src/v8/src/factory.cc

   1 // Copyright 2014 the V8 project authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "src/factory.h"
   6
   7 #include "src/allocation-site-scopes.h"
   8 #include "src/base/bits.h"
   9 #include "src/conversions.h"
  10 #include "src/isolate-inl.h"
  11 #include "src/macro-assembler.h"
  12
  13 namespace v8 {
  14 namespace internal {
  15
  16
  17 template<typename T>
  18 Handle<T> Factory::New(Handle<Map> map, AllocationSpace space) {
  19   CALL_HEAP_FUNCTION(
  20       isolate(),
  21       isolate()->heap()->Allocate(*map, space),
  22       T);
  23 }
  24
  25
  26 template<typename T>
  27 Handle<T> Factory::New(Handle<Map> map,
  28                        AllocationSpace space,
  29                        Handle<AllocationSite> allocation_site) {
  30   CALL_HEAP_FUNCTION(
  31       isolate(),
  32       isolate()->heap()->Allocate(*map, space, *allocation_site),
  33       T);
  34 }
  35
  36
  37 Handle<HeapObject> Factory::NewFillerObject(int size,
  38                                             bool double_align,
  39                                             AllocationSpace space) {
  40   CALL_HEAP_FUNCTION(
  41       isolate(),
  42       isolate()->heap()->AllocateFillerObject(size, double_align, space),
  43       HeapObject);
  44 }
  45
  46
  47 Handle<Box> Factory::NewBox(Handle<Object> value) {
  48   Handle<Box> result = Handle<Box>::cast(NewStruct(BOX_TYPE));
  49   result->set_value(*value);
  50   return result;
  51 }
  52
  53
  54 Handle<Oddball> Factory::NewOddball(Handle<Map> map,
  55                                     const char* to_string,
  56                                     Handle<Object> to_number,
  57                                     byte kind) {
  58   Handle<Oddball> oddball = New<Oddball>(map, OLD_POINTER_SPACE);
  59   Oddball::Initialize(isolate(), oddball, to_string, to_number, kind);
  60   return oddball;
  61 }
  62
  63
  64 Handle<FixedArray> Factory::NewFixedArray(int size, PretenureFlag pretenure) {
  65   DCHECK(0 <= size);
  66   CALL_HEAP_FUNCTION(
  67       isolate(),
  68       isolate()->heap()->AllocateFixedArray(size, pretenure),
  69       FixedArray);
  70 }
  71
  72
  73 Handle<FixedArray> Factory::NewFixedArrayWithHoles(int size,
  74                                                    PretenureFlag pretenure) {
  75   DCHECK(0 <= size);
  76   CALL_HEAP_FUNCTION(
  77       isolate(),
  78       isolate()->heap()->AllocateFixedArrayWithFiller(size,
  79                                                       pretenure,
  80                                                       *the_hole_value()),
  81       FixedArray);
  82 }
  83
  84
  85 Handle<FixedArray> Factory::NewUninitializedFixedArray(int size) {
  86   CALL_HEAP_FUNCTION(
  87       isolate(),
  88       isolate()->heap()->AllocateUninitializedFixedArray(size),
  89       FixedArray);
  90 }
  91
  92
  93 Handle<FixedArrayBase> Factory::NewFixedDoubleArray(int size,
  94                                                     PretenureFlag pretenure) {
  95   DCHECK(0 <= size);
  96   CALL_HEAP_FUNCTION(
  97       isolate(),
  98       isolate()->heap()->AllocateUninitializedFixedDoubleArray(size, pretenure),
  99       FixedArrayBase);
 100 }
 101
 102
 103 Handle<FixedArrayBase> Factory::NewFixedDoubleArrayWithHoles(
 104     int size,
 105     PretenureFlag pretenure) {
 106   DCHECK(0 <= size);
 107   Handle<FixedArrayBase> array = NewFixedDoubleArray(size, pretenure);
 108   if (size > 0) {
 109     Handle<FixedDoubleArray> double_array =
 110         Handle<FixedDoubleArray>::cast(array);
 111     for (int i = 0; i < size; ++i) {
 112       double_array->set_the_hole(i);
 113     }
 114   }
 115   return array;
 116 }
 117
 118
 119 Handle<ConstantPoolArray> Factory::NewConstantPoolArray(
 120     const ConstantPoolArray::NumberOfEntries& small) {
 121   DCHECK(small.total_count() > 0);
 122   CALL_HEAP_FUNCTION(
 123       isolate(),
 124       isolate()->heap()->AllocateConstantPoolArray(small),
 125       ConstantPoolArray);
 126 }
 127
 128
 129 Handle<ConstantPoolArray> Factory::NewExtendedConstantPoolArray(
 130     const ConstantPoolArray::NumberOfEntries& small,
 131     const ConstantPoolArray::NumberOfEntries& extended) {
 132   DCHECK(small.total_count() > 0);
 133   DCHECK(extended.total_count() > 0);
 134   CALL_HEAP_FUNCTION(
 135       isolate(),
 136       isolate()->heap()->AllocateExtendedConstantPoolArray(small, extended),
 137       ConstantPoolArray);
 138 }
 139
 140
 141 Handle<OrderedHashSet> Factory::NewOrderedHashSet() {
 142   return OrderedHashSet::Allocate(isolate(), 4);
 143 }
 144
 145
 146 Handle<OrderedHashMap> Factory::NewOrderedHashMap() {
 147   return OrderedHashMap::Allocate(isolate(), 4);
 148 }
 149
 150
 151 Handle<AccessorPair> Factory::NewAccessorPair() {
 152   Handle<AccessorPair> accessors =
 153       Handle<AccessorPair>::cast(NewStruct(ACCESSOR_PAIR_TYPE));
 154   accessors->set_getter(*the_hole_value(), SKIP_WRITE_BARRIER);
 155   accessors->set_setter(*the_hole_value(), SKIP_WRITE_BARRIER);
 156   return accessors;
 157 }
 158
 159
 160 Handle<TypeFeedbackInfo> Factory::NewTypeFeedbackInfo() {
 161   Handle<TypeFeedbackInfo> info =
 162       Handle<TypeFeedbackInfo>::cast(NewStruct(TYPE_FEEDBACK_INFO_TYPE));
 163   info->initialize_storage();
 164   return info;
 165 }
 166
 167
 168 // Internalized strings are created in the old generation (data space).
 169 Handle<String> Factory::InternalizeUtf8String(Vector<const char> string) {
 170   Utf8StringKey key(string, isolate()->heap()->HashSeed());
 171   return InternalizeStringWithKey(&key);
 172 }
 173
 174
 175 // Internalized strings are created in the old generation (data space).
 176 Handle<String> Factory::InternalizeString(Handle<String> string) {
 177   if (string->IsInternalizedString()) return string;
 178   return StringTable::LookupString(isolate(), string);
 179 }
 180
 181
 182 Handle<String> Factory::InternalizeOneByteString(Vector<const uint8_t> string) {
 183   OneByteStringKey key(string, isolate()->heap()->HashSeed());
 184   return InternalizeStringWithKey(&key);
 185 }
 186
 187
 188 Handle<String> Factory::InternalizeOneByteString(
 189     Handle<SeqOneByteString> string, int from, int length) {
 190   SeqOneByteSubStringKey key(string, from, length);
 191   return InternalizeStringWithKey(&key);
 192 }
 193
 194
 195 Handle<String> Factory::InternalizeTwoByteString(Vector<const uc16> string) {
 196   TwoByteStringKey key(string, isolate()->heap()->HashSeed());
 197   return InternalizeStringWithKey(&key);
 198 }
 199
 200
 201 template<class StringTableKey>
 202 Handle<String> Factory::InternalizeStringWithKey(StringTableKey* key) {
 203   return StringTable::LookupKey(isolate(), key);
 204 }
 205
 206
 207 MaybeHandle<String> Factory::NewStringFromOneByte(Vector<const uint8_t> string,
 208                                                   PretenureFlag pretenure) {
 209   int length = string.length();
 210   if (length == 1) return LookupSingleCharacterStringFromCode(string[0]);
 211   Handle<SeqOneByteString> result;
 212   ASSIGN_RETURN_ON_EXCEPTION(
 213       isolate(),
 214       result,
 215       NewRawOneByteString(string.length(), pretenure),
 216       String);
 217
 218   DisallowHeapAllocation no_gc;
 219   // Copy the characters into the new object.
 220   CopyChars(SeqOneByteString::cast(*result)->GetChars(),
 221             string.start(),
 222             length);
 223   return result;
 224 }
 225
 226 MaybeHandle<String> Factory::NewStringFromUtf8(Vector<const char> string,
 227                                                PretenureFlag pretenure) {
 228   // Check for ASCII first since this is the common case.
 229   const char* start = string.start();
 230   int length = string.length();
 231   int non_ascii_start = String::NonAsciiStart(start, length);
 232   if (non_ascii_start >= length) {
 233     // If the string is ASCII, we do not need to convert the characters
 234     // since UTF8 is backwards compatible with ASCII.
 235     return NewStringFromOneByte(Vector<const uint8_t>::cast(string), pretenure);
 236   }
 237
 238   // Non-ASCII and we need to decode.
 239   Access<UnicodeCache::Utf8Decoder>
 240       decoder(isolate()->unicode_cache()->utf8_decoder());
 241   decoder->Reset(string.start() + non_ascii_start,
 242                  length - non_ascii_start);
 243   int utf16_length = decoder->Utf16Length();
 244   DCHECK(utf16_length > 0);
 245   // Allocate string.
 246   Handle<SeqTwoByteString> result;
 247   ASSIGN_RETURN_ON_EXCEPTION(
 248       isolate(), result,
 249       NewRawTwoByteString(non_ascii_start + utf16_length, pretenure),
 250       String);
 251   // Copy ASCII portion.
 252   uint16_t* data = result->GetChars();
 253   const char* ascii_data = string.start();
 254   for (int i = 0; i < non_ascii_start; i++) {
 255     *data++ = *ascii_data++;
 256   }
 257   // Now write the remainder.
 258   decoder->WriteUtf16(data, utf16_length);
 259   return result;
 260 }
 261
 262
 263 MaybeHandle<String> Factory::NewStringFromTwoByte(Vector<const uc16> string,
 264                                                   PretenureFlag pretenure) {
 265   int length = string.length();
 266   const uc16* start = string.start();
 267   if (String::IsOneByte(start, length)) {
 268     if (length == 1) return LookupSingleCharacterStringFromCode(string[0]);
 269     Handle<SeqOneByteString> result;
 270     ASSIGN_RETURN_ON_EXCEPTION(
 271         isolate(),
 272         result,
 273         NewRawOneByteString(length, pretenure),
 274         String);
 275     CopyChars(result->GetChars(), start, length);
 276     return result;
 277   } else {
 278     Handle<SeqTwoByteString> result;
 279     ASSIGN_RETURN_ON_EXCEPTION(
 280         isolate(),
 281         result,
 282         NewRawTwoByteString(length, pretenure),
 283         String);
 284     CopyChars(result->GetChars(), start, length);
 285     return result;
 286   }
 287 }
 288
 289
 290 Handle<String> Factory::NewInternalizedStringFromUtf8(Vector<const char> str,
 291                                                       int chars,
 292                                                       uint32_t hash_field) {
 293   CALL_HEAP_FUNCTION(
 294       isolate(),
 295       isolate()->heap()->AllocateInternalizedStringFromUtf8(
 296           str, chars, hash_field),
 297       String);
 298 }
 299
 300
 301 MUST_USE_RESULT Handle<String> Factory::NewOneByteInternalizedString(
 302       Vector<const uint8_t> str,
 303       uint32_t hash_field) {
 304   CALL_HEAP_FUNCTION(
 305       isolate(),
 306       isolate()->heap()->AllocateOneByteInternalizedString(str, hash_field),
 307       String);
 308 }
 309
 310
 311 MUST_USE_RESULT Handle<String> Factory::NewOneByteInternalizedSubString(
 312     Handle<SeqOneByteString> string, int offset, int length,
 313     uint32_t hash_field) {
 314   CALL_HEAP_FUNCTION(
 315       isolate(), isolate()->heap()->AllocateOneByteInternalizedString(
 316                      Vector<const uint8_t>(string->GetChars() + offset, length),
 317                      hash_field),
 318       String);
 319 }
 320
 321
 322 MUST_USE_RESULT Handle<String> Factory::NewTwoByteInternalizedString(
 323       Vector<const uc16> str,
 324       uint32_t hash_field) {
 325   CALL_HEAP_FUNCTION(
 326       isolate(),
 327       isolate()->heap()->AllocateTwoByteInternalizedString(str, hash_field),
 328       String);
 329 }
 330
 331
 332 Handle<String> Factory::NewInternalizedStringImpl(
 333     Handle<String> string, int chars, uint32_t hash_field) {
 334   CALL_HEAP_FUNCTION(
 335       isolate(),
 336       isolate()->heap()->AllocateInternalizedStringImpl(
 337           *string, chars, hash_field),
 338       String);
 339 }
 340
 341
 342 MaybeHandle<Map> Factory::InternalizedStringMapForString(
 343     Handle<String> string) {
 344   // If the string is in new space it cannot be used as internalized.
