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+ make use of .debug_aranges section for faster name search when generating stack backtraces

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git-svn-id: trunk@33470 -
This commit is contained in:
florian 2016-04-10 12:21:35 +00:00
parent fb87b6bc9c
commit a7346b2f9d
1 changed files with 121 additions and 7 deletions
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128
rtl/inc/lnfodwrf.pp
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@ -83,7 +83,10 @@ var
{ the offset and size of the DWARF debug_info section in the file }
Dwarf_Debug_Info_Section_Offset,
Dwarf_Debug_Info_Section_Size,
{ the offset and size of the DWARF debug_abbrev section in the file }
{ the offset and size of the DWARF debug_aranges section in the file }
Dwarf_Debug_Aranges_Section_Offset,
Dwarf_Debug_Aranges_Section_Size,
{ the offset and size of the DWARF debug_abbrev section in the file }
Dwarf_Debug_Abbrev_Section_Offset,
Dwarf_Debug_Abbrev_Section_Size : longint;
@ -185,6 +188,25 @@ type
address_size : Byte;
end;
TDebugArangesHeader64 = packed record
magic : DWord;
unit_length : QWord;
version : Word;
debug_info_offset : QWord;
address_size : Byte;
segment_size : Byte;
padding : DWord;
end;
TDebugArangesHeader32= packed record
unit_length : DWord;
version : Word;
debug_info_offset : DWord;
address_size : Byte;
segment_size : Byte;
padding : DWord;
end;
{---------------------------------------------------------------------------
I/O utility functions
---------------------------------------------------------------------------}
@ -249,13 +271,15 @@ begin
e.processaddress:=ptruint(baseaddr)-e.processaddress;
if FindExeSection(e,'.debug_line',Dwarf_Debug_Line_Section_offset,dwarf_Debug_Line_Section_size) and
FindExeSection(e,'.debug_info',Dwarf_Debug_Info_Section_offset,dwarf_Debug_Info_Section_size) and
FindExeSection(e,'.debug_abbrev',Dwarf_Debug_Abbrev_Section_offset,dwarf_Debug_Abbrev_Section_size) then
FindExeSection(e,'.debug_abbrev',Dwarf_Debug_Abbrev_Section_offset,dwarf_Debug_Abbrev_Section_size) and
FindExeSection(e,'.debug_aranges',Dwarf_Debug_Aranges_Section_offset,dwarf_Debug_Aranges_Section_size) then
begin
lastopendwarf:=true;
OpenDwarf:=true;
DEBUG_WRITELN('.debug_line starts at offset $',hexstr(Dwarf_Debug_Line_Section_offset,8),' with a size of ',Dwarf_Debug_Line_Section_Size,' Bytes');
DEBUG_WRITELN('.debug_info starts at offset $',hexstr(Dwarf_Debug_Info_Section_offset,8),' with a size of ',Dwarf_Debug_Info_Section_Size,' Bytes');
DEBUG_WRITELN('.debug_abbrev starts at offset $',hexstr(Dwarf_Debug_Abbrev_Section_offset,8),' with a size of ',Dwarf_Debug_Abbrev_Section_Size,' Bytes');
DEBUG_WRITELN('.debug_aranges starts at offset $',hexstr(Dwarf_Debug_Aranges_Section_offset,8),' with a size of ',Dwarf_Debug_Aranges_Section_Size,' Bytes');
end
else
CloseExeFile(e);
@ -873,11 +897,72 @@ procedure ReadAbbrevTable;
end;
function ParseCompilationUnitForDebugInfoOffset(const addr : PtrUInt; const file_offset : QWord;
var debug_info_offset : QWord; var found : Boolean) : QWord;
var
{ we need both headers on the stack, although we only use the 64 bit one internally }
header64 : TDebugArangesHeader64;
header32 : TDebugArangesHeader32;
isdwarf64 : boolean;
temp_length : DWord;
unit_length : QWord;
arange_start, arange_size: PtrUInt;
begin
found := false;
ReadNext(temp_length, sizeof(temp_length));
if (temp_length <> $ffffffff) then begin
unit_length := temp_length + sizeof(temp_length)
end else begin
ReadNext(unit_length, sizeof(unit_length));
inc(unit_length, 12);
