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1 // Copyright 2012 the V8 project authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4 
5 #include "src/ast/ast.h"
6 
7 #include <cmath>  // For isfinite.
8 #include "src/ast/scopes.h"
9 #include "src/builtins.h"
10 #include "src/code-stubs.h"
11 #include "src/contexts.h"
12 #include "src/conversions.h"
13 #include "src/hashmap.h"
14 #include "src/parsing/parser.h"
15 #include "src/property.h"
16 #include "src/property-details.h"
17 #include "src/string-stream.h"
18 #include "src/type-info.h"
19 
20 namespace v8 {
21 namespace internal {
22 
23 // ----------------------------------------------------------------------------
24 // All the Accept member functions for each syntax tree node type.
25 
26 #define DECL_ACCEPT(type)                                       \
27   void type::Accept(AstVisitor* v) { v->Visit##type(this); }
AST_NODE_LIST(DECL_ACCEPT)28 AST_NODE_LIST(DECL_ACCEPT)
29 #undef DECL_ACCEPT
30 
31 
32 // ----------------------------------------------------------------------------
33 // Implementation of other node functionality.
34 
35 
36 bool Expression::IsSmiLiteral() const {
37   return IsLiteral() && AsLiteral()->value()->IsSmi();
38 }
39 
40 
IsStringLiteral() const41 bool Expression::IsStringLiteral() const {
42   return IsLiteral() && AsLiteral()->value()->IsString();
43 }
44 
45 
IsNullLiteral() const46 bool Expression::IsNullLiteral() const {
47   return IsLiteral() && AsLiteral()->value()->IsNull();
48 }
49 
50 
IsUndefinedLiteral(Isolate * isolate) const51 bool Expression::IsUndefinedLiteral(Isolate* isolate) const {
52   const VariableProxy* var_proxy = AsVariableProxy();
53   if (var_proxy == NULL) return false;
54   Variable* var = var_proxy->var();
55   // The global identifier "undefined" is immutable. Everything
56   // else could be reassigned.
57   return var != NULL && var->IsUnallocatedOrGlobalSlot() &&
58          var_proxy->raw_name()->IsOneByteEqualTo("undefined");
59 }
60 
61 
IsValidReferenceExpressionOrThis() const62 bool Expression::IsValidReferenceExpressionOrThis() const {
63   return IsValidReferenceExpression() ||
64          (IsVariableProxy() && AsVariableProxy()->is_this());
65 }
66 
67 
VariableProxy(Zone * zone,Variable * var,int start_position,int end_position)68 VariableProxy::VariableProxy(Zone* zone, Variable* var, int start_position,
69                              int end_position)
70     : Expression(zone, start_position),
71       bit_field_(IsThisField::encode(var->is_this()) |
72                  IsAssignedField::encode(false) |
73                  IsResolvedField::encode(false)),
74       raw_name_(var->raw_name()),
75       end_position_(end_position) {
76   BindTo(var);
77 }
78 
79 
VariableProxy(Zone * zone,const AstRawString * name,Variable::Kind variable_kind,int start_position,int end_position)80 VariableProxy::VariableProxy(Zone* zone, const AstRawString* name,
81                              Variable::Kind variable_kind, int start_position,
82                              int end_position)
83     : Expression(zone, start_position),
84       bit_field_(IsThisField::encode(variable_kind == Variable::THIS) |
85                  IsAssignedField::encode(false) |
86                  IsResolvedField::encode(false)),
87       raw_name_(name),
88       end_position_(end_position) {}
89 
90 
BindTo(Variable * var)91 void VariableProxy::BindTo(Variable* var) {
92   DCHECK((is_this() && var->is_this()) || raw_name() == var->raw_name());
93   set_var(var);
94   set_is_resolved();
95   var->set_is_used();
96 }
97 
98 
AssignFeedbackVectorSlots(Isolate * isolate,FeedbackVectorSpec * spec,FeedbackVectorSlotCache * cache)99 void VariableProxy::AssignFeedbackVectorSlots(Isolate* isolate,
100                                               FeedbackVectorSpec* spec,
101                                               FeedbackVectorSlotCache* cache) {
102   if (UsesVariableFeedbackSlot()) {
103     // VariableProxies that point to the same Variable within a function can
104     // make their loads from the same IC slot.
