1 //===-- AttributeImpl.h - Attribute Internals -------------------*- 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 /// \file
11 /// \brief This file defines various helper methods and classes used by
12 /// LLVMContextImpl for creating and managing attributes.
13 ///
14 //===----------------------------------------------------------------------===//
15 
16 #ifndef LLVM_LIB_IR_ATTRIBUTEIMPL_H
17 #define LLVM_LIB_IR_ATTRIBUTEIMPL_H
18 
19 #include "llvm/ADT/FoldingSet.h"
20 #include "llvm/IR/Attributes.h"
21 #include <string>
22 
23 namespace llvm {
24 
25 class Constant;
26 class LLVMContext;
27 
28 //===----------------------------------------------------------------------===//
29 /// \class
30 /// \brief This class represents a single, uniqued attribute. That attribute
31 /// could be a single enum, a tuple, or a string.
32 class AttributeImpl : public FoldingSetNode {
33   unsigned char KindID; ///< Holds the AttrEntryKind of the attribute
34 
35   // AttributesImpl is uniqued, these should not be publicly available.
36   void operator=(const AttributeImpl &) = delete;
37   AttributeImpl(const AttributeImpl &) = delete;
38 
39 protected:
40   enum AttrEntryKind {
41     EnumAttrEntry,
42     IntAttrEntry,
43     StringAttrEntry
44   };
45 
AttributeImpl(AttrEntryKind KindID)46   AttributeImpl(AttrEntryKind KindID) : KindID(KindID) {}
47 
48 public:
49   virtual ~AttributeImpl();
50 
isEnumAttribute()51   bool isEnumAttribute() const { return KindID == EnumAttrEntry; }
isIntAttribute()52   bool isIntAttribute() const { return KindID == IntAttrEntry; }
isStringAttribute()53   bool isStringAttribute() const { return KindID == StringAttrEntry; }
54 
55   bool hasAttribute(Attribute::AttrKind A) const;
56   bool hasAttribute(StringRef Kind) const;
57 
58   Attribute::AttrKind getKindAsEnum() const;
59   uint64_t getValueAsInt() const;
60 
61   StringRef getKindAsString() const;
62   StringRef getValueAsString() const;
63 
64   /// \brief Used when sorting the attributes.
65   bool operator<(const AttributeImpl &AI) const;
66 
Profile(FoldingSetNodeID & ID)67   void Profile(FoldingSetNodeID &ID) const {
68     if (isEnumAttribute())
69       Profile(ID, getKindAsEnum(), 0);
70     else if (isIntAttribute())
71       Profile(ID, getKindAsEnum(), getValueAsInt());
72     else
73       Profile(ID, getKindAsString(), getValueAsString());
74   }
Profile(FoldingSetNodeID & ID,Attribute::AttrKind Kind,uint64_t Val)75   static void Profile(FoldingSetNodeID &ID, Attribute::AttrKind Kind,
76                       uint64_t Val) {
77     ID.AddInteger(Kind);
78     if (Val) ID.AddInteger(Val);
79   }
Profile(FoldingSetNodeID & ID,StringRef Kind,StringRef Values)80   static void Profile(FoldingSetNodeID &ID, StringRef Kind, StringRef Values) {
81     ID.AddString(Kind);
82     if (!Values.empty()) ID.AddString(Values);
83   }
84 
85   // FIXME: Remove this!
86   static uint64_t getAttrMask(Attribute::AttrKind Val);
87 };
88 
89 //===----------------------------------------------------------------------===//
90 /// \class
91 /// \brief A set of classes that contain the value of the
92 /// attribute object. There are three main categories: enum attribute entries,
93 /// represented by Attribute::AttrKind; alignment attribute entries; and string
94 /// attribute enties, which are for target-dependent attributes.
