lib/DebugInfo/DWARF/DWARFDebugRangeList.cpp

   1 //===- DWARFDebugRangesList.cpp -------------------------------------------===//
   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 #include "llvm/DebugInfo/DWARF/DWARFDebugRangeList.h"
  10 #include "llvm/DebugInfo/DWARF/DWARFContext.h"
  11 #include "llvm/Support/Errc.h"
  12 #include "llvm/Support/Format.h"
  13 #include "llvm/Support/raw_ostream.h"
  14 #include <cinttypes>
  15 #include <cstdint>
  16
  17 using namespace llvm;
  18
  19 void DWARFDebugRangeList::clear() {
  20   Offset = -1ULL;
  21   AddressSize = 0;
  22   Entries.clear();
  23 }
  24
  25 Error DWARFDebugRangeList::extract(const DWARFDataExtractor &data,
  26                                    uint64_t *offset_ptr) {
  27   clear();
  28   if (!data.isValidOffset(*offset_ptr))
  29     return createStringError(errc::invalid_argument,
  30                        "invalid range list offset 0x%" PRIx64, *offset_ptr);
  31
  32   AddressSize = data.getAddressSize();
  33   if (AddressSize != 4 && AddressSize != 8)
  34     return createStringError(errc::invalid_argument,
  35                        "invalid address size: %" PRIu8, AddressSize);
  36   Offset = *offset_ptr;
  37   while (true) {
  38     RangeListEntry Entry;
  39     Entry.SectionIndex = -1ULL;
  40
  41     uint64_t prev_offset = *offset_ptr;
  42     Entry.StartAddress = data.getRelocatedAddress(offset_ptr);
  43     Entry.EndAddress =
  44         data.getRelocatedAddress(offset_ptr, &Entry.SectionIndex);
  45
  46     // Check that both values were extracted correctly.
  47     if (*offset_ptr != prev_offset + 2 * AddressSize) {
  48       clear();
  49       return createStringError(errc::invalid_argument,
  50                          "invalid range list entry at offset 0x%" PRIx64,
  51                          prev_offset);
  52     }
  53     if (Entry.isEndOfListEntry())
  54       break;
  55     Entries.push_back(Entry);
  56   }
  57   return Error::success();
  58 }
  59
  60 void DWARFDebugRangeList::dump(raw_ostream &OS) const {
  61   for (const RangeListEntry &RLE : Entries) {
  62     const char *format_str =
  63         (AddressSize == 4 ? "%08" PRIx64 " %08" PRIx64 " %08" PRIx64 "\n"
  64                           : "%08" PRIx64 " %016" PRIx64 " %016" PRIx64 "\n");
  65     OS << format(format_str, Offset, RLE.StartAddress, RLE.EndAddress);
  66   }
  67   OS << format("%08" PRIx64 " <End of list>\n", Offset);
  68 }
  69
  70 DWARFAddressRangesVector DWARFDebugRangeList::getAbsoluteRanges(
  71     llvm::Optional<object::SectionedAddress> BaseAddr) const {
  72   DWARFAddressRangesVector Res;
  73   for (const RangeListEntry &RLE : Entries) {
  74     if (RLE.isBaseAddressSelectionEntry(AddressSize)) {
  75       BaseAddr = {RLE.EndAddress, RLE.SectionIndex};
  76       continue;
  77     }
  78
  79     DWARFAddressRange E;
  80     E.LowPC = RLE.StartAddress;
  81     E.HighPC = RLE.EndAddress;
  82     E.SectionIndex = RLE.SectionIndex;
  83     // Base address of a range list entry is determined by the closest preceding
  84     // base address selection entry in the same range list. It defaults to the
  85     // base address of the compilation unit if there is no such entry.
  86     if (BaseAddr) {
  87       E.LowPC += BaseAddr->Address;
  88       E.HighPC += BaseAddr->Address;
  89       if (E.SectionIndex == -1ULL)
  90         E.SectionIndex = BaseAddr->SectionIndex;
  91     }
  92     Res.push_back(E);
  93   }
  94   return Res;
  95 }