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      1 // Copyright 2016 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 #ifndef V8_CODE_STUB_ASSEMBLER_H_
      6 #define V8_CODE_STUB_ASSEMBLER_H_
      7 
      8 #include <functional>
      9 
     10 #include "src/base/macros.h"
     11 #include "src/compiler/code-assembler.h"
     12 #include "src/globals.h"
     13 #include "src/objects.h"
     14 #include "src/objects/bigint.h"
     15 #include "src/roots.h"
     16 
     17 namespace v8 {
     18 namespace internal {
     19 
     20 class CallInterfaceDescriptor;
     21 class CodeStubArguments;
     22 class CodeStubAssembler;
     23 class StatsCounter;
     24 class StubCache;
     25 
     26 enum class PrimitiveType { kBoolean, kNumber, kString, kSymbol };
     27 
     28 #define HEAP_MUTABLE_IMMOVABLE_OBJECT_LIST(V)                              \
     29   V(ArraySpeciesProtector, array_species_protector, ArraySpeciesProtector) \
     30   V(EmptyPropertyDictionary, empty_property_dictionary,                    \
     31     EmptyPropertyDictionary)                                               \
     32   V(PromiseSpeciesProtector, promise_species_protector,                    \
     33     PromiseSpeciesProtector)                                               \
     34   V(TypedArraySpeciesProtector, typed_array_species_protector,             \
     35     TypedArraySpeciesProtector)                                            \
     36   V(StoreHandler0Map, store_handler0_map, StoreHandler0Map)
     37 
     38 #define HEAP_IMMUTABLE_IMMOVABLE_OBJECT_LIST(V)                              \
     39   V(AccessorInfoMap, accessor_info_map, AccessorInfoMap)                     \
     40   V(AccessorPairMap, accessor_pair_map, AccessorPairMap)                     \
     41   V(AllocationSiteWithWeakNextMap, allocation_site_map, AllocationSiteMap)   \
     42   V(AllocationSiteWithoutWeakNextMap, allocation_site_without_weaknext_map,  \
     43     AllocationSiteWithoutWeakNextMap)                                        \
     44   V(BooleanMap, boolean_map, BooleanMap)                                     \
     45   V(CodeMap, code_map, CodeMap)                                              \
     46   V(EmptyFixedArray, empty_fixed_array, EmptyFixedArray)                     \
     47   V(EmptySlowElementDictionary, empty_slow_element_dictionary,               \
     48     EmptySlowElementDictionary)                                              \
     49   V(empty_string, empty_string, EmptyString)                                 \
     50   V(FalseValue, false_value, False)                                          \
     51   V(FeedbackVectorMap, feedback_vector_map, FeedbackVectorMap)               \
     52   V(FixedArrayMap, fixed_array_map, FixedArrayMap)                           \
     53   V(FixedCOWArrayMap, fixed_cow_array_map, FixedCOWArrayMap)                 \
     54   V(FixedDoubleArrayMap, fixed_double_array_map, FixedDoubleArrayMap)        \
     55   V(FunctionTemplateInfoMap, function_template_info_map,                     \
     56     FunctionTemplateInfoMap)                                                 \
     57   V(GlobalPropertyCellMap, global_property_cell_map, PropertyCellMap)        \
     58   V(has_instance_symbol, has_instance_symbol, HasInstanceSymbol)             \
     59   V(HeapNumberMap, heap_number_map, HeapNumberMap)                           \
     60   V(iterator_symbol, iterator_symbol, IteratorSymbol)                        \
     61   V(length_string, length_string, LengthString)                              \
     62   V(ManyClosuresCellMap, many_closures_cell_map, ManyClosuresCellMap)        \
     63   V(MetaMap, meta_map, MetaMap)                                              \
     64   V(MinusZeroValue, minus_zero_value, MinusZero)                             \
     65   V(MutableHeapNumberMap, mutable_heap_number_map, MutableHeapNumberMap)     \
     66   V(NanValue, nan_value, Nan)                                                \
     67   V(NoClosuresCellMap, no_closures_cell_map, NoClosuresCellMap)              \
     68   V(NullValue, null_value, Null)                                             \
     69   V(OneClosureCellMap, one_closure_cell_map, OneClosureCellMap)              \
     70   V(PreParsedScopeDataMap, pre_parsed_scope_data_map, PreParsedScopeDataMap) \
     71   V(prototype_string, prototype_string, PrototypeString)                     \
     72   V(SharedFunctionInfoMap, shared_function_info_map, SharedFunctionInfoMap)  \
     73   V(SymbolMap, symbol_map, SymbolMap)                                        \
     74   V(TheHoleValue, the_hole_value, TheHole)                                   \
     75   V(TransitionArrayMap, transition_array_map, TransitionArrayMap)            \
     76   V(TrueValue, true_value, True)                                             \
     77   V(Tuple2Map, tuple2_map, Tuple2Map)                                        \
     78   V(Tuple3Map, tuple3_map, Tuple3Map)                                        \
     79   V(ArrayBoilerplateDescriptionMap, array_boilerplate_description_map,       \
     80     ArrayBoilerplateDescriptionMap)                                          \
     81   V(UncompiledDataWithoutPreParsedScopeMap,                                  \
     82     uncompiled_data_without_pre_parsed_scope_map,                            \
     83     UncompiledDataWithoutPreParsedScopeMap)                                  \
     84   V(UncompiledDataWithPreParsedScopeMap,                                     \
     85     uncompiled_data_with_pre_parsed_scope_map,                               \
     86     UncompiledDataWithPreParsedScopeMap)                                     \
     87   V(UndefinedValue, undefined_value, Undefined)                              \
     88   V(WeakFixedArrayMap, weak_fixed_array_map, WeakFixedArrayMap)
     89 
     90 #define HEAP_IMMOVABLE_OBJECT_LIST(V)   \
     91   HEAP_MUTABLE_IMMOVABLE_OBJECT_LIST(V) \
     92   HEAP_IMMUTABLE_IMMOVABLE_OBJECT_LIST(V)
     93 
     94 // Returned from IteratorBuiltinsAssembler::GetIterator(). Struct is declared
     95 // here to simplify use in other generated builtins.
     96 struct IteratorRecord {
     97  public:
     98   // iteratorRecord.[[Iterator]]
     99   compiler::TNode<JSReceiver> object;
    100 
    101   // iteratorRecord.[[NextMethod]]
    102   compiler::TNode<Object> next;
    103 };
    104 
    105 #ifdef DEBUG
    106 #define CSA_CHECK(csa, x)                                        \
    107   (csa)->Check(                                                  \
    108       [&]() -> compiler::Node* {                                 \
    109         return implicit_cast<compiler::SloppyTNode<Word32T>>(x); \
    110       },                                                         \
    111       #x, __FILE__, __LINE__)
    112 #else
    113 #define CSA_CHECK(csa, x) (csa)->FastCheck(x)
    114 #endif
    115 
    116 #ifdef DEBUG
    117 // Add stringified versions to the given values, except the first. That is,
    118 // transform
    119 //   x, a, b, c, d, e, f
    120 // to
    121 //   a, "a", b, "b", c, "c", d, "d", e, "e", f, "f"
    122 //
    123 // __VA_ARGS__  is ignored to allow the caller to pass through too many
    124 // parameters, and the first element is ignored to support having no extra
    125 // values without empty __VA_ARGS__ (which cause all sorts of problems with
    126 // extra commas).
    127 #define CSA_ASSERT_STRINGIFY_EXTRA_VALUES_5(_, v1, v2, v3, v4, v5, ...) \
    128   v1, #v1, v2, #v2, v3, #v3, v4, #v4, v5, #v5
    129 
    130 // Stringify the given variable number of arguments. The arguments are trimmed
    131 // to 5 if there are too many, and padded with nullptr if there are not enough.
    132 #define CSA_ASSERT_STRINGIFY_EXTRA_VALUES(...)                                \
    133   CSA_ASSERT_STRINGIFY_EXTRA_VALUES_5(__VA_ARGS__, nullptr, nullptr, nullptr, \
    134                                       nullptr, nullptr)
    135 
    136 #define CSA_ASSERT_GET_FIRST(x, ...) (x)
    137 #define CSA_ASSERT_GET_FIRST_STR(x, ...) #x
    138 
    139 // CSA_ASSERT(csa, <condition>, <extra values to print...>)
    140 
    141 // We have to jump through some hoops to allow <extra values to print...> to be
    142 // empty.
    143 #define CSA_ASSERT(csa, ...)                                             \
    144   (csa)->Assert(                                                         \
    145       [&]() -> compiler::Node* {                                         \
    146         return implicit_cast<compiler::SloppyTNode<Word32T>>(            \
    147             EXPAND(CSA_ASSERT_GET_FIRST(__VA_ARGS__)));                  \
    148       },                                                                 \
    149       EXPAND(CSA_ASSERT_GET_FIRST_STR(__VA_ARGS__)), __FILE__, __LINE__, \
    150       CSA_ASSERT_STRINGIFY_EXTRA_VALUES(__VA_ARGS__))
    151 
    152 // CSA_ASSERT_BRANCH(csa, [](Label* ok, Label* not_ok) {...},
    153 //     <extra values to print...>)
    154 
    155 #define CSA_ASSERT_BRANCH(csa, ...)                                      \
    156   (csa)->Assert(EXPAND(CSA_ASSERT_GET_FIRST(__VA_ARGS__)),               \
    157                 EXPAND(CSA_ASSERT_GET_FIRST_STR(__VA_ARGS__)), __FILE__, \
    158                 __LINE__, CSA_ASSERT_STRINGIFY_EXTRA_VALUES(__VA_ARGS__))
    159 
    160 #define CSA_ASSERT_JS_ARGC_OP(csa, Op, op, expected)                       \
    161   (csa)->Assert(                                                           \
    162       [&]() -> compiler::Node* {                                           \
    163         compiler::Node* const argc =                                       \
    164             (csa)->Parameter(Descriptor::kJSActualArgumentsCount);         \
    165         return (csa)->Op(argc, (csa)->Int32Constant(expected));            \
    166       },                                                                   \
    167       "argc " #op " " #expected, __FILE__, __LINE__,                       \
    168       SmiFromInt32((csa)->Parameter(Descriptor::kJSActualArgumentsCount)), \
    169       "argc")
    170 
    171 #define CSA_ASSERT_JS_ARGC_EQ(csa, expected) \
    172   CSA_ASSERT_JS_ARGC_OP(csa, Word32Equal, ==, expected)
    173 
    174 #define CSA_DEBUG_INFO(name) \
    175   { #name, __FILE__, __LINE__ }
    176 #define BIND(label) Bind(label, CSA_DEBUG_INFO(label))
    177 #define VARIABLE(name, ...) \
    178   Variable name(this, CSA_DEBUG_INFO(name), __VA_ARGS__)
    179 #define VARIABLE_CONSTRUCTOR(name, ...) \
    180   name(this, CSA_DEBUG_INFO(name), __VA_ARGS__)
    181 #define TYPED_VARIABLE_DEF(type, name, ...) \
    182   TVariable<type> name(CSA_DEBUG_INFO(name), __VA_ARGS__)
    183 #else  // DEBUG
    184 #define CSA_ASSERT(csa, ...) ((void)0)
    185 #define CSA_ASSERT_BRANCH(csa, ...) ((void)0)
    186 #define CSA_ASSERT_JS_ARGC_EQ(csa, expected) ((void)0)
    187 #define BIND(label) Bind(label)
    188 #define VARIABLE(name, ...) Variable name(this, __VA_ARGS__)
    189 #define VARIABLE_CONSTRUCTOR(name, ...) name(this, __VA_ARGS__)
    190 #define TYPED_VARIABLE_DEF(type, name, ...) TVariable<type> name(__VA_ARGS__)
    191 #endif  // DEBUG
    192 
    193 #define TVARIABLE(...) EXPAND(TYPED_VARIABLE_DEF(__VA_ARGS__, this))
    194 
    195 #ifdef ENABLE_SLOW_DCHECKS
    196 #define CSA_SLOW_ASSERT(csa, ...) \
    197   if (FLAG_enable_slow_asserts) { \
    198     CSA_ASSERT(csa, __VA_ARGS__); \
    199   }
    200 #else
    201 #define CSA_SLOW_ASSERT(csa, ...) ((void)0)
    202 #endif
    203 
    204 class int31_t {
    205  public:
    206   int31_t() : value_(0) {}
    207   int31_t(int value) : value_(value) {  // NOLINT(runtime/explicit)
    208     DCHECK_EQ((value & 0x80000000) != 0, (value & 0x40000000) != 0);
    209   }
    210   int31_t& operator=(int value) {
    211     DCHECK_EQ((value & 0x80000000) != 0, (value & 0x40000000) != 0);
    212     value_ = value;
    213     return *this;
    214   }
    215   int32_t value() const { return value_; }
    216   operator int32_t() const { return value_; }
    217 
    218  private:
    219   int32_t value_;
    220 };
    221 
    222 // Provides JavaScript-specific "macro-assembler" functionality on top of the
    223 // CodeAssembler. By factoring the JavaScript-isms out of the CodeAssembler,
    224 // it's possible to add JavaScript-specific useful CodeAssembler "macros"
    225 // without modifying files in the compiler directory (and requiring a review
    226 // from a compiler directory OWNER).
    227 class V8_EXPORT_PRIVATE CodeStubAssembler : public compiler::CodeAssembler {
    228  public:
    229   using Node = compiler::Node;
    230   template <class T>
    231   using TNode = compiler::TNode<T>;
    232   template <class T>
    233   using SloppyTNode = compiler::SloppyTNode<T>;
    234 
    235   template <typename T>
    236   using LazyNode = std::function<TNode<T>()>;
    237 
    238   CodeStubAssembler(compiler::CodeAssemblerState* state);
    239 
    240   enum AllocationFlag : uint8_t {
    241     kNone = 0,
    242     kDoubleAlignment = 1,
    243     kPretenured = 1 << 1,
    244     kAllowLargeObjectAllocation = 1 << 2,
    245   };
    246 
    247   enum SlackTrackingMode { kWithSlackTracking, kNoSlackTracking };
    248 
    249   typedef base::Flags<AllocationFlag> AllocationFlags;
    250 
    251   enum ParameterMode { SMI_PARAMETERS, INTPTR_PARAMETERS };
    252 
    253   // On 32-bit platforms, there is a slight performance advantage to doing all
    254   // of the array offset/index arithmetic with SMIs, since it's possible
    255   // to save a few tag/untag operations without paying an extra expense when
    256   // calculating array offset (the smi math can be folded away) and there are
    257   // fewer live ranges. Thus only convert indices to untagged value on 64-bit
    258   // platforms.
    259   ParameterMode OptimalParameterMode() const {
    260     return Is64() ? INTPTR_PARAMETERS : SMI_PARAMETERS;
    261   }
    262 
    263   MachineRepresentation ParameterRepresentation(ParameterMode mode) const {
    264     return mode == INTPTR_PARAMETERS ? MachineType::PointerRepresentation()
    265                                      : MachineRepresentation::kTaggedSigned;
    266   }
    267 
    268   MachineRepresentation OptimalParameterRepresentation() const {
    269     return ParameterRepresentation(OptimalParameterMode());
    270   }
    271 
    272   TNode<IntPtrT> ParameterToIntPtr(Node* value, ParameterMode mode) {
    273     if (mode == SMI_PARAMETERS) value = SmiUntag(value);
    274     return UncheckedCast<IntPtrT>(value);
    275   }
    276 
    277   Node* IntPtrToParameter(SloppyTNode<IntPtrT> value, ParameterMode mode) {
    278     if (mode == SMI_PARAMETERS) return SmiTag(value);
    279     return value;
    280   }
    281 
    282   Node* Int32ToParameter(SloppyTNode<Int32T> value, ParameterMode mode) {
    283     return IntPtrToParameter(ChangeInt32ToIntPtr(value), mode);
    284   }
    285 
    286   TNode<Smi> ParameterToTagged(Node* value, ParameterMode mode) {
    287     if (mode != SMI_PARAMETERS) return SmiTag(value);
    288     return UncheckedCast<Smi>(value);
    289   }
    290 
    291   Node* TaggedToParameter(SloppyTNode<Smi> value, ParameterMode mode) {
    292     if (mode != SMI_PARAMETERS) return SmiUntag(value);
    293     return value;
    294   }
    295 
    296   TNode<Smi> TaggedToSmi(TNode<Object> value, Label* fail) {
    297     GotoIf(TaggedIsNotSmi(value), fail);
    298     return UncheckedCast<Smi>(value);
    299   }
    300 
    301   TNode<Number> TaggedToNumber(TNode<Object> value, Label* fail) {
    302     GotoIfNot(IsNumber(value), fail);
    303     return UncheckedCast<Number>(value);
    304   }
    305 
    306   TNode<HeapObject> TaggedToHeapObject(TNode<Object> value, Label* fail) {
    307     GotoIf(TaggedIsSmi(value), fail);
    308     return UncheckedCast<HeapObject>(value);
    309   }
    310 
    311   TNode<JSArray> HeapObjectToJSArray(TNode<HeapObject> heap_object,
    312                                      Label* fail) {
    313     GotoIfNot(IsJSArray(heap_object), fail);
    314     return UncheckedCast<JSArray>(heap_object);
    315   }
    316 
    317   TNode<JSArray> TaggedToFastJSArray(TNode<Context> context,
    318                                      TNode<Object> value, Label* fail) {
    319     GotoIf(TaggedIsSmi(value), fail);
    320     TNode<HeapObject> heap_object = CAST(value);
    321     GotoIfNot(IsFastJSArray(heap_object, context), fail);
    322     return UncheckedCast<JSArray>(heap_object);
    323   }
    324 
    325   TNode<JSDataView> HeapObjectToJSDataView(TNode<HeapObject> heap_object,
    326                                            Label* fail) {
    327     GotoIfNot(IsJSDataView(heap_object), fail);
    328     return CAST(heap_object);
    329   }
    330 
    331   TNode<JSReceiver> HeapObjectToCallable(TNode<HeapObject> heap_object,
    332                                          Label* fail) {
    333     GotoIfNot(IsCallable(heap_object), fail);
    334     return CAST(heap_object);
    335   }
    336 
    337   TNode<HeapNumber> UnsafeCastNumberToHeapNumber(TNode<Number> p_n) {
    338     return CAST(p_n);
    339   }
    340 
    341   TNode<FixedArrayBase> UnsafeCastObjectToFixedArrayBase(TNode<Object> p_o) {
    342     return CAST(p_o);
    343   }
    344 
    345   TNode<FixedArray> UnsafeCastObjectToFixedArray(TNode<Object> p_o) {
    346     return CAST(p_o);
    347   }
    348 
    349   TNode<FixedDoubleArray> UnsafeCastObjectToFixedDoubleArray(
    350       TNode<Object> p_o) {
    351     return CAST(p_o);
    352   }
    353 
    354   TNode<HeapNumber> UnsafeCastObjectToHeapNumber(TNode<Object> p_o) {
    355     return CAST(p_o);
    356   }
    357 
    358   TNode<HeapObject> UnsafeCastObjectToCallable(TNode<Object> p_o) {
    359     return CAST(p_o);
    360   }
    361 
    362   TNode<Smi> UnsafeCastObjectToSmi(TNode<Object> p_o) { return CAST(p_o); }
    363 
    364   TNode<Number> UnsafeCastObjectToNumber(TNode<Object> p_o) {
    365     return CAST(p_o);
    366   }
    367 
    368   TNode<HeapObject> UnsafeCastObjectToHeapObject(TNode<Object> p_o) {
    369     return CAST(p_o);
    370   }
    371 
    372   TNode<JSArray> UnsafeCastObjectToJSArray(TNode<Object> p_o) {
    373     return CAST(p_o);
    374   }
    375 
    376   TNode<FixedTypedArrayBase> UnsafeCastObjectToFixedTypedArrayBase(
    377       TNode<Object> p_o) {
    378     return CAST(p_o);
    379   }
    380 
    381   TNode<Object> UnsafeCastObjectToCompareBuiltinFn(TNode<Object> p_o) {
    382     return p_o;
    383   }
    384 
    385   TNode<Object> UnsafeCastObjectToLoadFn(TNode<Object> p_o) { return p_o; }
    386   TNode<Object> UnsafeCastObjectToStoreFn(TNode<Object> p_o) { return p_o; }
    387   TNode<Object> UnsafeCastObjectToCanUseSameAccessorFn(TNode<Object> p_o) {
    388     return p_o;
    389   }
    390 
    391   TNode<NumberDictionary> UnsafeCastObjectToNumberDictionary(
    392       TNode<Object> p_o) {
    393     return CAST(p_o);
    394   }
    395 
    396   TNode<JSReceiver> UnsafeCastObjectToJSReceiver(TNode<Object> p_o) {
    397     return CAST(p_o);
    398   }
    399 
    400   TNode<JSObject> UnsafeCastObjectToJSObject(TNode<Object> p_o) {
    401     return CAST(p_o);
    402   }
    403 
    404   TNode<Map> UnsafeCastObjectToMap(TNode<Object> p_o) { return CAST(p_o); }
    405 
    406   Node* MatchesParameterMode(Node* value, ParameterMode mode);
    407 
    408 #define PARAMETER_BINOP(OpName, IntPtrOpName, SmiOpName) \
    409   Node* OpName(Node* a, Node* b, ParameterMode mode) {   \
    410     if (mode == SMI_PARAMETERS) {                        \
    411       return SmiOpName(CAST(a), CAST(b));                \
    412     } else {                                             \
    413       DCHECK_EQ(INTPTR_PARAMETERS, mode);                \
    414       return IntPtrOpName(a, b);                         \
    415     }                                                    \
    416   }
    417   PARAMETER_BINOP(IntPtrOrSmiMin, IntPtrMin, SmiMin)
    418   PARAMETER_BINOP(IntPtrOrSmiAdd, IntPtrAdd, SmiAdd)
    419   PARAMETER_BINOP(IntPtrOrSmiSub, IntPtrSub, SmiSub)
    420   PARAMETER_BINOP(IntPtrOrSmiLessThan, IntPtrLessThan, SmiLessThan)
    421   PARAMETER_BINOP(IntPtrOrSmiLessThanOrEqual, IntPtrLessThanOrEqual,
    422                   SmiLessThanOrEqual)
    423   PARAMETER_BINOP(IntPtrOrSmiGreaterThan, IntPtrGreaterThan, SmiGreaterThan)
    424   PARAMETER_BINOP(IntPtrOrSmiGreaterThanOrEqual, IntPtrGreaterThanOrEqual,
    425                   SmiGreaterThanOrEqual)
    426   PARAMETER_BINOP(UintPtrOrSmiLessThan, UintPtrLessThan, SmiBelow)
    427   PARAMETER_BINOP(UintPtrOrSmiGreaterThanOrEqual, UintPtrGreaterThanOrEqual,
    428                   SmiAboveOrEqual)
    429 #undef PARAMETER_BINOP
    430 
    431   TNode<Object> NoContextConstant();
    432 
    433 #define HEAP_CONSTANT_ACCESSOR(rootIndexName, rootAccessorName, name) \
    434   compiler::TNode<std::remove_reference<decltype(                     \
    435       *std::declval<ReadOnlyRoots>().rootAccessorName())>::type>      \
    436       name##Constant();
    437   HEAP_IMMUTABLE_IMMOVABLE_OBJECT_LIST(HEAP_CONSTANT_ACCESSOR)
    438 #undef HEAP_CONSTANT_ACCESSOR
    439 
    440 #define HEAP_CONSTANT_ACCESSOR(rootIndexName, rootAccessorName, name) \
    441   compiler::TNode<std::remove_reference<decltype(                     \
    442       *std::declval<Heap>().rootAccessorName())>::type>               \
    443       name##Constant();
    444   HEAP_MUTABLE_IMMOVABLE_OBJECT_LIST(HEAP_CONSTANT_ACCESSOR)
    445 #undef HEAP_CONSTANT_ACCESSOR
    446 
    447 #define HEAP_CONSTANT_TEST(rootIndexName, rootAccessorName, name) \
    448   TNode<BoolT> Is##name(SloppyTNode<Object> value);               \
    449   TNode<BoolT> IsNot##name(SloppyTNode<Object> value);
    450   HEAP_IMMOVABLE_OBJECT_LIST(HEAP_CONSTANT_TEST)
    451 #undef HEAP_CONSTANT_TEST
    452 
    453   TNode<Int64T> HashSeed();
    454   TNode<Int32T> HashSeedHigh();
    455   TNode<Int32T> HashSeedLow();
    456 
    457   Node* IntPtrOrSmiConstant(int value, ParameterMode mode);
    458   TNode<Smi> LanguageModeConstant(LanguageMode mode) {
    459     return SmiConstant(static_cast<int>(mode));
    460   }
    461 
    462   bool IsIntPtrOrSmiConstantZero(Node* test, ParameterMode mode);
    463   bool TryGetIntPtrOrSmiConstantValue(Node* maybe_constant, int* value,
    464                                       ParameterMode mode);
    465 
    466   // Round the 32bits payload of the provided word up to the next power of two.
