Improve the handling of missing elf symtab and missing symbol sizes

* Generate artificial symbol names from eh_fame during symbol parsing so these symbols are already present when we calcualte the size of the symbols where 0 is specified. * Fix symbol size calculation for the last symbol in the file where it have to last until the end of the parent section. This is the re-commit of the original change after fixing some test failures on OSX. Differential revision: http://reviews.llvm.org/D16996 llvm-svn: 261205
llvm · Feb 18, 2016 · 6b63b14 · 6b63b14
1 parent a6560eb
commit 6b63b14
Showing 10 changed files with 149 additions and 150 deletions.
diff --git a/lldb/include/lldb/Core/RangeMap.h b/lldb/include/lldb/Core/RangeMap.h
@@ -1123,7 +1123,7 @@ namespace lldb_private {
         // Calculate the byte size of ranges with zero byte sizes by finding
         // the next entry with a base address > the current base address
         void
-        CalculateSizesOfZeroByteSizeRanges ()
+        CalculateSizesOfZeroByteSizeRanges (S full_size = 0)
         {
 #ifdef ASSERT_RANGEMAP_ARE_SORTED
             assert (IsSorted());
@@ -1148,6 +1148,8 @@ namespace lldb_private {
                             break;
                         }
                     }
+                    if (next == end && full_size > curr_base)
+                        pos->SetByteSize (full_size - curr_base);
                 }
             }
         }
@@ -1305,6 +1307,22 @@ namespace lldb_private {
             return nullptr;
         }
 
+        const Entry*
+        FindEntryStartsAt (B addr) const
+        {
+#ifdef ASSERT_RANGEMAP_ARE_SORTED
+            assert (IsSorted());
+#endif
+            if (!m_entries.empty())
+            {
+                auto begin = m_entries.begin(), end = m_entries.end();
+                auto pos = std::lower_bound (begin, end, Entry(addr, 1), BaseLessThan);
+                if (pos != end && pos->base == addr)
+                    return &(*pos);
+            }
+            return nullptr;
+        }
+
         Entry *
         Back()
         {

diff --git a/lldb/include/lldb/Symbol/DWARFCallFrameInfo.h b/lldb/include/lldb/Symbol/DWARFCallFrameInfo.h
@@ -73,6 +73,9 @@ class DWARFCallFrameInfo
     void
     GetFunctionAddressAndSizeVector (FunctionAddressAndSizeVector &function_info);
 
+    void
+    ForEachFDEEntries(const std::function<bool(lldb::addr_t, uint32_t, dw_offset_t)>& callback);
+
 private:
     enum
     {

diff --git a/lldb/include/lldb/Symbol/ObjectFile.h b/lldb/include/lldb/Symbol/ObjectFile.h
@@ -860,6 +860,7 @@ friend class lldb_private::Module;
     const lldb::addr_t m_memory_addr;
     std::unique_ptr<lldb_private::SectionList> m_sections_ap;
     std::unique_ptr<lldb_private::Symtab> m_symtab_ap;
+    uint32_t m_synthetic_symbol_idx;
 
     //------------------------------------------------------------------
     /// Sets the architecture for a module.  At present the architecture
@@ -873,7 +874,11 @@ friend class lldb_private::Module;
     ///     Returns \b true if the architecture was changed, \b
     ///     false otherwise.
     //------------------------------------------------------------------
-    bool SetModulesArchitecture (const ArchSpec &new_arch);
+    bool
+    SetModulesArchitecture (const ArchSpec &new_arch);
+
+    ConstString
+    GetNextSyntheticSymbolName();
 
 private:
     DISALLOW_COPY_AND_ASSIGN (ObjectFile);

