1 //===-- ReaderInternals.h - Definitions internal to the reader --*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file was developed by the LLVM research group and is distributed under
6 // the University of Illinois Open Source License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This header file defines various stuff that is used by the bytecode reader.
12 //===----------------------------------------------------------------------===//
14 #ifndef READER_INTERNALS_H
15 #define READER_INTERNALS_H
17 #include "ReaderPrimitives.h"
18 #include "llvm/Constants.h"
19 #include "llvm/DerivedTypes.h"
20 #include "llvm/Function.h"
21 #include "llvm/ModuleProvider.h"
27 // Enable to trace to figure out what the heck is going on when parsing fails
28 //#define TRACE_LEVEL 10
29 //#define DEBUG_OUTPUT
31 #if TRACE_LEVEL // ByteCodeReading_TRACEr
32 #define BCR_TRACE(n, X) \
33 if (n < TRACE_LEVEL) std::cerr << std::string(n*2, ' ') << X
35 #define BCR_TRACE(n, X)
38 struct LazyFunctionInfo {
39 const unsigned char *Buf, *EndBuf;
40 LazyFunctionInfo(const unsigned char *B = 0, const unsigned char *EB = 0)
41 : Buf(B), EndBuf(EB) {}
44 class BytecodeParser : public ModuleProvider {
45 BytecodeParser(const BytecodeParser &); // DO NOT IMPLEMENT
46 void operator=(const BytecodeParser &); // DO NOT IMPLEMENT
49 // Define this in case we don't see a ModuleGlobalInfo block.
50 FirstDerivedTyID = Type::FirstDerivedTyID;
58 freeTable(ModuleValues);
61 Module* releaseModule() {
62 // Since we're losing control of this Module, we must hand it back complete
63 Module *M = ModuleProvider::releaseModule();
68 void ParseBytecode(const unsigned char *Buf, unsigned Length,
69 const std::string &ModuleID);
72 std::cerr << "BytecodeParser instance!\n";
76 struct ValueList : public User {
77 ValueList() : User(Type::TypeTy, Value::TypeVal) {}
79 // vector compatibility methods
80 unsigned size() const { return getNumOperands(); }
81 void push_back(Value *V) { Operands.push_back(Use(V, this)); }
82 Value *back() const { return Operands.back(); }
83 void pop_back() { Operands.pop_back(); }
84 bool empty() const { return Operands.empty(); }
86 virtual void print(std::ostream& OS) const {
87 OS << "Bytecode Reader UseHandle!";
91 // Information about the module, extracted from the bytecode revision number.
92 unsigned char RevisionNum; // The rev # itself
93 unsigned char FirstDerivedTyID; // First variable index to use for type
94 bool hasExtendedLinkageSpecs; // Supports more than 4 linkage types
95 bool hasOldStyleVarargs; // Has old version of varargs intrinsics?
96 bool hasVarArgCallPadding; // Bytecode has extra padding in vararg call
98 bool usesOldStyleVarargs; // Does this module USE old style varargs?
100 // Flags to distinguish LLVM 1.0 & 1.1 bytecode formats (revision #0)
102 // Revision #0 had an explicit alignment of data only for the ModuleGlobalInfo
103 // block. This was fixed to be like all other blocks in 1.2
104 bool hasInconsistentModuleGlobalInfo;
106 // Revision #0 also explicitly encoded zero values for primitive types like
108 bool hasExplicitPrimitiveZeros;
110 typedef std::vector<ValueList*> ValueTable;
112 ValueTable ModuleValues;
113 std::map<std::pair<unsigned,unsigned>, Value*> ForwardReferences;
115 std::vector<BasicBlock*> ParsedBasicBlocks;
117 // ConstantFwdRefs - This maintains a mapping between <Type, Slot #>'s and
118 // forward references to constants. Such values may be referenced before they
119 // are defined, and if so, the temporary object that they represent is held
122 typedef std::map<std::pair<const Type*,unsigned>, Constant*> ConstantRefsType;
123 ConstantRefsType ConstantFwdRefs;
125 // TypesLoaded - This vector mirrors the Values[TypeTyID] plane. It is used
126 // to deal with forward references to types.
