From cd5da94d80b2b0f2bdb2d0157e24705a4cbd2a4e Mon Sep 17 00:00:00 2001 From: Pavel Labath Date: Fri, 20 Dec 2019 09:42:37 +0100 Subject: [PATCH] [lldb/DWARF] Fix mixed v4+v5 location lists 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 --- lldb/include/lldb/Expression/DWARFExpression.h | 9 -- lldb/source/Expression/DWARFExpression.cpp | 35 +---- .../SymbolFile/DWARF/DWARFDebugInfoEntry.cpp | 6 +- lldb/source/Plugins/SymbolFile/DWARF/DWARFUnit.cpp | 16 +++ lldb/source/Plugins/SymbolFile/DWARF/DWARFUnit.h | 7 + .../Plugins/SymbolFile/DWARF/SymbolFileDWARF.cpp | 16 +-- .../Plugins/SymbolFile/DWARF/SymbolFileDWARF.h | 6 - .../SymbolFile/DWARF/SymbolFileDWARFDwo.cpp | 7 - .../Plugins/SymbolFile/DWARF/SymbolFileDWARFDwo.h | 3 - .../SymbolFile/DWARF/debug_loc_and_loclists.s | 154 +++++++++++++++++++++ 10 files changed, 184 insertions(+), 75 deletions(-) create mode 100644 lldb/test/Shell/SymbolFile/DWARF/debug_loc_and_loclists.s diff --git a/lldb/include/lldb/Expression/DWARFExpression.h b/lldb/include/lldb/Expression/DWARFExpression.h index 1e32957..bfae142 100644 --- a/lldb/include/lldb/Expression/DWARFExpression.h +++ b/lldb/include/lldb/Expression/DWARFExpression.h @@ -34,15 +34,6 @@ namespace lldb_private { /// location expression or a location list and interprets it. class DWARFExpression { public: - enum LocationListFormat : uint8_t { - NonLocationList, // Not a location list - RegularLocationList, // Location list format used in non-split dwarf files - SplitDwarfLocationList, // Location list format used in pre-DWARF v5 split - // dwarf files (.debug_loc.dwo) - LocLists, // Location list format used in DWARF v5 - // (.debug_loclists/.debug_loclists.dwo). - }; - DWARFExpression(); /// Constructor diff --git a/lldb/source/Expression/DWARFExpression.cpp b/lldb/source/Expression/DWARFExpression.cpp index c67e35b..69c8464 100644 --- a/lldb/source/Expression/DWARFExpression.cpp +++ b/lldb/source/Expression/DWARFExpression.cpp @@ -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 -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_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_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 loctable_up = GetLocationTable( - m_dwarf_cu->GetSymbolFileDWARF().GetLocationListFormat(), m_data); - if (!loctable_up) - return; + std::unique_ptr 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 loctable_up = GetLocationTable( - m_dwarf_cu->GetSymbolFileDWARF().GetLocationListFormat(), m_data); - if (!loctable_up) - return llvm::None; + std::unique_ptr loctable_up = + m_dwarf_cu->GetLocationTable(m_data); llvm::Optional result; uint64_t offset = 0; auto lookup_addr = diff --git a/lldb/source/Plugins/SymbolFile/DWARF/DWARFDebugInfoEntry.cpp b/lldb/source/Plugins/SymbolFile/DWARF/DWARFDebugInfoEntry.cpp index 5612c59..5b95912 100644 --- a/lldb/source/Plugins/SymbolFile/DWARF/DWARFDebugInfoEntry.cpp +++ b/lldb/source/Plugins/SymbolFile/DWARF/DWARFDebugInfoEntry.cpp @@ -344,7 +344,7 @@ bool DWARFDebugInfoEntry::GetDIENamesAndRanges( *frame_base = DWARFExpression( module, DataExtractor(data, block_offset, block_length), cu); } else { - DataExtractor data = dwarf.DebugLocData(); + DataExtractor data = cu->GetLocationData(); const dw_offset_t offset = form_value.Unsigned(); if (data.ValidOffset(offset)) { data = DataExtractor(data, offset, data.GetByteSize() - offset); @@ -478,8 +478,6 @@ void DWARFDebugInfoEntry::DumpAttribute( s.PutCString("( "); - SymbolFileDWARF &dwarf = cu->GetSymbolFileDWARF(); - // Check to see if we have any special attribute formatters switch (attr) { case DW_AT_stmt_list: @@ -509,7 +507,7 @@ void