src/llvm/include/llvm/IR/SymbolTableListTraits.h

   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
  30 namespace llvm {
  31 class ValueSymbolTable;
  32
  33 template<typename NodeTy> class ilist_iterator;
  34 template<typename NodeTy, typename Traits> class iplist;
  35 template<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 //
  40 template<typename ValueSubClass, typename ItemParentClass>
  41 class SymbolTableListTraits : public ilist_default_traits<ValueSubClass> {
  42   typedef ilist_traits<ValueSubClass> TraitsClass;
  43 public:
  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