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
30namespace llvm {
31class ValueSymbolTable;
32
33template<typename NodeTy> class ilist_iterator;
34template<typename NodeTy, typename Traits> class iplist;
35template<typename Ty> struct ilist_traits;
36
37// ValueSubClass   - The type of objects that I hold, e.g. Instruction.
38// ItemParentClass - The type of object that owns the list, e.g. BasicBlock.
39//
40template<typename ValueSubClass, typename ItemParentClass>
41class SymbolTableListTraits : public ilist_default_traits<ValueSubClass> {
42  typedef ilist_traits<ValueSubClass> TraitsClass;
43public:
44  SymbolTableListTraits() {}
45
46  /// getListOwner - Return the object that owns this list.  If this is a list
47  /// of instructions, it returns the BasicBlock that owns them.
48  ItemParentClass *getListOwner() {
49    size_t Offset(size_t(&((ItemParentClass*)nullptr->*ItemParentClass::
50                           getSublistAccess(static_cast<ValueSubClass*>(nullptr)))));
51    iplist<ValueSubClass>* Anchor(static_cast<iplist<ValueSubClass>*>(this));
52    return reinterpret_cast<ItemParentClass*>(reinterpret_cast<char*>(Anchor)-
53                                              Offset);
54  }
55
56  static iplist<ValueSubClass> &getList(ItemParentClass *Par) {
57    return Par->*(Par->getSublistAccess((ValueSubClass*)nullptr));
58  }
59
60  static ValueSymbolTable *getSymTab(ItemParentClass *Par) {
61    return Par ? toPtr(Par->getValueSymbolTable()) : nullptr;
62  }
63
64  void addNodeToList(ValueSubClass *V);
65  void removeNodeFromList(ValueSubClass *V);
66  void transferNodesFromList(ilist_traits<ValueSubClass> &L2,
67                             ilist_iterator<ValueSubClass> first,
68                             ilist_iterator<ValueSubClass> last);
69//private:
70  template<typename TPtr>
71  void setSymTabObject(TPtr *, TPtr);
72  static ValueSymbolTable *toPtr(ValueSymbolTable *P) { return P; }
73  static ValueSymbolTable *toPtr(ValueSymbolTable &R) { return &R; }
74};
75
76} // End llvm namespace
77
78#endif
79