DWARFDebugInfoEntry::DumpAttribute( // We have a location list offset as the value that is the offset into // the .debug_loc section that describes the value over it's lifetime uint64_t debug_loc_offset = form_value.Unsigned(); - DWARFExpression::PrintDWARFLocationList(s, cu, dwarf.DebugLocData(), + DWARFExpression::PrintDWARFLocationList(s, cu, cu->GetLocationData(), debug_loc_offset); } } break; diff --git a/lldb/source/Plugins/SymbolFile/DWARF/DWARFUnit.cpp b/lldb/source/Plugins/SymbolFile/DWARF/DWARFUnit.cpp index 32f0f89..dcb38da 100644 --- a/lldb/source/Plugins/SymbolFile/DWARF/DWARFUnit.cpp +++ b/lldb/source/Plugins/SymbolFile/DWARF/DWARFUnit.cpp @@ -462,6 +462,22 @@ void DWARFUnit::SetLoclistsBase(dw_addr_t loclists_base) { } } +std::unique_ptr +DWARFUnit::GetLocationTable(const DataExtractor &data) const { + llvm::DWARFDataExtractor llvm_data( + toStringRef(data.GetData()), + data.GetByteOrder() == lldb::eByteOrderLittle, data.GetAddressByteSize()); + + if (m_is_dwo || GetVersion() >= 5) + return std::make_unique(llvm_data, GetVersion()); + return std::make_unique(llvm_data); +} + +const DWARFDataExtractor &DWARFUnit::GetLocationData() const { + return GetVersion() >= 5 ? GetSymbolFileDWARF().get_debug_loclists_data() + : GetSymbolFileDWARF().get_debug_loc_data(); +} + void DWARFUnit::SetRangesBase(dw_addr_t ranges_base) { m_ranges_base = ranges_base; diff --git a/lldb/source/Plugins/SymbolFile/DWARF/DWARFUnit.h b/lldb/source/Plugins/SymbolFile/DWARF/DWARFUnit.h index 5e94dc1..6bee4ab 100644 --- a/lldb/source/Plugins/SymbolFile/DWARF/DWARFUnit.h +++ b/lldb/source/Plugins/SymbolFile/DWARF/DWARFUnit.h @@ -243,6 +243,13 @@ public: return *Offset + m_loclists_base; } + /// Return the location table for parsing the given location list data. The + /// format is chosen according to the unit type. Never returns null. + std::unique_ptr + GetLocationTable(const lldb_private::DataExtractor &data) const; + + const lldb_private::DWARFDataExtractor &GetLocationData() const; + protected: DWARFUnit(SymbolFileDWARF &dwarf, lldb::user_id_t uid, const DWARFUnitHeader &header, diff --git a/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.cpp b/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.cpp index 53339ea..0792260 100644 --- a/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.cpp +++ b/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.cpp @@ -597,13 +597,6 @@ void SymbolFileDWARF::LoadSectionData(lldb::SectionType sect_type, m_objfile_sp->ReadSectionData(section_sp.get(), data); } -const DWARFDataExtractor &SymbolFileDWARF::DebugLocData() { - const DWARFDataExtractor &debugLocData = get_debug_loc_data(); - if (debugLocData.GetByteSize() > 0) - return debugLocData; - return get_debug_loclists_data(); -} - const DWARFDataExtractor &SymbolFileDWARF::get_debug_loc_data() { return GetCachedSectionData(eSectionTypeDWARFDebugLoc, m_data_debug_loc); } @@ -3361,7 +3354,7 @@ VariableSP SymbolFileDWARF::ParseVariableDIE(const SymbolContext &sc, module, DataExtractor(data, block_offset, block_length), die.GetCU()); } else { - DataExtractor data = DebugLocData(); + DataExtractor data = die.GetCU()->GetLocationData(); dw_offset_t offset = form_value.Unsigned(); if (form_value.Form() == DW_FORM_loclistx) offset = die.GetCU()->GetLoclistOffset(offset).getValueOr(-1); @@ -3978,13 +3971,6 @@ SymbolFileDWARFDebugMap *SymbolFileDWARF::GetDebugMapSymfile() { return m_debug_map_symfile; } -DWARFExpression::LocationListFormat -SymbolFileDWARF::GetLocationListFormat() const { - if (m_data_debug_loclists.m_data.GetByteSize() > 0) - return DWARFExpression::LocLists; - return