 345   if (isolate()->heap()->InNewSpace(*string)) return MaybeHandle<Map>();
 346
 347   // Find the corresponding internalized string map for strings.
 348   switch (string->map()->instance_type()) {
 349     case STRING_TYPE: return internalized_string_map();
 350     case ONE_BYTE_STRING_TYPE:
 351       return one_byte_internalized_string_map();
 352     case EXTERNAL_STRING_TYPE: return external_internalized_string_map();
 353     case EXTERNAL_ONE_BYTE_STRING_TYPE:
 354       return external_one_byte_internalized_string_map();
 355     case EXTERNAL_STRING_WITH_ONE_BYTE_DATA_TYPE:
 356       return external_internalized_string_with_one_byte_data_map();
 357     case SHORT_EXTERNAL_STRING_TYPE:
 358       return short_external_internalized_string_map();
 359     case SHORT_EXTERNAL_ONE_BYTE_STRING_TYPE:
 360       return short_external_one_byte_internalized_string_map();
 361     case SHORT_EXTERNAL_STRING_WITH_ONE_BYTE_DATA_TYPE:
 362       return short_external_internalized_string_with_one_byte_data_map();
 363     default: return MaybeHandle<Map>();  // No match found.
 364   }
 365 }
 366
 367
 368 MaybeHandle<SeqOneByteString> Factory::NewRawOneByteString(
 369     int length, PretenureFlag pretenure) {
 370   if (length > String::kMaxLength || length < 0) {
 371     THROW_NEW_ERROR(isolate(), NewInvalidStringLengthError(), SeqOneByteString);
 372   }
 373   CALL_HEAP_FUNCTION(
 374       isolate(),
 375       isolate()->heap()->AllocateRawOneByteString(length, pretenure),
 376       SeqOneByteString);
 377 }
 378
 379
 380 MaybeHandle<SeqTwoByteString> Factory::NewRawTwoByteString(
 381     int length, PretenureFlag pretenure) {
 382   if (length > String::kMaxLength || length < 0) {
 383     THROW_NEW_ERROR(isolate(), NewInvalidStringLengthError(), SeqTwoByteString);
 384   }
 385   CALL_HEAP_FUNCTION(
 386       isolate(),
 387       isolate()->heap()->AllocateRawTwoByteString(length, pretenure),
 388       SeqTwoByteString);
 389 }
 390
 391
 392 Handle<String> Factory::LookupSingleCharacterStringFromCode(uint32_t code) {
 393   if (code <= String::kMaxOneByteCharCodeU) {
 394     {
 395       DisallowHeapAllocation no_allocation;
 396       Object* value = single_character_string_cache()->get(code);
 397       if (value != *undefined_value()) {
 398         return handle(String::cast(value), isolate());
 399       }
 400     }
 401     uint8_t buffer[1];
 402     buffer[0] = static_cast<uint8_t>(code);
 403     Handle<String> result =
 404         InternalizeOneByteString(Vector<const uint8_t>(buffer, 1));
 405     single_character_string_cache()->set(code, *result);
 406     return result;
 407   }
 408   DCHECK(code <= String::kMaxUtf16CodeUnitU);
 409
 410   Handle<SeqTwoByteString> result = NewRawTwoByteString(1).ToHandleChecked();
 411   result->SeqTwoByteStringSet(0, static_cast<uint16_t>(code));
 412   return result;
 413 }
 414
 415
 416 // Returns true for a character in a range.  Both limits are inclusive.
 417 static inline bool Between(uint32_t character, uint32_t from, uint32_t to) {
 418   // This makes uses of the the unsigned wraparound.
 419   return character - from <= to - from;
 420 }
 421
 422
 423 static inline Handle<String> MakeOrFindTwoCharacterString(Isolate* isolate,
 424                                                           uint16_t c1,
 425                                                           uint16_t c2) {
 426   // Numeric strings have a different hash algorithm not known by
 427   // LookupTwoCharsStringIfExists, so we skip this step for such strings.
 428   if (!Between(c1, '0', '9') || !Between(c2, '0', '9')) {
 429     Handle<String> result;
 430     if (StringTable::LookupTwoCharsStringIfExists(isolate, c1, c2).
 431         ToHandle(&result)) {
 432       return result;
 433     }
 434   }
 435
 436   // Now we know the length is 2, we might as well make use of that fact
 437   // when building the new string.
 438   if (static_cast<unsigned>(c1 | c2) <= String::kMaxOneByteCharCodeU) {
 439     // We can do this.
 440     DCHECK(base::bits::IsPowerOfTwo32(String::kMaxOneByteCharCodeU +
 441                                       1));  // because of this.
 442     Handle<SeqOneByteString> str =
 443         isolate->factory()->NewRawOneByteString(2).ToHandleChecked();
 444     uint8_t* dest = str->GetChars();
 445     dest[0] = static_cast<uint8_t>(c1);
 446     dest[1] = static_cast<uint8_t>(c2);
 447     return str;
 448   } else {
 449     Handle<SeqTwoByteString> str =
 450         isolate->factory()->NewRawTwoByteString(2).ToHandleChecked();
 451     uc16* dest = str->GetChars();
 452     dest[0] = c1;
 453     dest[1] = c2;
 454     return str;
 455   }
 456 }
 457
 458
 459 template<typename SinkChar, typename StringType>
 460 Handle<String> ConcatStringContent(Handle<StringType> result,
 461                                    Handle<String> first,
 462                                    Handle<String> second) {
 463   DisallowHeapAllocation pointer_stays_valid;
 464   SinkChar* sink = result->GetChars();
 465   String::WriteToFlat(*first, sink, 0, first->length());
 466   String::WriteToFlat(*second, sink + first->length(), 0, second->length());
 467   return result;
 468 }
 469
 470
 471 MaybeHandle<String> Factory::NewConsString(Handle<String> left,
 472                                            Handle<String> right) {
 473   int left_length = left->length();
 474   if (left_length == 0) return right;
 475   int right_length = right->length();
 476   if (right_length == 0) return left;
 477
 478   int length = left_length + right_length;
 479
 480   if (length == 2) {
 481     uint16_t c1 = left->Get(0);
 482     uint16_t c2 = right->Get(0);
 483     return MakeOrFindTwoCharacterString(isolate(), c1, c2);
 484   }
 485
 486   // Make sure that an out of memory exception is thrown if the length
 487   // of the new cons string is too large.
 488   if (length > String::kMaxLength || length < 0) {
 489     THROW_NEW_ERROR(isolate(), NewInvalidStringLengthError(), String);
 490   }
 491
 492   bool left_is_one_byte = left->IsOneByteRepresentation();
 493   bool right_is_one_byte = right->IsOneByteRepresentation();
 494   bool is_one_byte = left_is_one_byte && right_is_one_byte;
 495   bool is_one_byte_data_in_two_byte_string = false;
 496   if (!is_one_byte) {
 497     // At least one of the strings uses two-byte representation so we
 498     // can't use the fast case code for short one-byte strings below, but
 499     // we can try to save memory if all chars actually fit in one-byte.
 500     is_one_byte_data_in_two_byte_string =
 501         left->HasOnlyOneByteChars() && right->HasOnlyOneByteChars();
 502     if (is_one_byte_data_in_two_byte_string) {
 503       isolate()->counters()->string_add_runtime_ext_to_one_byte()->Increment();
 504     }
 505   }
 506
 507   // If the resulting string is small make a flat string.
 508   if (length < ConsString::kMinLength) {
 509     // Note that neither of the two inputs can be a slice because:
 510     STATIC_ASSERT(ConsString::kMinLength <= SlicedString::kMinLength);
 511     DCHECK(left->IsFlat());
 512     DCHECK(right->IsFlat());
 513
 514     STATIC_ASSERT(ConsString::kMinLength <= String::kMaxLength);
 515     if (is_one_byte) {
 516       Handle<SeqOneByteString> result =
 517           NewRawOneByteString(length).ToHandleChecked();
 518       DisallowHeapAllocation no_gc;
 519       uint8_t* dest = result->GetChars();
 520       // Copy left part.
 521       const uint8_t* src =
 522           left->IsExternalString()
 523               ? Handle<ExternalOneByteString>::cast(left)->GetChars()
 524               : Handle<SeqOneByteString>::cast(left)->GetChars();
 525       for (int i = 0; i < left_length; i++) *dest++ = src[i];
 526       // Copy right part.
 527       src = right->IsExternalString()
 528                 ? Handle<ExternalOneByteString>::cast(right)->GetChars()
 529                 : Handle<SeqOneByteString>::cast(right)->GetChars();
 530       for (int i = 0; i < right_length; i++) *dest++ = src[i];
 531       return result;
 532     }
 533
 534     return (is_one_byte_data_in_two_byte_string)
 535         ? ConcatStringContent<uint8_t>(
 536             NewRawOneByteString(length).ToHandleChecked(), left, right)
 537         : ConcatStringContent<uc16>(
 538             NewRawTwoByteString(length).ToHandleChecked(), left, right);
 539   }
 540
 541   Handle<Map> map = (is_one_byte || is_one_byte_data_in_two_byte_string)
 542                         ? cons_one_byte_string_map()
 543                         : cons_string_map();
 544   Handle<ConsString> result =  New<ConsString>(map, NEW_SPACE);
 545
 546   DisallowHeapAllocation no_gc;
 547   WriteBarrierMode mode = result->GetWriteBarrierMode(no_gc);
 548
 549   result->set_hash_field(String::kEmptyHashField);
 550   result->set_length(length);
 551   result->set_first(*left, mode);
 552   result->set_second(*right, mode);
 553   return result;
 554 }
 555
 556
 557 Handle<String> Factory::NewProperSubString(Handle<String> str,
 558                                            int begin,
 559                                            int end) {
 560 #if VERIFY_HEAP
 561   if (FLAG_verify_heap) str->StringVerify();
 562 #endif
 563   DCHECK(begin > 0 || end < str->length());
 564
 565   str = String::Flatten(str);
 566
 567   int length = end - begin;
 568   if (length <= 0) return empty_string();
 569   if (length == 1) {
 570     return LookupSingleCharacterStringFromCode(str->Get(begin));
 571   }
 572   if (length == 2) {
 573     // Optimization for 2-byte strings often used as keys in a decompression
 574     // dictionary.  Check whether we already have the string in the string
 575     // table to prevent creation of many unnecessary strings.
 576     uint16_t c1 = str->Get(begin);
 577     uint16_t c2 = str->Get(begin + 1);
 578     return MakeOrFindTwoCharacterString(isolate(), c1, c2);
 579   }
 580
 581   if (!FLAG_string_slices || length < SlicedString::kMinLength) {
 582     if (str->IsOneByteRepresentation()) {
 583       Handle<SeqOneByteString> result =
 584           NewRawOneByteString(length).ToHandleChecked();
 585       uint8_t* dest = result->GetChars();
 586       DisallowHeapAllocation no_gc;
 587       String::WriteToFlat(*str, dest, begin, end);
 588       return result;
 589     } else {
 590       Handle<SeqTwoByteString> result =
 591           NewRawTwoByteString(length).ToHandleChecked();
 592       uc16* dest = result->GetChars();
 593       DisallowHeapAllocation no_gc;
 594       String::WriteToFlat(*str, dest, begin, end);
 595       return result;
 596     }
 597   }
 598
 599   int offset = begin;
 600
 601   if (str->IsSlicedString()) {
 602     Handle<SlicedString> slice = Handle<SlicedString>::cast(str);
 603     str = Handle<String>(slice->parent(), isolate());
 604     offset += slice->offset();
 605   }
 606
 607   DCHECK(str->IsSeqString() || str->IsExternalString());
 608   Handle<Map> map = str->IsOneByteRepresentation()
 609                         ? sliced_one_byte_string_map()
 610                         : sliced_string_map();
 611   Handle<SlicedString> slice = New<SlicedString>(map, NEW_SPACE);
 612
 613   slice->set_hash_field(String::kEmptyHashField);
 614   slice->set_length(length);
 615   slice->set_parent(*str);
 616   slice->set_offset(offset);
 617   return slice;
 618 }
 619
 620
 621 MaybeHandle<String> Factory::NewExternalStringFromOneByte(
 622     const ExternalOneByteString::Resource* resource) {
 623   size_t length = resource->length();
 624   if (length > static_cast<size_t>(String::kMaxLength)) {
 625     THROW_NEW_ERROR(isolate(), NewInvalidStringLengthError(), String);
 626   }
 627
 628   Handle<Map> map = external_one_byte_string_map();
 629   Handle<ExternalOneByteString> external_string =
 630       New<ExternalOneByteString>(map, NEW_SPACE);
 631   external_string->set_length(static_cast<int>(length));
 632   external_string->set_hash_field(String::kEmptyHashField);
 633   external_string->set_resource(resource);
 634
 635   return external_string;
 636 }
 637
 638
 639 MaybeHandle<String> Factory::NewExternalStringFromTwoByte(
 640     const ExternalTwoByteString::Resource* resource) {
 641   size_t length = resource->length();
 642   if (length > static_cast<size_t>(String::kMaxLength)) {
 643     THROW_NEW_ERROR(isolate(), NewInvalidStringLengthError(), String);
 644   }
 645
 646   // For small strings we check whether the resource contains only
 647   // one byte characters.  If yes, we use a different string map.
