1 | //===- llvm/SymbolTableListTraits.h - Traits for iplist ---------*- C++ -*-===// |
2 | // |
3 | // The LLVM Compiler Infrastructure |
4 | // |
5 | // This file is distributed under the University of Illinois Open Source |
6 | // License. See LICENSE.TXT for details. |
7 | // |
8 | //===----------------------------------------------------------------------===// |
9 | // |
10 | // This file defines a generic class that is used to implement the automatic |
11 | // symbol table manipulation that occurs when you put (for example) a named |
12 | // instruction into a basic block. |
13 | // |
14 | // The way that this is implemented is by using a special traits class with the |
15 | // intrusive list that makes up the list of instructions in a basic block. When |
16 | // a new element is added to the list of instructions, the traits class is |
17 | // notified, allowing the symbol table to be updated. |
18 | // |
19 | // This generic class implements the traits class. It must be generic so that |
20 | // it can work for all uses it, which include lists of instructions, basic |
21 | // blocks, arguments, functions, global variables, etc... |
22 | // |
23 | //===----------------------------------------------------------------------===// |
24 | |
25 | #ifndef LLVM_IR_SYMBOLTABLELISTTRAITS_H |
26 | #define LLVM_IR_SYMBOLTABLELISTTRAITS_H |
27 | |
28 | #include "llvm/ADT/ilist.h" |
29 | #include "llvm/ADT/simple_ilist.h" |
30 | #include <cstddef> |
31 | |
32 | namespace llvm { |
33 | |
34 | class Argument; |
35 | class BasicBlock; |
36 | class Function; |
37 | class GlobalAlias; |
38 | class GlobalIFunc; |
39 | class GlobalVariable; |
40 | class Instruction; |
41 | class Module; |
42 | class ValueSymbolTable; |
43 | |
44 | /// Template metafunction to get the parent type for a symbol table list. |
45 | /// |
46 | /// Implementations create a typedef called \c type so that we only need a |
47 | /// single template parameter for the list and traits. |
48 | template <typename NodeTy> struct SymbolTableListParentType {}; |
49 | |
50 | #define DEFINE_SYMBOL_TABLE_PARENT_TYPE(NODE, PARENT) \ |
51 | template <> struct SymbolTableListParentType<NODE> { using type = PARENT; }; |
52 | DEFINE_SYMBOL_TABLE_PARENT_TYPE(Instruction, BasicBlock) |
53 | DEFINE_SYMBOL_TABLE_PARENT_TYPE(BasicBlock, Function) |
54 | DEFINE_SYMBOL_TABLE_PARENT_TYPE(Argument, Function) |
55 | DEFINE_SYMBOL_TABLE_PARENT_TYPE(Function, Module) |
56 | DEFINE_SYMBOL_TABLE_PARENT_TYPE(GlobalVariable, Module) |
57 | DEFINE_SYMBOL_TABLE_PARENT_TYPE(GlobalAlias, Module) |
58 | DEFINE_SYMBOL_TABLE_PARENT_TYPE(GlobalIFunc, Module) |
59 | #undef DEFINE_SYMBOL_TABLE_PARENT_TYPE |
60 | |
61 | template <typename NodeTy> class SymbolTableList; |
62 | |
63 | // ValueSubClass - The type of objects that I hold, e.g. Instruction. |
64 | // ItemParentClass - The type of object that owns the list, e.g. BasicBlock. |
65 | // |
66 | template <typename ValueSubClass> |
67 | class SymbolTableListTraits : public ilist_alloc_traits<ValueSubClass> { |
68 | using ListTy = SymbolTableList<ValueSubClass>; |
69 | using iterator = typename simple_ilist<ValueSubClass>::iterator; |
70 | using ItemParentClass = |
71 | typename SymbolTableListParentType<ValueSubClass>::type; |
72 | |
73 | public: |
74 | SymbolTableListTraits() = default; |
75 | |
76 | private: |
77 | /// getListOwner - Return the object that owns this list. If this is a list |
78 | /// of instructions, it returns the BasicBlock that owns them. |
79 | ItemParentClass *getListOwner() { |
80 | size_t Offset(size_t(&((ItemParentClass*)nullptr->*ItemParentClass:: |
81 | getSublistAccess(static_cast<ValueSubClass*>(nullptr))))); |
82 | ListTy *Anchor(static_cast<ListTy *>(this)); |
83 | return reinterpret_cast<ItemParentClass*>(reinterpret_cast<char*>(Anchor)- |
84 | Offset); |
85 | } |
86 | |
87 | static ListTy &getList(ItemParentClass *Par) { |
88 | return Par->*(Par->getSublistAccess((ValueSubClass*)nullptr)); |
89 | } |
90 | |
91 | static ValueSymbolTable *getSymTab(ItemParentClass *Par) { |
92 | return Par ? toPtr(Par->getValueSymbolTable()) : nullptr; |
93 | } |
94 | |
95 | public: |
96 | void addNodeToList(ValueSubClass *V); |
97 | void removeNodeFromList(ValueSubClass *V); |
98 | void transferNodesFromList(SymbolTableListTraits &L2, iterator first, |
99 | iterator last); |
100 | // private: |
101 | template<typename TPtr> |
102 | void setSymTabObject(TPtr *, TPtr); |
103 | static ValueSymbolTable *toPtr(ValueSymbolTable *P) { return P; } |
104 | static ValueSymbolTable *toPtr(ValueSymbolTable &R) { return &R; } |
105 | }; |
106 | |
107 | /// List that automatically updates parent links and symbol tables. |
108 | /// |
109 | /// When nodes are inserted into and removed from this list, the associated |
110 | /// symbol table will be automatically updated. Similarly, parent links get |
111 | /// updated automatically. |
112 | template <class T> |
113 | class SymbolTableList |
114 | : public iplist_impl<simple_ilist<T>, SymbolTableListTraits<T>> {}; |
115 | |
116 | } // end namespace llvm |
117 | |
118 | #endif // LLVM_IR_SYMBOLTABLELISTTRAITS_H |
119 | |