1 //===- llvm/IR/TypeFinder.h - Class to find used struct types ---*- 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 the declaration of the TypeFinder class.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #ifndef LLVM_IR_TYPEFINDER_H
14 #define LLVM_IR_TYPEFINDER_H
15 
16 #include "llvm/ADT/DenseSet.h"
17 #include <cstddef>
18 #include <vector>
19 
20 namespace llvm {
21 
22 class MDNode;
23 class Module;
24 class StructType;
25 class Type;
26 class Value;
27 
28 /// TypeFinder - Walk over a module, identifying all of the types that are
29 /// used by the module.
30 class TypeFinder {
31   // To avoid walking constant expressions multiple times and other IR
32   // objects, we keep several helper maps.
33   DenseSet<const Value*> VisitedConstants;
34   DenseSet<const MDNode *> VisitedMetadata;
35   DenseSet<Type*> VisitedTypes;
36 
37   std::vector<StructType*> StructTypes;
38   bool OnlyNamed = false;
39 
40 public:
41   TypeFinder() = default;
42 
43   void run(const Module &M, bool onlyNamed);
44   void clear();
45 
46   using iterator = std::vector<StructType*>::iterator;
47   using const_iterator = std::vector<StructType*>::const_iterator;
48 
begin()49   iterator begin() { return StructTypes.begin(); }
end()50   iterator end() { return StructTypes.end(); }
51 
begin()52   const_iterator begin() const { return StructTypes.begin(); }
end()53   const_iterator end() const { return StructTypes.end(); }
54 
empty()55   bool empty() const { return StructTypes.empty(); }
size()56   size_t size() const { return StructTypes.size(); }
erase(iterator I,iterator E)57   iterator erase(iterator I, iterator E) { return StructTypes.erase(I, E); }
58 
59   StructType *&operator[](unsigned Idx) { return StructTypes[Idx]; }
60 
getVisitedMetadata()61   DenseSet<const MDNode *> &getVisitedMetadata() { return VisitedMetadata; }
62 
63 private:
64   /// incorporateType - This method adds the type to the list of used
65   /// structures if it's not in there already.
66   void incorporateType(Type *Ty);
67 
68   /// incorporateValue - This method is used to walk operand lists finding types
69   /// hiding in constant expressions and other operands that won't be walked in
70   /// other ways.  GlobalValues, basic blocks, instructions, and inst operands
71   /// are all explicitly enumerated.
72   void incorporateValue(const Value *V);
73 
74   /// incorporateMDNode - This method is used to walk the operands of an MDNode
75   /// to find types hiding within.
76   void incorporateMDNode(const MDNode *V);
77 };
78 
79 } // end namespace llvm
80 
81 #endif // LLVM_IR_TYPEFINDER_H
82