105     if (var()->IsUnallocated()) {
106       ZoneHashMap::Entry* entry = cache->Get(var());
107       if (entry != NULL) {
108         variable_feedback_slot_ = FeedbackVectorSlot(
109             static_cast<int>(reinterpret_cast<intptr_t>(entry->value)));
110         return;
111       }
112     }
113     variable_feedback_slot_ = spec->AddLoadICSlot();
114     if (var()->IsUnallocated()) {
115       cache->Put(var(), variable_feedback_slot_);
116     }
117   }
118 }
119 
120 
AssignVectorSlots(Expression * expr,FeedbackVectorSpec * spec,FeedbackVectorSlot * out_slot)121 static void AssignVectorSlots(Expression* expr, FeedbackVectorSpec* spec,
122                               FeedbackVectorSlot* out_slot) {
123   Property* property = expr->AsProperty();
124   LhsKind assign_type = Property::GetAssignType(property);
125   if ((assign_type == VARIABLE &&
126        expr->AsVariableProxy()->var()->IsUnallocated()) ||
127       assign_type == NAMED_PROPERTY || assign_type == KEYED_PROPERTY) {
128     // TODO(ishell): consider using ICSlotCache for variables here.
129     FeedbackVectorSlotKind kind = assign_type == KEYED_PROPERTY
130                                       ? FeedbackVectorSlotKind::KEYED_STORE_IC
131                                       : FeedbackVectorSlotKind::STORE_IC;
132     *out_slot = spec->AddSlot(kind);
133   }
134 }
135 
136 
AssignFeedbackVectorSlots(Isolate * isolate,FeedbackVectorSpec * spec,FeedbackVectorSlotCache * cache)137 void ForEachStatement::AssignFeedbackVectorSlots(
138     Isolate* isolate, FeedbackVectorSpec* spec,
139     FeedbackVectorSlotCache* cache) {
140   // TODO(adamk): for-of statements do not make use of this feedback slot.
141   // The each_slot_ should be specific to ForInStatement, and this work moved
142   // there.
143   if (IsForOfStatement()) return;
144   AssignVectorSlots(each(), spec, &each_slot_);
145 }
146 
147 
Assignment(Zone * zone,Token::Value op,Expression * target,Expression * value,int pos)148 Assignment::Assignment(Zone* zone, Token::Value op, Expression* target,
149                        Expression* value, int pos)
150     : Expression(zone, pos),
151       bit_field_(
152           IsUninitializedField::encode(false) | KeyTypeField::encode(ELEMENT) |
153           StoreModeField::encode(STANDARD_STORE) | TokenField::encode(op)),
154       target_(target),
155       value_(value),
156       binary_operation_(NULL) {}
157 
158 
AssignFeedbackVectorSlots(Isolate * isolate,FeedbackVectorSpec * spec,FeedbackVectorSlotCache * cache)159 void Assignment::AssignFeedbackVectorSlots(Isolate* isolate,
160                                            FeedbackVectorSpec* spec,
161                                            FeedbackVectorSlotCache* cache) {
162   AssignVectorSlots(target(), spec, &slot_);
163 }
164 
165 
AssignFeedbackVectorSlots(Isolate * isolate,FeedbackVectorSpec * spec,FeedbackVectorSlotCache * cache)166 void CountOperation::AssignFeedbackVectorSlots(Isolate* isolate,
167                                                FeedbackVectorSpec* spec,
168                                                FeedbackVectorSlotCache* cache) {
169   AssignVectorSlots(expression(), spec, &slot_);
170 }
171 
172 
binary_op() const173 Token::Value Assignment::binary_op() const {
174   switch (op()) {
175     case Token::ASSIGN_BIT_OR: return Token::BIT_OR;
176     case Token::ASSIGN_BIT_XOR: return Token::BIT_XOR;
177     case Token::ASSIGN_BIT_AND: return Token::BIT_AND;
178     case Token::ASSIGN_SHL: return Token::SHL;
179     case Token::ASSIGN_SAR: return Token::SAR;
180     case Token::ASSIGN_SHR: return Token::SHR;
181     case Token::ASSIGN_ADD: return Token::ADD;
182     case Token::ASSIGN_SUB: return Token::SUB;
183     case Token::ASSIGN_MUL: return Token::MUL;
184     case Token::ASSIGN_DIV: return Token::DIV;
185     case Token::ASSIGN_MOD: return Token::MOD;
186     default: UNREACHABLE();
187   }
188   return Token::ILLEGAL;
189 }
190 
191 
AllowsLazyCompilation()192 bool FunctionLiteral::AllowsLazyCompilation() {
193   return scope()->AllowsLazyCompilation();
194 }
195 
196 