 648   static const size_t kOneByteCheckLengthLimit = 32;
 649   bool is_one_byte = length <= kOneByteCheckLengthLimit &&
 650       String::IsOneByte(resource->data(), static_cast<int>(length));
 651   Handle<Map> map = is_one_byte ?
 652       external_string_with_one_byte_data_map() : external_string_map();
 653   Handle<ExternalTwoByteString> external_string =
 654       New<ExternalTwoByteString>(map, NEW_SPACE);
 655   external_string->set_length(static_cast<int>(length));
 656   external_string->set_hash_field(String::kEmptyHashField);
 657   external_string->set_resource(resource);
 658
 659   return external_string;
 660 }
 661
 662
 663 Handle<Symbol> Factory::NewSymbol() {
 664   CALL_HEAP_FUNCTION(
 665       isolate(),
 666       isolate()->heap()->AllocateSymbol(),
 667       Symbol);
 668 }
 669
 670
 671 Handle<Symbol> Factory::NewPrivateSymbol() {
 672   Handle<Symbol> symbol = NewSymbol();
 673   symbol->set_is_private(true);
 674   return symbol;
 675 }
 676
 677
 678 Handle<Symbol> Factory::NewPrivateOwnSymbol() {
 679   Handle<Symbol> symbol = NewSymbol();
 680   symbol->set_is_private(true);
 681   symbol->set_is_own(true);
 682   return symbol;
 683 }
 684
 685
 686 Handle<Context> Factory::NewNativeContext() {
 687   Handle<FixedArray> array = NewFixedArray(Context::NATIVE_CONTEXT_SLOTS);
 688   array->set_map_no_write_barrier(*native_context_map());
 689   Handle<Context> context = Handle<Context>::cast(array);
 690   context->set_js_array_maps(*undefined_value());
 691   DCHECK(context->IsNativeContext());
 692   return context;
 693 }
 694
 695
 696 Handle<Context> Factory::NewGlobalContext(Handle<JSFunction> function,
 697                                           Handle<ScopeInfo> scope_info) {
 698   Handle<FixedArray> array =
 699       NewFixedArray(scope_info->ContextLength(), TENURED);
 700   array->set_map_no_write_barrier(*global_context_map());
 701   Handle<Context> context = Handle<Context>::cast(array);
 702   context->set_closure(*function);
 703   context->set_previous(function->context());
 704   context->set_extension(*scope_info);
 705   context->set_global_object(function->context()->global_object());
 706   DCHECK(context->IsGlobalContext());
 707   return context;
 708 }
 709
 710
 711 Handle<Context> Factory::NewModuleContext(Handle<ScopeInfo> scope_info) {
 712   Handle<FixedArray> array =
 713       NewFixedArray(scope_info->ContextLength(), TENURED);
 714   array->set_map_no_write_barrier(*module_context_map());
 715   // Instance link will be set later.
 716   Handle<Context> context = Handle<Context>::cast(array);
 717   context->set_extension(Smi::FromInt(0));
 718   return context;
 719 }
 720
 721
 722 Handle<Context> Factory::NewFunctionContext(int length,
 723                                             Handle<JSFunction> function) {
 724   DCHECK(length >= Context::MIN_CONTEXT_SLOTS);
 725   Handle<FixedArray> array = NewFixedArray(length);
 726   array->set_map_no_write_barrier(*function_context_map());
 727   Handle<Context> context = Handle<Context>::cast(array);
 728   context->set_closure(*function);
 729   context->set_previous(function->context());
 730   context->set_extension(Smi::FromInt(0));
 731   context->set_global_object(function->context()->global_object());
 732   return context;
 733 }
 734
 735
 736 Handle<Context> Factory::NewCatchContext(Handle<JSFunction> function,
 737                                          Handle<Context> previous,
 738                                          Handle<String> name,
 739                                          Handle<Object> thrown_object) {
 740   STATIC_ASSERT(Context::MIN_CONTEXT_SLOTS == Context::THROWN_OBJECT_INDEX);
 741   Handle<FixedArray> array = NewFixedArray(Context::MIN_CONTEXT_SLOTS + 1);
 742   array->set_map_no_write_barrier(*catch_context_map());
 743   Handle<Context> context = Handle<Context>::cast(array);
 744   context->set_closure(*function);
 745   context->set_previous(*previous);
 746   context->set_extension(*name);
 747   context->set_global_object(previous->global_object());
 748   context->set(Context::THROWN_OBJECT_INDEX, *thrown_object);
 749   return context;
 750 }
 751
 752
 753 Handle<Context> Factory::NewWithContext(Handle<JSFunction> function,
 754                                         Handle<Context> previous,
 755                                         Handle<JSReceiver> extension) {
 756   Handle<FixedArray> array = NewFixedArray(Context::MIN_CONTEXT_SLOTS);
 757   array->set_map_no_write_barrier(*with_context_map());
 758   Handle<Context> context = Handle<Context>::cast(array);
 759   context->set_closure(*function);
 760   context->set_previous(*previous);
 761   context->set_extension(*extension);
 762   context->set_global_object(previous->global_object());
 763   return context;
 764 }
 765
 766
 767 Handle<Context> Factory::NewBlockContext(Handle<JSFunction> function,
 768                                          Handle<Context> previous,
 769                                          Handle<ScopeInfo> scope_info) {
 770   Handle<FixedArray> array =
 771       NewFixedArrayWithHoles(scope_info->ContextLength());
 772   array->set_map_no_write_barrier(*block_context_map());
 773   Handle<Context> context = Handle<Context>::cast(array);
 774   context->set_closure(*function);
 775   context->set_previous(*previous);
 776   context->set_extension(*scope_info);
 777   context->set_global_object(previous->global_object());
 778   return context;
 779 }
 780
 781
 782 Handle<Struct> Factory::NewStruct(InstanceType type) {
 783   CALL_HEAP_FUNCTION(
 784       isolate(),
 785       isolate()->heap()->AllocateStruct(type),
 786       Struct);
 787 }
 788
 789
 790 Handle<CodeCache> Factory::NewCodeCache() {
 791   Handle<CodeCache> code_cache =
 792       Handle<CodeCache>::cast(NewStruct(CODE_CACHE_TYPE));
 793   code_cache->set_default_cache(*empty_fixed_array(), SKIP_WRITE_BARRIER);
 794   code_cache->set_normal_type_cache(*undefined_value(), SKIP_WRITE_BARRIER);
 795   return code_cache;
 796 }
 797
 798
 799 Handle<AliasedArgumentsEntry> Factory::NewAliasedArgumentsEntry(
 800     int aliased_context_slot) {
 801   Handle<AliasedArgumentsEntry> entry = Handle<AliasedArgumentsEntry>::cast(
 802       NewStruct(ALIASED_ARGUMENTS_ENTRY_TYPE));
 803   entry->set_aliased_context_slot(aliased_context_slot);
 804   return entry;
 805 }
 806
 807
 808 Handle<DeclaredAccessorDescriptor> Factory::NewDeclaredAccessorDescriptor() {
 809   return Handle<DeclaredAccessorDescriptor>::cast(
 810       NewStruct(DECLARED_ACCESSOR_DESCRIPTOR_TYPE));
 811 }
 812
 813
 814 Handle<DeclaredAccessorInfo> Factory::NewDeclaredAccessorInfo() {
 815   Handle<DeclaredAccessorInfo> info =
 816       Handle<DeclaredAccessorInfo>::cast(
 817           NewStruct(DECLARED_ACCESSOR_INFO_TYPE));
 818   info->set_flag(0);  // Must clear the flag, it was initialized as undefined.
 819   return info;
 820 }
 821
 822
 823 Handle<ExecutableAccessorInfo> Factory::NewExecutableAccessorInfo() {
 824   Handle<ExecutableAccessorInfo> info =
 825       Handle<ExecutableAccessorInfo>::cast(
 826           NewStruct(EXECUTABLE_ACCESSOR_INFO_TYPE));
 827   info->set_flag(0);  // Must clear the flag, it was initialized as undefined.
 828   return info;
 829 }
 830
 831
 832 Handle<Script> Factory::NewScript(Handle<String> source) {
 833   // Generate id for this script.
 834   Heap* heap = isolate()->heap();
 835   int id = heap->last_script_id()->value() + 1;
 836   if (!Smi::IsValid(id) || id < 0) id = 1;
 837   heap->set_last_script_id(Smi::FromInt(id));
 838
 839   // Create and initialize script object.
