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Diffstat (limited to 'source/Plugins/SymbolFile/DWARF/DWARFDebugArangeSet.cpp')
| -rw-r--r-- | source/Plugins/SymbolFile/DWARF/DWARFDebugArangeSet.cpp | 274 |
1 files changed, 274 insertions, 0 deletions
diff --git a/source/Plugins/SymbolFile/DWARF/DWARFDebugArangeSet.cpp b/source/Plugins/SymbolFile/DWARF/DWARFDebugArangeSet.cpp new file mode 100644 index 000000000000..b1eb27299efb --- /dev/null +++ b/source/Plugins/SymbolFile/DWARF/DWARFDebugArangeSet.cpp @@ -0,0 +1,274 @@ +//===-- DWARFDebugArangeSet.cpp ---------------------------------*- C++ -*-===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// + +#include "DWARFDebugArangeSet.h" + +#include <assert.h> +#include "lldb/Core/Stream.h" +#include "SymbolFileDWARF.h" + +using namespace lldb_private; + +DWARFDebugArangeSet::DWARFDebugArangeSet() : + m_offset(DW_INVALID_OFFSET), + m_header(), + m_arange_descriptors() +{ + m_header.length = 0; + m_header.version = 0; + m_header.cu_offset = 0; + m_header.addr_size = 0; + m_header.seg_size = 0; +} + +void +DWARFDebugArangeSet::Clear() +{ + m_offset = DW_INVALID_OFFSET; + m_header.length = 0; + m_header.version = 0; + m_header.cu_offset = 0; + m_header.addr_size = 0; + m_header.seg_size = 0; + m_arange_descriptors.clear(); +} + +void +DWARFDebugArangeSet::SetHeader +( + uint16_t version, + uint32_t cu_offset, + uint8_t addr_size, + uint8_t seg_size +) +{ + m_header.version = version; + m_header.cu_offset = cu_offset; + m_header.addr_size = addr_size; + m_header.seg_size = seg_size; +} + +void +DWARFDebugArangeSet::Compact() +{ + if (m_arange_descriptors.empty()) + return; + + // Iterate through all arange descriptors and combine any ranges that + // overlap or have matching boundaries. The m_arange_descriptors are assumed + // to be in ascending order after being built by adding descriptors + // using the AddDescriptor method. + uint32_t i = 0; + while (i + 1 < m_arange_descriptors.size()) + { + if (m_arange_descriptors[i].end_address() >= m_arange_descriptors[i+1].address) + { + // The current range ends at or exceeds the start of the next address range. + // Compute the max end address between the two and use that to make the new + // length. + const dw_addr_t max_end_addr = std::max(m_arange_descriptors[i].end_address(), m_arange_descriptors[i+1].end_address()); + m_arange_descriptors[i].length = max_end_addr - m_arange_descriptors[i].address; + // Now remove the next entry as it was just combined with the previous one. + m_arange_descriptors.erase(m_arange_descriptors.begin()+i+1); + } + else + { + // Discontiguous address range, just proceed to the next one. + ++i; + } + } +} +//---------------------------------------------------------------------- +// Compare function DWARFDebugArangeSet::Descriptor structures +//---------------------------------------------------------------------- +static bool DescriptorLessThan (const DWARFDebugArangeSet::Descriptor& range1, const DWARFDebugArangeSet::Descriptor& range2) +{ + return range1.address < range2.address; +} + +//---------------------------------------------------------------------- +// Add a range descriptor and keep things sorted so we can easily +// compact the ranges before being saved or used. +//---------------------------------------------------------------------- +void +DWARFDebugArangeSet::AddDescriptor(const DWARFDebugArangeSet::Descriptor& range) +{ + if (m_arange_descriptors.empty()) + { + m_arange_descriptors.push_back(range); + return; + } + + DescriptorIter end = m_arange_descriptors.end(); + DescriptorIter pos = lower_bound(m_arange_descriptors.begin(), end, range, DescriptorLessThan); + const dw_addr_t range_end_addr = range.end_address(); + if (pos != end) + { + const dw_addr_t found_end_addr = pos->end_address(); + if (range.address < pos->address) + { + if (range_end_addr < pos->address) + { + // Non-contiguous entries, add this one before the found entry + m_arange_descriptors.insert(pos, range); + } + else if (range_end_addr == pos->address) + { + // The top end