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//===-------- llvm/GlobalAlias.h - GlobalAlias class ------------*- C++ -*-===//
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// The LLVM Compiler Infrastructure
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// This file is distributed under the University of Illinois Open Source
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// License. See LICENSE.TXT for details.
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//===----------------------------------------------------------------------===//
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// This file contains the declaration of the GlobalAlias class, which
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// represents a single function or variable alias in the IR.
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//===----------------------------------------------------------------------===//
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#ifndef LLVM_GLOBAL_ALIAS_H
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#define LLVM_GLOBAL_ALIAS_H
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#include "llvm/GlobalValue.h"
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#include "llvm/OperandTraits.h"
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#include "llvm/ADT/ilist_node.h"
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#include "llvm/ADT/Twine.h"
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template<typename ValueSubClass, typename ItemParentClass>
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class SymbolTableListTraits;
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class GlobalAlias : public GlobalValue, public ilist_node<GlobalAlias> {
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friend class SymbolTableListTraits<GlobalAlias, Module>;
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void operator=(const GlobalAlias &); // Do not implement
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GlobalAlias(const GlobalAlias &); // Do not implement
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void setParent(Module *parent);
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// allocate space for exactly one operand
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void *operator new(size_t s) {
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return User::operator new(s, 1);
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/// GlobalAlias ctor - If a parent module is specified, the alias is
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/// automatically inserted into the end of the specified module's alias list.
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GlobalAlias(const Type *Ty, LinkageTypes Linkage, const Twine &Name = "",
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Constant* Aliasee = 0, Module *Parent = 0);
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/// Provide fast operand accessors
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DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value);
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/// isDeclaration - Is this global variable lacking an initializer? If so,
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/// the global variable is defined in some other translation unit, and is thus
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/// only a declaration here.
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virtual bool isDeclaration() const;
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/// removeFromParent - This method unlinks 'this' from the containing module,
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/// but does not delete it.
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virtual void removeFromParent();
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/// eraseFromParent - This method unlinks 'this' from the containing module
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virtual void eraseFromParent();
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/// set/getAliasee - These methods retrive and set alias target.
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void setAliasee(Constant* GV);
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const Constant* getAliasee() const {
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return cast_or_null<Constant>(getOperand(0));
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Constant* getAliasee() {
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return cast_or_null<Constant>(getOperand(0));
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/// getAliasedGlobal() - Aliasee can be either global or bitcast of
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/// global. This method retrives the global for both aliasee flavours.
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const GlobalValue* getAliasedGlobal() const;
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/// resolveAliasedGlobal() - This method tries to ultimately resolve the alias
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/// by going through the aliasing chain and trying to find the very last
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/// global. Returns NULL if a cycle was found. If stopOnWeak is false, then
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/// the whole chain aliasing chain is traversed, otherwise - only strong
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const GlobalValue* resolveAliasedGlobal(bool stopOnWeak = true) const;
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// Methods for support type inquiry through isa, cast, and dyn_cast:
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static inline bool classof(const GlobalAlias *) { return true; }
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static inline bool classof(const Value *V) {
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return V->getValueID() == Value::GlobalAliasVal;
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struct OperandTraits<GlobalAlias> : public FixedNumOperandTraits<1> {
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DEFINE_TRANSPARENT_OPERAND_ACCESSORS(GlobalAlias, Value)
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} // End llvm namespace