 840   Handle<Foreign> wrapper = NewForeign(0, TENURED);
 841   Handle<Script> script = Handle<Script>::cast(NewStruct(SCRIPT_TYPE));
 842   script->set_source(*source);
 843   script->set_name(heap->undefined_value());
 844   script->set_id(Smi::FromInt(id));
 845   script->set_line_offset(Smi::FromInt(0));
 846   script->set_column_offset(Smi::FromInt(0));
 847   script->set_context_data(heap->undefined_value());
 848   script->set_type(Smi::FromInt(Script::TYPE_NORMAL));
 849   script->set_wrapper(*wrapper);
 850   script->set_line_ends(heap->undefined_value());
 851   script->set_eval_from_shared(heap->undefined_value());
 852   script->set_eval_from_instructions_offset(Smi::FromInt(0));
 853   script->set_flags(Smi::FromInt(0));
 854
 855   return script;
 856 }
 857
 858
 859 Handle<Foreign> Factory::NewForeign(Address addr, PretenureFlag pretenure) {
 860   CALL_HEAP_FUNCTION(isolate(),
 861                      isolate()->heap()->AllocateForeign(addr, pretenure),
 862                      Foreign);
 863 }
 864
 865
 866 Handle<Foreign> Factory::NewForeign(const AccessorDescriptor* desc) {
 867   return NewForeign((Address) desc, TENURED);
 868 }
 869
 870
 871 Handle<ByteArray> Factory::NewByteArray(int length, PretenureFlag pretenure) {
 872   DCHECK(0 <= length);
 873   CALL_HEAP_FUNCTION(
 874       isolate(),
 875       isolate()->heap()->AllocateByteArray(length, pretenure),
 876       ByteArray);
 877 }
 878
 879
 880 Handle<ExternalArray> Factory::NewExternalArray(int length,
 881                                                 ExternalArrayType array_type,
 882                                                 void* external_pointer,
 883                                                 PretenureFlag pretenure) {
 884   DCHECK(0 <= length && length <= Smi::kMaxValue);
 885   CALL_HEAP_FUNCTION(
 886       isolate(),
 887       isolate()->heap()->AllocateExternalArray(length,
 888                                                array_type,
 889                                                external_pointer,
 890                                                pretenure),
 891       ExternalArray);
 892 }
 893
 894
 895 Handle<FixedTypedArrayBase> Factory::NewFixedTypedArray(
 896     int length,
 897     ExternalArrayType array_type,
 898     PretenureFlag pretenure) {
 899   DCHECK(0 <= length && length <= Smi::kMaxValue);
 900   CALL_HEAP_FUNCTION(
 901       isolate(),
 902       isolate()->heap()->AllocateFixedTypedArray(length,
 903                                                  array_type,
 904                                                  pretenure),
 905       FixedTypedArrayBase);
 906 }
 907
 908
 909 Handle<Cell> Factory::NewCell(Handle<Object> value) {
 910   AllowDeferredHandleDereference convert_to_cell;
 911   CALL_HEAP_FUNCTION(
 912       isolate(),
 913       isolate()->heap()->AllocateCell(*value),
 914       Cell);
 915 }
 916
 917
 918 Handle<PropertyCell> Factory::NewPropertyCellWithHole() {
 919   CALL_HEAP_FUNCTION(
 920       isolate(),
 921       isolate()->heap()->AllocatePropertyCell(),
 922       PropertyCell);
 923 }
 924
 925
 926 Handle<PropertyCell> Factory::NewPropertyCell(Handle<Object> value) {
 927   AllowDeferredHandleDereference convert_to_cell;
 928   Handle<PropertyCell> cell = NewPropertyCellWithHole();
 929   PropertyCell::SetValueInferType(cell, value);
 930   return cell;
 931 }
 932
 933
 934 Handle<AllocationSite> Factory::NewAllocationSite() {
 935   Handle<Map> map = allocation_site_map();
 936   Handle<AllocationSite> site = New<AllocationSite>(map, OLD_POINTER_SPACE);
 937   site->Initialize();
 938
 939   // Link the site
 940   site->set_weak_next(isolate()->heap()->allocation_sites_list());
 941   isolate()->heap()->set_allocation_sites_list(*site);
 942   return site;
 943 }
 944
 945
 946 Handle<Map> Factory::NewMap(InstanceType type,
 947                             int instance_size,
 948                             ElementsKind elements_kind) {
 949   CALL_HEAP_FUNCTION(
 950       isolate(),
 951       isolate()->heap()->AllocateMap(type, instance_size, elements_kind),
 952       Map);
 953 }
 954
 955
 956 Handle<JSObject> Factory::CopyJSObject(Handle<JSObject> object) {
 957   CALL_HEAP_FUNCTION(isolate(),
 958                      isolate()->heap()->CopyJSObject(*object, NULL),
 959                      JSObject);
 960 }
 961
 962
 963 Handle<JSObject> Factory::CopyJSObjectWithAllocationSite(
 964     Handle<JSObject> object,
 965     Handle<AllocationSite> site) {
 966   CALL_HEAP_FUNCTION(isolate(),
 967                      isolate()->heap()->CopyJSObject(
 968                          *object,
 969                          site.is_null() ? NULL : *site),
 970                      JSObject);
 971 }
 972
 973
 974 Handle<FixedArray> Factory::CopyFixedArrayWithMap(Handle<FixedArray> array,
 975                                                   Handle<Map> map) {
 976   CALL_HEAP_FUNCTION(isolate(),
 977                      isolate()->heap()->CopyFixedArrayWithMap(*array, *map),
 978                      FixedArray);
 979 }
 980
 981
 982 Handle<FixedArray> Factory::CopyFixedArray(Handle<FixedArray> array) {
 983   CALL_HEAP_FUNCTION(isolate(),
 984                      isolate()->heap()->CopyFixedArray(*array),
 985                      FixedArray);
 986 }
 987
 988
 989 Handle<FixedArray> Factory::CopyAndTenureFixedCOWArray(
 990     Handle<FixedArray> array) {
 991   DCHECK(isolate()->heap()->InNewSpace(*array));
 992   CALL_HEAP_FUNCTION(isolate(),
 993                      isolate()->heap()->CopyAndTenureFixedCOWArray(*array),
 994                      FixedArray);
 995 }
 996
 997
 998 Handle<FixedDoubleArray> Factory::CopyFixedDoubleArray(
 999     Handle<FixedDoubleArray> array) {
1000   CALL_HEAP_FUNCTION(isolate(),
1001                      isolate()->heap()->CopyFixedDoubleArray(*array),
1002                      FixedDoubleArray);
1003 }
1004
1005
1006 Handle<ConstantPoolArray> Factory::CopyConstantPoolArray(
1007     Handle<ConstantPoolArray> array) {
1008   CALL_HEAP_FUNCTION(isolate(),
1009                      isolate()->heap()->CopyConstantPoolArray(*array),
1010                      ConstantPoolArray);
1011 }
1012
1013
1014 Handle<Object> Factory::NewNumber(double value,
1015                                   PretenureFlag pretenure) {
1016   // We need to distinguish the minus zero value and this cannot be
1017   // done after conversion to int. Doing this by comparing bit
1018   // patterns is faster than using fpclassify() et al.
1019   if (IsMinusZero(value)) return NewHeapNumber(-0.0, IMMUTABLE, pretenure);
1020
1021   int int_value = FastD2I(value);
1022   if (value == int_value && Smi::IsValid(int_value)) {
1023     return handle(Smi::FromInt(int_value), isolate());
1024   }
1025
1026   // Materialize the value in the heap.
1027   return NewHeapNumber(value, IMMUTABLE, pretenure);
1028 }
1029
1030
1031 Handle<Object> Factory::NewNumberFromInt(int32_t value,
1032                                          PretenureFlag pretenure) {
1033   if (Smi::IsValid(value)) return handle(Smi::FromInt(value), isolate());
1034   // Bypass NewNumber to avoid various redundant checks.
1035   return NewHeapNumber(FastI2D(value), IMMUTABLE, pretenure);
1036 }
1037
1038
1039 Handle<Object> Factory::NewNumberFromUint(uint32_t value,
1040                                           PretenureFlag pretenure) {
1041   int32_t int32v = static_cast<int32_t>(value);
1042   if (int32v >= 0 && Smi::IsValid(int32v)) {
1043     return handle(Smi::FromInt(int32v), isolate());
1044   }
1045   return NewHeapNumber(FastUI2D(value), IMMUTABLE, pretenure);
1046 }
1047
1048
1049 Handle<HeapNumber> Factory::NewHeapNumber(double value,
1050                                           MutableMode mode,
1051                                           PretenureFlag pretenure) {
1052   CALL_HEAP_FUNCTION(
1053       isolate(),
1054       isolate()->heap()->AllocateHeapNumber(value, mode, pretenure),
1055       HeapNumber);
1056 }
1057
1058
1059 MaybeHandle<Object> Factory::NewTypeError(const char* message,
1060                                           Vector<Handle<Object> > args) {
1061   return NewError("MakeTypeError", message, args);
1062 }
1063
1064
1065 MaybeHandle<Object> Factory::NewTypeError(Handle<String> message) {
1066   return NewError("$TypeError", message);
1067 }
1068
1069
1070 MaybeHandle<Object> Factory::NewRangeError(const char* message,
1071                                            Vector<Handle<Object> > args) {
1072   return NewError("MakeRangeError", message, args);
1073 }
1074
1075
1076 MaybeHandle<Object> Factory::NewRangeError(Handle<String> message) {
1077   return NewError("$RangeError", message);
1078 }
1079
1080
1081 MaybeHandle<Object> Factory::NewSyntaxError(const char* message,
1082                                             Handle<JSArray> args) {
1083   return NewError("MakeSyntaxError", message, args);
1084 }
1085
1086
1087 MaybeHandle<Object> Factory::NewSyntaxError(Handle<String> message) {
1088   return NewError("$SyntaxError", message);
1089 }
1090
1091
1092 MaybeHandle<Object> Factory::NewReferenceError(const char* message,
1093                                                Vector<Handle<Object> > args) {
1094   return NewError("MakeReferenceError", message, args);
1095 }
1096
1097
1098 MaybeHandle<Object> Factory::NewReferenceError(const char* message,
1099                                                Handle<JSArray> args) {
1100   return NewError("MakeReferenceError", message, args);
1101 }
1102
1103
1104 MaybeHandle<Object> Factory::NewReferenceError(Handle<String> message) {
1105   return NewError("$ReferenceError", message);
1106 }
1107
1108
1109 MaybeHandle<Object> Factory::NewError(const char* maker, const char* message,
1110                                       Vector<Handle<Object> > args) {
1111   // Instantiate a closeable HandleScope for EscapeFrom.
1112   v8::EscapableHandleScope scope(reinterpret_cast<v8::Isolate*>(isolate()));
1113   Handle<FixedArray> array = NewFixedArray(args.length());
1114   for (int i = 0; i < args.length(); i++) {
1115     array->set(i, *args[i]);
1116   }
1117   Handle<JSArray> object = NewJSArrayWithElements(array);
1118   Handle<Object> result;
1119   ASSIGN_RETURN_ON_EXCEPTION(isolate(), result,
1120                              NewError(maker, message, object), Object);
1121   return result.EscapeFrom(&scope);
1122 }
1123
1124
1125 MaybeHandle<Object> Factory::NewEvalError(const char* message,
1126                                           Vector<Handle<Object> > args) {
1127   return NewError("MakeEvalError", message, args);
1128 }
1129
1130
1131 MaybeHandle<Object> Factory::NewError(const char* message,
1132                                       Vector<Handle<Object> > args) {
1133   return NewError("MakeError", message, args);
1134 }
1135
1136
1137 Handle<String> Factory::EmergencyNewError(const char* message,
1138                                           Handle<JSArray> args) {
1139   const int kBufferSize = 1000;
1140   char buffer[kBufferSize];
1141   size_t space = kBufferSize;
1142   char* p = &buffer[0];
1143
1144   Vector<char> v(buffer, kBufferSize);
1145   StrNCpy(v, message, space);
1146   space -= Min(space, strlen(message));
1147   p = &buffer[kBufferSize] - space;
1148
1149   for (int i = 0; i < Smi::cast(args->length())->value(); i++) {
1150     if (space > 0) {
1151       *p++ = ' ';
1152       space--;
1153       if (space > 0) {
1154         Handle<String> arg_str = Handle<String>::cast(
1155             Object::GetElement(isolate(), args, i).ToHandleChecked());
1156         SmartArrayPointer<char> arg = arg_str->ToCString();
1157         Vector<char> v2(p, static_cast<int>(space));
1158         StrNCpy(v2, arg.get(), space);
1159         space -= Min(space, strlen(arg.get()));
1160         p = &buffer[kBufferSize] - space;
1161       }
1162     }
1163   }
1164   if (space > 0) {
1165     *p = '\0';
1166   } else {
1167     buffer[kBufferSize - 1] = '\0';
1168   }
1169   return NewStringFromUtf8(CStrVector(buffer), TENURED).ToHandleChecked();
1170 }
1171
1172
1173 MaybeHandle<Object> Factory::NewError(const char* maker, const char* message,
1174                                       Handle<JSArray> args) {
1175   Handle<String> make_str = InternalizeUtf8String(maker);
1176   Handle<Object> fun_obj = Object::GetProperty(
1177       isolate()->js_builtins_object(), make_str).ToHandleChecked();
1178   // If the builtins haven't been properly configured yet this error
1179   // constructor may not have been defined.  Bail out.
1180   if (!fun_obj->IsJSFunction()) {
1181     return EmergencyNewError(message, args);
1182   }
1183   Handle<JSFunction> fun = Handle<JSFunction>::cast(fun_obj);
1184   Handle<Object> message_obj = InternalizeUtf8String(message);
1185   Handle<Object> argv[] = { message_obj, args };
1186
1187   // Invoke the JavaScript factory method. If an exception is thrown while
1188   // running the factory method, use the exception as the result.
1189   Handle<Object> result;
1190   MaybeHandle<Object> exception;
1191   if (!Execution::TryCall(fun,
1192                           isolate()->js_builtins_object(),
1193                           arraysize(argv),
1194                           argv,
1195                           &exception).ToHandle(&result)) {
1196     return exception;
1197   }
1198   return result;
1199 }
1200
1201
1202 MaybeHandle<Object> Factory::NewError(Handle<String> message) {
1203   return NewError("$Error", message);
1204 }
1205
1206
1207 MaybeHandle<Object> Factory::NewError(const char* constructor,
1208                                       Handle<String> message) {
1209   Handle<String> constr = InternalizeUtf8String(constructor);
1210   Handle<JSFunction> fun = Handle<JSFunction>::cast(Object::GetProperty(
1211       isolate()->js_builtins_object(), constr).ToHandleChecked());
1212   Handle<Object> argv[] = { message };
1213
1214   // Invoke the JavaScript factory method. If an exception is thrown while
1215   // running the factory method, use the exception as the result.