AllowsLazyCompilationWithoutContext()197 bool FunctionLiteral::AllowsLazyCompilationWithoutContext() {
198   return scope()->AllowsLazyCompilationWithoutContext();
199 }
200 
201 
start_position() const202 int FunctionLiteral::start_position() const {
203   return scope()->start_position();
204 }
205 
206 
end_position() const207 int FunctionLiteral::end_position() const {
208   return scope()->end_position();
209 }
210 
211 
language_mode() const212 LanguageMode FunctionLiteral::language_mode() const {
213   return scope()->language_mode();
214 }
215 
216 
NeedsHomeObject(Expression * expr)217 bool FunctionLiteral::NeedsHomeObject(Expression* expr) {
218   if (expr == nullptr || !expr->IsFunctionLiteral()) return false;
219   DCHECK_NOT_NULL(expr->AsFunctionLiteral()->scope());
220   return expr->AsFunctionLiteral()->scope()->NeedsHomeObject();
221 }
222 
223 
ObjectLiteralProperty(Expression * key,Expression * value,Kind kind,bool is_static,bool is_computed_name)224 ObjectLiteralProperty::ObjectLiteralProperty(Expression* key, Expression* value,
225                                              Kind kind, bool is_static,
226                                              bool is_computed_name)
227     : key_(key),
228       value_(value),
229       kind_(kind),
230       emit_store_(true),
231       is_static_(is_static),
232       is_computed_name_(is_computed_name) {}
233 
234 
ObjectLiteralProperty(AstValueFactory * ast_value_factory,Expression * key,Expression * value,bool is_static,bool is_computed_name)235 ObjectLiteralProperty::ObjectLiteralProperty(AstValueFactory* ast_value_factory,
236                                              Expression* key, Expression* value,
237                                              bool is_static,
238                                              bool is_computed_name)
239     : key_(key),
240       value_(value),
241       emit_store_(true),
242       is_static_(is_static),
243       is_computed_name_(is_computed_name) {
244   if (!is_computed_name &&
245       key->AsLiteral()->raw_value()->EqualsString(
246           ast_value_factory->proto_string())) {
247     kind_ = PROTOTYPE;
248   } else if (value_->AsMaterializedLiteral() != NULL) {
249     kind_ = MATERIALIZED_LITERAL;
250   } else if (value_->IsLiteral()) {
251     kind_ = CONSTANT;
252   } else {
253     kind_ = COMPUTED;
254   }
255 }
256 
257 
AssignFeedbackVectorSlots(Isolate * isolate,FeedbackVectorSpec * spec,FeedbackVectorSlotCache * cache)258 void ClassLiteral::AssignFeedbackVectorSlots(Isolate* isolate,
259                                              FeedbackVectorSpec* spec,
260                                              FeedbackVectorSlotCache* cache) {
261   // This logic that computes the number of slots needed for vector store
262   // ICs must mirror FullCodeGenerator::VisitClassLiteral.
263   if (NeedsProxySlot()) {
264     slot_ = spec->AddStoreICSlot();
265   }
266 
267   for (int i = 0; i < properties()->length(); i++) {
268     ObjectLiteral::Property* property = properties()->at(i);
269     Expression* value = property->value();
270     if (FunctionLiteral::NeedsHomeObject(value)) {
271       property->SetSlot(spec->AddStoreICSlot());
272     }
273   }
274 }
275 
276 
IsCompileTimeValue()277 bool ObjectLiteral::Property::IsCompileTimeValue() {
278   return kind_ == CONSTANT ||
279       (kind_ == MATERIALIZED_LITERAL &&
280        CompileTimeValue::IsCompileTimeValue(value_));
281 }
282 
283 
set_emit_store(bool emit_store)284 void ObjectLiteral::Property::set_emit_store(bool emit_store) {
285   emit_store_ = emit_store;
286 }
287 
288 
emit_store()289 bool ObjectLiteral::Property::emit_store() {
290   return emit_store_;
291 }
292 
293 
AssignFeedbackVectorSlots(Isolate * isolate,FeedbackVectorSpec * spec,FeedbackVectorSlotCache * cache)294 void ObjectLiteral::AssignFeedbackVectorSlots(Isolate* isolate,
295                                               FeedbackVectorSpec* spec,
296                                               FeedbackVectorSlotCache* cache) {
297   // This logic that computes the number of slots needed for vector store
298   // ics must mirror FullCodeGenerator::VisitObjectLiteral.
