1 //===- Synthesis.cpp ------------------------------------------*- C++ -*-=====//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 #include "clang/Basic/TokenKinds.h"
9 #include "clang/Tooling/Syntax/BuildTree.h"
10 #include "clang/Tooling/Syntax/Tree.h"
11 
12 using namespace clang;
13 
14 /// Exposes private syntax tree APIs required to implement node synthesis.
15 /// Should not be used for anything else.
16 class clang::syntax::FactoryImpl {
17 public:
18   static void setCanModify(syntax::Node *N) { N->CanModify = true; }
19 
20   static void prependChildLowLevel(syntax::Tree *T, syntax::Node *Child,
21                                    syntax::NodeRole R) {
22     T->prependChildLowLevel(Child, R);
23   }
24 
25   static std::pair<FileID, ArrayRef<Token>>
26   lexBuffer(syntax::Arena &A, std::unique_ptr<llvm::MemoryBuffer> Buffer) {
27     return A.lexBuffer(std::move(Buffer));
28   }
29 };
30 
31 syntax::Leaf *clang::syntax::createLeaf(syntax::Arena &A, tok::TokenKind K,
32                                         StringRef Spelling) {
33   auto Tokens =
34       FactoryImpl::lexBuffer(A, llvm::MemoryBuffer::getMemBuffer(Spelling))
35           .second;
36   assert(Tokens.size() == 1);
37   assert(Tokens.front().kind() == K &&
38          "spelling is not lexed into the expected kind of token");
39 
40   auto *Leaf = new (A.getAllocator()) syntax::Leaf(Tokens.begin());
41   syntax::FactoryImpl::setCanModify(Leaf);
42   Leaf->assertInvariants();
43   return Leaf;
44 }
45 
46 syntax::Leaf *clang::syntax::createLeaf(syntax::Arena &A, tok::TokenKind K) {
47   const auto *Spelling = tok::getPunctuatorSpelling(K);
48   if (!Spelling)
49     Spelling = tok::getKeywordSpelling(K);
50   assert(Spelling &&
51          "Cannot infer the spelling of the token from its token kind.");
52   return createLeaf(A, K, Spelling);
53 }
54 
55 namespace {
56 // Allocates the concrete syntax `Tree` according to its `NodeKind`.
57 syntax::Tree *allocateTree(syntax::Arena &A, syntax::NodeKind Kind) {
58   switch (Kind) {
59   case syntax::NodeKind::Leaf:
60     assert(false);
61     break;
62   case syntax::NodeKind::TranslationUnit:
63     return new (A.getAllocator()) syntax::TranslationUnit;
64   case syntax::NodeKind::UnknownExpression:
65     return new (A.getAllocator()) syntax::UnknownExpression;
66   case syntax::NodeKind::ParenExpression:
67     return new (A.getAllocator()) syntax::ParenExpression;
68   case syntax::NodeKind::ThisExpression:
69     return new (A.getAllocator()) syntax::ThisExpression;
70   case syntax::NodeKind::IntegerLiteralExpression:
71     return new (A.getAllocator()) syntax::IntegerLiteralExpression;
72   case syntax::NodeKind::CharacterLiteralExpression:
73     return new (A.getAllocator()) syntax::CharacterLiteralExpression;
74   case syntax::NodeKind::FloatingLiteralExpression:
75     return new (A.getAllocator()) syntax::FloatingLiteralExpression;
76   case syntax::NodeKind::StringLiteralExpression:
77     return new (A.getAllocator()) syntax::StringLiteralExpression;
78   case syntax::NodeKind::BoolLiteralExpression:
79     return new (A.getAllocator()) syntax::BoolLiteralExpression;
80   case syntax::NodeKind::CxxNullPtrExpression:
81     return new (A.getAllocator()) syntax::CxxNullPtrExpression;
82   case syntax::NodeKind::IntegerUserDefinedLiteralExpression:
