1 | //===--- Designator.h - Initialization Designator ---------------*- 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 | // |
9 | // This file defines interfaces used to represent designators (a la |
10 | // C99 designated initializers) during parsing. |
11 | // |
12 | //===----------------------------------------------------------------------===// |
13 | |
14 | #ifndef LLVM_CLANG_SEMA_DESIGNATOR_H |
15 | #define LLVM_CLANG_SEMA_DESIGNATOR_H |
16 | |
17 | #include "clang/Basic/SourceLocation.h" |
18 | #include "llvm/ADT/SmallVector.h" |
19 | |
20 | namespace clang { |
21 | |
22 | class Expr; |
23 | class IdentifierInfo; |
24 | |
25 | /// Designator - A designator in a C99 designated initializer. |
26 | /// |
27 | /// This class is a discriminated union which holds the various |
28 | /// different sorts of designators possible. A Designation is an array of |
29 | /// these. An example of a designator are things like this: |
30 | /// |
31 | /// [8] .field [47] // C99 designation: 3 designators |
32 | /// [8 ... 47] field: // GNU extensions: 2 designators |
33 | /// |
34 | /// These occur in initializers, e.g.: |
35 | /// |
36 | /// int a[10] = {2, 4, [8]=9, 10}; |
37 | /// |
38 | class Designator { |
39 | /// A field designator, e.g., ".x = 42". |
40 | struct FieldDesignatorInfo { |
41 | /// Refers to the field being initialized. |
42 | const IdentifierInfo *FieldName; |
43 | |
44 | /// The location of the '.' in the designated initializer. |
45 | SourceLocation DotLoc; |
46 | |
47 | /// The location of the field name in the designated initializer. |
48 | SourceLocation FieldLoc; |
49 | |
50 | FieldDesignatorInfo(const IdentifierInfo *FieldName, SourceLocation DotLoc, |
51 | SourceLocation FieldLoc) |
52 | : FieldName(FieldName), DotLoc(DotLoc), FieldLoc(FieldLoc) {} |
53 | }; |
54 | |
55 | /// An array designator, e.g., "[42] = 0". |
56 | struct ArrayDesignatorInfo { |
57 | Expr *Index; |
58 | |
59 | // The location of the '[' in the designated initializer. |
60 | SourceLocation LBracketLoc; |
61 | |
62 | // The location of the ']' in the designated initializer. |
63 | mutable SourceLocation RBracketLoc; |
64 | |
65 | ArrayDesignatorInfo(Expr *Index, SourceLocation LBracketLoc) |
66 | : Index(Index), LBracketLoc(LBracketLoc) {} |
67 | }; |
68 | |
69 | /// An array range designator, e.g. "[42 ... 50] = 1". |
70 | struct ArrayRangeDesignatorInfo { |
71 | Expr *Start; |
72 | Expr *End; |
73 | |
74 | // The location of the '[' in the designated initializer. |
75 | SourceLocation LBracketLoc; |
76 | |
77 | // The location of the '...' in the designated initializer. |
78 | SourceLocation EllipsisLoc; |
79 | |
80 | // The location of the ']' in the designated initializer. |
81 | mutable SourceLocation RBracketLoc; |
82 | |
83 | ArrayRangeDesignatorInfo(Expr *Start, Expr *End, SourceLocation LBracketLoc, |
84 | SourceLocation EllipsisLoc) |
85 | : Start(Start), End(End), LBracketLoc(LBracketLoc), |
86 | EllipsisLoc(EllipsisLoc) {} |
87 | }; |
88 | |
89 | /// The kind of designator this describes. |
90 | enum DesignatorKind { |
91 | FieldDesignator, |
92 | ArrayDesignator, |
93 | ArrayRangeDesignator |
94 | }; |
95 | |
96 | DesignatorKind Kind; |
97 | |
98 | union { |
99 | FieldDesignatorInfo FieldInfo; |
100 | ArrayDesignatorInfo ArrayInfo; |
101 | ArrayRangeDesignatorInfo ArrayRangeInfo; |
102 | }; |
103 | |
104 | Designator(DesignatorKind Kind) : Kind(Kind) {} |
105 | |
106 | public: |
107 | bool isFieldDesignator() const { return Kind == FieldDesignator; } |
108 | bool isArrayDesignator() const { return Kind == ArrayDesignator; } |
109 | bool isArrayRangeDesignator() const { return Kind == ArrayRangeDesignator; } |
110 | |
111 | //===--------------------------------------------------------------------===// |
112 | // FieldDesignatorInfo |
113 | |
114 | /// Creates a field designator. |
115 | static Designator CreateFieldDesignator(const IdentifierInfo *FieldName, |
116 | SourceLocation DotLoc, |