    467   TNode<IntPtrT> IntPtrRoundUpToPowerOfTwo32(TNode<IntPtrT> value);
    468   // Select the maximum of the two provided IntPtr values.
    469   TNode<IntPtrT> IntPtrMax(SloppyTNode<IntPtrT> left,
    470                            SloppyTNode<IntPtrT> right);
    471   // Select the minimum of the two provided IntPtr values.
    472   TNode<IntPtrT> IntPtrMin(SloppyTNode<IntPtrT> left,
    473                            SloppyTNode<IntPtrT> right);
    474 
    475   // Float64 operations.
    476   TNode<Float64T> Float64Ceil(SloppyTNode<Float64T> x);
    477   TNode<Float64T> Float64Floor(SloppyTNode<Float64T> x);
    478   TNode<Float64T> Float64Round(SloppyTNode<Float64T> x);
    479   TNode<Float64T> Float64RoundToEven(SloppyTNode<Float64T> x);
    480   TNode<Float64T> Float64Trunc(SloppyTNode<Float64T> x);
    481   // Select the minimum of the two provided Number values.
    482   TNode<Object> NumberMax(SloppyTNode<Object> left, SloppyTNode<Object> right);
    483   // Select the minimum of the two provided Number values.
    484   TNode<Object> NumberMin(SloppyTNode<Object> left, SloppyTNode<Object> right);
    485 
    486   // After converting an index to an integer, calculate a relative index: if
    487   // index < 0, max(length + index, 0); else min(index, length)
    488   TNode<IntPtrT> ConvertToRelativeIndex(TNode<Context> context,
    489                                         TNode<Object> index,
    490                                         TNode<IntPtrT> length);
    491 
    492   // Returns true iff the given value fits into smi range and is >= 0.
    493   TNode<BoolT> IsValidPositiveSmi(TNode<IntPtrT> value);
    494 
    495   // Tag an IntPtr as a Smi value.
    496   TNode<Smi> SmiTag(SloppyTNode<IntPtrT> value);
    497   // Untag a Smi value as an IntPtr.
    498   TNode<IntPtrT> SmiUntag(SloppyTNode<Smi> value);
    499 
    500   // Smi conversions.
    501   TNode<Float64T> SmiToFloat64(SloppyTNode<Smi> value);
    502   TNode<Smi> SmiFromIntPtr(SloppyTNode<IntPtrT> value) { return SmiTag(value); }
    503   TNode<Smi> SmiFromInt32(SloppyTNode<Int32T> value);
    504   TNode<IntPtrT> SmiToIntPtr(SloppyTNode<Smi> value) { return SmiUntag(value); }
    505   TNode<Int32T> SmiToInt32(SloppyTNode<Smi> value);
    506 
    507   // Smi operations.
    508 #define SMI_ARITHMETIC_BINOP(SmiOpName, IntPtrOpName, Int32OpName)       \
    509   TNode<Smi> SmiOpName(TNode<Smi> a, TNode<Smi> b) {                     \
    510     if (SmiValuesAre32Bits()) {                                          \
    511       return BitcastWordToTaggedSigned(                                  \
    512           IntPtrOpName(BitcastTaggedToWord(a), BitcastTaggedToWord(b))); \
    513     } else {                                                             \
    514       DCHECK(SmiValuesAre31Bits());                                      \
    515       if (kPointerSize == kInt64Size) {                                  \
    516         CSA_ASSERT(this, IsValidSmi(a));                                 \
    517         CSA_ASSERT(this, IsValidSmi(b));                                 \
    518       }                                                                  \
    519       return BitcastWordToTaggedSigned(ChangeInt32ToIntPtr(              \
    520           Int32OpName(TruncateIntPtrToInt32(BitcastTaggedToWord(a)),     \
    521                       TruncateIntPtrToInt32(BitcastTaggedToWord(b)))));  \
    522     }                                                                    \
    523   }
    524   SMI_ARITHMETIC_BINOP(SmiAdd, IntPtrAdd, Int32Add)
    525   SMI_ARITHMETIC_BINOP(SmiSub, IntPtrSub, Int32Sub)
    526   SMI_ARITHMETIC_BINOP(SmiAnd, WordAnd, Word32And)
    527   SMI_ARITHMETIC_BINOP(SmiOr, WordOr, Word32Or)
    528 #undef SMI_ARITHMETIC_BINOP
    529   TNode<Smi> SmiInc(TNode<Smi> value) { return SmiAdd(value, SmiConstant(1)); }
    530 
    531   TNode<Smi> TrySmiAdd(TNode<Smi> a, TNode<Smi> b, Label* if_overflow);
    532   TNode<Smi> TrySmiSub(TNode<Smi> a, TNode<Smi> b, Label* if_overflow);
    533 
    534   TNode<Smi> SmiShl(TNode<Smi> a, int shift) {
    535     return BitcastWordToTaggedSigned(WordShl(BitcastTaggedToWord(a), shift));
    536   }
    537 
    538   TNode<Smi> SmiShr(TNode<Smi> a, int shift) {
    539     return BitcastWordToTaggedSigned(
    540         WordAnd(WordShr(BitcastTaggedToWord(a), shift),
    541                 BitcastTaggedToWord(SmiConstant(-1))));
    542   }
    543 
    544   Node* WordOrSmiShl(Node* a, int shift, ParameterMode mode) {
    545     if (mode == SMI_PARAMETERS) {
    546       return SmiShl(CAST(a), shift);
    547     } else {
    548       DCHECK_EQ(INTPTR_PARAMETERS, mode);
    549       return WordShl(a, shift);
    550     }
    551   }
    552 
    553   Node* WordOrSmiShr(Node* a, int shift, ParameterMode mode) {
    554     if (mode == SMI_PARAMETERS) {
    555       return SmiShr(CAST(a), shift);
    556     } else {
    557       DCHECK_EQ(INTPTR_PARAMETERS, mode);
    558       return WordShr(a, shift);
    559     }
    560   }
    561 
    562 #define SMI_COMPARISON_OP(SmiOpName, IntPtrOpName, Int32OpName)            \
    563   TNode<BoolT> SmiOpName(TNode<Smi> a, TNode<Smi> b) {                     \
    564     if (SmiValuesAre32Bits()) {                                            \
    565       return IntPtrOpName(BitcastTaggedToWord(a), BitcastTaggedToWord(b)); \
    566     } else {                                                               \
    567       DCHECK(SmiValuesAre31Bits());                                        \
    568       if (kPointerSize == kInt64Size) {                                    \
    569         CSA_ASSERT(this, IsValidSmi(a));                                   \
    570         CSA_ASSERT(this, IsValidSmi(b));                                   \
    571       }                                                                    \
    572       return Int32OpName(TruncateIntPtrToInt32(BitcastTaggedToWord(a)),    \
    573                          TruncateIntPtrToInt32(BitcastTaggedToWord(b)));   \
    574     }                                                                      \
    575   }
    576   SMI_COMPARISON_OP(SmiEqual, WordEqual, Word32Equal)
    577   SMI_COMPARISON_OP(SmiNotEqual, WordNotEqual, Word32NotEqual)
    578   SMI_COMPARISON_OP(SmiAbove, UintPtrGreaterThan, Uint32GreaterThan)
    579   SMI_COMPARISON_OP(SmiAboveOrEqual, UintPtrGreaterThanOrEqual,
    580                     Uint32GreaterThanOrEqual)
    581   SMI_COMPARISON_OP(SmiBelow, UintPtrLessThan, Uint32LessThan)
    582   SMI_COMPARISON_OP(SmiLessThan, IntPtrLessThan, Int32LessThan)
    583   SMI_COMPARISON_OP(SmiLessThanOrEqual, IntPtrLessThanOrEqual,
    584                     Int32LessThanOrEqual)
    585   SMI_COMPARISON_OP(SmiGreaterThan, IntPtrGreaterThan, Int32GreaterThan)
    586   SMI_COMPARISON_OP(SmiGreaterThanOrEqual, IntPtrGreaterThanOrEqual,
    587                     Int32GreaterThanOrEqual)
    588 #undef SMI_COMPARISON_OP
    589   TNode<Smi> SmiMax(TNode<Smi> a, TNode<Smi> b);
    590   TNode<Smi> SmiMin(TNode<Smi> a, TNode<Smi> b);
    591   // Computes a % b for Smi inputs a and b; result is not necessarily a Smi.
    592   TNode<Number> SmiMod(TNode<Smi> a, TNode<Smi> b);
    593   // Computes a * b for Smi inputs a and b; result is not necessarily a Smi.
    594   TNode<Number> SmiMul(TNode<Smi> a, TNode<Smi> b);
    595   // Tries to compute dividend / divisor for Smi inputs; branching to bailout
    596   // if the division needs to be performed as a floating point operation.
    597   TNode<Smi> TrySmiDiv(TNode<Smi> dividend, TNode<Smi> divisor, Label* bailout);
    598 
    599   // Smi | HeapNumber operations.
    600   TNode<Number> NumberInc(SloppyTNode<Number> value);
    601   TNode<Number> NumberDec(SloppyTNode<Number> value);
    602   TNode<Number> NumberAdd(SloppyTNode<Number> a, SloppyTNode<Number> b);
    603   TNode<Number> NumberSub(SloppyTNode<Number> a, SloppyTNode<Number> b);
    604   void GotoIfNotNumber(Node* value, Label* is_not_number);
    605   void GotoIfNumber(Node* value, Label* is_number);
    606   TNode<Number> SmiToNumber(TNode<Smi> v) { return v; }
    607 
    608   TNode<Number> BitwiseOp(Node* left32, Node* right32, Operation bitwise_op);
    609 
    610   // Allocate an object of the given size.
    611   Node* AllocateInNewSpace(Node* size, AllocationFlags flags = kNone);
    612   Node* AllocateInNewSpace(int size, AllocationFlags flags = kNone);
    613   Node* Allocate(Node* size, AllocationFlags flags = kNone);
    614   Node* Allocate(int size, AllocationFlags flags = kNone);
    615   Node* InnerAllocate(Node* previous, int offset);
    616   Node* InnerAllocate(Node* previous, Node* offset);
    617   Node* IsRegularHeapObjectSize(Node* size);
    618 
    619   typedef std::function<void(Label*, Label*)> BranchGenerator;
    620   typedef std::function<Node*()> NodeGenerator;
    621 
    622   void Assert(const BranchGenerator& branch, const char* message = nullptr,
    623               const char* file = nullptr, int line = 0,
    624               Node* extra_node1 = nullptr, const char* extra_node1_name = "",
    625               Node* extra_node2 = nullptr, const char* extra_node2_name = "",
    626               Node* extra_node3 = nullptr, const char* extra_node3_name = "",
    627               Node* extra_node4 = nullptr, const char* extra_node4_name = "",
    628               Node* extra_node5 = nullptr, const char* extra_node5_name = "");
    629   void Assert(const NodeGenerator& condition_body,
    630               const char* message = nullptr, const char* file = nullptr,
    631               int line = 0, Node* extra_node1 = nullptr,
    632               const char* extra_node1_name = "", Node* extra_node2 = nullptr,
    633               const char* extra_node2_name = "", Node* extra_node3 = nullptr,
    634               const char* extra_node3_name = "", Node* extra_node4 = nullptr,
    635               const char* extra_node4_name = "", Node* extra_node5 = nullptr,
    636               const char* extra_node5_name = "");
    637   void Check(const BranchGenerator& branch, const char* message = nullptr,
    638              const char* file = nullptr, int line = 0,
    639              Node* extra_node1 = nullptr, const char* extra_node1_name = "",
    640              Node* extra_node2 = nullptr, const char* extra_node2_name = "",
    641              Node* extra_node3 = nullptr, const char* extra_node3_name = "",
    642              Node* extra_node4 = nullptr, const char* extra_node4_name = "",
    643              Node* extra_node5 = nullptr, const char* extra_node5_name = "");
    644   void Check(const NodeGenerator& condition_body, const char* message = nullptr,
    645              const char* file = nullptr, int line = 0,
    646              Node* extra_node1 = nullptr, const char* extra_node1_name = "",
    647              Node* extra_node2 = nullptr, const char* extra_node2_name = "",
    648              Node* extra_node3 = nullptr, const char* extra_node3_name = "",
    649              Node* extra_node4 = nullptr, const char* extra_node4_name = "",
    650              Node* extra_node5 = nullptr, const char* extra_node5_name = "");
    651   void FastCheck(TNode<BoolT> condition);
    652 
    653   // The following Call wrappers call an object according to the semantics that
    654   // one finds in the EcmaScript spec, operating on an Callable (e.g. a
    655   // JSFunction or proxy) rather than a Code object.
    656   template <class... TArgs>
    657   TNode<Object> Call(TNode<Context> context, TNode<Object> callable,
    658                      TNode<JSReceiver> receiver, TArgs... args) {
    659     return UncheckedCast<Object>(CallJS(
    660         CodeFactory::Call(isolate(), ConvertReceiverMode::kNotNullOrUndefined),
    661         context, callable, receiver, args...));
    662   }
    663   template <class... TArgs>
    664   TNode<Object> Call(TNode<Context> context, TNode<Object> callable,
    665                      TNode<Object> receiver, TArgs... args) {
    666     if (IsUndefinedConstant(receiver) || IsNullConstant(receiver)) {
    667       return UncheckedCast<Object>(CallJS(
    668           CodeFactory::Call(isolate(), ConvertReceiverMode::kNullOrUndefined),
    669           context, callable, receiver, args...));
    670     }
    671     return UncheckedCast<Object>(CallJS(CodeFactory::Call(isolate()), context,
    672                                         callable, receiver, args...));
    673   }
    674 
    675   template <class A, class F, class G>
    676   TNode<A> Select(SloppyTNode<BoolT> condition, const F& true_body,
    677                   const G& false_body) {
    678     return UncheckedCast<A>(SelectImpl(
    679         condition,
    680         [&]() -> Node* { return implicit_cast<TNode<A>>(true_body()); },
    681         [&]() -> Node* { return implicit_cast<TNode<A>>(false_body()); },
    682         MachineRepresentationOf<A>::value));
    683   }
    684 
    685   template <class A>
    686   TNode<A> SelectConstant(TNode<BoolT> condition, TNode<A> true_value,
    687                           TNode<A> false_value) {
    688     return Select<A>(condition, [=] { return true_value; },
    689                      [=] { return false_value; });
    690   }
    691 
    692   TNode<Int32T> SelectInt32Constant(SloppyTNode<BoolT> condition,
    693                                     int true_value, int false_value);
    694   TNode<IntPtrT> SelectIntPtrConstant(SloppyTNode<BoolT> condition,
    695                                       int true_value, int false_value);
    696   TNode<Oddball> SelectBooleanConstant(SloppyTNode<BoolT> condition);
    697   TNode<Smi> SelectSmiConstant(SloppyTNode<BoolT> condition, Smi* true_value,
    698                                Smi* false_value);
    699   TNode<Smi> SelectSmiConstant(SloppyTNode<BoolT> condition, int true_value,
    700                                Smi* false_value) {
    701     return SelectSmiConstant(condition, Smi::FromInt(true_value), false_value);
    702   }
    703   TNode<Smi> SelectSmiConstant(SloppyTNode<BoolT> condition, Smi* true_value,
    704                                int false_value) {
    705     return SelectSmiConstant(condition, true_value, Smi::FromInt(false_value));
    706   }
    707   TNode<Smi> SelectSmiConstant(SloppyTNode<BoolT> condition, int true_value,
    708                                int false_value) {
    709     return SelectSmiConstant(condition, Smi::FromInt(true_value),
    710                              Smi::FromInt(false_value));
    711   }
    712 
    713   TNode<Int32T> TruncateIntPtrToInt32(SloppyTNode<IntPtrT> value);
    714 
    715   // Check a value for smi-ness
    716   TNode<BoolT> TaggedIsSmi(SloppyTNode<Object> a);
    717   TNode<BoolT> TaggedIsSmi(TNode<MaybeObject> a);
    718   TNode<BoolT> TaggedIsNotSmi(SloppyTNode<Object> a);
    719   // Check that the value is a non-negative smi.
    720   TNode<BoolT> TaggedIsPositiveSmi(SloppyTNode<Object> a);
    721   // Check that a word has a word-aligned address.
    722   TNode<BoolT> WordIsWordAligned(SloppyTNode<WordT> word);
    723   TNode<BoolT> WordIsPowerOfTwo(SloppyTNode<IntPtrT> value);
    724 
    725 #if DEBUG
    726   void Bind(Label* label, AssemblerDebugInfo debug_info);
    727 #else
    728   void Bind(Label* label);
    729 #endif  // DEBUG
    730 
    731   void BranchIfSmiEqual(TNode<Smi> a, TNode<Smi> b, Label* if_true,
    732                         Label* if_false) {
    733     Branch(SmiEqual(a, b), if_true, if_false);
    734   }
    735 
    736   void BranchIfSmiLessThan(TNode<Smi> a, TNode<Smi> b, Label* if_true,
    737                            Label* if_false) {
    738     Branch(SmiLessThan(a, b), if_true, if_false);
    739   }
    740 
    741   void BranchIfSmiLessThanOrEqual(TNode<Smi> a, TNode<Smi> b, Label* if_true,
    742                                   Label* if_false) {
    743     Branch(SmiLessThanOrEqual(a, b), if_true, if_false);
    744   }
    745 
    746   void BranchIfFloat64IsNaN(Node* value, Label* if_true, Label* if_false) {
    747     Branch(Float64Equal(value, value), if_false, if_true);
    748   }
    749 
    750   // Branches to {if_true} if ToBoolean applied to {value} yields true,
    751   // otherwise goes to {if_false}.
    752   void BranchIfToBooleanIsTrue(Node* value, Label* if_true, Label* if_false);
    753 
    754   void BranchIfJSReceiver(Node* object, Label* if_true, Label* if_false);
    755 
    756   void BranchIfFastJSArray(Node* object, Node* context, Label* if_true,
    757                            Label* if_false, bool iteration_only = false);
    758   void BranchIfNotFastJSArray(Node* object, Node* context, Label* if_true,
    759                               Label* if_false) {
    760     BranchIfFastJSArray(object, context, if_false, if_true);
    761   }
    762   void BranchIfFastJSArrayForCopy(Node* object, Node* context, Label* if_true,
    763                                   Label* if_false);
    764 
    765   // Branches to {if_true} when --force-slow-path flag has been passed.
    766   // It's used for testing to ensure that slow path implementation behave
    767   // equivalent to corresponding fast paths (where applicable).
    768   //
    769   // Works only with V8_ENABLE_FORCE_SLOW_PATH compile time flag. Nop otherwise.
    770   void GotoIfForceSlowPath(Label* if_true);
    771 
    772   // Load value from current frame by given offset in bytes.
    773   Node* LoadFromFrame(int offset, MachineType rep = MachineType::AnyTagged());
    774   // Load value from current parent frame by given offset in bytes.
    775   Node* LoadFromParentFrame(int offset,
    776                             MachineType rep = MachineType::AnyTagged());
    777 
    778   // Load target function from the current JS frame.