diff --git a/lldb/include/lldb/Symbol/Symtab.h b/lldb/include/lldb/Symbol/Symtab.h
@@ -79,7 +79,7 @@ class Symtab
             size_t      FindAllSymbolsWithNameAndType (const ConstString &name, lldb::SymbolType symbol_type, Debug symbol_debug_type, Visibility symbol_visibility, std::vector<uint32_t>& symbol_indexes);
             size_t      FindAllSymbolsMatchingRexExAndType (const RegularExpression &regex, lldb::SymbolType symbol_type, Debug symbol_debug_type, Visibility symbol_visibility, std::vector<uint32_t>& symbol_indexes);
             Symbol *    FindFirstSymbolWithNameAndType (const ConstString &name, lldb::SymbolType symbol_type, Debug symbol_debug_type, Visibility symbol_visibility);
-            Symbol *    FindSymbolContainingFileAddress (lldb::addr_t file_addr, const uint32_t* indexes, uint32_t num_indexes);
+            Symbol *    FindSymbolAtFileAddress (lldb::addr_t file_addr);
             Symbol *    FindSymbolContainingFileAddress (lldb::addr_t file_addr);
             void        ForEachSymbolContainingFileAddress(lldb::addr_t file_addr, std::function<bool(Symbol *)> const &callback);
             size_t      FindFunctionSymbols (const ConstString &name, uint32_t name_type_mask, SymbolContextList& sc_list);

diff --git a/lldb/source/Plugins/ObjectFile/ELF/ObjectFileELF.cpp b/lldb/source/Plugins/ObjectFile/ELF/ObjectFileELF.cpp
@@ -2332,11 +2332,11 @@ ObjectFileELF::ParseSymbols (Symtab *symtab,
                 mangled.SetDemangledName( ConstString((demangled_name + suffix).str()) );
         }
 
-        // In ELF all symbol should have a valid size but it is not true for some code symbols
-        // coming from hand written assembly. As none of the code symbol should have 0 size we try
-        // to calculate the size for these symbols in the symtab with saying that their original
+        // In ELF all symbol should have a valid size but it is not true for some function symbols
+        // coming from hand written assembly. As none of the function symbol should have 0 size we
+        // try to calculate the size for these symbols in the symtab with saying that their original
         // size is not valid.
-        bool symbol_size_valid = symbol.st_size != 0 || symbol_type != eSymbolTypeCode;
+        bool symbol_size_valid = symbol.st_size != 0 || symbol.getType() != STT_FUNC;
 
         Symbol dc_symbol(
             i + start_id,       // ID is the original symbol table index.
@@ -2863,6 +2863,14 @@ ObjectFileELF::GetSymtab()
             }
         }
 
+        DWARFCallFrameInfo* eh_frame = GetUnwindTable().GetEHFrameInfo();
+        if (eh_frame)
+        {
+            if (m_symtab_ap == nullptr)
+                m_symtab_ap.reset(new Symtab(this));
+            ParseUnwindSymbols (m_symtab_ap.get(), eh_frame);
+        }
+
         // If we still don't have any symtab then create an empty instance to avoid do the section
         // lookup next time.
         if (m_symtab_ap == nullptr)
@@ -2892,57 +2900,64 @@ ObjectFileELF::GetSymtab()
     return m_symtab_ap.get();
 }
 
-Symbol *
-ObjectFileELF::ResolveSymbolForAddress(const Address& so_addr, bool verify_unique)
+void
+ObjectFileELF::ParseUnwindSymbols(Symtab *symbol_table, DWARFCallFrameInfo* eh_frame)
 {
-    if (!m_symtab_ap.get())
-        return nullptr; // GetSymtab() should be called first.
-
-    const SectionList *section_list = GetSectionList();
+    SectionList* section_list = GetSectionList();
     if (!section_list)
-        return nullptr;
+        return;
 
