llvm-6502/lib/DebugInfo/DWARFDebugRangeList.cpp
Alexey Samsonov eceb5b9977 Add basic support for .debug_ranges section to LLVM's DebugInfo library.
This section (introduced in DWARF-3) is used to define instruction address
ranges for functions that are not contiguous and can't be described
by low_pc/high_pc attributes (this is the usual case for inlined subroutines).
The patch is the first step to support fetching complete inlining info from DWARF.

Reviewed by Benjamin Kramer.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@162657 91177308-0d34-0410-b5e6-96231b3b80d8
2012-08-27 07:17:47 +00:00

59 lines
1.9 KiB
C++

//===-- DWARFDebugRangesList.cpp ------------------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "DWARFDebugRangeList.h"
#include "llvm/Support/Format.h"
#include "llvm/Support/raw_ostream.h"
using namespace llvm;
void DWARFDebugRangeList::clear() {
Offset = -1U;
AddressSize = 0;
Entries.clear();
}
bool DWARFDebugRangeList::extract(DataExtractor data, uint32_t *offset_ptr) {
clear();
if (!data.isValidOffset(*offset_ptr))
return false;
AddressSize = data.getAddressSize();
if (AddressSize != 4 && AddressSize != 8)
return false;
Offset = *offset_ptr;
while (true) {
RangeListEntry entry;
uint32_t prev_offset = *offset_ptr;
entry.StartAddress = data.getAddress(offset_ptr);
entry.EndAddress = data.getAddress(offset_ptr);
// Check that both values were extracted correctly.
if (*offset_ptr != prev_offset + 2 * AddressSize) {
clear();
return false;
}
// The end of any given range list is marked by an end of list entry,
// which consists of a 0 for the beginning address offset
// and a 0 for the ending address offset.
if (entry.StartAddress == 0 && entry.EndAddress == 0)
break;
Entries.push_back(entry);
}
return true;
}
void DWARFDebugRangeList::dump(raw_ostream &OS) const {
for (int i = 0, n = Entries.size(); i != n; ++i) {
const char *format_str = (AddressSize == 4) ? "%08x %08x %08x\n"
: "%08x %016x %016x\n";
OS << format(format_str, Offset, Entries[i].StartAddress,
Entries[i].EndAddress);
}
OS << format("%08x <End of list>\n", Offset);
}