llvm-6502/lib/DebugInfo/DWARFDebugArangeSet.cpp
Frederic Riss 7e5492d27d [DebugInfo] Move all DWARF headers to the public include directory.
dsymutil needs access to DWARF specific inforamtion, the small DIContext
wrapper isn't sufficient. Other DWARF consumers might want to use it too
(I'm looking at you lldb).

Differential Revision: http://reviews.llvm.org/D6694

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@224594 91177308-0d34-0410-b5e6-96231b3b80d8
2014-12-19 18:26:33 +00:00

105 lines
4.2 KiB
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//===-- DWARFDebugArangeSet.cpp -------------------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "llvm/DebugInfo/DWARFDebugArangeSet.h"
#include "llvm/Support/Format.h"
#include "llvm/Support/raw_ostream.h"
#include <algorithm>
#include <cassert>
using namespace llvm;
void DWARFDebugArangeSet::clear() {
Offset = -1U;
std::memset(&HeaderData, 0, sizeof(Header));
ArangeDescriptors.clear();
}
bool
DWARFDebugArangeSet::extract(DataExtractor data, uint32_t *offset_ptr) {
if (data.isValidOffset(*offset_ptr)) {
ArangeDescriptors.clear();
Offset = *offset_ptr;
// 7.20 Address Range Table
//
// Each set of entries in the table of address ranges contained in
// the .debug_aranges section begins with a header consisting of: a
// 4-byte length containing the length of the set of entries for this
// compilation unit, not including the length field itself; a 2-byte
// version identifier containing the value 2 for DWARF Version 2; a
// 4-byte offset into the.debug_infosection; a 1-byte unsigned integer
// containing the size in bytes of an address (or the offset portion of
// an address for segmented addressing) on the target system; and a
// 1-byte unsigned integer containing the size in bytes of a segment
// descriptor on the target system. This header is followed by a series
// of tuples. Each tuple consists of an address and a length, each in
// the size appropriate for an address on the target architecture.
HeaderData.Length = data.getU32(offset_ptr);
HeaderData.Version = data.getU16(offset_ptr);
HeaderData.CuOffset = data.getU32(offset_ptr);
HeaderData.AddrSize = data.getU8(offset_ptr);
HeaderData.SegSize = data.getU8(offset_ptr);
// Perform basic validation of the header fields.
if (!data.isValidOffsetForDataOfSize(Offset, HeaderData.Length) ||
(HeaderData.AddrSize != 4 && HeaderData.AddrSize != 8)) {
clear();
return false;
}
// The first tuple following the header in each set begins at an offset
// that is a multiple of the size of a single tuple (that is, twice the
// size of an address). The header is padded, if necessary, to the
// appropriate boundary.
const uint32_t header_size = *offset_ptr - Offset;
const uint32_t tuple_size = HeaderData.AddrSize * 2;
uint32_t first_tuple_offset = 0;
while (first_tuple_offset < header_size)
first_tuple_offset += tuple_size;
*offset_ptr = Offset + first_tuple_offset;
Descriptor arangeDescriptor;
static_assert(sizeof(arangeDescriptor.Address) ==
sizeof(arangeDescriptor.Length),
"Different datatypes for addresses and sizes!");
assert(sizeof(arangeDescriptor.Address) >= HeaderData.AddrSize);
while (data.isValidOffset(*offset_ptr)) {
arangeDescriptor.Address = data.getUnsigned(offset_ptr, HeaderData.AddrSize);
arangeDescriptor.Length = data.getUnsigned(offset_ptr, HeaderData.AddrSize);
// Each set of tuples is terminated by a 0 for the address and 0
// for the length.
if (arangeDescriptor.Address || arangeDescriptor.Length)
ArangeDescriptors.push_back(arangeDescriptor);
else
break; // We are done if we get a zero address and length
}
return !ArangeDescriptors.empty();
}
return false;
}
void DWARFDebugArangeSet::dump(raw_ostream &OS) const {
OS << format("Address Range Header: length = 0x%8.8x, version = 0x%4.4x, ",
HeaderData.Length, HeaderData.Version)
<< format("cu_offset = 0x%8.8x, addr_size = 0x%2.2x, seg_size = 0x%2.2x\n",
HeaderData.CuOffset, HeaderData.AddrSize, HeaderData.SegSize);
const uint32_t hex_width = HeaderData.AddrSize * 2;
for (const auto &Desc : ArangeDescriptors) {
OS << format("[0x%*.*" PRIx64 " -", hex_width, hex_width, Desc.Address)
<< format(" 0x%*.*" PRIx64 ")\n",
hex_width, hex_width, Desc.getEndAddress());
}
}