llvm-6502/lib/Bytecode/Reader/ReaderInternals.h
Chris Lattner bbd4b303e3 There is no way to guarantee that constants are not forward referenced.
Handle forward referenced constants in a general way.  This fixes bug:
Assembler/2002-10-13-ConstantEncodingProblem.llx and allows the SPEC
197.parser benchmark to be built


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@4161 91177308-0d34-0410-b5e6-96231b3b80d8
2002-10-14 03:33:02 +00:00

194 lines
6.8 KiB
C++

//===-- ReaderInternals.h - Definitions internal to the reader ---*- C++ -*--=//
//
// This header file defines various stuff that is used by the bytecode reader.
//
//===----------------------------------------------------------------------===//
#ifndef READER_INTERNALS_H
#define READER_INTERNALS_H
#include "llvm/Bytecode/Primitives.h"
#include "llvm/DerivedTypes.h"
#include "llvm/Function.h"
#include "llvm/Constant.h"
#include <utility>
#include <map>
// Enable to trace to figure out what the heck is going on when parsing fails
#define TRACE_LEVEL 0
#if TRACE_LEVEL // ByteCodeReading_TRACEer
#define BCR_TRACE(n, X) if (n < TRACE_LEVEL) std::cerr << std::string(n*2, ' ') << X
#else
#define BCR_TRACE(n, X)
#endif
typedef unsigned char uchar;
struct RawInst { // The raw fields out of the bytecode stream...
unsigned NumOperands;
unsigned Opcode;
const Type *Ty;
unsigned Arg1, Arg2;
union {
unsigned Arg3;
std::vector<unsigned> *VarArgs; // Contains arg #3,4,5... if NumOperands > 3
};
};
class BytecodeParser : public AbstractTypeUser {
std::string Error; // Error message string goes here...
BytecodeParser(const BytecodeParser &); // DO NOT IMPLEMENT
void operator=(const BytecodeParser &); // DO NOT IMPLEMENT
public:
BytecodeParser() {
// Define this in case we don't see a ModuleGlobalInfo block.
FirstDerivedTyID = Type::FirstDerivedTyID;
}
Module *ParseBytecode(const uchar *Buf, const uchar *EndBuf);
std::string getError() const { return Error; }
void dump() const {
std::cerr << "BytecodeParser instance!\n";
}
private: // All of this data is transient across calls to ParseBytecode
Module *TheModule; // Current Module being read into...
typedef std::vector<Value *> ValueList;
typedef std::vector<ValueList> ValueTable;
ValueTable Values, LateResolveValues;
ValueTable ModuleValues, LateResolveModuleValues;
// GlobalRefs - This maintains a mapping between <Type, Slot #>'s and forward
// references to global values or constants. Such values may be referenced
// before they are defined, and if so, the temporary object that they
// represent is held here.
//
typedef std::map<std::pair<const Type *, unsigned>,
Value*> GlobalRefsType;
GlobalRefsType GlobalRefs;
// TypesLoaded - This vector mirrors the Values[TypeTyID] plane. It is used
// to deal with forward references to types.
//
typedef std::vector<PATypeHandle<Type> > TypeValuesListTy;
TypeValuesListTy ModuleTypeValues;
TypeValuesListTy MethodTypeValues;
// Information read from the ModuleGlobalInfo section of the file...
unsigned FirstDerivedTyID;
// When the ModuleGlobalInfo section is read, we load the type of each
// function and the 'ModuleValues' slot that it lands in. We then load a
// placeholder into its slot to reserve it. When the function is loaded, this
// placeholder is replaced.
//
std::vector<std::pair<const PointerType *, unsigned> > FunctionSignatureList;
private:
bool ParseModule (const uchar * Buf, const uchar *End, Module *&);
bool ParseModuleGlobalInfo(const uchar *&Buf, const uchar *End, Module *);
