1 //===- DWARFDebugLoc.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_DWARF_DWARFDEBUGLOC_H 10 #define LLVM_DEBUGINFO_DWARF_DWARFDEBUGLOC_H 11 12 #include "llvm/ADT/SmallVector.h" 13 #include "llvm/DebugInfo/DWARF/DWARFDataExtractor.h" 14 #include "llvm/Support/Compiler.h" 15 #include "llvm/Support/Errc.h" 16 #include <cstdint> 17 18 namespace llvm { 19 class DWARFUnit; 20 class MCRegisterInfo; 21 class raw_ostream; 22 class DWARFObject; 23 struct DIDumpOptions; 24 struct DWARFLocationExpression; 25 namespace object { 26 struct SectionedAddress; 27 } 28 29 /// A single location within a location list. Entries are stored in the DWARF5 30 /// form even if they originally come from a DWARF<=4 location list. 31 struct DWARFLocationEntry { 32 /// The entry kind (DW_LLE_***). 33 uint8_t Kind; 34 35 /// The first value of the location entry (if applicable). 36 uint64_t Value0; 37 38 /// The second value of the location entry (if applicable). 39 uint64_t Value1; 40 41 /// The index of the section this entry is relative to (if applicable). 42 uint64_t SectionIndex; 43 44 /// The location expression itself (if applicable). 45 SmallVector<uint8_t, 4> Loc; 46 }; 47 48 /// An abstract base class for various kinds of location tables (.debug_loc, 49 /// .debug_loclists, and their dwo variants). 50 class DWARFLocationTable { 51 public: DWARFLocationTable(DWARFDataExtractor Data)52 DWARFLocationTable(DWARFDataExtractor Data) : Data(std::move(Data)) {} 53 virtual ~DWARFLocationTable() = default; 54 55 /// Call the user-provided callback for each entry (including the end-of-list 56 /// entry) in the location list starting at \p Offset. The callback can return 57 /// false to terminate the iteration early. Returns an error if it was unable 58 /// to parse the entire location list correctly. Upon successful termination 59 /// \p Offset will be updated point past the end of the list. 60 virtual Error visitLocationList( 61 uint64_t *Offset, 62 function_ref<bool(const DWARFLocationEntry &)> Callback) const = 0; 63 64 /// Dump the location list at the given \p Offset. The function returns true 65 /// iff it has successfully reched the end of the list. This means that one 66 /// can attempt to parse another list after the current one (\p Offset will be 67 /// updated to point past the end of the current list). 68 LLVM_ABI bool 69 dumpLocationList(uint64_t *Offset, raw_ostream &OS, 70 std::optional<object::SectionedAddress> BaseAddr, 71 const DWARFObject &Obj, DWARFUnit *U, DIDumpOptions DumpOpts, 72 unsigned Indent) const; 73 74 LLVM_ABI Error visitAbsoluteLocationList( 75 uint64_t Offset, std::optional<object::SectionedAddress> BaseAddr, 76 std::function<std::optional<object::SectionedAddress>(uint32_t)> 77 LookupAddr, 78 function_ref<bool(Expected<DWARFLocationExpression>)> Callback) const; 79 getData()80 const DWARFDataExtractor &getData() { return Data; } 81 82 protected: 83 DWARFDataExtractor Data; 84 85 virtual void dumpRawEntry(const DWARFLocationEntry &Entry, raw_ostream &OS, 86 unsigned Indent, DIDumpOptions DumpOpts, 87 const DWARFObject &Obj) const = 0; 88 }; 89 90 class LLVM_ABI DWARFDebugLoc final : public DWARFLocationTable { 91 public: 92 /// A list of locations that contain one variable. 93 struct LocationList { 94 /// The beginning offset where this location list is stored in the debug_loc 95 /// section. 96 uint64_t Offset; 97 /// All the locations in which the variable is stored. 98 SmallVector<DWARFLocationEntry, 2> Entries; 99 }; 100 101 private: 102 using LocationLists = SmallVector<LocationList, 4>; 103 104 /// A list of all the variables in the debug_loc section, each one describing 105 /// the locations in which the variable is stored. 106 LocationLists Locations; 107 108 public: DWARFDebugLoc(DWARFDataExtractor Data)109 DWARFDebugLoc(DWARFDataExtractor Data) 110 : DWARFLocationTable(std::move(Data)) {} 111 112 /// Print the location lists found within the debug_loc section. 113 void dump(raw_ostream &OS, const DWARFObject &Obj, DIDumpOptions DumpOpts, 114 std::optional<uint64_t> Offset) const; 115 116 Error visitLocationList( 117 uint64_t *Offset, 118 function_ref<bool(const DWARFLocationEntry &)> Callback) const override; 119 120 protected: 121 void dumpRawEntry(const DWARFLocationEntry &Entry, raw_ostream &OS, 122 unsigned Indent, DIDumpOptions DumpOpts, 123 const DWARFObject &Obj) const override; 124 }; 125 126 class LLVM_ABI DWARFDebugLoclists final : public DWARFLocationTable { 127 public: DWARFDebugLoclists(DWARFDataExtractor Data,uint16_t Version)128 DWARFDebugLoclists(DWARFDataExtractor Data, uint16_t Version) 129 : DWARFLocationTable(std::move(Data)), Version(Version) {} 130 131 Error visitLocationList( 132 uint64_t *Offset, 133 function_ref<bool(const DWARFLocationEntry &)> Callback) const override; 134 135 /// Dump all location lists within the given range. 136 void dumpRange(uint64_t StartOffset, uint64_t Size, raw_ostream &OS, 137 const DWARFObject &Obj, DIDumpOptions DumpOpts); 138 139 protected: 140 void dumpRawEntry(const DWARFLocationEntry &Entry, raw_ostream &OS, 141 unsigned Indent, DIDumpOptions DumpOpts, 142 const DWARFObject &Obj) const override; 143 144 private: 145 uint16_t Version; 146 }; 147 148 class LLVM_ABI ResolverError : public ErrorInfo<ResolverError> { 149 public: 150 static char ID; 151 ResolverError(uint32_t Index,dwarf::LoclistEntries Kind)152 ResolverError(uint32_t Index, dwarf::LoclistEntries Kind) : Index(Index), Kind(Kind) {} 153 154 void log(raw_ostream &OS) const override; convertToErrorCode()155 std::error_code convertToErrorCode() const override { 156 return llvm::errc::invalid_argument; 157 } 158 159 private: 160 uint32_t Index; 161 dwarf::LoclistEntries Kind; 162 }; 163 164 } // end namespace llvm 165 166 #endif // LLVM_DEBUGINFO_DWARF_DWARFDEBUGLOC_H 167