1216   Handle<Object> result;
1217   MaybeHandle<Object> exception;
1218   if (!Execution::TryCall(fun,
1219                           isolate()->js_builtins_object(),
1220                           arraysize(argv),
1221                           argv,
1222                           &exception).ToHandle(&result)) {
1223     return exception;
1224   }
1225   return result;
1226 }
1227
1228
1229 void Factory::InitializeFunction(Handle<JSFunction> function,
1230                                  Handle<SharedFunctionInfo> info,
1231                                  Handle<Context> context) {
1232   function->initialize_properties();
1233   function->initialize_elements();
1234   function->set_shared(*info);
1235   function->set_code(info->code());
1236   function->set_context(*context);
1237   function->set_prototype_or_initial_map(*the_hole_value());
1238   function->set_literals_or_bindings(*empty_fixed_array());
1239   function->set_next_function_link(*undefined_value());
1240 }
1241
1242
1243 Handle<JSFunction> Factory::NewFunction(Handle<Map> map,
1244                                         Handle<SharedFunctionInfo> info,
1245                                         Handle<Context> context,
1246                                         PretenureFlag pretenure) {
1247   AllocationSpace space = pretenure == TENURED ? OLD_POINTER_SPACE : NEW_SPACE;
1248   Handle<JSFunction> result = New<JSFunction>(map, space);
1249   InitializeFunction(result, info, context);
1250   return result;
1251 }
1252
1253
1254 Handle<JSFunction> Factory::NewFunction(Handle<Map> map,
1255                                         Handle<String> name,
1256                                         MaybeHandle<Code> code) {
1257   Handle<Context> context(isolate()->native_context());
1258   Handle<SharedFunctionInfo> info = NewSharedFunctionInfo(name, code);
1259   DCHECK((info->strict_mode() == SLOPPY) &&
1260          (map.is_identical_to(isolate()->sloppy_function_map()) ||
1261           map.is_identical_to(
1262               isolate()->sloppy_function_without_prototype_map()) ||
1263           map.is_identical_to(
1264               isolate()->sloppy_function_with_readonly_prototype_map())));
1265   return NewFunction(map, info, context);
1266 }
1267
1268
1269 Handle<JSFunction> Factory::NewFunction(Handle<String> name) {
1270   return NewFunction(
1271       isolate()->sloppy_function_map(), name, MaybeHandle<Code>());
1272 }
1273
1274
1275 Handle<JSFunction> Factory::NewFunctionWithoutPrototype(Handle<String> name,
1276                                                         Handle<Code> code) {
1277   return NewFunction(
1278       isolate()->sloppy_function_without_prototype_map(), name, code);
1279 }
1280
1281
1282 Handle<JSFunction> Factory::NewFunction(Handle<String> name,
1283                                         Handle<Code> code,
1284                                         Handle<Object> prototype,
1285                                         bool read_only_prototype) {
1286   Handle<Map> map = read_only_prototype
1287       ? isolate()->sloppy_function_with_readonly_prototype_map()
1288       : isolate()->sloppy_function_map();
1289   Handle<JSFunction> result = NewFunction(map, name, code);
1290   result->set_prototype_or_initial_map(*prototype);
1291   return result;
1292 }
1293
1294
1295 Handle<JSFunction> Factory::NewFunction(Handle<String> name,
1296                                         Handle<Code> code,
1297                                         Handle<Object> prototype,
1298                                         InstanceType type,
1299                                         int instance_size,
1300                                         bool read_only_prototype) {
1301   // Allocate the function
1302   Handle<JSFunction> function = NewFunction(
1303       name, code, prototype, read_only_prototype);
1304
1305   Handle<Map> initial_map = NewMap(
1306       type, instance_size, GetInitialFastElementsKind());
1307   if (prototype->IsTheHole() && !function->shared()->is_generator()) {
1308     prototype = NewFunctionPrototype(function);
1309   }
1310
1311   JSFunction::SetInitialMap(function, initial_map,
1312                             Handle<JSReceiver>::cast(prototype));
1313
1314   return function;
1315 }
1316
1317
1318 Handle<JSFunction> Factory::NewFunction(Handle<String> name,
1319                                         Handle<Code> code,
1320                                         InstanceType type,
1321                                         int instance_size) {
1322   return NewFunction(name, code, the_hole_value(), type, instance_size);
1323 }
1324
1325
1326 Handle<JSObject> Factory::NewFunctionPrototype(Handle<JSFunction> function) {
1327   // Make sure to use globals from the function's context, since the function
1328   // can be from a different context.
1329   Handle<Context> native_context(function->context()->native_context());
1330   Handle<Map> new_map;
1331   if (function->shared()->is_generator()) {
1332     // Generator prototypes can share maps since they don't have "constructor"
1333     // properties.
1334     new_map = handle(native_context->generator_object_prototype_map());
1335   } else {
1336     // Each function prototype gets a fresh map to avoid unwanted sharing of
1337     // maps between prototypes of different constructors.
1338     Handle<JSFunction> object_function(native_context->object_function());
1339     DCHECK(object_function->has_initial_map());
1340     new_map = handle(object_function->initial_map());
1341   }
1342
1343   DCHECK(!new_map->is_prototype_map());
1344   Handle<JSObject> prototype = NewJSObjectFromMap(new_map);
1345
1346   if (!function->shared()->is_generator()) {
1347     JSObject::AddProperty(prototype, constructor_string(), function, DONT_ENUM);
1348   }
1349
1350   return prototype;
1351 }
1352
1353
1354 Handle<JSFunction> Factory::NewFunctionFromSharedFunctionInfo(
1355     Handle<SharedFunctionInfo> info,
1356     Handle<Context> context,
1357     PretenureFlag pretenure) {
1358   int map_index = Context::FunctionMapIndex(info->strict_mode(), info->kind());
1359   Handle<Map> map(Map::cast(context->native_context()->get(map_index)));
1360   Handle<JSFunction> result = NewFunction(map, info, context, pretenure);
1361
1362   if (info->ic_age() != isolate()->heap()->global_ic_age()) {
1363     info->ResetForNewContext(isolate()->heap()->global_ic_age());
1364   }
1365
1366   int index = info->SearchOptimizedCodeMap(context->native_context(),
1367                                            BailoutId::None());
1368   if (!info->bound() && index < 0) {
1369     int number_of_literals = info->num_literals();
1370     Handle<FixedArray> literals = NewFixedArray(number_of_literals, pretenure);
1371     if (number_of_literals > 0) {
1372       // Store the native context in the literals array prefix. This
1373       // context will be used when creating object, regexp and array
1374       // literals in this function.
1375       literals->set(JSFunction::kLiteralNativeContextIndex,
1376                     context->native_context());
1377     }
1378     result->set_literals(*literals);
1379   }
1380
1381   if (index > 0) {
1382     // Caching of optimized code enabled and optimized code found.
1383     FixedArray* literals = info->GetLiteralsFromOptimizedCodeMap(index);
1384     if (literals != NULL) result->set_literals(literals);
1385     Code* code = info->GetCodeFromOptimizedCodeMap(index);
1386     DCHECK(!code->marked_for_deoptimization());
1387     result->ReplaceCode(code);
1388     return result;
1389   }
1390
1391   if (isolate()->use_crankshaft() &&
1392       FLAG_always_opt &&
1393       result->is_compiled() &&
1394       !info->is_toplevel() &&
1395       info->allows_lazy_compilation() &&
1396       !info->optimization_disabled() &&
1397       !isolate()->DebuggerHasBreakPoints()) {
1398     result->MarkForOptimization();
1399   }
1400   return result;
1401 }
1402
1403
1404 Handle<ScopeInfo> Factory::NewScopeInfo(int length) {
1405   Handle<FixedArray> array = NewFixedArray(length, TENURED);
1406   array->set_map_no_write_barrier(*scope_info_map());
1407   Handle<ScopeInfo> scope_info = Handle<ScopeInfo>::cast(array);
1408   return scope_info;
1409 }
1410
1411
1412 Handle<JSObject> Factory::NewExternal(void* value) {
1413   Handle<Foreign> foreign = NewForeign(static_cast<Address>(value));
1414   Handle<JSObject> external = NewJSObjectFromMap(external_map());
1415   external->SetInternalField(0, *foreign);
1416   return external;
1417 }
1418
1419
1420 Handle<Code> Factory::NewCodeRaw(int object_size, bool immovable) {
1421   CALL_HEAP_FUNCTION(isolate(),
1422                      isolate()->heap()->AllocateCode(object_size, immovable),
1423                      Code);
1424 }
1425
1426
1427 Handle<Code> Factory::NewCode(const CodeDesc& desc,
1428                               Code::Flags flags,
1429                               Handle<Object> self_ref,
1430                               bool immovable,
1431                               bool crankshafted,
1432                               int prologue_offset,
1433                               bool is_debug) {
1434   Handle<ByteArray> reloc_info = NewByteArray(desc.reloc_size, TENURED);
1435   Handle<ConstantPoolArray> constant_pool =
1436       desc.origin->NewConstantPool(isolate());
1437
1438   // Compute size.
1439   int body_size = RoundUp(desc.instr_size, kObjectAlignment);
1440   int obj_size = Code::SizeFor(body_size);
1441
1442   Handle<Code> code = NewCodeRaw(obj_size, immovable);
1443   DCHECK(isolate()->code_range() == NULL ||
1444          !isolate()->code_range()->valid() ||
1445          isolate()->code_range()->contains(code->address()));
1446
1447   // The code object has not been fully initialized yet.  We rely on the
1448   // fact that no allocation will happen from this point on.
1449   DisallowHeapAllocation no_gc;
1450   code->set_gc_metadata(Smi::FromInt(0));
1451   code->set_ic_age(isolate()->heap()->global_ic_age());
1452   code->set_instruction_size(desc.instr_size);
1453   code->set_relocation_info(*reloc_info);
1454   code->set_flags(flags);
1455   code->set_raw_kind_specific_flags1(0);
1456   code->set_raw_kind_specific_flags2(0);
1457   code->set_is_crankshafted(crankshafted);
1458   code->set_deoptimization_data(*empty_fixed_array(), SKIP_WRITE_BARRIER);
1459   code->set_raw_type_feedback_info(Smi::FromInt(0));
1460   code->set_next_code_link(*undefined_value());
1461   code->set_handler_table(*empty_fixed_array(), SKIP_WRITE_BARRIER);
1462   code->set_prologue_offset(prologue_offset);
1463   if (code->kind() == Code::OPTIMIZED_FUNCTION) {
1464     code->set_marked_for_deoptimization(false);
1465   }
1466
1467   if (is_debug) {
1468     DCHECK(code->kind() == Code::FUNCTION);
1469     code->set_has_debug_break_slots(true);
1470   }
1471
1472   desc.origin->PopulateConstantPool(*constant_pool);
1473   code->set_constant_pool(*constant_pool);
1474
1475   // Allow self references to created code object by patching the handle to
1476   // point to the newly allocated Code object.
1477   if (!self_ref.is_null()) *(self_ref.location()) = *code;
1478
1479   // Migrate generated code.
1480   // The generated code can contain Object** values (typically from handles)
1481   // that are dereferenced during the copy to point directly to the actual heap
1482   // objects. These pointers can include references to the code object itself,
1483   // through the self_reference parameter.
1484   code->CopyFrom(desc);
1485
1486 #ifdef VERIFY_HEAP
1487   if (FLAG_verify_heap) code->ObjectVerify();
1488 #endif
1489   return code;
1490 }
1491
1492
1493 Handle<Code> Factory::CopyCode(Handle<Code> code) {
1494   CALL_HEAP_FUNCTION(isolate(),
1495                      isolate()->heap()->CopyCode(*code),
1496                      Code);
1497 }
1498
1499
1500 Handle<Code> Factory::CopyCode(Handle<Code> code, Vector<byte> reloc_info) {
1501   CALL_HEAP_FUNCTION(isolate(),
1502                      isolate()->heap()->CopyCode(*code, reloc_info),
1503                      Code);
1504 }
1505
1506
1507 Handle<JSObject> Factory::NewJSObject(Handle<JSFunction> constructor,
1508                                       PretenureFlag pretenure) {
1509   JSFunction::EnsureHasInitialMap(constructor);
1510   CALL_HEAP_FUNCTION(
1511       isolate(),
1512       isolate()->heap()->AllocateJSObject(*constructor, pretenure), JSObject);
1513 }
1514
1515
1516 Handle<JSObject> Factory::NewJSObjectWithMemento(
1517     Handle<JSFunction> constructor,
1518     Handle<AllocationSite> site) {
1519   JSFunction::EnsureHasInitialMap(constructor);
1520   CALL_HEAP_FUNCTION(
1521       isolate(),
1522       isolate()->heap()->AllocateJSObject(*constructor, NOT_TENURED, *site),
1523       JSObject);
1524 }
1525
1526
1527 Handle<JSModule> Factory::NewJSModule(Handle<Context> context,
1528                                       Handle<ScopeInfo> scope_info) {
1529   // Allocate a fresh map. Modules do not have a prototype.
1530   Handle<Map> map = NewMap(JS_MODULE_TYPE, JSModule::kSize);
1531   // Allocate the object based on the map.
1532   Handle<JSModule> module =
1533       Handle<JSModule>::cast(NewJSObjectFromMap(map, TENURED));
1534   module->set_context(*context);
1535   module->set_scope_info(*scope_info);
1536   return module;
1537 }
1538
1539
1540 Handle<GlobalObject> Factory::NewGlobalObject(Handle<JSFunction> constructor) {
1541   DCHECK(constructor->has_initial_map());
1542   Handle<Map> map(constructor->initial_map());
1543   DCHECK(map->is_dictionary_map());
1544
1545   // Make sure no field properties are described in the initial map.
