DWARFDebugRangeList.cpp revision 360784 
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
17using namespace llvm;
18
19void DWARFDebugRangeList::clear() {
20  Offset = -1ULL;
21  AddressSize = 0;
22  Entries.clear();
23}
24
25Error 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
60void 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
70DWARFAddressRangesVector 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}
96