83     return new (A.getAllocator()) syntax::IntegerUserDefinedLiteralExpression;
84   case syntax::NodeKind::FloatUserDefinedLiteralExpression:
85     return new (A.getAllocator()) syntax::FloatUserDefinedLiteralExpression;
86   case syntax::NodeKind::CharUserDefinedLiteralExpression:
87     return new (A.getAllocator()) syntax::CharUserDefinedLiteralExpression;
88   case syntax::NodeKind::StringUserDefinedLiteralExpression:
89     return new (A.getAllocator()) syntax::StringUserDefinedLiteralExpression;
90   case syntax::NodeKind::PrefixUnaryOperatorExpression:
91     return new (A.getAllocator()) syntax::PrefixUnaryOperatorExpression;
92   case syntax::NodeKind::PostfixUnaryOperatorExpression:
93     return new (A.getAllocator()) syntax::PostfixUnaryOperatorExpression;
94   case syntax::NodeKind::BinaryOperatorExpression:
95     return new (A.getAllocator()) syntax::BinaryOperatorExpression;
96   case syntax::NodeKind::UnqualifiedId:
97     return new (A.getAllocator()) syntax::UnqualifiedId;
98   case syntax::NodeKind::IdExpression:
99     return new (A.getAllocator()) syntax::IdExpression;
100   case syntax::NodeKind::CallExpression:
101     return new (A.getAllocator()) syntax::CallExpression;
102   case syntax::NodeKind::UnknownStatement:
103     return new (A.getAllocator()) syntax::UnknownStatement;
104   case syntax::NodeKind::DeclarationStatement:
105     return new (A.getAllocator()) syntax::DeclarationStatement;
106   case syntax::NodeKind::EmptyStatement:
107     return new (A.getAllocator()) syntax::EmptyStatement;
108   case syntax::NodeKind::SwitchStatement:
109     return new (A.getAllocator()) syntax::SwitchStatement;
110   case syntax::NodeKind::CaseStatement:
111     return new (A.getAllocator()) syntax::CaseStatement;
112   case syntax::NodeKind::DefaultStatement:
113     return new (A.getAllocator()) syntax::DefaultStatement;
114   case syntax::NodeKind::IfStatement:
115     return new (A.getAllocator()) syntax::IfStatement;
116   case syntax::NodeKind::ForStatement:
117     return new (A.getAllocator()) syntax::ForStatement;
118   case syntax::NodeKind::WhileStatement:
119     return new (A.getAllocator()) syntax::WhileStatement;
120   case syntax::NodeKind::ContinueStatement:
121     return new (A.getAllocator()) syntax::ContinueStatement;
122   case syntax::NodeKind::BreakStatement:
123     return new (A.getAllocator()) syntax::BreakStatement;
124   case syntax::NodeKind::ReturnStatement:
125     return new (A.getAllocator()) syntax::ReturnStatement;
126   case syntax::NodeKind::RangeBasedForStatement:
127     return new (A.getAllocator()) syntax::RangeBasedForStatement;
128   case syntax::NodeKind::ExpressionStatement:
129     return new (A.getAllocator()) syntax::ExpressionStatement;
130   case syntax::NodeKind::CompoundStatement:
131     return new (A.getAllocator()) syntax::CompoundStatement;
132   case syntax::NodeKind::UnknownDeclaration:
133     return new (A.getAllocator()) syntax::UnknownDeclaration;
134   case syntax::NodeKind::EmptyDeclaration:
135     return new (A.getAllocator()) syntax::EmptyDeclaration;
136   case syntax::NodeKind::StaticAssertDeclaration:
137     return new (A.getAllocator()) syntax::StaticAssertDeclaration;
138   case syntax::NodeKind::LinkageSpecificationDeclaration:
139     return new (A.getAllocator()) syntax::LinkageSpecificationDeclaration;
140   case syntax::NodeKind::SimpleDeclaration:
