1 | //===- PredicateTree.h - Predicate tree node definitions --------*- 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 contains definitions for nodes of a tree structure for representing |
10 | // the general control flow within a pattern match. |
11 | // |
12 | //===----------------------------------------------------------------------===// |
13 | |
14 | #ifndef MLIR_LIB_CONVERSION_PDLTOPDLINTERP_PREDICATETREE_H_ |
15 | #define MLIR_LIB_CONVERSION_PDLTOPDLINTERP_PREDICATETREE_H_ |
16 | |
17 | #include "Predicate.h" |
18 | #include "mlir/Dialect/PDL/IR/PDLOps.h" |
19 | #include "llvm/ADT/MapVector.h" |
20 | |
21 | namespace mlir { |
22 | class ModuleOp; |
23 | |
24 | namespace pdl_to_pdl_interp { |
25 | |
26 | class MatcherNode; |
27 | |
28 | /// A PositionalPredicate is a predicate that is associated with a specific |
29 | /// positional value. |
30 | struct PositionalPredicate { |
31 | PositionalPredicate(Position *pos, |
32 | const PredicateBuilder::Predicate &predicate) |
33 | : position(pos), question(predicate.first), answer(predicate.second) {} |
34 | |
35 | /// The position the predicate is applied to. |
36 | Position *position; |
37 | |
38 | /// The question that the predicate applies. |
39 | Qualifier *question; |
40 | |
41 | /// The expected answer of the predicate. |
42 | Qualifier *answer; |
43 | }; |
44 | |
45 | //===----------------------------------------------------------------------===// |
46 | // MatcherNode |
47 | //===----------------------------------------------------------------------===// |
48 | |
49 | /// This class represents the base of a predicate matcher node. |
50 | class MatcherNode { |
51 | public: |
52 | virtual ~MatcherNode() = default; |
53 | |
54 | /// Given a module containing PDL pattern operations, generate a matcher tree |
55 | /// using the patterns within the given module and return the root matcher |
56 | /// node. `valueToPosition` is a map that is populated with the original |
57 | /// pdl values and their corresponding positions in the matcher tree. |
58 | static std::unique_ptr<MatcherNode> |
59 | generateMatcherTree(ModuleOp module, PredicateBuilder &builder, |
60 | DenseMap<Value, Position *> &valueToPosition); |
61 | |
62 | /// Returns the position on which the question predicate should be checked. |
63 | Position *getPosition() const { return position; } |
64 | |
65 | /// Returns the predicate checked on this node. |
66 | Qualifier *getQuestion() const { return question; } |
67 | |
68 | /// Returns the node that should be visited if this, or a subsequent node |
69 | /// fails. |
70 | std::unique_ptr<MatcherNode> &getFailureNode() { return failureNode; } |
71 | |
72 | /// Sets the node that should be visited if this, or a subsequent node fails. |
73 | void setFailureNode(std::unique_ptr<MatcherNode> node) { |
74 | failureNode = std::move(node); |
75 | } |
76 | |
77 | /// Returns the unique type ID of this matcher instance. This should not be |
78 | /// used directly, and is provided to support type casting. |
79 | TypeID getMatcherTypeID() const { return matcherTypeID; } |
80 | |
81 | protected: |
82 | MatcherNode(TypeID matcherTypeID, Position *position = nullptr, |
83 | Qualifier *question = nullptr, |
84 | std::unique_ptr<MatcherNode> failureNode = nullptr); |
85 | |
86 | private: |
87 | /// The position on which the predicate should be checked. |
88 | Position *position; |
89 | |
90 | /// The predicate that is checked on the given position. |
91 | Qualifier *question; |
92 | |
93 | /// The node to visit if this node fails. |
94 | std::unique_ptr<MatcherNode> failureNode; |
95 | |
96 | /// An owning store for the failure node if it is owned by this node. |
97 | std::unique_ptr<MatcherNode> failureNodeStorage; |
98 | |
99 | /// A unique identifier for the derived matcher node, used for type casting. |
100 | TypeID matcherTypeID; |
101 | }; |
102 | |
103 | //===----------------------------------------------------------------------===// |
104 | // BoolNode |
105 | //===----------------------------------------------------------------------===// |
106 | |
107 | /// A BoolNode denotes a question with a boolean-like result. These nodes branch |
108 | /// to a single node on a successful result, otherwise defaulting to the failure |
109 | /// node. |
110 | struct BoolNode : public MatcherNode { |
111 | BoolNode(Position *position, Qualifier *question, Qualifier *answer, |
112 | std::unique_ptr<MatcherNode> successNode, |
113 | std::unique_ptr<MatcherNode> failureNode = nullptr); |