95 
96 class EnumAttributeImpl : public AttributeImpl {
97   virtual void anchor();
98   Attribute::AttrKind Kind;
99 
100 protected:
EnumAttributeImpl(AttrEntryKind ID,Attribute::AttrKind Kind)101   EnumAttributeImpl(AttrEntryKind ID, Attribute::AttrKind Kind)
102       : AttributeImpl(ID), Kind(Kind) {}
103 
104 public:
EnumAttributeImpl(Attribute::AttrKind Kind)105   EnumAttributeImpl(Attribute::AttrKind Kind)
106       : AttributeImpl(EnumAttrEntry), Kind(Kind) {}
107 
getEnumKind()108   Attribute::AttrKind getEnumKind() const { return Kind; }
109 };
110 
111 class IntAttributeImpl : public EnumAttributeImpl {
112   void anchor() override;
113   uint64_t Val;
114 
115 public:
IntAttributeImpl(Attribute::AttrKind Kind,uint64_t Val)116   IntAttributeImpl(Attribute::AttrKind Kind, uint64_t Val)
117       : EnumAttributeImpl(IntAttrEntry, Kind), Val(Val) {
118     assert((Kind == Attribute::Alignment || Kind == Attribute::StackAlignment ||
119             Kind == Attribute::Dereferenceable ||
120             Kind == Attribute::DereferenceableOrNull) &&
121            "Wrong kind for int attribute!");
122   }
123 
getValue()124   uint64_t getValue() const { return Val; }
125 };
126 
127 class StringAttributeImpl : public AttributeImpl {
128   virtual void anchor();
129   std::string Kind;
130   std::string Val;
131 
132 public:
133   StringAttributeImpl(StringRef Kind, StringRef Val = StringRef())
AttributeImpl(StringAttrEntry)134       : AttributeImpl(StringAttrEntry), Kind(Kind), Val(Val) {}
135 
getStringKind()136   StringRef getStringKind() const { return Kind; }
getStringValue()137   StringRef getStringValue() const { return Val; }
138 };
139 
140 //===----------------------------------------------------------------------===//
141 /// \class
142 /// \brief This class represents a group of attributes that apply to one
143 /// element: function, return type, or parameter.
144 class AttributeSetNode : public FoldingSetNode {
145   unsigned NumAttrs; ///< Number of attributes in this node.
146 
AttributeSetNode(ArrayRef<Attribute> Attrs)147   AttributeSetNode(ArrayRef<Attribute> Attrs) : NumAttrs(Attrs.size()) {
148     // There's memory after the node where we can store the entries in.
149     std::copy(Attrs.begin(), Attrs.end(),
150               reinterpret_cast<Attribute *>(this + 1));
151   }
152 
153   // AttributesSetNode is uniqued, these should not be publicly available.
154   void operator=(const AttributeSetNode &) = delete;
155   AttributeSetNode(const AttributeSetNode &) = delete;
156 public:
157   static AttributeSetNode *get(LLVMContext &C, ArrayRef<Attribute> Attrs);
158 
159   bool hasAttribute(Attribute::AttrKind Kind) const;
160   bool hasAttribute(StringRef Kind) const;
hasAttributes()161   bool hasAttributes() const { return NumAttrs != 0; }
162 
163   Attribute getAttribute(Attribute::AttrKind Kind) const;
164   Attribute getAttribute(StringRef Kind) const;
165 
166   unsigned getAlignment() const;
167   unsigned getStackAlignment() const;
168   uint64_t getDereferenceableBytes() const;
169   std::string getAsString(bool InAttrGrp) const;
170 
171   typedef const Attribute *iterator;
begin()172   iterator begin() const { return reinterpret_cast<iterator>(this + 1); }
end()173   iterator end() const { return begin() + NumAttrs; }
174 
Profile(FoldingSetNodeID & ID)175   void Profile(FoldingSetNodeID &ID) const {
176     Profile(ID, makeArrayRef(begin(), end()));
177   }
Profile(FoldingSetNodeID & ID,ArrayRef<Attribute> AttrList)178   static void Profile(FoldingSetNodeID &ID, ArrayRef<Attribute> AttrList) {
179     for (unsigned I = 0, E = AttrList.size(); I != E; ++I)
180       AttrList[I].Profile(ID);
181   }
182 };
183 
184 //===----------------------------------------------------------------------===//
185 /// \class
186 /// \brief This class represents a set of attributes that apply to the function,
187 /// return type, and parameters.
