1 //===-- DWARFDebugAranges.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 "DWARFDebugAranges.h"
10 #include "DWARFDebugArangeSet.h"
11 #include "DWARFUnit.h"
12 #include "LogChannelDWARF.h"
13 #include "lldb/Utility/Log.h"
14 #include "lldb/Utility/Timer.h"
15 
16 using namespace lldb;
17 using namespace lldb_private;
18 
19 // Constructor
20 DWARFDebugAranges::DWARFDebugAranges() : m_aranges() {}
21 
22 // CountArangeDescriptors
23 class CountArangeDescriptors {
24 public:
25   CountArangeDescriptors(uint32_t &count_ref) : count(count_ref) {
26     //      printf("constructor CountArangeDescriptors()\n");
27   }
28   void operator()(const DWARFDebugArangeSet &set) {
29     count += set.NumDescriptors();
30   }
31   uint32_t &count;
32 };
33 
34 // Extract
35 void DWARFDebugAranges::extract(const DWARFDataExtractor &debug_aranges_data) {
36   lldb::offset_t offset = 0;
37 
38   DWARFDebugArangeSet set;
39   Range range;
40   while (debug_aranges_data.ValidOffset(offset)) {
41     const lldb::offset_t set_offset = offset;
42     if (llvm::Error error = set.extract(debug_aranges_data, &offset)) {
43       Log *log = LogChannelDWARF::GetLogIfAll(DWARF_LOG_DEBUG_INFO);
44       LLDB_LOG_ERROR(log, std::move(error),
45                      "DWARFDebugAranges::extract failed to extract "
46                      ".debug_aranges set at offset %#" PRIx64,
47                      set_offset);
48     } else {
49       const uint32_t num_descriptors = set.NumDescriptors();
50       if (num_descriptors > 0) {
51         const dw_offset_t cu_offset = set.GetHeader().cu_offset;
52 
53         for (uint32_t i = 0; i < num_descriptors; ++i) {
54           const DWARFDebugArangeSet::Descriptor &descriptor =
55               set.GetDescriptorRef(i);
56           m_aranges.Append(RangeToDIE::Entry(descriptor.address,
57                                              descriptor.length, cu_offset));
58         }
59       }
60     }
61     // Always use the previous DWARFDebugArangeSet's information to calculate
62     // the offset of the next DWARFDebugArangeSet in case we entouncter an
63     // error in the current DWARFDebugArangeSet and our offset position is
64     // still in the middle of the data. If we do this, we can parse all valid
65     // DWARFDebugArangeSet objects without returning invalid errors.
66     offset = set.GetNextOffset();
67     set.Clear();
68   }
69 }
70 
71 void DWARFDebugAranges::Dump(Log *log) const {
72   if (log == nullptr)
73     return;
74 
75   const size_t num_entries = m_aranges.GetSize();
76   for (size_t i = 0; i < num_entries; ++i) {
77     const RangeToDIE::Entry *entry = m_aranges.GetEntryAtIndex(i);
78     if (entry)
79       LLDB_LOGF(log, "0x%8.8x: [0x%" PRIx64 " - 0x%" PRIx64 ")", entry->data,
80                 entry->GetRangeBase(), entry->GetRangeEnd());
81   }
82 }
83 
84 void DWARFDebugAranges::AppendRange(dw_offset_t offset, dw_addr_t low_pc,
85                                     dw_addr_t high_pc) {
86   if (high_pc > low_pc)
87     m_aranges.Append(RangeToDIE::Entry(low_pc, high_pc - low_pc, offset));
88 }
89 
90 void DWARFDebugAranges::Sort(bool minimize) {
91   LLDB_SCOPED_TIMERF("%s this = %p", LLVM_PRETTY_FUNCTION,
92                      static_cast<void *>(this));
93 
94   m_aranges.Sort();
95   m_aranges.CombineConsecutiveEntriesWithEqualData();
96 }
97 
98 // FindAddress
99 dw_offset_t DWARFDebugAranges::FindAddress(dw_addr_t address) const {
100   const RangeToDIE::Entry *entry = m_aranges.FindEntryThatContains(address);
101   if (entry)
102     return entry->data;
103   return DW_INVALID_OFFSET;
104 }
105