    779   // This is an alternative way of getting the target function in addition to
    780   // Parameter(Descriptor::kJSTarget). The latter should be used near the
    781   // beginning of builtin code while the target value is still in the register
    782   // and the former should be used in slow paths in order to reduce register
    783   // pressure on the fast path.
    784   TNode<JSFunction> LoadTargetFromFrame();
    785 
    786   // Load an object pointer from a buffer that isn't in the heap.
    787   Node* LoadBufferObject(Node* buffer, int offset,
    788                          MachineType rep = MachineType::AnyTagged());
    789   // Load a field from an object on the heap.
    790   Node* LoadObjectField(SloppyTNode<HeapObject> object, int offset,
    791                         MachineType rep);
    792   template <class T, typename std::enable_if<
    793                          std::is_convertible<TNode<T>, TNode<Object>>::value,
    794                          int>::type = 0>
    795   TNode<T> LoadObjectField(TNode<HeapObject> object, int offset) {
    796     return CAST(LoadObjectField(object, offset, MachineTypeOf<T>::value));
    797   }
    798   template <class T, typename std::enable_if<
    799                          std::is_convertible<TNode<T>, TNode<UntaggedT>>::value,
    800                          int>::type = 0>
    801   TNode<T> LoadObjectField(TNode<HeapObject> object, int offset) {
    802     return UncheckedCast<T>(
    803         LoadObjectField(object, offset, MachineTypeOf<T>::value));
    804   }
    805   TNode<Object> LoadObjectField(SloppyTNode<HeapObject> object, int offset) {
    806     return UncheckedCast<Object>(
    807         LoadObjectField(object, offset, MachineType::AnyTagged()));
    808   }
    809   Node* LoadObjectField(SloppyTNode<HeapObject> object,
    810                         SloppyTNode<IntPtrT> offset, MachineType rep);
    811   TNode<Object> LoadObjectField(SloppyTNode<HeapObject> object,
    812                                 SloppyTNode<IntPtrT> offset) {
    813     return UncheckedCast<Object>(
    814         LoadObjectField(object, offset, MachineType::AnyTagged()));
    815   }
    816   // Load a SMI field and untag it.
    817   TNode<IntPtrT> LoadAndUntagObjectField(SloppyTNode<HeapObject> object,
    818                                          int offset);
    819   // Load a SMI field, untag it, and convert to Word32.
    820   TNode<Int32T> LoadAndUntagToWord32ObjectField(Node* object, int offset);
    821   // Load a SMI and untag it.
    822   TNode<IntPtrT> LoadAndUntagSmi(Node* base, int index);
    823   // Load a SMI root, untag it, and convert to Word32.
    824   TNode<Int32T> LoadAndUntagToWord32Root(Heap::RootListIndex root_index);
    825 
    826   TNode<MaybeObject> LoadMaybeWeakObjectField(SloppyTNode<HeapObject> object,
    827                                               int offset) {
    828     return UncheckedCast<MaybeObject>(
    829         LoadObjectField(object, offset, MachineType::AnyTagged()));
    830   }
    831 
    832   // Tag a smi and store it.
    833   Node* StoreAndTagSmi(Node* base, int offset, Node* value);
    834 
    835   // Load the floating point value of a HeapNumber.
    836   TNode<Float64T> LoadHeapNumberValue(SloppyTNode<HeapNumber> object);
    837   // Load the Map of an HeapObject.
    838   TNode<Map> LoadMap(SloppyTNode<HeapObject> object);
    839   // Load the instance type of an HeapObject.
    840   TNode<Int32T> LoadInstanceType(SloppyTNode<HeapObject> object);
    841   // Compare the instance the type of the object against the provided one.
    842   TNode<BoolT> HasInstanceType(SloppyTNode<HeapObject> object,
    843                                InstanceType type);
    844   TNode<BoolT> DoesntHaveInstanceType(SloppyTNode<HeapObject> object,
    845                                       InstanceType type);
    846   TNode<BoolT> TaggedDoesntHaveInstanceType(SloppyTNode<HeapObject> any_tagged,
    847                                             InstanceType type);
    848   // Load the properties backing store of a JSObject.
    849   TNode<HeapObject> LoadSlowProperties(SloppyTNode<JSObject> object);
    850   TNode<HeapObject> LoadFastProperties(SloppyTNode<JSObject> object);
    851   // Load the elements backing store of a JSObject.
    852   TNode<FixedArrayBase> LoadElements(SloppyTNode<JSObject> object);
    853   // Load the length of a JSArray instance.
    854   TNode<Number> LoadJSArrayLength(SloppyTNode<JSArray> array);
    855   // Load the length of a fast JSArray instance. Returns a positive Smi.
    856   TNode<Smi> LoadFastJSArrayLength(SloppyTNode<JSArray> array);
    857   // Load the length of a fixed array base instance.
    858   TNode<Smi> LoadFixedArrayBaseLength(SloppyTNode<FixedArrayBase> array);
    859   // Load the length of a fixed array base instance.
    860   TNode<IntPtrT> LoadAndUntagFixedArrayBaseLength(
    861       SloppyTNode<FixedArrayBase> array);
    862   // Load the length of a WeakFixedArray.
    863   TNode<Smi> LoadWeakFixedArrayLength(TNode<WeakFixedArray> array);
    864   TNode<IntPtrT> LoadAndUntagWeakFixedArrayLength(
    865       SloppyTNode<WeakFixedArray> array);
    866   // Load the length of a JSTypedArray instance.
    867   TNode<Smi> LoadTypedArrayLength(TNode<JSTypedArray> typed_array);
    868   // Load the bit field of a Map.
    869   TNode<Int32T> LoadMapBitField(SloppyTNode<Map> map);
    870   // Load bit field 2 of a map.
    871   TNode<Int32T> LoadMapBitField2(SloppyTNode<Map> map);
    872   // Load bit field 3 of a map.
    873   TNode<Uint32T> LoadMapBitField3(SloppyTNode<Map> map);
    874   // Load the instance type of a map.
    875   TNode<Int32T> LoadMapInstanceType(SloppyTNode<Map> map);
    876   // Load the ElementsKind of a map.
    877   TNode<Int32T> LoadMapElementsKind(SloppyTNode<Map> map);
    878   TNode<Int32T> LoadElementsKind(SloppyTNode<HeapObject> map);
    879   // Load the instance descriptors of a map.
    880   TNode<DescriptorArray> LoadMapDescriptors(SloppyTNode<Map> map);
    881   // Load the prototype of a map.
    882   TNode<HeapObject> LoadMapPrototype(SloppyTNode<Map> map);
    883   // Load the prototype info of a map. The result has to be checked if it is a
    884   // prototype info object or not.
    885   TNode<PrototypeInfo> LoadMapPrototypeInfo(SloppyTNode<Map> map,
    886                                             Label* if_has_no_proto_info);
    887   // Load the instance size of a Map.
    888   TNode<IntPtrT> LoadMapInstanceSizeInWords(SloppyTNode<Map> map);
    889   // Load the inobject properties start of a Map (valid only for JSObjects).
    890   TNode<IntPtrT> LoadMapInobjectPropertiesStartInWords(SloppyTNode<Map> map);
    891   // Load the constructor function index of a Map (only for primitive maps).
    892   TNode<IntPtrT> LoadMapConstructorFunctionIndex(SloppyTNode<Map> map);
    893   // Load the constructor of a Map (equivalent to Map::GetConstructor()).
    894   TNode<Object> LoadMapConstructor(SloppyTNode<Map> map);
    895   // Load the EnumLength of a Map.
    896   Node* LoadMapEnumLength(SloppyTNode<Map> map);
    897   // Load the back-pointer of a Map.
    898   TNode<Object> LoadMapBackPointer(SloppyTNode<Map> map);
    899   // Load the identity hash of a JSRececiver.
    900   TNode<IntPtrT> LoadJSReceiverIdentityHash(SloppyTNode<Object> receiver,
    901                                             Label* if_no_hash = nullptr);
    902 
    903   // This is only used on a newly allocated PropertyArray which
    904   // doesn't have an existing hash.
    905   void InitializePropertyArrayLength(Node* property_array, Node* length,
    906                                      ParameterMode mode);
    907 
    908   // Check if the map is set for slow properties.
    909   TNode<BoolT> IsDictionaryMap(SloppyTNode<Map> map);
    910 
    911   // Load the hash field of a name as an uint32 value.
    912   TNode<Uint32T> LoadNameHashField(SloppyTNode<Name> name);
    913   // Load the hash value of a name as an uint32 value.
    914   // If {if_hash_not_computed} label is specified then it also checks if
    915   // hash is actually computed.
    916   TNode<Uint32T> LoadNameHash(SloppyTNode<Name> name,
    917                               Label* if_hash_not_computed = nullptr);
    918 
    919   // Load length field of a String object as intptr_t value.
    920   TNode<IntPtrT> LoadStringLengthAsWord(SloppyTNode<String> object);
    921   // Load length field of a String object as Smi value.
    922   TNode<Smi> LoadStringLengthAsSmi(SloppyTNode<String> object);
    923   // Loads a pointer to the sequential String char array.
    924   Node* PointerToSeqStringData(Node* seq_string);
    925   // Load value field of a JSValue object.
    926   Node* LoadJSValueValue(Node* object);
    927 
    928   // Figures out whether the value of maybe_object is:
    929   // - a SMI (jump to "if_smi", "extracted" will be the SMI value)
    930   // - a cleared weak reference (jump to "if_cleared", "extracted" will be
    931   // untouched)
    932   // - a weak reference (jump to "if_weak", "extracted" will be the object
    933   // pointed to)
    934   // - a strong reference (jump to "if_strong", "extracted" will be the object
    935   // pointed to)
    936   void DispatchMaybeObject(TNode<MaybeObject> maybe_object, Label* if_smi,
    937                            Label* if_cleared, Label* if_weak, Label* if_strong,
    938                            TVariable<Object>* extracted);
    939   // See MaybeObject for semantics of these functions.
    940   TNode<BoolT> IsStrongHeapObject(TNode<MaybeObject> value);
    941   // This variant is for overzealous checking.
    942   TNode<BoolT> IsStrongHeapObject(TNode<Object> value) {
    943     return IsStrongHeapObject(ReinterpretCast<MaybeObject>(value));
    944   }
    945   TNode<HeapObject> ToStrongHeapObject(TNode<MaybeObject> value,
    946                                        Label* if_not_strong);
    947 
    948   TNode<BoolT> IsWeakOrClearedHeapObject(TNode<MaybeObject> value);
    949   TNode<BoolT> IsClearedWeakHeapObject(TNode<MaybeObject> value);
    950   TNode<BoolT> IsNotClearedWeakHeapObject(TNode<MaybeObject> value);
    951 
    952   // Removes the weak bit + asserts it was set.
    953   TNode<HeapObject> ToWeakHeapObject(TNode<MaybeObject> value);
    954 
    955   TNode<HeapObject> ToWeakHeapObject(TNode<MaybeObject> value,
    956                                      Label* if_cleared);
    957 
    958   TNode<BoolT> IsWeakReferenceTo(TNode<MaybeObject> object,
    959                                  TNode<Object> value);
    960   TNode<BoolT> IsNotWeakReferenceTo(TNode<MaybeObject> object,
    961                                     TNode<Object> value);
    962   TNode<BoolT> IsStrongReferenceTo(TNode<MaybeObject> object,
    963                                    TNode<Object> value);
    964 
    965   TNode<MaybeObject> MakeWeak(TNode<HeapObject> value);
    966 
    967   void FixedArrayBoundsCheck(TNode<FixedArrayBase> array, Node* index,
    968                              int additional_offset = 0,
    969                              ParameterMode parameter_mode = INTPTR_PARAMETERS);
    970 
    971   // Load an array element from a FixedArray / WeakFixedArray / PropertyArray.
    972   TNode<MaybeObject> LoadArrayElement(
    973       SloppyTNode<HeapObject> object, int array_header_size, Node* index,
    974       int additional_offset = 0,
    975       ParameterMode parameter_mode = INTPTR_PARAMETERS,
    976       LoadSensitivity needs_poisoning = LoadSensitivity::kSafe);
    977 
    978   // Load an array element from a FixedArray.
    979   TNode<Object> LoadFixedArrayElement(
    980       TNode<FixedArray> object, Node* index, int additional_offset = 0,
    981       ParameterMode parameter_mode = INTPTR_PARAMETERS,
    982       LoadSensitivity needs_poisoning = LoadSensitivity::kSafe);
    983 
    984   TNode<Object> LoadFixedArrayElement(TNode<FixedArray> object,
    985                                       TNode<IntPtrT> index,
    986                                       LoadSensitivity needs_poisoning) {
    987     return LoadFixedArrayElement(object, index, 0, INTPTR_PARAMETERS,
    988                                  needs_poisoning);
    989   }
    990 
    991   TNode<Object> LoadFixedArrayElement(
    992       TNode<FixedArray> object, TNode<IntPtrT> index, int additional_offset = 0,
    993       LoadSensitivity needs_poisoning = LoadSensitivity::kSafe) {
    994     return LoadFixedArrayElement(object, index, additional_offset,
    995                                  INTPTR_PARAMETERS, needs_poisoning);
    996   }
    997 
    998   TNode<Object> LoadFixedArrayElement(
    999       TNode<FixedArray> object, int index, int additional_offset = 0,
   1000       LoadSensitivity needs_poisoning = LoadSensitivity::kSafe) {
   1001     return LoadFixedArrayElement(object, IntPtrConstant(index),
   1002                                  additional_offset, INTPTR_PARAMETERS,
   1003                                  needs_poisoning);
   1004   }
   1005   TNode<Object> LoadFixedArrayElement(TNode<FixedArray> object,
   1006                                       TNode<Smi> index) {
   1007     return LoadFixedArrayElement(object, index, 0, SMI_PARAMETERS);
   1008   }
   1009 
   1010   TNode<Object> LoadPropertyArrayElement(SloppyTNode<PropertyArray> object,
   1011                                          SloppyTNode<IntPtrT> index);
   1012   TNode<IntPtrT> LoadPropertyArrayLength(TNode<PropertyArray> object);
   1013 
   1014   // Load an array element from a FixedArray / WeakFixedArray, untag it and
   1015   // return it as Word32.
   1016   TNode<Int32T> LoadAndUntagToWord32ArrayElement(
   1017       SloppyTNode<HeapObject> object, int array_header_size, Node* index,
   1018       int additional_offset = 0,
   1019       ParameterMode parameter_mode = INTPTR_PARAMETERS);
   1020 
   1021   // Load an array element from a FixedArray, untag it and return it as Word32.
   1022   TNode<Int32T> LoadAndUntagToWord32FixedArrayElement(
   1023       SloppyTNode<HeapObject> object, Node* index, int additional_offset = 0,
   1024       ParameterMode parameter_mode = INTPTR_PARAMETERS);
   1025 
   1026   TNode<Int32T> LoadAndUntagToWord32FixedArrayElement(
   1027       SloppyTNode<HeapObject> object, int index, int additional_offset = 0) {
   1028     return LoadAndUntagToWord32FixedArrayElement(
   1029         object, IntPtrConstant(index), additional_offset, INTPTR_PARAMETERS);
   1030   }
   1031 
   1032   // Load an array element from a WeakFixedArray.
   1033   TNode<MaybeObject> LoadWeakFixedArrayElement(
   1034       TNode<WeakFixedArray> object, Node* index, int additional_offset = 0,
   1035       ParameterMode parameter_mode = INTPTR_PARAMETERS,
   1036       LoadSensitivity needs_poisoning = LoadSensitivity::kSafe);
   1037 
   1038   TNode<MaybeObject> LoadWeakFixedArrayElement(
   1039       TNode<WeakFixedArray> object, int index, int additional_offset = 0,
   1040       LoadSensitivity needs_poisoning = LoadSensitivity::kSafe) {
   1041     return LoadWeakFixedArrayElement(object, IntPtrConstant(index),
   1042                                      additional_offset, INTPTR_PARAMETERS,
   1043                                      needs_poisoning);
   1044   }
   1045 
   1046   // Load an array element from a FixedDoubleArray.
   1047   TNode<Float64T> LoadFixedDoubleArrayElement(
   1048       SloppyTNode<FixedDoubleArray> object, Node* index,
   1049       MachineType machine_type, int additional_offset = 0,
   1050       ParameterMode parameter_mode = INTPTR_PARAMETERS,
   1051       Label* if_hole = nullptr);
   1052 
   1053   Node* LoadFixedDoubleArrayElement(TNode<FixedDoubleArray> object,
   1054                                     TNode<Smi> index) {
   1055     return LoadFixedDoubleArrayElement(object, index, MachineType::Float64(), 0,
   1056                                        SMI_PARAMETERS);
   1057   }
   1058 
   1059   // Load an array element from a FixedArray, FixedDoubleArray or a
   1060   // NumberDictionary (depending on the |elements_kind|) and return
   1061   // it as a tagged value. Assumes that the |index| passed a length
   1062   // check before. Bails out to |if_accessor| if the element that
   1063   // was found is an accessor, or to |if_hole| if the element at
   1064   // the given |index| is not found in |elements|.
   1065   TNode<Object> LoadFixedArrayBaseElementAsTagged(
   1066       TNode<FixedArrayBase> elements, TNode<IntPtrT> index,
   1067       TNode<Int32T> elements_kind, Label* if_accessor, Label* if_hole);
   1068 
   1069   // Load a feedback slot from a FeedbackVector.
   1070   TNode<MaybeObject> LoadFeedbackVectorSlot(
   1071       Node* object, Node* index, int additional_offset = 0,
   1072       ParameterMode parameter_mode = INTPTR_PARAMETERS);
   1073 
   1074   TNode<IntPtrT> LoadFeedbackVectorLength(TNode<FeedbackVector>);
   1075   TNode<Float64T> LoadDoubleWithHoleCheck(TNode<FixedDoubleArray> array,
   1076                                           TNode<Smi> index,
   1077                                           Label* if_hole = nullptr);
   1078 
   1079   // Load Float64 value by |base| + |offset| address. If the value is a double
   1080   // hole then jump to |if_hole|. If |machine_type| is None then only the hole
   1081   // check is generated.
   1082   TNode<Float64T> LoadDoubleWithHoleCheck(
   1083       SloppyTNode<Object> base, SloppyTNode<IntPtrT> offset, Label* if_hole,
   1084       MachineType machine_type = MachineType::Float64());
   1085   TNode<RawPtrT> LoadFixedTypedArrayBackingStore(
   1086       TNode<FixedTypedArrayBase> typed_array);
   1087   Node* LoadFixedTypedArrayElementAsTagged(
   1088       Node* data_pointer, Node* index_node, ElementsKind elements_kind,
   1089       ParameterMode parameter_mode = INTPTR_PARAMETERS);
   1090   TNode<Numeric> LoadFixedTypedArrayElementAsTagged(
   1091       TNode<WordT> data_pointer, TNode<Smi> index, TNode<Int32T> elements_kind);
   1092   // Parts of the above, factored out for readability:
   1093   Node* LoadFixedBigInt64ArrayElementAsTagged(Node* data_pointer, Node* offset);
   1094   Node* LoadFixedBigUint64ArrayElementAsTagged(Node* data_pointer,
   1095                                                Node* offset);
   1096 
   1097   void StoreFixedTypedArrayElementFromTagged(
   1098       TNode<Context> context, TNode<FixedTypedArrayBase> elements,
   1099       TNode<Object> index_node, TNode<Object> value, ElementsKind elements_kind,
   1100       ParameterMode parameter_mode);
   1101 
   1102   // Context manipulation
   1103   TNode<Object> LoadContextElement(SloppyTNode<Context> context,
   1104                                    int slot_index);
   1105   TNode<Object> LoadContextElement(SloppyTNode<Context> context,
   1106                                    SloppyTNode<IntPtrT> slot_index);
   1107   void StoreContextElement(SloppyTNode<Context> context, int slot_index,
   1108                            SloppyTNode<Object> value);
   1109   void StoreContextElement(SloppyTNode<Context> context,
   1110                            SloppyTNode<IntPtrT> slot_index,
   1111                            SloppyTNode<Object> value);
   1112   void StoreContextElementNoWriteBarrier(SloppyTNode<Context> context,
   1113                                          int slot_index,
   1114                                          SloppyTNode<Object> value);
   1115   TNode<Context> LoadNativeContext(SloppyTNode<Context> context);
   1116   // Calling this is only valid if there's a module context in the chain.
   1117   TNode<Context> LoadModuleContext(SloppyTNode<Context> context);
   1118 
   1119   void GotoIfContextElementEqual(Node* value, Node* native_context,
   1120                                  int slot_index, Label* if_equal) {
   1121     GotoIf(WordEqual(value, LoadContextElement(native_context, slot_index)),
   1122            if_equal);
   1123   }
   1124 
   1125   TNode<Map> LoadJSArrayElementsMap(ElementsKind kind,
   1126                                     SloppyTNode<Context> native_context);
   1127   TNode<Map> LoadJSArrayElementsMap(SloppyTNode<Int32T> kind,
   1128                                     SloppyTNode<Context> native_context);
   1129 
   1130   TNode<BoolT> IsGeneratorFunction(TNode<JSFunction> function);
   1131   TNode<BoolT> HasPrototypeProperty(TNode<JSFunction> function, TNode<Map> map);
   1132   void GotoIfPrototypeRequiresRuntimeLookup(TNode<JSFunction> function,
   1133                                             TNode<Map> map, Label* runtime);
   1134   // Load the "prototype" property of a JSFunction.
   1135   Node* LoadJSFunctionPrototype(Node* function, Label* if_bailout);
   1136 
   1137   Node* LoadSharedFunctionInfoBytecodeArray(Node* shared);
   1138 
   1139   void StoreObjectByteNoWriteBarrier(TNode<HeapObject> object, int offset,
   1140                                      TNode<Word32T> value);
   1141 
   1142   // Store the floating point value of a HeapNumber.