DWARFExpression::RegularLocationList; -} - SymbolFileDWARFDwp *SymbolFileDWARF::GetDwpSymbolFile() { llvm::call_once(m_dwp_symfile_once_flag, [this]() { ModuleSpec module_spec; diff --git a/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.h b/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.h index bf9a6e5..f816dd7 100644 --- a/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.h +++ b/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.h @@ -21,7 +21,6 @@ #include "lldb/Core/UniqueCStringMap.h" #include "lldb/Core/dwarf.h" -#include "lldb/Expression/DWARFExpression.h" #include "lldb/Symbol/DebugMacros.h" #include "lldb/Symbol/SymbolContext.h" #include "lldb/Symbol/SymbolFile.h" @@ -236,8 +235,6 @@ public: DWARFDebugRanges *GetDebugRanges(); - const lldb_private::DWARFDataExtractor &DebugLocData(); - static bool SupportedVersion(uint16_t version); DWARFDIE @@ -260,9 +257,6 @@ public: virtual lldb::CompUnitSP ParseCompileUnit(DWARFCompileUnit &dwarf_cu); - virtual lldb_private::DWARFExpression::LocationListFormat - GetLocationListFormat() const; - lldb::ModuleSP GetExternalModule(lldb_private::ConstString name); typedef std::map diff --git a/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARFDwo.cpp b/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARFDwo.cpp index 331417fe..f75f06f 100644 --- a/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARFDwo.cpp +++ b/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARFDwo.cpp @@ -137,13 +137,6 @@ SymbolFileDWARF &SymbolFileDWARFDwo::GetBaseSymbolFile() { return m_base_dwarf_cu.GetSymbolFileDWARF(); } -DWARFExpression::LocationListFormat -SymbolFileDWARFDwo::GetLocationListFormat() const { - return m_base_dwarf_cu.GetVersion() >= 5 - ? DWARFExpression::LocLists - : DWARFExpression::SplitDwarfLocationList; -} - llvm::Expected SymbolFileDWARFDwo::GetTypeSystemForLanguage(LanguageType language) { return GetBaseSymbolFile().GetTypeSystemForLanguage(language); diff --git a/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARFDwo.h b/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARFDwo.h index 641fd1f..0855dba 100644 --- a/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARFDwo.h +++ b/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARFDwo.h @@ -35,9 +35,6 @@ public: DWARFUnit * GetDWARFCompileUnit(lldb_private::CompileUnit *comp_unit) override; - lldb_private::DWARFExpression::LocationListFormat - GetLocationListFormat() const override; - size_t GetObjCMethodDIEOffsets(lldb_private::ConstString class_name, DIEArray &method_die_offsets) override; diff --git a/lldb/test/Shell/SymbolFile/DWARF/debug_loc_and_loclists.s b/lldb/test/Shell/SymbolFile/DWARF/debug_loc_and_loclists.s new file mode 100644 index 0000000..05bccbe --- /dev/null +++ b/lldb/test/Shell/SymbolFile/DWARF/debug_loc_and_loclists.s @@ -0,0 +1,154 @@ +# Test that we can handle DWARF 4 and 5 location lists in the same object file +# (but different compile units). + +# REQUIRES: x86 + +# RUN: llvm-mc -triple=x86_64-pc-linux -filetype=obj %s > %t +# RUN: %lldb %t -o "image lookup -v -s loc" -o "image lookup -v -s loclists" \ +# RUN: -o exit | FileCheck %s + + +# CHECK-LABEL: image lookup -v -s loc +# CHECK: Variable: {{.*}}, name = "x0", type = "int", location = DW_OP_reg5 RDI, + +# CHECK-LABEL: image lookup -v -s loclists +# CHECK: Variable: {{.