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 "llvm/Constants.h"
18 #include "llvm/DerivedTypes.h"
19 #include "llvm/Function.h"
20 #include "llvm/ModuleProvider.h"
21 #include "llvm/Bytecode/Primitives.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 unsigned FunctionSlot;
43 class BytecodeParser : public ModuleProvider {
44 BytecodeParser(const BytecodeParser &); // DO NOT IMPLEMENT
45 void operator=(const BytecodeParser &); // DO NOT IMPLEMENT
48 // Define this in case we don't see a ModuleGlobalInfo block.
49 FirstDerivedTyID = Type::FirstDerivedTyID;
57 freeTable(ModuleValues);
60 Module* releaseModule() {
61 // Since we're losing control of this Module, we must hand it back complete
62 Module *M = ModuleProvider::releaseModule();
67 void ParseBytecode(const unsigned char *Buf, unsigned Length,
68 const std::string &ModuleID);
71 std::cerr << "BytecodeParser instance!\n";
75 struct ValueList : public User {
76 ValueList() : User(Type::TypeTy, Value::TypeVal) {}
78 // vector compatibility methods
79 unsigned size() const { return getNumOperands(); }
80 void push_back(Value *V) { Operands.push_back(Use(V, this)); }
81 Value *back() const { return Operands.back(); }
82 void pop_back() { Operands.pop_back(); }
83 bool empty() const { return Operands.empty(); }
85 virtual void print(std::ostream& OS) const {
86 OS << "Bytecode Reader UseHandle!";
90 // Information about the module, extracted from the bytecode revision number.
91 unsigned char RevisionNum; // The rev # itself
92 unsigned char FirstDerivedTyID; // First variable index to use for type
93 bool hasInternalMarkerOnly; // Only types of linkage are intern/external
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 typedef std::vector<ValueList*> ValueTable;
102 ValueTable ModuleValues;
103 std::map<std::pair<unsigned,unsigned>, Value*> ForwardReferences;
105 std::vector<BasicBlock*> ParsedBasicBlocks;
107 // GlobalRefs - This maintains a mapping between <Type, Slot #>'s and forward
108 // references to global values or constants. Such values may be referenced
109 // before they are defined, and if so, the temporary object that they
110 // represent is held here.
112 typedef std::map<std::pair<const Type *, unsigned>, Value*> GlobalRefsType;
113 GlobalRefsType GlobalRefs;
115 // TypesLoaded - This vector mirrors the Values[TypeTyID] plane. It is used
116 // to deal with forward references to types.
118 typedef std::vector<PATypeHolder> TypeValuesListTy;
119 TypeValuesListTy ModuleTypeValues;
120 TypeValuesListTy FunctionTypeValues;
122 // When the ModuleGlobalInfo section is read, we create a function object for
123 // each function in the module. When the function is loaded, this function is
126 std::vector<std::pair<Function*, unsigned> > FunctionSignatureList;
128 // Constant values are read in after global variables. Because of this, we
129 // must defer setting the initializers on global variables until after module
130 // level constants have been read. In the mean time, this list keeps track of
133 std::vector<std::pair<GlobalVariable*, unsigned> > GlobalInits;
135 // For lazy reading-in of functions, we need to save away several pieces of
136 // information about each function: its begin and end pointer in the buffer
137 // and its FunctionSlot.
139 std::map<Function*, LazyFunctionInfo*> LazyFunctionLoadMap;
142 void freeTable(ValueTable &Tab) {
143 while (!Tab.empty()) {
150 void ParseModule(const unsigned char * Buf, const unsigned char *End);
151 void materializeFunction(Function *F);
154 void ParseVersionInfo (const unsigned char *&Buf, const unsigned char *End);
155 void ParseModuleGlobalInfo(const unsigned char *&Buf, const unsigned char *E);
156 void ParseSymbolTable(const unsigned char *&Buf, const unsigned char *End,
157 SymbolTable *, Function *CurrentFunction);
158 void ParseFunction(const unsigned char *&Buf, const unsigned char *End);
159 void ParseGlobalTypes(const unsigned char *&Buf, const unsigned char *EndBuf);
161 BasicBlock *ParseBasicBlock(const unsigned char *&Buf,
162 const unsigned char *End,
165 void ParseInstruction(const unsigned char *&Buf, const unsigned char *End,
166 std::vector<unsigned> &Args, BasicBlock *BB);
168 void ParseConstantPool(const unsigned char *&Buf, const unsigned char *EndBuf,
169 ValueTable &Tab, TypeValuesListTy &TypeTab);
170 Constant *parseConstantValue(const unsigned char *&Buf,
171 const unsigned char *End,
173 void parseTypeConstants(const unsigned char *&Buf,
174 const unsigned char *EndBuf,
175 TypeValuesListTy &Tab, unsigned NumEntries);
176 const Type *parseTypeConstant(const unsigned char *&Buf,
177 const unsigned char *EndBuf);
179 Value *getValue(const Type *Ty, unsigned num, bool Create = true);
180 Value *getValue(unsigned TypeID, unsigned num, bool Create = true);
181 const Type *getType(unsigned ID);
182 BasicBlock *getBasicBlock(unsigned ID);
183 Constant *getConstantValue(unsigned TypeID, unsigned num);
184 Constant *getConstantValue(const Type *Ty, unsigned num) {
185 return getConstantValue(getTypeSlot(Ty), num);
188 unsigned insertValue(Value *V, ValueTable &Table);
189 unsigned insertValue(Value *V, unsigned Type, ValueTable &Table);
191 unsigned getTypeSlot(const Type *Ty);
193 // resolve all references to the placeholder (if any) for the given value
194 void ResolveReferencesToValue(Value *Val, unsigned Slot);
197 template<class SuperType>
198 class PlaceholderDef : public SuperType {
200 PlaceholderDef(); // DO NOT IMPLEMENT
201 void operator=(const PlaceholderDef &); // DO NOT IMPLEMENT
203 PlaceholderDef(const Type *Ty, unsigned id) : SuperType(Ty), ID(id) {}
204 unsigned getID() { return ID; }
207 struct ConstantPlaceHolderHelper : public ConstantExpr {
208 ConstantPlaceHolderHelper(const Type *Ty)
209 : ConstantExpr(Instruction::UserOp1, Constant::getNullValue(Ty), Ty) {}
212 typedef PlaceholderDef<ConstantPlaceHolderHelper> ConstPHolder;
214 // Some common errors we find
215 static const std::string Error_readvbr = "read_vbr(): error reading.";
216 static const std::string Error_read = "read(): error reading.";
217 static const std::string Error_inputdata = "input_data(): error reading.";
218 static const std::string Error_DestSlot = "No destination slot found.";
220 static inline void readBlock(const unsigned char *&Buf,
221 const unsigned char *EndBuf,
222 unsigned &Type, unsigned &Size) {
224 bool Result = read(Buf, EndBuf, Type) || read(Buf, EndBuf, Size);
225 std::cerr << "StartLoc = " << ((unsigned)Buf & 4095)
226 << " Type = " << Type << " Size = " << Size << "\n";
227 if (Result) throw Error_read;
229 if (read(Buf, EndBuf, Type) || read(Buf, EndBuf, Size)) throw Error_read;
233 } // End llvm namespace