MCObjectSymbolizer.h revision 263508
1//===-- llvm/MC/MCObjectSymbolizer.h --------------------------------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file declares the MCObjectSymbolizer class, an MCSymbolizer that is 11// backed by an object::ObjectFile. 12// 13//===----------------------------------------------------------------------===// 14 15#ifndef LLVM_MC_MCOBJECTSYMBOLIZER_H 16#define LLVM_MC_MCOBJECTSYMBOLIZER_H 17 18#include "llvm/ADT/DenseMap.h" 19#include "llvm/MC/MCSymbolizer.h" 20#include "llvm/Object/ObjectFile.h" 21#include <vector> 22 23namespace llvm { 24 25class MCExpr; 26class MCInst; 27class MCRelocationInfo; 28class raw_ostream; 29 30/// \brief An ObjectFile-backed symbolizer. 31class MCObjectSymbolizer : public MCSymbolizer { 32protected: 33 const object::ObjectFile *Obj; 34 35 // Map a load address to the first relocation that applies there. As far as I 36 // know, if there are several relocations at the exact same address, they are 37 // related and the others can be determined from the first that was found in 38 // the relocation table. For instance, on x86-64 mach-o, a SUBTRACTOR 39 // relocation (referencing the minuend symbol) is followed by an UNSIGNED 40 // relocation (referencing the subtrahend symbol). 41 const object::RelocationRef *findRelocationAt(uint64_t Addr); 42 const object::SectionRef *findSectionContaining(uint64_t Addr); 43 44 MCObjectSymbolizer(MCContext &Ctx, OwningPtr<MCRelocationInfo> &RelInfo, 45 const object::ObjectFile *Obj); 46 47public: 48 /// \name Overridden MCSymbolizer methods: 49 /// @{ 50 bool tryAddingSymbolicOperand(MCInst &MI, raw_ostream &cStream, 51 int64_t Value, uint64_t Address, 52 bool IsBranch, uint64_t Offset, 53 uint64_t InstSize); 54 55 void tryAddingPcLoadReferenceComment(raw_ostream &cStream, 56 int64_t Value, uint64_t Address); 57 /// @} 58 59 /// \brief Look for an external function symbol at \p Addr. 60 /// (References through the ELF PLT, Mach-O stubs, and similar). 61 /// \returns An MCExpr representing the external symbol, or 0 if not found. 62 virtual StringRef findExternalFunctionAt(uint64_t Addr); 63 64 /// \brief Create an object symbolizer for \p Obj. 65 static MCObjectSymbolizer * 66 createObjectSymbolizer(MCContext &Ctx, OwningPtr<MCRelocationInfo> &RelInfo, 67 const object::ObjectFile *Obj); 68 69private: 70 typedef DenseMap<uint64_t, object::RelocationRef> AddrToRelocMap; 71 typedef std::vector<object::SectionRef> SortedSectionList; 72 SortedSectionList SortedSections; 73 AddrToRelocMap AddrToReloc; 74 75 void buildSectionList(); 76 void buildRelocationByAddrMap(); 77}; 78 79} 80 81#endif 82