117 | SourceLocation FieldLoc) { |
118 | Designator D(FieldDesignator); |
119 | new (&D.FieldInfo) FieldDesignatorInfo(FieldName, DotLoc, FieldLoc); |
120 | return D; |
121 | } |
122 | |
123 | const IdentifierInfo *getFieldDecl() const { |
124 | assert(isFieldDesignator() && "Invalid accessor" ); |
125 | return FieldInfo.FieldName; |
126 | } |
127 | |
128 | SourceLocation getDotLoc() const { |
129 | assert(isFieldDesignator() && "Invalid accessor" ); |
130 | return FieldInfo.DotLoc; |
131 | } |
132 | |
133 | SourceLocation getFieldLoc() const { |
134 | assert(isFieldDesignator() && "Invalid accessor" ); |
135 | return FieldInfo.FieldLoc; |
136 | } |
137 | |
138 | //===--------------------------------------------------------------------===// |
139 | // ArrayDesignatorInfo: |
140 | |
141 | /// Creates an array designator. |
142 | static Designator CreateArrayDesignator(Expr *Index, |
143 | SourceLocation LBracketLoc) { |
144 | Designator D(ArrayDesignator); |
145 | new (&D.ArrayInfo) ArrayDesignatorInfo(Index, LBracketLoc); |
146 | return D; |
147 | } |
148 | |
149 | Expr *getArrayIndex() const { |
150 | assert(isArrayDesignator() && "Invalid accessor" ); |
151 | return ArrayInfo.Index; |
152 | } |
153 | |
154 | SourceLocation getLBracketLoc() const { |
155 | assert((isArrayDesignator() || isArrayRangeDesignator()) && |
156 | "Invalid accessor" ); |
157 | return isArrayDesignator() ? ArrayInfo.LBracketLoc |
158 | : ArrayRangeInfo.LBracketLoc; |
159 | } |
160 | |
161 | SourceLocation getRBracketLoc() const { |
162 | assert((isArrayDesignator() || isArrayRangeDesignator()) && |
163 | "Invalid accessor" ); |
164 | return isArrayDesignator() ? ArrayInfo.RBracketLoc |
165 | : ArrayRangeInfo.RBracketLoc; |
166 | } |
167 | |
168 | //===--------------------------------------------------------------------===// |
169 | // ArrayRangeDesignatorInfo: |
170 | |
171 | /// Creates a GNU array-range designator. |
172 | static Designator CreateArrayRangeDesignator(Expr *Start, Expr *End, |
173 | SourceLocation LBracketLoc, |
174 | SourceLocation EllipsisLoc) { |
175 | Designator D(ArrayRangeDesignator); |
176 | new (&D.ArrayRangeInfo) |
177 | ArrayRangeDesignatorInfo(Start, End, LBracketLoc, EllipsisLoc); |
178 | return D; |
179 | } |
180 | |
181 | Expr *getArrayRangeStart() const { |
182 | assert(isArrayRangeDesignator() && "Invalid accessor" ); |
183 | return ArrayRangeInfo.Start; |
184 | } |
185 | |
186 | Expr *getArrayRangeEnd() const { |
187 | assert(isArrayRangeDesignator() && "Invalid accessor" ); |
188 | return ArrayRangeInfo.End; |
189 | } |
190 | |
191 | SourceLocation getEllipsisLoc() const { |
192 | assert(isArrayRangeDesignator() && "Invalid accessor" ); |
193 | return ArrayRangeInfo.EllipsisLoc; |
194 | } |
195 | |
196 | void setRBracketLoc(SourceLocation RBracketLoc) const { |
197 | assert((isArrayDesignator() || isArrayRangeDesignator()) && |
198 | "Invalid accessor" ); |
199 | if (isArrayDesignator()) |
200 | ArrayInfo.RBracketLoc = RBracketLoc; |
201 | else |
202 | ArrayRangeInfo.RBracketLoc = RBracketLoc; |
203 | } |
204 | }; |
205 | |
206 | /// Designation - Represent a full designation, which is a sequence of |
207 | /// designators. This class is mostly a helper for InitListDesignations. |
208 | class Designation { |
209 | /// Designators - The actual designators for this initializer. |
210 | SmallVector<Designator, 2> Designators; |
211 | |
212 | public: |
213 | /// AddDesignator - Add a designator to the end of this list. |
214 | void AddDesignator(Designator D) { Designators.push_back(Elt: D); } |
215 | |
216 | bool empty() const { return Designators.empty(); } |
217 | |
218 | unsigned getNumDesignators() const { return Designators.size(); } |
219 | const Designator &getDesignator(unsigned Idx) const { |
220 | assert(Idx < Designators.size()); |
221 | return Designators[Idx]; |
222 | } |
223 | }; |
224 | |
225 | } // end namespace clang |
226 | |
227 | #endif |
228 | |