1 //===-- llvm/Argument.h - Definition of the Argument class ------*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file declares the Argument class.
12 //===----------------------------------------------------------------------===//
14 #ifndef LLVM_IR_ARGUMENT_H
15 #define LLVM_IR_ARGUMENT_H
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"
24 template <typename NodeTy> class SymbolTableListTraits;
26 /// \brief LLVM Argument representation
28 /// This class represents an incoming formal argument to a Function. A formal
29 /// argument, since it is ``formal'', does not contain an actual value but
30 /// instead represents the type, argument number, and attributes of an argument
31 /// for a specific function. When used in the body of said function, the
32 /// argument of course represents the value of the actual argument that the
33 /// function was called with.
34 class Argument : public Value, public ilist_node<Argument> {
35 virtual void anchor();
38 friend class SymbolTableListTraits<Argument>;
39 void setParent(Function *parent);
42 /// \brief Constructor.
44 /// If \p F is specified, the argument is inserted at the end of the argument
46 explicit Argument(Type *Ty, const Twine &Name = "", Function *F = nullptr);
48 inline const Function *getParent() const { return Parent; }
49 inline Function *getParent() { return Parent; }
51 /// \brief Return the index of this formal argument in its containing
54 /// For example in "void foo(int a, float b)" a is 0 and b is 1.
55 unsigned getArgNo() const;
57 /// \brief Return true if this argument has the nonnull attribute on it in
58 /// its containing function. Also returns true if at least one byte is known
59 /// to be dereferenceable and the pointer is in addrspace(0).
60 bool hasNonNullAttr() const;
62 /// \brief If this argument has the dereferenceable attribute on it in its
63 /// containing function, return the number of bytes known to be
64 /// dereferenceable. Otherwise, zero is returned.
65 uint64_t getDereferenceableBytes() const;
67 /// \brief If this argument has the dereferenceable_or_null attribute on
68 /// it in its containing function, return the number of bytes known to be
69 /// dereferenceable. Otherwise, zero is returned.
70 uint64_t getDereferenceableOrNullBytes() const;
72 /// \brief Return true if this argument has the byval attribute on it in its
73 /// containing function.
74 bool hasByValAttr() const;
76 /// \brief Return true if this argument has the swiftself attribute.
77 bool hasSwiftSelfAttr() const;
79 /// \brief Return true if this argument has the swifterror attribute.
80 bool hasSwiftErrorAttr() const;
82 /// \brief Return true if this argument has the byval attribute or inalloca
83 /// attribute on it in its containing function. These attributes both
84 /// represent arguments being passed by value.
85 bool hasByValOrInAllocaAttr() const;
87 /// \brief If this is a byval or inalloca argument, return its alignment.
88 unsigned getParamAlignment() const;
90 /// \brief Return true if this argument has the nest attribute on it in its
91 /// containing function.
92 bool hasNestAttr() const;
94 /// \brief Return true if this argument has the noalias attribute on it in its
95 /// containing function.
96 bool hasNoAliasAttr() const;
98 /// \brief Return true if this argument has the nocapture attribute on it in
99 /// its containing function.
100 bool hasNoCaptureAttr() const;
102 /// \brief Return true if this argument has the sret attribute on it in its
103 /// containing function.
104 bool hasStructRetAttr() const;
106 /// \brief Return true if this argument has the returned attribute on it in
107 /// its containing function.
108 bool hasReturnedAttr() const;
110 /// \brief Return true if this argument has the readonly or readnone attribute
111 /// on it in its containing function.
112 bool onlyReadsMemory() const;
114 /// \brief Return true if this argument has the inalloca attribute on it in
115 /// its containing function.
116 bool hasInAllocaAttr() const;
118 /// \brief Return true if this argument has the zext attribute on it in its
119 /// containing function.
120 bool hasZExtAttr() const;
122 /// \brief Return true if this argument has the sext attribute on it in its
123 /// containing function.
124 bool hasSExtAttr() const;
126 /// \brief Add a Attribute to an argument.
127 void addAttr(AttributeSet AS);
129 void addAttr(Attribute::AttrKind Kind) {
130 addAttr(AttributeSet::get(getContext(), getArgNo() + 1, Kind));
133 /// \brief Remove a Attribute from an argument.
134 void removeAttr(AttributeSet AS);
136 void removeAttr(Attribute::AttrKind Kind) {
137 removeAttr(AttributeSet::get(getContext(), getArgNo() + 1, Kind));
140 /// \brief Checks if an argument has a given attribute.
141 bool hasAttribute(Attribute::AttrKind Kind) const;
143 /// \brief Method for support type inquiry through isa, cast, and
145 static inline bool classof(const Value *V) {
146 return V->getValueID() == ArgumentVal;
150 } // End llvm namespace