1 //===-- Bitcode/Writer/ValueEnumerator.h - Number values --------*- 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 class gives values and types Unique ID's.
12 //===----------------------------------------------------------------------===//
14 #ifndef LLVM_LIB_BITCODE_WRITER_VALUEENUMERATOR_H
15 #define LLVM_LIB_BITCODE_WRITER_VALUEENUMERATOR_H
17 #include "llvm/ADT/DenseMap.h"
18 #include "llvm/ADT/UniqueVector.h"
19 #include "llvm/IR/Attributes.h"
20 #include "llvm/IR/Metadata.h"
21 #include "llvm/IR/Type.h"
22 #include "llvm/IR/UseListOrder.h"
35 class LocalAsMetadata;
40 class ValueSymbolTable;
44 class ValueEnumerator {
46 typedef std::vector<Type*> TypeList;
48 // For each value, we remember its Value* and occurrence frequency.
49 typedef std::vector<std::pair<const Value*, unsigned> > ValueList;
51 UseListOrderStack UseListOrders;
54 typedef DenseMap<Type*, unsigned> TypeMapType;
58 typedef DenseMap<const Value*, unsigned> ValueMapType;
59 ValueMapType ValueMap;
62 typedef UniqueVector<const Comdat *> ComdatSetType;
63 ComdatSetType Comdats;
65 std::vector<const Metadata *> MDs;
66 std::vector<const Metadata *> FunctionMDs;
68 /// Index of information about a piece of metadata.
70 unsigned F = 0; ///< The ID of the function for this metadata, if any.
71 unsigned ID = 0; ///< The implicit ID of this metadata in bitcode.
74 explicit MDIndex(unsigned F) : F(F) {}
76 /// Check if this has a function tag, and it's different from NewF.
77 bool hasDifferentFunction(unsigned NewF) const { return F && F != NewF; }
79 /// Fetch the MD this references out of the given metadata array.
80 const Metadata *get(ArrayRef<const Metadata *> MDs) const {
81 assert(ID && "Expected non-zero ID");
82 assert(ID <= MDs.size() && "Expected valid ID");
87 typedef DenseMap<const Metadata *, MDIndex> MetadataMapType;
88 MetadataMapType MetadataMap;
90 /// Range of metadata IDs, as a half-open range.
95 /// Number of strings in the prefix of the metadata range.
96 unsigned NumStrings = 0;
99 explicit MDRange(unsigned First) : First(First) {}
101 SmallDenseMap<unsigned, MDRange, 1> FunctionMDInfo;
103 bool ShouldPreserveUseListOrder;
105 typedef DenseMap<AttributeSet, unsigned> AttributeGroupMapType;
106 AttributeGroupMapType AttributeGroupMap;
107 std::vector<AttributeSet> AttributeGroups;
109 typedef DenseMap<AttributeSet, unsigned> AttributeMapType;
110 AttributeMapType AttributeMap;
111 std::vector<AttributeSet> Attribute;
113 /// GlobalBasicBlockIDs - This map memoizes the basic block ID's referenced by
114 /// the "getGlobalBasicBlockID" method.
115 mutable DenseMap<const BasicBlock*, unsigned> GlobalBasicBlockIDs;
117 typedef DenseMap<const Instruction*, unsigned> InstructionMapType;
118 InstructionMapType InstructionMap;
119 unsigned InstructionCount;
121 /// BasicBlocks - This contains all the basic blocks for the currently
122 /// incorporated function. Their reverse mapping is stored in ValueMap.
123 std::vector<const BasicBlock*> BasicBlocks;
125 /// When a function is incorporated, this is the size of the Values list
126 /// before incorporation.
127 unsigned NumModuleValues;
129 /// When a function is incorporated, this is the size of the Metadatas list
130 /// before incorporation.
131 unsigned NumModuleMDs = 0;
132 unsigned NumMDStrings = 0;
134 unsigned FirstFuncConstantID;
135 unsigned FirstInstID;
137 ValueEnumerator(const ValueEnumerator &) = delete;
138 void operator=(const ValueEnumerator &) = delete;
140 ValueEnumerator(const Module &M, bool ShouldPreserveUseListOrder);
143 void print(raw_ostream &OS, const ValueMapType &Map, const char *Name) const;
144 void print(raw_ostream &OS, const MetadataMapType &Map,
145 const char *Name) const;
147 unsigned getValueID(const Value *V) const;
148 unsigned getMetadataID(const Metadata *MD) const {
149 auto ID = getMetadataOrNullID(MD);
150 assert(ID != 0 && "Metadata not in slotcalculator!");
153 unsigned getMetadataOrNullID(const Metadata *MD) const {
154 return MetadataMap.lookup(MD).ID;
156 unsigned numMDs() const { return MDs.size(); }
158 bool shouldPreserveUseListOrder() const { return ShouldPreserveUseListOrder; }
160 unsigned getTypeID(Type *T) const {
161 TypeMapType::const_iterator I = TypeMap.find(T);
162 assert(I != TypeMap.end() && "Type not in ValueEnumerator!");
166 unsigned getInstructionID(const Instruction *I) const;
167 void setInstructionID(const Instruction *I);
169 unsigned getAttributeID(AttributeSet PAL) const {
170 if (PAL.isEmpty()) return 0; // Null maps to zero.
