llvm-6502/include/llvm/Bitcode/Deserialize.h
Ted Kremenek 5973ef40ca Updated backpatching logic during object deserialization to perform
eager backpatching instead of waithing until all objects have been
deserialized.  This allows us to reduce the memory footprint needed
for backpatching.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@43422 91177308-0d34-0410-b5e6-96231b3b80d8
2007-10-28 21:17:59 +00:00

151 lines
3.9 KiB
C++

//=- Deserialize.h - Generic Object Deserialization from Bitcode --*- C++ -*-=//
//
// The LLVM Compiler Infrastructure
//
// This file was developed by Ted Kremenek and is distributed under the
// University of Illinois Open Source License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file defines the interface for generic object deserialization from
// LLVM bitcode.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_BITCODE_SERIALIZE_INPUT
#define LLVM_BITCODE_SERIALIZE_INPUT
#include "llvm/Bitcode/BitstreamReader.h"
#include "llvm/Bitcode/Serialization.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/Support/Allocator.h"
#include "llvm/Support/DataTypes.h"
#include <vector>
namespace llvm {
class Deserializer {
//===----------------------------------------------------------===//
// Internal type definitions.
//===----------------------------------------------------------===//
struct PtrIdInfo {
static inline unsigned getEmptyKey() { return ~((unsigned) 0x0); }
static inline unsigned getTombstoneKey() { return getEmptyKey()-1; }
static inline unsigned getHashValue(unsigned X) { return X; }
static inline bool isEqual(unsigned X, unsigned Y) { return X == Y; }
static inline bool isPod() { return true; }
};
struct BPNode {
BPNode* Next;
uintptr_t& PtrRef;
BPNode(BPNode* n, uintptr_t& pref)
: Next(n), PtrRef(pref) {
PtrRef = 0;
}
};
class BPatchEntry {
uintptr_t Ptr;
public:
BPatchEntry() : Ptr(0x1) {}
BPatchEntry(void* P) : Ptr(reinterpret_cast<uintptr_t>(P)) {}
bool hasFinalPtr() const { return Ptr & 0x1 ? true : false; }
void setFinalPtr(BPNode*& FreeList, void* P);
BPNode* getBPNode() const {
assert (!hasFinalPtr());
return reinterpret_cast<BPNode*>(Ptr & ~0x1);
}
void setBPNode(BPNode* N) {
assert (!hasFinalPtr());
Ptr = reinterpret_cast<uintptr_t>(N) | 0x1;
}
uintptr_t getRawPtr() const { return Ptr; }
static inline bool isPod() { return true; }
};
typedef llvm::DenseMap<unsigned,BPatchEntry,PtrIdInfo,BPatchEntry> MapTy;
//===----------------------------------------------------------===//
// Internal data members.
//===----------------------------------------------------------===//
BitstreamReader& Stream;
SmallVector<uint64_t,10> Record;
unsigned RecIdx;
BumpPtrAllocator Allocator;
BPNode* FreeList;
MapTy BPatchMap;
//===----------------------------------------------------------===//
// Public Interface.
//===----------------------------------------------------------===//
public:
Deserializer(BitstreamReader& stream);
~Deserializer();
uint64_t ReadInt();
bool ReadBool() {
return ReadInt() ? true : false;
}
template <typename T>
inline T& Read(T& X) {
SerializeTrait<T>::Read(*this,X);
return X;
}
template <typename T>
inline T ReadVal() {
return SerializeTrait<T>::ReadVal(*this);
}
template <typename T>
inline T* Materialize() {
return SerializeTrait<T>::Materialize(*this);
}
char* ReadCStr(char* cstr = NULL, unsigned MaxLen=0, bool isNullTerm=true);
void ReadCStr(std::vector<char>& buff, bool isNullTerm=false);
template <typename T>
inline T* ReadOwnedPtr() {
unsigned PtrId = ReadInt();
if (PtrId == 0)
return NULL;
T* x = SerializeTrait<T>::Materialize(*this);
RegisterPtr(PtrId,x);
return x;
}
template <typename T>
void ReadPtr(T*& PtrRef) { ReadUIntPtr(reinterpret_cast<uintptr_t&>(PtrRef));}
void ReadPtr(uintptr_t& PtrRef) { ReadUIntPtr(PtrRef); }
void ReadUIntPtr(uintptr_t& PtrRef);
void RegisterPtr(unsigned PtrId, void* Ptr);
private:
void ReadRecord();
bool inRecord();
};
} // end namespace llvm
#endif