blob: 99c571f973c82b501602d0677d5fd73e069dab86 [file] [log] [blame]
# Copyright (C) 2021 Free Software Foundation, Inc.
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 3 of the License, or
# (at your option) any later version.
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# GNU General Public License for more details.
# You should have received a copy of the GNU General Public License
# along with this program. If not, see <>.
import gdb
from gdb.unwinder import Unwinder
# Set this to the stack level the backtrace should be corrupted at.
# This will only work for frame 1, 3, or 5 in the test this unwinder
# was written for.
stop_at_level = None
# Set this to the stack frame size of frames 1, 3, and 5. These
# frames will all have the same stack frame size as they are the same
# function called recursively.
stack_adjust = None
class FrameId(object):
def __init__(self, sp, pc):
self._sp = sp
self._pc = pc
def sp(self):
return self._sp
def pc(self):
return self._pc
class TestUnwinder(Unwinder):
def __init__(self):
Unwinder.__init__(self, "stop at level")
def __call__(self, pending_frame):
global stop_at_level
global stack_adjust
if stop_at_level is None or pending_frame.level() != stop_at_level:
return None
if stack_adjust is None:
raise gdb.GdbError("invalid stack_adjust")
if not stop_at_level in [1, 3, 5]:
raise gdb.GdbError("invalid stop_at_level")
sp_desc = pending_frame.architecture().registers().find("sp")
sp = pending_frame.read_register(sp_desc) + stack_adjust
pc = (gdb.lookup_symbol("normal_func"))[0].value().address
unwinder = pending_frame.create_unwind_info(FrameId(sp, pc))
for reg in pending_frame.architecture().registers("general"):
val = pending_frame.read_register(reg)
unwinder.add_saved_register(reg, val)
return unwinder
gdb.unwinder.register_unwinder(None, TestUnwinder(), True)
# When loaded, it is expected that the stack looks like:
# main -> normal_func -> inline_func -> normal_func -> inline_func -> normal_func -> inline_func
# Compute the stack frame size of normal_func, which has inline_func
# inlined within it.
f0 = gdb.newest_frame()
f1 = f0.older()
f2 = f1.older()
f0_sp = f0.read_register("sp")
f2_sp = f2.read_register("sp")
stack_adjust = f2_sp - f0_sp