1546   // This guarantees us that normalizing the properties does not
1547   // require us to change property values to PropertyCells.
1548   DCHECK(map->NextFreePropertyIndex() == 0);
1549
1550   // Make sure we don't have a ton of pre-allocated slots in the
1551   // global objects. They will be unused once we normalize the object.
1552   DCHECK(map->unused_property_fields() == 0);
1553   DCHECK(map->inobject_properties() == 0);
1554
1555   // Initial size of the backing store to avoid resize of the storage during
1556   // bootstrapping. The size differs between the JS global object ad the
1557   // builtins object.
1558   int initial_size = map->instance_type() == JS_GLOBAL_OBJECT_TYPE ? 64 : 512;
1559
1560   // Allocate a dictionary object for backing storage.
1561   int at_least_space_for = map->NumberOfOwnDescriptors() * 2 + initial_size;
1562   Handle<NameDictionary> dictionary =
1563       NameDictionary::New(isolate(), at_least_space_for);
1564
1565   // The global object might be created from an object template with accessors.
1566   // Fill these accessors into the dictionary.
1567   Handle<DescriptorArray> descs(map->instance_descriptors());
1568   for (int i = 0; i < map->NumberOfOwnDescriptors(); i++) {
1569     PropertyDetails details = descs->GetDetails(i);
1570     DCHECK(details.type() == CALLBACKS);  // Only accessors are expected.
1571     PropertyDetails d = PropertyDetails(details.attributes(), CALLBACKS, i + 1);
1572     Handle<Name> name(descs->GetKey(i));
1573     Handle<Object> value(descs->GetCallbacksObject(i), isolate());
1574     Handle<PropertyCell> cell = NewPropertyCell(value);
1575     // |dictionary| already contains enough space for all properties.
1576     USE(NameDictionary::Add(dictionary, name, cell, d));
1577   }
1578
1579   // Allocate the global object and initialize it with the backing store.
1580   Handle<GlobalObject> global = New<GlobalObject>(map, OLD_POINTER_SPACE);
1581   isolate()->heap()->InitializeJSObjectFromMap(*global, *dictionary, *map);
1582
1583   // Create a new map for the global object.
1584   Handle<Map> new_map = Map::CopyDropDescriptors(map);
1585   new_map->set_dictionary_map(true);
1586
1587   // Set up the global object as a normalized object.
1588   global->set_map(*new_map);
1589   global->set_properties(*dictionary);
1590
1591   // Make sure result is a global object with properties in dictionary.
1592   DCHECK(global->IsGlobalObject() && !global->HasFastProperties());
1593   return global;
1594 }
1595
1596
1597 Handle<JSObject> Factory::NewJSObjectFromMap(
1598     Handle<Map> map,
1599     PretenureFlag pretenure,
1600     bool alloc_props,
1601     Handle<AllocationSite> allocation_site) {
1602   CALL_HEAP_FUNCTION(
1603       isolate(),
1604       isolate()->heap()->AllocateJSObjectFromMap(
1605           *map,
1606           pretenure,
1607           alloc_props,
1608           allocation_site.is_null() ? NULL : *allocation_site),
1609       JSObject);
1610 }
1611
1612
1613 Handle<JSArray> Factory::NewJSArray(ElementsKind elements_kind,
1614                                     PretenureFlag pretenure) {
1615   Context* native_context = isolate()->context()->native_context();
1616   JSFunction* array_function = native_context->array_function();
1617   Map* map = array_function->initial_map();
1618   Map* transition_map = isolate()->get_initial_js_array_map(elements_kind);
1619   if (transition_map != NULL) map = transition_map;
1620   return Handle<JSArray>::cast(NewJSObjectFromMap(handle(map), pretenure));
1621 }
1622
1623
1624 Handle<JSArray> Factory::NewJSArray(ElementsKind elements_kind,
1625                                     int length,
1626                                     int capacity,
1627                                     ArrayStorageAllocationMode mode,
1628                                     PretenureFlag pretenure) {
1629   Handle<JSArray> array = NewJSArray(elements_kind, pretenure);
1630   NewJSArrayStorage(array, length, capacity, mode);
1631   return array;
1632 }
1633
1634
1635 Handle<JSArray> Factory::NewJSArrayWithElements(Handle<FixedArrayBase> elements,
1636                                                 ElementsKind elements_kind,
1637                                                 int length,
1638                                                 PretenureFlag pretenure) {
1639   DCHECK(length <= elements->length());
1640   Handle<JSArray> array = NewJSArray(elements_kind, pretenure);
1641
1642   array->set_elements(*elements);
1643   array->set_length(Smi::FromInt(length));
1644   JSObject::ValidateElements(array);
1645   return array;
1646 }
1647
1648
1649 void Factory::NewJSArrayStorage(Handle<JSArray> array,
1650                                 int length,
1651                                 int capacity,
1652                                 ArrayStorageAllocationMode mode) {
1653   DCHECK(capacity >= length);
1654
1655   if (capacity == 0) {
1656     array->set_length(Smi::FromInt(0));
1657     array->set_elements(*empty_fixed_array());
1658     return;
1659   }
1660
1661   Handle<FixedArrayBase> elms;
1662   ElementsKind elements_kind = array->GetElementsKind();
1663   if (IsFastDoubleElementsKind(elements_kind)) {
1664     if (mode == DONT_INITIALIZE_ARRAY_ELEMENTS) {
1665       elms = NewFixedDoubleArray(capacity);
1666     } else {
1667       DCHECK(mode == INITIALIZE_ARRAY_ELEMENTS_WITH_HOLE);
1668       elms = NewFixedDoubleArrayWithHoles(capacity);
1669     }
1670   } else {
1671     DCHECK(IsFastSmiOrObjectElementsKind(elements_kind));
1672     if (mode == DONT_INITIALIZE_ARRAY_ELEMENTS) {
1673       elms = NewUninitializedFixedArray(capacity);
1674     } else {
1675       DCHECK(mode == INITIALIZE_ARRAY_ELEMENTS_WITH_HOLE);
1676       elms = NewFixedArrayWithHoles(capacity);
1677     }
1678   }
1679
1680   array->set_elements(*elms);
1681   array->set_length(Smi::FromInt(length));
1682 }
1683
1684
1685 Handle<JSGeneratorObject> Factory::NewJSGeneratorObject(
1686     Handle<JSFunction> function) {
1687   DCHECK(function->shared()->is_generator());
1688   JSFunction::EnsureHasInitialMap(function);
1689   Handle<Map> map(function->initial_map());
1690   DCHECK(map->instance_type() == JS_GENERATOR_OBJECT_TYPE);
1691   CALL_HEAP_FUNCTION(
1692       isolate(),
1693       isolate()->heap()->AllocateJSObjectFromMap(*map),
1694       JSGeneratorObject);
1695 }
1696
1697
1698 Handle<JSArrayBuffer> Factory::NewJSArrayBuffer() {
1699   Handle<JSFunction> array_buffer_fun(
1700       isolate()->native_context()->array_buffer_fun());
1701   CALL_HEAP_FUNCTION(
1702       isolate(),
1703       isolate()->heap()->AllocateJSObject(*array_buffer_fun),
1704       JSArrayBuffer);
1705 }
1706
1707
1708 Handle<JSDataView> Factory::NewJSDataView() {
1709   Handle<JSFunction> data_view_fun(
1710       isolate()->native_context()->data_view_fun());
1711   CALL_HEAP_FUNCTION(
1712       isolate(),
1713       isolate()->heap()->AllocateJSObject(*data_view_fun),
1714       JSDataView);
1715 }
1716
1717
1718 static JSFunction* GetTypedArrayFun(ExternalArrayType type,
1719                                     Isolate* isolate) {
1720   Context* native_context = isolate->context()->native_context();
1721   switch (type) {
1722 #define TYPED_ARRAY_FUN(Type, type, TYPE, ctype, size)                        \
1723     case kExternal##Type##Array:                                              \
1724       return native_context->type##_array_fun();
1725
1726     TYPED_ARRAYS(TYPED_ARRAY_FUN)
1727 #undef TYPED_ARRAY_FUN
1728
1729     default:
1730       UNREACHABLE();
1731       return NULL;
1732   }
1733 }
1734
1735
1736 Handle<JSTypedArray> Factory::NewJSTypedArray(ExternalArrayType type) {
1737   Handle<JSFunction> typed_array_fun_handle(GetTypedArrayFun(type, isolate()));
1738
1739   CALL_HEAP_FUNCTION(
1740       isolate(),
1741       isolate()->heap()->AllocateJSObject(*typed_array_fun_handle),
1742       JSTypedArray);
1743 }
1744
1745
1746 Handle<JSProxy> Factory::NewJSProxy(Handle<Object> handler,
1747                                     Handle<Object> prototype) {
1748   // Allocate map.
1749   // TODO(rossberg): Once we optimize proxies, think about a scheme to share
1750   // maps. Will probably depend on the identity of the handler object, too.
1751   Handle<Map> map = NewMap(JS_PROXY_TYPE, JSProxy::kSize);
1752   map->set_prototype(*prototype);
1753
1754   // Allocate the proxy object.
1755   Handle<JSProxy> result = New<JSProxy>(map, NEW_SPACE);
1756   result->InitializeBody(map->instance_size(), Smi::FromInt(0));
1757   result->set_handler(*handler);
1758   result->set_hash(*undefined_value(), SKIP_WRITE_BARRIER);
1759   return result;
1760 }
1761
1762
1763 Handle<JSProxy> Factory::NewJSFunctionProxy(Handle<Object> handler,
1764                                             Handle<Object> call_trap,
1765                                             Handle<Object> construct_trap,
1766                                             Handle<Object> prototype) {
1767   // Allocate map.
1768   // TODO(rossberg): Once we optimize proxies, think about a scheme to share
1769   // maps. Will probably depend on the identity of the handler object, too.
1770   Handle<Map> map = NewMap(JS_FUNCTION_PROXY_TYPE, JSFunctionProxy::kSize);
1771   map->set_prototype(*prototype);
1772
1773   // Allocate the proxy object.
1774   Handle<JSFunctionProxy> result = New<JSFunctionProxy>(map, NEW_SPACE);
1775   result->InitializeBody(map->instance_size(), Smi::FromInt(0));
1776   result->set_handler(*handler);
1777   result->set_hash(*undefined_value(), SKIP_WRITE_BARRIER);
1778   result->set_call_trap(*call_trap);
1779   result->set_construct_trap(*construct_trap);
1780   return result;
1781 }
1782
1783
1784 void Factory::ReinitializeJSProxy(Handle<JSProxy> proxy, InstanceType type,
1785                                   int size) {
1786   DCHECK(type == JS_OBJECT_TYPE || type == JS_FUNCTION_TYPE);
1787
1788   // Allocate fresh map.
1789   // TODO(rossberg): Once we optimize proxies, cache these maps.
1790   Handle<Map> map = NewMap(type, size);
1791
1792   // Check that the receiver has at least the size of the fresh object.
1793   int size_difference = proxy->map()->instance_size() - map->instance_size();
1794   DCHECK(size_difference >= 0);
1795
1796   map->set_prototype(proxy->map()->prototype());
1797
1798   // Allocate the backing storage for the properties.
1799   int prop_size = map->InitialPropertiesLength();
1800   Handle<FixedArray> properties = NewFixedArray(prop_size, TENURED);
1801
1802   Heap* heap = isolate()->heap();
1803   MaybeHandle<SharedFunctionInfo> shared;
1804   if (type == JS_FUNCTION_TYPE) {
1805     OneByteStringKey key(STATIC_CHAR_VECTOR("<freezing call trap>"),
1806                          heap->HashSeed());
1807     Handle<String> name = InternalizeStringWithKey(&key);
1808     shared = NewSharedFunctionInfo(name, MaybeHandle<Code>());
1809   }
1810
1811   // In order to keep heap in consistent state there must be no allocations
1812   // before object re-initialization is finished and filler object is installed.
1813   DisallowHeapAllocation no_allocation;
1814
1815   // Put in filler if the new object is smaller than the old.
1816   if (size_difference > 0) {
1817     Address address = proxy->address();
1818     heap->CreateFillerObjectAt(address + map->instance_size(), size_difference);
1819     heap->AdjustLiveBytes(address, -size_difference, Heap::FROM_MUTATOR);
1820   }
1821
1822   // Reset the map for the object.
1823   proxy->synchronized_set_map(*map);
1824   Handle<JSObject> jsobj = Handle<JSObject>::cast(proxy);
1825
1826   // Reinitialize the object from the constructor map.
