예제 #1
0
Optional<DWARFDebugLoc::LocationList>
DWARFDebugLoc::parseOneLocationList(DWARFDataExtractor Data, unsigned *Offset) {
  LocationList LL;
  LL.Offset = *Offset;

  // 2.6.2 Location Lists
  // A location list entry consists of:
  while (true) {
    Entry E;
    if (!Data.isValidOffsetForDataOfSize(*Offset, 2 * Data.getAddressSize())) {
      llvm::errs() << "Location list overflows the debug_loc section.\n";
      return None;
    }

    // 1. A beginning address offset. ...
    E.Begin = Data.getRelocatedAddress(Offset);

    // 2. An ending address offset. ...
    E.End = Data.getRelocatedAddress(Offset);

    // The end of any given location list is marked by an end of list entry,
    // which consists of a 0 for the beginning address offset and a 0 for the
    // ending address offset.
    if (E.Begin == 0 && E.End == 0)
      return LL;

    if (!Data.isValidOffsetForDataOfSize(*Offset, 2)) {
      llvm::errs() << "Location list overflows the debug_loc section.\n";
      return None;
    }

    unsigned Bytes = Data.getU16(Offset);
    if (!Data.isValidOffsetForDataOfSize(*Offset, Bytes)) {
      llvm::errs() << "Location list overflows the debug_loc section.\n";
      return None;
    }
    // A single location description describing the location of the object...
    StringRef str = Data.getData().substr(*Offset, Bytes);
    *Offset += Bytes;
    E.Loc.reserve(str.size());
    std::copy(str.begin(), str.end(), std::back_inserter(E.Loc));
    LL.Entries.push_back(std::move(E));
  }
}
예제 #2
0
bool DWARFFormValue::extractValue(const DWARFDataExtractor &Data,
                                  uint32_t *OffsetPtr, DWARFFormParams FP,
                                  const DWARFUnit *CU) {
  U = CU;
  bool Indirect = false;
  bool IsBlock = false;
  Value.data = nullptr;
  // Read the value for the form into value and follow and DW_FORM_indirect
  // instances we run into
  do {
    Indirect = false;
    switch (Form) {
    case DW_FORM_addr:
    case DW_FORM_ref_addr: {
      uint16_t Size =
          (Form == DW_FORM_addr) ? FP.AddrSize : FP.getRefAddrByteSize();
      Value.uval = Data.getRelocatedValue(Size, OffsetPtr, &Value.SectionIndex);
      break;
    }
    case DW_FORM_exprloc:
    case DW_FORM_block:
      Value.uval = Data.getULEB128(OffsetPtr);
      IsBlock = true;
      break;
    case DW_FORM_block1:
      Value.uval = Data.getU8(OffsetPtr);
      IsBlock = true;
      break;
    case DW_FORM_block2:
      Value.uval = Data.getU16(OffsetPtr);
      IsBlock = true;
      break;
    case DW_FORM_block4:
      Value.uval = Data.getU32(OffsetPtr);
      IsBlock = true;
      break;
    case DW_FORM_data1:
    case DW_FORM_ref1:
    case DW_FORM_flag:
    case DW_FORM_strx1:
    case DW_FORM_addrx1:
      Value.uval = Data.getU8(OffsetPtr);
      break;
    case DW_FORM_data2:
    case DW_FORM_ref2:
    case DW_FORM_strx2:
    case DW_FORM_addrx2:
      Value.uval = Data.getU16(OffsetPtr);
      break;
    case DW_FORM_strx3:
      Value.uval = Data.getU24(OffsetPtr);
      break;
    case DW_FORM_data4:
    case DW_FORM_ref4:
    case DW_FORM_ref_sup4:
    case DW_FORM_strx4:
    case DW_FORM_addrx4:
      Value.uval = Data.getRelocatedValue(4, OffsetPtr);
      break;
    case DW_FORM_data8:
    case DW_FORM_ref8:
    case DW_FORM_ref_sup8:
      Value.uval = Data.getU64(OffsetPtr);
      break;
    case DW_FORM_data16:
      // Treat this like a 16-byte block.
      Value.uval = 16;
      IsBlock = true;
      break;
    case DW_FORM_sdata:
      Value.sval = Data.getSLEB128(OffsetPtr);
      break;
    case DW_FORM_udata:
    case DW_FORM_ref_udata:
      Value.uval = Data.getULEB128(OffsetPtr);
      break;
    case DW_FORM_string:
      Value.cstr = Data.getCStr(OffsetPtr);
      break;
    case DW_FORM_indirect:
      Form = static_cast<dwarf::Form>(Data.getULEB128(OffsetPtr));
      Indirect = true;
      break;
    case DW_FORM_strp:
    case DW_FORM_sec_offset:
    case DW_FORM_GNU_ref_alt:
    case DW_FORM_GNU_strp_alt:
    case DW_FORM_line_strp:
    case DW_FORM_strp_sup: {
      Value.uval =
          Data.getRelocatedValue(FP.getDwarfOffsetByteSize(), OffsetPtr);
      break;
    }
    case DW_FORM_flag_present:
      Value.uval = 1;
      break;
    case DW_FORM_ref_sig8:
      Value.uval = Data.getU64(OffsetPtr);
      break;
    case DW_FORM_GNU_addr_index:
    case DW_FORM_GNU_str_index:
    case DW_FORM_strx:
      Value.uval = Data.getULEB128(OffsetPtr);
      break;
    default:
      // DWARFFormValue::skipValue() will have caught this and caused all
      // DWARF DIEs to fail to be parsed, so this code is not be reachable.
      llvm_unreachable("unsupported form");
    }
  } while (Indirect);

  if (IsBlock) {
    StringRef Str = Data.getData().substr(*OffsetPtr, Value.uval);
    Value.data = nullptr;
    if (!Str.empty()) {
      Value.data = reinterpret_cast<const uint8_t *>(Str.data());
      *OffsetPtr += Value.uval;
    }
  }

  return true;
}