lib/ObjectYAML/DWARFVisitor.cpp

   1 //===--- DWARFVisitor.cpp ---------------------------------------*- 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 //===----------------------------------------------------------------------===//
  10
  11 #include "DWARFVisitor.h"
  12 #include "llvm/ObjectYAML/DWARFYAML.h"
  13
  14 using namespace llvm;
  15
  16 template <typename T>
  17 void DWARFYAML::VisitorImpl<T>::onVariableSizeValue(uint64_t U, unsigned Size) {
  18   switch (Size) {
  19   case 8:
  20     onValue((uint64_t)U);
  21     break;
  22   case 4:
  23     onValue((uint32_t)U);
  24     break;
  25   case 2:
  26     onValue((uint16_t)U);
  27     break;
  28   case 1:
  29     onValue((uint8_t)U);
  30     break;
  31   default:
  32     llvm_unreachable("Invalid integer write size.");
  33   }
  34 }
  35
  36 static unsigned getOffsetSize(const DWARFYAML::Unit &Unit) {
  37   return Unit.Length.isDWARF64() ? 8 : 4;
  38 }
  39
  40 static unsigned getRefSize(const DWARFYAML::Unit &Unit) {
  41   if (Unit.Version == 2)
  42     return Unit.AddrSize;
  43   return getOffsetSize(Unit);
  44 }
  45
  46 template <typename T> void DWARFYAML::VisitorImpl<T>::traverseDebugInfo() {
  47   for (auto &Unit : DebugInfo.CompileUnits) {
  48     onStartCompileUnit(Unit);
  49     auto FirstAbbrevCode = Unit.Entries[0].AbbrCode;
  50
  51     for (auto &Entry : Unit.Entries) {
  52       onStartDIE(Unit, Entry);
  53       if (Entry.AbbrCode == 0u)
  54         continue;
  55       auto &Abbrev = DebugInfo.AbbrevDecls[Entry.AbbrCode - FirstAbbrevCode];
  56       auto FormVal = Entry.Values.begin();
  57       auto AbbrForm = Abbrev.Attributes.begin();
  58       for (;
  59            FormVal != Entry.Values.end() && AbbrForm != Abbrev.Attributes.end();
  60            ++FormVal, ++AbbrForm) {
  61         onForm(*AbbrForm, *FormVal);
  62         dwarf::Form Form = AbbrForm->Form;
  63         bool Indirect;
  64         do {
  65           Indirect = false;
  66           switch (Form) {
  67           case dwarf::DW_FORM_addr:
  68             onVariableSizeValue(FormVal->Value, Unit.AddrSize);
  69             break;
  70           case dwarf::DW_FORM_ref_addr:
  71             onVariableSizeValue(FormVal->Value, getRefSize(Unit));
  72             break;
  73           case dwarf::DW_FORM_exprloc:
  74           case dwarf::DW_FORM_block:
  75             onValue((uint64_t)FormVal->BlockData.size(), true);
  76             onValue(
  77                 MemoryBufferRef(StringRef((const char *)&FormVal->BlockData[0],
  78                                           FormVal->BlockData.size()),
  79                                 ""));
  80             break;
  81           case dwarf::DW_FORM_block1: {
  82             auto writeSize = FormVal->BlockData.size();
  83             onValue((uint8_t)writeSize);
  84             onValue(
  85                 MemoryBufferRef(StringRef((const char *)&FormVal->BlockData[0],
  86                                           FormVal->BlockData.size()),
  87                                 ""));
  88             break;
  89           }
  90           case dwarf::DW_FORM_block2: {
  91             auto writeSize = FormVal->BlockData.size();
  92             onValue((uint16_t)writeSize);
  93             onValue(
  94                 MemoryBufferRef(StringRef((const char *)&FormVal->BlockData[0],
  95                                           FormVal->BlockData.size()),
  96                                 ""));
  97             break;
  98           }
  99           case dwarf::DW_FORM_block4: {
 100             auto writeSize = FormVal->BlockData.size();
 101             onValue((uint32_t)writeSize);
 102             onValue(
 103                 MemoryBufferRef(StringRef((const char *)&FormVal->BlockData[0],
 104                                           FormVal->BlockData.size()),
 105                                 ""));
 106             break;
 107           }
 108           case dwarf::DW_FORM_data1:
 109           case dwarf::DW_FORM_ref1:
 110           case dwarf::DW_FORM_flag:
 111           case dwarf::DW_FORM_strx1:
 112           case dwarf::DW_FORM_addrx1:
 113             onValue((uint8_t)FormVal->Value);
 114             break;
 115           case dwarf::DW_FORM_data2:
 116           case dwarf::DW_FORM_ref2:
 117           case dwarf::DW_FORM_strx2:
 118           case dwarf::DW_FORM_addrx2:
 119             onValue((uint16_t)FormVal->Value);
 120             break;
 121           case dwarf::DW_FORM_data4:
 122           case dwarf::DW_FORM_ref4:
 123           case dwarf::DW_FORM_ref_sup4:
 124           case dwarf::DW_FORM_strx4:
 125           case dwarf::DW_FORM_addrx4:
 126             onValue((uint32_t)FormVal->Value);
 127             break;
 128           case dwarf::DW_FORM_data8:
 129           case dwarf::DW_FORM_ref8:
 130           case dwarf::DW_FORM_ref_sup8:
 131             onValue((uint64_t)FormVal->Value);
 132             break;
 133           case dwarf::DW_FORM_sdata:
 134             onValue((int64_t)FormVal->Value, true);
 135             break;
 136           case dwarf::DW_FORM_udata:
 137           case dwarf::DW_FORM_ref_udata:
 138             onValue((uint64_t)FormVal->Value, true);
 139             break;
 140           case dwarf::DW_FORM_string:
 141             onValue(FormVal->CStr);
 142             break;
 143           case dwarf::DW_FORM_indirect:
 144             onValue((uint64_t)FormVal->Value, true);
 145             Indirect = true;
 146             Form = static_cast<dwarf::Form>((uint64_t)FormVal->Value);
 147             ++FormVal;
 148             break;
 149           case dwarf::DW_FORM_strp:
 150           case dwarf::DW_FORM_sec_offset:
 151           case dwarf::DW_FORM_GNU_ref_alt:
 152           case dwarf::DW_FORM_GNU_strp_alt:
 153           case dwarf::DW_FORM_line_strp:
 154           case dwarf::DW_FORM_strp_sup:
 155             onVariableSizeValue(FormVal->Value, getOffsetSize(Unit));
 156             break;
 157           case dwarf::DW_FORM_ref_sig8:
 158             onValue((uint64_t)FormVal->Value);
 159             break;
 160           case dwarf::DW_FORM_GNU_addr_index:
 161           case dwarf::DW_FORM_GNU_str_index:
 162             onValue((uint64_t)FormVal->Value, true);
 163             break;
 164           default:
 165             break;
 166           }
 167         } while (Indirect);
 168       }
 169       onEndDIE(Unit, Entry);
 170     }
 171     onEndCompileUnit(Unit);
 172   }
 173 }
 174
 175 // Explicitly instantiate the two template expansions.
 176 template class DWARFYAML::VisitorImpl<DWARFYAML::Data>;
 177 template class DWARFYAML::VisitorImpl<const DWARFYAML::Data>;