1827   heap->InitializeJSObjectFromMap(*jsobj, *properties, *map);
1828
1829   // The current native context is used to set up certain bits.
1830   // TODO(adamk): Using the current context seems wrong, it should be whatever
1831   // context the JSProxy originated in. But that context isn't stored anywhere.
1832   Handle<Context> context(isolate()->native_context());
1833
1834   // Functions require some minimal initialization.
1835   if (type == JS_FUNCTION_TYPE) {
1836     map->set_function_with_prototype(true);
1837     Handle<JSFunction> js_function = Handle<JSFunction>::cast(proxy);
1838     InitializeFunction(js_function, shared.ToHandleChecked(), context);
1839   } else {
1840     // Provide JSObjects with a constructor.
1841     map->set_constructor(context->object_function());
1842   }
1843 }
1844
1845
1846 void Factory::ReinitializeJSGlobalProxy(Handle<JSGlobalProxy> object,
1847                                         Handle<JSFunction> constructor) {
1848   DCHECK(constructor->has_initial_map());
1849   Handle<Map> map(constructor->initial_map(), isolate());
1850
1851   // The proxy's hash should be retained across reinitialization.
1852   Handle<Object> hash(object->hash(), isolate());
1853
1854   // Check that the already allocated object has the same size and type as
1855   // objects allocated using the constructor.
1856   DCHECK(map->instance_size() == object->map()->instance_size());
1857   DCHECK(map->instance_type() == object->map()->instance_type());
1858
1859   // Allocate the backing storage for the properties.
1860   int prop_size = map->InitialPropertiesLength();
1861   Handle<FixedArray> properties = NewFixedArray(prop_size, TENURED);
1862
1863   // In order to keep heap in consistent state there must be no allocations
1864   // before object re-initialization is finished.
1865   DisallowHeapAllocation no_allocation;
1866
1867   // Reset the map for the object.
1868   object->synchronized_set_map(*map);
1869
1870   Heap* heap = isolate()->heap();
1871   // Reinitialize the object from the constructor map.
1872   heap->InitializeJSObjectFromMap(*object, *properties, *map);
1873
1874   // Restore the saved hash.
1875   object->set_hash(*hash);
1876 }
1877
1878
1879 void Factory::BecomeJSObject(Handle<JSProxy> proxy) {
1880   ReinitializeJSProxy(proxy, JS_OBJECT_TYPE, JSObject::kHeaderSize);
1881 }
1882
1883
1884 void Factory::BecomeJSFunction(Handle<JSProxy> proxy) {
1885   ReinitializeJSProxy(proxy, JS_FUNCTION_TYPE, JSFunction::kSize);
1886 }
1887
1888
1889 Handle<TypeFeedbackVector> Factory::NewTypeFeedbackVector(int slot_count) {
1890   // Ensure we can skip the write barrier
1891   DCHECK_EQ(isolate()->heap()->uninitialized_symbol(),
1892             *TypeFeedbackVector::UninitializedSentinel(isolate()));
1893
1894   if (slot_count == 0) {
1895     return Handle<TypeFeedbackVector>::cast(empty_fixed_array());
1896   }
1897
1898   CALL_HEAP_FUNCTION(isolate(),
1899                      isolate()->heap()->AllocateFixedArrayWithFiller(
1900                          slot_count, TENURED,
1901                          *TypeFeedbackVector::UninitializedSentinel(isolate())),
1902                      TypeFeedbackVector);
1903 }
1904
1905
1906 Handle<SharedFunctionInfo> Factory::NewSharedFunctionInfo(
1907     Handle<String> name, int number_of_literals, FunctionKind kind,
1908     Handle<Code> code, Handle<ScopeInfo> scope_info,
1909     Handle<TypeFeedbackVector> feedback_vector) {
1910   DCHECK(IsValidFunctionKind(kind));
1911   Handle<SharedFunctionInfo> shared = NewSharedFunctionInfo(name, code);
1912   shared->set_scope_info(*scope_info);
1913   shared->set_feedback_vector(*feedback_vector);
1914   shared->set_kind(kind);
1915   int literals_array_size = number_of_literals;
1916   // If the function contains object, regexp or array literals,
1917   // allocate extra space for a literals array prefix containing the
1918   // context.
1919   if (number_of_literals > 0) {
1920     literals_array_size += JSFunction::kLiteralsPrefixSize;
1921   }
1922   shared->set_num_literals(literals_array_size);
1923   if (IsGeneratorFunction(kind)) {
1924     shared->set_instance_class_name(isolate()->heap()->Generator_string());
1925     shared->DisableOptimization(kGenerator);
1926   }
1927   return shared;
1928 }
1929
1930
1931 Handle<JSMessageObject> Factory::NewJSMessageObject(
1932     Handle<String> type,
1933     Handle<JSArray> arguments,
1934     int start_position,
1935     int end_position,
1936     Handle<Object> script,
1937     Handle<Object> stack_frames) {
1938   Handle<Map> map = message_object_map();
1939   Handle<JSMessageObject> message = New<JSMessageObject>(map, NEW_SPACE);
1940   message->set_properties(*empty_fixed_array(), SKIP_WRITE_BARRIER);
1941   message->initialize_elements();
1942   message->set_elements(*empty_fixed_array(), SKIP_WRITE_BARRIER);
1943   message->set_type(*type);
1944   message->set_arguments(*arguments);
1945   message->set_start_position(start_position);
1946   message->set_end_position(end_position);
1947   message->set_script(*script);
1948   message->set_stack_frames(*stack_frames);
1949   return message;
1950 }
1951
1952
1953 Handle<SharedFunctionInfo> Factory::NewSharedFunctionInfo(
1954     Handle<String> name,
1955     MaybeHandle<Code> maybe_code) {
1956   Handle<Map> map = shared_function_info_map();
1957   Handle<SharedFunctionInfo> share = New<SharedFunctionInfo>(map,
1958                                                              OLD_POINTER_SPACE);
1959
1960   // Set pointer fields.
1961   share->set_name(*name);
1962   Handle<Code> code;
1963   if (!maybe_code.ToHandle(&code)) {
1964     code = handle(isolate()->builtins()->builtin(Builtins::kIllegal));
1965   }
1966   share->set_code(*code);
1967   share->set_optimized_code_map(Smi::FromInt(0));
1968   share->set_scope_info(ScopeInfo::Empty(isolate()));
1969   Code* construct_stub =
1970       isolate()->builtins()->builtin(Builtins::kJSConstructStubGeneric);
1971   share->set_construct_stub(construct_stub);
1972   share->set_instance_class_name(*Object_string());
1973   share->set_function_data(*undefined_value(), SKIP_WRITE_BARRIER);
1974   share->set_script(*undefined_value(), SKIP_WRITE_BARRIER);
1975   share->set_debug_info(*undefined_value(), SKIP_WRITE_BARRIER);
1976   share->set_inferred_name(*empty_string(), SKIP_WRITE_BARRIER);
1977   Handle<TypeFeedbackVector> feedback_vector = NewTypeFeedbackVector(0);
1978   share->set_feedback_vector(*feedback_vector, SKIP_WRITE_BARRIER);
1979   share->set_profiler_ticks(0);
1980   share->set_ast_node_count(0);
1981   share->set_counters(0);
1982
1983   // Set integer fields (smi or int, depending on the architecture).
1984   share->set_length(0);
1985   share->set_formal_parameter_count(0);
1986   share->set_expected_nof_properties(0);
1987   share->set_num_literals(0);
1988   share->set_start_position_and_type(0);
1989   share->set_end_position(0);
1990   share->set_function_token_position(0);
1991   // All compiler hints default to false or 0.
1992   share->set_compiler_hints(0);
1993   share->set_opt_count_and_bailout_reason(0);
1994
1995   return share;
1996 }
1997
1998
1999 static inline int NumberCacheHash(Handle<FixedArray> cache,
2000                                   Handle<Object> number) {
2001   int mask = (cache->length() >> 1) - 1;
2002   if (number->IsSmi()) {
2003     return Handle<Smi>::cast(number)->value() & mask;
2004   } else {
2005     DoubleRepresentation rep(number->Number());
2006     return
2007         (static_cast<int>(rep.bits) ^ static_cast<int>(rep.bits >> 32)) & mask;
2008   }
2009 }
2010
2011
2012 Handle<Object> Factory::GetNumberStringCache(Handle<Object> number) {
2013   DisallowHeapAllocation no_gc;
2014   int hash = NumberCacheHash(number_string_cache(), number);
2015   Object* key = number_string_cache()->get(hash * 2);
2016   if (key == *number || (key->IsHeapNumber() && number->IsHeapNumber() &&
2017                          key->Number() == number->Number())) {
2018     return Handle<String>(
2019         String::cast(number_string_cache()->get(hash * 2 + 1)), isolate());
2020   }
2021   return undefined_value();
2022 }
2023
2024
2025 void Factory::SetNumberStringCache(Handle<Object> number,
2026                                    Handle<String> string) {
2027   int hash = NumberCacheHash(number_string_cache(), number);
2028   if (number_string_cache()->get(hash * 2) != *undefined_value()) {
2029     int full_size = isolate()->heap()->FullSizeNumberStringCacheLength();
2030     if (number_string_cache()->length() != full_size) {
2031       // The first time we have a hash collision, we move to the full sized
2032       // number string cache.  The idea is to have a small number string
2033       // cache in the snapshot to keep  boot-time memory usage down.
2034       // If we expand the number string cache already while creating
2035       // the snapshot then that didn't work out.
2036       DCHECK(!isolate()->serializer_enabled() || FLAG_extra_code != NULL);
2037       Handle<FixedArray> new_cache = NewFixedArray(full_size, TENURED);
2038       isolate()->heap()->set_number_string_cache(*new_cache);
2039       return;
2040     }
2041   }
2042   number_string_cache()->set(hash * 2, *number);
2043   number_string_cache()->set(hash * 2 + 1, *string);
2044 }
2045
2046
2047 Handle<String> Factory::NumberToString(Handle<Object> number,
2048                                        bool check_number_string_cache) {
2049   isolate()->counters()->number_to_string_runtime()->Increment();
2050   if (check_number_string_cache) {
2051     Handle<Object> cached = GetNumberStringCache(number);
2052     if (!cached->IsUndefined()) return Handle<String>::cast(cached);
2053   }
2054
2055   char arr[100];
2056   Vector<char> buffer(arr, arraysize(arr));
2057   const char* str;
2058   if (number->IsSmi()) {
2059     int num = Handle<Smi>::cast(number)->value();
2060     str = IntToCString(num, buffer);
2061   } else {
2062     double num = Handle<HeapNumber>::cast(number)->value();
2063     str = DoubleToCString(num, buffer);
2064   }
2065
2066   // We tenure the allocated string since it is referenced from the
2067   // number-string cache which lives in the old space.
2068   Handle<String> js_string = NewStringFromAsciiChecked(str, TENURED);
2069   SetNumberStringCache(number, js_string);
2070   return js_string;
2071 }
2072
2073
2074 Handle<DebugInfo> Factory::NewDebugInfo(Handle<SharedFunctionInfo> shared) {
2075   // Get the original code of the function.
2076   Handle<Code> code(shared->code());
2077
2078   // Create a copy of the code before allocating the debug info object to avoid
2079   // allocation while setting up the debug info object.
2080   Handle<Code> original_code(*Factory::CopyCode(code));
2081
2082   // Allocate initial fixed array for active break points before allocating the
2083   // debug info object to avoid allocation while setting up the debug info
2084   // object.
2085   Handle<FixedArray> break_points(
2086       NewFixedArray(DebugInfo::kEstimatedNofBreakPointsInFunction));
2087
2088   // Create and set up the debug info object. Debug info contains function, a
2089   // copy of the original code, the executing code and initial fixed array for
2090   // active break points.
2091   Handle<DebugInfo> debug_info =
2092       Handle<DebugInfo>::cast(NewStruct(DEBUG_INFO_TYPE));
2093   debug_info->set_shared(*shared);
2094   debug_info->set_original_code(*original_code);
2095   debug_info->set_code(*code);
2096   debug_info->set_break_points(*break_points);
2097
2098   // Link debug info to function.