299   int property_index = 0;
300   for (; property_index < properties()->length(); property_index++) {
301     ObjectLiteral::Property* property = properties()->at(property_index);
302     if (property->is_computed_name()) break;
303     if (property->IsCompileTimeValue()) continue;
304 
305     Literal* key = property->key()->AsLiteral();
306     Expression* value = property->value();
307     switch (property->kind()) {
308       case ObjectLiteral::Property::CONSTANT:
309         UNREACHABLE();
310       case ObjectLiteral::Property::MATERIALIZED_LITERAL:
311       // Fall through.
312       case ObjectLiteral::Property::COMPUTED:
313         // It is safe to use [[Put]] here because the boilerplate already
314         // contains computed properties with an uninitialized value.
315         if (key->value()->IsInternalizedString()) {
316           if (property->emit_store()) {
317             property->SetSlot(spec->AddStoreICSlot());
318             if (FunctionLiteral::NeedsHomeObject(value)) {
319               property->SetSlot(spec->AddStoreICSlot(), 1);
320             }
321           }
322           break;
323         }
324         if (property->emit_store() && FunctionLiteral::NeedsHomeObject(value)) {
325           property->SetSlot(spec->AddStoreICSlot());
326         }
327         break;
328       case ObjectLiteral::Property::PROTOTYPE:
329         break;
330       case ObjectLiteral::Property::GETTER:
331         if (property->emit_store() && FunctionLiteral::NeedsHomeObject(value)) {
332           property->SetSlot(spec->AddStoreICSlot());
333         }
334         break;
335       case ObjectLiteral::Property::SETTER:
336         if (property->emit_store() && FunctionLiteral::NeedsHomeObject(value)) {
337           property->SetSlot(spec->AddStoreICSlot());
338         }
339         break;
340     }
341   }
342 
343   for (; property_index < properties()->length(); property_index++) {
344     ObjectLiteral::Property* property = properties()->at(property_index);
345 
346     Expression* value = property->value();
347     if (property->kind() != ObjectLiteral::Property::PROTOTYPE) {
348       if (FunctionLiteral::NeedsHomeObject(value)) {
349         property->SetSlot(spec->AddStoreICSlot());
350       }
351     }
352   }
353 }
354 
355 
CalculateEmitStore(Zone * zone)356 void ObjectLiteral::CalculateEmitStore(Zone* zone) {
357   const auto GETTER = ObjectLiteral::Property::GETTER;
358   const auto SETTER = ObjectLiteral::Property::SETTER;
359 
360   ZoneAllocationPolicy allocator(zone);
361 
362   ZoneHashMap table(Literal::Match, ZoneHashMap::kDefaultHashMapCapacity,
363                     allocator);
364   for (int i = properties()->length() - 1; i >= 0; i--) {
365     ObjectLiteral::Property* property = properties()->at(i);
366     if (property->is_computed_name()) continue;
367     if (property->kind() == ObjectLiteral::Property::PROTOTYPE) continue;
368     Literal* literal = property->key()->AsLiteral();
369     DCHECK(!literal->value()->IsNull());
370 
371     // If there is an existing entry do not emit a store unless the previous
372     // entry was also an accessor.
373     uint32_t hash = literal->Hash();
374     ZoneHashMap::Entry* entry = table.LookupOrInsert(literal, hash, allocator);
375     if (entry->value != NULL) {
376       auto previous_kind =
377           static_cast<ObjectLiteral::Property*>(entry->value)->kind();
378       if (!((property->kind() == GETTER && previous_kind == SETTER) ||
379             (property->kind() == SETTER && previous_kind == GETTER))) {
380         property->set_emit_store(false);
381       }
382     }
383     entry->value = property;
384   }
385 }
386 
387 
IsBoilerplateProperty(ObjectLiteral::Property * property)388 bool ObjectLiteral::IsBoilerplateProperty(ObjectLiteral::Property* property) {
389   return property != NULL &&
390          property->kind() != ObjectLiteral::Property::PROTOTYPE;
391 }
392 
393 
BuildConstantProperties(Isolate * isolate)394 void ObjectLiteral::BuildConstantProperties(Isolate* isolate) {
395   if (!constant_properties_.is_null()) return;
396 
397   // Allocate a fixed array to hold all the constant properties.
398   Handle<FixedArray> constant_properties = isolate->factory()->NewFixedArray(
399       boilerplate_properties_ * 2, TENURED);
400 
401   int position = 0;
402   // Accumulate the value in local variables and store it at the end.