   1143   void StoreHeapNumberValue(SloppyTNode<HeapNumber> object,
   1144                             SloppyTNode<Float64T> value);
   1145   void StoreMutableHeapNumberValue(SloppyTNode<MutableHeapNumber> object,
   1146                                    SloppyTNode<Float64T> value);
   1147   // Store a field to an object on the heap.
   1148   Node* StoreObjectField(Node* object, int offset, Node* value);
   1149   Node* StoreObjectField(Node* object, Node* offset, Node* value);
   1150   Node* StoreObjectFieldNoWriteBarrier(
   1151       Node* object, int offset, Node* value,
   1152       MachineRepresentation rep = MachineRepresentation::kTagged);
   1153   Node* StoreObjectFieldNoWriteBarrier(
   1154       Node* object, Node* offset, Node* value,
   1155       MachineRepresentation rep = MachineRepresentation::kTagged);
   1156   // Store the Map of an HeapObject.
   1157   Node* StoreMap(Node* object, Node* map);
   1158   Node* StoreMapNoWriteBarrier(Node* object,
   1159                                Heap::RootListIndex map_root_index);
   1160   Node* StoreMapNoWriteBarrier(Node* object, Node* map);
   1161   Node* StoreObjectFieldRoot(Node* object, int offset,
   1162                              Heap::RootListIndex root);
   1163   // Store an array element to a FixedArray.
   1164   void StoreFixedArrayElement(
   1165       TNode<FixedArray> object, int index, SloppyTNode<Object> value,
   1166       WriteBarrierMode barrier_mode = UPDATE_WRITE_BARRIER) {
   1167     return StoreFixedArrayElement(object, IntPtrConstant(index), value,
   1168                                   barrier_mode);
   1169   }
   1170 
   1171   Node* StoreJSArrayLength(TNode<JSArray> array, TNode<Smi> length);
   1172   Node* StoreElements(TNode<Object> object, TNode<FixedArrayBase> elements);
   1173 
   1174   void StoreFixedArrayOrPropertyArrayElement(
   1175       Node* array, Node* index, Node* value,
   1176       WriteBarrierMode barrier_mode = UPDATE_WRITE_BARRIER,
   1177       int additional_offset = 0,
   1178       ParameterMode parameter_mode = INTPTR_PARAMETERS);
   1179 
   1180   void StoreFixedArrayElement(
   1181       TNode<FixedArray> array, Node* index, SloppyTNode<Object> value,
   1182       WriteBarrierMode barrier_mode = UPDATE_WRITE_BARRIER,
   1183       int additional_offset = 0,
   1184       ParameterMode parameter_mode = INTPTR_PARAMETERS) {
   1185     FixedArrayBoundsCheck(array, index, additional_offset, parameter_mode);
   1186     StoreFixedArrayOrPropertyArrayElement(array, index, value, barrier_mode,
   1187                                           additional_offset, parameter_mode);
   1188   }
   1189 
   1190   void StorePropertyArrayElement(
   1191       TNode<PropertyArray> array, Node* index, SloppyTNode<Object> value,
   1192       WriteBarrierMode barrier_mode = UPDATE_WRITE_BARRIER,
   1193       int additional_offset = 0,
   1194       ParameterMode parameter_mode = INTPTR_PARAMETERS) {
   1195     StoreFixedArrayOrPropertyArrayElement(array, index, value, barrier_mode,
   1196                                           additional_offset, parameter_mode);
   1197   }
   1198 
   1199   void StoreFixedArrayElementSmi(
   1200       TNode<FixedArray> array, TNode<Smi> index, TNode<Object> value,
   1201       WriteBarrierMode barrier_mode = UPDATE_WRITE_BARRIER) {
   1202     StoreFixedArrayElement(array, index, value, barrier_mode, 0,
   1203                            SMI_PARAMETERS);
   1204   }
   1205 
   1206   void StoreFixedDoubleArrayElement(
   1207       TNode<FixedDoubleArray> object, Node* index, TNode<Float64T> value,
   1208       ParameterMode parameter_mode = INTPTR_PARAMETERS);
   1209 
   1210   Node* StoreFeedbackVectorSlot(
   1211       Node* object, Node* index, Node* value,
   1212       WriteBarrierMode barrier_mode = UPDATE_WRITE_BARRIER,
   1213       int additional_offset = 0,
   1214       ParameterMode parameter_mode = INTPTR_PARAMETERS);
   1215 
   1216   void EnsureArrayLengthWritable(TNode<Map> map, Label* bailout);
   1217 
   1218   // EnsureArrayPushable verifies that receiver with this map is:
   1219   //   1. Is not a prototype.
   1220   //   2. Is not a dictionary.
   1221   //   3. Has a writeable length property.
   1222   // It returns ElementsKind as a node for further division into cases.
   1223   TNode<Int32T> EnsureArrayPushable(TNode<Map> map, Label* bailout);
   1224 
   1225   void TryStoreArrayElement(ElementsKind kind, ParameterMode mode,
   1226                             Label* bailout, Node* elements, Node* index,
   1227                             Node* value);
   1228   // Consumes args into the array, and returns tagged new length.
   1229   TNode<Smi> BuildAppendJSArray(ElementsKind kind, SloppyTNode<JSArray> array,
   1230                                 CodeStubArguments* args,
   1231                                 TVariable<IntPtrT>* arg_index, Label* bailout);
   1232   // Pushes value onto the end of array.
   1233   void BuildAppendJSArray(ElementsKind kind, Node* array, Node* value,
   1234                           Label* bailout);
   1235 
   1236   void StoreFieldsNoWriteBarrier(Node* start_address, Node* end_address,
   1237                                  Node* value);
   1238 
   1239   Node* AllocateCellWithValue(Node* value,
   1240                               WriteBarrierMode mode = UPDATE_WRITE_BARRIER);
   1241   Node* AllocateSmiCell(int value = 0) {
   1242     return AllocateCellWithValue(SmiConstant(value), SKIP_WRITE_BARRIER);
   1243   }
   1244 
   1245   Node* LoadCellValue(Node* cell);
   1246 
   1247   Node* StoreCellValue(Node* cell, Node* value,
   1248                        WriteBarrierMode mode = UPDATE_WRITE_BARRIER);
   1249 
   1250   // Allocate a HeapNumber without initializing its value.
   1251   TNode<HeapNumber> AllocateHeapNumber();
   1252   // Allocate a HeapNumber with a specific value.
   1253   TNode<HeapNumber> AllocateHeapNumberWithValue(SloppyTNode<Float64T> value);
   1254   TNode<HeapNumber> AllocateHeapNumberWithValue(double value) {
   1255     return AllocateHeapNumberWithValue(Float64Constant(value));
   1256   }
   1257 
   1258   // Allocate a MutableHeapNumber with a specific value.
   1259   TNode<MutableHeapNumber> AllocateMutableHeapNumberWithValue(
   1260       SloppyTNode<Float64T> value);
   1261 
   1262   // Allocate a BigInt with {length} digits. Sets the sign bit to {false}.
   1263   // Does not initialize the digits.
   1264   TNode<BigInt> AllocateBigInt(TNode<IntPtrT> length);
   1265   // Like above, but allowing custom bitfield initialization.
   1266   TNode<BigInt> AllocateRawBigInt(TNode<IntPtrT> length);
   1267   void StoreBigIntBitfield(TNode<BigInt> bigint, TNode<WordT> bitfield);
   1268   void StoreBigIntDigit(TNode<BigInt> bigint, int digit_index,
   1269                         TNode<UintPtrT> digit);
   1270   TNode<WordT> LoadBigIntBitfield(TNode<BigInt> bigint);
   1271   TNode<UintPtrT> LoadBigIntDigit(TNode<BigInt> bigint, int digit_index);
   1272 
   1273   // Allocate a SeqOneByteString with the given length.
   1274   TNode<String> AllocateSeqOneByteString(int length,
   1275                                          AllocationFlags flags = kNone);
   1276   TNode<String> AllocateSeqOneByteString(Node* context, TNode<Smi> length,
   1277                                          AllocationFlags flags = kNone);
   1278   // Allocate a SeqTwoByteString with the given length.
   1279   TNode<String> AllocateSeqTwoByteString(int length,
   1280                                          AllocationFlags flags = kNone);
   1281   TNode<String> AllocateSeqTwoByteString(Node* context, TNode<Smi> length,
   1282                                          AllocationFlags flags = kNone);
   1283 
   1284   // Allocate a SlicedOneByteString with the given length, parent and offset.
   1285   // |length| and |offset| are expected to be tagged.
   1286 
   1287   TNode<String> AllocateSlicedOneByteString(TNode<Smi> length,
   1288                                             TNode<String> parent,
   1289                                             TNode<Smi> offset);
   1290   // Allocate a SlicedTwoByteString with the given length, parent and offset.
   1291   // |length| and |offset| are expected to be tagged.
   1292   TNode<String> AllocateSlicedTwoByteString(TNode<Smi> length,
   1293                                             TNode<String> parent,
   1294                                             TNode<Smi> offset);
   1295 
   1296   // Allocate a one-byte ConsString with the given length, first and second
   1297   // parts. |length| is expected to be tagged, and |first| and |second| are
   1298   // expected to be one-byte strings.
   1299   TNode<String> AllocateOneByteConsString(TNode<Smi> length,
   1300                                           TNode<String> first,
   1301                                           TNode<String> second,
   1302                                           AllocationFlags flags = kNone);
   1303   // Allocate a two-byte ConsString with the given length, first and second
   1304   // parts. |length| is expected to be tagged, and |first| and |second| are
   1305   // expected to be two-byte strings.
   1306   TNode<String> AllocateTwoByteConsString(TNode<Smi> length,
   1307                                           TNode<String> first,
   1308                                           TNode<String> second,
   1309                                           AllocationFlags flags = kNone);
   1310 
   1311   // Allocate an appropriate one- or two-byte ConsString with the first and
   1312   // second parts specified by |left| and |right|.
   1313   TNode<String> NewConsString(Node* context, TNode<Smi> length,
   1314                               TNode<String> left, TNode<String> right,
   1315                               AllocationFlags flags = kNone);
   1316 
   1317   TNode<NameDictionary> AllocateNameDictionary(int at_least_space_for);
   1318   TNode<NameDictionary> AllocateNameDictionary(
   1319       TNode<IntPtrT> at_least_space_for);
   1320   TNode<NameDictionary> AllocateNameDictionaryWithCapacity(
   1321       TNode<IntPtrT> capacity);
   1322   TNode<NameDictionary> CopyNameDictionary(TNode<NameDictionary> dictionary,
   1323                                            Label* large_object_fallback);
   1324 
   1325   template <typename CollectionType>
   1326   Node* AllocateOrderedHashTable();
   1327 
   1328   // Builds code that finds OrderedHashTable entry for a key with hash code
   1329   // {hash} with using the comparison code generated by {key_compare}. The code
   1330   // jumps to {entry_found} if the key is found, or to {not_found} if the key
   1331   // was not found. In the {entry_found} branch, the variable
   1332   // entry_start_position will be bound to the index of the entry (relative to
   1333   // OrderedHashTable::kHashTableStartIndex).
   1334   //
   1335   // The {CollectionType} template parameter stands for the particular instance
   1336   // of OrderedHashTable, it should be OrderedHashMap or OrderedHashSet.
   1337   template <typename CollectionType>
   1338   void FindOrderedHashTableEntry(
   1339       Node* table, Node* hash,
   1340       std::function<void(Node*, Label*, Label*)> key_compare,
   1341       Variable* entry_start_position, Label* entry_found, Label* not_found);
   1342 
   1343   template <typename CollectionType>
   1344   TNode<CollectionType> AllocateSmallOrderedHashTable(TNode<IntPtrT> capacity);
   1345 
   1346   Node* AllocateStruct(Node* map, AllocationFlags flags = kNone);
   1347   void InitializeStructBody(Node* object, Node* map, Node* size,
   1348                             int start_offset = Struct::kHeaderSize);
   1349 
   1350   Node* AllocateJSObjectFromMap(
   1351       Node* map, Node* properties = nullptr, Node* elements = nullptr,
   1352       AllocationFlags flags = kNone,
   1353       SlackTrackingMode slack_tracking_mode = kNoSlackTracking);
   1354 
   1355   void InitializeJSObjectFromMap(
   1356       Node* object, Node* map, Node* instance_size, Node* properties = nullptr,
   1357       Node* elements = nullptr,
   1358       SlackTrackingMode slack_tracking_mode = kNoSlackTracking);
   1359 
   1360   void InitializeJSObjectBodyWithSlackTracking(Node* object, Node* map,
   1361                                                Node* instance_size);
   1362   void InitializeJSObjectBodyNoSlackTracking(
   1363       Node* object, Node* map, Node* instance_size,
   1364       int start_offset = JSObject::kHeaderSize);
   1365 
   1366   // Allocate a JSArray without elements and initialize the header fields.
   1367   Node* AllocateUninitializedJSArrayWithoutElements(
   1368       Node* array_map, Node* length, Node* allocation_site = nullptr);
   1369   // Allocate and return a JSArray with initialized header fields and its
   1370   // uninitialized elements.
   1371   // The ParameterMode argument is only used for the capacity parameter.
   1372   std::pair<Node*, Node*> AllocateUninitializedJSArrayWithElements(
   1373       ElementsKind kind, Node* array_map, Node* length, Node* allocation_site,
   1374       Node* capacity, ParameterMode capacity_mode = INTPTR_PARAMETERS);
   1375   // Allocate a JSArray and fill elements with the hole.
   1376   // The ParameterMode argument is only used for the capacity parameter.
   1377   Node* AllocateJSArray(ElementsKind kind, Node* array_map, Node* capacity,
   1378                         Node* length, Node* allocation_site = nullptr,
   1379                         ParameterMode capacity_mode = INTPTR_PARAMETERS);
   1380 
   1381   Node* AllocateJSArray(ElementsKind kind, TNode<Map> array_map,
   1382                         TNode<Smi> capacity, TNode<Smi> length) {
   1383     return AllocateJSArray(kind, array_map, capacity, length, nullptr,
   1384                            SMI_PARAMETERS);
   1385   }
   1386 
   1387   Node* AllocateJSArray(ElementsKind kind, TNode<Map> array_map,
   1388                         TNode<IntPtrT> capacity, TNode<Smi> length) {
   1389     return AllocateJSArray(kind, array_map, capacity, length, nullptr,
   1390                            INTPTR_PARAMETERS);
   1391   }
   1392 
   1393   Node* CloneFastJSArray(Node* context, Node* array,
   1394                          ParameterMode mode = INTPTR_PARAMETERS,
   1395                          Node* allocation_site = nullptr);
   1396 
   1397   Node* ExtractFastJSArray(Node* context, Node* array, Node* begin, Node* count,
   1398                            ParameterMode mode = INTPTR_PARAMETERS,
   1399                            Node* capacity = nullptr,
   1400                            Node* allocation_site = nullptr);
   1401 
   1402   TNode<FixedArrayBase> AllocateFixedArray(
   1403       ElementsKind kind, Node* capacity, ParameterMode mode = INTPTR_PARAMETERS,
   1404       AllocationFlags flags = kNone,
   1405       SloppyTNode<Map> fixed_array_map = nullptr);
   1406 
   1407   TNode<FixedArrayBase> AllocateFixedArray(
   1408       ElementsKind kind, TNode<IntPtrT> capacity, AllocationFlags flags,
   1409       SloppyTNode<Map> fixed_array_map = nullptr) {
   1410     return AllocateFixedArray(kind, capacity, INTPTR_PARAMETERS, flags,
   1411                               fixed_array_map);
   1412   }
   1413 
   1414   TNode<FixedArray> AllocateZeroedFixedArray(TNode<IntPtrT> capacity) {
   1415     TNode<FixedArray> result = UncheckedCast<FixedArray>(
   1416         AllocateFixedArray(PACKED_ELEMENTS, capacity,
   1417                            AllocationFlag::kAllowLargeObjectAllocation));
   1418     FillFixedArrayWithSmiZero(result, capacity);
   1419     return result;
   1420   }
   1421 
   1422   TNode<FixedDoubleArray> AllocateZeroedFixedDoubleArray(
   1423       TNode<IntPtrT> capacity) {
   1424     TNode<FixedDoubleArray> result = UncheckedCast<FixedDoubleArray>(
   1425         AllocateFixedArray(FLOAT64_ELEMENTS, capacity,
   1426                            AllocationFlag::kAllowLargeObjectAllocation));
   1427     FillFixedDoubleArrayWithZero(result, capacity);
   1428     return result;
   1429   }
   1430 
   1431   Node* AllocatePropertyArray(Node* capacity,
   1432                               ParameterMode mode = INTPTR_PARAMETERS,
   1433                               AllocationFlags flags = kNone);
   1434 
   1435   // Perform CreateArrayIterator (ES #sec-createarrayiterator).
   1436   TNode<JSArrayIterator> CreateArrayIterator(TNode<Context> context,
   1437                                              TNode<Object> object,
   1438                                              IterationKind mode);
   1439 
   1440   Node* AllocateJSIteratorResult(Node* context, Node* value, Node* done);
   1441   Node* AllocateJSIteratorResultForEntry(Node* context, Node* key, Node* value);
   1442 
   1443   Node* ArraySpeciesCreate(TNode<Context> context, TNode<Object> originalArray,
   1444                            TNode<Number> len);
   1445 
   1446   void FillFixedArrayWithValue(ElementsKind kind, Node* array, Node* from_index,
   1447                                Node* to_index,
   1448                                Heap::RootListIndex value_root_index,
   1449                                ParameterMode mode = INTPTR_PARAMETERS);
   1450 
   1451   // Uses memset to effectively initialize the given FixedArray with zeroes.
   1452   void FillFixedArrayWithSmiZero(TNode<FixedArray> array,
   1453                                  TNode<IntPtrT> length);
   1454   void FillFixedDoubleArrayWithZero(TNode<FixedDoubleArray> array,
   1455                                     TNode<IntPtrT> length);
   1456 
   1457   void FillPropertyArrayWithUndefined(Node* array, Node* from_index,
   1458                                       Node* to_index,
   1459                                       ParameterMode mode = INTPTR_PARAMETERS);
   1460 
   1461   void CopyPropertyArrayValues(
   1462       Node* from_array, Node* to_array, Node* length,
   1463       WriteBarrierMode barrier_mode = UPDATE_WRITE_BARRIER,
   1464       ParameterMode mode = INTPTR_PARAMETERS);
   1465 
   1466   // Copies all elements from |from_array| of |length| size to
   1467   // |to_array| of the same size respecting the elements kind.
   1468   void CopyFixedArrayElements(
   1469       ElementsKind kind, Node* from_array, Node* to_array, Node* length,
   1470       WriteBarrierMode barrier_mode = UPDATE_WRITE_BARRIER,
   1471       ParameterMode mode = INTPTR_PARAMETERS) {
   1472     CopyFixedArrayElements(kind, from_array, kind, to_array,
   1473                            IntPtrOrSmiConstant(0, mode), length, length,
   1474                            barrier_mode, mode);
   1475   }
   1476 
   1477   // Copies |element_count| elements from |from_array| starting from element
   1478   // zero to |to_array| of |capacity| size respecting both array's elements
   1479   // kinds.
   1480   void CopyFixedArrayElements(
   1481       ElementsKind from_kind, Node* from_array, ElementsKind to_kind,
   1482       Node* to_array, Node* element_count, Node* capacity,
   1483       WriteBarrierMode barrier_mode = UPDATE_WRITE_BARRIER,
   1484       ParameterMode mode = INTPTR_PARAMETERS) {
   1485     CopyFixedArrayElements(from_kind, from_array, to_kind, to_array,
   1486                            IntPtrOrSmiConstant(0, mode), element_count,
   1487                            capacity, barrier_mode, mode);
   1488   }
   1489 
   1490   // Copies |element_count| elements from |from_array| starting from element
   1491   // |first_element| to |to_array| of |capacity| size respecting both array's
   1492   // elements kinds.
   1493   void CopyFixedArrayElements(
   1494       ElementsKind from_kind, Node* from_array, ElementsKind to_kind,
   1495       Node* to_array, Node* first_element, Node* element_count, Node* capacity,
   1496       WriteBarrierMode barrier_mode = UPDATE_WRITE_BARRIER,
   1497       ParameterMode mode = INTPTR_PARAMETERS);
   1498 
   1499   void CopyFixedArrayElements(
   1500       ElementsKind from_kind, TNode<FixedArrayBase> from_array,
   1501       ElementsKind to_kind, TNode<FixedArrayBase> to_array,
   1502       TNode<Smi> first_element, TNode<Smi> element_count, TNode<Smi> capacity,
   1503       WriteBarrierMode barrier_mode = UPDATE_WRITE_BARRIER) {
   1504     CopyFixedArrayElements(from_kind, from_array, to_kind, to_array,
   1505                            first_element, element_count, capacity, barrier_mode,
   1506                            SMI_PARAMETERS);
   1507   }
   1508 
   1509   TNode<FixedArray> HeapObjectToFixedArray(TNode<HeapObject> base,
   1510                                            Label* cast_fail);
   1511 
   1512   TNode<FixedDoubleArray> HeapObjectToFixedDoubleArray(TNode<HeapObject> base,
   1513                                                        Label* cast_fail) {
   1514     GotoIf(WordNotEqual(LoadMap(base),
   1515                         LoadRoot(Heap::kFixedDoubleArrayMapRootIndex)),
   1516            cast_fail);
   1517     return UncheckedCast<FixedDoubleArray>(base);
   1518   }
   1519 
   1520   enum class ExtractFixedArrayFlag {
   1521     kFixedArrays = 1,
   1522     kFixedDoubleArrays = 2,
   1523     kDontCopyCOW = 4,
   1524     kNewSpaceAllocationOnly = 8,
   1525     kAllFixedArrays = kFixedArrays | kFixedDoubleArrays,
   1526     kAllFixedArraysDontCopyCOW = kAllFixedArrays | kDontCopyCOW
   1527   };
   1528 
   1529   typedef base::Flags<ExtractFixedArrayFlag> ExtractFixedArrayFlags;
   1530 
   1531   // Copy a portion of an existing FixedArray or FixedDoubleArray into a new
   1532   // FixedArray, including special appropriate handling for empty arrays and COW
   1533   // arrays.
