1 //===- llvm/SymbolTableListTraits.h - Traits for iplist ---------*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
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.
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.
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...
23 //===----------------------------------------------------------------------===//
25 #ifndef LLVM_IR_SYMBOLTABLELISTTRAITS_H
26 #define LLVM_IR_SYMBOLTABLELISTTRAITS_H
28 #include "llvm/ADT/ilist.h"
29 #include "llvm/ADT/simple_ilist.h"
42 class ValueSymbolTable;
44 /// Template metafunction to get the parent type for a symbol table list.
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 {};
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
61 template <typename NodeTy> class SymbolTableList;
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.
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;
74 SymbolTableListTraits() = default;
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)-
87 static ListTy &getList(ItemParentClass *Par) {
88 return Par->*(Par->getSublistAccess((ValueSubClass*)nullptr));
91 static ValueSymbolTable *getSymTab(ItemParentClass *Par) {
92 return Par ? toPtr(Par->getValueSymbolTable()) : nullptr;
96 void addNodeToList(ValueSubClass *V);
97 void removeNodeFromList(ValueSubClass *V);
98 void transferNodesFromList(SymbolTableListTraits &L2, iterator first,
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; }
107 /// List that automatically updates parent links and symbol tables.
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.
113 class SymbolTableList
114 : public iplist_impl<simple_ilist<T>, SymbolTableListTraits<T>> {};
116 } // end namespace llvm
118 #endif // LLVM_IR_SYMBOLTABLELISTTRAITS_H