*}}, name = "x1", type = "int", location = DW_OP_reg0 RAX, + + +loc: + nop +.Lloc_end: + +loclists: + nop +.Lloclists_end: + + .section .debug_loc,"",@progbits +.Lloc_list: + .quad loc-loc + .quad .Lloc_end-loc + .short 1 + .byte 85 # super-register DW_OP_reg5 + .quad 0 + .quad 0 + + .section .debug_loclists,"",@progbits + .long .Ldebug_loclist_table_end0-.Ldebug_loclist_table_start0 # Length +.Ldebug_loclist_table_start0: + .short 5 # Version + .byte 8 # Address size + .byte 0 # Segment selector size + .long 0 # Offset entry count + +.Lloclists_list: + .byte 4 # DW_LLE_offset_pair + .uleb128 loclists-loclists + .uleb128 .Lloclists_end-loclists + .uleb128 1 + .byte 80 # super-register DW_OP_reg0 + .byte 0 # DW_LLE_end_of_list +.Ldebug_loclist_table_end0: + + .section .debug_abbrev,"",@progbits + .byte 1 # Abbreviation Code + .byte 17 # DW_TAG_compile_unit + .byte 1 # DW_CHILDREN_yes + .byte 37 # DW_AT_producer + .byte 8 # DW_FORM_string + .byte 19 # DW_AT_language + .byte 5 # DW_FORM_data2 + .byte 17 # DW_AT_low_pc + .byte 1 # DW_FORM_addr + .byte 18 # DW_AT_high_pc + .byte 6 # DW_FORM_data4 + .byte 0 # EOM(1) + .byte 0 # EOM(2) + .byte 2 # Abbreviation Code + .byte 46 # DW_TAG_subprogram + .byte 1 # DW_CHILDREN_yes + .byte 17 # DW_AT_low_pc + .byte 1 # DW_FORM_addr + .byte 18 # DW_AT_high_pc + .byte 6 # DW_FORM_data4 + .byte 3 # DW_AT_name + .byte 8 # DW_FORM_string + .byte 73 # DW_AT_type + .byte 16 # DW_FORM_ref_addr + .byte 0 # EOM(1) + .byte 0 # EOM(2) + .byte 3 # Abbreviation Code + .byte 5 # DW_TAG_formal_parameter + .byte 0 # DW_CHILDREN_no + .byte 2 # DW_AT_location + .byte 23 # DW_FORM_sec_offset + .byte 3 # DW_AT_name + .byte 8 # DW_FORM_string + .byte 73 # DW_AT_type + .byte 16 # DW_FORM_ref_addr + .byte 0 # EOM(1) + .byte 0 # EOM(2) + .byte 4 # Abbreviation Code + .byte 36 # DW_TAG_base_type + .byte 0 # DW_CHILDREN_no + .byte 3 # DW_AT_name + .byte 8 # DW_FORM_string + .byte 62 # DW_AT_encoding + .byte 11 # DW_FORM_data1 + .byte 11 # DW_AT_byte_size + .byte 11 # DW_FORM_data1 + .byte 0 # EOM(1) + .byte 0 # EOM(2) + .byte 0 # EOM(3) + + .section .debug_info,"",@progbits + .long .Lloc_cu_end-.Lloc_cu_start # Length of Unit +.Lloc_cu_start: + .short 4 # DWARF version number + .long .debug_abbrev # Offset Into Abbrev. Section + .byte 8 # Address Size (in bytes) + .byte 1 # Abbrev [1] 0xb:0x50 DW_TAG_compile_unit + .asciz "Hand-written DWARF" # DW_AT_producer + .short 12 # DW_AT_language + .quad loc # DW_AT_low_pc + .long .Lloc_end-loc # DW_AT_high_pc + .byte 2 # Abbrev [2] 0x2a:0x29 DW_TAG_subprogram + .quad loc # DW_AT_low_pc + .long .Lloc_end-loc # DW_AT_high_pc + .asciz "loc" # DW_AT_name + .long .Lint # DW_AT_type + .byte 3 # Abbrev [3] DW_TAG_formal_parameter + .long .Lloc_list # DW_AT_location + .asciz "x0" # DW_AT_name + .long .Lint # DW_AT_type + .byte 0 # End Of Children Mark +.Lint: + .byte 4 # Abbrev [4] 0x53:0x7 DW_TAG_base_type + .asciz "int" # DW_AT_name + .byte 5 # DW_AT_encoding + .byte 4 # DW_AT_byte_size + .byte 0 # End Of Children Mark +.Lloc_cu_end: + + .long .Lloclists_cu_end-.Lloclists_cu_start # Length of Unit +.Lloclists_cu_start: + .short 5 # DWARF version number + .byte 1 # DWARF Unit Type + .byte 8 # Address Size (in bytes) + .long .debug_abbrev # Offset Into Abbrev. Section + .byte 1 # Abbrev [1] 0xb:0x50 DW_TAG_compile_unit + .asciz "Hand-written DWARF" # DW_AT_producer + .short 12 # DW_AT_language + .quad loclists # DW_AT_low_pc + .long .Lloclists_end-loclists # DW_AT_high_pc + .byte 2 # Abbrev [2] 0x2a:0x29 DW_TAG_subprogram + .quad loclists # DW_AT_low_pc + .long .Lloclists_end-loclists # DW_AT_high_pc + .asciz "loclists" # DW_AT_name + .long .Lint # DW_AT_type + .byte 3 # Abbrev [3] DW_TAG_formal_parameter + .long .Lloclists_list # DW_AT_location + .asciz "x1" # DW_AT_name + .long .Lint # DW_AT_type + .byte 0 # End Of Children Mark + .byte 0 # End Of Children Mark +.Lloclists_cu_end: -- 2.7.4