   1534   //
   1535   // * |source| is either a FixedArray or FixedDoubleArray from which to copy
   1536   // elements.
   1537   // * |first| is the starting element index to copy from, if nullptr is passed
   1538   // then index zero is used by default.
   1539   // * |count| is the number of elements to copy out of the source array
   1540   // starting from and including the element indexed by |start|. If |count| is
   1541   // nullptr, then all of the elements from |start| to the end of |source| are
   1542   // copied.
   1543   // * |capacity| determines the size of the allocated result array, with
   1544   // |capacity| >= |count|. If |capacity| is nullptr, then |count| is used as
   1545   // the destination array's capacity.
   1546   // * |extract_flags| determines whether FixedArrays, FixedDoubleArrays or both
   1547   // are detected and copied. Although it's always correct to pass
   1548   // kAllFixedArrays, the generated code is more compact and efficient if the
   1549   // caller can specify whether only FixedArrays or FixedDoubleArrays will be
   1550   // passed as the |source| parameter.
   1551   // * |parameter_mode| determines the parameter mode of |first|, |count| and
   1552   // |capacity|.
   1553   TNode<FixedArrayBase> ExtractFixedArray(
   1554       Node* source, Node* first, Node* count = nullptr,
   1555       Node* capacity = nullptr,
   1556       ExtractFixedArrayFlags extract_flags =
   1557           ExtractFixedArrayFlag::kAllFixedArrays,
   1558       ParameterMode parameter_mode = INTPTR_PARAMETERS);
   1559 
   1560   TNode<FixedArrayBase> ExtractFixedArray(
   1561       TNode<FixedArrayBase> source, TNode<Smi> first, TNode<Smi> count,
   1562       TNode<Smi> capacity,
   1563       ExtractFixedArrayFlags extract_flags =
   1564           ExtractFixedArrayFlag::kAllFixedArrays) {
   1565     return ExtractFixedArray(source, first, count, capacity, extract_flags,
   1566                              SMI_PARAMETERS);
   1567   }
   1568 
   1569   // Copy the entire contents of a FixedArray or FixedDoubleArray to a new
   1570   // array, including special appropriate handling for empty arrays and COW
   1571   // arrays.
   1572   //
   1573   // * |source| is either a FixedArray or FixedDoubleArray from which to copy
   1574   // elements.
   1575   // * |extract_flags| determines whether FixedArrays, FixedDoubleArrays or both
   1576   // are detected and copied. Although it's always correct to pass
   1577   // kAllFixedArrays, the generated code is more compact and efficient if the
   1578   // caller can specify whether only FixedArrays or FixedDoubleArrays will be
   1579   // passed as the |source| parameter.
   1580   Node* CloneFixedArray(Node* source,
   1581                         ExtractFixedArrayFlags flags =
   1582                             ExtractFixedArrayFlag::kAllFixedArraysDontCopyCOW) {
   1583     ParameterMode mode = OptimalParameterMode();
   1584     return ExtractFixedArray(source, IntPtrOrSmiConstant(0, mode), nullptr,
   1585                              nullptr, flags, mode);
   1586   }
   1587 
   1588   // Copies |character_count| elements from |from_string| to |to_string|
   1589   // starting at the |from_index|'th character. |from_string| and |to_string|
   1590   // can either be one-byte strings or two-byte strings, although if
   1591   // |from_string| is two-byte, then |to_string| must be two-byte.
   1592   // |from_index|, |to_index| and |character_count| must be intptr_ts s.t. 0 <=
   1593   // |from_index| <= |from_index| + |character_count| <= from_string.length and
   1594   // 0 <= |to_index| <= |to_index| + |character_count| <= to_string.length.
   1595   void CopyStringCharacters(Node* from_string, Node* to_string,
   1596                             TNode<IntPtrT> from_index, TNode<IntPtrT> to_index,
   1597                             TNode<IntPtrT> character_count,
   1598                             String::Encoding from_encoding,
   1599                             String::Encoding to_encoding);
   1600 
   1601   // Loads an element from |array| of |from_kind| elements by given |offset|
   1602   // (NOTE: not index!), does a hole check if |if_hole| is provided and
   1603   // converts the value so that it becomes ready for storing to array of
   1604   // |to_kind| elements.
   1605   Node* LoadElementAndPrepareForStore(Node* array, Node* offset,
   1606                                       ElementsKind from_kind,
   1607                                       ElementsKind to_kind, Label* if_hole);
   1608 
   1609   Node* CalculateNewElementsCapacity(Node* old_capacity,
   1610                                      ParameterMode mode = INTPTR_PARAMETERS);
   1611 
   1612   // Tries to grow the |elements| array of given |object| to store the |key|
   1613   // or bails out if the growing gap is too big. Returns new elements.
   1614   Node* TryGrowElementsCapacity(Node* object, Node* elements, ElementsKind kind,
   1615                                 Node* key, Label* bailout);
   1616 
   1617   // Tries to grow the |capacity|-length |elements| array of given |object|
   1618   // to store the |key| or bails out if the growing gap is too big. Returns
   1619   // new elements.
   1620   Node* TryGrowElementsCapacity(Node* object, Node* elements, ElementsKind kind,
   1621                                 Node* key, Node* capacity, ParameterMode mode,
   1622                                 Label* bailout);
   1623 
   1624   // Grows elements capacity of given object. Returns new elements.
   1625   Node* GrowElementsCapacity(Node* object, Node* elements,
   1626                              ElementsKind from_kind, ElementsKind to_kind,
   1627                              Node* capacity, Node* new_capacity,
   1628                              ParameterMode mode, Label* bailout);
   1629 
   1630   // Given a need to grow by |growth|, allocate an appropriate new capacity
   1631   // if necessary, and return a new elements FixedArray object. Label |bailout|
   1632   // is followed for allocation failure.
   1633   void PossiblyGrowElementsCapacity(ParameterMode mode, ElementsKind kind,
   1634                                     Node* array, Node* length,
   1635                                     Variable* var_elements, Node* growth,
   1636                                     Label* bailout);
   1637 
   1638   // Allocation site manipulation
   1639   void InitializeAllocationMemento(Node* base_allocation,
   1640                                    Node* base_allocation_size,
   1641                                    Node* allocation_site);
   1642 
   1643   Node* TryTaggedToFloat64(Node* value, Label* if_valueisnotnumber);
   1644   Node* TruncateTaggedToFloat64(Node* context, Node* value);
   1645   Node* TruncateTaggedToWord32(Node* context, Node* value);
   1646   void TaggedToWord32OrBigInt(Node* context, Node* value, Label* if_number,
   1647                               Variable* var_word32, Label* if_bigint,
   1648                               Variable* var_bigint);
   1649   void TaggedToWord32OrBigIntWithFeedback(
   1650       Node* context, Node* value, Label* if_number, Variable* var_word32,
   1651       Label* if_bigint, Variable* var_bigint, Variable* var_feedback);
   1652 
   1653   // Truncate the floating point value of a HeapNumber to an Int32.
   1654   Node* TruncateHeapNumberValueToWord32(Node* object);
   1655 
   1656   // Conversions.
   1657   void TryHeapNumberToSmi(TNode<HeapNumber> number, TVariable<Smi>& output,
   1658                           Label* if_smi);
   1659   void TryFloat64ToSmi(TNode<Float64T> number, TVariable<Smi>& output,
   1660                        Label* if_smi);
   1661   TNode<Number> ChangeFloat64ToTagged(SloppyTNode<Float64T> value);
   1662   TNode<Number> ChangeInt32ToTagged(SloppyTNode<Int32T> value);
   1663   TNode<Number> ChangeUint32ToTagged(SloppyTNode<Uint32T> value);
   1664   TNode<Uint32T> ChangeNumberToUint32(TNode<Number> value);
   1665   TNode<Float64T> ChangeNumberToFloat64(SloppyTNode<Number> value);
   1666   TNode<UintPtrT> ChangeNonnegativeNumberToUintPtr(TNode<Number> value);
   1667 
   1668   void TaggedToNumeric(Node* context, Node* value, Label* done,
   1669                        Variable* var_numeric);
   1670   void TaggedToNumericWithFeedback(Node* context, Node* value, Label* done,
   1671                                    Variable* var_numeric,
   1672                                    Variable* var_feedback);
   1673 
   1674   TNode<WordT> TimesPointerSize(SloppyTNode<WordT> value);
   1675   TNode<IntPtrT> TimesPointerSize(TNode<IntPtrT> value) {
   1676     return Signed(TimesPointerSize(implicit_cast<TNode<WordT>>(value)));
   1677   }
   1678   TNode<UintPtrT> TimesPointerSize(TNode<UintPtrT> value) {
   1679     return Unsigned(TimesPointerSize(implicit_cast<TNode<WordT>>(value)));
   1680   }
   1681   TNode<WordT> TimesDoubleSize(SloppyTNode<WordT> value);
   1682   TNode<UintPtrT> TimesDoubleSize(TNode<UintPtrT> value) {
   1683     return Unsigned(TimesDoubleSize(implicit_cast<TNode<WordT>>(value)));
   1684   }
   1685   TNode<IntPtrT> TimesDoubleSize(TNode<IntPtrT> value) {
   1686     return Signed(TimesDoubleSize(implicit_cast<TNode<WordT>>(value)));
   1687   }
   1688 
   1689   // Type conversions.
   1690   // Throws a TypeError for {method_name} if {value} is not coercible to Object,
   1691   // or returns the {value} converted to a String otherwise.
   1692   TNode<String> ToThisString(Node* context, Node* value,
   1693                              char const* method_name);
   1694   // Throws a TypeError for {method_name} if {value} is neither of the given
   1695   // {primitive_type} nor a JSValue wrapping a value of {primitive_type}, or
   1696   // returns the {value} (or wrapped value) otherwise.
   1697   Node* ToThisValue(Node* context, Node* value, PrimitiveType primitive_type,
   1698                     char const* method_name);
   1699 
   1700   // Throws a TypeError for {method_name} if {value} is not of the given
   1701   // instance type. Returns {value}'s map.
   1702   Node* ThrowIfNotInstanceType(Node* context, Node* value,
   1703                                InstanceType instance_type,
   1704                                char const* method_name);
   1705   // Throws a TypeError for {method_name} if {value} is not a JSReceiver.
   1706   // Returns the {value}'s map.
   1707   Node* ThrowIfNotJSReceiver(Node* context, Node* value,
   1708                              MessageTemplate::Template msg_template,
   1709                              const char* method_name = nullptr);
   1710 
   1711   void ThrowRangeError(Node* context, MessageTemplate::Template message,
   1712                        Node* arg0 = nullptr, Node* arg1 = nullptr,
   1713                        Node* arg2 = nullptr);
   1714   void ThrowTypeError(Node* context, MessageTemplate::Template message,
   1715                       char const* arg0 = nullptr, char const* arg1 = nullptr);
   1716   void ThrowTypeError(Node* context, MessageTemplate::Template message,
   1717                       Node* arg0, Node* arg1 = nullptr, Node* arg2 = nullptr);
   1718 
   1719   // Type checks.
   1720   // Check whether the map is for an object with special properties, such as a
   1721   // JSProxy or an object with interceptors.
   1722   TNode<BoolT> InstanceTypeEqual(SloppyTNode<Int32T> instance_type, int type);
   1723   TNode<BoolT> IsAccessorInfo(SloppyTNode<HeapObject> object);
   1724   TNode<BoolT> IsAccessorPair(SloppyTNode<HeapObject> object);
   1725   TNode<BoolT> IsAllocationSite(SloppyTNode<HeapObject> object);
   1726   TNode<BoolT> IsAnyHeapNumber(SloppyTNode<HeapObject> object);
   1727   TNode<BoolT> IsNoElementsProtectorCellInvalid();
   1728   TNode<BoolT> IsBigIntInstanceType(SloppyTNode<Int32T> instance_type);
   1729   TNode<BoolT> IsBigInt(SloppyTNode<HeapObject> object);
   1730   TNode<BoolT> IsBoolean(SloppyTNode<HeapObject> object);
   1731   TNode<BoolT> IsCallableMap(SloppyTNode<Map> map);
   1732   TNode<BoolT> IsCallable(SloppyTNode<HeapObject> object);
   1733   TNode<BoolT> TaggedIsCallable(TNode<Object> object);
   1734   TNode<BoolT> IsCell(SloppyTNode<HeapObject> object);
   1735   TNode<BoolT> IsCode(SloppyTNode<HeapObject> object);
   1736   TNode<BoolT> IsConsStringInstanceType(SloppyTNode<Int32T> instance_type);
   1737   TNode<BoolT> IsConstructorMap(SloppyTNode<Map> map);
   1738   TNode<BoolT> IsConstructor(SloppyTNode<HeapObject> object);
   1739   TNode<BoolT> IsDeprecatedMap(SloppyTNode<Map> map);
   1740   TNode<BoolT> IsNameDictionary(SloppyTNode<HeapObject> object);
   1741   TNode<BoolT> IsGlobalDictionary(SloppyTNode<HeapObject> object);
   1742   TNode<BoolT> IsExtensibleMap(SloppyTNode<Map> map);
   1743   TNode<BoolT> IsExternalStringInstanceType(SloppyTNode<Int32T> instance_type);
   1744   TNode<BoolT> IsFastJSArray(SloppyTNode<Object> object,
   1745                              SloppyTNode<Context> context);
   1746   TNode<BoolT> IsFastJSArrayWithNoCustomIteration(TNode<Object> object,
   1747                                                   TNode<Context> context);
   1748   TNode<BoolT> IsFeedbackCell(SloppyTNode<HeapObject> object);
   1749   TNode<BoolT> IsFeedbackVector(SloppyTNode<HeapObject> object);
   1750   TNode<BoolT> IsContext(SloppyTNode<HeapObject> object);
   1751   TNode<BoolT> IsFixedArray(SloppyTNode<HeapObject> object);
   1752   TNode<BoolT> IsFixedArraySubclass(SloppyTNode<HeapObject> object);
   1753   TNode<BoolT> IsFixedArrayWithKind(SloppyTNode<HeapObject> object,
   1754                                     ElementsKind kind);
   1755   TNode<BoolT> IsFixedArrayWithKindOrEmpty(SloppyTNode<HeapObject> object,
   1756                                            ElementsKind kind);
   1757   TNode<BoolT> IsFixedDoubleArray(SloppyTNode<HeapObject> object);
   1758   TNode<BoolT> IsFixedTypedArray(SloppyTNode<HeapObject> object);
   1759   TNode<BoolT> IsFunctionWithPrototypeSlotMap(SloppyTNode<Map> map);
   1760   TNode<BoolT> IsHashTable(SloppyTNode<HeapObject> object);
   1761   TNode<BoolT> IsEphemeronHashTable(SloppyTNode<HeapObject> object);
   1762   TNode<BoolT> IsHeapNumber(SloppyTNode<HeapObject> object);
   1763   TNode<BoolT> IsIndirectStringInstanceType(SloppyTNode<Int32T> instance_type);
   1764   TNode<BoolT> IsJSArrayBuffer(SloppyTNode<HeapObject> object);
   1765   TNode<BoolT> IsJSDataView(TNode<HeapObject> object);
   1766   TNode<BoolT> IsJSArrayInstanceType(SloppyTNode<Int32T> instance_type);
   1767   TNode<BoolT> IsJSArrayMap(SloppyTNode<Map> map);
   1768   TNode<BoolT> IsJSArray(SloppyTNode<HeapObject> object);
   1769   TNode<BoolT> IsJSArrayIterator(SloppyTNode<HeapObject> object);
   1770   TNode<BoolT> IsJSAsyncGeneratorObject(SloppyTNode<HeapObject> object);
   1771   TNode<BoolT> IsJSFunctionInstanceType(SloppyTNode<Int32T> instance_type);
   1772   TNode<BoolT> IsAllocationSiteInstanceType(SloppyTNode<Int32T> instance_type);
   1773   TNode<BoolT> IsJSFunctionMap(SloppyTNode<Map> map);
   1774   TNode<BoolT> IsJSFunction(SloppyTNode<HeapObject> object);
   1775   TNode<BoolT> IsJSGeneratorObject(SloppyTNode<HeapObject> object);
   1776   TNode<BoolT> IsJSGlobalProxyInstanceType(SloppyTNode<Int32T> instance_type);
   1777   TNode<BoolT> IsJSGlobalProxy(SloppyTNode<HeapObject> object);
   1778   TNode<BoolT> IsJSObjectInstanceType(SloppyTNode<Int32T> instance_type);
   1779   TNode<BoolT> IsJSObjectMap(SloppyTNode<Map> map);
   1780   TNode<BoolT> IsJSObject(SloppyTNode<HeapObject> object);
   1781   TNode<BoolT> IsJSPromiseMap(SloppyTNode<Map> map);
   1782   TNode<BoolT> IsJSPromise(SloppyTNode<HeapObject> object);
   1783   TNode<BoolT> IsJSProxy(SloppyTNode<HeapObject> object);
   1784   TNode<BoolT> IsJSReceiverInstanceType(SloppyTNode<Int32T> instance_type);
   1785   TNode<BoolT> IsJSReceiverMap(SloppyTNode<Map> map);
   1786   TNode<BoolT> IsJSReceiver(SloppyTNode<HeapObject> object);
   1787   TNode<BoolT> IsJSRegExp(SloppyTNode<HeapObject> object);
   1788   TNode<BoolT> IsJSTypedArray(SloppyTNode<HeapObject> object);
   1789   TNode<BoolT> IsJSValueInstanceType(SloppyTNode<Int32T> instance_type);
   1790   TNode<BoolT> IsJSValueMap(SloppyTNode<Map> map);
   1791   TNode<BoolT> IsJSValue(SloppyTNode<HeapObject> object);
   1792   TNode<BoolT> IsMap(SloppyTNode<HeapObject> object);
   1793   TNode<BoolT> IsMutableHeapNumber(SloppyTNode<HeapObject> object);
   1794   TNode<BoolT> IsName(SloppyTNode<HeapObject> object);
   1795   TNode<BoolT> IsNativeContext(SloppyTNode<HeapObject> object);
   1796   TNode<BoolT> IsNullOrJSReceiver(SloppyTNode<HeapObject> object);
   1797   TNode<BoolT> IsNullOrUndefined(SloppyTNode<Object> object);
   1798   TNode<BoolT> IsNumberDictionary(SloppyTNode<HeapObject> object);
   1799   TNode<BoolT> IsOneByteStringInstanceType(SloppyTNode<Int32T> instance_type);
   1800   TNode<BoolT> IsPrimitiveInstanceType(SloppyTNode<Int32T> instance_type);
   1801   TNode<BoolT> IsPrivateSymbol(SloppyTNode<HeapObject> object);
   1802   TNode<BoolT> IsPromiseCapability(SloppyTNode<HeapObject> object);
   1803   TNode<BoolT> IsPropertyArray(SloppyTNode<HeapObject> object);
   1804   TNode<BoolT> IsPropertyCell(SloppyTNode<HeapObject> object);
   1805   TNode<BoolT> IsPrototypeInitialArrayPrototype(SloppyTNode<Context> context,
   1806                                                 SloppyTNode<Map> map);
   1807   TNode<BoolT> IsPrototypeTypedArrayPrototype(SloppyTNode<Context> context,
   1808                                               SloppyTNode<Map> map);
   1809   TNode<BoolT> IsSequentialStringInstanceType(
   1810       SloppyTNode<Int32T> instance_type);
   1811   TNode<BoolT> IsShortExternalStringInstanceType(
   1812       SloppyTNode<Int32T> instance_type);
   1813   TNode<BoolT> IsSpecialReceiverInstanceType(TNode<Int32T> instance_type);
   1814   TNode<BoolT> IsCustomElementsReceiverInstanceType(
   1815       TNode<Int32T> instance_type);
   1816   TNode<BoolT> IsSpecialReceiverMap(SloppyTNode<Map> map);
   1817   // Returns true if the map corresponds to non-special fast or dictionary
   1818   // object.
   1819   TNode<BoolT> IsSimpleObjectMap(TNode<Map> map);
   1820   TNode<BoolT> IsStringInstanceType(SloppyTNode<Int32T> instance_type);
   1821   TNode<BoolT> IsString(SloppyTNode<HeapObject> object);
   1822   TNode<BoolT> IsSymbolInstanceType(SloppyTNode<Int32T> instance_type);
   1823   TNode<BoolT> IsSymbol(SloppyTNode<HeapObject> object);
   1824   TNode<BoolT> IsUndetectableMap(SloppyTNode<Map> map);
   1825   TNode<BoolT> IsNotWeakFixedArraySubclass(SloppyTNode<HeapObject> object);
   1826   TNode<BoolT> IsZeroOrContext(SloppyTNode<Object> object);
   1827 
   1828   inline Node* IsSharedFunctionInfo(Node* object) {
   1829     return IsSharedFunctionInfoMap(LoadMap(object));
   1830   }
   1831 
   1832   TNode<BoolT> IsPromiseResolveProtectorCellInvalid();
   1833   TNode<BoolT> IsPromiseThenProtectorCellInvalid();
   1834   TNode<BoolT> IsArraySpeciesProtectorCellInvalid();
   1835   TNode<BoolT> IsTypedArraySpeciesProtectorCellInvalid();
   1836   TNode<BoolT> IsPromiseSpeciesProtectorCellInvalid();
   1837 
   1838   // True iff |object| is a Smi or a HeapNumber.
   1839   TNode<BoolT> IsNumber(SloppyTNode<Object> object);
   1840   // True iff |object| is a Smi or a HeapNumber or a BigInt.
   1841   TNode<BoolT> IsNumeric(SloppyTNode<Object> object);
   1842 
   1843   // True iff |number| is either a Smi, or a HeapNumber whose value is not
   1844   // within Smi range.
   1845   TNode<BoolT> IsNumberNormalized(SloppyTNode<Number> number);
   1846   TNode<BoolT> IsNumberPositive(SloppyTNode<Number> number);
   1847   TNode<BoolT> IsHeapNumberPositive(TNode<HeapNumber> number);
   1848 
   1849   // True iff {number} is non-negative and less or equal than 2**53-1.
