1 // Copyright (C) 2020-2023 Free Software Foundation, Inc.
2
3 // This file is part of GCC.
4
5 // GCC is free software; you can redistribute it and/or modify it under
6 // the terms of the GNU General Public License as published by the Free
7 // Software Foundation; either version 3, or (at your option) any later
8 // version.
9
10 // GCC is distributed in the hope that it will be useful, but WITHOUT ANY
11 // WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 // FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
13 // for more details.
14
15 // You should have received a copy of the GNU General Public License
16 // along with GCC; see the file COPYING3. If not see
17 // <http://www.gnu.org/licenses/>.
18
19 #include "rust-ast-visitor.h"
20 #include "rust-ast.h"
21 #include "rust-macro-expand.h"
22
23 namespace Rust {
24 // Visitor used to expand attributes.
25 class AttrVisitor : public AST::ASTVisitor
26 {
27 private:
28 MacroExpander &expander;
29 void maybe_expand_expr (std::unique_ptr<AST::Expr> &expr);
30 void maybe_expand_type (std::unique_ptr<AST::Type> &expr);
31
32 public:
33 AttrVisitor (MacroExpander &expander) : expander (expander) {}
34
35 void expand_struct_fields (std::vector<AST::StructField> &fields);
36 void expand_tuple_fields (std::vector<AST::TupleField> &fields);
37 void expand_function_params (std::vector<AST::FunctionParam> ¶ms);
38 void expand_generic_args (AST::GenericArgs &args);
39 void expand_qualified_path_type (AST::QualifiedPathType &path_type);
40 void expand_closure_params (std::vector<AST::ClosureParam> ¶ms);
41 void expand_self_param (AST::SelfParam &self_param);
42 void expand_where_clause (AST::WhereClause &where_clause);
43 void expand_trait_function_decl (AST::TraitFunctionDecl &decl);
44 void expand_trait_method_decl (AST::TraitMethodDecl &decl);
45
46 /**
47 * Expand a set of values, erasing them if they are marked for strip, and
48 * replacing them with expanded macro nodes if necessary.
49 * This function is slightly different from `expand_pointer_allow_strip` as
50 * it can only be called in certain expansion contexts - where macro
51 * invocations are allowed.
52 *
53 * @param ctx Context to use for macro expansion
54 * @param values Iterable reference over values to replace or erase
55 * @param extractor Function to call when replacing values with the content
56 * of an expanded AST node
57 */
58 template <typename T, typename U>
59 void expand_macro_children (MacroExpander::ContextType ctx, T &values,
60 std::function<U (AST::SingleASTNode)> extractor)
61 {
62 expander.push_context (ctx);
63
64 for (auto it = values.begin (); it != values.end ();)
65 {
66 auto &value = *it;
67
68 // mark for stripping if required
69 value->accept_vis (*this);
70
71 auto final_fragment = expander.take_expanded_fragment ();
72
73 if (final_fragment.should_expand ())
74 {
75 it = values.erase (it);
76 for (auto &node : final_fragment.get_nodes ())
77 {
78 auto new_node = extractor (node);
79 if (new_node != nullptr && !new_node->is_marked_for_strip ())
80 {
81 it = values.insert (it, std::move (new_node));
82 it++;
83 }
84 }
85 }
86 else if (value->is_marked_for_strip ())
87 {
88 it = values.erase (it);
89 }
90 else
91 {
92 ++it;
93 }
94 }
95
96 expander.pop_context ();
97 }
98
99 template <typename T> void expand_pointer_allow_strip (T &values)
100 {
101 for (auto it = values.begin (); it != values.end ();)
102 {
103 auto &value = *it;
104
105 // mark for stripping if required
106 value->accept_vis (*this);
107 if (value->is_marked_for_strip ())
108 {
109 it = values.erase (it);
110 }
111 else
112 {
113 ++it;
114 }
115 }
116 }
117
118 void visit (AST::Token &) override;
119 void visit (AST::DelimTokenTree &) override;
120 void visit (AST::AttrInputMetaItemContainer &) override;
121 void visit (AST::IdentifierExpr &ident_expr) override;
122 void visit (AST::Lifetime &) override;
123 void visit (AST::LifetimeParam &) override;
124 void visit (AST::ConstGenericParam &) override;
125