403   bool is_simple = true;
404   int depth_acc = 1;
405   uint32_t max_element_index = 0;
406   uint32_t elements = 0;
407   for (int i = 0; i < properties()->length(); i++) {
408     ObjectLiteral::Property* property = properties()->at(i);
409     if (!IsBoilerplateProperty(property)) {
410       is_simple = false;
411       continue;
412     }
413 
414     if (position == boilerplate_properties_ * 2) {
415       DCHECK(property->is_computed_name());
416       is_simple = false;
417       break;
418     }
419     DCHECK(!property->is_computed_name());
420 
421     MaterializedLiteral* m_literal = property->value()->AsMaterializedLiteral();
422     if (m_literal != NULL) {
423       m_literal->BuildConstants(isolate);
424       if (m_literal->depth() >= depth_acc) depth_acc = m_literal->depth() + 1;
425     }
426 
427     // Add CONSTANT and COMPUTED properties to boilerplate. Use undefined
428     // value for COMPUTED properties, the real value is filled in at
429     // runtime. The enumeration order is maintained.
430     Handle<Object> key = property->key()->AsLiteral()->value();
431     Handle<Object> value = GetBoilerplateValue(property->value(), isolate);
432 
433     // Ensure objects that may, at any point in time, contain fields with double
434     // representation are always treated as nested objects. This is true for
435     // computed fields (value is undefined), and smi and double literals
436     // (value->IsNumber()).
437     // TODO(verwaest): Remove once we can store them inline.
438     if (FLAG_track_double_fields &&
439         (value->IsNumber() || value->IsUninitialized())) {
440       may_store_doubles_ = true;
441     }
442 
443     is_simple = is_simple && !value->IsUninitialized();
444 
445     // Keep track of the number of elements in the object literal and
446     // the largest element index.  If the largest element index is
447     // much larger than the number of elements, creating an object
448     // literal with fast elements will be a waste of space.
449     uint32_t element_index = 0;
450     if (key->IsString()
451         && Handle<String>::cast(key)->AsArrayIndex(&element_index)
452         && element_index > max_element_index) {
453       max_element_index = element_index;
454       elements++;
455     } else if (key->IsSmi()) {
456       int key_value = Smi::cast(*key)->value();
457       if (key_value > 0
458           && static_cast<uint32_t>(key_value) > max_element_index) {
459         max_element_index = key_value;
460       }
461       elements++;
462     }
463 
464     // Add name, value pair to the fixed array.
465     constant_properties->set(position++, *key);
466     constant_properties->set(position++, *value);
467   }
468 
469   constant_properties_ = constant_properties;
470   fast_elements_ =
471       (max_element_index <= 32) || ((2 * elements) >= max_element_index);
472   has_elements_ = elements > 0;
473   set_is_simple(is_simple);
474   set_depth(depth_acc);
475 }
476 
477 
BuildConstantElements(Isolate * isolate)478 void ArrayLiteral::BuildConstantElements(Isolate* isolate) {
479   if (!constant_elements_.is_null()) return;
480 
481   int constants_length =
482       first_spread_index_ >= 0 ? first_spread_index_ : values()->length();
483 
484   // Allocate a fixed array to hold all the object literals.
485   Handle<JSArray> array = isolate->factory()->NewJSArray(
486       FAST_HOLEY_SMI_ELEMENTS, constants_length, constants_length,
487       Strength::WEAK, INITIALIZE_ARRAY_ELEMENTS_WITH_HOLE);
488 
489   // Fill in the literals.
490   bool is_simple = (first_spread_index_ < 0);
491   int depth_acc = 1;
492   bool is_holey = false;
493   int array_index = 0;
494   for (; array_index < constants_length; array_index++) {
495     Expression* element = values()->at(array_index);
496     DCHECK(!element->IsSpread());
497     MaterializedLiteral* m_literal = element->AsMaterializedLiteral();
498     if (m_literal != NULL) {
499       m_literal->BuildConstants(isolate);
500       if (m_literal->depth() + 1 > depth_acc) {
501         depth_acc = m_literal->depth() + 1;
502       }
503     }
504 
505     // New handle scope here, needs to be after BuildContants().
506     HandleScope scope(isolate);
507     Handle<Object> boilerplate_value = GetBoilerplateValue(element, isolate);
508     if (boilerplate_value->IsTheHole()) {
509       is_holey = true;
510       continue;
511     }
512 
513     if (boilerplate_value->IsUninitialized()) {
514       boilerplate_value = handle(Smi::FromInt(0), isolate);
515       is_simple = false;
516     }
517 
518     JSObject::AddDataElement(array, array_index, boilerplate_value, NONE)
519         .Assert();
520   }
521 
522   JSObject::ValidateElements(array);
523   Handle<FixedArrayBase> element_values(array->elements());
524 
525   // Simple and shallow arrays can be lazily copied, we transform the
526   // elements array to a copy-on-write array.
