Remove unused code from DuplicateFinder.

BUG=v8:4947

Review-Url: https://codereview.chromium.org/2547493002
Cr-Commit-Position: refs/heads/master@{#41453}

src/parsing/duplicate-finder.cc

@@ -4,83 +4,26 @@
 
 #include "src/parsing/duplicate-finder.h"
 
-#include "src/conversions.h"
-#include "src/unicode-cache.h"
-
 namespace v8 {
 namespace internal {
 
-int DuplicateFinder::AddOneByteSymbol(Vector<const uint8_t> key, int value) {
-  return AddSymbol(key, true, value);
+bool DuplicateFinder::AddOneByteSymbol(Vector<const uint8_t> key) {
+  return AddSymbol(key, true);
 }
 
-int DuplicateFinder::AddTwoByteSymbol(Vector<const uint16_t> key, int value) {
-  return AddSymbol(Vector<const uint8_t>::cast(key), false, value);
+bool DuplicateFinder::AddTwoByteSymbol(Vector<const uint16_t> key) {
+  return AddSymbol(Vector<const uint8_t>::cast(key), false);
 }
 
-int DuplicateFinder::AddSymbol(Vector<const uint8_t> key, bool is_one_byte,
-                               int value) {
+bool DuplicateFinder::AddSymbol(Vector<const uint8_t> key, bool is_one_byte) {
   uint32_t hash = Hash(key, is_one_byte);
   byte* encoding = BackupKey(key, is_one_byte);
   base::HashMap::Entry* entry = map_.LookupOrInsert(encoding, hash);
   int old_value = static_cast<int>(reinterpret_cast<intptr_t>(entry->value));
-  entry->value =
-      reinterpret_cast<void*>(static_cast<intptr_t>(value | old_value));
+  entry->value = reinterpret_cast<void*>(1);
   return old_value;
 }
 
-int DuplicateFinder::AddNumber(Vector<const uint8_t> key, int value) {
-  DCHECK(key.length() > 0);
-  // Quick check for already being in canonical form.
-  if (IsNumberCanonical(key)) {
-    return AddOneByteSymbol(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 uint8_t> 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) {
-    uint8_t 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 uint8_t> key, bool is_one_byte) {
   // Primitive hash function, almost identical to the one used
   // for strings (except that it's seeded by the length and representation).

src/parsing/duplicate-finder.h

@@ -11,25 +11,16 @@
 namespace v8 {
 namespace internal {
 
-class UnicodeCache;
-
 // DuplicateFinder discovers duplicate symbols.
 class DuplicateFinder {
  public:
-  explicit DuplicateFinder(UnicodeCache* constants)
-      : unicode_constants_(constants), backing_store_(16), map_(&Match) {}
+  DuplicateFinder() : backing_store_(16), map_(&Match) {}
 
-  int AddOneByteSymbol(Vector<const uint8_t> key, int value);
-  int AddTwoByteSymbol(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 AddOneByteSymbol.
-  // 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 uint8_t> key, int value);
+  bool AddOneByteSymbol(Vector<const uint8_t> key);
+  bool AddTwoByteSymbol(Vector<const uint16_t> key);
 
  private:
-  int AddSymbol(Vector<const uint8_t> key, bool is_one_byte, int value);
+  bool AddSymbol(Vector<const uint8_t> key, bool is_one_byte);
   // 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 one byte),
@@ -40,22 +31,13 @@ class DuplicateFinder {
   // for having the same base-127 encoded lengths and representation.
   // 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 uint8_t> key, bool is_one_byte);
-  // Checks whether a string containing a JS number is its canonical
-  // form.
-  static bool IsNumberCanonical(Vector<const uint8_t> 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_;
   base::CustomMatcherHashMap map_;
-  // Buffer used for string->number->canonical string conversions.
-  char number_buffer_[kBufferSize];
 };
 
 }  // namespace internal

src/parsing/parser-base.h

@@ -1610,7 +1610,7 @@ ParserBase<Impl>::ParseAndClassifyIdentifier(bool* ok) {
     }
 
     if (classifier()->duplicate_finder() != nullptr &&
-        scanner()->FindSymbol(classifier()->duplicate_finder(), 1) != 0) {
+        scanner()->FindSymbol(classifier()->duplicate_finder())) {
       classifier()->RecordDuplicateFormalParameterError(scanner()->location());
     }
     return name;
@@ -2374,7 +2374,7 @@ ParserBase<Impl>::ParseObjectPropertyDefinition(ObjectLiteralChecker* checker,
       DCHECK(!*is_computed_name);
 
       if (classifier()->duplicate_finder() != nullptr &&
-          scanner()->FindSymbol(classifier()->duplicate_finder(), 1) != 0) {
+          scanner()->FindSymbol(classifier()->duplicate_finder())) {
         classifier()->RecordDuplicateFormalParameterError(
             scanner()->location());
       }

src/parsing/parser.cc

@@ -3159,7 +3159,7 @@ ZoneList<Statement*>* Parser::ParseFunction(
 
   FunctionState function_state(&function_state_, &scope_state_, function_scope);
 
-  DuplicateFinder duplicate_finder(scanner()->unicode_cache());
+  DuplicateFinder duplicate_finder;
   ExpressionClassifier formals_classifier(this, &duplicate_finder);
 
   if (IsGeneratorFunction(kind)) PrepareGeneratorVariables(&function_state);

src/parsing/preparser.cc

@@ -108,7 +108,7 @@ PreParser::PreParseResult PreParser::PreParseFunction(
 
   PreParserFormalParameters formals(function_scope);
   bool has_duplicate_parameters = false;
-  DuplicateFinder duplicate_finder(scanner()->unicode_cache());
+  DuplicateFinder duplicate_finder;
   std::unique_ptr<ExpressionClassifier> formals_classifier;
 
   // Parse non-arrow function parameters. For arrow functions, the parameters
@@ -198,7 +198,7 @@ PreParser::Expression PreParser::ParseFunctionLiteral(
   DeclarationScope* function_scope = NewFunctionScope(kind);
   function_scope->SetLanguageMode(language_mode);
   FunctionState function_state(&function_state_, &scope_state_, function_scope);
-  DuplicateFinder duplicate_finder(scanner()->unicode_cache());
+  DuplicateFinder duplicate_finder;
   ExpressionClassifier formals_classifier(this, &duplicate_finder);
   GetNextFunctionLiteralId();
 

src/parsing/scanner.cc

@@ -1600,14 +1600,13 @@ bool Scanner::ContainsDot() {
   return std::find(str.begin(), str.end(), '.') != str.end();
 }
 
-
-int Scanner::FindSymbol(DuplicateFinder* finder, int value) {
+bool Scanner::FindSymbol(DuplicateFinder* finder) {
   // TODO(vogelheim): Move this logic into the calling class; this can be fully
   //                  implemented using the public interface.
   if (is_literal_one_byte()) {
-    return finder->AddOneByteSymbol(literal_one_byte_string(), value);
+    return finder->AddOneByteSymbol(literal_one_byte_string());
   }
-  return finder->AddTwoByteSymbol(literal_two_byte_string(), value);
+  return finder->AddTwoByteSymbol(literal_two_byte_string());
 }
 
 void Scanner::SeekNext(size_t position) {

src/parsing/scanner.h

@@ -268,7 +268,7 @@ class Scanner {
     return false;
   }
 
-  int FindSymbol(DuplicateFinder* finder, int value);
+  bool FindSymbol(DuplicateFinder* finder);
 
   UnicodeCache* unicode_cache() { return unicode_cache_; }