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

src/preparser.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 1213 matching lines @@
     if (peek() != i::Token::RBRACK) {
       Expect(i::Token::COMMA, CHECK_OK);
     }
   }
   Expect(i::Token::RBRACK, CHECK_OK);
 
   scope_->NextMaterializedLiteralIndex();
   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 ::
   //   '{' (
   //       ((IdentifierName | String | Number) ':' AssignmentExpression)
   //     | (('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) {
       case i::Token::IDENTIFIER:
       case i::Token::FUTURE_RESERVED_WORD:
       case i::Token::FUTURE_STRICT_RESERVED_WORD: {
         bool is_getter = false;
         bool is_setter = false;
         ParseIdentifierNameOrGetOrSet(&is_getter, &is_setter, CHECK_OK);
         if ((is_getter || is_setter) && peek() != i::Token::COLON) {
             i::Token::Value name = Next();
             bool is_keyword = i::Token::IsKeyword(name);
             if (name != i::Token::IDENTIFIER &&
                 name != i::Token::FUTURE_RESERVED_WORD &&
                 name != i::Token::FUTURE_STRICT_RESERVED_WORD &&
                 name != i::Token::NUMBER &&
                 name != i::Token::STRING &&
                 !is_keyword) {
               *ok = false;
               return Expression::Default();
             }
             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;
           return Expression::Default();
         }
     }
 
     Expect(i::Token::COLON, CHECK_OK);
     ParseAssignmentExpression(true, CHECK_OK);
 
@@ skipping 60 matching lines @@
   // Parse function body.
   ScopeType outer_scope_type = scope_->type();
   bool inside_with = scope_->IsInsideWith();
   Scope function_scope(&scope_, kFunctionScope);
   function_scope.set_is_generator(is_generator);
   //  FormalParameterList ::
   //    '(' (Identifier)*[','] ')'
   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()) {
       StrictModeIdentifierViolation(scanner_->location(),
                                     "strict_param_name",
                                     id,
                                     CHECK_OK);
     }
     int prev_value;
     if (scanner_->is_literal_ascii()) {
@@ skipping 271 matching lines @@
 
 
 bool PreParser::peek_any_identifier() {
   i::Token::Value next = peek();
   return next == i::Token::IDENTIFIER ||
          next == i::Token::FUTURE_RESERVED_WORD ||
          next == i::Token::FUTURE_STRICT_RESERVED_WORD ||
          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