llvm-6502/include/llvm/SymbolTableListTraits.h
Duncan Sands 39dea6ff76 Avoid many "variable 'Sub' set but not used [-Wunused-but-set-variable]" warnings
with gcc-4.6.  The warning is wrong, since Sub *is* used (perhaps gcc is confused
because the use of Sub is constant folded away?), but since it is trivial to avoid,
and massively reduces the amount of warning spew, just workaround the wrong warning.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@105788 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-10 15:06:05 +00:00

80 lines
3.1 KiB
C++

//===-- llvm/SymbolTableListTraits.h - Traits for iplist --------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file defines a generic class that is used to implement the automatic
// symbol table manipulation that occurs when you put (for example) a named
// instruction into a basic block.
//
// The way that this is implemented is by using a special traits class with the
// intrusive list that makes up the list of instructions in a basic block. When
// a new element is added to the list of instructions, the traits class is
// notified, allowing the symbol table to be updated.
//
// This generic class implements the traits class. It must be generic so that
// it can work for all uses it, which include lists of instructions, basic
// blocks, arguments, functions, global variables, etc...
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_SYMBOLTABLELISTTRAITS_H
#define LLVM_SYMBOLTABLELISTTRAITS_H
#include "llvm/ADT/ilist.h"
namespace llvm {
class ValueSymbolTable;
template<typename NodeTy> class ilist_iterator;
template<typename NodeTy, typename Traits> class iplist;
template<typename Ty> struct ilist_traits;
// ValueSubClass - The type of objects that I hold, e.g. Instruction.
// ItemParentClass - The type of object that owns the list, e.g. BasicBlock.
//
template<typename ValueSubClass, typename ItemParentClass>
class SymbolTableListTraits : public ilist_default_traits<ValueSubClass> {
typedef ilist_traits<ValueSubClass> TraitsClass;
public:
SymbolTableListTraits() {}
/// getListOwner - Return the object that owns this list. If this is a list
/// of instructions, it returns the BasicBlock that owns them.
ItemParentClass *getListOwner() {
typedef iplist<ValueSubClass> ItemParentClass::*Sublist;
size_t Offset(size_t(&((ItemParentClass*)0->*ItemParentClass::
getSublistAccess(static_cast<ValueSubClass*>(0)))));
iplist<ValueSubClass>* Anchor(static_cast<iplist<ValueSubClass>*>(this));
return reinterpret_cast<ItemParentClass*>(reinterpret_cast<char*>(Anchor)-
Offset);
}
static iplist<ValueSubClass> &getList(ItemParentClass *Par) {
return Par->*(Par->getSublistAccess((ValueSubClass*)0));
}
static ValueSymbolTable *getSymTab(ItemParentClass *Par) {
return Par ? toPtr(Par->getValueSymbolTable()) : 0;
}
void addNodeToList(ValueSubClass *V);
void removeNodeFromList(ValueSubClass *V);
void transferNodesFromList(ilist_traits<ValueSubClass> &L2,
ilist_iterator<ValueSubClass> first,
ilist_iterator<ValueSubClass> last);
//private:
template<typename TPtr>
void setSymTabObject(TPtr *, TPtr);
static ValueSymbolTable *toPtr(ValueSymbolTable *P) { return P; }
static ValueSymbolTable *toPtr(ValueSymbolTable &R) { return &R; }
};
} // End llvm namespace
#endif