   1850   TNode<BoolT> IsNumberNonNegativeSafeInteger(TNode<Number> number);
   1851 
   1852   // True iff {number} represents an integer value.
   1853   TNode<BoolT> IsInteger(TNode<Object> number);
   1854   TNode<BoolT> IsInteger(TNode<HeapNumber> number);
   1855 
   1856   // True iff abs({number}) <= 2**53 -1
   1857   TNode<BoolT> IsSafeInteger(TNode<Object> number);
   1858   TNode<BoolT> IsSafeInteger(TNode<HeapNumber> number);
   1859 
   1860   // True iff {number} represents a valid uint32t value.
   1861   TNode<BoolT> IsHeapNumberUint32(TNode<HeapNumber> number);
   1862 
   1863   // True iff {number} is a positive number and a valid array index in the range
   1864   // [0, 2^32-1).
   1865   TNode<BoolT> IsNumberArrayIndex(TNode<Number> number);
   1866 
   1867   Node* FixedArraySizeDoesntFitInNewSpace(
   1868       Node* element_count, int base_size = FixedArray::kHeaderSize,
   1869       ParameterMode mode = INTPTR_PARAMETERS);
   1870 
   1871   // ElementsKind helpers:
   1872   TNode<BoolT> ElementsKindEqual(TNode<Int32T> a, TNode<Int32T> b) {
   1873     return Word32Equal(a, b);
   1874   }
   1875   bool ElementsKindEqual(ElementsKind a, ElementsKind b) { return a == b; }
   1876   Node* IsFastElementsKind(Node* elements_kind);
   1877   bool IsFastElementsKind(ElementsKind kind) {
   1878     return v8::internal::IsFastElementsKind(kind);
   1879   }
   1880   TNode<BoolT> IsDictionaryElementsKind(TNode<Int32T> elements_kind) {
   1881     return ElementsKindEqual(elements_kind, Int32Constant(DICTIONARY_ELEMENTS));
   1882   }
   1883   TNode<BoolT> IsDoubleElementsKind(TNode<Int32T> elements_kind);
   1884   bool IsDoubleElementsKind(ElementsKind kind) {
   1885     return v8::internal::IsDoubleElementsKind(kind);
   1886   }
   1887   Node* IsFastSmiOrTaggedElementsKind(Node* elements_kind);
   1888   Node* IsFastSmiElementsKind(Node* elements_kind);
   1889   Node* IsHoleyFastElementsKind(Node* elements_kind);
   1890   Node* IsElementsKindGreaterThan(Node* target_kind,
   1891                                   ElementsKind reference_kind);
   1892 
   1893   // String helpers.
   1894   // Load a character from a String (might flatten a ConsString).
   1895   TNode<Int32T> StringCharCodeAt(SloppyTNode<String> string,
   1896                                  SloppyTNode<IntPtrT> index);
   1897   // Return the single character string with only {code}.
   1898   TNode<String> StringFromSingleCharCode(TNode<Int32T> code);
   1899 
   1900   // Return a new string object which holds a substring containing the range
   1901   // [from,to[ of string.
   1902   TNode<String> SubString(TNode<String> string, TNode<IntPtrT> from,
   1903                           TNode<IntPtrT> to);
   1904 
   1905   // Return a new string object produced by concatenating |first| with |second|.
   1906   TNode<String> StringAdd(Node* context, TNode<String> first,
   1907                           TNode<String> second, AllocationFlags flags = kNone);
   1908 
   1909   // Check if |string| is an indirect (thin or flat cons) string type that can
   1910   // be dereferenced by DerefIndirectString.
   1911   void BranchIfCanDerefIndirectString(Node* string, Node* instance_type,
   1912                                       Label* can_deref, Label* cannot_deref);
   1913   // Unpack an indirect (thin or flat cons) string type.
   1914   void DerefIndirectString(Variable* var_string, Node* instance_type);
   1915   // Check if |var_string| has an indirect (thin or flat cons) string type,
   1916   // and unpack it if so.
   1917   void MaybeDerefIndirectString(Variable* var_string, Node* instance_type,
   1918                                 Label* did_deref, Label* cannot_deref);
   1919   // Check if |var_left| or |var_right| has an indirect (thin or flat cons)
   1920   // string type, and unpack it/them if so. Fall through if nothing was done.
   1921   void MaybeDerefIndirectStrings(Variable* var_left, Node* left_instance_type,
   1922                                  Variable* var_right, Node* right_instance_type,
   1923                                  Label* did_something);
   1924   Node* DerefIndirectString(TNode<String> string, TNode<Int32T> instance_type,
   1925                             Label* cannot_deref);
   1926 
   1927   TNode<String> StringFromSingleCodePoint(TNode<Int32T> codepoint,
   1928                                           UnicodeEncoding encoding);
   1929 
   1930   // Type conversion helpers.
   1931   enum class BigIntHandling { kConvertToNumber, kThrow };
   1932   // Convert a String to a Number.
   1933   TNode<Number> StringToNumber(TNode<String> input);
   1934   // Convert a Number to a String.
   1935   TNode<String> NumberToString(TNode<Number> input);
   1936   // Convert an object to a name.
   1937   TNode<Name> ToName(SloppyTNode<Context> context, SloppyTNode<Object> value);
   1938   // Convert a Non-Number object to a Number.
   1939   TNode<Number> NonNumberToNumber(
   1940       SloppyTNode<Context> context, SloppyTNode<HeapObject> input,
   1941       BigIntHandling bigint_handling = BigIntHandling::kThrow);
   1942   // Convert a Non-Number object to a Numeric.
   1943   TNode<Numeric> NonNumberToNumeric(SloppyTNode<Context> context,
   1944                                     SloppyTNode<HeapObject> input);
   1945   // Convert any object to a Number.
   1946   // Conforms to ES#sec-tonumber if {bigint_handling} == kThrow.
   1947   // With {bigint_handling} == kConvertToNumber, matches behavior of
   1948   // tc39.github.io/proposal-bigint/#sec-number-constructor-number-value.
   1949   TNode<Number> ToNumber(
   1950       SloppyTNode<Context> context, SloppyTNode<Object> input,
   1951       BigIntHandling bigint_handling = BigIntHandling::kThrow);
   1952   TNode<Number> ToNumber_Inline(SloppyTNode<Context> context,
   1953                                 SloppyTNode<Object> input);
   1954 
   1955   // Try to convert an object to a BigInt. Throws on failure (e.g. for Numbers).
   1956   // https://tc39.github.io/proposal-bigint/#sec-to-bigint
   1957   TNode<BigInt> ToBigInt(SloppyTNode<Context> context,
   1958                          SloppyTNode<Object> input);
   1959 
   1960   // Converts |input| to one of 2^32 integer values in the range 0 through
   1961   // 2^32-1, inclusive.
   1962   // ES#sec-touint32
   1963   TNode<Number> ToUint32(SloppyTNode<Context> context,
   1964                          SloppyTNode<Object> input);
   1965 
   1966   // Convert any object to a String.
   1967   TNode<String> ToString(SloppyTNode<Context> context,
   1968                          SloppyTNode<Object> input);
   1969   TNode<String> ToString_Inline(SloppyTNode<Context> context,
   1970                                 SloppyTNode<Object> input);
   1971 
   1972   // Convert any object to a Primitive.
   1973   Node* JSReceiverToPrimitive(Node* context, Node* input);
   1974 
   1975   TNode<JSReceiver> ToObject(SloppyTNode<Context> context,
   1976                              SloppyTNode<Object> input);
   1977 
   1978   // Same as ToObject but avoids the Builtin call if |input| is already a
   1979   // JSReceiver.
   1980   TNode<JSReceiver> ToObject_Inline(TNode<Context> context,
   1981                                     TNode<Object> input);
   1982 
   1983   enum ToIntegerTruncationMode {
   1984     kNoTruncation,
   1985     kTruncateMinusZero,
   1986   };
   1987 
   1988   // ES6 7.1.17 ToIndex, but jumps to range_error if the result is not a Smi.
   1989   TNode<Smi> ToSmiIndex(TNode<Object> input, TNode<Context> context,
   1990                         Label* range_error);
   1991 
   1992   // ES6 7.1.15 ToLength, but jumps to range_error if the result is not a Smi.
   1993   TNode<Smi> ToSmiLength(TNode<Object> input, TNode<Context> context,
   1994                          Label* range_error);
   1995 
   1996   // ES6 7.1.15 ToLength, but with inlined fast path.
   1997   TNode<Number> ToLength_Inline(SloppyTNode<Context> context,
   1998                                 SloppyTNode<Object> input);
   1999 
   2000   // ES6 7.1.4 ToInteger ( argument )
   2001   TNode<Number> ToInteger_Inline(SloppyTNode<Context> context,
   2002                                  SloppyTNode<Object> input,
   2003                                  ToIntegerTruncationMode mode = kNoTruncation);
   2004   TNode<Number> ToInteger(SloppyTNode<Context> context,
   2005                           SloppyTNode<Object> input,
   2006                           ToIntegerTruncationMode mode = kNoTruncation);
   2007 
   2008   // Returns a node that contains a decoded (unsigned!) value of a bit
   2009   // field |BitField| in |word32|. Returns result as an uint32 node.
   2010   template <typename BitField>
   2011   TNode<Uint32T> DecodeWord32(SloppyTNode<Word32T> word32) {
   2012     return DecodeWord32(word32, BitField::kShift, BitField::kMask);
   2013   }
   2014 
   2015   // Returns a node that contains a decoded (unsigned!) value of a bit
   2016   // field |BitField| in |word|. Returns result as a word-size node.
   2017   template <typename BitField>
   2018   TNode<UintPtrT> DecodeWord(SloppyTNode<WordT> word) {
   2019     return DecodeWord(word, BitField::kShift, BitField::kMask);
   2020   }
   2021 
   2022   // Returns a node that contains a decoded (unsigned!) value of a bit
   2023   // field |BitField| in |word32|. Returns result as a word-size node.
   2024   template <typename BitField>
   2025   TNode<UintPtrT> DecodeWordFromWord32(SloppyTNode<Word32T> word32) {
   2026     return DecodeWord<BitField>(ChangeUint32ToWord(word32));
   2027   }
   2028 
   2029   // Returns a node that contains a decoded (unsigned!) value of a bit
   2030   // field |BitField| in |word|. Returns result as an uint32 node.
   2031   template <typename BitField>
   2032   TNode<Uint32T> DecodeWord32FromWord(SloppyTNode<WordT> word) {
   2033     return UncheckedCast<Uint32T>(
   2034         TruncateIntPtrToInt32(Signed(DecodeWord<BitField>(word))));
   2035   }
   2036 
   2037   // Decodes an unsigned (!) value from |word32| to an uint32 node.
   2038   TNode<Uint32T> DecodeWord32(SloppyTNode<Word32T> word32, uint32_t shift,
   2039                               uint32_t mask);
   2040 
   2041   // Decodes an unsigned (!) value from |word| to a word-size node.
   2042   TNode<UintPtrT> DecodeWord(SloppyTNode<WordT> word, uint32_t shift,
   2043                              uint32_t mask);
   2044 
   2045   // Returns a node that contains the updated values of a |BitField|.
   2046   template <typename BitField>
   2047   TNode<WordT> UpdateWord(TNode<WordT> word, TNode<WordT> value) {
   2048     return UpdateWord(word, value, BitField::kShift, BitField::kMask);
   2049   }
   2050 
   2051   // Returns a node that contains the updated {value} inside {word} starting
   2052   // at {shift} and fitting in {mask}.
   2053   TNode<WordT> UpdateWord(TNode<WordT> word, TNode<WordT> value, uint32_t shift,
   2054                           uint32_t mask);
   2055 
   2056   // Returns true if any of the |T|'s bits in given |word32| are set.
   2057   template <typename T>
   2058   TNode<BoolT> IsSetWord32(SloppyTNode<Word32T> word32) {
   2059     return IsSetWord32(word32, T::kMask);
   2060   }
   2061 
   2062   // Returns true if any of the mask's bits in given |word32| are set.
   2063   TNode<BoolT> IsSetWord32(SloppyTNode<Word32T> word32, uint32_t mask) {
   2064     return Word32NotEqual(Word32And(word32, Int32Constant(mask)),
   2065                           Int32Constant(0));
   2066   }
   2067 
   2068   // Returns true if none of the mask's bits in given |word32| are set.
   2069   TNode<BoolT> IsNotSetWord32(SloppyTNode<Word32T> word32, uint32_t mask) {
   2070     return Word32Equal(Word32And(word32, Int32Constant(mask)),
   2071                        Int32Constant(0));
   2072   }
   2073 
   2074   // Returns true if all of the mask's bits in a given |word32| are set.
   2075   TNode<BoolT> IsAllSetWord32(SloppyTNode<Word32T> word32, uint32_t mask) {
   2076     TNode<Int32T> const_mask = Int32Constant(mask);
   2077     return Word32Equal(Word32And(word32, const_mask), const_mask);
   2078   }
   2079 
   2080   // Returns true if any of the |T|'s bits in given |word| are set.
   2081   template <typename T>
   2082   TNode<BoolT> IsSetWord(SloppyTNode<WordT> word) {
   2083     return IsSetWord(word, T::kMask);
   2084   }
   2085 
   2086   // Returns true if any of the mask's bits in given |word| are set.
   2087   TNode<BoolT> IsSetWord(SloppyTNode<WordT> word, uint32_t mask) {
   2088     return WordNotEqual(WordAnd(word, IntPtrConstant(mask)), IntPtrConstant(0));
   2089   }
   2090 
   2091   // Returns true if any of the mask's bit are set in the given Smi.
   2092   // Smi-encoding of the mask is performed implicitly!
   2093   TNode<BoolT> IsSetSmi(SloppyTNode<Smi> smi, int untagged_mask) {
   2094     intptr_t mask_word = bit_cast<intptr_t>(Smi::FromInt(untagged_mask));
   2095     return WordNotEqual(
   2096         WordAnd(BitcastTaggedToWord(smi), IntPtrConstant(mask_word)),
   2097         IntPtrConstant(0));
   2098   }
   2099 
   2100   // Returns true if all of the |T|'s bits in given |word32| are clear.
   2101   template <typename T>
   2102   TNode<BoolT> IsClearWord32(SloppyTNode<Word32T> word32) {
   2103     return IsClearWord32(word32, T::kMask);
   2104   }
   2105 
   2106   // Returns true if all of the mask's bits in given |word32| are clear.
   2107   TNode<BoolT> IsClearWord32(SloppyTNode<Word32T> word32, uint32_t mask) {
   2108     return Word32Equal(Word32And(word32, Int32Constant(mask)),
   2109                        Int32Constant(0));
   2110   }
   2111 
   2112   // Returns true if all of the |T|'s bits in given |word| are clear.
   2113   template <typename T>
   2114   TNode<BoolT> IsClearWord(SloppyTNode<WordT> word) {
   2115     return IsClearWord(word, T::kMask);
   2116   }
   2117 
   2118   // Returns true if all of the mask's bits in given |word| are clear.
   2119   TNode<BoolT> IsClearWord(SloppyTNode<WordT> word, uint32_t mask) {
   2120     return WordEqual(WordAnd(word, IntPtrConstant(mask)), IntPtrConstant(0));
   2121   }
   2122 
   2123   void SetCounter(StatsCounter* counter, int value);
   2124   void IncrementCounter(StatsCounter* counter, int delta);
   2125   void DecrementCounter(StatsCounter* counter, int delta);
   2126 
   2127   void Increment(Variable* variable, int value = 1,
   2128                  ParameterMode mode = INTPTR_PARAMETERS);
   2129   void Decrement(Variable* variable, int value = 1,
   2130                  ParameterMode mode = INTPTR_PARAMETERS) {
   2131     Increment(variable, -value, mode);
   2132   }
   2133 
   2134   // Generates "if (false) goto label" code. Useful for marking a label as
   2135   // "live" to avoid assertion failures during graph building. In the resulting
   2136   // code this check will be eliminated.
   2137   void Use(Label* label);
   2138 
   2139   // Various building blocks for stubs doing property lookups.
   2140 
   2141   // |if_notinternalized| is optional; |if_bailout| will be used by default.
   2142   void TryToName(Node* key, Label* if_keyisindex, Variable* var_index,
   2143                  Label* if_keyisunique, Variable* var_unique, Label* if_bailout,
   2144                  Label* if_notinternalized = nullptr);
   2145 
   2146   // Performs a hash computation and string table lookup for the given string,
   2147   // and jumps to:
   2148   // - |if_index| if the string is an array index like "123"; |var_index|
   2149   //              will contain the intptr representation of that index.
   2150   // - |if_internalized| if the string exists in the string table; the
   2151   //                     internalized version will be in |var_internalized|.
   2152   // - |if_not_internalized| if the string is not in the string table (but
   2153   //                         does not add it).
   2154   // - |if_bailout| for unsupported cases (e.g. uncachable array index).
   2155   void TryInternalizeString(Node* string, Label* if_index, Variable* var_index,
   2156                             Label* if_internalized, Variable* var_internalized,
   2157                             Label* if_not_internalized, Label* if_bailout);
   2158 
   2159   // Calculates array index for given dictionary entry and entry field.
   2160   // See Dictionary::EntryToIndex().
   2161   template <typename Dictionary>
   2162   TNode<IntPtrT> EntryToIndex(TNode<IntPtrT> entry, int field_index);
   2163   template <typename Dictionary>
   2164   TNode<IntPtrT> EntryToIndex(TNode<IntPtrT> entry) {
   2165     return EntryToIndex<Dictionary>(entry, Dictionary::kEntryKeyIndex);
   2166   }
   2167 
   2168   // Loads the details for the entry with the given key_index.
   2169   // Returns an untagged int32.
   2170   template <class ContainerType>
   2171   TNode<Uint32T> LoadDetailsByKeyIndex(Node* container, Node* key_index) {
   2172     static_assert(!std::is_same<ContainerType, DescriptorArray>::value,
   2173                   "Use the non-templatized version for DescriptorArray");
   2174     const int kKeyToDetailsOffset =
   2175         (ContainerType::kEntryDetailsIndex - ContainerType::kEntryKeyIndex) *
   2176         kPointerSize;
   2177     return Unsigned(LoadAndUntagToWord32FixedArrayElement(
   2178         CAST(container), key_index, kKeyToDetailsOffset));
   2179   }
   2180 
   2181   // Loads the value for the entry with the given key_index.
   2182   // Returns a tagged value.
   2183   template <class ContainerType>
   2184   TNode<Object> LoadValueByKeyIndex(Node* container, Node* key_index) {
   2185     static_assert(!std::is_same<ContainerType, DescriptorArray>::value,
   2186                   "Use the non-templatized version for DescriptorArray");
   2187     const int kKeyToValueOffset =
   2188         (ContainerType::kEntryValueIndex - ContainerType::kEntryKeyIndex) *
   2189         kPointerSize;
   2190     return LoadFixedArrayElement(CAST(container), key_index, kKeyToValueOffset);
   2191   }
   2192 
   2193   TNode<Uint32T> LoadDetailsByKeyIndex(TNode<DescriptorArray> container,
   2194                                        TNode<IntPtrT> key_index);
   2195   TNode<Object> LoadValueByKeyIndex(TNode<DescriptorArray> container,
   2196                                     TNode<IntPtrT> key_index);
   2197   TNode<MaybeObject> LoadFieldTypeByKeyIndex(TNode<DescriptorArray> container,
   2198                                              TNode<IntPtrT> key_index);
   2199 
   2200   // Stores the details for the entry with the given key_index.
   2201   // |details| must be a Smi.
   2202   template <class ContainerType>
   2203   void StoreDetailsByKeyIndex(TNode<ContainerType> container,
   2204                               TNode<IntPtrT> key_index, TNode<Smi> details) {
   2205     const int kKeyToDetailsOffset =
   2206         (ContainerType::kEntryDetailsIndex - ContainerType::kEntryKeyIndex) *
   2207         kPointerSize;
   2208     StoreFixedArrayElement(container, key_index, details, SKIP_WRITE_BARRIER,
   2209                            kKeyToDetailsOffset);
   2210   }
   2211 
   2212   // Stores the value for the entry with the given key_index.
   2213   template <class ContainerType>
   2214   void StoreValueByKeyIndex(
   2215       TNode<ContainerType> container, TNode<IntPtrT> key_index,
   2216       TNode<Object> value,
   2217       WriteBarrierMode write_barrier = UPDATE_WRITE_BARRIER) {
   2218     const int kKeyToValueOffset =
   2219         (ContainerType::kEntryValueIndex - ContainerType::kEntryKeyIndex) *
   2220         kPointerSize;
   2221     StoreFixedArrayElement(container, key_index, value, write_barrier,
   2222                            kKeyToValueOffset);
   2223   }
   2224 
   2225   // Calculate a valid size for the a hash table.