527   if (is_simple && depth_acc == 1 && array_index > 0 &&
528       array->HasFastSmiOrObjectElements()) {
529     element_values->set_map(isolate->heap()->fixed_cow_array_map());
530   }
531 
532   // Remember both the literal's constant values as well as the ElementsKind
533   // in a 2-element FixedArray.
534   Handle<FixedArray> literals = isolate->factory()->NewFixedArray(2, TENURED);
535 
536   ElementsKind kind = array->GetElementsKind();
537   kind = is_holey ? GetHoleyElementsKind(kind) : GetPackedElementsKind(kind);
538 
539   literals->set(0, Smi::FromInt(kind));
540   literals->set(1, *element_values);
541 
542   constant_elements_ = literals;
543   set_is_simple(is_simple);
544   set_depth(depth_acc);
545 }
546 
547 
AssignFeedbackVectorSlots(Isolate * isolate,FeedbackVectorSpec * spec,FeedbackVectorSlotCache * cache)548 void ArrayLiteral::AssignFeedbackVectorSlots(Isolate* isolate,
549                                              FeedbackVectorSpec* spec,
550                                              FeedbackVectorSlotCache* cache) {
551   // This logic that computes the number of slots needed for vector store
552   // ics must mirror FullCodeGenerator::VisitArrayLiteral.
553   int array_index = 0;
554   for (; array_index < values()->length(); array_index++) {
555     Expression* subexpr = values()->at(array_index);
556     if (subexpr->IsSpread()) break;
557     if (CompileTimeValue::IsCompileTimeValue(subexpr)) continue;
558 
559     // We'll reuse the same literal slot for all of the non-constant
560     // subexpressions that use a keyed store IC.
561     literal_slot_ = spec->AddKeyedStoreICSlot();
562     return;
563   }
564 }
565 
566 
GetBoilerplateValue(Expression * expression,Isolate * isolate)567 Handle<Object> MaterializedLiteral::GetBoilerplateValue(Expression* expression,
568                                                         Isolate* isolate) {
569   if (expression->IsLiteral()) {
570     return expression->AsLiteral()->value();
571   }
572   if (CompileTimeValue::IsCompileTimeValue(expression)) {
573     return CompileTimeValue::GetValue(isolate, expression);
574   }
575   return isolate->factory()->uninitialized_value();
576 }
577 
578 
BuildConstants(Isolate * isolate)579 void MaterializedLiteral::BuildConstants(Isolate* isolate) {
580   if (IsArrayLiteral()) {
581     return AsArrayLiteral()->BuildConstantElements(isolate);
582   }
583   if (IsObjectLiteral()) {
584     return AsObjectLiteral()->BuildConstantProperties(isolate);
585   }
586   DCHECK(IsRegExpLiteral());
587   DCHECK(depth() >= 1);  // Depth should be initialized.
588 }
589 
590 
RecordToBooleanTypeFeedback(TypeFeedbackOracle * oracle)591 void UnaryOperation::RecordToBooleanTypeFeedback(TypeFeedbackOracle* oracle) {
592   // TODO(olivf) If this Operation is used in a test context, then the
593   // expression has a ToBoolean stub and we want to collect the type
594   // information. However the GraphBuilder expects it to be on the instruction
595   // corresponding to the TestContext, therefore we have to store it here and
596   // not on the operand.
597   set_to_boolean_types(oracle->ToBooleanTypes(expression()->test_id()));
598 }
599 
600 
RecordToBooleanTypeFeedback(TypeFeedbackOracle * oracle)601 void BinaryOperation::RecordToBooleanTypeFeedback(TypeFeedbackOracle* oracle) {
602   // TODO(olivf) If this Operation is used in a test context, then the right
603   // hand side has a ToBoolean stub and we want to collect the type information.
604   // However the GraphBuilder expects it to be on the instruction corresponding
605   // to the TestContext, therefore we have to store it here and not on the
606   // right hand operand.
607   set_to_boolean_types(oracle->ToBooleanTypes(right()->test_id()));
608 }
609 
610 
IsTypeof(Expression * expr)611 static bool IsTypeof(Expression* expr) {
612   UnaryOperation* maybe_unary = expr->AsUnaryOperation();
613   return maybe_unary != NULL && maybe_unary->op() == Token::TYPEOF;
614 }
615 
616 
617 // Check for the pattern: typeof <expression> equals <string literal>.
