llvm/lib/Bitcode/Reader/BitcodeReader.h
Chris Lattner c453f76e2b Switch the bitcode reader interface to take a MemoryBuffer instead of knowing
anything about disk I/O itself.  This greatly simplifies its interface -
eliminating the need for the ReaderWrappers.cpp file.

This adds a new option to llvm-dis (-bitcode) which instructs it to read
the input file as bitcode.  Until/unless the bytecode reader is taught to
read from MemoryBuffer, there is no way to handle stdin reading without it.

I don't plan to switch the bytecode reader over, I'd rather delete it :),
so the option will stay around temporarily.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@36554 91177308-0d34-0410-b5e6-96231b3b80d8
2007-04-29 07:54:31 +00:00

115 lines
3.3 KiB
C++

//===- BitcodeReader.h - Internal BitcodeReader impl ------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file was developed by Chris Lattner and is distributed under
// the University of Illinois Open Source License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This header defines the BitcodeReader class.
//
//===----------------------------------------------------------------------===//
#ifndef BITCODE_READER_H
#define BITCODE_READER_H
#include "llvm/ModuleProvider.h"
#include "llvm/Type.h"
#include "llvm/User.h"
#include "llvm/Bitcode/LLVMBitCodes.h"
#include <vector>
namespace llvm {
class BitstreamReader;
class MemoryBuffer;
class BitcodeReaderValueList : public User {
std::vector<Use> Uses;
public:
BitcodeReaderValueList() : User(Type::VoidTy, Value::ArgumentVal, 0, 0) {}
// vector compatibility methods
unsigned size() const { return getNumOperands(); }
void push_back(Value *V) {
Uses.push_back(Use(V, this));
OperandList = &Uses[0];
++NumOperands;
}
Value *operator[](unsigned i) const { return getOperand(i); }
Value *back() const { return Uses.back(); }
void pop_back() { Uses.pop_back(); --NumOperands; }
bool empty() const { return NumOperands == 0; }
void shrinkTo(unsigned N) {
assert(N < NumOperands && "Invalid shrinkTo request!");
Uses.resize(N);
NumOperands = N;
}
virtual void print(std::ostream&) const {}
Constant *getConstantFwdRef(unsigned Idx, const Type *Ty);
void initVal(unsigned Idx, Value *V) {
assert(Uses[Idx] == 0 && "Cannot init an already init'd Use!");
Uses[Idx].init(V, this);
}
};
class BitcodeReader : public ModuleProvider {
MemoryBuffer *Buffer;
const char *ErrorString;
std::vector<PATypeHolder> TypeList;
BitcodeReaderValueList ValueList;
std::vector<std::pair<GlobalVariable*, unsigned> > GlobalInits;
std::vector<std::pair<GlobalAlias*, unsigned> > AliasInits;
public:
BitcodeReader(MemoryBuffer *buffer) : Buffer(buffer), ErrorString(0) {}
~BitcodeReader();
/// releaseMemoryBuffer - This causes the reader to completely forget about
/// the memory buffer it contains, which prevents the buffer from being
/// destroyed when it is deleted.
void releaseMemoryBuffer() {
Buffer = 0;
}
virtual bool materializeFunction(Function *F, std::string *ErrInfo = 0) {
// FIXME: TODO
return false;
}
virtual Module *materializeModule(std::string *ErrInfo = 0) {
// FIXME: TODO
//if (ParseAllFunctionBodies(ErrMsg))
// return 0;
return TheModule;
}
bool Error(const char *Str) {
ErrorString = Str;
return true;
}
const char *getErrorString() const { return ErrorString; }
/// @brief Main interface to parsing a bitcode buffer.
/// @returns true if an error occurred.
bool ParseBitcode();
private:
const Type *getTypeByID(unsigned ID, bool isTypeTable = false);
bool ParseModule(BitstreamReader &Stream, const std::string &ModuleID);
bool ParseTypeTable(BitstreamReader &Stream);
bool ParseTypeSymbolTable(BitstreamReader &Stream);
bool ParseValueSymbolTable(BitstreamReader &Stream);
bool ParseConstants(BitstreamReader &Stream);
bool ResolveGlobalAndAliasInits();
};
} // End llvm namespace
#endif