llvm-6502/include/llvm/IR/GlobalAlias.h
Rafael Espindola 21cfedee05 Revert "Implement global merge optimization for global variables."
This reverts commit r208934.

The patch depends on aliases to GEPs with non zero offsets. That is not
supported and fairly broken.

The good news is that GlobalAlias is being redesigned and will have support
for offsets, so this patch should be a nice match for it.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@208978 91177308-0d34-0410-b5e6-96231b3b80d8
2014-05-16 13:02:18 +00:00

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3.0 KiB
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//===-------- llvm/GlobalAlias.h - GlobalAlias class ------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file contains the declaration of the GlobalAlias class, which
// represents a single function or variable alias in the IR.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_IR_GLOBALALIAS_H
#define LLVM_IR_GLOBALALIAS_H
#include "llvm/ADT/Twine.h"
#include "llvm/ADT/ilist_node.h"
#include "llvm/IR/GlobalValue.h"
#include "llvm/IR/OperandTraits.h"
namespace llvm {
class Module;
template<typename ValueSubClass, typename ItemParentClass>
class SymbolTableListTraits;
class GlobalAlias : public GlobalValue, public ilist_node<GlobalAlias> {
friend class SymbolTableListTraits<GlobalAlias, Module>;
void operator=(const GlobalAlias &) LLVM_DELETED_FUNCTION;
GlobalAlias(const GlobalAlias &) LLVM_DELETED_FUNCTION;
void setParent(Module *parent);
public:
// allocate space for exactly one operand
void *operator new(size_t s) {
return User::operator new(s, 1);
}
/// GlobalAlias ctor - If a parent module is specified, the alias is
/// automatically inserted into the end of the specified module's alias list.
GlobalAlias(Type *Ty, LinkageTypes Linkage, const Twine &Name = "",
Constant* Aliasee = nullptr, Module *Parent = nullptr);
/// Provide fast operand accessors
DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Constant);
/// removeFromParent - This method unlinks 'this' from the containing module,
/// but does not delete it.
///
void removeFromParent() override;
/// eraseFromParent - This method unlinks 'this' from the containing module
/// and deletes it.
///
void eraseFromParent() override;
/// set/getAliasee - These methods retrive and set alias target.
void setAliasee(Constant *GV);
const Constant *getAliasee() const {
return getOperand(0);
}
Constant *getAliasee() {
return getOperand(0);
}
/// This method tries to ultimately resolve the alias by going through the
/// aliasing chain and trying to find the very last global. Returns NULL if a
/// cycle was found.
GlobalObject *getAliasedGlobal();
const GlobalObject *getAliasedGlobal() const {
return const_cast<GlobalAlias *>(this)->getAliasedGlobal();
}
static bool isValidLinkage(LinkageTypes L) {
return isExternalLinkage(L) || isLocalLinkage(L) ||
isWeakLinkage(L) || isLinkOnceLinkage(L);
}
// Methods for support type inquiry through isa, cast, and dyn_cast:
static inline bool classof(const Value *V) {
return V->getValueID() == Value::GlobalAliasVal;
}
};
template <>
struct OperandTraits<GlobalAlias> :
public FixedNumOperandTraits<GlobalAlias, 1> {
};
DEFINE_TRANSPARENT_OPERAND_ACCESSORS(GlobalAlias, Constant)
} // End llvm namespace
#endif