Argument.h revision 263508 
1//===-- llvm/Argument.h - Definition of the Argument class ------*- 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 declares the Argument class.
11//
12//===----------------------------------------------------------------------===//
13
14#ifndef LLVM_IR_ARGUMENT_H
15#define LLVM_IR_ARGUMENT_H
16
17#include "llvm/ADT/Twine.h"
18#include "llvm/ADT/ilist_node.h"
19#include "llvm/IR/Attributes.h"
20#include "llvm/IR/Value.h"
21
22namespace llvm {
23
24template<typename ValueSubClass, typename ItemParentClass>
25  class SymbolTableListTraits;
26
27/// \brief LLVM Argument representation
28///
29/// This class represents an incoming formal argument to a Function. A formal
30/// argument, since it is ``formal'', does not contain an actual value but
31/// instead represents the type, argument number, and attributes of an argument
32/// for a specific function. When used in the body of said function, the
33/// argument of course represents the value of the actual argument that the
34/// function was called with.
35class Argument : public Value, public ilist_node<Argument> {
36  virtual void anchor();
37  Function *Parent;
38
39  friend class SymbolTableListTraits<Argument, Function>;
40  void setParent(Function *parent);
41
42public:
43  /// \brief Constructor.
44  ///
45  /// If \p F is specified, the argument is inserted at the end of the argument
46  /// list for \p F.
47  explicit Argument(Type *Ty, const Twine &Name = "", Function *F = 0);
48
49  inline const Function *getParent() const { return Parent; }
50  inline       Function *getParent()       { return Parent; }
51
52  /// \brief Return the index of this formal argument in its containing
53  /// function.
54  ///
55  /// For example in "void foo(int a, float b)" a is 0 and b is 1.
56  unsigned getArgNo() const;
57
58  /// \brief Return true if this argument has the byval attribute on it in its
59  /// containing function.
60  bool hasByValAttr() const;
61
62  /// \brief If this is a byval argument, return its alignment.
63  unsigned getParamAlignment() const;
64
65  /// \brief Return true if this argument has the nest attribute on it in its
66  /// containing function.
67  bool hasNestAttr() const;
68
69  /// \brief Return true if this argument has the noalias attribute on it in its
70  /// containing function.
71  bool hasNoAliasAttr() const;
72
73  /// \brief Return true if this argument has the nocapture attribute on it in
74  /// its containing function.
75  bool hasNoCaptureAttr() const;
76
77  /// \brief Return true if this argument has the sret attribute on it in its
78  /// containing function.
79  bool hasStructRetAttr() const;
80
81  /// \brief Return true if this argument has the returned attribute on it in
82  /// its containing function.
83  bool hasReturnedAttr() const;
84
85  /// \brief Return true if this argument has the readonly or readnone attribute
86  /// on it in its containing function.
87  bool onlyReadsMemory() const;
88
89
90  /// \brief Add a Attribute to an argument.
91  void addAttr(AttributeSet AS);
92
93  /// \brief Remove a Attribute from an argument.
94  void removeAttr(AttributeSet AS);
95
96  /// \brief Method for support type inquiry through isa, cast, and
97  /// dyn_cast.
98  static inline bool classof(const Value *V) {
99    return V->getValueID() == ArgumentVal;
100  }
101};
102
103} // End llvm namespace
104
105#endif
106