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