188 class AttributeSetImpl : public FoldingSetNode {
189   friend class AttributeSet;
190 
191   LLVMContext &Context;
192 
193   typedef std::pair<unsigned, AttributeSetNode*> IndexAttrPair;
194   unsigned NumAttrs; ///< Number of entries in this set.
195 
196   /// \brief Return a pointer to the IndexAttrPair for the specified slot.
getNode(unsigned Slot)197   const IndexAttrPair *getNode(unsigned Slot) const {
198     return reinterpret_cast<const IndexAttrPair *>(this + 1) + Slot;
199   }
200 
201   // AttributesSet is uniqued, these should not be publicly available.
202   void operator=(const AttributeSetImpl &) = delete;
203   AttributeSetImpl(const AttributeSetImpl &) = delete;
204 public:
AttributeSetImpl(LLVMContext & C,ArrayRef<std::pair<unsigned,AttributeSetNode * >> Attrs)205   AttributeSetImpl(LLVMContext &C,
206                    ArrayRef<std::pair<unsigned, AttributeSetNode *> > Attrs)
207       : Context(C), NumAttrs(Attrs.size()) {
208 #ifndef NDEBUG
209     if (Attrs.size() >= 2) {
210       for (const std::pair<unsigned, AttributeSetNode *> *i = Attrs.begin() + 1,
211                                                          *e = Attrs.end();
212            i != e; ++i) {
213         assert((i-1)->first <= i->first && "Attribute set not ordered!");
214       }
215     }
216 #endif
217     // There's memory after the node where we can store the entries in.
218     std::copy(Attrs.begin(), Attrs.end(),
219               reinterpret_cast<IndexAttrPair *>(this + 1));
220   }
221 
222   /// \brief Get the context that created this AttributeSetImpl.
getContext()223   LLVMContext &getContext() { return Context; }
224 
225   /// \brief Return the number of attributes this AttributeSet contains.
getNumAttributes()226   unsigned getNumAttributes() const { return NumAttrs; }
227 
228   /// \brief Get the index of the given "slot" in the AttrNodes list. This index
229   /// is the index of the return, parameter, or function object that the
230   /// attributes are applied to, not the index into the AttrNodes list where the
231   /// attributes reside.
getSlotIndex(unsigned Slot)232   unsigned getSlotIndex(unsigned Slot) const {
233     return getNode(Slot)->first;
234   }
235 
236   /// \brief Retrieve the attributes for the given "slot" in the AttrNode list.
237   /// \p Slot is an index into the AttrNodes list, not the index of the return /
238   /// parameter/ function which the attributes apply to.
getSlotAttributes(unsigned Slot)239   AttributeSet getSlotAttributes(unsigned Slot) const {
240     return AttributeSet::get(Context, *getNode(Slot));
241   }
242 
243   /// \brief Retrieve the attribute set node for the given "slot" in the
244   /// AttrNode list.
getSlotNode(unsigned Slot)245   AttributeSetNode *getSlotNode(unsigned Slot) const {
246     return getNode(Slot)->second;
247   }
248 
249   typedef AttributeSetNode::iterator iterator;
begin(unsigned Slot)250   iterator begin(unsigned Slot) const { return getSlotNode(Slot)->begin(); }
end(unsigned Slot)251   iterator end(unsigned Slot) const { return getSlotNode(Slot)->end(); }
252 
Profile(FoldingSetNodeID & ID)253   void Profile(FoldingSetNodeID &ID) const {
254     Profile(ID, makeArrayRef(getNode(0), getNumAttributes()));
255   }
Profile(FoldingSetNodeID & ID,ArrayRef<std::pair<unsigned,AttributeSetNode * >> Nodes)256   static void Profile(FoldingSetNodeID &ID,
257                       ArrayRef<std::pair<unsigned, AttributeSetNode*> > Nodes) {
258     for (unsigned i = 0, e = Nodes.size(); i != e; ++i) {
259       ID.AddInteger(Nodes[i].first);
260       ID.AddPointer(Nodes[i].second);
261     }
262   }
263 
264   // FIXME: This atrocity is temporary.
265   uint64_t Raw(unsigned Index) const;
266 
267   void dump() const;
268 };
269 
270 } // end llvm namespace
271 
272 #endif
273