bool ParseSymbolTable (const uchar *&Buf, const uchar *End, SymbolTable *);
bool ParseMethod (const uchar *&Buf, const uchar *End, Module *);
bool ParseBasicBlock (const uchar *&Buf, const uchar *End, BasicBlock *&);
bool ParseInstruction (const uchar *&Buf, const uchar *End, Instruction *&,
BasicBlock *BB /*HACK*/);
bool ParseRawInst (const uchar *&Buf, const uchar *End, RawInst &);
bool ParseConstantPool(const uchar *&Buf, const uchar *EndBuf,
ValueTable &Tab, TypeValuesListTy &TypeTab);
bool parseConstantValue(const uchar *&Buf, const uchar *End,
const Type *Ty, Constant *&V);
bool parseTypeConstants(const uchar *&Buf, const uchar *EndBuf,
TypeValuesListTy &Tab, unsigned NumEntries);
const Type *parseTypeConstant(const uchar *&Buf, const uchar *EndBuf);
Value *getValue(const Type *Ty, unsigned num, bool Create = true);
const Type *getType(unsigned ID);
Constant *getConstantValue(const Type *Ty, unsigned num);
int insertValue(Value *D, std::vector<ValueList> &D); // -1 = Failure
bool postResolveValues(ValueTable &ValTab);
bool getTypeSlot(const Type *Ty, unsigned &Slot);
// resolve all references to the placeholder (if any) for the given value
void ResolveReferencesToValue(Value *Val, unsigned Slot);
// refineAbstractType - The callback method is invoked when one of the
// elements of TypeValues becomes more concrete...
//
virtual void refineAbstractType(const DerivedType *OldTy, const Type *NewTy);
};
template<class SuperType>
class PlaceholderDef : public SuperType {
unsigned ID;
PlaceholderDef(); // DO NOT IMPLEMENT
void operator=(const PlaceholderDef &); // DO NOT IMPLEMENT
public:
PlaceholderDef(const Type *Ty, unsigned id) : SuperType(Ty), ID(id) {}
unsigned getID() { return ID; }
};
struct InstPlaceHolderHelper : public Instruction {
InstPlaceHolderHelper(const Type *Ty) : Instruction(Ty, UserOp1, "") {}
virtual const char *getOpcodeName() const { return "placeholder"; }
virtual Instruction *clone() const { abort(); return 0; }
};
struct BBPlaceHolderHelper : public BasicBlock {
BBPlaceHolderHelper(const Type *Ty) : BasicBlock() {
assert(Ty == Type::LabelTy);
}
};
struct FunctionPlaceHolderHelper : public Function {
FunctionPlaceHolderHelper(const Type *Ty)
: Function(cast<const FunctionType>(Ty), true) {
}
};
struct ConstantPlaceHolderHelper : public Constant {
ConstantPlaceHolderHelper(const Type *Ty)
: Constant(Ty) {}
virtual bool isNullValue() const { return false; }
};
typedef PlaceholderDef<InstPlaceHolderHelper> ValPHolder;
typedef PlaceholderDef<BBPlaceHolderHelper> BBPHolder;
typedef PlaceholderDef<FunctionPlaceHolderHelper> FunctionPHolder;
typedef PlaceholderDef<ConstantPlaceHolderHelper> ConstPHolder;
static inline unsigned getValueIDNumberFromPlaceHolder(Value *Val) {
if (isa<Constant>(Val))
return ((ConstPHolder*)Val)->getID();
// else discriminate by type
switch (Val->getType()->getPrimitiveID()) {
case Type::LabelTyID: return ((BBPHolder*)Val)->getID();
case Type::FunctionTyID: return ((FunctionPHolder*)Val)->getID();
default: return ((ValPHolder*)Val)->getID();
}
}
static inline bool readBlock(const uchar *&Buf, const uchar *EndBuf,
unsigned &Type, unsigned &Size) {
#if DEBUG_OUTPUT
bool Result = read(Buf, EndBuf, Type) || read(Buf, EndBuf, Size);
std::cerr << "StartLoc = " << ((unsigned)Buf & 4095)
<< " Type = " << Type << " Size = " << Size << endl;
return Result;
#else
return read(Buf, EndBuf, Type) || read(Buf, EndBuf, Size);
#endif
}
#endif