   2226   TNode<IntPtrT> HashTableComputeCapacity(TNode<IntPtrT> at_least_space_for);
   2227 
   2228   template <class Dictionary>
   2229   TNode<Smi> GetNumberOfElements(TNode<Dictionary> dictionary) {
   2230     return CAST(
   2231         LoadFixedArrayElement(dictionary, Dictionary::kNumberOfElementsIndex));
   2232   }
   2233 
   2234   template <class Dictionary>
   2235   void SetNumberOfElements(TNode<Dictionary> dictionary,
   2236                            TNode<Smi> num_elements_smi) {
   2237     StoreFixedArrayElement(dictionary, Dictionary::kNumberOfElementsIndex,
   2238                            num_elements_smi, SKIP_WRITE_BARRIER);
   2239   }
   2240 
   2241   template <class Dictionary>
   2242   TNode<Smi> GetNumberOfDeletedElements(TNode<Dictionary> dictionary) {
   2243     return CAST(LoadFixedArrayElement(
   2244         dictionary, Dictionary::kNumberOfDeletedElementsIndex));
   2245   }
   2246 
   2247   template <class Dictionary>
   2248   void SetNumberOfDeletedElements(TNode<Dictionary> dictionary,
   2249                                   TNode<Smi> num_deleted_smi) {
   2250     StoreFixedArrayElement(dictionary,
   2251                            Dictionary::kNumberOfDeletedElementsIndex,
   2252                            num_deleted_smi, SKIP_WRITE_BARRIER);
   2253   }
   2254 
   2255   template <class Dictionary>
   2256   TNode<Smi> GetCapacity(TNode<Dictionary> dictionary) {
   2257     return CAST(LoadFixedArrayElement(dictionary, Dictionary::kCapacityIndex));
   2258   }
   2259 
   2260   template <class Dictionary>
   2261   TNode<Smi> GetNextEnumerationIndex(TNode<Dictionary> dictionary) {
   2262     return CAST(LoadFixedArrayElement(dictionary,
   2263                                       Dictionary::kNextEnumerationIndexIndex));
   2264   }
   2265 
   2266   template <class Dictionary>
   2267   void SetNextEnumerationIndex(TNode<Dictionary> dictionary,
   2268                                TNode<Smi> next_enum_index_smi) {
   2269     StoreFixedArrayElement(dictionary, Dictionary::kNextEnumerationIndexIndex,
   2270                            next_enum_index_smi, SKIP_WRITE_BARRIER);
   2271   }
   2272 
   2273   // Looks up an entry in a NameDictionaryBase successor. If the entry is found
   2274   // control goes to {if_found} and {var_name_index} contains an index of the
   2275   // key field of the entry found. If the key is not found control goes to
   2276   // {if_not_found}.
   2277   static const int kInlinedDictionaryProbes = 4;
   2278   enum LookupMode { kFindExisting, kFindInsertionIndex };
   2279 
   2280   template <typename Dictionary>
   2281   TNode<HeapObject> LoadName(TNode<HeapObject> key);
   2282 
   2283   template <typename Dictionary>
   2284   void NameDictionaryLookup(TNode<Dictionary> dictionary,
   2285                             TNode<Name> unique_name, Label* if_found,
   2286                             TVariable<IntPtrT>* var_name_index,
   2287                             Label* if_not_found,
   2288                             int inlined_probes = kInlinedDictionaryProbes,
   2289                             LookupMode mode = kFindExisting);
   2290 
   2291   Node* ComputeIntegerHash(Node* key);
   2292   Node* ComputeIntegerHash(Node* key, Node* seed);
   2293 
   2294   void NumberDictionaryLookup(TNode<NumberDictionary> dictionary,
   2295                               TNode<IntPtrT> intptr_index, Label* if_found,
   2296                               TVariable<IntPtrT>* var_entry,
   2297                               Label* if_not_found);
   2298 
   2299   TNode<Object> BasicLoadNumberDictionaryElement(
   2300       TNode<NumberDictionary> dictionary, TNode<IntPtrT> intptr_index,
   2301       Label* not_data, Label* if_hole);
   2302   void BasicStoreNumberDictionaryElement(TNode<NumberDictionary> dictionary,
   2303                                          TNode<IntPtrT> intptr_index,
   2304                                          TNode<Object> value, Label* not_data,
   2305                                          Label* if_hole, Label* read_only);
   2306 
   2307   template <class Dictionary>
   2308   void FindInsertionEntry(TNode<Dictionary> dictionary, TNode<Name> key,
   2309                           TVariable<IntPtrT>* var_key_index);
   2310 
   2311   template <class Dictionary>
   2312   void InsertEntry(TNode<Dictionary> dictionary, TNode<Name> key,
   2313                    TNode<Object> value, TNode<IntPtrT> index,
   2314                    TNode<Smi> enum_index);
   2315 
   2316   template <class Dictionary>
   2317   void Add(TNode<Dictionary> dictionary, TNode<Name> key, TNode<Object> value,
   2318            Label* bailout);
   2319 
   2320   // Tries to check if {object} has own {unique_name} property.
   2321   void TryHasOwnProperty(Node* object, Node* map, Node* instance_type,
   2322                          Node* unique_name, Label* if_found,
   2323                          Label* if_not_found, Label* if_bailout);
   2324 
   2325   // Operating mode for TryGetOwnProperty and CallGetterIfAccessor
   2326   // kReturnAccessorPair is used when we're only getting the property descriptor
   2327   enum GetOwnPropertyMode { kCallJSGetter, kReturnAccessorPair };
   2328   // Tries to get {object}'s own {unique_name} property value. If the property
   2329   // is an accessor then it also calls a getter. If the property is a double
   2330   // field it re-wraps value in an immutable heap number.
   2331   void TryGetOwnProperty(Node* context, Node* receiver, Node* object, Node* map,
   2332                          Node* instance_type, Node* unique_name,
   2333                          Label* if_found, Variable* var_value,
   2334                          Label* if_not_found, Label* if_bailout);
   2335   void TryGetOwnProperty(Node* context, Node* receiver, Node* object, Node* map,
   2336                          Node* instance_type, Node* unique_name,
   2337                          Label* if_found, Variable* var_value,
   2338                          Variable* var_details, Variable* var_raw_value,
   2339                          Label* if_not_found, Label* if_bailout,
   2340                          GetOwnPropertyMode mode);
   2341 
   2342   TNode<Object> GetProperty(SloppyTNode<Context> context,
   2343                             SloppyTNode<Object> receiver, Handle<Name> name) {
   2344     return GetProperty(context, receiver, HeapConstant(name));
   2345   }
   2346 
   2347   TNode<Object> GetProperty(SloppyTNode<Context> context,
   2348                             SloppyTNode<Object> receiver,
   2349                             SloppyTNode<Object> name) {
   2350     return CallBuiltin(Builtins::kGetProperty, context, receiver, name);
   2351   }
   2352 
   2353   TNode<Object> SetPropertyStrict(TNode<Context> context,
   2354                                   TNode<Object> receiver, TNode<Object> key,
   2355                                   TNode<Object> value) {
   2356     return CallBuiltin(Builtins::kSetProperty, context, receiver, key, value);
   2357   }
   2358 
   2359   Node* GetMethod(Node* context, Node* object, Handle<Name> name,
   2360                   Label* if_null_or_undefined);
   2361 
   2362   template <class... TArgs>
   2363   TNode<Object> CallBuiltin(Builtins::Name id, SloppyTNode<Object> context,
   2364                             TArgs... args) {
   2365     DCHECK_IMPLIES(Builtins::KindOf(id) == Builtins::TFJ,
   2366                    !Builtins::IsLazy(id));
   2367     return CallStub<Object>(Builtins::CallableFor(isolate(), id), context,
   2368                             args...);
   2369   }
   2370 
   2371   template <class... TArgs>
   2372   void TailCallBuiltin(Builtins::Name id, SloppyTNode<Object> context,
   2373                        TArgs... args) {
   2374     DCHECK_IMPLIES(Builtins::KindOf(id) == Builtins::TFJ,
   2375                    !Builtins::IsLazy(id));
   2376     return TailCallStub(Builtins::CallableFor(isolate(), id), context, args...);
   2377   }
   2378 
   2379   void LoadPropertyFromFastObject(Node* object, Node* map,
   2380                                   TNode<DescriptorArray> descriptors,
   2381                                   Node* name_index, Variable* var_details,
   2382                                   Variable* var_value);
   2383 
   2384   void LoadPropertyFromFastObject(Node* object, Node* map,
   2385                                   TNode<DescriptorArray> descriptors,
   2386                                   Node* name_index, Node* details,
   2387                                   Variable* var_value);
   2388 
   2389   void LoadPropertyFromNameDictionary(Node* dictionary, Node* entry,
   2390                                       Variable* var_details,
   2391                                       Variable* var_value);
   2392 
   2393   void LoadPropertyFromGlobalDictionary(Node* dictionary, Node* entry,
   2394                                         Variable* var_details,
   2395                                         Variable* var_value, Label* if_deleted);
   2396 
   2397   // Generic property lookup generator. If the {object} is fast and
   2398   // {unique_name} property is found then the control goes to {if_found_fast}
   2399   // label and {var_meta_storage} and {var_name_index} will contain
   2400   // DescriptorArray and an index of the descriptor's name respectively.
   2401   // If the {object} is slow or global then the control goes to {if_found_dict}
   2402   // or {if_found_global} and the {var_meta_storage} and {var_name_index} will
   2403   // contain a dictionary and an index of the key field of the found entry.
   2404   // If property is not found or given lookup is not supported then
   2405   // the control goes to {if_not_found} or {if_bailout} respectively.
   2406   //
   2407   // Note: this code does not check if the global dictionary points to deleted
   2408   // entry! This has to be done by the caller.
   2409   void TryLookupProperty(SloppyTNode<JSObject> object, SloppyTNode<Map> map,
   2410                          SloppyTNode<Int32T> instance_type,
   2411                          SloppyTNode<Name> unique_name, Label* if_found_fast,
   2412                          Label* if_found_dict, Label* if_found_global,
   2413                          TVariable<HeapObject>* var_meta_storage,
   2414                          TVariable<IntPtrT>* var_name_index,
   2415                          Label* if_not_found, Label* if_bailout);
   2416 
   2417   // This is a building block for TryLookupProperty() above. Supports only
   2418   // non-special fast and dictionary objects.
   2419   void TryLookupPropertyInSimpleObject(TNode<JSObject> object, TNode<Map> map,
   2420                                        TNode<Name> unique_name,
   2421                                        Label* if_found_fast,
   2422                                        Label* if_found_dict,
   2423                                        TVariable<HeapObject>* var_meta_storage,
   2424                                        TVariable<IntPtrT>* var_name_index,
   2425                                        Label* if_not_found);
   2426 
   2427   // This method jumps to if_found if the element is known to exist. To
   2428   // if_absent if it's known to not exist. To if_not_found if the prototype
   2429   // chain needs to be checked. And if_bailout if the lookup is unsupported.
   2430   void TryLookupElement(Node* object, Node* map,
   2431                         SloppyTNode<Int32T> instance_type,
   2432                         SloppyTNode<IntPtrT> intptr_index, Label* if_found,
   2433                         Label* if_absent, Label* if_not_found,
   2434                         Label* if_bailout);
   2435 
   2436   // This is a type of a lookup in holder generator function. In case of a
   2437   // property lookup the {key} is guaranteed to be an unique name and in case of
   2438   // element lookup the key is an Int32 index.
   2439   typedef std::function<void(Node* receiver, Node* holder, Node* map,
   2440                              Node* instance_type, Node* key, Label* next_holder,
   2441                              Label* if_bailout)>
   2442       LookupInHolder;
   2443 
   2444   // For integer indexed exotic cases, check if the given string cannot be a
   2445   // special index. If we are not sure that the given string is not a special
   2446   // index with a simple check, return False. Note that "False" return value
   2447   // does not mean that the name_string is a special index in the current
   2448   // implementation.
   2449   void BranchIfMaybeSpecialIndex(TNode<String> name_string,
   2450                                  Label* if_maybe_special_index,
   2451                                  Label* if_not_special_index);
   2452 
   2453   // Generic property prototype chain lookup generator.
   2454   // For properties it generates lookup using given {lookup_property_in_holder}
   2455   // and for elements it uses {lookup_element_in_holder}.
   2456   // Upon reaching the end of prototype chain the control goes to {if_end}.
   2457   // If it can't handle the case {receiver}/{key} case then the control goes
   2458   // to {if_bailout}.
   2459   // If {if_proxy} is nullptr, proxies go to if_bailout.
   2460   void TryPrototypeChainLookup(Node* receiver, Node* key,
   2461                                const LookupInHolder& lookup_property_in_holder,
   2462                                const LookupInHolder& lookup_element_in_holder,
   2463                                Label* if_end, Label* if_bailout,
   2464                                Label* if_proxy = nullptr);
   2465 
   2466   // Instanceof helpers.
   2467   // Returns true if {object} has {prototype} somewhere in it's prototype
   2468   // chain, otherwise false is returned. Might cause arbitrary side effects
   2469   // due to [[GetPrototypeOf]] invocations.
   2470   Node* HasInPrototypeChain(Node* context, Node* object, Node* prototype);
   2471   // ES6 section 7.3.19 OrdinaryHasInstance (C, O)
   2472   Node* OrdinaryHasInstance(Node* context, Node* callable, Node* object);
   2473 
   2474   // Load type feedback vector from the stub caller's frame.
   2475   TNode<FeedbackVector> LoadFeedbackVectorForStub();
   2476 
   2477   // Load type feedback vector for the given closure.
   2478   TNode<FeedbackVector> LoadFeedbackVector(SloppyTNode<JSFunction> closure,
   2479                                            Label* if_undefined = nullptr);
   2480 
   2481   // Update the type feedback vector.
   2482   void UpdateFeedback(Node* feedback, Node* feedback_vector, Node* slot_id);
   2483 
   2484   // Report that there was a feedback update, performing any tasks that should
   2485   // be done after a feedback update.
   2486   void ReportFeedbackUpdate(SloppyTNode<FeedbackVector> feedback_vector,
   2487                             SloppyTNode<IntPtrT> slot_id, const char* reason);
   2488 
   2489   // Combine the new feedback with the existing_feedback. Do nothing if
   2490   // existing_feedback is nullptr.
   2491   void CombineFeedback(Variable* existing_feedback, int feedback);
   2492   void CombineFeedback(Variable* existing_feedback, Node* feedback);
   2493 
   2494   // Overwrite the existing feedback with new_feedback. Do nothing if
   2495   // existing_feedback is nullptr.
   2496   void OverwriteFeedback(Variable* existing_feedback, int new_feedback);
   2497 
   2498   // Check if a property name might require protector invalidation when it is
   2499   // used for a property store or deletion.
   2500   void CheckForAssociatedProtector(Node* name, Label* if_protector);
   2501 
   2502   TNode<Map> LoadReceiverMap(SloppyTNode<Object> receiver);
   2503 
   2504   // Emits keyed sloppy arguments load. Returns either the loaded value.
   2505   Node* LoadKeyedSloppyArguments(Node* receiver, Node* key, Label* bailout) {
   2506     return EmitKeyedSloppyArguments(receiver, key, nullptr, bailout);
   2507   }
   2508 
   2509   // Emits keyed sloppy arguments store.
   2510   void StoreKeyedSloppyArguments(Node* receiver, Node* key, Node* value,
   2511                                  Label* bailout) {
   2512     DCHECK_NOT_NULL(value);
   2513     EmitKeyedSloppyArguments(receiver, key, value, bailout);
   2514   }
   2515 
   2516   // Loads script context from the script context table.
   2517   TNode<Context> LoadScriptContext(TNode<Context> context,
   2518                                    TNode<IntPtrT> context_index);
   2519 
   2520   Node* Int32ToUint8Clamped(Node* int32_value);
   2521   Node* Float64ToUint8Clamped(Node* float64_value);
   2522 
   2523   Node* PrepareValueForWriteToTypedArray(TNode<Object> input,
   2524                                          ElementsKind elements_kind,
   2525                                          TNode<Context> context);
   2526 
   2527   // Store value to an elements array with given elements kind.
   2528   void StoreElement(Node* elements, ElementsKind kind, Node* index, Node* value,
   2529                     ParameterMode mode);
   2530 
   2531   void EmitBigTypedArrayElementStore(TNode<JSTypedArray> object,
   2532                                      TNode<FixedTypedArrayBase> elements,
   2533                                      TNode<IntPtrT> intptr_key,
   2534                                      TNode<Object> value,
   2535                                      TNode<Context> context,
   2536                                      Label* opt_if_neutered);
   2537   // Part of the above, refactored out to reuse in another place
   2538   void EmitBigTypedArrayElementStore(TNode<FixedTypedArrayBase> elements,
   2539                                      TNode<RawPtrT> backing_store,
   2540                                      TNode<IntPtrT> offset,
   2541                                      TNode<BigInt> bigint_value);
   2542 
   2543   void EmitElementStore(Node* object, Node* key, Node* value, bool is_jsarray,
   2544                         ElementsKind elements_kind,
   2545                         KeyedAccessStoreMode store_mode, Label* bailout,
   2546                         Node* context);
   2547 
   2548   Node* CheckForCapacityGrow(Node* object, Node* elements, ElementsKind kind,
   2549                              KeyedAccessStoreMode store_mode, Node* length,
   2550                              Node* key, ParameterMode mode, bool is_js_array,
   2551                              Label* bailout);
   2552 
   2553   Node* CopyElementsOnWrite(Node* object, Node* elements, ElementsKind kind,
   2554                             Node* length, ParameterMode mode, Label* bailout);
   2555 
   2556   void TransitionElementsKind(Node* object, Node* map, ElementsKind from_kind,
   2557                               ElementsKind to_kind, bool is_jsarray,
   2558                               Label* bailout);
   2559 
   2560   void TrapAllocationMemento(Node* object, Label* memento_found);
   2561 
   2562   TNode<IntPtrT> PageFromAddress(TNode<IntPtrT> address);
   2563 
   2564   // Store a weak in-place reference into the FeedbackVector.
   2565   TNode<MaybeObject> StoreWeakReferenceInFeedbackVector(
   2566       SloppyTNode<FeedbackVector> feedback_vector, Node* slot,
   2567       SloppyTNode<HeapObject> value, int additional_offset = 0,
   2568       ParameterMode parameter_mode = INTPTR_PARAMETERS);
   2569 
   2570   // Create a new AllocationSite and install it into a feedback vector.
   2571   TNode<AllocationSite> CreateAllocationSiteInFeedbackVector(
   2572       SloppyTNode<FeedbackVector> feedback_vector, TNode<Smi> slot);
   2573 
   2574   // TODO(ishell, cbruni): Change to HasBoilerplate.
   2575   TNode<BoolT> NotHasBoilerplate(TNode<Object> maybe_literal_site);
   2576   TNode<Smi> LoadTransitionInfo(TNode<AllocationSite> allocation_site);
   2577   TNode<JSObject> LoadBoilerplate(TNode<AllocationSite> allocation_site);
   2578   TNode<Int32T> LoadElementsKind(TNode<AllocationSite> allocation_site);
   2579 
   2580   enum class IndexAdvanceMode { kPre, kPost };
   2581 
   2582   typedef std::function<void(Node* index)> FastLoopBody;
   2583 
   2584   Node* BuildFastLoop(const VariableList& var_list, Node* start_index,
   2585                       Node* end_index, const FastLoopBody& body, int increment,
   2586                       ParameterMode parameter_mode,
   2587                       IndexAdvanceMode advance_mode = IndexAdvanceMode::kPre);
   2588 
   2589   Node* BuildFastLoop(Node* start_index, Node* end_index,
   2590                       const FastLoopBody& body, int increment,
   2591                       ParameterMode parameter_mode,
   2592                       IndexAdvanceMode advance_mode = IndexAdvanceMode::kPre) {
   2593     return BuildFastLoop(VariableList(0, zone()), start_index, end_index, body,
   2594                          increment, parameter_mode, advance_mode);
   2595   }
   2596 
   2597   enum class ForEachDirection { kForward, kReverse };
   2598 
   2599   typedef std::function<void(Node* fixed_array, Node* offset)>
   2600       FastFixedArrayForEachBody;
   2601 
   2602   void BuildFastFixedArrayForEach(
   2603       const CodeStubAssembler::VariableList& vars, Node* fixed_array,
   2604       ElementsKind kind, Node* first_element_inclusive,
   2605       Node* last_element_exclusive, const FastFixedArrayForEachBody& body,
   2606       ParameterMode mode = INTPTR_PARAMETERS,
   2607       ForEachDirection direction = ForEachDirection::kReverse);
   2608 
   2609   void BuildFastFixedArrayForEach(
   2610       Node* fixed_array, ElementsKind kind, Node* first_element_inclusive,
   2611       Node* last_element_exclusive, const FastFixedArrayForEachBody& body,
   2612       ParameterMode mode = INTPTR_PARAMETERS,
   2613       ForEachDirection direction = ForEachDirection::kReverse) {
   2614     CodeStubAssembler::VariableList list(0, zone());
   2615     BuildFastFixedArrayForEach(list, fixed_array, kind, first_element_inclusive,
   2616                                last_element_exclusive, body, mode, direction);
   2617   }
   2618 
   2619   TNode<IntPtrT> GetArrayAllocationSize(Node* element_count, ElementsKind kind,
   2620                                         ParameterMode mode, int header_size) {
   2621     return ElementOffsetFromIndex(element_count, kind, mode, header_size);
   2622   }
   2623 
   2624   TNode<IntPtrT> GetFixedArrayAllocationSize(Node* element_count,
   2625                                              ElementsKind kind,
   2626                                              ParameterMode mode) {
   2627     return GetArrayAllocationSize(element_count, kind, mode,
   2628                                   FixedArray::kHeaderSize);
   2629   }
   2630 
   2631   TNode<IntPtrT> GetPropertyArrayAllocationSize(Node* element_count,
   2632                                                 ParameterMode mode) {
   2633     return GetArrayAllocationSize(element_count, PACKED_ELEMENTS, mode,
   2634                                   PropertyArray::kHeaderSize);
   2635   }
   2636 
   2637   void GotoIfFixedArraySizeDoesntFitInNewSpace(Node* element_count,
   2638                                                Label* doesnt_fit, int base_size,
   2639                                                ParameterMode mode);
   2640 
   2641   void InitializeFieldsWithRoot(Node* object, Node* start_offset,
   2642                                 Node* end_offset, Heap::RootListIndex root);
   2643 
   2644   Node* RelationalComparison(Operation op, Node* left, Node* right,
   2645                              Node* context,
   2646                              Variable* var_type_feedback = nullptr);
   2647 
   2648   void BranchIfNumberRelationalComparison(Operation op, Node* left, Node* right,
   2649                                           Label* if_true, Label* if_false);
   2650 
   2651   void BranchIfNumberLessThan(Node* left, Node* right, Label* if_true,
   2652                               Label* if_false) {
   2653     BranchIfNumberRelationalComparison(Operation::kLessThan, left, right,
   2654                                        if_true, if_false);
   2655   }
   2656 
   2657   void BranchIfNumberLessThanOrEqual(Node* left, Node* right, Label* if_true,
   2658                                      Label* if_false) {
   2659     BranchIfNumberRelationalComparison(Operation::kLessThanOrEqual, left, right,
   2660                                        if_true, if_false);
   2661   }
   2662 
   2663   void BranchIfNumberGreaterThan(Node* left, Node* right, Label* if_true,
   2664                                  Label* if_false) {
   2665     BranchIfNumberRelationalComparison(Operation::kGreaterThan, left, right,
   2666                                        if_true, if_false);
   2667   }
   2668 
   2669   void BranchIfNumberGreaterThanOrEqual(Node* left, Node* right, Label* if_true,
   2670                                         Label* if_false) {
   2671     BranchIfNumberRelationalComparison(Operation::kGreaterThanOrEqual, left,
   2672                                        right, if_true, if_false);
   2673   }
   2674 
   2675   void BranchIfAccessorPair(Node* value, Label* if_accessor_pair,
   2676                             Label* if_not_accessor_pair) {
   2677     GotoIf(TaggedIsSmi(value), if_not_accessor_pair);
   2678     Branch(IsAccessorPair(value), if_accessor_pair, if_not_accessor_pair);
   2679   }
   2680 
   2681   void GotoIfNumberGreaterThanOrEqual(Node* left, Node* right, Label* if_false);
   2682 
   2683   Node* Equal(Node* lhs, Node* rhs, Node* context,
   2684               Variable* var_type_feedback = nullptr);
   2685 
   2686   Node* StrictEqual(Node* lhs, Node* rhs,
   2687                     Variable* var_type_feedback = nullptr);
   2688 
   2689   // ECMA#sec-samevalue
   2690   // Similar to StrictEqual except that NaNs are treated as equal and minus zero
   2691   // differs from positive zero.