-    if (DWARFCallFrameInfo *eh_frame = GetUnwindTable().GetEHFrameInfo())
-    {
-        AddressRange range;
-        if (eh_frame->GetAddressRange (so_addr, range))
+    // First we save the new symbols into a separate list and add them to the symbol table after
+    // we colleced all symbols we want to add. This is neccessary because adding a new symbol
+    // invalidates the internal index of the symtab what causing the next lookup to be slow because
+    // it have to recalculate the index first.
+    std::vector<Symbol> new_symbols;
+
+    eh_frame->ForEachFDEEntries(
+        [this, symbol_table, section_list, &new_symbols](lldb::addr_t file_addr,
+                                                         uint32_t size,
+                                                         dw_offset_t) {
+        Symbol* symbol = symbol_table->FindSymbolAtFileAddress(file_addr);
+        if (symbol)
         {
-            const addr_t file_addr = range.GetBaseAddress().GetFileAddress();
-            Symbol * symbol = verify_unique ? m_symtab_ap->FindSymbolContainingFileAddress(file_addr) : nullptr;
-            if (symbol)
-                return symbol;
-
-            // Note that a (stripped) symbol won't be found by GetSymtab()...
-            lldb::SectionSP eh_sym_section_sp = section_list->FindSectionContainingFileAddress(file_addr);
-            if (eh_sym_section_sp.get())
+            if (!symbol->GetByteSizeIsValid())
             {
-                addr_t section_base = eh_sym_section_sp->GetFileAddress();
-                addr_t offset = file_addr - section_base;
-                uint64_t symbol_id = m_symtab_ap->GetNumSymbols();
-
+                symbol->SetByteSize(size);
+                symbol->SetSizeIsSynthesized(true);
+            }
+        }
+        else
+        {
+            SectionSP section_sp = section_list->FindSectionContainingFileAddress(file_addr);
+            if (section_sp)
+            {
+                addr_t offset = file_addr - section_sp->GetFileAddress();
+                const char* symbol_name = GetNextSyntheticSymbolName().GetCString();
+                uint64_t symbol_id = symbol_table->GetNumSymbols();
                 Symbol eh_symbol(
-                        symbol_id,            // Symbol table index.
-                        "???",                // Symbol name.
-                        false,                // Is the symbol name mangled?
-                        eSymbolTypeCode,      // Type of this symbol.
-                        true,                 // Is this globally visible?
-                        false,                // Is this symbol debug info?
-                        false,                // Is this symbol a trampoline?
-                        true,                 // Is this symbol artificial?
-                        eh_sym_section_sp,    // Section in which this symbol is defined or null.
-                        offset,               // Offset in section or symbol value.
-                        range.GetByteSize(),  // Size in bytes of this symbol.
-                        true,                 // Size is valid.
-                        false,                // Contains linker annotations?
-                        0);                   // Symbol flags.
-                if (symbol_id == m_symtab_ap->AddSymbol(eh_symbol))
-                    return m_symtab_ap->SymbolAtIndex(symbol_id);
+                        symbol_id,       // Symbol table index.
+                        symbol_name,     // Symbol name.
+                        false,           // Is the symbol name mangled?
+                        eSymbolTypeCode, // Type of this symbol.
+                        true,            // Is this globally visible?
+                        false,           // Is this symbol debug info?
+                        false,           // Is this symbol a trampoline?
+                        true,            // Is this symbol artificial?
+                        section_sp,      // Section in which this symbol is defined or null.
+                        offset,          // Offset in section or symbol value.
+                        0,               // Size:          Don't specify the size as an FDE can
+                        false,           // Size is valid: cover multiple symbols.
+                        false,           // Contains linker annotations?
+                        0);              // Symbol flags.
+                new_symbols.push_back(eh_symbol);
             }
         }
-    }
-    return nullptr;
-}
+        return true;
+    });
 
+    for (const Symbol& s : new_symbols)
+        symbol_table->AddSymbol(s);
+}
 
 bool
 ObjectFileELF::IsStripped ()

diff --git a/lldb/source/Plugins/ObjectFile/ELF/ObjectFileELF.h b/lldb/source/Plugins/ObjectFile/ELF/ObjectFileELF.h
@@ -150,9 +150,6 @@ class ObjectFileELF :
     lldb_private::Symtab *
     GetSymtab() override;
 
-    lldb_private::Symbol *
-    ResolveSymbolForAddress(const lldb_private::Address& so_addr, bool verify_unique) override;
-
     bool
     IsStripped () override;
 
@@ -349,6 +346,10 @@ class ObjectFileELF :
                            const ELFSectionHeaderInfo *rela_hdr,
                            lldb::user_id_t section_id);
 
+    void
+    ParseUnwindSymbols(lldb_private::Symtab *symbol_table,
+                       lldb_private::DWARFCallFrameInfo* eh_frame);
+
     /// Relocates debug sections
     unsigned
     RelocateDebugSections(const elf::ELFSectionHeader *rel_hdr, lldb::user_id_t rel_id);

diff --git a/lldb/source/Plugins/ObjectFile/Mach-O/ObjectFileMachO.cpp b/lldb/source/Plugins/ObjectFile/Mach-O/ObjectFileMachO.cpp
@@ -4518,7 +4518,6 @@ ObjectFileMachO::ParseSymtab ()
 