141     return new (A.getAllocator()) syntax::SimpleDeclaration;
142   case syntax::NodeKind::TemplateDeclaration:
143     return new (A.getAllocator()) syntax::TemplateDeclaration;
144   case syntax::NodeKind::ExplicitTemplateInstantiation:
145     return new (A.getAllocator()) syntax::ExplicitTemplateInstantiation;
146   case syntax::NodeKind::NamespaceDefinition:
147     return new (A.getAllocator()) syntax::NamespaceDefinition;
148   case syntax::NodeKind::NamespaceAliasDefinition:
149     return new (A.getAllocator()) syntax::NamespaceAliasDefinition;
150   case syntax::NodeKind::UsingNamespaceDirective:
151     return new (A.getAllocator()) syntax::UsingNamespaceDirective;
152   case syntax::NodeKind::UsingDeclaration:
153     return new (A.getAllocator()) syntax::UsingDeclaration;
154   case syntax::NodeKind::TypeAliasDeclaration:
155     return new (A.getAllocator()) syntax::TypeAliasDeclaration;
156   case syntax::NodeKind::SimpleDeclarator:
157     return new (A.getAllocator()) syntax::SimpleDeclarator;
158   case syntax::NodeKind::ParenDeclarator:
159     return new (A.getAllocator()) syntax::ParenDeclarator;
160   case syntax::NodeKind::ArraySubscript:
161     return new (A.getAllocator()) syntax::ArraySubscript;
162   case syntax::NodeKind::TrailingReturnType:
163     return new (A.getAllocator()) syntax::TrailingReturnType;
164   case syntax::NodeKind::ParametersAndQualifiers:
165     return new (A.getAllocator()) syntax::ParametersAndQualifiers;
166   case syntax::NodeKind::MemberPointer:
167     return new (A.getAllocator()) syntax::MemberPointer;
168   case syntax::NodeKind::GlobalNameSpecifier:
169     return new (A.getAllocator()) syntax::GlobalNameSpecifier;
170   case syntax::NodeKind::DecltypeNameSpecifier:
171     return new (A.getAllocator()) syntax::DecltypeNameSpecifier;
172   case syntax::NodeKind::IdentifierNameSpecifier:
173     return new (A.getAllocator()) syntax::IdentifierNameSpecifier;
174   case syntax::NodeKind::SimpleTemplateNameSpecifier:
175     return new (A.getAllocator()) syntax::SimpleTemplateNameSpecifier;
176   case syntax::NodeKind::NestedNameSpecifier:
177     return new (A.getAllocator()) syntax::NestedNameSpecifier;
178   case syntax::NodeKind::MemberExpression:
179     return new (A.getAllocator()) syntax::MemberExpression;
180   case syntax::NodeKind::CallArguments:
181     return new (A.getAllocator()) syntax::CallArguments;
182   case syntax::NodeKind::ParameterDeclarationList:
183     return new (A.getAllocator()) syntax::ParameterDeclarationList;
184   }
185   llvm_unreachable("unknown node kind");
186 }
187 } // namespace
188 
189 syntax::Tree *clang::syntax::createTree(
190     syntax::Arena &A,
191     std::vector<std::pair<syntax::Node *, syntax::NodeRole>> Children,
192     syntax::NodeKind K) {
193   auto *T = allocateTree(A, K);
194   FactoryImpl::setCanModify(T);
195   for (auto ChildIt = Children.rbegin(); ChildIt != Children.rend();
196        std::advance(ChildIt, 1))
197     FactoryImpl::prependChildLowLevel(T, ChildIt->first, ChildIt->second);
198 
199   T->assertInvariants();
200   return T;
201 }
202 
203 syntax::EmptyStatement *clang::syntax::createEmptyStatement(syntax::Arena &A) {
204   return cast<EmptyStatement>(
205       createTree(A, {{createLeaf(A, tok::semi), NodeRole::Unknown}},
206                  NodeKind::EmptyStatement));
207 }
208