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 #include <utility>
17 
18 using namespace llvm;
19 
20 raw_ostream &llvm::operator<<(raw_ostream &OS, const DWARFAddressRange &R) {
21   return OS << format("[0x%16.16" PRIx64 ", 0x%16.16" PRIx64 ")", R.LowPC,
22                       R.HighPC);
23 }
24 
25 void DWARFDebugRangeList::clear() {
26   Offset = -1U;
27   AddressSize = 0;
28   Entries.clear();
29 }
30 
31 bool DWARFDebugRangeList::extract(const DWARFDataExtractor &data,
32                                   uint32_t *offset_ptr) {
33   clear();
34   if (!data.isValidOffset(*offset_ptr))
35     return false;
36   AddressSize = data.getAddressSize();
37   if (AddressSize != 4 && AddressSize != 8)
38     return false;
39   Offset = *offset_ptr;
40   while (true) {
41     RangeListEntry Entry;
42     Entry.SectionIndex = -1ULL;
43 
44     uint32_t prev_offset = *offset_ptr;
45     Entry.StartAddress = data.getRelocatedAddress(offset_ptr);
46     Entry.EndAddress =
47         data.getRelocatedAddress(offset_ptr, &Entry.SectionIndex);
48 
49     // Check that both values were extracted correctly.
50     if (*offset_ptr != prev_offset + 2 * AddressSize) {
51       clear();
52       return false;
53     }
54     if (Entry.isEndOfListEntry())
55       break;
56     Entries.push_back(Entry);
57   }
58   return true;
59 }
60 
61 void DWARFDebugRangeList::dump(raw_ostream &OS) const {
62   for (const RangeListEntry &RLE : Entries) {
63     const char *format_str = (AddressSize == 4
64                               ? "%08x %08"  PRIx64 " %08"  PRIx64 "\n"
65                               : "%08x %016" PRIx64 " %016" PRIx64 "\n");
66     OS << format(format_str, Offset, RLE.StartAddress, RLE.EndAddress);
67   }
68   OS << format("%08x <End of list>\n", Offset);
69 }
70 
71 DWARFAddressRangesVector DWARFDebugRangeList::getAbsoluteRanges(
72     llvm::Optional<BaseAddress> BaseAddr) const {
73   DWARFAddressRangesVector Res;
74   for (const RangeListEntry &RLE : Entries) {
75     if (RLE.isBaseAddressSelectionEntry(AddressSize)) {
76       BaseAddr = {RLE.EndAddress, RLE.SectionIndex};
77       continue;
78     }
79 
80     DWARFAddressRange E;
81     E.LowPC = RLE.StartAddress;
82     E.HighPC = RLE.EndAddress;
83     E.SectionIndex = RLE.SectionIndex;
84     // Base address of a range list entry is determined by the closest preceding
85     // base address selection entry in the same range list. It defaults to the
86     // base address of the compilation unit if there is no such entry.
87     if (BaseAddr) {
88       E.LowPC += BaseAddr->Address;
89       E.HighPC += BaseAddr->Address;
90       if (E.SectionIndex == -1ULL)
91         E.SectionIndex = BaseAddr->SectionIndex;
92     }
93     Res.push_back(E);
94   }
95   return Res;
96 }
97