length_ascii_field = 0;
-  byte c1;
-  do {
-    c1 = *s1;
-    if (c1 != *s2) return false;
-    length_ascii_field = (length_ascii_field << 7) | (c1 & 0x7f);
-    s1++;
-    s2++;
-  } while ((c1 & 0x80) != 0);
-  int length = static_cast<int>(length_ascii_field >> 1);
-  return memcmp(s1, s2, length) == 0;
-}
-
-
-byte* DuplicateFinder::BackupKey(Vector<const byte> bytes,
-                                 bool is_ascii) {
-  uint32_t ascii_length = (bytes.length() << 1) | (is_ascii ? 1 : 0);
-  backing_store_.StartSequence();
-  // Emit ascii_length as base-128 encoded number, with the 7th bit set
-  // on the byte of every heptet except the last, least significant, one.
-  if (ascii_length >= (1 << 7)) {
-    if (ascii_length >= (1 << 14)) {
-      if (ascii_length >= (1 << 21)) {
-        if (ascii_length >= (1 << 28)) {
-          backing_store_.Add(static_cast<byte>((ascii_length >> 28) | 0x80));
-        }
-        backing_store_.Add(static_cast<byte>((ascii_length >> 21) | 0x80u));
-      }
-      backing_store_.Add(static_cast<byte>((ascii_length >> 14) | 0x80u));
-    }
-    backing_store_.Add(static_cast<byte>((ascii_length >> 7) | 0x80u));
-  }
-  backing_store_.Add(static_cast<byte>(ascii_length & 0x7f));
-
-  backing_store_.AddBlock(bytes);
-  return backing_store_.EndSequence().start();
-}
-
 } }  // namespace v8::internal

src/scanner.h

@@ -34,8 +34,6 @@
 #include "char-predicates.h"
 #include "checks.h"
 #include "globals.h"
-#include "hashmap.h"
-#include "list.h"
 #include "token.h"
 #include "unicode-inl.h"
 #include "utils.h"
@@ -123,10 +121,9 @@ class Utf16CharacterStream {
 };
 
 
+class UnicodeCache {
 // ---------------------------------------------------------------------
 // Caching predicates used by scanners.
-
-class UnicodeCache {
  public:
   UnicodeCache() {}
   typedef unibrow::Utf8Decoder<512> Utf8Decoder;
@@ -151,56 +148,6 @@ class UnicodeCache {
 };
 
 
-// ---------------------------------------------------------------------
-// DuplicateFinder discovers duplicate symbols.
-
-class DuplicateFinder {
- public:
-  explicit DuplicateFinder(UnicodeCache* constants)
-      : unicode_constants_(constants),
-        backing_store_(16),
-        map_(&Match) { }
-
-  int AddAsciiSymbol(Vector<const char> key, int value);
-  int AddUtf16Symbol(Vector<const uint16_t> key, int value);
-  // Add a a number literal by converting it (if necessary)
-  // to the string that ToString(ToNumber(literal)) would generate.
-  // and then adding that string with AddAsciiSymbol.
-  // This string is the actual value used as key in an object literal,
-  // and the one that must be different from the other keys.
-  int AddNumber(Vector<const char> key, int value);
-
- private:
-  int AddSymbol(Vector<const byte> key, bool is_ascii, int value);
-  // Backs up the key and its length in the backing store.
-  // The backup is stored with a base 127 encoding of the
-  // length (plus a bit saying whether the string is ASCII),
-  // followed by the bytes of the key.
-  byte* BackupKey(Vector<const byte> key, bool is_ascii);
-
-  // Compare two encoded keys (both pointing into the backing store)
-  // for having the same base-127 encoded lengths and ASCII-ness,
-  // and then having the same 'length' bytes following.
-  static bool Match(void* first, void* second);
-  // Creates a hash from a sequence of bytes.
-  static uint32_t Hash(Vector<const byte> key, bool is_ascii);
-  // Checks whether a string containing a JS number is its canonical
-  // form.
-  static bool IsNumberCanonical(Vector<const char> key);
-
-  // Size of buffer. Sufficient for using it to call DoubleToCString in
-  // from conversions.h.
-  static const int kBufferSize = 100;
-
-  UnicodeCache* unicode_constants_;
-  // Backing store used to store strings used as hashmap keys.
-  SequenceCollector<unsigned char> backing_store_;
-  HashMap map_;
-  // Buffer used for string->number->canonical string conversions.
-  char number_buffer_[kBufferSize];
-};
-
-
 // ----------------------------------------------------------------------------
 // LiteralBuffer -  Collector of chars of literals.
 

test/preparser/preparser.status

@@ -27,6 +27,12 @@
 
 [
 [ALWAYS, {
+  # TODO(mstarzinger): Uhm, this is kind of embarrassing, but our parser
+  # does not catch some syntax errors with duplicate properties in object
+  # literals that our preparser actually caught. I will fix this glitch in a
+  # follow-up change.
+  'duplicate-property/*': [SKIP],
+
   # TODO(mstarzinger): This script parses but throws a TypeError when run.
   'non-alphanum': [FAIL],