114 | |
115 | /// Returns if the given matcher node is an instance of this class, used to |
116 | /// support type casting. |
117 | static bool classof(const MatcherNode *node) { |
118 | return node->getMatcherTypeID() == TypeID::get<BoolNode>(); |
119 | } |
120 | |
121 | /// Returns the expected answer of this boolean node. |
122 | Qualifier *getAnswer() const { return answer; } |
123 | |
124 | /// Returns the node that should be visited on success. |
125 | std::unique_ptr<MatcherNode> &getSuccessNode() { return successNode; } |
126 | |
127 | private: |
128 | /// The expected answer of this boolean node. |
129 | Qualifier *answer; |
130 | |
131 | /// The next node if this node succeeds. Otherwise, go to the failure node. |
132 | std::unique_ptr<MatcherNode> successNode; |
133 | }; |
134 | |
135 | //===----------------------------------------------------------------------===// |
136 | // ExitNode |
137 | //===----------------------------------------------------------------------===// |
138 | |
139 | /// An ExitNode is a special sentinel node that denotes the end of matcher. |
140 | struct ExitNode : public MatcherNode { |
141 | ExitNode() : MatcherNode(TypeID::get<ExitNode>()) {} |
142 | |
143 | /// Returns if the given matcher node is an instance of this class, used to |
144 | /// support type casting. |
145 | static bool classof(const MatcherNode *node) { |
146 | return node->getMatcherTypeID() == TypeID::get<ExitNode>(); |
147 | } |
148 | }; |
149 | |
150 | //===----------------------------------------------------------------------===// |
151 | // SuccessNode |
152 | //===----------------------------------------------------------------------===// |
153 | |
154 | /// A SuccessNode denotes that a given high level pattern has successfully been |
155 | /// matched. This does not terminate the matcher, as there may be multiple |
156 | /// successful matches. |
157 | struct SuccessNode : public MatcherNode { |
158 | explicit SuccessNode(pdl::PatternOp pattern, Value root, |
159 | std::unique_ptr<MatcherNode> failureNode); |
160 | |
161 | /// Returns if the given matcher node is an instance of this class, used to |
162 | /// support type casting. |
163 | static bool classof(const MatcherNode *node) { |
164 | return node->getMatcherTypeID() == TypeID::get<SuccessNode>(); |
165 | } |
166 | |
167 | /// Return the high level pattern operation that is matched with this node. |
168 | pdl::PatternOp getPattern() const { return pattern; } |
169 | |
170 | /// Return the chosen root of the pattern. |
171 | Value getRoot() const { return root; } |
172 | |
173 | private: |
174 | /// The high level pattern operation that was successfully matched with this |
175 | /// node. |
176 | pdl::PatternOp pattern; |
177 | |
178 | /// The chosen root of the pattern. |
179 | Value root; |
180 | }; |
181 | |
182 | //===----------------------------------------------------------------------===// |
183 | // SwitchNode |
184 | //===----------------------------------------------------------------------===// |
185 | |
186 | /// A SwitchNode denotes a question with multiple potential results. These nodes |
187 | /// branch to a specific node based on the result of the question. |
188 | struct SwitchNode : public MatcherNode { |
189 | SwitchNode(Position *position, Qualifier *question); |
190 | |
191 | /// Returns if the given matcher node is an instance of this class, used to |
192 | /// support type casting. |
193 | static bool classof(const MatcherNode *node) { |
194 | return node->getMatcherTypeID() == TypeID::get<SwitchNode>(); |
195 | } |
196 | |
197 | /// Returns the children of this switch node. The children are contained |
198 | /// within a mapping between the various case answers to destination matcher |
199 | /// nodes. |
200 | using ChildMapT = llvm::MapVector<Qualifier *, std::unique_ptr<MatcherNode>>; |
201 | ChildMapT &getChildren() { return children; } |
202 | |
203 | /// Returns the child at the given index. |
204 | std::pair<Qualifier *, std::unique_ptr<MatcherNode>> &getChild(unsigned i) { |
205 | assert(i < children.size() && "invalid child index" ); |
206 | return *std::next(x: children.begin(), n: i); |
207 | } |
208 | |
209 | private: |
210 | /// Switch predicate "answers" select the child. Answers that are not found |
211 | /// default to the failure node. |
212 | ChildMapT children; |
213 | }; |
214 | |
215 | } // namespace pdl_to_pdl_interp |
216 | } // namespace mlir |
217 | |
218 | #endif // MLIR_CONVERSION_PDLTOPDLINTERP_PREDICATETREE_H_ |
219 | |