2099   shared->set_debug_info(*debug_info);
2100
2101   return debug_info;
2102 }
2103
2104
2105 Handle<JSObject> Factory::NewArgumentsObject(Handle<JSFunction> callee,
2106                                              int length) {
2107   bool strict_mode_callee = callee->shared()->strict_mode() == STRICT;
2108   Handle<Map> map = strict_mode_callee ? isolate()->strict_arguments_map()
2109                                        : isolate()->sloppy_arguments_map();
2110
2111   AllocationSiteUsageContext context(isolate(), Handle<AllocationSite>(),
2112                                      false);
2113   DCHECK(!isolate()->has_pending_exception());
2114   Handle<JSObject> result = NewJSObjectFromMap(map);
2115   Handle<Smi> value(Smi::FromInt(length), isolate());
2116   Object::SetProperty(result, length_string(), value, STRICT).Assert();
2117   if (!strict_mode_callee) {
2118     Object::SetProperty(result, callee_string(), callee, STRICT).Assert();
2119   }
2120   return result;
2121 }
2122
2123
2124 Handle<JSFunction> Factory::CreateApiFunction(
2125     Handle<FunctionTemplateInfo> obj,
2126     Handle<Object> prototype,
2127     ApiInstanceType instance_type) {
2128   Handle<Code> code = isolate()->builtins()->HandleApiCall();
2129   Handle<Code> construct_stub = isolate()->builtins()->JSConstructStubApi();
2130
2131   Handle<JSFunction> result;
2132   if (obj->remove_prototype()) {
2133     result = NewFunctionWithoutPrototype(empty_string(), code);
2134   } else {
2135     int internal_field_count = 0;
2136     if (!obj->instance_template()->IsUndefined()) {
2137       Handle<ObjectTemplateInfo> instance_template =
2138           Handle<ObjectTemplateInfo>(
2139               ObjectTemplateInfo::cast(obj->instance_template()));
2140       internal_field_count =
2141           Smi::cast(instance_template->internal_field_count())->value();
2142     }
2143
2144     // TODO(svenpanne) Kill ApiInstanceType and refactor things by generalizing
2145     // JSObject::GetHeaderSize.
2146     int instance_size = kPointerSize * internal_field_count;
2147     InstanceType type;
2148     switch (instance_type) {
2149       case JavaScriptObjectType:
2150         type = JS_OBJECT_TYPE;
2151         instance_size += JSObject::kHeaderSize;
2152         break;
2153       case GlobalObjectType:
2154         type = JS_GLOBAL_OBJECT_TYPE;
2155         instance_size += JSGlobalObject::kSize;
2156         break;
2157       case GlobalProxyType:
2158         type = JS_GLOBAL_PROXY_TYPE;
2159         instance_size += JSGlobalProxy::kSize;
2160         break;
2161       default:
2162         UNREACHABLE();
2163         type = JS_OBJECT_TYPE;  // Keep the compiler happy.
2164         break;
2165     }
2166
2167     result = NewFunction(empty_string(), code, prototype, type,
2168                          instance_size, obj->read_only_prototype());
2169   }
2170
2171   result->shared()->set_length(obj->length());
2172   Handle<Object> class_name(obj->class_name(), isolate());
2173   if (class_name->IsString()) {
2174     result->shared()->set_instance_class_name(*class_name);
2175     result->shared()->set_name(*class_name);
2176   }
2177   result->shared()->set_function_data(*obj);
2178   result->shared()->set_construct_stub(*construct_stub);
2179   result->shared()->DontAdaptArguments();
2180
2181   if (obj->remove_prototype()) {
2182     DCHECK(result->shared()->IsApiFunction());
2183     DCHECK(!result->has_initial_map());
2184     DCHECK(!result->has_prototype());
2185     return result;
2186   }
2187
2188   if (prototype->IsTheHole()) {
2189 #ifdef DEBUG
2190     LookupIterator it(handle(JSObject::cast(result->prototype())),
2191                       constructor_string(),
2192                       LookupIterator::OWN_SKIP_INTERCEPTOR);
2193     MaybeHandle<Object> maybe_prop = Object::GetProperty(&it);
2194     DCHECK(it.IsFound());
2195     DCHECK(maybe_prop.ToHandleChecked().is_identical_to(result));
2196 #endif
2197   } else {
2198     JSObject::AddProperty(handle(JSObject::cast(result->prototype())),
2199                           constructor_string(), result, DONT_ENUM);
2200   }
2201
2202   // Down from here is only valid for API functions that can be used as a
2203   // constructor (don't set the "remove prototype" flag).
2204
2205   Handle<Map> map(result->initial_map());
2206
2207   // Mark as undetectable if needed.
2208   if (obj->undetectable()) {
2209     map->set_is_undetectable();
2210   }
2211
2212   // Mark as hidden for the __proto__ accessor if needed.
2213   if (obj->hidden_prototype()) {
2214     map->set_is_hidden_prototype();
2215   }
2216
2217   // Mark as needs_access_check if needed.
2218   if (obj->needs_access_check()) {
2219     map->set_is_access_check_needed(true);
2220   }
2221
2222   // Set interceptor information in the map.
2223   if (!obj->named_property_handler()->IsUndefined()) {
2224     map->set_has_named_interceptor();
2225   }
2226   if (!obj->indexed_property_handler()->IsUndefined()) {
2227     map->set_has_indexed_interceptor();
2228   }
2229
2230   // Set instance call-as-function information in the map.
2231   if (!obj->instance_call_handler()->IsUndefined()) {
2232     map->set_has_instance_call_handler();
2233   }
2234
2235   // Recursively copy parent instance templates' accessors,
2236   // 'data' may be modified.
2237   int max_number_of_additional_properties = 0;
2238   int max_number_of_static_properties = 0;
2239   FunctionTemplateInfo* info = *obj;
2240   while (true) {
2241     if (!info->instance_template()->IsUndefined()) {
2242       Object* props =
2243           ObjectTemplateInfo::cast(
2244               info->instance_template())->property_accessors();
2245       if (!props->IsUndefined()) {
2246         Handle<Object> props_handle(props, isolate());
2247         NeanderArray props_array(props_handle);
2248         max_number_of_additional_properties += props_array.length();
2249       }
2250     }
2251     if (!info->property_accessors()->IsUndefined()) {
2252       Object* props = info->property_accessors();
2253       if (!props->IsUndefined()) {
2254         Handle<Object> props_handle(props, isolate());
2255         NeanderArray props_array(props_handle);
2256         max_number_of_static_properties += props_array.length();
2257       }
2258     }
2259     Object* parent = info->parent_template();
2260     if (parent->IsUndefined()) break;
2261     info = FunctionTemplateInfo::cast(parent);
2262   }
2263
2264   Map::EnsureDescriptorSlack(map, max_number_of_additional_properties);
2265
2266   // Use a temporary FixedArray to acculumate static accessors
2267   int valid_descriptors = 0;
2268   Handle<FixedArray> array;
2269   if (max_number_of_static_properties > 0) {
2270     array = NewFixedArray(max_number_of_static_properties);
2271   }
2272
2273   while (true) {
2274     // Install instance descriptors
2275     if (!obj->instance_template()->IsUndefined()) {
2276       Handle<ObjectTemplateInfo> instance =
2277           Handle<ObjectTemplateInfo>(
2278               ObjectTemplateInfo::cast(obj->instance_template()), isolate());
2279       Handle<Object> props = Handle<Object>(instance->property_accessors(),
2280                                             isolate());
2281       if (!props->IsUndefined()) {
2282         Map::AppendCallbackDescriptors(map, props);
2283       }
2284     }
2285     // Accumulate static accessors
2286     if (!obj->property_accessors()->IsUndefined()) {
2287       Handle<Object> props = Handle<Object>(obj->property_accessors(),
2288                                             isolate());
2289       valid_descriptors =
2290           AccessorInfo::AppendUnique(props, array, valid_descriptors);
2291     }
2292     // Climb parent chain
2293     Handle<Object> parent = Handle<Object>(obj->parent_template(), isolate());
2294     if (parent->IsUndefined()) break;
2295     obj = Handle<FunctionTemplateInfo>::cast(parent);
2296   }
2297
2298   // Install accumulated static accessors
2299   for (int i = 0; i < valid_descriptors; i++) {
2300     Handle<AccessorInfo> accessor(AccessorInfo::cast(array->get(i)));
2301     JSObject::SetAccessor(result, accessor).Assert();
2302   }
2303
2304   DCHECK(result->shared()->IsApiFunction());
2305   return result;
2306 }
2307
2308
2309 Handle<MapCache> Factory::AddToMapCache(Handle<Context> context,
2310                                         Handle<FixedArray> keys,
2311                                         Handle<Map> map) {
2312   Handle<MapCache> map_cache = handle(MapCache::cast(context->map_cache()));
2313   Handle<MapCache> result = MapCache::Put(map_cache, keys, map);
2314   context->set_map_cache(*result);
2315   return result;
2316 }
2317
2318
2319 Handle<Map> Factory::ObjectLiteralMapFromCache(Handle<Context> context,
2320                                                Handle<FixedArray> keys) {
2321   if (context->map_cache()->IsUndefined()) {
2322     // Allocate the new map cache for the native context.
2323     Handle<MapCache> new_cache = MapCache::New(isolate(), 24);
2324     context->set_map_cache(*new_cache);
2325   }
2326   // Check to see whether there is a matching element in the cache.
2327   Handle<MapCache> cache =
2328       Handle<MapCache>(MapCache::cast(context->map_cache()));
2329   Handle<Object> result = Handle<Object>(cache->Lookup(*keys), isolate());
2330   if (result->IsMap()) return Handle<Map>::cast(result);
2331   int length = keys->length();
2332   // Create a new map and add it to the cache. Reuse the initial map of the
2333   // Object function if the literal has no predeclared properties.
2334   Handle<Map> map = length == 0
2335                         ? handle(context->object_function()->initial_map())
2336                         : Map::Create(isolate(), length);
2337   AddToMapCache(context, keys, map);
2338   return map;
2339 }
2340
2341
2342 void Factory::SetRegExpAtomData(Handle<JSRegExp> regexp,
2343                                 JSRegExp::Type type,
2344                                 Handle<String> source,
2345                                 JSRegExp::Flags flags,
2346                                 Handle<Object> data) {
2347   Handle<FixedArray> store = NewFixedArray(JSRegExp::kAtomDataSize);
2348
2349   store->set(JSRegExp::kTagIndex, Smi::FromInt(type));
2350   store->set(JSRegExp::kSourceIndex, *source);
2351   store->set(JSRegExp::kFlagsIndex, Smi::FromInt(flags.value()));
2352   store->set(JSRegExp::kAtomPatternIndex, *data);
2353   regexp->set_data(*store);
2354 }
2355
2356 void Factory::SetRegExpIrregexpData(Handle<JSRegExp> regexp,
2357                                     JSRegExp::Type type,
2358                                     Handle<String> source,
2359                                     JSRegExp::Flags flags,
2360                                     int capture_count) {
2361   Handle<FixedArray> store = NewFixedArray(JSRegExp::kIrregexpDataSize);
2362   Smi* uninitialized = Smi::FromInt(JSRegExp::kUninitializedValue);
2363   store->set(JSRegExp::kTagIndex, Smi::FromInt(type));
2364   store->set(JSRegExp::kSourceIndex, *source);
2365   store->set(JSRegExp::kFlagsIndex, Smi::FromInt(flags.value()));
2366   store->set(JSRegExp::kIrregexpLatin1CodeIndex, uninitialized);
2367   store->set(JSRegExp::kIrregexpUC16CodeIndex, uninitialized);
2368   store->set(JSRegExp::kIrregexpLatin1CodeSavedIndex, uninitialized);
2369   store->set(JSRegExp::kIrregexpUC16CodeSavedIndex, uninitialized);
2370   store->set(JSRegExp::kIrregexpMaxRegisterCountIndex, Smi::FromInt(0));
2371   store->set(JSRegExp::kIrregexpCaptureCountIndex,
2372              Smi::FromInt(capture_count));
2373   regexp->set_data(*store);
2374 }
2375
2376
2377
2378 MaybeHandle<FunctionTemplateInfo> Factory::ConfigureInstance(
2379     Handle<FunctionTemplateInfo> desc, Handle<JSObject> instance) {
2380   // Configure the instance by adding the properties specified by the
2381   // instance template.
2382   Handle<Object> instance_template(desc->instance_template(), isolate());
2383   if (!instance_template->IsUndefined()) {
2384       RETURN_ON_EXCEPTION(
2385           isolate(),
2386           Execution::ConfigureInstance(isolate(), instance, instance_template),
2387           FunctionTemplateInfo);
2388   }
2389   return desc;
2390 }
2391
2392
2393 Handle<Object> Factory::GlobalConstantFor(Handle<String> name) {
2394   if (String::Equals(name, undefined_string())) return undefined_value();
2395   if (String::Equals(name, nan_string())) return nan_value();
2396   if (String::Equals(name, infinity_string())) return infinity_value();
2397   return Handle<Object>::null();
2398 }
2399
2400
2401 Handle<Object> Factory::ToBoolean(bool value) {
2402   return value ? true_value() : false_value();
2403 }
2404
2405
2406 } }  // namespace v8::internal