171 AttributeMapType::const_iterator I = AttributeMap.find(PAL);
172 assert(I != AttributeMap.end() && "Attribute not in ValueEnumerator!");
176 unsigned getAttributeGroupID(AttributeSet PAL) const {
177 if (PAL.isEmpty()) return 0; // Null maps to zero.
178 AttributeGroupMapType::const_iterator I = AttributeGroupMap.find(PAL);
179 assert(I != AttributeGroupMap.end() && "Attribute not in ValueEnumerator!");
183 /// getFunctionConstantRange - Return the range of values that corresponds to
184 /// function-local constants.
185 void getFunctionConstantRange(unsigned &Start, unsigned &End) const {
186 Start = FirstFuncConstantID;
190 const ValueList &getValues() const { return Values; }
192 /// Check whether the current block has any metadata to emit.
193 bool hasMDs() const { return NumModuleMDs < MDs.size(); }
195 /// Get the MDString metadata for this block.
196 ArrayRef<const Metadata *> getMDStrings() const {
197 return makeArrayRef(MDs).slice(NumModuleMDs, NumMDStrings);
200 /// Get the non-MDString metadata for this block.
201 ArrayRef<const Metadata *> getNonMDStrings() const {
202 return makeArrayRef(MDs).slice(NumModuleMDs).slice(NumMDStrings);
205 const TypeList &getTypes() const { return Types; }
206 const std::vector<const BasicBlock*> &getBasicBlocks() const {
209 const std::vector<AttributeSet> &getAttributes() const {
212 const std::vector<AttributeSet> &getAttributeGroups() const {
213 return AttributeGroups;
216 const ComdatSetType &getComdats() const { return Comdats; }
217 unsigned getComdatID(const Comdat *C) const;
219 /// getGlobalBasicBlockID - This returns the function-specific ID for the
220 /// specified basic block. This is relatively expensive information, so it
221 /// should only be used by rare constructs such as address-of-label.
222 unsigned getGlobalBasicBlockID(const BasicBlock *BB) const;
224 /// incorporateFunction/purgeFunction - If you'd like to deal with a function,
225 /// use these two methods to get its data into the ValueEnumerator!
227 void incorporateFunction(const Function &F);
228 void purgeFunction();
229 uint64_t computeBitsRequiredForTypeIndicies() const;
232 void OptimizeConstants(unsigned CstStart, unsigned CstEnd);
234 /// Reorder the reachable metadata.
236 /// This is not just an optimization, but is mandatory for emitting MDString
238 void organizeMetadata();
240 /// Drop the function tag from the transitive operands of the given node.
241 void dropFunctionFromMetadata(MetadataMapType::value_type &FirstMD);
243 /// Incorporate the function metadata.
245 /// This should be called before enumerating LocalAsMetadata for the
247 void incorporateFunctionMetadata(const Function &F);
249 /// Enumerate a single instance of metadata with the given function tag.
251 /// If \c MD has already been enumerated, check that \c F matches its
252 /// function tag. If not, call \a dropFunctionFromMetadata().
254 /// Otherwise, mark \c MD as visited. Assign it an ID, or just return it if
255 /// it's an \a MDNode.
256 const MDNode *enumerateMetadataImpl(unsigned F, const Metadata *MD);
258 unsigned getMetadataFunctionID(const Function *F) const;
260 /// Enumerate reachable metadata in (almost) post-order.
262 /// Enumerate all the metadata reachable from MD. We want to minimize the
263 /// cost of reading bitcode records, and so the primary consideration is that
264 /// operands of uniqued nodes are resolved before the nodes are read. This
265 /// avoids re-uniquing them on the context and factors away RAUW support.
267 /// This algorithm guarantees that subgraphs of uniqued nodes are in
268 /// post-order. Distinct subgraphs reachable only from a single uniqued node
269 /// will be in post-order.
271 /// \note The relative order of a distinct and uniqued node is irrelevant.
272 /// \a organizeMetadata() will later partition distinct nodes ahead of
275 void EnumerateMetadata(const Function *F, const Metadata *MD);
276 void EnumerateMetadata(unsigned F, const Metadata *MD);
279 void EnumerateFunctionLocalMetadata(const Function &F,
280 const LocalAsMetadata *Local);
281 void EnumerateFunctionLocalMetadata(unsigned F, const LocalAsMetadata *Local);
282 void EnumerateNamedMDNode(const NamedMDNode *NMD);
283 void EnumerateValue(const Value *V);
284 void EnumerateType(Type *T);
285 void EnumerateOperandType(const Value *V);
286 void EnumerateAttributes(AttributeSet PAL);
288 void EnumerateValueSymbolTable(const ValueSymbolTable &ST);
289 void EnumerateNamedMetadata(const Module &M);
292 } // End llvm namespace