1 //===- DWARFDataExtractor.h -------------------------------------*- C++ -*-===// 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 #ifndef LLVM_DEBUGINFO_DWARFDATAEXTRACTOR_H 11 #define LLVM_DEBUGINFO_DWARFDATAEXTRACTOR_H 12 13 #include "llvm/DebugInfo/DWARF/DWARFSection.h" 14 #include "llvm/Support/DataExtractor.h" 15 16 namespace llvm { 17 class DWARFObject; 18 19 /// A DataExtractor (typically for an in-memory copy of an object-file section) 20 /// plus a relocation map for that section, if there is one. 21 class DWARFDataExtractor : public DataExtractor { 22 const DWARFObject *Obj = nullptr; 23 const DWARFSection *Section = nullptr; 24 25 public: 26 /// Constructor for the normal case of extracting data from a DWARF section. 27 /// The DWARFSection's lifetime must be at least as long as the extractor's. 28 DWARFDataExtractor(const DWARFObject &Obj, const DWARFSection &Section, 29 bool IsLittleEndian, uint8_t AddressSize) 30 : DataExtractor(Section.Data, IsLittleEndian, AddressSize), Obj(&Obj), 31 Section(&Section) {} 32 33 /// Constructor for cases when there are no relocations. 34 DWARFDataExtractor(StringRef Data, bool IsLittleEndian, uint8_t AddressSize) 35 : DataExtractor(Data, IsLittleEndian, AddressSize) {} 36 37 /// Extracts a value and applies a relocation to the result if 38 /// one exists for the given offset. 39 uint64_t getRelocatedValue(uint32_t Size, uint32_t *Off, 40 uint64_t *SectionIndex = nullptr) const; 41 42 /// Extracts an address-sized value and applies a relocation to the result if 43 /// one exists for the given offset. 44 uint64_t getRelocatedAddress(uint32_t *Off, uint64_t *SecIx = nullptr) const { 45 return getRelocatedValue(getAddressSize(), Off, SecIx); 46 } 47 48 /// Extracts a DWARF-encoded pointer in \p Offset using \p Encoding. 49 /// There is a DWARF encoding that uses a PC-relative adjustment. 50 /// For these values, \p AbsPosOffset is used to fix them, which should 51 /// reflect the absolute address of this pointer. 52 Optional<uint64_t> getEncodedPointer(uint32_t *Offset, uint8_t Encoding, 53 uint64_t AbsPosOffset = 0) const; 54 55 size_t size() const { return Section == nullptr ? 0 : Section->Data.size(); } 56 }; 57 58 } // end namespace llvm 59 60 #endif // LLVM_DEBUGINFO_DWARFDATAEXTRACTOR_H 61