   2692   void BranchIfSameValue(Node* lhs, Node* rhs, Label* if_true, Label* if_false);
   2693 
   2694   enum HasPropertyLookupMode { kHasProperty, kForInHasProperty };
   2695 
   2696   TNode<Oddball> HasProperty(SloppyTNode<Context> context,
   2697                              SloppyTNode<Object> object,
   2698                              SloppyTNode<Object> key,
   2699                              HasPropertyLookupMode mode);
   2700 
   2701   Node* Typeof(Node* value);
   2702 
   2703   TNode<Object> GetSuperConstructor(SloppyTNode<Context> context,
   2704                                     SloppyTNode<JSFunction> active_function);
   2705 
   2706   TNode<Object> SpeciesConstructor(SloppyTNode<Context> context,
   2707                                    SloppyTNode<Object> object,
   2708                                    SloppyTNode<Object> default_constructor);
   2709 
   2710   Node* InstanceOf(Node* object, Node* callable, Node* context);
   2711 
   2712   // Debug helpers
   2713   Node* IsDebugActive();
   2714 
   2715   TNode<BoolT> IsRuntimeCallStatsEnabled();
   2716 
   2717   // TypedArray/ArrayBuffer helpers
   2718   Node* IsDetachedBuffer(Node* buffer);
   2719   void ThrowIfArrayBufferIsDetached(SloppyTNode<Context> context,
   2720                                     TNode<JSArrayBuffer> array_buffer,
   2721                                     const char* method_name);
   2722   void ThrowIfArrayBufferViewBufferIsDetached(
   2723       SloppyTNode<Context> context, TNode<JSArrayBufferView> array_buffer_view,
   2724       const char* method_name);
   2725   TNode<JSArrayBuffer> LoadArrayBufferViewBuffer(
   2726       TNode<JSArrayBufferView> array_buffer_view);
   2727   TNode<RawPtrT> LoadArrayBufferBackingStore(TNode<JSArrayBuffer> array_buffer);
   2728 
   2729   TNode<IntPtrT> ElementOffsetFromIndex(Node* index, ElementsKind kind,
   2730                                         ParameterMode mode, int base_size = 0);
   2731 
   2732   // Check that a field offset is within the bounds of the an object.
   2733   TNode<BoolT> IsOffsetInBounds(SloppyTNode<IntPtrT> offset,
   2734                                 SloppyTNode<IntPtrT> length, int header_size,
   2735                                 ElementsKind kind = HOLEY_ELEMENTS);
   2736 
   2737   // Load a builtin's code from the builtin array in the isolate.
   2738   TNode<Code> LoadBuiltin(TNode<Smi> builtin_id);
   2739 
   2740   // Figure out the SFI's code object using its data field.
   2741   // If |if_compile_lazy| is provided then the execution will go to the given
   2742   // label in case of an CompileLazy code object.
   2743   TNode<Code> GetSharedFunctionInfoCode(
   2744       SloppyTNode<SharedFunctionInfo> shared_info,
   2745       Label* if_compile_lazy = nullptr);
   2746 
   2747   Node* AllocateFunctionWithMapAndContext(Node* map, Node* shared_info,
   2748                                           Node* context);
   2749 
   2750   // Promise helpers
   2751   Node* IsPromiseHookEnabled();
   2752   Node* HasAsyncEventDelegate();
   2753   Node* IsPromiseHookEnabledOrHasAsyncEventDelegate();
   2754 
   2755   // Helpers for StackFrame markers.
   2756   Node* MarkerIsFrameType(Node* marker_or_function,
   2757                           StackFrame::Type frame_type);
   2758   Node* MarkerIsNotFrameType(Node* marker_or_function,
   2759                              StackFrame::Type frame_type);
   2760 
   2761   // for..in helpers
   2762   void CheckPrototypeEnumCache(Node* receiver, Node* receiver_map,
   2763                                Label* if_fast, Label* if_slow);
   2764   Node* CheckEnumCache(Node* receiver, Label* if_empty, Label* if_runtime);
   2765 
   2766   TNode<IntPtrT> GetArgumentsLength(CodeStubArguments* args);
   2767   TNode<Object> GetArgumentValue(CodeStubArguments* args, TNode<IntPtrT> index);
   2768 
   2769   // Support for printf-style debugging
   2770   void Print(const char* s);
   2771   void Print(const char* prefix, Node* tagged_value);
   2772   inline void Print(SloppyTNode<Object> tagged_value) {
   2773     return Print(nullptr, tagged_value);
   2774   }
   2775   inline void Print(TNode<MaybeObject> tagged_value) {
   2776     return Print(nullptr, tagged_value);
   2777   }
   2778 
   2779   template <class... TArgs>
   2780   Node* MakeTypeError(MessageTemplate::Template message, Node* context,
   2781                       TArgs... args) {
   2782     STATIC_ASSERT(sizeof...(TArgs) <= 3);
   2783     Node* const make_type_error = LoadContextElement(
   2784         LoadNativeContext(context), Context::MAKE_TYPE_ERROR_INDEX);
   2785     return CallJS(CodeFactory::Call(isolate()), context, make_type_error,
   2786                   UndefinedConstant(), SmiConstant(message), args...);
   2787   }
   2788 
   2789   void Abort(AbortReason reason) {
   2790     CallRuntime(Runtime::kAbort, NoContextConstant(), SmiConstant(reason));
   2791     Unreachable();
   2792   }
   2793 
   2794   bool ConstexprBoolNot(bool value) { return !value; }
   2795 
   2796   bool ConstexprInt31Equal(int31_t a, int31_t b) { return a == b; }
   2797 
   2798   void PerformStackCheck(TNode<Context> context);
   2799 
   2800  protected:
   2801   // Implements DescriptorArray::Search().
   2802   void DescriptorLookup(SloppyTNode<Name> unique_name,
   2803                         SloppyTNode<DescriptorArray> descriptors,
   2804                         SloppyTNode<Uint32T> bitfield3, Label* if_found,
   2805                         TVariable<IntPtrT>* var_name_index,
   2806                         Label* if_not_found);
   2807 
   2808   // Implements TransitionArray::SearchName() - searches for first transition
   2809   // entry with given name (note that there could be multiple entries with
   2810   // the same name).
   2811   void TransitionLookup(SloppyTNode<Name> unique_name,
   2812                         SloppyTNode<TransitionArray> transitions,
   2813                         Label* if_found, TVariable<IntPtrT>* var_name_index,
   2814                         Label* if_not_found);
   2815 
   2816   // Implements generic search procedure like i::Search<Array>().
   2817   template <typename Array>
   2818   void Lookup(TNode<Name> unique_name, TNode<Array> array,
   2819               TNode<Uint32T> number_of_valid_entries, Label* if_found,
   2820               TVariable<IntPtrT>* var_name_index, Label* if_not_found);
   2821 
   2822   // Implements generic linear search procedure like i::LinearSearch<Array>().
   2823   template <typename Array>
   2824   void LookupLinear(TNode<Name> unique_name, TNode<Array> array,
   2825                     TNode<Uint32T> number_of_valid_entries, Label* if_found,
   2826                     TVariable<IntPtrT>* var_name_index, Label* if_not_found);
   2827 
   2828   // Implements generic binary search procedure like i::BinarySearch<Array>().
   2829   template <typename Array>
   2830   void LookupBinary(TNode<Name> unique_name, TNode<Array> array,
   2831                     TNode<Uint32T> number_of_valid_entries, Label* if_found,
   2832                     TVariable<IntPtrT>* var_name_index, Label* if_not_found);
   2833 
   2834   // Converts [Descriptor/Transition]Array entry number to a fixed array index.
   2835   template <typename Array>
   2836   TNode<IntPtrT> EntryIndexToIndex(TNode<Uint32T> entry_index);
   2837 
   2838   // Implements [Descriptor/Transition]Array::ToKeyIndex.
   2839   template <typename Array>
   2840   TNode<IntPtrT> ToKeyIndex(TNode<Uint32T> entry_index);
   2841 
   2842   // Implements [Descriptor/Transition]Array::GetKey.
   2843   template <typename Array>
   2844   TNode<Name> GetKey(TNode<Array> array, TNode<Uint32T> entry_index);
   2845 
   2846   // Implements DescriptorArray::GetDetails.
   2847   TNode<Uint32T> DescriptorArrayGetDetails(TNode<DescriptorArray> descriptors,
   2848                                            TNode<Uint32T> descriptor_number);
   2849 
   2850   typedef std::function<void(TNode<UintPtrT> descriptor_key_index)>
   2851       ForEachDescriptorBodyFunction;
   2852 
   2853   void DescriptorArrayForEach(VariableList& variable_list,
   2854                               TNode<Uint32T> start_descriptor,
   2855                               TNode<Uint32T> end_descriptor,
   2856                               const ForEachDescriptorBodyFunction& body);
   2857 
   2858   TNode<Object> CallGetterIfAccessor(Node* value, Node* details, Node* context,
   2859                                      Node* receiver, Label* if_bailout,
   2860                                      GetOwnPropertyMode mode = kCallJSGetter);
   2861 
   2862   TNode<IntPtrT> TryToIntptr(Node* key, Label* miss);
   2863 
   2864   void BranchIfPrototypesHaveNoElements(Node* receiver_map,
   2865                                         Label* definitely_no_elements,
   2866                                         Label* possibly_elements);
   2867 
   2868   void InitializeFunctionContext(Node* native_context, Node* context,
   2869                                  int slots);
   2870 
   2871  private:
   2872   friend class CodeStubArguments;
   2873 
   2874   void HandleBreakOnNode();
   2875 
   2876   Node* AllocateRawDoubleAligned(Node* size_in_bytes, AllocationFlags flags,
   2877                                  Node* top_address, Node* limit_address);
   2878   Node* AllocateRawUnaligned(Node* size_in_bytes, AllocationFlags flags,
   2879                              Node* top_adddress, Node* limit_address);
   2880   Node* AllocateRaw(Node* size_in_bytes, AllocationFlags flags,
   2881                     Node* top_address, Node* limit_address);
   2882   // Allocate and return a JSArray of given total size in bytes with header
   2883   // fields initialized.
   2884   Node* AllocateUninitializedJSArray(Node* array_map, Node* length,
   2885                                      Node* allocation_site,
   2886                                      Node* size_in_bytes);
   2887 
   2888   TNode<BoolT> IsValidSmi(TNode<Smi> smi);
   2889   Node* SmiShiftBitsConstant();
   2890 
   2891   // Emits keyed sloppy arguments load if the |value| is nullptr or store
   2892   // otherwise. Returns either the loaded value or |value|.
   2893   Node* EmitKeyedSloppyArguments(Node* receiver, Node* key, Node* value,
   2894                                  Label* bailout);
   2895 
   2896   TNode<String> AllocateSlicedString(Heap::RootListIndex map_root_index,
   2897                                      TNode<Smi> length, TNode<String> parent,
   2898                                      TNode<Smi> offset);
   2899 
   2900   TNode<String> AllocateConsString(Heap::RootListIndex map_root_index,
   2901                                    TNode<Smi> length, TNode<String> first,
   2902                                    TNode<String> second, AllocationFlags flags);
   2903 
   2904   // Allocate a MutableHeapNumber without initializing its value.
   2905   TNode<MutableHeapNumber> AllocateMutableHeapNumber();
   2906 
   2907   Node* SelectImpl(TNode<BoolT> condition, const NodeGenerator& true_body,
   2908                    const NodeGenerator& false_body, MachineRepresentation rep);
   2909 
   2910   // Implements [Descriptor/Transition]Array::number_of_entries.
   2911   template <typename Array>
   2912   TNode<Uint32T> NumberOfEntries(TNode<Array> array);
   2913 
   2914   // Implements [Descriptor/Transition]Array::GetSortedKeyIndex.
   2915   template <typename Array>
   2916   TNode<Uint32T> GetSortedKeyIndex(TNode<Array> descriptors,
   2917                                    TNode<Uint32T> entry_index);
   2918 
   2919   TNode<Smi> CollectFeedbackForString(SloppyTNode<Int32T> instance_type);
   2920   void GenerateEqual_Same(Node* value, Label* if_equal, Label* if_notequal,
   2921                           Variable* var_type_feedback = nullptr);
   2922   TNode<String> AllocAndCopyStringCharacters(Node* from,
   2923                                              Node* from_instance_type,
   2924                                              TNode<IntPtrT> from_index,
   2925                                              TNode<Smi> character_count);
   2926 
   2927   static const int kElementLoopUnrollThreshold = 8;
   2928 
   2929   // {convert_bigint} is only meaningful when {mode} == kToNumber.
   2930   Node* NonNumberToNumberOrNumeric(
   2931       Node* context, Node* input, Object::Conversion mode,
   2932       BigIntHandling bigint_handling = BigIntHandling::kThrow);
   2933 
   2934   void TaggedToNumeric(Node* context, Node* value, Label* done,
   2935                        Variable* var_numeric, Variable* var_feedback);
   2936 
   2937   template <Object::Conversion conversion>
   2938   void TaggedToWord32OrBigIntImpl(Node* context, Node* value, Label* if_number,
   2939                                   Variable* var_word32,
   2940                                   Label* if_bigint = nullptr,
   2941                                   Variable* var_bigint = nullptr,
   2942                                   Variable* var_feedback = nullptr);
   2943 };
   2944 
   2945 class CodeStubArguments {
   2946  public:
   2947   typedef compiler::Node Node;
   2948   template <class T>
   2949   using TNode = compiler::TNode<T>;
   2950   template <class T>
   2951   using SloppyTNode = compiler::SloppyTNode<T>;
   2952   enum ReceiverMode { kHasReceiver, kNoReceiver };
   2953 
   2954   // |argc| is an intptr value which specifies the number of arguments passed
   2955   // to the builtin excluding the receiver. The arguments will include a
   2956   // receiver iff |receiver_mode| is kHasReceiver.
   2957   CodeStubArguments(CodeStubAssembler* assembler, Node* argc,
   2958                     ReceiverMode receiver_mode = ReceiverMode::kHasReceiver)
   2959       : CodeStubArguments(assembler, argc, nullptr,
   2960                           CodeStubAssembler::INTPTR_PARAMETERS, receiver_mode) {
   2961   }
   2962 
   2963   // |argc| is either a smi or intptr depending on |param_mode|. The arguments
   2964   // include a receiver iff |receiver_mode| is kHasReceiver.
   2965   CodeStubArguments(CodeStubAssembler* assembler, Node* argc, Node* fp,
   2966                     CodeStubAssembler::ParameterMode param_mode,
   2967                     ReceiverMode receiver_mode = ReceiverMode::kHasReceiver);
   2968 
   2969   TNode<Object> GetReceiver() const;
   2970   // Replaces receiver argument on the expression stack. Should be used only
   2971   // for manipulating arguments in trampoline builtins before tail calling
   2972   // further with passing all the JS arguments as is.
   2973   void SetReceiver(TNode<Object> object) const;
   2974 
   2975   TNode<RawPtr<Object>> AtIndexPtr(
   2976       Node* index, CodeStubAssembler::ParameterMode mode =
   2977                        CodeStubAssembler::INTPTR_PARAMETERS) const;
   2978 
   2979   // |index| is zero-based and does not include the receiver
   2980   TNode<Object> AtIndex(Node* index,
   2981                         CodeStubAssembler::ParameterMode mode =
   2982                             CodeStubAssembler::INTPTR_PARAMETERS) const;
   2983 
   2984   TNode<Object> AtIndex(int index) const;
   2985 
   2986   TNode<Object> GetOptionalArgumentValue(int index) {
   2987     return GetOptionalArgumentValue(index, assembler_->UndefinedConstant());
   2988   }
   2989   TNode<Object> GetOptionalArgumentValue(int index,
   2990                                          TNode<Object> default_value);
   2991 
   2992   Node* GetLength(CodeStubAssembler::ParameterMode mode) const {
   2993     DCHECK_EQ(mode, argc_mode_);
   2994     return argc_;
   2995   }
   2996 
   2997   TNode<Object> GetOptionalArgumentValue(TNode<IntPtrT> index) {
   2998     return GetOptionalArgumentValue(index, assembler_->UndefinedConstant());
   2999   }
   3000   TNode<Object> GetOptionalArgumentValue(TNode<IntPtrT> index,
   3001                                          TNode<Object> default_value);
   3002   TNode<IntPtrT> GetLength() const {
   3003     DCHECK_EQ(argc_mode_, CodeStubAssembler::INTPTR_PARAMETERS);
   3004     return assembler_->UncheckedCast<IntPtrT>(argc_);
   3005   }
   3006 
   3007   typedef std::function<void(Node* arg)> ForEachBodyFunction;
   3008 
   3009   // Iteration doesn't include the receiver. |first| and |last| are zero-based.
   3010   void ForEach(const ForEachBodyFunction& body, Node* first = nullptr,
   3011                Node* last = nullptr,
   3012                CodeStubAssembler::ParameterMode mode =
   3013                    CodeStubAssembler::INTPTR_PARAMETERS) {
   3014     CodeStubAssembler::VariableList list(0, assembler_->zone());
   3015     ForEach(list, body, first, last);
   3016   }
   3017 
   3018   // Iteration doesn't include the receiver. |first| and |last| are zero-based.
   3019   void ForEach(const CodeStubAssembler::VariableList& vars,
   3020                const ForEachBodyFunction& body, Node* first = nullptr,
   3021                Node* last = nullptr,
   3022                CodeStubAssembler::ParameterMode mode =
   3023                    CodeStubAssembler::INTPTR_PARAMETERS);
   3024 
   3025   void PopAndReturn(Node* value);
   3026 
   3027  private:
   3028   Node* GetArguments();
   3029 
   3030   CodeStubAssembler* assembler_;
   3031   CodeStubAssembler::ParameterMode argc_mode_;
   3032   ReceiverMode receiver_mode_;
   3033   Node* argc_;
   3034   TNode<RawPtr<Object>> arguments_;
   3035   Node* fp_;
   3036 };
   3037 
   3038 class ToDirectStringAssembler : public CodeStubAssembler {
   3039  private:
   3040   enum StringPointerKind { PTR_TO_DATA, PTR_TO_STRING };
   3041 
   3042  public:
   3043   enum Flag {
   3044     kDontUnpackSlicedStrings = 1 << 0,
   3045   };
   3046   typedef base::Flags<Flag> Flags;
   3047 
   3048   ToDirectStringAssembler(compiler::CodeAssemblerState* state, Node* string,
   3049                           Flags flags = Flags());
   3050 
   3051   // Converts flat cons, thin, and sliced strings and returns the direct
   3052   // string. The result can be either a sequential or external string.
   3053   // Jumps to if_bailout if the string if the string is indirect and cannot
   3054   // be unpacked.
   3055   TNode<String> TryToDirect(Label* if_bailout);
   3056 
   3057   // Returns a pointer to the beginning of the string data.
   3058   // Jumps to if_bailout if the external string cannot be unpacked.
   3059   TNode<RawPtrT> PointerToData(Label* if_bailout) {
   3060     return TryToSequential(PTR_TO_DATA, if_bailout);
   3061   }
   3062 
   3063   // Returns a pointer that, offset-wise, looks like a String.
   3064   // Jumps to if_bailout if the external string cannot be unpacked.
   3065   TNode<RawPtrT> PointerToString(Label* if_bailout) {
   3066     return TryToSequential(PTR_TO_STRING, if_bailout);
   3067   }
   3068 
   3069   Node* string() { return var_string_.value(); }
   3070   Node* instance_type() { return var_instance_type_.value(); }
   3071   TNode<IntPtrT> offset() {
   3072     return UncheckedCast<IntPtrT>(var_offset_.value());
   3073   }
   3074   Node* is_external() { return var_is_external_.value(); }
   3075 
   3076  private:
   3077   TNode<RawPtrT> TryToSequential(StringPointerKind ptr_kind, Label* if_bailout);
   3078 
   3079   Variable var_string_;
   3080   Variable var_instance_type_;
   3081   Variable var_offset_;
   3082   Variable var_is_external_;
   3083 
   3084   const Flags flags_;
   3085 };
   3086 
   3087 
   3088 DEFINE_OPERATORS_FOR_FLAGS(CodeStubAssembler::AllocationFlags);
   3089 
   3090 }  // namespace internal
   3091 }  // namespace v8
   3092 #endif  // V8_CODE_STUB_ASSEMBLER_H_
   3093