//===-- llvm/GlobalValue.h - Class to represent a global value --*- C++ -*-===//
-//
+//
// The LLVM Compiler Infrastructure
//
// This file was developed by the LLVM research group and is distributed under
// the University of Illinois Open Source License. See LICENSE.TXT for details.
-//
+//
//===----------------------------------------------------------------------===//
//
// This file is a common base class of all globally definable objects. As such,
GlobalValue(const GlobalValue &); // do not implement
public:
enum LinkageTypes {
- ExternalLinkage, // Externally visible function
- LinkOnceLinkage, // Keep one copy of named function when linking (inline)
- WeakLinkage, // Keep one copy of named function when linking (weak)
- AppendingLinkage, // Special purpose, only applies to global arrays
- InternalLinkage // Rename collisions when linking (static functions)
+ ExternalLinkage, /// Externally visible function
+ LinkOnceLinkage, /// Keep one copy of named function when linking (inline)
+ WeakLinkage, /// Keep one copy of named function when linking (weak)
+ AppendingLinkage, /// Special purpose, only applies to global arrays
+ InternalLinkage, /// Rename collisions when linking (static functions)
+ GhostLinkage /// Stand-in functions for streaming fns from BC files
};
protected:
- GlobalValue(const Type *Ty, ValueTy vty, LinkageTypes linkage,
- const std::string &name = "")
- : Constant(Ty, vty, name), Linkage(linkage), Parent(0) { }
+ GlobalValue(const Type *Ty, ValueTy vty, Use *Ops, unsigned NumOps,
+ LinkageTypes linkage, const std::string &name = "")
+ : Constant(Ty, vty, Ops, NumOps, name),
+ Parent(0), Linkage(linkage), Alignment(0) { }
- LinkageTypes Linkage; // The linkage of this global
Module *Parent;
+ LinkageTypes Linkage; // The linkage of this global
+ unsigned Alignment; // Alignment of this symbol, must be power of two
+ std::string Section; // Section to emit this into, empty mean default
public:
- virtual ~GlobalValue();
+ ~GlobalValue() {
+ removeDeadConstantUsers(); // remove any dead constants using this.
+ }
+ unsigned getAlignment() const { return Alignment; }
+ void setAlignment(unsigned Align) {
+ assert((Align & (Align-1)) == 0 && "Alignment is not a power of 2!");
+ Alignment = Align;
+ }
+
+ bool hasSection() const { return !Section.empty(); }
+ const std::string &getSection() const { return Section; }
+ void setSection(const std::string &S) { Section = S; }
+
/// If the usage is empty (except transitively dead constants), then this
- /// global value can can be safely deleted since the destructor wll
+ /// global value can can be safely deleted since the destructor will
/// delete the dead constants as well.
- /// @brief Determine if theusage of this global value is empty except
+ /// @brief Determine if the usage of this global value is empty except
/// for transitively dead constants.
bool use_empty_except_constants();
void setLinkage(LinkageTypes LT) { Linkage = LT; }
LinkageTypes getLinkage() const { return Linkage; }
- /// Override from Constant class. No GlobalValue's have null values so
- /// this always returns false.
+ /// hasNotBeenReadFromBytecode - If a module provider is being used to lazily
+ /// stream in functions from disk, this method can be used to check to see if
+ /// the function has been read in yet or not. Unless you are working on the
+ /// JIT or something else that streams stuff in lazily, you don't need to
+ /// worry about this.
+ bool hasNotBeenReadFromBytecode() const { return Linkage == GhostLinkage; }
+
+ /// Override from Constant class. No GlobalValue's are null values so this
+ /// always returns false.
virtual bool isNullValue() const { return false; }
/// Override from Constant class.
/// that want to check to see if a global is unused, but don't want to deal
/// with potentially dead constants hanging off of the globals.
///
- /// This function returns true if the global value is now dead. If all
- /// users of this global are not dead, this method may return false and
- /// leave some of them around.
- bool removeDeadConstantUsers();
+ /// This method tries to make the global dead. If it detects a user that
+ /// would prevent it from becoming completely dead, it gives up early,
+ /// potentially leaving some dead constant users around.
+ void removeDeadConstantUsers();
// Methods for support type inquiry through isa, cast, and dyn_cast:
- static inline bool classof(const GlobalValue *T) { return true; }
+ static inline bool classof(const GlobalValue *) { return true; }
static inline bool classof(const Value *V) {
- return V->getValueType() == Value::FunctionVal ||
+ return V->getValueType() == Value::FunctionVal ||
V->getValueType() == Value::GlobalVariableVal;
}
};