1 //===- DWARFDebugArangeSet.cpp --------------------------------------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 #include "llvm/DebugInfo/DWARF/DWARFDebugArangeSet.h"
11 #include "llvm/Support/Format.h"
12 #include "llvm/Support/raw_ostream.h"
20 void DWARFDebugArangeSet::clear() {
22 std::memset(&HeaderData, 0, sizeof(Header));
23 ArangeDescriptors.clear();
27 DWARFDebugArangeSet::extract(DataExtractor data, uint32_t *offset_ptr) {
28 if (data.isValidOffset(*offset_ptr)) {
29 ArangeDescriptors.clear();
32 // 7.20 Address Range Table
34 // Each set of entries in the table of address ranges contained in
35 // the .debug_aranges section begins with a header consisting of: a
36 // 4-byte length containing the length of the set of entries for this
37 // compilation unit, not including the length field itself; a 2-byte
38 // version identifier containing the value 2 for DWARF Version 2; a
39 // 4-byte offset into the.debug_infosection; a 1-byte unsigned integer
40 // containing the size in bytes of an address (or the offset portion of
41 // an address for segmented addressing) on the target system; and a
42 // 1-byte unsigned integer containing the size in bytes of a segment
43 // descriptor on the target system. This header is followed by a series
44 // of tuples. Each tuple consists of an address and a length, each in
45 // the size appropriate for an address on the target architecture.
46 HeaderData.Length = data.getU32(offset_ptr);
47 HeaderData.Version = data.getU16(offset_ptr);
48 HeaderData.CuOffset = data.getU32(offset_ptr);
49 HeaderData.AddrSize = data.getU8(offset_ptr);
50 HeaderData.SegSize = data.getU8(offset_ptr);
52 // Perform basic validation of the header fields.
53 if (!data.isValidOffsetForDataOfSize(Offset, HeaderData.Length) ||
54 (HeaderData.AddrSize != 4 && HeaderData.AddrSize != 8)) {
59 // The first tuple following the header in each set begins at an offset
60 // that is a multiple of the size of a single tuple (that is, twice the
61 // size of an address). The header is padded, if necessary, to the
62 // appropriate boundary.
63 const uint32_t header_size = *offset_ptr - Offset;
64 const uint32_t tuple_size = HeaderData.AddrSize * 2;
65 uint32_t first_tuple_offset = 0;
66 while (first_tuple_offset < header_size)
67 first_tuple_offset += tuple_size;
69 *offset_ptr = Offset + first_tuple_offset;
71 Descriptor arangeDescriptor;
73 static_assert(sizeof(arangeDescriptor.Address) ==
74 sizeof(arangeDescriptor.Length),
75 "Different datatypes for addresses and sizes!");
76 assert(sizeof(arangeDescriptor.Address) >= HeaderData.AddrSize);
78 while (data.isValidOffset(*offset_ptr)) {
79 arangeDescriptor.Address = data.getUnsigned(offset_ptr, HeaderData.AddrSize);
80 arangeDescriptor.Length = data.getUnsigned(offset_ptr, HeaderData.AddrSize);
82 // Each set of tuples is terminated by a 0 for the address and 0
84 if (arangeDescriptor.Address || arangeDescriptor.Length)
85 ArangeDescriptors.push_back(arangeDescriptor);
87 break; // We are done if we get a zero address and length
90 return !ArangeDescriptors.empty();
95 void DWARFDebugArangeSet::dump(raw_ostream &OS) const {
96 OS << format("Address Range Header: length = 0x%8.8x, version = 0x%4.4x, ",
97 HeaderData.Length, HeaderData.Version)
98 << format("cu_offset = 0x%8.8x, addr_size = 0x%2.2x, seg_size = 0x%2.2x\n",
99 HeaderData.CuOffset, HeaderData.AddrSize, HeaderData.SegSize);
101 const uint32_t hex_width = HeaderData.AddrSize * 2;
102 for (const auto &Desc : ArangeDescriptors) {
103 OS << format("[0x%*.*" PRIx64 " -", hex_width, hex_width, Desc.Address)
104 << format(" 0x%*.*" PRIx64 ")\n",
105 hex_width, hex_width, Desc.getEndAddress());