126 void visit (AST::MacroInvocation ¯o_invoc) override;
127
128 void visit (AST::PathInExpression &path) override;
129 void visit (AST::TypePathSegment &) override;
130 void visit (AST::TypePathSegmentGeneric &segment) override;
131 void visit (AST::TypePathSegmentFunction &segment) override;
132 void visit (AST::TypePath &path) override;
133 void visit (AST::QualifiedPathInExpression &path) override;
134 void visit (AST::QualifiedPathInType &path) override;
135
136 void visit (AST::LiteralExpr &expr) override;
137 void visit (AST::AttrInputLiteral &) override;
138 void visit (AST::MetaItemLitExpr &) override;
139 void visit (AST::MetaItemPathLit &) override;
140 void visit (AST::BorrowExpr &expr) override;
141 void visit (AST::DereferenceExpr &expr) override;
142 void visit (AST::ErrorPropagationExpr &expr) override;
143 void visit (AST::NegationExpr &expr) override;
144 void visit (AST::ArithmeticOrLogicalExpr &expr) override;
145 void visit (AST::ComparisonExpr &expr) override;
146 void visit (AST::LazyBooleanExpr &expr) override;
147 void visit (AST::TypeCastExpr &expr) override;
148 void visit (AST::AssignmentExpr &expr) override;
149 void visit (AST::CompoundAssignmentExpr &expr) override;
150 void visit (AST::GroupedExpr &expr) override;
151 void visit (AST::ArrayElemsValues &elems) override;
152 void visit (AST::ArrayElemsCopied &elems) override;
153 void visit (AST::ArrayExpr &expr) override;
154 void visit (AST::ArrayIndexExpr &expr) override;
155 void visit (AST::TupleExpr &expr) override;
156 void visit (AST::TupleIndexExpr &expr) override;
157 void visit (AST::StructExprStruct &expr) override;
158 void visit (AST::StructExprFieldIdentifier &) override;
159 void visit (AST::StructExprFieldIdentifierValue &field) override;
160
161 void visit (AST::StructExprFieldIndexValue &field) override;
162 void visit (AST::StructExprStructFields &expr) override;
163 void visit (AST::StructExprStructBase &expr) override;
164 void visit (AST::CallExpr &expr) override;
165 void visit (AST::MethodCallExpr &expr) override;
166 void visit (AST::FieldAccessExpr &expr) override;
167 void visit (AST::ClosureExprInner &expr) override;
168
169 void visit (AST::BlockExpr &expr) override;
170
171 void visit (AST::ClosureExprInnerTyped &expr) override;
172 void visit (AST::ContinueExpr &expr) override;
173 void visit (AST::BreakExpr &expr) override;
174 void visit (AST::RangeFromToExpr &expr) override;
175 void visit (AST::RangeFromExpr &expr) override;
176 void visit (AST::RangeToExpr &expr) override;
177 void visit (AST::RangeFullExpr &) override;
178 void visit (AST::RangeFromToInclExpr &expr) override;
179 void visit (AST::RangeToInclExpr &expr) override;
180 void visit (AST::ReturnExpr &expr) override;
181 void visit (AST::UnsafeBlockExpr &expr) override;
182 void visit (AST::LoopExpr &expr) override;
183 void visit (AST::WhileLoopExpr &expr) override;
184 void visit (AST::WhileLetLoopExpr &expr) override;
185 void visit (AST::ForLoopExpr &expr) override;
186 void visit (AST::IfExpr &expr) override;
187 void visit (AST::IfExprConseqElse &expr) override;
188 void visit (AST::IfExprConseqIf &expr) override;
189 void visit (AST::IfExprConseqIfLet &expr) override;
190 void visit (AST::IfLetExpr &expr) override;
191 void visit (AST::IfLetExprConseqElse &expr) override;
192 void visit (AST::IfLetExprConseqIf &expr) override;
193 void visit (AST::IfLetExprConseqIfLet &expr) override;
194 void visit (AST::MatchExpr &expr) override;
195 void visit (AST::AwaitExpr &expr) override;
196 void visit (AST::AsyncBlockExpr &expr) override;
197 void visit (AST::TypeParam ¶m) override;
198 void visit (AST::LifetimeWhereClauseItem &) override;
199 void visit (AST::TypeBoundWhereClauseItem &item) override;
200 void visit (AST::Method &method) override;
201 void visit (AST::Module &module) override;
202 void visit (AST::ExternCrate &crate) override;
203 void visit (AST::UseTreeGlob &) override;
204 void visit (AST::UseTreeList &) override;
205 void visit (AST::UseTreeRebind &) override;
