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[lldb/DWARF] Fix mixed v4+v5 location lists

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Summary:
Our code was expecting that a single (symbol) file contains only one
kind of location lists. This is not correct (on non-apple platforms, at
least) as a file can compile units with different dwarf versions.

This patch moves the deteremination of location list flavour down to the
compile unit level, fixing this problem. I have also tried to rougly
align the code with the llvm DWARFUnit. Fully matching the API is not
possible because of how lldb's DWARFExpression lives separately from the
rest of the DWARF code, but this is at least a step in the right
direction.

Reviewers: JDevlieghere, aprantl, clayborg

Subscribers: dblaikie, lldb-commits

Tags: #lldb

Differential Revision: https://reviews.llvm.org/D71751
This commit is contained in:
Pavel Labath
2019-12-20 09:42:37 +01:00
parent 9bb01efa49
commit cd5da94d80
10 changed files with 184 additions and 75 deletions
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35
lldb/source/Expression/DWARFExpression.cpp
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@@ -54,29 +54,6 @@ ReadAddressFromDebugAddrSection(const DWARFUnit *dwarf_cu,
return LLDB_INVALID_ADDRESS;
}
/// Return the location list parser for the given format.
static std::unique_ptr<llvm::DWARFLocationTable>
GetLocationTable(DWARFExpression::LocationListFormat format, const DataExtractor &data) {
llvm::DWARFDataExtractor llvm_data(
toStringRef(data.GetData()),
data.GetByteOrder() == lldb::eByteOrderLittle, data.GetAddressByteSize());
switch (format) {
case DWARFExpression::NonLocationList:
return nullptr;
// DWARF<=4 .debug_loc
case DWARFExpression::RegularLocationList:
return std::make_unique<llvm::DWARFDebugLoc>(llvm_data);
// Non-standard DWARF 4 extension (fission) .debug_loc.dwo
case DWARFExpression::SplitDwarfLocationList:
// DWARF 5 .debug_loclists(.dwo)
case DWARFExpression::LocLists:
return std::make_unique<llvm::DWARFDebugLoclists>(
llvm_data, format == DWARFExpression::LocLists ? 5 : 4);
}
llvm_unreachable("Invalid LocationListFormat!");
}
// DWARFExpression constructor
DWARFExpression::DWARFExpression()
: m_module_wp(), m_data(), m_dwarf_cu(nullptr),
@@ -157,10 +134,8 @@ void DWARFExpression::GetDescription(Stream *s, lldb::DescriptionLevel level,
if (IsLocationList()) {
// We have a location list
lldb::offset_t offset = 0;
std::unique_ptr<llvm::DWARFLocationTable> loctable_up = GetLocationTable(
m_dwarf_cu->GetSymbolFileDWARF().GetLocationListFormat(), m_data);
if (!loctable_up)
return;
std::unique_ptr<llvm::DWARFLocationTable> loctable_up =
m_dwarf_cu->GetLocationTable(m_data);
llvm::MCRegisterInfo *MRI = abi ? &abi->GetMCRegisterInfo() : nullptr;
@@ -2812,10 +2787,8 @@ DWARFExpression::GetLocationExpression(addr_t load_function_start,
addr_t addr) const {
Log *log = GetLogIfAllCategoriesSet(LIBLLDB_LOG_EXPRESSIONS);
std::unique_ptr<llvm::DWARFLocationTable> loctable_up = GetLocationTable(
m_dwarf_cu->GetSymbolFileDWARF().GetLocationListFormat(), m_data);
if (!loctable_up)
return llvm::None;
std::unique_ptr<llvm::DWARFLocationTable> loctable_up =
m_dwarf_cu->GetLocationTable(m_data);
llvm::Optional<DataExtractor> result;
uint64_t offset = 0;
auto lookup_addr =