128 typedef std::vector<PATypeHolder> TypeValuesListTy;
129 TypeValuesListTy ModuleTypeValues;
130 TypeValuesListTy FunctionTypeValues;
132 // When the ModuleGlobalInfo section is read, we create a function object for
133 // each function in the module. When the function is loaded, this function is
136 std::vector<Function*> FunctionSignatureList;
138 // Constant values are read in after global variables. Because of this, we
139 // must defer setting the initializers on global variables until after module
140 // level constants have been read. In the mean time, this list keeps track of
143 std::vector<std::pair<GlobalVariable*, unsigned> > GlobalInits;
145 // For lazy reading-in of functions, we need to save away several pieces of
146 // information about each function: its begin and end pointer in the buffer
147 // and its FunctionSlot.
149 std::map<Function*, LazyFunctionInfo> LazyFunctionLoadMap;
152 void freeTable(ValueTable &Tab) {
153 while (!Tab.empty()) {
160 void ParseModule(const unsigned char * Buf, const unsigned char *End);
161 void materializeFunction(Function *F);
164 void ParseVersionInfo (const unsigned char *&Buf, const unsigned char *End);
165 void ParseModuleGlobalInfo(const unsigned char *&Buf, const unsigned char *E);
166 void ParseSymbolTable(const unsigned char *&Buf, const unsigned char *End,
167 SymbolTable *, Function *CurrentFunction);
168 void ParseFunction(const unsigned char *&Buf, const unsigned char *End);
169 void ParseGlobalTypes(const unsigned char *&Buf, const unsigned char *EndBuf);
171 BasicBlock *ParseBasicBlock(const unsigned char *&Buf,
172 const unsigned char *End,
174 unsigned ParseInstructionList(Function *F, const unsigned char *&Buf,
175 const unsigned char *EndBuf);
177 void ParseInstruction(const unsigned char *&Buf, const unsigned char *End,
178 std::vector<unsigned> &Args, BasicBlock *BB);
180 void ParseConstantPool(const unsigned char *&Buf, const unsigned char *EndBuf,
181 ValueTable &Tab, TypeValuesListTy &TypeTab);
182 Constant *parseConstantValue(const unsigned char *&Buf,
183 const unsigned char *End,
185 void parseTypeConstants(const unsigned char *&Buf,
186 const unsigned char *EndBuf,
187 TypeValuesListTy &Tab, unsigned NumEntries);
188 const Type *parseTypeConstant(const unsigned char *&Buf,
189 const unsigned char *EndBuf);
190 void parseStringConstants(const unsigned char *&Buf,
191 const unsigned char *EndBuf,
192 unsigned NumEntries, ValueTable &Tab);
194 Value *getValue(unsigned TypeID, unsigned num, bool Create = true);
195 const Type *getType(unsigned ID);
196 BasicBlock *getBasicBlock(unsigned ID);
197 Constant *getConstantValue(unsigned TypeID, unsigned num);
198 Constant *getConstantValue(const Type *Ty, unsigned num) {
199 return getConstantValue(getTypeSlot(Ty), num);
202 unsigned insertValue(Value *V, unsigned Type, ValueTable &Table);
204 unsigned getTypeSlot(const Type *Ty);
206 // resolve all references to the placeholder (if any) for the given constant
207 void ResolveReferencesToConstant(Constant *C, unsigned Slot);
210 template<class SuperType>
211 class PlaceholderDef : public SuperType {
213 PlaceholderDef(); // DO NOT IMPLEMENT
214 void operator=(const PlaceholderDef &); // DO NOT IMPLEMENT
216 PlaceholderDef(const Type *Ty, unsigned id) : SuperType(Ty), ID(id) {}
217 unsigned getID() { return ID; }
220 struct ConstantPlaceHolderHelper : public ConstantExpr {
221 ConstantPlaceHolderHelper(const Type *Ty)
222 : ConstantExpr(Instruction::UserOp1, Constant::getNullValue(Ty), Ty) {}
225 typedef PlaceholderDef<ConstantPlaceHolderHelper> ConstPHolder;
227 static inline void readBlock(const unsigned char *&Buf,
228 const unsigned char *EndBuf,
229 unsigned &Type, unsigned &Size) {
230 Type = read(Buf, EndBuf);
231 Size = read(Buf, EndBuf);
234 } // End llvm namespace