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Diffstat (limited to 'examples/python/diagnose_unwind.py')
| -rw-r--r-- | examples/python/diagnose_unwind.py | 313 |
1 files changed, 0 insertions, 313 deletions
diff --git a/examples/python/diagnose_unwind.py b/examples/python/diagnose_unwind.py deleted file mode 100644 index b90372970e5d..000000000000 --- a/examples/python/diagnose_unwind.py +++ /dev/null @@ -1,313 +0,0 @@ -# This implements the "diagnose-unwind" command, usually installed -# in the debug session like -# command script import lldb.diagnose -# it is used when lldb's backtrace fails -- it collects and prints -# information about the stack frames, and tries an alternate unwind -# algorithm, that will help to understand why lldb's unwind algorithm -# did not succeed. - -import optparse -import lldb -import re -import shlex - -# Print the frame number, pc, frame pointer, module UUID and function name -# Returns the SBModule that contains the PC, if it could be found - - -def backtrace_print_frame(target, frame_num, addr, fp): - process = target.GetProcess() - addr_for_printing = addr - addr_width = process.GetAddressByteSize() * 2 - if frame_num > 0: - addr = addr - 1 - - sbaddr = lldb.SBAddress() - try: - sbaddr.SetLoadAddress(addr, target) - module_description = "" - if sbaddr.GetModule(): - module_filename = "" - module_uuid_str = sbaddr.GetModule().GetUUIDString() - if module_uuid_str is None: - module_uuid_str = "" - if sbaddr.GetModule().GetFileSpec(): - module_filename = sbaddr.GetModule().GetFileSpec().GetFilename() - if module_filename is None: - module_filename = "" - if module_uuid_str != "" or module_filename != "": - module_description = '%s %s' % ( - module_filename, module_uuid_str) - except Exception: - print '%2d: pc==0x%-*x fp==0x%-*x' % (frame_num, addr_width, addr_for_printing, addr_width, fp) - return - - sym_ctx = target.ResolveSymbolContextForAddress( - sbaddr, lldb.eSymbolContextEverything) - if sym_ctx.IsValid() and sym_ctx.GetSymbol().IsValid(): - function_start = sym_ctx.GetSymbol().GetStartAddress().GetLoadAddress(target) - offset = addr - function_start - print '%2d: pc==0x%-*x fp==0x%-*x %s %s + %d' % (frame_num, addr_width, addr_for_printing, addr_width, fp, module_description, sym_ctx.GetSymbol().GetName(), offset) - else: - print '%2d: pc==0x%-*x fp==0x%-*x %s' % (frame_num, addr_width, addr_for_printing, addr_width, fp, module_description) - return sbaddr.GetModule() - -# A simple stack walk algorithm that follows the frame chain. -# Returns a two-element list; the first element is a list of modules -# seen and the second element is a list of addresses seen during the backtrace. - - -def simple_backtrace(debugger): - target = debugger.GetSelectedTarget() - process = target.GetProcess() - cur_thread = process.GetSelectedThread() - - initial_fp = cur_thread.GetFrameAtIndex(0).GetFP() - - # If the pseudoreg "fp" isn't recognized, on arm hardcode to r7 which is - # correct for Darwin programs. - if initial_fp == lldb.LLDB_INVALID_ADDRESS and target.triple[0:3] == "arm": - for reggroup in cur_thread.GetFrameAtIndex(1).registers: - if reggroup.GetName() == "General Purpose Registers": - for reg in reggroup: - if reg.GetName() == "r7": - initial_fp = int(reg.GetValue(), 16) - - module_list = [] - address_list = [cur_thread.GetFrameAtIndex(0).GetPC()] - this_module = backtrace_print_frame( - target, 0, cur_thread.GetFrameAtIndex(0).GetPC(), initial_fp) - print_stack_frame(process, initial_fp) - print "" - if this_module is not None: - module_list.append(this_module) - if cur_thread.GetNumFrames() < 2: - return [module_list, address_list] - - cur_fp = process.ReadPointerFromMemory(initial_fp, lldb.SBError()) - cur_pc = process.ReadPointerFromMemory( - initial_fp + process.GetAddressByteSize(), lldb.SBError()) - - frame_num = 1 - - while cur_pc != 0 and cur_fp != 0 and cur_pc != lldb.LLDB_INVALID_ADDRESS and cur_fp != lldb.LLDB_INVALID_ADDRESS: - address_list.append(cur_pc) - this_module = backtrace_print_frame(target, frame_num, cur_pc, cur_fp) - print_stack_frame(process, cur_fp) - print "" - if this_module is not None: - module_list.append(this_module) - frame_num = frame_num + 1 - next_pc = 0 - next_fp = 0 - if target.triple[ - 0:6] == "x86_64" or target.triple[ - 0:4] == "i386" or target.triple[ - 0:3] == "arm": - error = lldb.SBError() - next_pc = process.ReadPointerFromMemory( - cur_fp + process.GetAddressByteSize(), error) - if not error.Success(): - next_pc = 0 - next_fp = process.ReadPointerFromMemory(cur_fp, error) - if not error.Success(): - next_fp = 0 - # Clear the 0th bit for arm frames - this indicates it is a thumb frame - if target.triple[0:3] == "arm" and (next_pc & 1) == 1: - next_pc = next_pc & ~1 - cur_pc = next_pc - cur_fp = next_fp - this_module = backtrace_print_frame(target, frame_num, cur_pc, cur_fp) - print_stack_frame(process, cur_fp) - print "" - if this_module is not None: - module_list.append(this_module) - return [module_list, address_list] - - -def print_stack_frame(process, fp): - if fp == 0 or fp == lldb.LLDB_INVALID_ADDRESS or fp == 1: - return - addr_size = process.GetAddressByteSize() - addr = fp - (2 * addr_size) - i = 0 - outline = "Stack frame from $fp-%d: " % (2 * addr_size) - error = lldb.SBError() - try: - while i < 5 and error.Success(): - address = process.ReadPointerFromMemory( - addr + (i * addr_size), error) - outline += " 0x%x" % address - i += 1 - print outline - except Exception: - return - - -def diagnose_unwind(debugger, command, result, dict): - """ - Gather diagnostic information to help debug incorrect unwind (backtrace) - behavior in lldb. When there is a backtrace that doesn't look - correct, run this command with the correct thread selected and a - large amount of diagnostic information will be printed, it is likely - to be helpful when reporting the problem. - """ - - command_args = shlex.split(command) - parser = create_diagnose_unwind_options() - try: - (options, args) = parser.parse_args(command_args) - except: - return - target = debugger.GetSelectedTarget() - if target: - process = target.GetProcess() - if process: - thread = process.GetSelectedThread() - if thread: - lldb_versions_match = re.search( - r'[lL][lL][dD][bB]-(\d+)([.](\d+))?([.](\d+))?', - debugger.GetVersionString()) - lldb_version = 0 - lldb_minor = 0 - if len(lldb_versions_match.groups() - ) >= 1 and lldb_versions_match.groups()[0]: - lldb_major = int(lldb_versions_match.groups()[0]) - if len(lldb_versions_match.groups() - ) >= 5 and lldb_versions_match.groups()[4]: - lldb_minor = int(lldb_versions_match.groups()[4]) - - modules_seen = [] - addresses_seen = [] - - print 'LLDB version %s' % debugger.GetVersionString() - print 'Unwind diagnostics for thread %d' % thread.GetIndexID() - print "" - print "=============================================================================================" - print "" - print "OS plugin setting:" - debugger.HandleCommand( - "settings show target.process.python-os-plugin-path") - print "" - print "Live register context:" - thread.SetSelectedFrame(0) - debugger.HandleCommand("register read") - print "" - print "=============================================================================================" - print "" - print "lldb's unwind algorithm:" - print "" - frame_num = 0 - for frame in thread.frames: - if not frame.IsInlined(): - this_module = backtrace_print_frame( - target, frame_num, frame.GetPC(), frame.GetFP()) - print_stack_frame(process, frame.GetFP()) - print "" - if this_module is not None: - modules_seen.append(this_module) - addresses_seen.append(frame.GetPC()) - frame_num = frame_num + 1 - print "" - print "=============================================================================================" - print "" - print "Simple stack walk algorithm:" - print "" - (module_list, address_list) = simple_backtrace(debugger) - if module_list and module_list is not None: - modules_seen += module_list - if address_list and address_list is not None: - addresses_seen = set(addresses_seen) - addresses_seen.update(set(address_list)) - - print "" - print "=============================================================================================" - print "" - print "Modules seen in stack walks:" - print "" - modules_already_seen = set() - for module in modules_seen: - if module is not None and module.GetFileSpec().GetFilename() is not None: - if not module.GetFileSpec().GetFilename() in modules_already_seen: - debugger.HandleCommand( - 'image list %s' % - module.GetFileSpec().GetFilename()) - modules_already_seen.add( - module.GetFileSpec().GetFilename()) - - print "" - print "=============================================================================================" - print "" - print "Disassembly ofaddresses seen in stack walks:" - print "" - additional_addresses_to_disassemble = addresses_seen - for frame in thread.frames: - if not frame.IsInlined(): - print "--------------------------------------------------------------------------------------" - print "" - print "Disassembly of %s, frame %d, address 0x%x" % (frame.GetFunctionName(), frame.GetFrameID(), frame.GetPC()) - print "" - if target.triple[ - 0:6] == "x86_64" or target.triple[ - 0:4] == "i386": - debugger.HandleCommand( - 'disassemble -F att -a 0x%x' % frame.GetPC()) - else: - debugger.HandleCommand( - 'disassemble -a 0x%x' % - frame.GetPC()) - if frame.GetPC() in additional_addresses_to_disassemble: - additional_addresses_to_disassemble.remove( - frame.GetPC()) - - for address in list(additional_addresses_to_disassemble): - print "--------------------------------------------------------------------------------------" - print "" - print "Disassembly of 0x%x" % address - print "" - if target.triple[ - 0:6] == "x86_64" or target.triple[ - 0:4] == "i386": - debugger.HandleCommand( - 'disassemble -F att -a 0x%x' % address) - else: - debugger.HandleCommand('disassemble -a 0x%x' % address) - - print "" - print "=============================================================================================" - print "" - additional_addresses_to_show_unwind = addresses_seen - for frame in thread.frames: - if not frame.IsInlined(): - print "--------------------------------------------------------------------------------------" - print "" - print "Unwind instructions for %s, frame %d" % (frame.GetFunctionName(), frame.GetFrameID()) - print "" - debugger.HandleCommand( - 'image show-unwind -a "0x%x"' % frame.GetPC()) - if frame.GetPC() in additional_addresses_to_show_unwind: - additional_addresses_to_show_unwind.remove( - frame.GetPC()) - - for address in list(additional_addresses_to_show_unwind): - print "--------------------------------------------------------------------------------------" - print "" - print "Unwind instructions for 0x%x" % address - print "" - debugger.HandleCommand( - 'image show-unwind -a "0x%x"' % address) - - -def create_diagnose_unwind_options(): - usage = "usage: %prog" - description = '''Print diagnostic information about a thread backtrace which will help to debug unwind problems''' - parser = optparse.OptionParser( - description=description, - prog='diagnose_unwind', - usage=usage) - return parser - -lldb.debugger.HandleCommand( - 'command script add -f %s.diagnose_unwind diagnose-unwind' % - __name__) -print 'The "diagnose-unwind" command has been installed, type "help diagnose-unwind" for detailed help.' |