1 //===- DWARFDebugRangesList.cpp -------------------------------------------===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 
10 #include "llvm/DebugInfo/DWARF/DWARFDebugRangeList.h"
11 #include "llvm/DebugInfo/DWARF/DWARFContext.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 = -1U;
21   AddressSize = 0;
22   Entries.clear();
23 }
24 
25 bool DWARFDebugRangeList::extract(const DWARFDataExtractor &data,
26                                   uint32_t *offset_ptr) {
27   clear();
28   if (!data.isValidOffset(*offset_ptr))
29     return false;
30   AddressSize = data.getAddressSize();
31   if (AddressSize != 4 && AddressSize != 8)
32     return false;
33   Offset = *offset_ptr;
34   while (true) {
35     RangeListEntry Entry;
36     Entry.SectionIndex = -1ULL;
37 
38     uint32_t prev_offset = *offset_ptr;
39     Entry.StartAddress = data.getRelocatedAddress(offset_ptr);
40     Entry.EndAddress =
41         data.getRelocatedAddress(offset_ptr, &Entry.SectionIndex);
42 
43     // Check that both values were extracted correctly.
44     if (*offset_ptr != prev_offset + 2 * AddressSize) {
45       clear();
46       return false;
47     }
48     if (Entry.isEndOfListEntry())
49       break;
50     Entries.push_back(Entry);
51   }
52   return true;
53 }
54 
55 void DWARFDebugRangeList::dump(raw_ostream &OS) const {
56   for (const RangeListEntry &RLE : Entries) {
57     const char *format_str = (AddressSize == 4
58                               ? "%08x %08"  PRIx64 " %08"  PRIx64 "\n"
59                               : "%08x %016" PRIx64 " %016" PRIx64 "\n");
60     OS << format(format_str, Offset, RLE.StartAddress, RLE.EndAddress);
61   }
62   OS << format("%08x <End of list>\n", Offset);
63 }
64 
65 DWARFAddressRangesVector DWARFDebugRangeList::getAbsoluteRanges(
66     llvm::Optional<BaseAddress> BaseAddr) const {
67   DWARFAddressRangesVector Res;
68   for (const RangeListEntry &RLE : Entries) {
69     if (RLE.isBaseAddressSelectionEntry(AddressSize)) {
70       BaseAddr = {RLE.EndAddress, RLE.SectionIndex};
71       continue;
72     }
73 
74     DWARFAddressRange E;
75     E.LowPC = RLE.StartAddress;
76     E.HighPC = RLE.EndAddress;
77     E.SectionIndex = RLE.SectionIndex;
78     // Base address of a range list entry is determined by the closest preceding
79     // base address selection entry in the same range list. It defaults to the
80     // base address of the compilation unit if there is no such entry.
81     if (BaseAddr) {
82       E.LowPC += BaseAddr->Address;
83       E.HighPC += BaseAddr->Address;
84       if (E.SectionIndex == -1ULL)
85         E.SectionIndex = BaseAddr->SectionIndex;
86     }
87     Res.push_back(E);
88   }
89   return Res;
90 }
91