end;
ParseCompilationUnitForDebugInfoOffset := file_offset + unit_length;
Init(file_offset, unit_length);
DEBUG_WRITELN('Unit length: ', unit_length);
if (temp_length <> $ffffffff) then
begin
DEBUG_WRITELN('32 bit DWARF detected');
ReadNext(header32, sizeof(header32));
header64.magic := $ffffffff;
header64.unit_length := header32.unit_length;
header64.version := header32.version;
header64.debug_info_offset := header32.debug_info_offset;
header64.address_size := header32.address_size;
header64.segment_size := header32.segment_size;
isdwarf64:=false;
end
else
begin
DEBUG_WRITELN('64 bit DWARF detected');
ReadNext(header64, sizeof(header64));
isdwarf64:=true;
end;
DEBUG_WRITELN('debug_info_offset: ',header64.debug_info_offset);
arange_start:=ReadAddress;
arange_size:=ReadAddress;
while not((arange_start=0) and (arange_size=0)) and (not found) do
begin
if (addr>=arange_start) and (addr<=arange_start+arange_size) then
begin
found:=true;
debug_info_offset:=header64.debug_info_offset;
DEBUG_WRITELN('Matching aranges entry $',hexStr(arange_start,header64.address_size*2),', $',hexStr(arange_size,header64.address_size*2));
end;
arange_start:=ReadAddress;
arange_size:=ReadAddress;
end;
end;
function ParseCompilationUnitForFunctionName(const addr : PtrUInt; const file_offset : QWord;
var func : String; var found : Boolean) : QWord;
var
state : TMachineState;
{ we need both headers on the stack, although we only use the 64 bit one internally }
header64 : TDebugInfoProgramHeader64;
header32 : TDebugInfoProgramHeader32;
@ -1081,10 +1166,10 @@ end;
function GetLineInfo(addr : ptruint; var func, source : string; var line : longint) : boolean;
var
current_offset : QWord;
end_offset : QWord;
current_offset,
end_offset, debug_info_offset_from_aranges : QWord;
found : Boolean;
found, found_aranges : Boolean;
begin
func := '';
@ -1106,11 +1191,40 @@ begin
source, line, found);
end;
current_offset := Dwarf_Debug_Aranges_Section_Offset;
end_offset := Dwarf_Debug_Aranges_Section_Offset + Dwarf_Debug_Aranges_Section_Size;
found_aranges := false;
while (current_offset < end_offset) and (not found_aranges) do begin
Init(current_offset, end_offset - current_offset);
current_offset := ParseCompilationUnitForDebugInfoOffset(addr, current_offset, debug_info_offset_from_aranges, found_aranges);
end;
{ no function name found yet }
found := false;
if found_aranges then
begin
DEBUG_WRITELN('Found .debug_info offset $',hexstr(debug_info_offset_from_aranges,8),' from .debug_aranges');
current_offset := Dwarf_Debug_Info_Section_Offset + debug_info_offset_from_aranges;
end_offset := Dwarf_Debug_Info_Section_Offset + debug_info_offset_from_aranges + Dwarf_Debug_Info_Section_Size;
DEBUG_WRITELN('Reading .debug_info at section offset $',hexStr(current_offset-Dwarf_Debug_Info_Section_Offset,16));
Init(current_offset, end_offset - current_offset);
current_offset := ParseCompilationUnitForFunctionName(addr, current_offset, func, found);
if found then
DEBUG_WRITELN('Found .debug_info entry by using .debug_aranges information');
end
else
DEBUG_WRITELN('No .debug_info offset found from .debug_aranges');
current_offset := Dwarf_Debug_Info_Section_Offset;
end_offset := Dwarf_Debug_Info_Section_Offset + Dwarf_Debug_Info_Section_Size;
found := false;
while (current_offset < end_offset) and (not found) do begin
DEBUG_WRITELN('Reading .debug_info at section offset $',hexStr(current_offset-Dwarf_Debug_Info_Section_Offset,16));
Init(current_offset, end_offset - current_offset);
current_offset := ParseCompilationUnitForFunctionName(addr, current_offset, func, found);
end;