206 void visit (AST::UseDeclaration &use_decl) override;
207 void visit (AST::Function &function) override;
208 void visit (AST::TypeAlias &type_alias) override;
209 void visit (AST::StructStruct &struct_item) override;
210 void visit (AST::TupleStruct &tuple_struct) override;
211 void visit (AST::EnumItem &item) override;
212 void visit (AST::EnumItemTuple &item) override;
213 void visit (AST::EnumItemStruct &item) override;
214 void visit (AST::EnumItemDiscriminant &item) override;
215 void visit (AST::Enum &enum_item) override;
216 void visit (AST::Union &union_item) override;
217 void visit (AST::ConstantItem &const_item) override;
218 void visit (AST::StaticItem &static_item) override;
219 void visit (AST::TraitItemFunc &item) override;
220 void visit (AST::TraitItemMethod &item) override;
221 void visit (AST::TraitItemConst &item) override;
222 void visit (AST::TraitItemType &item) override;
223 void visit (AST::Trait &trait) override;
224 void visit (AST::InherentImpl &impl) override;
225 void visit (AST::TraitImpl &impl) override;
226 void visit (AST::ExternalStaticItem &item) override;
227 void visit (AST::ExternalFunctionItem &item) override;
228 void visit (AST::ExternBlock &block) override;
229
230 // I don't think it would be possible to strip macros without expansion
231 void visit (AST::MacroMatchFragment &) override;
232 void visit (AST::MacroMatchRepetition &) override;
233 void visit (AST::MacroMatcher &) override;
234 void visit (AST::MacroRulesDefinition &rules_def) override;
235 void visit (AST::MetaItemPath &) override;
236 void visit (AST::MetaItemSeq &) override;
237 void visit (AST::MetaWord &) override;
238 void visit (AST::MetaNameValueStr &) override;
239 void visit (AST::MetaListPaths &) override;
240 void visit (AST::MetaListNameValueStr &) override;
241 void visit (AST::LiteralPattern &) override;
242 void visit (AST::IdentifierPattern &pattern) override;
243 void visit (AST::WildcardPattern &) override;
244 void visit (AST::RangePatternBoundLiteral &) override;
245 void visit (AST::RangePatternBoundPath &bound) override;
246 void visit (AST::RangePatternBoundQualPath &bound) override;
247 void visit (AST::RangePattern &pattern) override;
248 void visit (AST::ReferencePattern &pattern) override;
249 void visit (AST::StructPatternFieldTuplePat &field) override;
250 void visit (AST::StructPatternFieldIdentPat &field) override;
251 void visit (AST::StructPatternFieldIdent &field) override;
252 void visit (AST::StructPattern &pattern) override;
253 void visit (AST::TupleStructItemsNoRange &tuple_items) override;
254 void visit (AST::TupleStructItemsRange &tuple_items) override;
255 void visit (AST::TupleStructPattern &pattern) override;
256 void visit (AST::TuplePatternItemsMultiple &tuple_items) override;
257 void visit (AST::TuplePatternItemsRanged &tuple_items) override;
258 void visit (AST::TuplePattern &pattern) override;
259 void visit (AST::GroupedPattern &pattern) override;
260 void visit (AST::SlicePattern &pattern) override;
261 void visit (AST::AltPattern &pattern) override;
262
263 void visit (AST::EmptyStmt &) override;
264 void visit (AST::LetStmt &stmt) override;
265 void visit (AST::ExprStmtWithoutBlock &stmt) override;
266 void visit (AST::ExprStmtWithBlock &stmt) override;
267
268 void visit (AST::TraitBound &bound) override;
269 void visit (AST::ImplTraitType &type) override;
270 void visit (AST::TraitObjectType &type) override;
271 void visit (AST::ParenthesisedType &type) override;
272 void visit (AST::ImplTraitTypeOneBound &type) override;
273 void visit (AST::TraitObjectTypeOneBound &type) override;
274 void visit (AST::TupleType &type) override;
275 void visit (AST::NeverType &) override;
276 void visit (AST::RawPointerType &type) override;
277 void visit (AST::ReferenceType &type) override;
278 void visit (AST::ArrayType &type) override;
279 void visit (AST::SliceType &type) override;
280 void visit (AST::InferredType &) override;
281 void visit (AST::BareFunctionType &type) override;
282 };
283 } // namespace Rust