MatchLiteralCompareTypeof(Expression * left,Token::Value op,Expression * right,Expression ** expr,Handle<String> * check)618 static bool MatchLiteralCompareTypeof(Expression* left,
619                                       Token::Value op,
620                                       Expression* right,
621                                       Expression** expr,
622                                       Handle<String>* check) {
623   if (IsTypeof(left) && right->IsStringLiteral() && Token::IsEqualityOp(op)) {
624     *expr = left->AsUnaryOperation()->expression();
625     *check = Handle<String>::cast(right->AsLiteral()->value());
626     return true;
627   }
628   return false;
629 }
630 
631 
IsLiteralCompareTypeof(Expression ** expr,Handle<String> * check)632 bool CompareOperation::IsLiteralCompareTypeof(Expression** expr,
633                                               Handle<String>* check) {
634   return MatchLiteralCompareTypeof(left_, op_, right_, expr, check) ||
635       MatchLiteralCompareTypeof(right_, op_, left_, expr, check);
636 }
637 
638 
IsVoidOfLiteral(Expression * expr)639 static bool IsVoidOfLiteral(Expression* expr) {
640   UnaryOperation* maybe_unary = expr->AsUnaryOperation();
641   return maybe_unary != NULL &&
642       maybe_unary->op() == Token::VOID &&
643       maybe_unary->expression()->IsLiteral();
644 }
645 
646 
647 // Check for the pattern: void <literal> equals <expression> or
648 // undefined equals <expression>
MatchLiteralCompareUndefined(Expression * left,Token::Value op,Expression * right,Expression ** expr,Isolate * isolate)649 static bool MatchLiteralCompareUndefined(Expression* left,
650                                          Token::Value op,
651                                          Expression* right,
652                                          Expression** expr,
653                                          Isolate* isolate) {
654   if (IsVoidOfLiteral(left) && Token::IsEqualityOp(op)) {
655     *expr = right;
656     return true;
657   }
658   if (left->IsUndefinedLiteral(isolate) && Token::IsEqualityOp(op)) {
659     *expr = right;
660     return true;
661   }
662   return false;
663 }
664 
665 
IsLiteralCompareUndefined(Expression ** expr,Isolate * isolate)666 bool CompareOperation::IsLiteralCompareUndefined(
667     Expression** expr, Isolate* isolate) {
668   return MatchLiteralCompareUndefined(left_, op_, right_, expr, isolate) ||
669       MatchLiteralCompareUndefined(right_, op_, left_, expr, isolate);
670 }
671 
672 
673 // Check for the pattern: null equals <expression>
MatchLiteralCompareNull(Expression * left,Token::Value op,Expression * right,Expression ** expr)674 static bool MatchLiteralCompareNull(Expression* left,
675                                     Token::Value op,
676                                     Expression* right,
677                                     Expression** expr) {
678   if (left->IsNullLiteral() && Token::IsEqualityOp(op)) {
679     *expr = right;
680     return true;
681   }
682   return false;
683 }
684 
685 
IsLiteralCompareNull(Expression ** expr)686 bool CompareOperation::IsLiteralCompareNull(Expression** expr) {
687   return MatchLiteralCompareNull(left_, op_, right_, expr) ||
688       MatchLiteralCompareNull(right_, op_, left_, expr);
689 }
690 
691 
692 // ----------------------------------------------------------------------------
693 // Inlining support
694 
IsInlineable() const695 bool Declaration::IsInlineable() const {
696   return proxy()->var()->IsStackAllocated();
697 }
698 
IsInlineable() const699 bool FunctionDeclaration::IsInlineable() const {
700   return false;
701 }
702 
703 
704 // ----------------------------------------------------------------------------
705 // Recording of type feedback
706 
707 // TODO(rossberg): all RecordTypeFeedback functions should disappear
708 // once we use the common type field in the AST consistently.
709 
RecordToBooleanTypeFeedback(TypeFeedbackOracle * oracle)710 void Expression::RecordToBooleanTypeFeedback(TypeFeedbackOracle* oracle) {
711   set_to_boolean_types(oracle->ToBooleanTypes(test_id()));
712 }
713 
714 
IsUsingCallFeedbackICSlot(Isolate * isolate) const715 bool Call::IsUsingCallFeedbackICSlot(Isolate* isolate) const {
716   CallType call_type = GetCallType(isolate);
717   if (call_type == POSSIBLY_EVAL_CALL) {
718     return false;
719   }
720   return true;
721 }
722 
723 
IsUsingCallFeedbackSlot(Isolate * isolate) const724 bool Call::IsUsingCallFeedbackSlot(Isolate* isolate) const {
725   // SuperConstructorCall uses a CallConstructStub, which wants
726   // a Slot, in addition to any IC slots requested elsewhere.
