1 // Copyright 2011 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/parsing/func-name-inferrer.h"
6 
7 #include "src/ast/ast-value-factory.h"
8 #include "src/ast/ast.h"
9 #include "src/list-inl.h"
10 #include "src/objects-inl.h"
11 
12 namespace v8 {
13 namespace internal {
14 
FuncNameInferrer(AstValueFactory * ast_value_factory,Zone * zone)15 FuncNameInferrer::FuncNameInferrer(AstValueFactory* ast_value_factory,
16                                    Zone* zone)
17     : ast_value_factory_(ast_value_factory),
18       entries_stack_(10, zone),
19       names_stack_(5, zone),
20       funcs_to_infer_(4, zone),
21       zone_(zone) {
22 }
23 
24 
PushEnclosingName(const AstRawString * name)25 void FuncNameInferrer::PushEnclosingName(const AstRawString* name) {
26   // Enclosing name is a name of a constructor function. To check
27   // that it is really a constructor, we check that it is not empty
28   // and starts with a capital letter.
29   if (!name->IsEmpty() && unibrow::Uppercase::Is(name->FirstCharacter())) {
30     names_stack_.Add(Name(name, kEnclosingConstructorName), zone());
31   }
32 }
33 
34 
PushLiteralName(const AstRawString * name)35 void FuncNameInferrer::PushLiteralName(const AstRawString* name) {
36   if (IsOpen() && name != ast_value_factory_->prototype_string()) {
37     names_stack_.Add(Name(name, kLiteralName), zone());
38   }
39 }
40 
41 
PushVariableName(const AstRawString * name)42 void FuncNameInferrer::PushVariableName(const AstRawString* name) {
43   if (IsOpen() && name != ast_value_factory_->dot_result_string()) {
44     names_stack_.Add(Name(name, kVariableName), zone());
45   }
46 }
47 
RemoveAsyncKeywordFromEnd()48 void FuncNameInferrer::RemoveAsyncKeywordFromEnd() {
49   if (IsOpen()) {
50     CHECK(names_stack_.length() > 0);
51     CHECK(names_stack_.last().name->IsOneByteEqualTo("async"));
52     names_stack_.RemoveLast();
53   }
54 }
55 
MakeNameFromStack()56 const AstString* FuncNameInferrer::MakeNameFromStack() {
57   return MakeNameFromStackHelper(0, ast_value_factory_->empty_string());
58 }
59 
MakeNameFromStackHelper(int pos,const AstString * prev)60 const AstString* FuncNameInferrer::MakeNameFromStackHelper(
61     int pos, const AstString* prev) {
62   if (pos >= names_stack_.length()) return prev;
63   if (pos < names_stack_.length() - 1 &&
64       names_stack_.at(pos).type == kVariableName &&
65       names_stack_.at(pos + 1).type == kVariableName) {
66     // Skip consecutive variable declarations.
67     return MakeNameFromStackHelper(pos + 1, prev);
68   } else {
69     if (prev->length() > 0) {
70       const AstRawString* name = names_stack_.at(pos).name;
71       if (prev->length() + name->length() + 1 > String::kMaxLength) return prev;
72       const AstConsString* curr = ast_value_factory_->NewConsString(
73           ast_value_factory_->dot_string(), name);
74       curr = ast_value_factory_->NewConsString(prev, curr);
75       return MakeNameFromStackHelper(pos + 1, curr);
76     } else {
77       return MakeNameFromStackHelper(pos + 1, names_stack_.at(pos).name);
78     }
79   }
80 }
81 
82 
InferFunctionsNames()83 void FuncNameInferrer::InferFunctionsNames() {
84   const AstString* func_name = MakeNameFromStack();
85   for (int i = 0; i < funcs_to_infer_.length(); ++i) {
86     funcs_to_infer_[i]->set_raw_inferred_name(func_name);
87   }
88   funcs_to_infer_.Rewind(0);
89 }
90 
91 
92 }  // namespace internal
93 }  // namespace v8
94