         if (function_starts_count > 0)
         {
-            char synthetic_function_symbol[PATH_MAX];
             uint32_t num_synthetic_function_symbols = 0;
             for (i=0; i<function_starts_count; ++i)
             {
@@ -4533,7 +4532,6 @@ ObjectFileMachO::ParseSymtab ()
                     num_syms = sym_idx + num_synthetic_function_symbols;
                     sym = symtab->Resize (num_syms);
                 }
-                uint32_t synthetic_function_symbol_idx = 0;
                 for (i=0; i<function_starts_count; ++i)
                 {
                     const FunctionStarts::Entry *func_start_entry = function_starts.GetEntryAtIndex (i);
@@ -4568,13 +4566,8 @@ ObjectFileMachO::ParseSymtab ()
                                 {
                                     symbol_byte_size = section_end_file_addr - symbol_file_addr;
                                 }
-                                snprintf (synthetic_function_symbol,
-                                          sizeof(synthetic_function_symbol),
-                                          "___lldb_unnamed_function%u$$%s",
-                                          ++synthetic_function_symbol_idx,
-                                          module_sp->GetFileSpec().GetFilename().GetCString());
                                 sym[sym_idx].SetID (synthetic_sym_id++);
-                                sym[sym_idx].GetMangled().SetDemangledName(ConstString(synthetic_function_symbol));
+                                sym[sym_idx].GetMangled().SetDemangledName(GetNextSyntheticSymbolName());
                                 sym[sym_idx].SetType (eSymbolTypeCode);
                                 sym[sym_idx].SetIsSynthetic (true);
                                 sym[sym_idx].GetAddressRef() = symbol_addr;

diff --git a/lldb/source/Symbol/DWARFCallFrameInfo.cpp b/lldb/source/Symbol/DWARFCallFrameInfo.cpp
@@ -899,3 +899,17 @@ DWARFCallFrameInfo::HandleCommonDwarfOpcode(uint8_t primary_opcode,
     }
     return false;
 }
+
+void
+DWARFCallFrameInfo::ForEachFDEEntries(
+    const std::function<bool(lldb::addr_t, uint32_t, dw_offset_t)>& callback)
+{
+    GetFDEIndex();
+
+    for (size_t i = 0, c = m_fde_index.GetSize(); i < c; ++i)
+    {
+        const FDEEntryMap::Entry& entry = m_fde_index.GetEntryRef(i);
+        if (!callback(entry.base, entry.size, entry.data))
+            break;
+    }
+}
diff --git a/lldb/source/Symbol/ObjectFile.cpp b/lldb/source/Symbol/ObjectFile.cpp
@@ -241,8 +241,7 @@ ObjectFile::ObjectFile (const lldb::ModuleSP &module_sp,
                         lldb::offset_t file_offset,
                         lldb::offset_t length,
                         const lldb::DataBufferSP& data_sp,
-                        lldb::offset_t data_offset
-) :
+                        lldb::offset_t data_offset) :
     ModuleChild (module_sp),
     m_file (),  // This file could be different from the original module's file
     m_type (eTypeInvalid),
@@ -254,7 +253,8 @@ ObjectFile::ObjectFile (const lldb::ModuleSP &module_sp,
     m_process_wp(),
     m_memory_addr (LLDB_INVALID_ADDRESS),
     m_sections_ap(),
-    m_symtab_ap ()
+    m_symtab_ap (),
+    m_synthetic_symbol_idx (0)
 {
     if (file_spec_ptr)
         m_file = *file_spec_ptr;
@@ -286,7 +286,8 @@ ObjectFile::ObjectFile (const lldb::ModuleSP &module_sp,
     m_process_wp (process_sp),
     m_memory_addr (header_addr),
     m_sections_ap(),
-    m_symtab_ap ()
+    m_symtab_ap (),
+    m_synthetic_symbol_idx (0)
 {
     if (header_data_sp)
         m_data.SetData (header_data_sp, 0, header_data_sp->GetByteSize());
@@ -653,3 +654,13 @@ ObjectFile::GetSymbolTypeFromName (llvm::StringRef name,
     }
     return symbol_type_hint;
 }
+
+ConstString
+ObjectFile::GetNextSyntheticSymbolName()
+{
+    StreamString ss;
+    ConstString file_name = GetModule()->GetFileSpec().GetFilename();
+    ss.Printf("___lldb_unnamed_symbol%u$$%s", ++m_synthetic_symbol_idx, file_name.GetCString());
+    return ConstString(ss.GetData());
+}
+