of 'range' is the lower end of the entry + // pointed to by 'pos'. We can combine range with the + // entry we found by setting the starting address and + // increasing the length since they don't overlap. + pos->address = range.address; + pos->length += range.length; + } + else + { + // We can combine these two and make sure the largest end + // address is used to make end address. + pos->address = range.address; + pos->length = std::max(found_end_addr, range_end_addr) - pos->address; + } + } + else if (range.address == pos->address) + { + pos->length = std::max(pos->length, range.length); + } + } + else + { + // NOTE: 'pos' points to entry past the end which is ok for insert, + // don't use otherwise!!! + const dw_addr_t max_addr = m_arange_descriptors.back().end_address(); + if (max_addr < range.address) + { + // Non-contiguous entries, add this one before the found entry + m_arange_descriptors.insert(pos, range); + } + else if (max_addr == range.address) + { + m_arange_descriptors.back().length += range.length; + } + else + { + m_arange_descriptors.back().length = std::max(max_addr, range_end_addr) - m_arange_descriptors.back().address; + } + } +} + +bool +DWARFDebugArangeSet::Extract(const DataExtractor &data, lldb::offset_t *offset_ptr) +{ + if (data.ValidOffset(*offset_ptr)) + { + m_arange_descriptors.clear(); + m_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. + m_header.length = data.GetU32(offset_ptr); + m_header.version = data.GetU16(offset_ptr); + m_header.cu_offset = data.GetU32(offset_ptr); + m_header.addr_size = data.GetU8(offset_ptr); + m_header.seg_size = data.GetU8(offset_ptr); + + + // 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 - m_offset; + const uint32_t tuple_size = m_header.addr_size << 1; + uint32_t first_tuple_offset = 0; + while (first_tuple_offset < header_size) + first_tuple_offset += tuple_size; + + *offset_ptr = m_offset + first_tuple_offset; + + Descriptor arangeDescriptor; + + assert(sizeof(arangeDescriptor.address) == sizeof(arangeDescriptor.length)); + assert(sizeof(arangeDescriptor.address) >= m_header.addr_size); + + while (data.ValidOffset(*offset_ptr)) + { + arangeDescriptor.address = data.GetMaxU64(offset_ptr, m_header.addr_size); + arangeDescriptor.length = data.GetMaxU64(offset_ptr, m_header.addr_size); + + // Each set of tuples is terminated by a 0 for the address and 0 + // for the length. + if (arangeDescriptor.address || arangeDescriptor.length) + m_arange_descriptors.push_back(arangeDescriptor); + else + break; // We are done if we get a zero address and length + } + + return !m_arange_descriptors.empty(); + } + return false; +} + + +dw_offset_t +DWARFDebugArangeSet::GetOffsetOfNextEntry() const +{ + return m_offset + m_header.length + 4; +} + + +void +DWARFDebugArangeSet::Dump(Stream *s) const +{ + s->Printf("Address Range Header: length = 0x%8.8x, version = 0x%4.4x, cu_offset = 0x%8.8x, addr_size = 0x%2.2x, seg_size = 0x%2.2x\n", + m_header.length ,m_header.version, m_header.cu_offset, m_header.addr_size, m_header.seg_size); + + const uint32_t hex_width = m_header.addr_size * 2; + DescriptorConstIter pos; + DescriptorConstIter end = m_arange_descriptors.end(); + for (pos = m_arange_descriptors.begin(); pos != end; ++pos) + s->Printf("[0x%*.*" PRIx64 " - 0x%*.*" PRIx64 ")\n", + hex_width, hex_width, pos->address, + hex_width, hex_width, pos->end_address()); +} + + +class DescriptorContainsAddress +{ +public: + DescriptorContainsAddress (dw_addr_t address) : m_address(address) {} + bool operator() (const DWARFDebugArangeSet::Descriptor& desc) const + { + return (m_address >= desc.address) && (m_address < (desc.address + desc.length)); + } + private: + const dw_addr_t m_address; +}; + +dw_offset_t +DWARFDebugArangeSet::FindAddress(dw_addr_t address) const +{ + DescriptorConstIter end = m_arange_descriptors.end(); + DescriptorConstIter pos = std::find_if( m_arange_descriptors.begin(), end, // Range + DescriptorContainsAddress(address));// Predicate + if (pos != end) + return m_header.cu_offset; + + return DW_INVALID_OFFSET; +} |