1 //===- DWARFDataExtractor.h -------------------------------------*- C++ -*-===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 9 #ifndef LLVM_DEBUGINFO_DWARFDATAEXTRACTOR_H 10 #define LLVM_DEBUGINFO_DWARFDATAEXTRACTOR_H 11 12 #include "llvm/DebugInfo/DWARF/DWARFSection.h" 13 #include "llvm/Support/DataExtractor.h" 14 15 namespace llvm { 16 class DWARFObject; 17 18 /// A DataExtractor (typically for an in-memory copy of an object-file section) 19 /// plus a relocation map for that section, if there is one. 20 class DWARFDataExtractor : public DataExtractor { 21 const DWARFObject *Obj = nullptr; 22 const DWARFSection *Section = nullptr; 23 24 public: 25 /// Constructor for the normal case of extracting data from a DWARF section. 26 /// The DWARFSection's lifetime must be at least as long as the extractor's. DWARFDataExtractor(const DWARFObject & Obj,const DWARFSection & Section,bool IsLittleEndian,uint8_t AddressSize)27 DWARFDataExtractor(const DWARFObject &Obj, const DWARFSection &Section, 28 bool IsLittleEndian, uint8_t AddressSize) 29 : DataExtractor(Section.Data, IsLittleEndian, AddressSize), Obj(&Obj), 30 Section(&Section) {} 31 32 /// Constructor for cases when there are no relocations. DWARFDataExtractor(StringRef Data,bool IsLittleEndian,uint8_t AddressSize)33 DWARFDataExtractor(StringRef Data, bool IsLittleEndian, uint8_t AddressSize) 34 : DataExtractor(Data, IsLittleEndian, AddressSize) {} 35 36 /// Extracts a value and applies a relocation to the result if 37 /// one exists for the given offset. 38 uint64_t getRelocatedValue(uint32_t Size, uint64_t *Off, 39 uint64_t *SectionIndex = nullptr, 40 Error *Err = 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(uint64_t *Off, uint64_t *SecIx = nullptr) const { 45 return getRelocatedValue(getAddressSize(), Off, SecIx); 46 } 47 uint64_t getRelocatedAddress(Cursor &C, uint64_t *SecIx = nullptr) const { 48 return getRelocatedValue(getAddressSize(), &getOffset(C), SecIx, 49 &getError(C)); 50 } 51 52 /// Extracts a DWARF-encoded pointer in \p Offset using \p Encoding. 53 /// There is a DWARF encoding that uses a PC-relative adjustment. 54 /// For these values, \p AbsPosOffset is used to fix them, which should 55 /// reflect the absolute address of this pointer. 56 Optional<uint64_t> getEncodedPointer(uint64_t *Offset, uint8_t Encoding, 57 uint64_t AbsPosOffset = 0) const; 58 }; 59 60 } // end namespace llvm 61 62 #endif // LLVM_DEBUGINFO_DWARFDATAEXTRACTOR_H 63