727   return GetCallType(isolate) == SUPER_CALL;
728 }
729 
730 
AssignFeedbackVectorSlots(Isolate * isolate,FeedbackVectorSpec * spec,FeedbackVectorSlotCache * cache)731 void Call::AssignFeedbackVectorSlots(Isolate* isolate, FeedbackVectorSpec* spec,
732                                      FeedbackVectorSlotCache* cache) {
733   if (IsUsingCallFeedbackICSlot(isolate)) {
734     ic_slot_ = spec->AddCallICSlot();
735   }
736   if (IsUsingCallFeedbackSlot(isolate)) {
737     stub_slot_ = spec->AddGeneralSlot();
738   }
739 }
740 
741 
GetCallType(Isolate * isolate) const742 Call::CallType Call::GetCallType(Isolate* isolate) const {
743   VariableProxy* proxy = expression()->AsVariableProxy();
744   if (proxy != NULL) {
745     if (proxy->var()->is_possibly_eval(isolate)) {
746       return POSSIBLY_EVAL_CALL;
747     } else if (proxy->var()->IsUnallocatedOrGlobalSlot()) {
748       return GLOBAL_CALL;
749     } else if (proxy->var()->IsLookupSlot()) {
750       return LOOKUP_SLOT_CALL;
751     }
752   }
753 
754   if (expression()->IsSuperCallReference()) return SUPER_CALL;
755 
756   Property* property = expression()->AsProperty();
757   if (property != nullptr) {
758     bool is_super = property->IsSuperAccess();
759     if (property->key()->IsPropertyName()) {
760       return is_super ? NAMED_SUPER_PROPERTY_CALL : NAMED_PROPERTY_CALL;
761     } else {
762       return is_super ? KEYED_SUPER_PROPERTY_CALL : KEYED_PROPERTY_CALL;
763     }
764   }
765 
766   return OTHER_CALL;
767 }
768 
769 
770 // ----------------------------------------------------------------------------
771 // Implementation of AstVisitor
772 
VisitDeclarations(ZoneList<Declaration * > * declarations)773 void AstVisitor::VisitDeclarations(ZoneList<Declaration*>* declarations) {
774   for (int i = 0; i < declarations->length(); i++) {
775     Visit(declarations->at(i));
776   }
777 }
778 
779 
VisitStatements(ZoneList<Statement * > * statements)780 void AstVisitor::VisitStatements(ZoneList<Statement*>* statements) {
781   for (int i = 0; i < statements->length(); i++) {
782     Statement* stmt = statements->at(i);
783     Visit(stmt);
784     if (stmt->IsJump()) break;
785   }
786 }
787 
788 
VisitExpressions(ZoneList<Expression * > * expressions)789 void AstVisitor::VisitExpressions(ZoneList<Expression*>* expressions) {
790   for (int i = 0; i < expressions->length(); i++) {
791     // The variable statement visiting code may pass NULL expressions
792     // to this code. Maybe this should be handled by introducing an
793     // undefined expression or literal?  Revisit this code if this
794     // changes
795     Expression* expression = expressions->at(i);
796     if (expression != NULL) Visit(expression);
797   }
798 }
799 
800 
CaseClause(Zone * zone,Expression * label,ZoneList<Statement * > * statements,int pos)801 CaseClause::CaseClause(Zone* zone, Expression* label,
802                        ZoneList<Statement*>* statements, int pos)
803     : Expression(zone, pos),
804       label_(label),
805       statements_(statements),
806       compare_type_(Type::None(zone)) {}
807 
808 
Hash()809 uint32_t Literal::Hash() {
810   return raw_value()->IsString()
811              ? raw_value()->AsString()->hash()
812              : ComputeLongHash(double_to_uint64(raw_value()->AsNumber()));
813 }
814 
815 
816 // static
Match(void * literal1,void * literal2)817 bool Literal::Match(void* literal1, void* literal2) {
818   const AstValue* x = static_cast<Literal*>(literal1)->raw_value();
819   const AstValue* y = static_cast<Literal*>(literal2)->raw_value();
820   return (x->IsString() && y->IsString() && x->AsString() == y->AsString()) ||
821          (x->IsNumber() && y->IsNumber() && x->AsNumber() == y->AsNumber());
822 }
823 
824 
825 }  // namespace internal
826 }  // namespace v8
827