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 = nullptr); 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 nonnull attribute on it in 59 /// its containing function. Also returns true if at least one byte is known 60 /// to be dereferenceable and the pointer is in addrspace(0). 61 bool hasNonNullAttr() const; 62 63 /// \brief If this argument has the dereferenceable attribute on it in its 64 /// containing function, return the number of bytes known to be 65 /// dereferenceable. Otherwise, zero is returned. 66 uint64_t getDereferenceableBytes() const; 67 68 /// \brief Return true if this argument has the byval attribute on it in its 69 /// containing function. 70 bool hasByValAttr() const; 71 72 /// \brief Return true if this argument has the byval attribute or inalloca 73 /// attribute on it in its containing function. These attributes both 74 /// represent arguments being passed by value. 75 bool hasByValOrInAllocaAttr() const; 76 77 /// \brief If this is a byval or inalloca argument, return its alignment. 78 unsigned getParamAlignment() const; 79 80 /// \brief Return true if this argument has the nest attribute on it in its 81 /// containing function. 82 bool hasNestAttr() const; 83 84 /// \brief Return true if this argument has the noalias attribute on it in its 85 /// containing function. 86 bool hasNoAliasAttr() const; 87 88 /// \brief Return true if this argument has the nocapture attribute on it in 89 /// its containing function. 90 bool hasNoCaptureAttr() const; 91 92 /// \brief Return true if this argument has the sret attribute on it in its 93 /// containing function. 94 bool hasStructRetAttr() const; 95 96 /// \brief Return true if this argument has the returned attribute on it in 97 /// its containing function. 98 bool hasReturnedAttr() const; 99 100 /// \brief Return true if this argument has the readonly or readnone attribute 101 /// on it in its containing function. 102 bool onlyReadsMemory() const; 103 104 /// \brief Return true if this argument has the inalloca attribute on it in 105 /// its containing function. 106 bool hasInAllocaAttr() const; 107 108 /// \brief Return true if this argument has the zext attribute on it in its 109 /// containing function. 110 bool hasZExtAttr() const; 111 112 /// \brief Return true if this argument has the sext attribute on it in its 113 /// containing function. 114 bool hasSExtAttr() const; 115 116 /// \brief Add a Attribute to an argument. 117 void addAttr(AttributeSet AS); 118 119 /// \brief Remove a Attribute from an argument. 120 void removeAttr(AttributeSet AS); 121 122 /// \brief Method for support type inquiry through isa, cast, and 123 /// dyn_cast. 124 static inline bool classof(const Value *V) { 125 return V->getValueID() == ArgumentVal; 126 } 127}; 128 129} // End llvm namespace 130 131#endif 132